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Sample records for repress anthocyanin synthesis

  1. Anthocyanin synthesis in native and wound periderms of potato.

    PubMed

    Fogelman, Edna; Tanami, Sivan; Ginzberg, Idit

    2015-04-01

    Skin color of red potatoes is due to accumulation of anthocyanins in the tuber periderm, a protective tissue that replaces the epidermis at an early stage of tuber development. The periderm consists of external layers of suberized phellem cells making up the skin, and internal layers of parenchyma-like phelloderm cells. Red pigmentation is an important marketing factor for red-skinned potatoes. However, injuries to the tuber surface, which are common in the potato industry, result in the development of a wound periderm that is devoid of the characteristic red coloration. To study the reason for these differences in anthocyanin accumulation, the expression level of anthocyanin biosynthesis genes and regulators was monitored in native and wound periderm using microarray analysis and quantitative polymerase chain reaction. We found significantly higher expression of the anthocyanin pathway in the phelloderm cells compared with the skin and tuber-flesh samples. However, in wound periderm, the anthocyanin pathway was strongly downregulated relative to the native periderm. This was true for two developmental stages of the native periderm--'immature', when the skin is prone to skinning injuries, and 'mature', following skin set--suggesting that anthocyanin synthesis continues postharvest. Wound-induced expression of steroidal glycoalkaloid glycosyltransferases, suberin-related 3-ketoacyl-CoA synthase and actin indicated that downregulation of the anthocyanin-specific pathway does not reflect global repression of the wound-periderm transcriptome. Loss of pigmentation may result from reduced expression of the Myb-bHLH-WD40 anthocyanin regulatory complex--a possible candidate might be the bHLH transcription factor JAF13. PMID:25156080

  2. Anthocyanin synthesis in native and wound periderms of potato.

    PubMed

    Fogelman, Edna; Tanami, Sivan; Ginzberg, Idit

    2015-04-01

    Skin color of red potatoes is due to accumulation of anthocyanins in the tuber periderm, a protective tissue that replaces the epidermis at an early stage of tuber development. The periderm consists of external layers of suberized phellem cells making up the skin, and internal layers of parenchyma-like phelloderm cells. Red pigmentation is an important marketing factor for red-skinned potatoes. However, injuries to the tuber surface, which are common in the potato industry, result in the development of a wound periderm that is devoid of the characteristic red coloration. To study the reason for these differences in anthocyanin accumulation, the expression level of anthocyanin biosynthesis genes and regulators was monitored in native and wound periderm using microarray analysis and quantitative polymerase chain reaction. We found significantly higher expression of the anthocyanin pathway in the phelloderm cells compared with the skin and tuber-flesh samples. However, in wound periderm, the anthocyanin pathway was strongly downregulated relative to the native periderm. This was true for two developmental stages of the native periderm--'immature', when the skin is prone to skinning injuries, and 'mature', following skin set--suggesting that anthocyanin synthesis continues postharvest. Wound-induced expression of steroidal glycoalkaloid glycosyltransferases, suberin-related 3-ketoacyl-CoA synthase and actin indicated that downregulation of the anthocyanin-specific pathway does not reflect global repression of the wound-periderm transcriptome. Loss of pigmentation may result from reduced expression of the Myb-bHLH-WD40 anthocyanin regulatory complex--a possible candidate might be the bHLH transcription factor JAF13.

  3. Photocontrol of Anthocyanin Synthesis: III. The Action of Streptomycin on the Synthesis of Chlorophyll and Anthocyanin.

    PubMed

    Mancinelli, A L; Yang, C P; Lindquist, P; Anderson, O R; Rabino, I

    1975-02-01

    Streptomycin enhances the synthesis of anthocyanins and inhibits the synthesis of chlorophylls and the development of chloroplasts in dark-grown seedlings of cabbage (Brassica oleracea), mustard (Sinapis alba), tomato (Lycopersicon esculentum), and turnip (Brassica rapa) exposed to prolonged periods of irradiation in various spectral regions. These results suggest that the contribution of photosynthesis to light-dependent high irradiance reaction anthocyanin synthesis in seedlings of cabbage, mustard, tomato, and turnip is minimal, if any at all. So far, phytochrome is the only photoreceptor whose action in the control of light-dependent anthocyanin synthesis in seedlings of cabbage, mustard, tomato, and turnip has been satisfactorily demonstrated.

  4. Photocontrol of Anthocyanin Synthesis: III. The Action of Streptomycin on the Synthesis of Chlorophyll and Anthocyanin.

    PubMed

    Mancinelli, A L; Yang, C P; Lindquist, P; Anderson, O R; Rabino, I

    1975-02-01

    Streptomycin enhances the synthesis of anthocyanins and inhibits the synthesis of chlorophylls and the development of chloroplasts in dark-grown seedlings of cabbage (Brassica oleracea), mustard (Sinapis alba), tomato (Lycopersicon esculentum), and turnip (Brassica rapa) exposed to prolonged periods of irradiation in various spectral regions. These results suggest that the contribution of photosynthesis to light-dependent high irradiance reaction anthocyanin synthesis in seedlings of cabbage, mustard, tomato, and turnip is minimal, if any at all. So far, phytochrome is the only photoreceptor whose action in the control of light-dependent anthocyanin synthesis in seedlings of cabbage, mustard, tomato, and turnip has been satisfactorily demonstrated. PMID:16659061

  5. REPRESSION OF TRYPTOPHANASE SYNTHESIS IN ESCHERICHIA COLI.

    PubMed

    BEGGS, W H; LICHSTEIN, H C

    1965-04-01

    Beggs, William H. (University of Cincinnati, Cincinnati, Ohio), and Herman C. Lichstein. Repression of tryptophanase synthesis in Escherichia coli. J. Bacteriol. 89:996-1004. 1965.-The nature of the glucose effect on tryptophanase in Escherichia coli (Crookes) was investigated to test the catabolite-repression hypothesis. Under static conditions of growth in the presence of 0.005 m glucose, tryptophanase was repressed and remained so upon continued static incubation subsequent to glucose exhaustion. Aeration following glucose exhaustion under static cultural conditions resulted in rapid enzyme synthesis. In the absence of glucose, certain amino acids repressed tryptophanase synthesis early in the growth cycle under aerated conditions. An inverse relationship was observed between the concentration of acid-hydrolyzed casein and the level of tryptophanase. At 3 hr, enzyme activity in cells grown in media containing 0.05% acid-hydrolyzed casein was at least five times that of cells grown in the presence of 1% casein. Addition of 0.005 m d- or l-serine to a 0.05% acid-hydrolyzed casein medium rendered the medium capable of strongly repressing tryptophanase. Glucose-expended medium was prepared by allowing cells to grow and exhaust glucose in static culture. When this expended medium was recovered and inoculated with fresh cells not previously exposed to glucose, tryptophanase synthesis was repressed for a short period in shake culture, but in static culture enzyme synthesis was only slightly affected. When the expended medium was prepared from shake cultures, fresh cells were not repressed strongly when subsequent incubation was carried out aerobically. The tryptophan pool in glucose-repressed cells grown in shake culture was appreciably less than in cells grown in the absence of glucose or in cells undergoing synthesis of tryptophanase after exhaustion of the sugar.

  6. The Arabidopsis Transcription Factor ANAC032 Represses Anthocyanin Biosynthesis in Response to High Sucrose and Oxidative and Abiotic Stresses

    PubMed Central

    Mahmood, Kashif; Xu, Zhenhua; El-Kereamy, Ashraf; Casaretto, José A.; Rothstein, Steven J.

    2016-01-01

    Production of anthocyanins is one of the adaptive responses employed by plants during stress conditions. During stress, anthocyanin biosynthesis is mainly regulated at the transcriptional level via a complex interplay between activators and repressors of anthocyanin biosynthesis genes. In this study, we investigated the role of a NAC transcription factor, ANAC032, in the regulation of anthocyanin biosynthesis during stress conditions. ANAC032 expression was found to be induced by exogenous sucrose as well as high light (HL) stress. Using biochemical, molecular and transgenic approaches, we show that ANAC032 represses anthocyanin biosynthesis in response to sucrose treatment, HL and oxidative stress. ANAC032 was found to negatively affect anthocyanin accumulation and the expression of anthocyanin biosynthesis (DFR, ANS/LDOX) and positive regulatory (TT8) genes as demonstrated in overexpression line (35S:ANAC032) compared to wild-type under HL stress. The chimeric repressor line (35S:ANAC032-SRDX) exhibited the opposite expression patterns for these genes. The negative impact of ANAC032 on the expression of DFR, ANS/LDOX and TT8 was found to be correlated with the altered expression of negative regulators of anthocyanin biosynthesis, AtMYBL2 and SPL9. In addition to this, ANAC032 also repressed the MeJA- and ABA-induced anthocyanin biosynthesis. As a result, transgenic lines overexpressing ANAC032 (35S:ANAC032) produced drastically reduced levels of anthocyanin pigment compared to wild-type when challenged with salinity stress. However, transgenic chimeric repressor lines (35S:ANAC032-SRDX) exhibited the opposite phenotype. Our results suggest that ANAC032 functions as a negative regulator of anthocyanin biosynthesis in Arabidopsis thaliana during stress conditions. PMID:27790239

  7. COP1/SPA ubiquitin ligase complexes repress anthocyanin accumulation under low light and high light conditions.

    PubMed

    Maier, Alexander; Hoecker, Ute

    2015-01-01

    In Arabidopsis and many other plant species, anthocyanin pigments accumulate only after light exposure and not in darkness. Excess light of very high fluence rates leads to a further, very strong increase in anthocyanin levels. How excess light is sensed is not well understood. Here, we show that mutations in the key repressor of light signaling, the COP1/SPA complex, cause a strong hyperaccumulation of anthocyanins not only under normal light but also under excess, high light conditions. Hence, normal light signaling via COP1/SPA is required to prevent hyperaccumulation of anthocyanins under these high light conditions. However, since cop1 and spa mutants show a similar high-light responsiveness of anthocyanin accumulation as the wild type it remains to be resolved whether COP1/SPA is directly involved in the high-light response itself.

  8. Mechanism of catabolite repression of tryptophanase synthesis in Escherichia coli.

    PubMed

    Isaacs, H; Chao, D; Yanofsky, C; Saier, M H

    1994-08-01

    Repression of tryptophanase (tryptophan indole-lyase) by glucose and its non-metabolizable analogue methyl alpha-glucoside has been studied employing a series of isogenic strains of Escherichia coli lacking cyclic AMP phosphodiesterase and altered for two of the proteins of the phosphoenolpyruvate:sugar phosphotransferase system (PTS), Enzyme I and Enzyme IIAGlc. Basal activity of tryptophanase was depressed mildly by inclusion of glucose in the growth medium, but inducible tryptophanase synthesis was subject to strong glucose repression in the parental strain, which exhibited normal PTS enzyme activities. Methyl alpha-glucoside was without effect in this strain. Loss of Enzyme I decreased sensitivity to repression by glucose but enhanced sensitivity to repression by methyl alpha-glucoside. Loss of Enzyme IIAGlc activity largely abolished repression by methyl alpha-glucoside but had a less severe effect on glucose repression. The repressive effects of both sugars were fully reversed by inclusion of cyclic AMP in the growth medium. Tryptophan uptake under the same conditions was inhibited weakly by glucose and more strongly by methyl alpha-glucoside in the parental strain. Inhibition by both sugars was alleviated by partial loss of Enzyme I. Inhibition by methyl alpha-glucoside appeared to be largely due to energy competition and was not responsible for repression of tryptophanase synthesis. Measurement of net production of cyclic AMP as well as intracellular concentrations of cyclic AMP revealed a good correlation with intensity of repression. The results suggest that while basal tryptophanase synthesis is relatively insensitive to catabolite repression, inducible synthesis is subject to strong repression by two distinct mechanisms, one dependent on enzyme IIAGlc of the PTS and the other independent of this protein. Both mechanisms are attributable to depressed rates of cyclic AMP synthesis. No evidence for a cyclic-AMP-independent mechanism of catabolite

  9. [Induction and repression of the collagenase synthesis in Acinetobacter sp].

    PubMed

    Monboisse, J C; Labadie, J; Gouet, P

    1979-05-01

    The synthesis of collagenase in Acinetobacter sp. was found to be inducible by denatured collagen and by its high molecular weight fragments. The presence in the inducer of part of the tertiary structure appear to be indispensable. On the other hand, an addition of Casamino acids, meat protein hydrolysate, or a mixture of amino acids with a similar composition to gelatin does not stimulate collagenase synthesis. Enzyme production was severely repressed in the early phase of growth by glucose, arabinose, and ribose, single amino acids, proline, hydroxyproline, alanine, glutamic acid or casein acid hydrolysate. A mechanism of repression similar to catabolite repression was involved in the phenomenon caused by carbohydrates. However, the fact that cyclic adenosine 3'5-monophosphate did not overcome the repression caused by amino acids or Casamino acids, in contrast to classical catabolite repression, suggests that these two forms of repression may be distinct.

  10. Adaptation of Arabidopsis to nitrogen limitation involves induction of anthocyanin synthesis which is controlled by the NLA gene.

    PubMed

    Peng, Mingsheng; Hudson, Darryl; Schofield, Andrew; Tsao, Rong; Yang, Raymond; Gu, Honglan; Bi, Yong-Mei; Rothstein, Steven J

    2008-01-01

    Plants can survive a limiting nitrogen (N) supply by developing a set of N limitation adaptive responses. However, the Arabidopsis nla (nitrogen limitation adaptation) mutant fails to produce such responses, and cannot adapt to N limitation. In this study, the nla mutant was utilized to understand further the effect of NLA on Arabidopsis adaptation to N limitation. Grown with limiting N, the nla mutant could not accumulate anthocyanins and instead produced an N limitation-induced early senescence phenotype. In contrast, when supplied with limiting N and limiting phosphorus (Pi), the nla mutants accumulated abundant anthocyanins and did not show the N limitation-induced early senescence phenotype. These results support the hypothesis that Arabidopsis has a specific pathway to control N limitation-induced anthocyanin synthesis, and the nla mutation disrupts this pathway. However, the nla mutation does not affect the Pi limitation-induced anthocyanin synthesis pathway. Therefore, Pi limitation induced the nla mutant to accumulate anthocyanins under N limitation and allowed this mutant to adapt to N limitation. Under N limitation, the nla mutant had a significantly down-regulated expression of many genes functioning in anthocyanin synthesis, and an enhanced expression of genes involved in lignin production. Correspondingly, the nla mutant grown with limiting N showed a significantly lower production of anthocyanins (particularly cyanidins) and an increase in lignin contents compared with wild-type plants. These data suggest that NLA controls Arabidopsis adaptability to N limitation by channelling the phenylpropanoid metabolic flux to the induced anthocyanin synthesis, which is important for Arabidopsis to adapt to N limitation. PMID:18552353

  11. The MYB182 Protein Down-Regulates Proanthocyanidin and Anthocyanin Biosynthesis in Poplar by Repressing Both Structural and Regulatory Flavonoid Genes1[OPEN

    PubMed Central

    Yoshida, Kazuko; Ma, Dawei; Constabel, C. Peter

    2015-01-01

    Trees in the genus Populus (poplar) contain phenolic secondary metabolites including the proanthocyanidins (PAs), which help to adapt these widespread trees to diverse environments. The transcriptional activation of PA biosynthesis in response to herbivory and ultraviolet light stress has been documented in poplar leaves, and a regulator of this process, the R2R3-MYB transcription factor MYB134, has been identified. MYB134-overexpressing transgenic plants show a strong high-PA phenotype. Analysis of these transgenic plants suggested the involvement of additional MYB transcription factors, including repressor-like MYB factors. Here, MYB182, a subgroup 4 MYB factor, was found to act as a negative regulator of the flavonoid pathway. Overexpression of MYB182 in hairy root culture and whole poplar plants led to reduced PA and anthocyanin levels as well as a reduction in the expression of key flavonoid genes. Similarly, a reduced accumulation of transcripts of a MYB PA activator and a basic helix-loop-helix cofactor was observed in MYB182-overexpressing hairy roots. Transient promoter activation assays in poplar cell culture demonstrated that MYB182 can disrupt transcriptional activation by MYB134 and that the basic helix-loop-helix-binding motif of MYB182 was essential for repression. Microarray analysis of transgenic plants demonstrated that down-regulated targets of MYB182 also include shikimate pathway genes. This work shows that MYB182 plays an important role in the fine-tuning of MYB134-mediated flavonoid metabolism. PMID:25624398

  12. Photocontrol of anthocyanin synthesis in turnip seedlings : IV. The effect of feeding precursors.

    PubMed

    Grill, R

    1967-03-01

    Separation of hypocotyls and cotyledons of turnip seedlings (Brassica rapa) reduced the yield of anthocyanin from the former. Feeding with a combination of phenylalanine, acetate and glucose (PAG) considerably increased anthocyanin synthesis in these excised hypocotyls. In blue light the yield equalled that of the controls with cotyledons attached but, in far-red, the maximum obtained was never more than 55% of the controls.A long pre-treatment with red light markedly reduced anthocyanin formation in far-red. In young seedlings (presumed to be still capable of de novo phytochrome synthesis) this effect could largely be overcome by feeding with the same phenylalanine-acetate-glucose medium used with isolated hypocotyls but, in older seedlings, feeding did not prevent the effect of pre-irradiation with red light. It is concluded that red light not only destroys phytochrome but also leads to substrate disappearance.Without feeding pre-irradiation with red did not materially affect the yield from blue light; the addition of the phenylalanine-acetate-glucose mixture caused a significant increase compared with treatments without pre-red in both older and younger seedlings, particularly in the hypocotyl. The blue sensitive system thus appears to be independent of phytochrome destruction.Feeding also increased yields in red light. In water 72 hours red was no more effective than 24 hours: with PAG the longer irradiation period resulted in a considerably increased yield, especially in younger seedlings. The low yields in red light thus appear to result partly from substrate deficiency.

  13. Photocontrol of anthocyanin synthesis in turnip seedlings : IV. The effect of feeding precursors.

    PubMed

    Grill, R

    1967-03-01

    Separation of hypocotyls and cotyledons of turnip seedlings (Brassica rapa) reduced the yield of anthocyanin from the former. Feeding with a combination of phenylalanine, acetate and glucose (PAG) considerably increased anthocyanin synthesis in these excised hypocotyls. In blue light the yield equalled that of the controls with cotyledons attached but, in far-red, the maximum obtained was never more than 55% of the controls.A long pre-treatment with red light markedly reduced anthocyanin formation in far-red. In young seedlings (presumed to be still capable of de novo phytochrome synthesis) this effect could largely be overcome by feeding with the same phenylalanine-acetate-glucose medium used with isolated hypocotyls but, in older seedlings, feeding did not prevent the effect of pre-irradiation with red light. It is concluded that red light not only destroys phytochrome but also leads to substrate disappearance.Without feeding pre-irradiation with red did not materially affect the yield from blue light; the addition of the phenylalanine-acetate-glucose mixture caused a significant increase compared with treatments without pre-red in both older and younger seedlings, particularly in the hypocotyl. The blue sensitive system thus appears to be independent of phytochrome destruction.Feeding also increased yields in red light. In water 72 hours red was no more effective than 24 hours: with PAG the longer irradiation period resulted in a considerably increased yield, especially in younger seedlings. The low yields in red light thus appear to result partly from substrate deficiency. PMID:24549375

  14. Repression of Escherichia coli carbamoylphosphate synthase: relationships with enzyme synthesis in the arginine and pyrimidine pathways.

    PubMed Central

    Piérard, A; Glansdorff, N; Gigot, D; Crabeel, M; Halleux, P; Thiry, L

    1976-01-01

    Cumulative repression of Escherichia coli carbamoylphosphate synthase (CPSase; EC 2.7.2.9) by arginine and pyrimidine was analyzed in relation to control enzyme synthesis in the arginine and pyrimidine pathways. The expression of carA and carB, the adjacent genes that specify the two subunits of the enzyme, was estimated by means of an in vitro complementation assay. The synthesis of each gene product was found to be under repression control. Coordinate expression of the two genes was observed under most conditions investigated. They might thus form an operon. The preparation of strains blocked in the degradation of cytidine and harboring leaky mutations affecting several steps of pyrimidine nucleotide synthesis made it possible to distinguish between the effects of cytidine and uridine compounds in the repression of the pyrimidine pathway enzymes. The data obtained suggest that derivatives of both cytidine and uridine participate in the repression of CPSase. In addition, repression of CPSase by arginine did not appear to occur unless pyrimidines were present at a significant intracellular concentration. This observation, together with our previous report that argR mutations impair the cumulative repression of CPSase, suggests that this control is mediated through the concerted effects of regulatory elements specific for the arginine and pyrimidine pathways. PMID:179975

  15. Possible involvement of a tetrahydrobiopterin in photoreception for UV-B-induced anthocyanin synthesis in carrot.

    PubMed

    Takeda, Junko; Nakata, Rieko; Ueno, Hiroshi; Murakami, Akio; Iseki, Mineo; Watanabe, Masakatsu

    2014-01-01

    Our previous studies of action spectra for UV-B-induced anthocyanin accumulation in cultured carrot cells indicated that a reduced form of pterin, possibly tetrahydrobiopterin, contributes to UV-B photoreception. In this report, we provide additional evidence for the involvement of pterin in UV-B light sensing. UV-B-induced phenylalanine ammonia-lyase (PAL) activity was considerably suppressed by N-acetylserotonin (an inhibitor of tetrahydrobiopterin biosynthesis), and this suppression was partially recovered by adding biopterin or tetrahydrobiobiopterin. In addition, protein(s) specifically bound to biopterin were detected by radiolabeling experiments in N-acetylserotonin-treated cells. Furthermore, diphenyleneiodonium, a potent inhibitor of electron transfer, completely suppressed UV-B-induced PAL activity. These results suggest the occurrence of an unidentified UV-B photoreceptor (other than UVR8, the tryptophan-based UV-B sensor originally identified in Arabidopsis) with reduced pterin in carrot cells. After reexamining published action spectra, we suggest that anthocyanin synthesis is coordinately regulated by these two UV-B sensors.

  16. Transient repression of catabolite-sensitive enzyme synthesis elicited by 2,4-dinitrophenol.

    PubMed

    Oki, R

    1975-09-01

    Transient inhibition of catabolic enzyme synthesis in Escherichia coli occurred when a low concentration of 2,4-dinitrophenol (DNP) was simultaneously added with inducer. Using mutant strains defective for gamma-gene product or constitutive for lac enzymes, it was found that the inhibition is not due to the exclusion of inducer by uncoupling. The addition of cyclic adenosine 3',5'-monophosphate overcame repression. The components of the lac operon coordinately responded to DNP inhibition. From deoxyribonucleic acid-ribonucleic acid hybridization experiments, it was found that the inhibition of beta-galactosidase induction occurred at the level of messenger ribonucleic acid synthesis specific for the lac operon. It seems probable that DNP represses induction in a similar manner to that of transient repression observed upon the addition of glucose. Furthermore, it was found that transient repression disappeared if cells were preincubated with DNP before induction. This indicates that new contact of cells with DNP is obligatory for transient repression. From these results, it is suggested that the cell membrane may be responsible for regulation of catabolite-sensitive enzyme synthesis. PMID:169228

  17. Regulatory effect of stems on sucrose-induced chlorophyll degradation and anthocyanin synthesis in Egeria densa leaves.

    PubMed

    Momose, Tadayuki; Ozeki, Yoshihiro

    2013-11-01

    Detached green leaves of the aquatic plant Egeria densa showed chlorophyll degradation and turned red due to induced anthocyanin synthesis incubated in 0.1 M sucrose under continuous light for 7-10 days. If the leaves were placed in water, only chlorophyll degradation occurred and the detached leaves turned yellow. The levels of endogenous total carbohydrates increased in detached leaves cultured in the sucrose solution but only increased marginally in water. If the leaves were still attached to a piece of stem, with a node on either side of the single leaf whorl, then they did not accumulate anthocyanin in culture with 0.1 M sucrose. These leaves showed a similar increase in total carbohydrates and degradation of chlorophyll as detached leaves. Attached leaves, in which the midrib had been cut in situ, showed localized accumulation of anthocyanin in the leaf tissue distal to the cut in the midrib when cultured in 0.1 M sucrose. These results suggest that the stem plays a regulatory role in anthocyanin synthesis in attached leaves cultured in a sucrose solution but does not influence chlorophyll degradation or carbohydrate accumulation. PMID:23864418

  18. Thermolabile repression of cephalosporinase synthesis in Citrobacter freundii.

    PubMed

    Sawai, T; Nakajima, S; Morohoshi, T; Yamagishi, S

    1977-11-01

    An unusual regulatory system of cephalosporinase synthesis in Citrobacter freundii has been found. When the bacteria are grown at 20 C, the cephalosporinase is synthesized as a typical inducible enzyme and benzylpenicillin acts as an effective inducer. The enzyme, however, is synthesized in the absence of the inducer at growth temperatures above 25 C. when the growth temperature is shifted from 20 C to 37 C, the induction of enzyme synthesis is observed after about one half of the organism doubling time, but it does not occur in the presence of chloramphenicol. The reverse control mutants, the enzyme constitutive synthesis of which is markedly depressed by benzylpenicillin, were isolated from the C. freundii wild strain. The possibility that the enzyme synthesis is governed by a regulatory system analogous to the its mutant of the lac operon in Escherichia coli was suggested. PMID:203825

  19. Repression of In Vivo Synthesis of the Mitochondrial Elongation Factors T and G in Saccharomyces fragilis

    PubMed Central

    Richter, D.

    1973-01-01

    In vivo synthesis of the mitochondrial elongation factors T and G in the yeast Saccharomyces fragilis can be repressed. Enzymatic activity assays and immunochemical titration methods reveal that cells grown in the presence of 8% glucose or in the absence of oxygen contain relatively lower amounts of mitochondrial elongation factors than cells grown in the presence of lactate. In contrast, in vivo production of the cytoplasmic elongation factors 1 and 2 does not respond to such a change of extracellular conditions. The rate of growth does not affect the level of the mitochondrial elongation factors. Production of both enzymes is almost constant during logarithmic growth, but decreases when the stationary phase is reached. Chloramphenicol, an inhibitor of mitochondrial protein synthesis, does not block but, rather, seems to enhance the in vivo synthesis of mitochondrial T or G. PMID:4717524

  20. Velvet-mediated repression of β-glucan synthesis in Aspergillus nidulans spores

    PubMed Central

    Park, Hee-Soo; Man Yu, Yeong; Lee, Mi-Kyung; Jae Maeng, Pil; Chang Kim, Sun; Yu, Jae-Hyuk

    2015-01-01

    Beta-glucans are a heterologous group of fibrous glucose polymers that are a major constituent of cell walls in Ascomycetes and Basidiomycetes fungi. Synthesis of β (1,3)- and (1,6)-glucans is coordinated with fungal cell growth and development, thus, is under tight genetic regulation. Here, we report that β-glucan synthesis in both asexual and sexual spores is turned off by the NF-kB like fungal regulators VosA and VelB in Aspergillus nidulans. Our genetic and genomic analyses have revealed that both VosA and VelB are necessary for proper down-regulation of cell wall biosynthetic genes including those associated with β-glucan synthesis in both types of spores. The deletion of vosA or velB results in elevated accumulation of β-glucan in asexual spores. Double mutant analyses indicate that VosA and VelB play an inter-dependent role in repressing β-glucan synthesis in asexual spores. In vivo chromatin immuno-precipitation analysis shows that both VelB and VosA bind to the promoter region of the β-glucan synthase gene fksA in asexual spores. Similarly, VosA is required for proper repression of β-glucan synthesis in sexual spores. In summary, the VosA-VelB hetero-complex is a key regulatory unit tightly controlling proper levels of β-glucan synthesis in asexual and sexual spores. PMID:25960370

  1. The Unphosphorylated EIIANtr Protein Represses the Synthesis of Alkylresorcinols in Azotobacter vinelandii

    PubMed Central

    Muriel-Millán, Luis Felipe; Moreno, Soledad; Romero, Yanet; Bedoya-Pérez, Leidy Patricia; Castañeda, Miguel; Segura, Daniel; Espín, Guadalupe

    2015-01-01

    Upon encystment induction, Azotobacter vinelandii produces the phenolic lipids alkylresorcinols (ARs) that are structural components of the cysts. The enzymes responsible for the ARs synthesis are encoded in the arsABCD operon, whose expression is activated by ArpR. The transcription of arpR is initiated from an RpoS dependent promoter. The nitrogen-related phosphotransferase system (PTSNtr) is a global regulatory system present in Gram negative bacteria. It comprises the EINtr, NPr and EIIANtr proteins encoded by ptsP, ptsO and ptsN genes respectively. These proteins participate in a phosphoryl-group transfer from phosphoenolpyruvate to protein EIIANtr via the phosphotransferases EINtr and NPr. In A. vinelandii, the non-phosphorylated form of EIIANtr was previously shown to repress the synthesis of poly-ß-hydroxybutyrate. In this work, we show that PTSNtr also regulates the synthesis of ARs. In a strain that carries unphosphorylated EIIANtr, the expression of arpR was reduced, while synthesis of ARs and transcription of arsA were almost abrogated. The expression of arpR from an RpoS-independent promoter in this strain restored the ARs synthesis. Taken together these results indicate that unphosphorylated EIIANtr negatively affects activation of arpR transcription by RpoS. PMID:25642700

  2. A Conserved Network of Transcriptional Activators and Repressors Regulates Anthocyanin Pigmentation in Eudicots[C][W][OPEN

    PubMed Central

    Albert, Nick W.; Davies, Kevin M.; Lewis, David H.; Zhang, Huaibi; Montefiori, Mirco; Brendolise, Cyril; Boase, Murray R.; Ngo, Hanh; Jameson, Paula E.; Schwinn, Kathy E.

    2014-01-01

    Plants require sophisticated regulatory mechanisms to ensure the degree of anthocyanin pigmentation is appropriate to myriad developmental and environmental signals. Central to this process are the activity of MYB-bHLH-WD repeat (MBW) complexes that regulate the transcription of anthocyanin genes. In this study, the gene regulatory network that regulates anthocyanin synthesis in petunia (Petunia hybrida) has been characterized. Genetic and molecular evidence show that the R2R3-MYB, MYB27, is an anthocyanin repressor that functions as part of the MBW complex and represses transcription through its C-terminal EAR motif. MYB27 targets both the anthocyanin pathway genes and basic-helix-loop-helix (bHLH) ANTHOCYANIN1 (AN1), itself an essential component of the MBW activation complex for pigmentation. Other features of the regulatory network identified include inhibition of AN1 activity by the competitive R3-MYB repressor MYBx and the activation of AN1, MYB27, and MYBx by the MBW activation complex, providing for both reinforcement and feedback regulation. We also demonstrate the intercellular movement of the WDR protein (AN11) and R3-repressor (MYBx), which may facilitate anthocyanin pigment pattern formation. The fundamental features of this regulatory network in the Asterid model of petunia are similar to those in the Rosid model of Arabidopsis thaliana and are thus likely to be widespread in the Eudicots. PMID:24642943

  3. STAT3 Represses Nitric Oxide Synthesis in Human Macrophages upon Mycobacterium tuberculosis Infection

    PubMed Central

    Queval, Christophe J.; Song, Ok-Ryul; Deboosère, Nathalie; Delorme, Vincent; Debrie, Anne-Sophie; Iantomasi, Raffaella; Veyron-Churlet, Romain; Jouny, Samuel; Redhage, Keely; Deloison, Gaspard; Baulard, Alain; Chamaillard, Mathias; Locht, Camille; Brodin, Priscille

    2016-01-01

    Mycobacterium tuberculosis is a successful intracellular pathogen. Numerous host innate immune responses signaling pathways are induced upon mycobacterium invasion, however their impact on M. tuberculosis replication is not fully understood. Here we reinvestigate the role of STAT3 specifically inside human macrophages shortly after M. tuberculosis uptake. We first show that STAT3 activation is mediated by IL-10 and occurs in M. tuberculosis infected cells as well as in bystander non-colonized cells. STAT3 activation results in the inhibition of IL-6, TNF-α, IFN-γ and MIP-1β. We further demonstrate that STAT3 represses iNOS expression and NO synthesis. Accordingly, the inhibition of STAT3 is detrimental for M. tuberculosis intracellular replication. Our study thus points out STAT3 as a key host factor for M. tuberculosis intracellular establishment in the early stages of macrophage infection. PMID:27384401

  4. Anthocyanins as Functional Food Colors

    NASA Astrophysics Data System (ADS)

    Motohashi, Noboru; Sakagami, Hiroshi

    Anthocyanins, a proanthocyanidin-type of flavonoid, contain an abundance of functional phytochemicals and occur in fruits such as cranberry, blueberry, orange, apple and in vegetables such as tomato, sweet pepper, spinach, and radishes. Functional and essential diets have been ingested in daily life since the primitive era of history. When anthocyanins are coupled with some water-soluble sugar molecules, their color becomes red, yellow, violet, or blue. It is very intriguing that anthocyanins provide the colorful variety of pigments for pansies, petunias, plums, and other diverse flowers. Chlorophyll in various fruits and vegetables is the main green phyto-component, while anthocyanins are probably the most important visible plant pigments in the natural kingdom having specific colors. Anthocyanins have been clinically used in many folklore medicines worldwide. Anthocyanins could provide health benefits for age-related diseases as well as other diseases. Anthocyanins have higher antioxidant capacity against oxidative stress induced by excess reactive oxygen species (ROS) such as superoxide radicals, hydrogen peroxide, and thus the human body might be protected from oxidative injury by anthocyanins. On the basis of these facts, we review the synthesis of plant flavonoids and their ability to scavenge oxidants, inhibit or activate enzymes, and the safety of proanthocyanidins and anthocyanidins present in common foods.

  5. Positive selection of mutants defective in transcriptional repression of riboflavin synthesis by iron in the flavinogenic yeast Pichia guilliermondii.

    PubMed

    Boretsky, Yuriy R; Kapustyak, Kostyantyn Y; Fayura, Lyubov R; Stasyk, Oleh V; Stenchuk, Mykola M; Bobak, Yaroslav P; Drobot, Lyudmyla B; Sibirny, Andriy A

    2005-06-01

    It is known for many years that iron represses synthesis of riboflavin (RF) and most of RF-synthesizing enzymes in several yeast species, known as flavinogenic yeasts. However, the mechanism of such repression is not known. We have found that iron represses transcription of RIB1 and RIB7 genes coding for the first and the last enzymes of RF biosynthesis in the model flavinogenic organism Pichia guilliermondii. To decipher molecular mechanisms of iron-dependent repression, isolation and study of the regulatory mutants defective in corresponding regulation is desirable. However, no suitable methods for isolation of such mutants were previously available. We have produced a single-point transition mutation in the RIB1 gene. The corresponding rib1-86 mutant exhibits leaky phenotype and is unable to grow in iron-sufficient minimal medium without exogenous RF. However, it can grow in minimal iron-deficient medium without RF, or in iron-sufficient medium upon introduction of the previously-isolated regulatory mutation rib81, which leads to increase in RF production. Using the rib1-86 mutant as parental strain, a collection of mutants able to grow in iron-sufficient medium without exogenous RF has been isolated. The mutants appeared to be defective in regulation of RF biosynthesis and iron homeostasis and were divided into six new complementation groups. Study of one corresponding mutant, red6, showed derepression of RIB1 mRNA synthesis in iron-sufficient medium. PMID:15925311

  6. Arabidopsis CAPRICE (MYB) and GLABRA3 (bHLH) control tomato (Solanum lycopersicum) anthocyanin biosynthesis.

    PubMed

    Wada, Takuji; Kunihiro, Asuka; Tominaga-Wada, Rumi

    2014-01-01

    In Arabidopsis thaliana the MYB transcription factor CAPRICE (CPC) and the bHLH transcription factor GLABRA3 (GL3) are central regulators of root-hair differentiation and trichome initiation. By transforming the orthologous tomato genes SlTRY (CPC) and SlGL3 (GL3) into Arabidopsis, we demonstrated that these genes influence epidermal cell differentiation in Arabidopsis, suggesting that tomato and Arabidopsis partially use similar transcription factors for epidermal cell differentiation. CPC and GL3 are also known to be involved in anthocyanin biosynthesis. After transformation into tomato, 35S::CPC inhibited anthocyanin accumulation, whereas GL3::GL3 enhanced anthocyanin accumulation. Real-time reverse transcription PCR analyses showed that the expression of anthocyanin biosynthetic genes including Phe-ammonia lyase (PAL), the flavonoid pathway genes chalcone synthase (CHS), dihydroflavonol reductase (DFR), and anthocyanidin synthase (ANS) were repressed in 35S::CPC tomato. In contrast, the expression levels of PAL, CHS, DFR, and ANS were significantly higher in GL3::GL3 tomato compared with control plants. These results suggest that CPC and GL3 also influence anthocyanin pigment synthesis in tomato. PMID:25268379

  7. Arabidopsis CAPRICE (MYB) and GLABRA3 (bHLH) Control Tomato (Solanum lycopersicum) Anthocyanin Biosynthesis

    PubMed Central

    Wada, Takuji; Kunihiro, Asuka; Tominaga-Wada, Rumi

    2014-01-01

    In Arabidopsis thaliana the MYB transcription factor CAPRICE (CPC) and the bHLH transcription factor GLABRA3 (GL3) are central regulators of root-hair differentiation and trichome initiation. By transforming the orthologous tomato genes SlTRY (CPC) and SlGL3 (GL3) into Arabidopsis, we demonstrated that these genes influence epidermal cell differentiation in Arabidopsis, suggesting that tomato and Arabidopsis partially use similar transcription factors for epidermal cell differentiation. CPC and GL3 are also known to be involved in anthocyanin biosynthesis. After transformation into tomato, 35S::CPC inhibited anthocyanin accumulation, whereas GL3::GL3 enhanced anthocyanin accumulation. Real-time reverse transcription PCR analyses showed that the expression of anthocyanin biosynthetic genes including Phe-ammonia lyase (PAL), the flavonoid pathway genes chalcone synthase (CHS), dihydroflavonol reductase (DFR), and anthocyanidin synthase (ANS) were repressed in 35S::CPC tomato. In contrast, the expression levels of PAL, CHS, DFR, and ANS were significantly higher in GL3::GL3 tomato compared with control plants. These results suggest that CPC and GL3 also influence anthocyanin pigment synthesis in tomato. PMID:25268379

  8. Cooperative Action of Cdk1/cyclin B and SIRT1 Is Required for Mitotic Repression of rRNA Synthesis

    PubMed Central

    Voit, Renate; Seiler, Jeanette; Grummt, Ingrid

    2015-01-01

    Mitotic repression of rRNA synthesis requires inactivation of the RNA polymerase I (Pol I)-specific transcription factor SL1 by Cdk1/cyclin B-dependent phosphorylation of TAFI110 (TBP-associated factor 110) at a single threonine residue (T852). Upon exit from mitosis, T852 is dephosphorylated by Cdc14B, which is sequestered in nucleoli during interphase and is activated upon release from nucleoli at prometaphase. Mitotic repression of Pol I transcription correlates with transient nucleolar enrichment of the NAD+-dependent deacetylase SIRT1, which deacetylates another subunit of SL1, TAFI68. Hypoacetylation of TAFI68 destabilizes SL1 binding to the rDNA promoter, thereby impairing transcription complex assembly. Inhibition of SIRT1 activity alleviates mitotic repression of Pol I transcription if phosphorylation of TAFI110 is prevented. The results demonstrate that reversible phosphorylation of TAFI110 and acetylation of TAFI68 are key modifications that regulate SL1 activity and mediate fluctuations of pre-rRNA synthesis during cell cycle progression. PMID:26023773

  9. Post-veraison sunlight exposure induces MYB-mediated transcriptional regulation of anthocyanin and flavonol synthesis in berry skins of Vitis vinifera.

    PubMed

    Matus, José Tomás; Loyola, Rodrigo; Vega, Andrea; Peña-Neira, Alvaro; Bordeu, Edmundo; Arce-Johnson, Patricio; Alcalde, José Antonio

    2009-01-01

    Anthocyanins, flavan-3-ols, and flavonols are the three major classes of flavonoid compounds found in grape berry tissues. Several viticultural practices increase flavonoid content in the fruit, but the underlying genetic mechanisms responsible for these changes have not been completely deciphered. The impact of post-veraison sunlight exposure on anthocyanin and flavonol accumulation in grape berry skin and its relation to the expression of different transcriptional regulators known to be involved in flavonoid synthesis was studied. Treatments consisting of removing or moving aside the basal leaves which shade berry clusters were applied. Shading did not affect sugar accumulation or gene expression of HEXOSE TRANSPORTER 1, although in the leaf removal treatment, these events were retarded during the first weeks of ripening. Flavonols were the most drastically reduced flavonoids following shading and leaf removal treatments, related to the reduced expression of FLAVONOL SYNTHASE 4 and its putative transcriptional regulator MYB12. Anthocyanin accumulation and the expression of CHS2, LDOX, OMT, UFGT, MYBA1, and MYB5a genes were also affected. Other regulatory genes were less affected or not affected at all by these treatments. Non-transcriptional control mechanisms for flavonoid synthesis are also suggested, especially during the initial stages of ripening. Although berries from the leaf removal treatment received more light than shaded fruits, malvidin-3-glucoside and total flavonol content was reduced compared with the treatment without leaf removal. This work reveals that flavonol-related gene expression responds rapidly to field changes in light levels, as shown by the treatment in which shaded fruits were exposed to light in the late stages of ripening. Taken together, this study establishes MYB-specific responsiveness for the effect of sun exposure and sugar transport on flavonoid synthesis. PMID:19129169

  10. Post-veraison sunlight exposure induces MYB-mediated transcriptional regulation of anthocyanin and flavonol synthesis in berry skins of Vitis vinifera

    PubMed Central

    Matus, José Tomás; Loyola, Rodrigo; Vega, Andrea; Peña-Neira, Alvaro; Bordeu, Edmundo; Arce-Johnson, Patricio; Alcalde, José Antonio

    2009-01-01

    Anthocyanins, flavan-3-ols, and flavonols are the three major classes of flavonoid compounds found in grape berry tissues. Several viticultural practices increase flavonoid content in the fruit, but the underlying genetic mechanisms responsible for these changes have not been completely deciphered. The impact of post-veraison sunlight exposure on anthocyanin and flavonol accumulation in grape berry skin and its relation to the expression of different transcriptional regulators known to be involved in flavonoid synthesis was studied. Treatments consisting of removing or moving aside the basal leaves which shade berry clusters were applied. Shading did not affect sugar accumulation or gene expression of HEXOSE TRANSPORTER 1, although in the leaf removal treatment, these events were retarded during the first weeks of ripening. Flavonols were the most drastically reduced flavonoids following shading and leaf removal treatments, related to the reduced expression of FLAVONOL SYNTHASE 4 and its putative transcriptional regulator MYB12. Anthocyanin accumulation and the expression of CHS2, LDOX, OMT, UFGT, MYBA1, and MYB5a genes were also affected. Other regulatory genes were less affected or not affected at all by these treatments. Non-transcriptional control mechanisms for flavonoid synthesis are also suggested, especially during the initial stages of ripening. Although berries from the leaf removal treatment received more light than shaded fruits, malvidin-3-glucoside and total flavonol content was reduced compared with the treatment without leaf removal. This work reveals that flavonol-related gene expression responds rapidly to field changes in light levels, as shown by the treatment in which shaded fruits were exposed to light in the late stages of ripening. Taken together, this study establishes MYB-specific responsiveness for the effect of sun exposure and sugar transport on flavonoid synthesis. PMID:19129169

  11. Post-veraison sunlight exposure induces MYB-mediated transcriptional regulation of anthocyanin and flavonol synthesis in berry skins of Vitis vinifera.

    PubMed

    Matus, José Tomás; Loyola, Rodrigo; Vega, Andrea; Peña-Neira, Alvaro; Bordeu, Edmundo; Arce-Johnson, Patricio; Alcalde, José Antonio

    2009-01-01

    Anthocyanins, flavan-3-ols, and flavonols are the three major classes of flavonoid compounds found in grape berry tissues. Several viticultural practices increase flavonoid content in the fruit, but the underlying genetic mechanisms responsible for these changes have not been completely deciphered. The impact of post-veraison sunlight exposure on anthocyanin and flavonol accumulation in grape berry skin and its relation to the expression of different transcriptional regulators known to be involved in flavonoid synthesis was studied. Treatments consisting of removing or moving aside the basal leaves which shade berry clusters were applied. Shading did not affect sugar accumulation or gene expression of HEXOSE TRANSPORTER 1, although in the leaf removal treatment, these events were retarded during the first weeks of ripening. Flavonols were the most drastically reduced flavonoids following shading and leaf removal treatments, related to the reduced expression of FLAVONOL SYNTHASE 4 and its putative transcriptional regulator MYB12. Anthocyanin accumulation and the expression of CHS2, LDOX, OMT, UFGT, MYBA1, and MYB5a genes were also affected. Other regulatory genes were less affected or not affected at all by these treatments. Non-transcriptional control mechanisms for flavonoid synthesis are also suggested, especially during the initial stages of ripening. Although berries from the leaf removal treatment received more light than shaded fruits, malvidin-3-glucoside and total flavonol content was reduced compared with the treatment without leaf removal. This work reveals that flavonol-related gene expression responds rapidly to field changes in light levels, as shown by the treatment in which shaded fruits were exposed to light in the late stages of ripening. Taken together, this study establishes MYB-specific responsiveness for the effect of sun exposure and sugar transport on flavonoid synthesis.

  12. Glycosphingolipid synthesis inhibitor represses cytokine-induced activation of the Ras-MAPK pathway in embryonic neural precursor cells.

    PubMed

    Yanagisawa, Makoto; Nakamura, Kazuo; Taga, Tetsuya

    2005-09-01

    Neuronal and glial cells in the central nervous system are generated from common neural precursor cells during development. To evaluate the functions of glycosphingolipids (GSLs) in neural precursor cells, neuroepithelial cells (NECs) were prepared from mouse embryos (E14.5), and the effects of an inhibitor of glucosylceramide synthesis, D-threo-1-phenyl-2-decanoylamino-3-morpholino-1-propanol (PDMP), on NECs was investigated. In PDMP-treated NECs, the expression of GD3, a major ganglioside of NECs, disappeared. We found that basic fibroblast growth factor (bFGF)-induced proliferation and extracellular signal-regulated kinase (ERK) activation were repressed in PDMP-treated NECs. Leukemia inhibitory factor (LIF)-induced ERK activation was also abolished in PDMP-treated NECs, suggesting that PDMP specifically represses the Ras-MAPK pathway. bFGF-induced activation of the Ras-MAPK pathway in NECs is dependent on GSL-enriched microdomains, lipid rafts. The organization of lipid rafts and the distribution of Ras and Grb2-SOS in the microdomains were not affected. However, Ras activation was repressed in PDMP-treated NECs. In PDMP-treated NECs, some neuronal genes were up-regulated and glial genes were down-regulated. These results suggest that GSLs might be involved in the proliferation, survival, signal transduction and differentiation of NECs.

  13. Staphylococcus aureus RNAIII coordinately represses the synthesis of virulence factors and the transcription regulator Rot by an antisense mechanism

    PubMed Central

    Boisset, Sandrine; Geissmann, Thomas; Huntzinger, Eric; Fechter, Pierre; Bendridi, Nadia; Possedko, Maria; Chevalier, Clément; Helfer, Anne Catherine; Benito, Yvonne; Jacquier, Alain; Gaspin, Christine; Vandenesch, François; Romby, Pascale

    2007-01-01

    RNAIII is the intracellular effector of the quorum-sensing system in Staphylococcus aureus. It is one of the largest regulatory RNAs (514 nucleotides long) that are known to control the expression of a large number of virulence genes. Here, we show that the 3′ domain of RNAIII coordinately represses at the post-transcriptional level, the expression of mRNAs that encode a class of virulence factors that act early in the infection process. We demonstrate that the 3′ domain acts primarily as an antisense RNA and rapidly anneals to these mRNAs, forming long RNA duplexes. The interaction between RNAIII and the mRNAs results in repression of translation initiation and triggers endoribonuclease III hydrolysis. These processes are followed by rapid depletion of the mRNA pool. In addition, we show that RNAIII and its 3′ domain mediate translational repression of rot mRNA through a limited number of base pairings involving two loop–loop interactions. Since Rot is a transcriptional regulatory protein, we proposed that RNAIII indirectly acts on many downstream genes, resulting in the activation of the synthesis of several exoproteins. These data emphasize the multitude of regulatory steps affected by RNAIII and its 3′ domain in establishing a network of S. aureus virulence factors. PMID:17545468

  14. Genome-wide transcriptional profiles of the berry skin of two red grape cultivars (Vitis vinifera) in which anthocyanin synthesis is sunlight-dependent or -independent.

    PubMed

    Wu, Ben-Hong; Cao, Yue-Gang; Guan, Le; Xin, Hai-Ping; Li, Ji-Hu; Li, Shao-Hua

    2014-01-01

    Global gene expression was analyzed in the berry skin of two red grape cultivars, which can ('Jingyan') or cannot ('Jingxiu') synthesize anthocyanins after sunlight exclusion from fruit set until maturity. Gene transcripts responding to sunlight exclusion in 'Jingyan' were less complex than in 'Jingxiu'; 528 genes were induced and 383 repressed in the former, whereas 2655 genes were induced and 205 suppressed in 'Jingxiu'. They were regulated either in the same or opposing manner in the two cultivars, or in only one cultivar. In addition to VvUFGT and VvMYBA1, some candidate genes (e.g. AOMT, GST, and ANP) were identified which are probably involved in the differential responses of 'Jingxiu' and 'Jingyan' to sunlight exclusion. In addition, 26 MYB, 14 bHLH and 23 WD40 genes responded differently to sunlight exclusion in the two cultivars. Interestingly, all of the 189 genes classified as being relevant to ubiquitin-dependent protein degradation were down-regulated by sunlight exclusion in 'Jingxiu', but the majority (162) remained unchanged in 'Jingyan' berry skin. It would be of interest to determine the precise role of the ubiquitin pathway following sunlight exclusion, particularly the role of COP9 signalosome, cullins, RING-Box 1, and COP1-interacting proteins. Only a few genes in the light signal system were found to be regulated by sunlight exclusion in either or both cultivars. This study provides a valuable overview of the transcriptome changes and gives insight into the genetic background that may be responsible for sunlight-dependent versus -independent anthocyanin biosynthesis in berry skin.

  15. Pleiotropic effect of fluoranthene on anthocyanin synthesis and nodulation of Medicago sativa is reversed by the plant flavone luteolin

    SciTech Connect

    Wetzel, A.; Parniske, M.; Werner, D.

    1995-05-01

    The symbiosis between leguminous plants and soil bacteria of the genus Rhizobium is of considerable agronominal importance. Recently it has been found, that polycyclic aromatic hydrocarbons (PAHs; e.g. anthracene, phenanthrene, fluoranthene), occurring as ubiquitous environmental contaminants can inhibit nodulation of Medicago sativa. Fluoranthene is one of the dominant PAHs found in urban particulate matter, sewage sludge or beside motorways. Several organisms have been shown to be able to metabolize and mineralize fluoranthene but the uptake of fluoranthene is limited due to low solubility of fluoranthene in water and strong adsorption to humic substances in soil. Rhizobium meliloti cannot degrade fluoranthene. Toxic effects of fluoranthene on bacterial growth have never been observed. In contrast to their rhizobial symbiotic partners, alfalfa plants grown on a solidified fluoranthene-containing medium, exhibited symptoms of toxicity. They showed a dose-responsive decrease in shoot length and, if inoculated with R. meliloti, inhibition of nodule formation. Growth retardation is accompanied by a decrease in anthocyanin pigmentation of shoots, and an atypical accumulation of anthocyanins in roots. Plant flavonoids are known to play a central role in the signal exchange of the Legume-Rhizobium symbiosis. Phenylpropane derived compounds and flavonoids have been implicated in nodule development. Since fluoranthene impairs nodulation and induces the production of anthocyanins, it is possible that these events are causally linked via phenylpropanoid metabolism. These experiments attempt to overcome the inhibitory effects of fluoranthene by exogeneous application of the flavonoid luteolin. This paper demonstrates that luteolin antagonizes the fluoranthene mediated inhibition of nodule formation and prevents the accumulation of anthocyanins in roots. 29 refs., 4 figs., 1 tab.

  16. Mutations in Escherichia coli that relieve catabolite repression of tryptophanase synthesis. Tryptophanase promoter-like mutations.

    PubMed

    Ward, D F; Yudkin, M D

    1976-01-01

    From a strain lacking adenyl cyclase and the catabolite-sensitive gene activator protein, two mutants were isolated that can synthesize tryptophanase. Each mutation is extremely closely linked to the tryptophanase structural gene. The mutations differ from one another in the rate of synthesis of tryptophanase that they permit in the genetic background in which they were isolated; they differ from one another and also from the wild type in the maximum rate of synthesis of tryptophanase that they permit in a genetic background with intact adenyl cyclase and catabolite-sensitive gene activator protein. Both mutations appear to lie in the tryptophanase promoter.

  17. Anthocyanin kinetics are dependent on anthocyanin structure.

    PubMed

    Novotny, Janet A; Clevidence, Beverly A; Kurilich, Anne C

    2012-02-01

    The kinetics of anthocyanin metabolism was investigated in a human feeding trial. Volunteers (n 12) consumed purple carrots containing five anthocyanin forms: cyanidin-3-(xylose-glucose-galactoside), cyanidin-3-(xylose-galactoside), cyanidin-3-(xylose-sinapoyl-glucose-galactoside), cyanidin-3-(xylose-feruloyl-glucose-galactoside) and cyanidin-3-(xylose-coumuroyl-glucose-galactoside). The purple carrots were served as three different treatments in a crossover design with a 3-week washout between treatments. Purple carrot treatments were 250 g raw carrots, 250 g cooked carrots and 500 g cooked carrots. Serial blood and urine samples were collected for 8 and 24 h after the dose, respectively, and analysed for anthocyanins. Of the anthocyanin forms ingested, four were detected in plasma and urine: cyanidin-3-(xylose-glucose-galactoside), cyanidin-3-(xylose-galactoside), cyanidin-3-(xylose-sinapoyl-glucose-galactoside) and cyanidin-3-(xylose-feruloyl-glucose-galactoside). The time courses of plasma and urine anthocyanin contents were evaluated with compartmental modelling. Results showed that absorption, gastrointestinal transit and plasma elimination are dependent on anthocyanin structure. Absorption efficiencies of acylated compounds (cyanidin-3-(xylose-sinapoyl-glucose-galactoside) and cyanidin-3-(xylose-feruloyl-glucose-galactoside)) were less than those for non-acylated anthocyanins (cyanidin-3-(xylose-glucose-galactoside) and cyanidin-3-(xylose-galactoside)). The acylated anthocyanins exhibited a shorter half-life for gastrointestinal absorption than the non-acylated anthocyanins. Fractional elimination of non-acylated compounds was slower than that for acylated anthocyanins. These results provide the first information about the kinetics of individual anthocyanins in human beings.

  18. Anthocyanin kinetics are dependent on anthocyanin structure

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The kinetics of anthocyanin metabolism was investigated in a human feeding trial. Volunteers (n=12) consumed purple carrots containing five different anthocyanin forms: cyanidin-3-(2”-xylose-6”-glucose-galactoside), cyanidin-3-(2”-xylose-galactoside), cyanidin-3-(2”-xylose-6”-sinapoyl-glucose-galac...

  19. A bHLH transcription factor, DvIVS, is involved in regulation of anthocyanin synthesis in dahlia (Dahlia variabilis).

    PubMed

    Ohno, Sho; Hosokawa, Munetaka; Hoshino, Atsushi; Kitamura, Yoshikuni; Morita, Yasumasa; Park, Kyeung-Ii; Nakashima, Akiko; Deguchi, Ayumi; Tatsuzawa, Fumi; Doi, Motoaki; Iida, Shigeru; Yazawa, Susumu

    2011-10-01

    Dahlias (Dahlia variabilis) exhibit a wide range of flower colours because of accumulation of anthocyanin and other flavonoids in their ray florets. Two lateral mutants were used that spontaneously occurred in 'Michael J' (MJW) which has yellow ray florets with orange variegation. MJOr, a bud mutant producing completely orange ray florets, accumulates anthocyanins, flavones, and butein, and MJY, another mutant producing completely yellow ray florets, accumulates flavones and butein. Reverse transcription-PCR analysis showed that expression of chalcone synthase 1 (DvCHS1), flavanone 3-hydroxylase (DvF3H), dihydroflavonol 4-reductase (DvDFR), anthocyanidin synthase (DvANS), and DvIVS encoding a basic helix-loop-helix transcription factor were suppressed, whereas that of chalcone isomerase (DvCHI) and DvCHS2, another CHS with 69% nucleotide identity with DvCHS1, was not suppressed in the yellow ray florets of MJY. A 5.4 kb CACTA superfamily transposable element, transposable element of Dahlia variabilis 1 (Tdv1), was found in the fourth intron of the DvIVS gene of MJW and MJY, and footprints of Tdv1 were detected in the variegated flowers of MJW. It is shown that only one type of DvIVS gene was expressed in MJOr, whereas these plants are likely to have three types of the DvIVS gene. On the basis of these results, the mechanism regulating the formation of orange and yellow ray florets in dahlia is discussed. PMID:21765172

  20. Sustained therapeutic reversal of Huntington’s disease by transient repression of huntingtin synthesis

    PubMed Central

    Kordasiewicz, Holly B.; Stanek, Lisa M.; Wancewicz, Edward V.; Mazur, Curt; McAlonis, Melissa M.; Pytel, Kimberly A.; Artates, Jonathan W.; Weiss, Andreas; Cheng, Seng H.; Shihabuddin, Lamya S.; Hung, Gene; Bennett, C. Frank; Cleveland, Don W.

    2012-01-01

    SUMMARY The primary cause of Huntington’s disease (HD) is expression of huntingtin with a polyglutamine expansion. Despite an absence of consensus on the mechanism(s) of toxicity, diminishing the synthesis of mutant huntingtin will abate toxicity if delivered to the key affected cells. With antisense oligonucleotides (ASOs) that catalyze RNase H-mediated degradation of huntingtin mRNA, we demonstrate that transient infusion into the cerebral spinal fluid of symptomatic HD mouse models not only delays disease progression, but mediates a sustained reversal of disease phenotype that persists longer than the huntingtin knockdown. Reduction of wild type huntingtin, along with mutant huntingtin, produces the same sustained disease reversal. Similar ASO infusion into non-human primates is shown to effectively lower huntingtin in many brain regions targeted by HD pathology. Rather than requiring continuous treatment, our findings establish a therapeutic strategy for sustained HD disease reversal produced by transient ASO-mediated diminution of huntingtin synthesis. PMID:22726834

  1. Sustained therapeutic reversal of Huntington's disease by transient repression of huntingtin synthesis.

    PubMed

    Kordasiewicz, Holly B; Stanek, Lisa M; Wancewicz, Edward V; Mazur, Curt; McAlonis, Melissa M; Pytel, Kimberly A; Artates, Jonathan W; Weiss, Andreas; Cheng, Seng H; Shihabuddin, Lamya S; Hung, Gene; Bennett, C Frank; Cleveland, Don W

    2012-06-21

    The primary cause of Huntington's disease (HD) is expression of huntingtin with a polyglutamine expansion. Despite an absence of consensus on the mechanism(s) of toxicity, diminishing the synthesis of mutant huntingtin will abate toxicity if delivered to the key affected cells. With antisense oligonucleotides (ASOs) that catalyze RNase H-mediated degradation of huntingtin mRNA, we demonstrate that transient infusion into the cerebrospinal fluid of symptomatic HD mouse models not only delays disease progression but mediates a sustained reversal of disease phenotype that persists longer than the huntingtin knockdown. Reduction of wild-type huntingtin, along with mutant huntingtin, produces the same sustained disease reversal. Similar ASO infusion into nonhuman primates is shown to effectively lower huntingtin in many brain regions targeted by HD pathology. Rather than requiring continuous treatment, our findings establish a therapeutic strategy for sustained HD disease reversal produced by transient ASO-mediated diminution of huntingtin synthesis.

  2. A bHLH transcription factor, DvIVS, is involved in regulation of anthocyanin synthesis in dahlia (Dahlia variabilis)

    PubMed Central

    Ohno, Sho; Hosokawa, Munetaka; Hoshino, Atsushi; Kitamura, Yoshikuni; Morita, Yasumasa; Park, Kyeung-II; Nakashima, Akiko; Deguchi, Ayumi; Tatsuzawa, Fumi; Doi, Motoaki; Iida, Shigeru; Yazawa, Susumu

    2011-01-01

    Dahlias (Dahlia variabilis) exhibit a wide range of flower colours because of accumulation of anthocyanin and other flavonoids in their ray florets. Two lateral mutants were used that spontaneously occurred in ‘Michael J’ (MJW) which has yellow ray florets with orange variegation. MJOr, a bud mutant producing completely orange ray florets, accumulates anthocyanins, flavones, and butein, and MJY, another mutant producing completely yellow ray florets, accumulates flavones and butein. Reverse transcription–PCR analysis showed that expression of chalcone synthase 1 (DvCHS1), flavanone 3-hydroxylase (DvF3H), dihydroflavonol 4-reductase (DvDFR), anthocyanidin synthase (DvANS), and DvIVS encoding a basic helix–loop–helix transcription factor were suppressed, whereas that of chalcone isomerase (DvCHI) and DvCHS2, another CHS with 69% nucleotide identity with DvCHS1, was not suppressed in the yellow ray florets of MJY. A 5.4 kb CACTA superfamily transposable element, transposable element of Dahlia variabilis 1 (Tdv1), was found in the fourth intron of the DvIVS gene of MJW and MJY, and footprints of Tdv1 were detected in the variegated flowers of MJW. It is shown that only one type of DvIVS gene was expressed in MJOr, whereas these plants are likely to have three types of the DvIVS gene. On the basis of these results, the mechanism regulating the formation of orange and yellow ray florets in dahlia is discussed. PMID:21765172

  3. The rnc Gene Promotes Exopolysaccharide Synthesis and Represses the vicRKX Gene Expressions via MicroRNA-Size Small RNAs in Streptococcus mutans

    PubMed Central

    Mao, Meng-Ying; Yang, Ying-Ming; Li, Ke-Zeng; Lei, Lei; Li, Meng; Yang, Yan; Tao, Xiang; Yin, Jia-Xin; Zhang, Ru; Ma, Xin-Rong; Hu, Tao

    2016-01-01

    Dental caries is a biofilm-dependent disease that largely relies on the ability of Streptococcus mutans to synthesize exopolysaccharides. Although the rnc gene is suggested to be involved in virulence mechanisms in many other bacteria, the information regarding it in S. mutans is very limited. Here, using deletion or overexpression mutant assay, we demonstrated that rnc in S. mutans significantly positively regulated exopolysaccharide synthesis and further altered biofilm formation. Meanwhile, the cariogenecity of S. mutans was decreased by deletion of rnc in a specific pathogen-free (SPF) rat model. Interestingly, analyzing the expression at mRNA level, we found the downstream vic locus was repressed by rnc in S. mutans. Using deep sequencing and bioinformatics analysis, for the first time, three putative microRNA-size small RNAs (msRNAs) targeting vicRKX were predicted in S. mutans. The expression levels of these msRNAs were negatively correlated with vicRKX but positively correlated with rnc, indicating rnc probably repressed vicRKX expression through msRNAs at the post-transcriptional level. In all, the results present that rnc has a potential role in the regulation of exopolysaccharide synthesis and can affect vicRKX expressions via post-transcriptional repression in S. mutans. This study provides an alternative avenue for further research aimed at preventing caries. PMID:27242713

  4. Sugar-Hormone Cross-Talk in Anthocyanin Biosynthesis

    PubMed Central

    Das, Prasanta Kumar; Shin, Dong Ho; Choi, Sang-Bong; Park, Youn-Il

    2012-01-01

    Anthocyanins, a class of flavonoids, are recognized for their diverse functions in plant development and beneficial effects on human health. Many of the genes encoding anthocyanin biosynthesis enzymes and the transcription factors that activate or repress them have been identified. Regulatory proteins that control anthocyanin biosynthesis by regulating the expression of different structural genes at the transcriptional and post-transcriptional levels are differentially modulated by environmental and biological factors such as light, temperature, sugar and hormones. This minireview summarizes the recent findings contributing to our understanding of the role of sugars and hormones in the modulation of the anthocyanin biosynthesis pathway with emphasis on the coordinated regulation of the critical transcriptional R2R3-MYB/bHLH/WD40 (MBW) complex in Arabidopsis. PMID:22936387

  5. Extragenic suppressors of yeast glucose derepression mutants leading to constitutive synthesis of several glucose-repressible enzymes.

    PubMed

    Schüller, H J; Entian, K D

    1991-03-01

    Saccharomyces cerevisiae regulatory genes CAT1 and CAT3 constitute a positive control circuit necessary for derepression of gluconeogenic and disaccharide-utilizing enzymes. Mutations within these genes are epistatic to hxk2 and hex2, which cause defects in glucose repression. cat1 and cat3 mutants are unable to grow in the presence of nonfermentable carbon sources or maltose. Stable gene disruptions were constructed inside these genes, and the resulting growth deficiencies were used for selecting epistatic mutations. The revertants obtained were tested for glucose repression, and those showing altered regulatory properties were further investigated. Most revertants belonged to a single complementation group called cat4. This recessive mutation caused a defect in glucose repression of invertase, maltase, and iso-1-cytochrome c. Additionally, hexokinase activity was increased. Gluconeogenic enzymes are still normally repressible in cat4 mutants. The occurrence of recombination of cat1::HIS3 and cat3::LEU2 with some cat4 alleles allowed significant growth in the presence of ethanol, which could be attributed to a partial derepression of gluconeogenic enzymes. The cat4 complementation group was tested for allelism with hxk2, hex2, cat80, cid1, cyc8, and tup1 mutations, which were previously described as affecting glucose repression. Allelism tests and tetrad analysis clearly proved that the cat4 complementation group is a new class of mutant alleles affecting carbon source-dependent gene expression.

  6. Transient repression of the lac operon.

    PubMed

    Tyler, B; Loomis, W F; Magasanik, B

    1967-12-01

    Severe transient repression of constitutive or induced beta-galactosidase synthesis occurs upon the addition of glucose to cells of Escherichia coli growing on glycerol, succinic acid, or lactic acid. Only mutants particularily well adapted to growth on glucose exhibit this phenomenon when transferred to a glucose-containing medium. No change in ribonucleic acid (RNA) metabolism was observed during transient repression. We could show that transient repression is pleiotropic, affecting all products of the lac operon. It occurs in a mutant insensitive to catabolite repression. It is established much more rapidly than catabolite repression, and is elicited by glucose analogues that are phosphorylated but not further catabolized by the cell. Thus, transient repression is not a consequence of the exclusion of inducer from the cell, does not require catabolism of the added compound, and does not involve a gross change in RNA metabolism. We conclude that transient repression is distinct from catabolite repression. PMID:4864411

  7. Hydrogen-rich water reestablishes ROS homeostasis but exerts differential effects on anthocyanin synthesis in two varieties of radish sprouts under UV-A irradiation.

    PubMed

    Su, Nana; Wu, Qi; Liu, Yuanyuan; Cai, Jiangtao; Shen, Wenbiao; Xia, Kai; Cui, Jin

    2014-07-01

    The aims of the study were to investigate whether hydrogen gas (H2) was involved in regulation of anthocyanin biosynthesis in two contrasting radish (Raphanus sativus L.) varieties (low [LA] and high [HA] level of anthocyanin) under UV irradiation. The results showed that hydrogen-rich water (HRW) significantly blocked the UV-A-induced increase of H2O2 and O2(•-) accumulation, and enhanced the UV-A-induced increase of superoxide dismutase (SOD) and ascorbate peroxidase (APX) activities in LA and HA. Furthermore, UV-A-induced increase of anthocyanin and total phenols was further enhanced only in HA sprouts cotreated with HRW. LC-MS/MS analysis showed that five anthocyanidins existed in HA sprouts, but only two in LA sprouts. Meanwhile, the cyanidin was the most abundant anthocyanidin in HA, and the cyanidin was 2-fold higher cotreated with HRW than UV-A. Molecular analyses showed that the anthocyanin biosynthesis-related genes were upregulated significantly in both HA (in particular) and LA sprouts treated with HRW plus UV-A. These data imply that HRW reestablishes reactive oxygen species homeostasis in both LA and HA, but exerts different effects on anthocyanin accumulation between them under UV-A.

  8. A small non-coding RNA of the invasion gene island (SPI-1) represses outer membrane protein synthesis from the Salmonella core genome.

    PubMed

    Pfeiffer, Verena; Sittka, Alexandra; Tomer, Raju; Tedin, Karsten; Brinkmann, Volker; Vogel, Jörg

    2007-12-01

    The Salmonella pathogenicity island (SPI-1) encodes approximately 35 proteins involved in assembly of a type III secretion system (T3SS) which endows Salmonella with the ability to invade eukaryotic cells. We have discovered a novel SPI-1 gene, invR, which expresses an abundant small non-coding RNA (sRNA). The invR gene, which we identified in a global search for new Salmonella sRNA genes, is activated by the major SPI-1 transcription factor, HilD, under conditions that favour host cell invasion. The RNA chaperone, Hfq, is essential for the in vivo stability of the approximately 80 nt InvR RNA. Hfq binds InvR with high affinity in vitro, and InvR co-immunoprecipitates with FLAG epitope-tagged Hfq in Salmonella extracts. Surprisingly, deletion/overexpression of invR revealed no phenotype in SPI-1 regulation. In contrast, we find that InvR represses the synthesis of the abundant OmpD porin encoded by the Salmonella core genome. As invR is conserved in the early branching Salmonella bongori, we speculate that porin repression by InvR may have aided successful establishment of the SPI-1 T3SS after horizontal acquisition in the Salmonella lineage. This study identifies the first regulatory RNA of an enterobacterial pathogenicity island, and new roles for Hfq and HilD in SPI-1 gene expression.

  9. Heat shock represses rRNA synthesis by inactivation of TIF-IA and lncRNA-dependent changes in nucleosome positioning.

    PubMed

    Zhao, Zhongliang; Dammert, Marcel A; Hoppe, Sven; Bierhoff, Holger; Grummt, Ingrid

    2016-09-30

    Attenuation of ribosome biogenesis in suboptimal growth environments is crucial for cellular homeostasis and genetic integrity. Here, we show that shutdown of rRNA synthesis in response to elevated temperature is brought about by mechanisms that target both the RNA polymerase I (Pol I) transcription machinery and the epigenetic signature of the rDNA promoter. Upon heat shock, the basal transcription factor TIF-IA is inactivated by inhibition of CK2-dependent phosphorylations at Ser170/172. Attenuation of pre-rRNA synthesis in response to heat stress is accompanied by upregulation of PAPAS, a long non-coding RNA (lncRNA) that is transcribed in antisense orientation to pre-rRNA. PAPAS interacts with CHD4, the adenosine triphosphatase subunit of NuRD, leading to deacetylation of histones and movement of the promoter-bound nucleosome into a position that is refractory to transcription initiation. The results exemplify how stress-induced inactivation of TIF-IA and lncRNA-dependent changes of chromatin structure ensure repression of rRNA synthesis in response to thermo-stress.

  10. MicL, a new σE-dependent sRNA, combats envelope stress by repressing synthesis of Lpp, the major outer membrane lipoprotein

    PubMed Central

    Guo, Monica S.; Updegrove, Taylor B.; Gogol, Emily B.; Shabalina, Svetlana A.; Gross, Carol A.; Storz, Gisela

    2014-01-01

    In enteric bacteria, the transcription factor σE maintains membrane homeostasis by inducing synthesis of proteins involved in membrane repair and two small regulatory RNAs (sRNAs) that down-regulate synthesis of abundant membrane porins. Here, we describe the discovery of a third σE-dependent sRNA, MicL (mRNA-interfering complementary RNA regulator of Lpp), transcribed from a promoter located within the coding sequence of the cutC gene. MicL is synthesized as a 308-nucleotide (nt) primary transcript that is processed to an 80-nt form. Both forms possess features typical of Hfq-binding sRNAs but surprisingly target only a single mRNA, which encodes the outer membrane lipoprotein Lpp, the most abundant protein of the cell. We show that the copper sensitivity phenotype previously ascribed to inactivation of the cutC gene is actually derived from the loss of MicL and elevated Lpp levels. This observation raises the possibility that other phenotypes currently attributed to protein defects are due to deficiencies in unappreciated regulatory RNAs. We also report that σE activity is sensitive to Lpp abundance and that MicL and Lpp comprise a new σE regulatory loop that opposes membrane stress. Together MicA, RybB, and MicL allow σE to repress the synthesis of all abundant outer membrane proteins in response to stress. PMID:25030700

  11. Anthocyanidin synthase in non-anthocyanin-producing Caryophyllales species.

    PubMed

    Shimada, Setsuko; Inoue, Yoriko T; Sakuta, Masaaki

    2005-12-01

    Red colors in flowers are mainly produced by two types of pigments: anthocyanins and betacyanins. Although anthocyanins are widely distributed in higher plants, betacyanins have replaced anthocyanins in the Caryophyllales. There has been no report so far to find anthocyanins and betacyanins existing together within the same plant. This curious phenomenon has been examined from genetic and evolutionary perspectives, however nothing is known at the molecular level about the mutual exclusion of anthocyanins and betacyanins in higher plants. Here, we show that spinach (Spinacia oleracea) and pokeweed (Phytolacca americana), which are both members of the Caryophyllales, have functional anthocyanidin synthases (ANSs). The ability of ANSs of the Caryophyllales to oxidize trans-leucocyanidin to cyanidin is comparable to that of ANSs in anthocyanin-producing plants. Expression profiles reveal that, in spinach, dihydroflavonol 4-reductase (DFR) and ANS are not expressed in most tissues and organs, except seeds, in which ANS may contribute to proanthocyanidin synthesis. One possible explanation for the lack of anthocyanins in the Caryophyllales is the suppression or limited expression of the DFR and ANS.

  12. Anthocyanins Present in Some Tropical Fruits.

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Many tropical fruits are rich in anthocyanins, though limited information is available about the characterization and quantification of these anthocyanins. The identification of anthocyanin pigments in four tropical fruits was determined by ion trap mass spectrometry. Fruits studied included acero...

  13. Anthocyanin analyses of Vaccinium fruit dietary supplements

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Vaccinium fruit ingredients within dietary supplements were identified by comparisons with anthocyanin analyses of known Vaccinium profiles (demonstration of anthocyanin fingerprinting). Available Vaccinium supplements were purchased and analyzed; their anthocyanin profiles (based on HPLC separation...

  14. Expression of Genes Involved in Anthocyanin Biosynthesis in Relation to Anthocyanin, Proanthocyanidin, and Flavonol Levels during Bilberry Fruit Development1

    PubMed Central

    Jaakola, Laura; Määttä, Kaisu; Pirttilä, Anna Maria; Törrönen, Riitta; Kärenlampi, Sirpa; Hohtola, Anja

    2002-01-01

    The production of anthocyanins in fruit tissues is highly controlled at the developmental level. We have studied the expression of flavonoid biosynthesis genes during the development of bilberry (Vaccinium myrtillus) fruit in relation to the accumulation of anthocyanins, proanthocyanidins, and flavonols in wild berries and in color mutants of bilberry. The cDNA fragments of five genes from the flavonoid pathway, phenylalanine ammonia-lyase, chalcone synthase, flavanone 3-hydroxylase, dihydroflavonol 4-reductase, and anthocyanidin synthase, were isolated from bilberry using the polymerase chain reaction technique, sequenced, and labeled with a digoxigenin-dUTP label. These homologous probes were used for determining the expression of the flavonoid pathway genes in bilberries. The contents of anthocyanins, proanthocyanidins, and flavonols in ripening bilberries were analyzed with high-performance liquid chromatography-diode array detector and were identified using a mass spectrometry interface. Our results demonstrate a correlation between anthocyanin accumulation and expression of the flavonoid pathway genes during the ripening of berries. At the early stages of berry development, procyanidins and quercetin were the major flavonoids, but the levels decreased dramatically during the progress of ripening. During the later stages of ripening, the content of anthocyanins increased strongly and they were the major flavonoids in the ripe berry. The expression of flavonoid pathway genes in the color mutants of bilberry was reduced. A connection between flavonol and anthocyanin synthesis in bilberry was detected in this study and also in previous data collected from flavonol and anthocyanin analyses from other fruits. In accordance with this, models for the connection between flavonol and anthocyanin syntheses in fruit tissues are presented. PMID:12376640

  15. Active anthocyanin degradation in Brunfelsia calycina (yesterday--today--tomorrow) flowers.

    PubMed

    Vaknin, Hila; Bar-Akiva, Ayelet; Ovadia, Rinat; Nissim-Levi, Ada; Forer, Izhak; Weiss, David; Oren-Shamir, Michal

    2005-09-01

    Anthocyanins are the largest group of plant pigments responsible for colors ranging from red to violet and blue. The biosynthesis of anthocyanins, as part of the larger phenylpropanoid pathway, has been characterized in great detail. In contrast to the detailed molecular knowledge available on anthocyanin synthesis, very little is known about the stability and catabolism of anthocyanins in plants. In this study we present a preliminary characterization of active in planta degradation of anthocyanins, requiring novel mRNA and protein synthesis, in Brunfelsia calycina flowers. Brunfelsia is a unique system for this study, since the decrease in pigment concentration in its flowers (from dark purple to white) is extreme and rapid, and occurs at a specific and well-defined stage of flower development. Treatment of detached flowers with protein and mRNA synthesis inhibitors, at specific stages of flower development, prevented degradation. In addition, treatment of detached flowers with cytokinins delayed senescence without changing the rate of anthocyanin degradation, suggesting that degradation of anthocyanins is not part of the general senescence process of the flowers but rather a distinctive and specific pathway. Based on studies on anthocyanin degradation in wine and juices, peroxidases are reasonable candidates for the in vivo degradation. A significant increase in peroxidase activity was shown to correlate in time with the rate of anthocyanin degradation. An additional indication that oxidative enzymes are involved in the process is the fact that treatment of flowers with reducing agents, such as DTT and glutathione, caused inhibition of degradation. This study represents the first step in the elucidation of the molecular mechanism behind in vivo anthocyanin degradation in plants. PMID:15918029

  16. Active anthocyanin degradation in Brunfelsia calycina (yesterday--today--tomorrow) flowers.

    PubMed

    Vaknin, Hila; Bar-Akiva, Ayelet; Ovadia, Rinat; Nissim-Levi, Ada; Forer, Izhak; Weiss, David; Oren-Shamir, Michal

    2005-09-01

    Anthocyanins are the largest group of plant pigments responsible for colors ranging from red to violet and blue. The biosynthesis of anthocyanins, as part of the larger phenylpropanoid pathway, has been characterized in great detail. In contrast to the detailed molecular knowledge available on anthocyanin synthesis, very little is known about the stability and catabolism of anthocyanins in plants. In this study we present a preliminary characterization of active in planta degradation of anthocyanins, requiring novel mRNA and protein synthesis, in Brunfelsia calycina flowers. Brunfelsia is a unique system for this study, since the decrease in pigment concentration in its flowers (from dark purple to white) is extreme and rapid, and occurs at a specific and well-defined stage of flower development. Treatment of detached flowers with protein and mRNA synthesis inhibitors, at specific stages of flower development, prevented degradation. In addition, treatment of detached flowers with cytokinins delayed senescence without changing the rate of anthocyanin degradation, suggesting that degradation of anthocyanins is not part of the general senescence process of the flowers but rather a distinctive and specific pathway. Based on studies on anthocyanin degradation in wine and juices, peroxidases are reasonable candidates for the in vivo degradation. A significant increase in peroxidase activity was shown to correlate in time with the rate of anthocyanin degradation. An additional indication that oxidative enzymes are involved in the process is the fact that treatment of flowers with reducing agents, such as DTT and glutathione, caused inhibition of degradation. This study represents the first step in the elucidation of the molecular mechanism behind in vivo anthocyanin degradation in plants.

  17. Contributions of photosynthesis and phytochrome to the formation of anthocyanin in turnip seedlings.

    PubMed

    Schneider, M J; Stimson, W R

    1971-09-01

    Turnip seedlings (Brassica rapa L.) irradiated for 24 hours with radiation at 720 nanometers synthesize chlorophyll a and anthocyanin. Antimycin A and 2,4-dinitrophenol, which are known to reduce cyclic photophosphorylation, also reduce anthocyanin synthesis. Noncyclic photophosphorylation is inhibited by 3-(3,4-dichlorophenyl)-1,1-dimethylurea and o-phenanthroline. These compounds promote cyclic photophosphorylation and anthocyanin synthesis. On the basis of these findings it is suggested that the photomorphogenic response of anthocyanin synthesis in turnip seedlings arises in part through photosynthetic activity.Phytochrome involvement in turnip seedling photomorphogenesis is evidenced by the photoreversibility of anthocyanin synthesis in response to 5-minute irradiations with red or far red light. The inhibition of anthocyanin synthesis by 2,4-dinitrophenol does not arise from a destruction of phytochrome photoreversibility.It is suggested that plant photomorphogenic responses to prolonged far red irradiations arise through the photochemical activation of at least two pigment systems; namely, the photosynthetic pigments and phytochrome.

  18. Contributions of photosynthesis and phytochrome to the formation of anthocyanin in turnip seedlings.

    PubMed

    Schneider, M J; Stimson, W R

    1971-09-01

    Turnip seedlings (Brassica rapa L.) irradiated for 24 hours with radiation at 720 nanometers synthesize chlorophyll a and anthocyanin. Antimycin A and 2,4-dinitrophenol, which are known to reduce cyclic photophosphorylation, also reduce anthocyanin synthesis. Noncyclic photophosphorylation is inhibited by 3-(3,4-dichlorophenyl)-1,1-dimethylurea and o-phenanthroline. These compounds promote cyclic photophosphorylation and anthocyanin synthesis. On the basis of these findings it is suggested that the photomorphogenic response of anthocyanin synthesis in turnip seedlings arises in part through photosynthetic activity.Phytochrome involvement in turnip seedling photomorphogenesis is evidenced by the photoreversibility of anthocyanin synthesis in response to 5-minute irradiations with red or far red light. The inhibition of anthocyanin synthesis by 2,4-dinitrophenol does not arise from a destruction of phytochrome photoreversibility.It is suggested that plant photomorphogenic responses to prolonged far red irradiations arise through the photochemical activation of at least two pigment systems; namely, the photosynthetic pigments and phytochrome. PMID:16657788

  19. High-yield anthocyanin biosynthesis in engineered Escherichia coli.

    PubMed

    Yan, Yajun; Li, Zhen; Koffas, Mattheos A G

    2008-05-01

    Anthocyanins are red, purple, or blue plant water-soluble pigments. In the past two decades, anthocyanins have received extensive studies for their anti-oxidative, anti-inflammatory, anti-cancer, anti-obesity, anti-diabetic, and cardioprotective properties. In the present study, anthocyanin biosynthetic enzymes from different plant species were characterized and employed for pathway construction leading from inexpensive precursors such as flavanones and flavan-3-ols to anthocyanins in Escherichia coli. The recombinant E. coli cells successfully achieved milligram level production of two anthocyanins, pelargonidin 3-O-glucoside (0.98 mg/L) and cyanidin 3-O-gluside (2.07 mg/L) from their respective flavanone precursors naringenin and eriodictyol. Cyanidin 3-O-glucoside was produced at even higher yields (16.1 mg/L) from its flavan-3-ol, (+)-catechin precursor. Further studies demonstrated that availability of the glucosyl donor, UDP-glucose, was the key metabolic limitation, while product instability at normal pH was also identified as a barrier for production improvement. Therefore, various optimization strategies were employed for enhancing the homogenous synthesis of UDP-glucose in the host cells while at the same time stabilizing the final anthocyanin product. Such optimizations included culture medium pH adjustment, the creation of fusion proteins and the rational manipulation of E. coli metabolic network for improving the intracellular UDP-glucose metabolic pool. As a result, production of pelargonidin 3-O-glucoside at 78.9 mg/L and cyanidin 3-O-glucoside at 70.7 mg/L was achieved from their precursor flavan-3-ols without supplementation with extracellular UDP-glucose. These results demonstrate the efficient production of the core anthocyanins for the first time and open the possibility for their commercialization for pharmaceutical and nutraceutical applications.

  20. Tissue- and isoform-specific phytochrome regulation of light-dependent anthocyanin accumulation in Arabidopsis thaliana

    PubMed Central

    Warnasooriya, Sankalpi N; Porter, Katie J

    2011-01-01

    Phytochromes regulate light- and sucrose-dependent anthocyanin synthesis and accumulation in many plants. Mesophyll-specific phyA alone has been linked to the regulation of anthocyanin accumulation in response to far-red light in Arabidopsis thaliana. However, multiple mesophyll-localized phytochromes were implicated in the photoregulation of anthocyanin accumulation in red-light conditions. Here, we report a role for mesophyll-specific phyA in blue-light-dependent regulation of anthocyanin levels and novel roles for individual phy isoforms in the regulation of anthocyanin accumulation under red illumination. These results provide new insight into spatial- and isoform-specific regulation of pigmentation by phytochromes in A. thaliana. PMID:21455024

  1. Repression of global protein synthesis by Eif1a-like genes that are expressed specifically in the two-cell embryos and the transient Zscan4-positive state of embryonic stem cells.

    PubMed

    Hung, Sandy S C; Wong, Raymond C B; Sharov, Alexei A; Nakatake, Yuhki; Yu, Hong; Ko, Minoru S H

    2013-08-01

    Mouse embryonic stem (ES) cells are prototypical stem cells that remain undifferentiated in culture for long periods, yet maintain the ability to differentiate into essentially all cell types. Previously, we have reported that ES cells oscillate between two distinct states, which can be distinguished by the transient expression of Zscan4 genes originally identified for its specific expression in mouse two-cell stage embryos. Here, we report that the nascent protein synthesis is globally repressed in the Zscan4-positive state of ES cells, which is mediated by the transient expression of newly identified eukaryotic translation initiation factor 1A (Eif1a)-like genes. Eif1a-like genes, clustered on Chromosome 12, show the high sequence similarity to the Eifa1 and consist of 10 genes (Eif1al1-Eif1al10) and 9 pseudogenes (Eif1al-ps1-Eif1al-ps9). The analysis of the expressed sequence tag database showed that Eif1a-like genes are expressed mostly in the two-cell stage mouse embryos. Microarray analyses and quantitative real-time polymerase chain reaction analyses show that Eif1a-like genes are expressed specifically in the Zscan4-positive state of ES cells. These results indicate a novel mechanism to repress protein synthesis by Eif1a-like genes and a unique mode of protein synthesis regulation in ES cells, which undergo a transient and reversible repression of global protein synthesis in the Zscan4-positive state.

  2. Functional role of anthocyanins in high-light winter leaves of the evergreen herb Galax urceolata.

    PubMed

    Hughes, N M; Neufeld, H S; Burkey, K O

    2005-12-01

    High-light leaves of the evergreen herb Galax urceolata exhibit a striking color change from green to red during winter months due to anthocyanin synthesis in outermost mesophyll cells. Here we investigate three possible functions of this color change. To test the hypothesis that anthocyanins function as light attenuators, maximum photosystem II efficiency (F(v)/F(m)) of red and green leaves was measured during and after exposure to wavelengths either strongly or poorly absorbed by anthocyanin. To determine whether anthocyanins elevate radical-scavenging capacity, antioxidant activity of red and green leaves was assessed using the alpha,alpha-diphenyl-beta-picrylhydrazyl assay. Nonstructural carbohydrate levels were analyzed to test the hypothesis that anthocyanins function as a carbon sink. Declines in F(v)/F(m) under white and green light were significantly greater for green than red leaves, but were comparable under red light. Anthocyanin content positively correlated with antioxidant activity. Although levels of anthocyanins did not appear to be related to nonstructural carbohydrate concentration, high levels of sugars may be necessary for their photo-induction. Results suggest that anthocyanins function as light attenuators and may also contribute to the antioxidant pool in winter leaves.

  3. Subspecialization of R2R3-MYB Repressors for Anthocyanin and Proanthocyanidin Regulation in Forage Legumes

    PubMed Central

    Albert, Nick W.

    2015-01-01

    The synthesis of anthocyanin pigments and proanthocyanidins (condensed tannins) is regulated by MYB-bHLH-WDR (MBW) transcription factor complexes in all angiosperms studied to date. Tr-MYB133 and Tr-MYB134 were isolated from Trifolium repens and encode R2R3-MYBs that antagonize the activity of MBW activation complexes. These two genes are conserved in other legume species, and form two sub-clades within the larger anthocyanin/proanthocyanidin clade of MYB repressors. However, unlike petunia and Arabidopsis, these R2R3-MYB repressors do not prevent ectopic accumulation of anthocyanins or proanthocyanidins. Instead, they are expressed when anthocyanins or proanthocyanidins are being synthesized, and provide feedback regulation to MBW complexes. This feedback occurs because Tr-MYB133 and Tr-MYB134 are themselves regulated by MBW complexes. Tr-MYB133 is regulated by MBW complexes containing anthocyanin-related R2R3-MYB proteins (Tr-RED LEAF), while Tr-MYB134 is regulated by complexes containing the proanthocyanidin R2R3-MYBs (Tr-MYB14). Other features of the MBW gene regulation networks are also conserved within legumes, including the ability for the anthocyanin MBW complexes to activate the expression of the AN1/TT8 clade bHLH factor. The regulation of Tr-MYB133 and Tr-MYB134 by distinct, pathway-specific MBW complexes has resulted in subspecialization for controlling anthocyanin or proanthocyanidin synthesis. PMID:26779194

  4. Phytochrome-interacting factors PIF4 and PIF5 negatively regulate anthocyanin biosynthesis under red light in Arabidopsis seedlings.

    PubMed

    Liu, Zhongjuan; Zhang, Yongqiang; Wang, Jianfeng; Li, Ping; Zhao, Chengzhou; Chen, Yadi; Bi, Yurong

    2015-09-01

    Light is an important environmental factor inducing anthocyanin accumulation in plants. Phytochrome-interacting factors (PIFs) have been shown to be a family of bHLH transcription factors involved in light signaling in Arabidopsis. Red light effectively increased anthocyanin accumulation in wild-type Col-0, whereas the effects were enhanced in pif4 and pif5 mutants but impaired in overexpression lines PIF4OX and PIF5OX, indicating that PIF4 and PIF5 are both negative regulators for red light-induced anthocyanin accumulation. Consistently, transcript levels of several genes involved in anthocyanin biosynthesis and regulatory pathway, including CHS, F3'H, DFR, LDOX, PAP1 and TT8, were significantly enhanced in mutants pif4 and pif5 but decreased in PIF4OX and PIF5OX compared to in Col-0, indicating that PIF4 and PIF5 are transcriptional repressor of these gene. Transient expression assays revealed that PIF4 and PIF5 could repress red light-induced promoter activities of F3'H and DFR in Arabidopsis protoplasts. Furthermore, chromatin immunoprecipitation-quantitative PCR (ChIP-qPCR) test and electrophoretic mobility shift assay (EMSA) showed that PIF5 could directly bind to G-box motifs present in the promoter of DFR. Taken together, these results suggest that PIF4 and PIF5 negatively regulate red light-induced anthocyanin accumulation through transcriptional repression of the anthocyanin biosynthetic genes in Arabidopsis. PMID:26259175

  5. Phytochrome-interacting factors PIF4 and PIF5 negatively regulate anthocyanin biosynthesis under red light in Arabidopsis seedlings.

    PubMed

    Liu, Zhongjuan; Zhang, Yongqiang; Wang, Jianfeng; Li, Ping; Zhao, Chengzhou; Chen, Yadi; Bi, Yurong

    2015-09-01

    Light is an important environmental factor inducing anthocyanin accumulation in plants. Phytochrome-interacting factors (PIFs) have been shown to be a family of bHLH transcription factors involved in light signaling in Arabidopsis. Red light effectively increased anthocyanin accumulation in wild-type Col-0, whereas the effects were enhanced in pif4 and pif5 mutants but impaired in overexpression lines PIF4OX and PIF5OX, indicating that PIF4 and PIF5 are both negative regulators for red light-induced anthocyanin accumulation. Consistently, transcript levels of several genes involved in anthocyanin biosynthesis and regulatory pathway, including CHS, F3'H, DFR, LDOX, PAP1 and TT8, were significantly enhanced in mutants pif4 and pif5 but decreased in PIF4OX and PIF5OX compared to in Col-0, indicating that PIF4 and PIF5 are transcriptional repressor of these gene. Transient expression assays revealed that PIF4 and PIF5 could repress red light-induced promoter activities of F3'H and DFR in Arabidopsis protoplasts. Furthermore, chromatin immunoprecipitation-quantitative PCR (ChIP-qPCR) test and electrophoretic mobility shift assay (EMSA) showed that PIF5 could directly bind to G-box motifs present in the promoter of DFR. Taken together, these results suggest that PIF4 and PIF5 negatively regulate red light-induced anthocyanin accumulation through transcriptional repression of the anthocyanin biosynthetic genes in Arabidopsis.

  6. Menin represses tumorigenesis via repressing cell proliferation

    PubMed Central

    Wu, Ting; Hua, Xianxin

    2011-01-01

    Multiple endocrine neoplasia type 1 (MEN1) results from mutations in the tumor suppressor gene, MEN1, which encodes nuclear protein menin. Menin is important for suppressing tumorigenesis in various endocrine and certain non-endocrine tissues. Although menin suppresses MEN1 through a variety of mechanisms including regulating apoptosis and DNA repair, the role of menin in regulating cell proliferation is one of the best-studied functions. Here, we focus on reviewing various mechanisms underlying menin-mediated inhibition of cell proliferation. Menin inhibits cell proliferation to repress MEN1 through multiple mechanisms. 1) Menin interacts with various histonemodifying enzymes, such as MLL, EZH2 and HDACs, to affect gene transcription, leading to repression of cell proliferation. 2) Menin also interacts with various transcription factors, such as JunD, NF-κB, PPARγ and VDR, to induce or suppress gene transcription. As these various transcription factors are known to regulate cell proliferation, their interaction with menin may be relevant to menin's role in inhibiting cell proliferation. 3) Menin inhibits cell proliferation via TGF-β signaling and Wnt/β-catenin signaling pathways. 4) Menin represses certain pro-proliferative factors involved in endocrine tumors such as IGFBP-2, IGF2 and PTHrP to repress cell proliferation. 5) Menin affects cell cycle progression to inhibit cell proliferation. This review is helpful in our understanding of the comprehensive mechanisms whereby menin represses MEN1 through inhibiting cell proliferation. PMID:22016823

  7. Anthocyanins facilitate tungsten accumulation in Brassica

    SciTech Connect

    Hale, K.L.

    2002-11-01

    Accumulation of molybdenum in Brassica was recently found to be correlated with anthocyanin content, involving the formation of a blue complex. Here the role of anthocyanins in tungsten sequestration was investigated using three species of Brassica: B. rapa (cv. Fast plants), B. juncea (Indian mustard) and B. oleracea (red cabbage). Seedlings of B. rapa and B. juncea turned blue when supplied with colourless tungstate. The blue compound co-localized with anthocyanins in the peripheral cell layers, and the degree of blueness was correlated with anthocyanin content. The direct involvement of anthocyanins in the blue coloration was evident when purified anthocyanins showed a colour change from pink to blue in vitro upon addition of tungstate, over a wide pH range. Anthocyanin production was upregulated 3-fold by W in B. juncea, possibly reflecting a function for anthocyanins in W tolerance or sequestration. The presence of anthocyanins facilitated W accumulation in B. rapa: anthocyanin-containing seedlings accumulated 3-fold more W than an anthocyaninless mutant. There was no correlation between anthocyanin content and W tolerance under these conditions. The nature of the interaction between anthocyanins and tungstate was investigated. X-ray absorption spectroscopy showed no change in the local chemical environment of Wupon uptake of tungstate by the plant; HPLC analysis of purified anthocyanin with or without tungstate showed no peak shift after metal treatment.

  8. Mulberry anthocyanin biotransformation by intestinal probiotics.

    PubMed

    Cheng, Jing-Rong; Liu, Xue-Ming; Chen, Zhi-Yi; Zhang, You-Sheng; Zhang, Ye-Hui

    2016-12-15

    This study was designed to evaluate mulberry anthocyanins bioconversion traits for intestinal probiotics. Five intestinal beneficial bacteria were incubated with mulberry anthocyanins under anaerobic conditions at 37°C, and bacterial β-glucosidase activity and anthocyanin level were determined. Results demonstrated that all strains could convert mulberry anthocyanins to some extent. With high β-glucosidase production capacity, Streptococcus thermophiles GIM 1.321 and Lactobacillus plantarum GIM 1.35 degraded mulberry anthocyanins by 46.17% and 43.62%, respectively. Mulberry anthocyanins were mainly biotransformed to chlorogenic acid, crypto-chlorogenic acid, caffeic acid, and ferulic acid during the anaerobic process. Non-enzymatic deglycosylation of anthocyanins also occurred and approximately 19.42% of the anthocyanins were degraded within 48h by this method. PMID:27451240

  9. Light-Induced Expression of a MYB Gene Regulates Anthocyanin Biosynthesis in Red Apples1

    PubMed Central

    Takos, Adam M.; Jaffé, Felix W.; Jacob, Steele R.; Bogs, Jochen; Robinson, Simon P.; Walker, Amanda R.

    2006-01-01

    Anthocyanins are secondary metabolites found in higher plants that contribute to the colors of flowers and fruits. In apples (Malus domestica Borkh.), several steps of the anthocyanin pathway are coordinately regulated, suggesting control by common transcription factors. A gene encoding an R2R3 MYB transcription factor was isolated from apple (cv Cripps' Pink) and designated MdMYB1. Analysis of the deduced amino acid sequence suggests that this gene encodes an ortholog of anthocyanin regulators in other plants. The expression of MdMYB1 in both Arabidopsis (Arabidopsis thaliana) plants and cultured grape cells induced the ectopic synthesis of anthocyanin. In the grape (Vitis vinifera) cells MdMYB1 stimulated transcription from the promoters of two apple genes encoding anthocyanin biosynthetic enzymes. In ripening apple fruit the transcription of MdMYB1 was correlated with anthocyanin synthesis in red skin sectors of fruit. When dark-grown fruit were exposed to sunlight, MdMYB1 transcript levels increased over several days, correlating with anthocyanin synthesis in the skin. MdMYB1 gene transcripts were more abundant in red skin apple cultivars compared to non-red skin cultivars. Several polymorphisms were identified in the promoter of MdMYB1. A derived cleaved amplified polymorphic sequence marker designed to one of these polymorphisms segregated with the inheritance of skin color in progeny from a cross of an unnamed red skin selection (a sibling of Cripps' Pink) and the non-red skin cultivar Golden Delicious. We conclude that MdMYB1 coordinately regulates genes in the anthocyanin pathway and the expression level of this regulator is the genetic basis for apple skin color. PMID:17012405

  10. Sugar Maple Phenology: Anthocyanin Production During Leaf Senescence

    NASA Astrophysics Data System (ADS)

    Lindgren, E.; Rock, B.

    2007-12-01

    The Northeastern United States is known for its brilliant fall foliage colors. Foliage is responsible for a billion dollar tourism industry. Many comment that past years have not resulted in the amazing color displays seen historically. As sugar maple trees senesce they contribute bright red leaves to the mural of oranges, yellows, and greens. The pigment that produces the red color, anthocyanin, is synthesized in the fall as chlorophyll slowly degrades. Remote sensing data from LandSat during fall senescence can help investigate this event by quantifying color change and intensity. This data can then be compared to ground validation efforts in several study plots. The results will help answer the question, "Why do leaves turn red?" One hypothesis is that this pigment acts as a photoprotectant and screens leaves from UV light. It is possible that an increase in tropospheric ozone has negatively affected fall foliage due to the increased reflection of UV light before it reaches the trees; thereby reducing the leaves need to produce anthocyanin. Another hypothesis is that production of anthocyanin is linked to temperature, with maximum synthesis occurring during cold evenings and moderate days. Temperature changes caused by climate change could also be affecting anthocyanin. Through observing these changes by remote sensing and ground experiments, more can be learned about this phenological stage and why it happens.

  11. Searching for repressed memory.

    PubMed

    McNally, Richard J

    2012-01-01

    This chapter summarizes the work of my research group on adults who report either repressed, recovered, or continuous memories of childhood sexual abuse (CSA) or who report no history of CSA. Adapting paradigms from cognitive psychology, we tested hypotheses inspired by both the "repressed memory" and "false memory" perspectives on recovered memories of CSA. We found some evidence for the false memory perspective, but no evidence for the repressed memory perspective. However, our work also suggests a third perspective on recovered memories that does not require the concept of repression. Some children do not understand their CSA when it occurs, and do not experience terror. Years later, they recall the experience, and understanding it as abuse, suffer intense distress. The memory failed to come to mind for years, partly because the child did not encode it as terrifying (i.e., traumatic), not because the person was unable to recall it.

  12. Insight into the role of anthocyanin biosynthesis-related genes in Medicago truncatula mutants impaired in pigmentation in leaves.

    PubMed

    Carletti, Giorgia; Lucini, Luigi; Busconi, Matteo; Marocco, Adriano; Bernardi, Jamila

    2013-09-01

    Flavonoids are the most common antioxidant compounds produced in plants. In this study, two wild types and two independent mutants of Medicago truncatula with altered anthocyanin content in leaves were characterized at the phenotype, metabolite profile, gene structure and transcript levels. Flavonoid profiles showed conserved levels of dihydroflavonols, leucoanthocyanidins and flavonols, while anthocyanidin, anthocyanin and isoflavone levels were lower in the mutants (up to 90% less) compared with the wild types. Genes encoding key enzymes of the anthocyanin pathway and transcriptional factors were analyzed by RT-PCR. Genes involved in the later steps of the anthocyanin pathway (dihydrokaempferol reductase 2, UDP-glucose:anthocyanin 3-O-glucosyltransferase and glutathione S-transferase) were found under-expressed in both mutants. Dihydrokaempferol reductase 1 was downregulated two-fold in the anthocyanin-less mutant while the UDP-glucose:anthocyanin 5-O-glucosyltransferase was strongly repressed only in the mutant with low pigmentation, suggesting a different regulation in the two genotypes. The common feature was that the first enzymes of the flavonoid biosynthesis pathway were not altered in rate of expression. A very high reduction in transcript accumulation was also found for two homologous R2R3 MYB genes, namely MtMYBA and AN2, suggesting that these genes have a role in anthocyanin accumulation in leaves. More evidence was found on analyzing their nucleotide sequence: several SNPs, insertions and deletions in the coding and non-coding regions of both MYB genes were found between mutants and wild types that could influence anthocyanin biosynthesis. Moreover, a subfamily of eight MYB genes with a high homology to MtMYBA was discovered in tandem on chromosome 5 of M. truncatula.

  13. Yeast carbon catabolite repression.

    PubMed

    Gancedo, J M

    1998-06-01

    Glucose and related sugars repress the transcription of genes encoding enzymes required for the utilization of alternative carbon sources; some of these genes are also repressed by other sugars such as galactose, and the process is known as catabolite repression. The different sugars produce signals which modify the conformation of certain proteins that, in turn, directly or through a regulatory cascade affect the expression of the genes subject to catabolite repression. These genes are not all controlled by a single set of regulatory proteins, but there are different circuits of repression for different groups of genes. However, the protein kinase Snf1/Cat1 is shared by the various circuits and is therefore a central element in the regulatory process. Snf1 is not operative in the presence of glucose, and preliminary evidence suggests that Snf1 is in a dephosphorylated state under these conditions. However, the enzymes that phosphorylate and dephosphorylate Snf1 have not been identified, and it is not known how the presence of glucose may affect their activity. What has been established is that Snf1 remains active in mutants lacking either the proteins Grr1/Cat80 or Hxk2 or the Glc7 complex, which functions as a protein phosphatase. One of the main roles of Snf1 is to relieve repression by the Mig1 complex, but it is also required for the operation of transcription factors such as Adr1 and possibly other factors that are still unidentified. Although our knowledge of catabolite repression is still very incomplete, it is possible in certain cases to propose a partial model of the way in which the different elements involved in catabolite repression may be integrated.

  14. Anthocyanin analyses of Vaccinium fruit dietary supplements.

    PubMed

    Lee, Jungmin

    2016-09-01

    Vaccinium fruit ingredients within dietary supplements were identified by comparisons with anthocyanin analyses of known Vaccinium profiles (demonstration of anthocyanin fingerprinting). Available Vaccinium supplements were purchased and analyzed, their anthocyanin profiles (based on high-performance liquid chromatography [HPLC] separation) indicated if products' fruit origin listings were authentic. Over 30% of the Vaccinium fruit (cranberry, lingonberry, bilberry, and blueberry; 14 of 45) products available as dietary supplements did not contain the fruit listed as ingredients. Six supplements contained no anthocyanins. Five others had contents differing from labeled fruit (e.g., bilberry capsules containing Andean blueberry fruit). Of the samples that did contain the specified fruit (n = 27), anthocyanin content ranged from 0.04 to 14.37 mg per capsule, tablet, or teaspoon (5 g). Approaches to utilizing anthocyanins in assessment of sample authenticity, and a discussion of the challenges with anthocyanin profiles in quality control are both presented. PMID:27625778

  15. Low-temperature conditioning of "seed" cloves enhances the expression of phenolic metabolism related genes and anthocyanin content in 'Coreano' garlic (Allium sativum) during plant development.

    PubMed

    Dufoo-Hurtado, Miguel D; Zavala-Gutiérrez, Karla G; Cao, Cong-Mei; Cisneros-Zevallos, Luis; Guevara-González, Ramón G; Torres-Pacheco, Irineo; Vázquez-Barrios, M Estela; Rivera-Pastrana, Dulce M; Mercado-Silva, Edmundo M

    2013-11-01

    Low-temperature conditioning of garlic "seed" cloves accelerated the development of the crop cycle, decreased plant growth, and increased the synthesis of phenolic compounds and anthocyanins in the outer scale leaves of the bulbs at harvest time, leading to 3-fold content increase compared with those conditioned at room temperature. Cold conditioning of "seed" cloves also altered the anthocyanin profile during bulb development and at harvest. Two new anthocyanins are reported for the first time in garlic. The high phenolics and anthocyanin contents in bulbs of plants generated from "seed" cloves conditioned at 5 °C for 5 weeks were preceded by overexpression of some putative genes of the phenolic metabolism [6-fold for phenylalanine ammonia lyase (PAL)] and anthocyanin synthesis [1-fold for UDP-sugar:flavonoid 3-O-glycosyltransferase (UFGT)] compared with those conditioned at room temperature.

  16. From classical psychodynamics to evidence synthesis: the motif of repression and a contemporary understanding of a key mediatory mechanism in psychosis.

    PubMed

    Fleming, Mick P; Martin, Colin R

    2012-06-01

    The stress vulnerability model has proven to be a politically important model for two reasons. It has provided the framework that defines a temporal and dynamic process whereby a person's uniquely determined biopsychosocial vulnerability to schizophrenia symptoms interacts with his or her capacity to manage stress and the amount and type of stress experienced in such a way that the person experiences schizophrenia symptoms. Second, the development of this framework promoted the notion of inherited and acquired vulnerability. Implicit was that vulnerability was individually determined and that there was a role for psychosocial factors in the development/maintenance of schizophrenia symptoms. This proved to be a catalyst for the development of studies implicating psychosocial factors in the etiology of schizophrenia symptoms. Studies derived from cognitive-behavioral theories have proven the most successful in identifying thinking patterns, emotional disturbances, and neurocognitive and defensive vulnerability factors inherent in the development of schizophrenia symptoms. Historically, within the psychoanalytic school there has been debate regarding the role of repressive coping mechanisms in schizophrenia development. Psychoanalytic theories have always appeared incapable of providing etiologic explanations of schizophrenia symptoms, with the possible exception of Melanie Klein, than other more salient psychosocial schools. Mechanisms within the process of repressive coping are consistent with evidence and mechanisms supporting the stress vulnerability models and existing cognitive-behavioral theories regarding development of paranoid delusions. These mechanisms are less consistent with social cognitive explanations of schizophrenia symptoms.

  17. From classical psychodynamics to evidence synthesis: the motif of repression and a contemporary understanding of a key mediatory mechanism in psychosis.

    PubMed

    Fleming, Mick P; Martin, Colin R

    2012-06-01

    The stress vulnerability model has proven to be a politically important model for two reasons. It has provided the framework that defines a temporal and dynamic process whereby a person's uniquely determined biopsychosocial vulnerability to schizophrenia symptoms interacts with his or her capacity to manage stress and the amount and type of stress experienced in such a way that the person experiences schizophrenia symptoms. Second, the development of this framework promoted the notion of inherited and acquired vulnerability. Implicit was that vulnerability was individually determined and that there was a role for psychosocial factors in the development/maintenance of schizophrenia symptoms. This proved to be a catalyst for the development of studies implicating psychosocial factors in the etiology of schizophrenia symptoms. Studies derived from cognitive-behavioral theories have proven the most successful in identifying thinking patterns, emotional disturbances, and neurocognitive and defensive vulnerability factors inherent in the development of schizophrenia symptoms. Historically, within the psychoanalytic school there has been debate regarding the role of repressive coping mechanisms in schizophrenia development. Psychoanalytic theories have always appeared incapable of providing etiologic explanations of schizophrenia symptoms, with the possible exception of Melanie Klein, than other more salient psychosocial schools. Mechanisms within the process of repressive coping are consistent with evidence and mechanisms supporting the stress vulnerability models and existing cognitive-behavioral theories regarding development of paranoid delusions. These mechanisms are less consistent with social cognitive explanations of schizophrenia symptoms. PMID:22359200

  18. An Intracellular Laccase Is Responsible for Epicatechin-Mediated Anthocyanin Degradation in Litchi Fruit Pericarp.

    PubMed

    Fang, Fang; Zhang, Xue-lian; Luo, Hong-hui; Zhou, Jia-jian; Gong, Yi-hui; Li, Wen-jun; Shi, Zhao-wan; He, Quan; Wu, Qing; Li, Lu; Jiang, Lin-lin; Cai, Zhi-gao; Oren-Shamir, Michal; Zhang, Zhao-qi; Pang, Xue-qun

    2015-12-01

    In contrast to the detailed molecular knowledge available on anthocyanin synthesis, little is known about its catabolism in plants. Litchi (Litchi chinensis) fruit lose their attractive red color soon after harvest. The mechanism leading to quick degradation of anthocyanins in the pericarp is not well understood. An anthocyanin degradation enzyme (ADE) was purified to homogeneity by sequential column chromatography, using partially purified anthocyanins from litchi pericarp as a substrate. The purified ADE, of 116 kD by urea SDS-PAGE, was identified as a laccase (ADE/LAC). The full-length complementary DNA encoding ADE/LAC was obtained, and a polyclonal antibody raised against a deduced peptide of the gene recognized the ADE protein. The anthocyanin degradation function of the gene was confirmed by its transient expression in tobacco (Nicotiana benthamiana) leaves. The highest ADE/LAC transcript abundance was in the pericarp in comparison with other tissues, and was about 1,000-fold higher than the polyphenol oxidase gene in the pericarp. Epicatechin was found to be the favorable substrate for the ADE/LAC. The dependence of anthocyanin degradation by the enzyme on the presence of epicatechin suggests an ADE/LAC epicatechin-coupled oxidation model. This model was supported by a dramatic decrease in epicatechin content in the pericarp parallel to anthocyanin degradation. Immunogold labeling transmission electron microscopy suggested that ADE/LAC is located mainly in the vacuole, with essential phenolic substances. ADE/LAC vacuolar localization, high expression levels in the pericarp, and high epicatechin-dependent anthocyanin degradation support its central role in pigment breakdown during pericarp browning.

  19. An Intracellular Laccase Is Responsible for Epicatechin-Mediated Anthocyanin Degradation in Litchi Fruit Pericarp.

    PubMed

    Fang, Fang; Zhang, Xue-lian; Luo, Hong-hui; Zhou, Jia-jian; Gong, Yi-hui; Li, Wen-jun; Shi, Zhao-wan; He, Quan; Wu, Qing; Li, Lu; Jiang, Lin-lin; Cai, Zhi-gao; Oren-Shamir, Michal; Zhang, Zhao-qi; Pang, Xue-qun

    2015-12-01

    In contrast to the detailed molecular knowledge available on anthocyanin synthesis, little is known about its catabolism in plants. Litchi (Litchi chinensis) fruit lose their attractive red color soon after harvest. The mechanism leading to quick degradation of anthocyanins in the pericarp is not well understood. An anthocyanin degradation enzyme (ADE) was purified to homogeneity by sequential column chromatography, using partially purified anthocyanins from litchi pericarp as a substrate. The purified ADE, of 116 kD by urea SDS-PAGE, was identified as a laccase (ADE/LAC). The full-length complementary DNA encoding ADE/LAC was obtained, and a polyclonal antibody raised against a deduced peptide of the gene recognized the ADE protein. The anthocyanin degradation function of the gene was confirmed by its transient expression in tobacco (Nicotiana benthamiana) leaves. The highest ADE/LAC transcript abundance was in the pericarp in comparison with other tissues, and was about 1,000-fold higher than the polyphenol oxidase gene in the pericarp. Epicatechin was found to be the favorable substrate for the ADE/LAC. The dependence of anthocyanin degradation by the enzyme on the presence of epicatechin suggests an ADE/LAC epicatechin-coupled oxidation model. This model was supported by a dramatic decrease in epicatechin content in the pericarp parallel to anthocyanin degradation. Immunogold labeling transmission electron microscopy suggested that ADE/LAC is located mainly in the vacuole, with essential phenolic substances. ADE/LAC vacuolar localization, high expression levels in the pericarp, and high epicatechin-dependent anthocyanin degradation support its central role in pigment breakdown during pericarp browning. PMID:26514808

  20. Expression and Anthocyanin Biosynthesis-Modulating Potential of Sweet Cherry (Prunus avium L.) MYB10 and bHLH Genes.

    PubMed

    Starkevič, Pavel; Paukštytė, Jurgita; Kazanavičiūtė, Vaiva; Denkovskienė, Erna; Stanys, Vidmantas; Bendokas, Vidmantas; Šikšnianas, Tadeušas; Ražanskienė, Aušra; Ražanskas, Raimundas

    2015-01-01

    Anthocyanins are essential contributors to fruit coloration, an important quality feature and a breed determining trait of a sweet cherry fruit. It is well established that the biosynthesis of anthocyanins is regulated by an interplay of specific transcription factors belonging to MYB and bHLH families accompanied by a WD40 protein. In this study, we isolated and analyzed PaWD40, PabHLH3, PabHLH33, and several closely related MYB10 gene variants from different cultivars of sweet cherry, analyzed their expression in fruits with different anthocyanin levels at several developmental stages, and determined their capabilities to modulate anthocyanin synthesis in leaves of two Nicotiana species. Our results indicate that transcription level of variant PaMYB10.1-1 correlates with fruit coloration, but anthocyanin synthesis in Nicotiana was induced by another variant, PaMYB10.1-3, which is moderately expressed in fruits. The analysis of two fruit-expressed bHLH genes revealed that PabHLH3 enhances MYB-induced anthocyanin synthesis, whereas PabHLH33 has strong inhibitory properties. PMID:25978735

  1. Expression and Anthocyanin Biosynthesis-Modulating Potential of Sweet Cherry (Prunus avium L.) MYB10 and bHLH Genes

    PubMed Central

    Starkevič, Pavel; Paukštytė, Jurgita; Kazanavičiūtė, Vaiva; Denkovskienė, Erna; Stanys, Vidmantas; Bendokas, Vidmantas; Šikšnianas, Tadeušas; Ražanskienė, Aušra; Ražanskas, Raimundas

    2015-01-01

    Anthocyanins are essential contributors to fruit coloration, an important quality feature and a breed determining trait of a sweet cherry fruit. It is well established that the biosynthesis of anthocyanins is regulated by an interplay of specific transcription factors belonging to MYB and bHLH families accompanied by a WD40 protein. In this study, we isolated and analyzed PaWD40, PabHLH3, PabHLH33, and several closely related MYB10 gene variants from different cultivars of sweet cherry, analyzed their expression in fruits with different anthocyanin levels at several developmental stages, and determined their capabilities to modulate anthocyanin synthesis in leaves of two Nicotiana species. Our results indicate that transcription level of variant PaMYB10.1-1 correlates with fruit coloration, but anthocyanin synthesis in Nicotiana was induced by another variant, PaMYB10.1-3, which is moderately expressed in fruits. The analysis of two fruit-expressed bHLH genes revealed that PabHLH3 enhances MYB-induced anthocyanin synthesis, whereas PabHLH33 has strong inhibitory properties. PMID:25978735

  2. Anthocyanins do not influence long-chain n-3 fatty acid status: studies in cells, rodents and humans☆

    PubMed Central

    Vauzour, David; Tejera, Noemi; O'Neill, Colette; Booz, Valeria; Jude, Baptiste; Wolf, Insa M.A.; Rigby, Neil; Silvan, Jose Manuel; Curtis, Peter J.; Cassidy, Aedin; de Pascual-Teresa, Sonia; Rimbach, Gerald; Minihane, Anne Marie

    2015-01-01

    Increased tissue status of the long-chain n-3 polyunsaturated fatty acids (LC n-3 PUFA), eicosapentaenoic (EPA) and docosahexaenoic acid (DHA) is associated with cardiovascular and cognitive benefits. Limited epidemiological and animal data suggest that flavonoids, and specifically anthocyanins, may increase EPA and DHA levels, potentially by increasing their synthesis from the shorter-chain n-3 PUFA, α-linolenic acid. Using complimentary cell, rodent and human studies we investigated the impact of anthocyanins and anthocyanin-rich foods/extracts on plasma and tissue EPA and DHA levels and on the expression of fatty acid desaturase 2 (FADS2), which represents the rate limiting enzymes in EPA and DHA synthesis. In experiment 1, rats were fed a standard diet containing either palm oil or rapeseed oil supplemented with pure anthocyanins for 8 weeks. Retrospective fatty acid analysis was conducted on plasma samples collected from a human randomized controlled trial where participants consumed an elderberry extract for 12 weeks (experiment 2). HepG2 cells were cultured with α-linolenic acid with or without select anthocyanins and their in vivo metabolites for 24 h and 48 h (experiment 3). The fatty acid composition of the cell membranes, plasma and liver tissues were analyzed by gas chromatography. Anthocyanins and anthocyanin-rich food intake had no significant impact on EPA or DHA status or FADS2 gene expression in any model system. These data indicate little impact of dietary anthocyanins on n-3 PUFA distribution and suggest that the increasingly recognized benefits of anthocyanins are unlikely to be the result of a beneficial impact on tissue fatty acid status. PMID:25573539

  3. Anthocyanins do not influence long-chain n-3 fatty acid status: studies in cells, rodents and humans.

    PubMed

    Vauzour, David; Tejera, Noemi; O'Neill, Colette; Booz, Valeria; Jude, Baptiste; Wolf, Insa M A; Rigby, Neil; Silvan, Jose Manuel; Curtis, Peter J; Cassidy, Aedin; de Pascual-Teresa, Sonia; Rimbach, Gerald; Minihane, Anne Marie

    2015-03-01

    Increased tissue status of the long-chain n-3 polyunsaturated fatty acids (LC n-3 PUFA), eicosapentaenoic (EPA) and docosahexaenoic acid (DHA) is associated with cardiovascular and cognitive benefits. Limited epidemiological and animal data suggest that flavonoids, and specifically anthocyanins, may increase EPA and DHA levels, potentially by increasing their synthesis from the shorter-chain n-3 PUFA, α-linolenic acid. Using complimentary cell, rodent and human studies we investigated the impact of anthocyanins and anthocyanin-rich foods/extracts on plasma and tissue EPA and DHA levels and on the expression of fatty acid desaturase 2 (FADS2), which represents the rate limiting enzymes in EPA and DHA synthesis. In experiment 1, rats were fed a standard diet containing either palm oil or rapeseed oil supplemented with pure anthocyanins for 8 weeks. Retrospective fatty acid analysis was conducted on plasma samples collected from a human randomized controlled trial where participants consumed an elderberry extract for 12 weeks (experiment 2). HepG2 cells were cultured with α-linolenic acid with or without select anthocyanins and their in vivo metabolites for 24 h and 48 h (experiment 3). The fatty acid composition of the cell membranes, plasma and liver tissues were analyzed by gas chromatography. Anthocyanins and anthocyanin-rich food intake had no significant impact on EPA or DHA status or FADS2 gene expression in any model system. These data indicate little impact of dietary anthocyanins on n-3 PUFA distribution and suggest that the increasingly recognized benefits of anthocyanins are unlikely to be the result of a beneficial impact on tissue fatty acid status.

  4. Racism and Surplus Repression.

    ERIC Educational Resources Information Center

    Johnson, Howard

    1983-01-01

    Explores the relationship between Herbert Marcuse's theory of "surplus repression" and Freud's theory of the "unconscious" with respect to latent, hidden, covert, or subliminal aspects of racism in the United States. Argues that unconscious racism, manifested in evasion/avoidance, acting out/projection, and attempted justification, perpetuates…

  5. Signaling from the embryo conditions Vp1-mediated repression of alpha-amylase genes in the aleurone of developing maize seeds.

    PubMed

    Hoecker, U; Vasil, I K; McCarty, D R

    1999-08-01

    The VP1 transcription factor functions as both a repressor and an activator of gene expression in the developing aleurone. Vp1 activation of the anthocyanin pathway exhibits strict cell autonomy in aleurone. In contrast, Vp1-mediated repression of hydrolase genes in aleurone cells during seed development is determined by a combination of cell autonomous and cell non-autonomous signals. To analyze signaling between the embryo and aleurone during seed development, a T-B3La chromosome translocation was used to create seed that has non-concordant embryo and endosperm genotypes. We show that de-repression of an Amy-GUS reporter gene in developing vp1 mutant aleurone cells strongly depends on the presence of a viviparous embryo. Genetic ablation of the developing embryo in vp1 mutant and Vp1 seeds through the introduction of an early embryo mutation caused a similar enhancement of Amy-GUS expression in the aleurone, suggesting that the quiescent embryo present in normal seed is a critical source of inhibitory signals. Analysis of an ABA deficient vp1 vp5 double mutant indicates that ABA synthesized in the embyro interacts additively with Vp1 to prevent precocious induction of alpha-amylase genes in the aleurone of the developing seed. A lack of ABA synthesis, however, does not account for the strongly synergistic interaction between a viviparous vp1 embryo and mutant aleurone suggesting that a quiescent embyro is a source of other inhibitory signals.

  6. Synthesis of oxadiazole-morpholine derivatives and manifestation of the repressed CD31 Microvessel Density (MVD) as tumoral angiogenic parameters in Dalton's Lymphoma.

    PubMed

    Al-Ghorbani, Mohammed; Vigneshwaran, V; Ranganatha, V Lakshmi; Prabhakar, B T; Khanum, Shaukath Ara

    2015-06-01

    A series of oxadiazole derivatives possessing morpholine 6a-l were synthesized by nucleophilic substitution reaction of key intermediates [1,3,4]-oxadiazole-2-thiol derivatives 5a-l with 4-(2-chloroethyl) morpholine. Compounds 6a-l were evaluated for their in vitro and in vivo antitumor potential in Dalton's Lymphoma Ascites (DLA) tumor cells. Among 6a-l series, compound 6a with concentration ∼8.5μM have shown extensive cytotoxicity in vitro and 85% reduction in tumor volume in vivo, attributing an excellent anti-proliferative capability towards the cancer cells. Compound 6a has extensively inhibited the Microvessel Density (MVD) or tumoral neovasculature which was evident from the CD31 immuno staining and peritoneal H&E staining. The major reason for the antiproliferative activity of compound 6a was due to the repression of tumor vasculature. PMID:26005956

  7. Jasmonic acid enhancement of anthocyanin accumulation is dependent on phytochrome A signaling pathway under far-red light in Arabidopsis.

    PubMed

    Li, Ting; Jia, Kun-Peng; Lian, Hong-Li; Yang, Xu; Li, Ling; Yang, Hong-Quan

    2014-11-01

    Anthocyanins are critical for plants. It is shown that the expression of genes encoding the key enzymes such as dihydroflavonol 4-reductase (DFR), UDP-Glc: flavonoid 3-O-glucosyltransferase (UF3GT), and leucoanthocyanidin dioxygenase (LDOX) in anthocyanin biosynthesis pathway is regulated by MYB75, a R2R3 MYB transcription factor. The production of anthocyanin is known to be promoted by jasmonic acid (JA) in light but not in darkness. The photoreceptors cryptochrome 1 (CRY1), phytochrome B (phyB), and phytochrome A (phyA) are also shown to mediate light promotion of anthocyanin accumulation, respectively, whereas their downstream factor COP1, a master negative regulator of photomorphogensis, represses anthocyanin accumulation. However, whether JA coordinates with photoreceptors in the regulation of anthocyanin accumulation is unknown. Here, we show that under far-red light, JA promotes anthocyanin accumulation in a phyA signaling pathway-dependent manner. The phyA mutant is hyposensitive to jasmonic acid analog methyl jasmonic acid (MeJA) under far-red light. The dominant mutant of MYB75, pap1-D, accumulates significantly higher levels of anthocyanin than wild type under far-red light, whereas knockdown of MYBs (MYB75, MYB90, MYB113, and MYB114) through RNAi significantly reduces MeJA promotion of anthocyanin accumulation. The phyA pap1-D double mutant shows reduced responsiveness to MeJA, similar to phyA mutant under far-red light. In darkness, a mutant allele of cop1, cop1-4, shows enhanced responsiveness to MeJA, but pap1-D mutant is barely responsive to MeJA. Upon MeJA application, the cop1-4 pap1-D double mutant accumulates considerably higher levels of anthocyanin than cop1-4 in darkness. Protein studies indicate that MYB75 protein is stabilized by white light and far-red light. Further gene expression studies suggest that MeJA promotes the expression of DFR, UF3GT, and LDOX genes in a phyA- and MYB75-dependent manner under far-red light. Our findings suggest

  8. Anthocyanin bioavailability: Past progress and current challenges

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Anthocyanins are the red, blue, and purple pigments present throughout nature. Foods rich in anthocyanins include berries, red cabbage, radish, eggplant, blue corn, and purple carrots, as well as many other red, purple, and blue fruits, vegetables, and legumes. Evidence continues to accumulate sugg...

  9. Potential mechanisms of cancer chemoprevention by anthocyanins.

    PubMed

    Hou, De-Xing

    2003-03-01

    Anthocyanins are the chemical components that give the intense color to many fruits and vegetables, such as blueberries, red cabbages and purple sweet potatoes. Epidemiological investigations have indicated that the moderate consumption of anthocyanin products such as red wine or bilberry extract is associated with a lower risk of cardiovascular disease and improvement of visual functions. Recently, there is increasing interesting in the pharmaceutical function of anthocyanins. This review summarizes current knowledge on the various molecular evidences of cancer chemoprevention by anthocyanins. These mechanisms can be subdivided into the following aspects: 1) the antioxidation; 2) the molecular mechanisms involved in anticarcinogenesis; 3) the molecular mechanisms involved in the apoptosis induction of tumor cells. Finally, the bioavailability and structure-activity relationship of anthocyanins are also summarized. PMID:12630561

  10. Potential mechanisms of cancer chemoprevention by anthocyanins.

    PubMed

    Hou, De-Xing

    2003-03-01

    Anthocyanins are the chemical components that give the intense color to many fruits and vegetables, such as blueberries, red cabbages and purple sweet potatoes. Epidemiological investigations have indicated that the moderate consumption of anthocyanin products such as red wine or bilberry extract is associated with a lower risk of cardiovascular disease and improvement of visual functions. Recently, there is increasing interesting in the pharmaceutical function of anthocyanins. This review summarizes current knowledge on the various molecular evidences of cancer chemoprevention by anthocyanins. These mechanisms can be subdivided into the following aspects: 1) the antioxidation; 2) the molecular mechanisms involved in anticarcinogenesis; 3) the molecular mechanisms involved in the apoptosis induction of tumor cells. Finally, the bioavailability and structure-activity relationship of anthocyanins are also summarized.

  11. Chemical PARP Inhibition Enhances Growth of Arabidopsis and Reduces Anthocyanin Accumulation and the Activation of Stress Protective Mechanisms

    PubMed Central

    Schulz, Philipp; Neukermans, Jenny; Van Der Kelen, Katrien; Mühlenbock, Per; Van Breusegem, Frank; Noctor, Graham; Teige, Markus; Metzlaff, Michael; Hannah, Matthew A.

    2012-01-01

    Poly-ADP-ribose polymerase (PARP) post-translationally modifies proteins through the addition of ADP-ribose polymers, yet its role in modulating plant development and stress responses is only poorly understood. The experiments presented here address some of the gaps in our understanding of its role in stress tolerance and thereby provide new insights into tolerance mechanisms and growth. Using a combination of chemical and genetic approaches, this study characterized phenotypes associated with PARP inhibition at the physiological level. Molecular analyses including gene expression analysis, measurement of primary metabolites and redox metabolites were used to understand the underlying processes. The analysis revealed that PARP inhibition represses anthocyanin and ascorbate accumulation under stress conditions. The reduction in defense is correlated with enhanced biomass production. Even in unstressed conditions protective genes and molecules are repressed by PARP inhibition. The reduced anthocyanin production was shown to be based on the repression of transcription of key regulatory and biosynthesis genes. PARP is a key factor for understanding growth and stress responses of plants. PARP inhibition allows plants to reduce protection such as anthocyanin, ascorbate or Non-Photochemical-Quenching whilst maintaining high energy levels likely enabling the observed enhancement of biomass production under stress, opening interesting perspectives for increasing crop productivity. PMID:22662141

  12. Glucocorticoid Repression of Inflammatory Gene Expression Shows Differential Responsiveness by Transactivation- and Transrepression-Dependent Mechanisms

    PubMed Central

    King, Elizabeth M.; Chivers, Joanna E.; Rider, Christopher F.; Minnich, Anne; Giembycz, Mark A.; Newton, Robert

    2013-01-01

    Binding of glucocorticoid to the glucocorticoid receptor (GR/NR3C1) may repress inflammatory gene transcription via direct, protein synthesis-independent processes (transrepression), or by activating transcription (transactivation) of multiple anti-inflammatory/repressive factors. Using human pulmonary A549 cells, we showed that 34 out of 39 IL-1β-inducible mRNAs were repressed to varying degrees by the synthetic glucocorticoid, dexamethasone. Whilst these repressive effects were GR-dependent, they did not correlate with either the magnitude of IL-1β-inducibility or the NF-κB-dependence of the inflammatory genes. This suggests that induction by IL-1β and repression by dexamethasone are independent events. Roles for transactivation were investigated using the protein synthesis inhibitor, cycloheximide. However, cycloheximide reduced the IL-1β-dependent expression of 13 mRNAs, which, along with the 5 not showing repression by dexamethasone, were not analysed further. Of the remaining 21 inflammatory mRNAs, cycloheximide significantly attenuated the dexamethasone-dependent repression of 11 mRNAs that also showed a marked time-dependence to their repression. Such effects are consistent with repression occurring via the de novo synthesis of a new product, or products, which subsequently cause repression (i.e., repression via a transactivation mechanism). Conversely, 10 mRNAs showed completely cycloheximide-independent, and time-independent, repression by dexamethasone. This is consistent with direct GR transrepression. Importantly, the inflammatory mRNAs showing attenuated repression by dexamethasone in the presence of cycloheximide also showed a significantly greater extent of repression and a higher potency to dexamethasone compared to those mRNAs showing cycloheximide-independent repression. This suggests that the repression of inflammatory mRNAs by GR transactivation-dependent mechanisms accounts for the greatest levels of repression and the most potent

  13. VIGS approach reveals the modulation of anthocyanin biosynthetic genes by CaMYB in chili pepper leaves

    PubMed Central

    Zhang, Zhen; Li, Da-Wei; Jin, Jing-Hao; Yin, Yan-Xu; Zhang, Huai-Xia; Chai, Wei-Guo; Gong, Zhen-Hui

    2015-01-01

    The purple coloration of pepper leaves arises from the accumulation of anthocyanin. Three regulatory and 12 structural genes have been characterized for their involvement in the anthocyanin biosynthesis. Examination of the abundance of these genes in leaves showed that the majority of them differed between anthocyanin pigmented line Z1 and non-pigmented line A3. Silencing of the R2R3-MYB transcription factor CaMYB in pepper leaves of Z1 resulted in the loss of anthocyanin accumulation. Moreover, the expression of multiple genes was altered in the silenced leaves. The expression of MYC was significantly lower in CaMYB-silenced leaves, whereas WD40 showed the opposite pattern. Most structural genes including CHS, CHI, F3H, F3′5′H, DFR, ANS, UFGT, ANP, and GST were repressed in CaMYB-silenced foliage with the exception of PAL, C4H, and 4CL. These results indicated that MYB plays an important role in the regulation of anthocyanin biosynthetic related genes. Besides CaMYB silenced leaves rendered more sporulation of Phytophthora capsici Leonian indicating that CaMYB might be involved in the defense response to pathogens. PMID:26217354

  14. VIGS approach reveals the modulation of anthocyanin biosynthetic genes by CaMYB in chili pepper leaves.

    PubMed

    Zhang, Zhen; Li, Da-Wei; Jin, Jing-Hao; Yin, Yan-Xu; Zhang, Huai-Xia; Chai, Wei-Guo; Gong, Zhen-Hui

    2015-01-01

    The purple coloration of pepper leaves arises from the accumulation of anthocyanin. Three regulatory and 12 structural genes have been characterized for their involvement in the anthocyanin biosynthesis. Examination of the abundance of these genes in leaves showed that the majority of them differed between anthocyanin pigmented line Z1 and non-pigmented line A3. Silencing of the R2R3-MYB transcription factor CaMYB in pepper leaves of Z1 resulted in the loss of anthocyanin accumulation. Moreover, the expression of multiple genes was altered in the silenced leaves. The expression of MYC was significantly lower in CaMYB-silenced leaves, whereas WD40 showed the opposite pattern. Most structural genes including CHS, CHI, F3H, F3'5'H, DFR, ANS, UFGT, ANP, and GST were repressed in CaMYB-silenced foliage with the exception of PAL, C4H, and 4CL. These results indicated that MYB plays an important role in the regulation of anthocyanin biosynthetic related genes. Besides CaMYB silenced leaves rendered more sporulation of Phytophthora capsici Leonian indicating that CaMYB might be involved in the defense response to pathogens. PMID:26217354

  15. Estimating contribution of anthocyanin pigments to osmotic adjustment during winter leaf reddening.

    PubMed

    Hughes, Nicole M; Carpenter, Kaylyn L; Cannon, Jonathan G

    2013-01-15

    The association between plant water stress and synthesis of red, anthocyanin pigments in leaves has led some plant biologists to propose an osmotic function of leaf reddening. According to this hypothesis, anthocyanins function as a solute in osmotic adjustment (OA), contributing to depression of osmotic potential (Ψ(π)) and maintenance of turgor pressure during drought-stressed conditions. Here we calculate the percent contribution of anthocyanin to leaf Ψ(π) during OA in two angiosperm evergreen species, Galax urceolata and Gaultheria procumbens. Both species exhibit dramatic leaf reddening under high light during winter, concomitant with declines in leaf water potential and accumulation of solutes. Data previously published by the authors on osmotic potential at full turgor (Ψ(π,100)) of G. urceolata and G. procumbens leaves before and after leaf reddening were used to estimate OA. In vivo molar concentrations of anthocyanin, glucose, fructose, and sucrose measured from the same individuals were converted to pressure equivalents using the Ideal Gas Law, and percent contribution to OA was estimated. Estimated mean OA during winter was -0.7MPa for G. urceolata and -0.8MPa for G. procumbens. In vivo concentrations of anthocyanin (3-10mM) were estimated to account for ∼2% of OA during winter, and comprised <0.7% of Ψ(π,100) in both species. Glucose, fructose, and sucrose combined accounted for roughly 50 and 80% of OA for G. urceolata and G. procumbens, respectively, and comprised ∼20% of Ψ(π,100). We observed that a co-occurring, acyanic species (Vinca minor) achieved similar OA without synthesizing anthocyanin. We conclude that anthocyanins represent a measurable, albeit meager, component of OA in red-leafed evergreen species during winter. However, due to their low concentrations, metabolic costliness relative to other osmolytes, and striking red color (unnecessary for an osmotic function), it is unlikely that they are synthesized solely for an

  16. New Challenges for the Design of High Value Plant Products: Stabilization of Anthocyanins in Plant Vacuoles

    PubMed Central

    Passeri, Valentina; Koes, Ronald; Quattrocchio, Francesca M.

    2016-01-01

    In the last decade plant biotechnologists and breeders have made several attempt to improve the antioxidant content of plant-derived food. Most efforts concentrated on increasing the synthesis of antioxidants, in particular anthocyanins, by inducing the transcription of genes encoding the synthesizing enzymes. We present here an overview of economically interesting plant species, both food crops and ornamentals, in which anthocyanin content was improved by traditional breeding or transgenesis. Old genetic studies in petunia and more recent biochemical work in brunfelsia, have shown that after synthesis and compartmentalization in the vacuole, anthocyanins need to be stabilized to preserve the color of the plant tissue over time. The final yield of antioxidant molecules is the result of the balance between synthesis and degradation. Therefore the understanding of the mechanism that determine molecule stabilization in the vacuolar lumen is the next step that needs to be taken to further improve the anthocyanin content in food. In several species a phenomenon known as fading is responsible for the disappearance of pigmentation which in some case can be nearly complete. We discuss the present knowledge about the genetic and biochemical factors involved in pigment preservation/destabilization in plant cells. The improvement of our understanding of the fading process will supply new tools for both biotechnological approaches and marker-assisted breeding. PMID:26909096

  17. Characterization of an activation-tagged mutant uncovers a role of GLABRA2 in anthocyanin biosynthesis in Arabidopsis.

    PubMed

    Wang, Xiaoyu; Wang, Xianling; Hu, Qingnan; Dai, Xuemei; Tian, Hainan; Zheng, Kaijie; Wang, Xiaoping; Mao, Tonglin; Chen, Jin-Gui; Wang, Shucai

    2015-07-01

    In Arabidopsis, anthocyanin biosynthesis is controlled by a MYB-bHLH-WD40 (MBW) transcriptional activator complex. The MBW complex activates the transcription of late biosynthesis genes in the flavonoid pathway, leading to the production of anthocyanins. A similar MBW complex regulates epidermal cell fate by activating the transcription of GLABRA2 (GL2), a homeodomain transcription factor required for trichome formation in shoots and non-hair cell formation in roots. Here we provide experimental evidence to show that GL2 also plays a role in regulating anthocyanin biosynthesis in Arabidopsis. From an activation-tagged mutagenized population of Arabidopsis plants, we isolated a dominant, gain-of-function mutant with reduced anthocyanins. Molecular cloning revealed that this phenotype is caused by an elevated expression of GL2, thus the mutant was named gl2-1D. Consistent with the view that GL2 acts as a negative regulator of anthocyanin biosynthesis, gl2-1D seedlings accumulated less whereas gl2-3 seedlings accumulated more anthocyanins in response to sucrose. Gene expression analysis indicated that expression of late, but not early, biosynthesis genes in the flavonoid pathway was dramatically reduced in gl2-1D but elevated in gl2-3 mutants. Further analysis showed that expression of some MBW component genes involved in the regulation of late biosynthesis genes was reduced in gl2-1D but elevated in gl2-3 mutants, and chromatin immunoprecipitation results indicated that some MBW component genes are targets of GL2. We also showed that GL2 functions as a transcriptional repressor. Taken together, these results indicate that GL2 negatively regulates anthocyanin biosynthesis in Arabidopsis by directly repressing the expression of some MBW component genes. PMID:26017690

  18. Carbon monoxide releasing molecule-2 CORM-2 represses global protein synthesis by inhibition of eukaryotic elongation factor eEF2.

    PubMed

    Schwer, Christian Ingo; Stoll, Patrick; Rospert, Sabine; Fitzke, Edith; Schallner, Nils; Bürkle, Hartmut; Schmidt, Rene; Humar, Matjaz

    2013-02-01

    Carbon monoxide (CO) is an endogenous gaseous transmitter that exerts antiproliferative effects in many cell types, but effects of CO on the translational machinery are not described. We examined the effects of the carbon monoxide releasing molecule-2 (CORM-2) on critical steps in translational signaling and global protein synthesis in pancreatic stellate cells (PSCs), the most prominent collagen-producing cells in the pancreas, whose activation is associated with pancreatic fibrosis. PSCs were isolated from rat pancreatic tissue and incubated with CORM-2. CORM-2 prevented the decrease in the phosphorylation of eukaryotic elongation factor 2 (eEF2) caused by serum. By contrast, the activation dependent phosphorylation of initiation factor 4E-binding protein 1 (4E-BP1) was inhibited by CORM-2 treatment. The phosphorylation of eukaryotic initiation factor 2α (eIF2α) and eukaryotic initiation factor 4E (eIF4E) were not affected by CORM-2 treatment. In consequence, CORM-2 mediated eEF2 phosphorylation and inactivation of 4E-BP1 suppressed global protein synthesis. These observations were associated with inhibition of phosphatidylinositol 3-kinase-Akt-mammalian target of rapamycin (PI3K-Akt-mTOR) signaling and increased intracellular calcium and cAMP levels. The CORM-2 mediated inhibition of protein synthesis resulted in downregulation of cyclin D1 and cyclin E expression, a subsequent decline in the phosphorylation of the retinoblastoma tumor suppressor protein (Rb) and cell growth arrest at the G(0)/G(1) phase checkpoint of the cell cycle. Our results suggest the therapeutic application of CO releasing molecules such as CORM-2 for the treatment of fibrosis, inflammation, cancer, or other pathologic states associated with excessive protein synthesis or hyperproliferation. However, prolonged exogenous application of CO might also have negative effects on cellular protein homeostasis.

  19. Light and the E3 ubiquitin ligase COP1/SPA control the protein stability of the MYB transcription factors PAP1 and PAP2 involved in anthocyanin accumulation in Arabidopsis.

    PubMed

    Maier, Alexander; Schrader, Andrea; Kokkelink, Leonie; Falke, Christian; Welter, Bastian; Iniesto, Elisa; Rubio, Vicente; Uhrig, Joachim F; Hülskamp, Martin; Hoecker, Ute

    2013-05-01

    Anthocyanins are natural pigments that accumulate only in light-grown and not in dark-grown Arabidopsis plants. Repression of anthocyanin accumulation in darkness requires the CONSTITUTIVELY PHOTOMORPHOGENIC1/SUPPRESSOR OF PHYA-105 (COP1/SPA) ubiquitin ligase, as cop1 and spa mutants produce anthocyanins also in the dark. Here, we show that COP1 and SPA proteins interact with the myeloblastosis (MYB) transcription factors PRODUCTION OF ANTHOCYANIN PIGMENT1 (PAP)1 and PAP2, two members of a small protein family that is required for anthocyanin accumulation and for the expression of structural genes in the anthocyanin biosynthesis pathway. The increased anthocyanin levels in cop1 mutants requires the PAP1 gene family, indicating that COP1 functions upstream of the PAP1 gene family. PAP1 and PAP2 proteins are degraded in the dark and this degradation is dependent on the proteasome and on COP1. Hence, the light requirement for anthocyanin biosynthesis results, at least in part, from the light-mediated stabilization of PAP1 and PAP2. Consistent with this conclusion, moderate overexpression of PAP1 leads to an increase in anthocyanin levels only in the light and not in darkness. Here we show that SPA genes are also required for reducing PAP1 and PAP2 transcript levels in dark-grown seedlings. Taken together, these results indicate that the COP1/SPA complex affects PAP1 and PAP2 both transcriptionally and post-translationally. Thus, our findings have identified mechanisms via which the COP1/SPA complex controls anthocyanin levels in Arabidopsis that may be useful for applications in biotechnology directed towards increasing anthocyanin content in plants.

  20. The Effect of Anthocyanins on Blood Pressure

    PubMed Central

    Zhu, Yongjian; Bo, Yacong; Wang, Xi; Lu, Wenjie; Wang, Xule; Han, Zhanying; Qiu, Chunguang

    2016-01-01

    Abstract The findings of clinical studies concerning the association between anthocyanins supplementation and blood pressure (BP) are inconsistent. In order to provide a more precise estimate of the overall effect of anthocyanins on systolic blood pressure (SBP) and diastolic blood pressure (DBP), we conducted a meta-analysis of clinical trials about anthocyanins supplementation and BP. PubMed, Web of Science, Wanfang Database, and China National Knowledge Infrastructure (CNKI) (until October 2015) were searched to identify potential studies with information on anthocyanins extract supplementation and arterial BP. The weighted mean difference (WMD) and 95% confidence interval (CI) were used as a summary statistic. Net changes in SBP and DBP between anthocyanins supplementation and placebo groups were calculated by subtracting the values at end of follow-up from those at baseline. Meta regression was used to explore the potential moderators of effect size. The publication bias was assessed using Begger's Funnel plots and Egger's tests; P < 0.05 was considered to be statistically significant. Finally, 6 clinical studies with 472 participants for the effect of anthocyanins consumption on BP were included in the present meta-analysis. There is no significant effect on either SBP (WMD: 1.15 mm Hg, 95% CI: −3.17 to 5.47, I2 = 56%) or DBP (WMD: 1.06 mm Hg, 95% CI: −0.71 to 2.83, I2 = 0%) following supplementation with anthocyanins. In summary, results from this meta-analysis do not favor any clinical efficacy of supplementation with anthocyanins in improving blood pressure. Further well-designed large randomized controlled trials (RCTs) with long follow-up period are needed to verify the association of anthocyanins supplementation and blood pressure. PMID:27082604

  1. AGEs decrease insulin synthesis in pancreatic β-cell by repressing Pdx-1 protein expression at the post-translational level.

    PubMed

    Shu, Tingting; Zhu, Yunxia; Wang, Hongdong; Lin, Yan; Ma, Zhuo; Han, Xiao

    2011-04-18

    Advanced glycation end products (AGEs) have been implicated in diverse pathological settings of many diabetic complications, and the possible mechanisms have been widely reported. However, the relationship between AGEs and pancreatic β-cell dysfunction is still poorly understood. Recent studies have shown that AGEs can impair β-cell function by inducing apoptosis or decreasing insulin secretion. Our previous research revealed that AGEs could significantly down-regulate insulin transcription and reduce β-cell glucose-stimulated insulin secretion (GSIS). Here, we investigated the possible mechanisms underlying AGE-related suppression of insulin synthesis. In the rat pancreatic β-cell line INS-1, we found that AGEs induced dephosphorylation of Foxo1 and increased its accumulation in the nucleus. The translocation of Foxo1 subsequently inhibited pancreatic-duodenal homeobox factor-1 (Pdx-1) levels in both nuclear and cytoplasmic compartments. We observed that with AGEs treatment, Pdx-1 protein levels decreased after 4 h, but there was no change in the Pdx-1 mRNA level or promoter activity at the same time point; this demonstrated that the decrease in Pdx-1 expression was not regulated at the transcriptional level. In our study, the decrease in Pdx-1 protein level was related to its reduced stability, overexpression of DN-Foxo1 could partially reverse the inhibition of Pdx-1 expression. Pretreatment with AGEs receptor (RAGE) antibody also prevented the AGE-induced diminution of Pdx-1 protein and insulin mRNA expression. In summary, AGEs induced nuclear accumulation of Foxo1; this in turn reduced Pdx-1 expression by decreasing its protein stability, ultimately affecting insulin synthesis.

  2. Recent Advances in Anthocyanin Analysis and Characterization

    PubMed Central

    Welch, Cara R.; Wu, Qingli; Simon, James E.

    2009-01-01

    Anthocyanins are a class of polyphenols responsible for the orange, red, purple and blue colors of many fruits, vegetables, grains, flowers and other plants. Consumption of anthocyanins has been linked as protective agents against many chronic diseases and possesses strong antioxidant properties leading to a variety of health benefits. In this review, we examine the advances in the chemical profiling of natural anthocyanins in plant and biological matrices using various chromatographic separations (HPLC and CE) coupled with different detection systems (UV, MS and NMR). An overview of anthocyanin chemistry, prevalence in plants, biosynthesis and metabolism, bioactivities and health properties, sample preparation and phytochemical investigations are discussed while the major focus examines the comparative advantages and disadvantages of each analytical technique. PMID:19946465

  3. Anthocyanin composition of wild bananas in Thailand.

    PubMed

    Kitdamrongsont, Kasipong; Pothavorn, Pongsagon; Swangpol, Sasivimon; Wongniam, Siripope; Atawongsa, Kanokporn; Svasti, Jisnuson; Somana, Jamorn

    2008-11-26

    Anthocyanins were isolated from male bracts of 10 wild species of bananas (Musa spp. and Ensete spp.) distributed in Thailand. Six major anthocyanin pigments were identified by high performance liquid chromatography (HPLC), mass spectrometry (MS), and tandem mass spectrometry (MS/MS). They are delphinidin-3-rutinoside (m/z 611.2), cyanidin-3-rutinoside (m/z 595.8), petunidin-3-rutinoside (m/z 624.9), pelargonidin-3-rutinoside (m/z 579.4), peonidin-3-rutinoside (m/z 608.7), and malvidin-3-rutinoside (m/z 638.8). On the basis of the types of pigment present, the wild bananas can be divided into 5 groups. The first group comprises M. itinerans, Musa sp. one, Musa sp. two, and M. acuminata accessions, which contain almost or all anthocyanin pigments except for pelargonidin-3-rutinoside, including both nonmethylated and methylated anthocyanins. The second group, M. acuminata subsp. truncata, contains only malvidin-3-rutinoside while the third group, M. coccinea, contains cyanidin-3-rutinoside and pelargonidin-3-rutinoside. The forth group, M. acuminata yellow bract and E. glaucum do not appear to contain any anthocyanin pigment. The fifth group consists of M. balbisiana, M. velutina, M. laterita, and E. superbum which contain only nonmethylated anthocyanin, delphinidin-3-rutinoside, and cyanidin-3-rutinoside. Total anthocyanin content in the analyzed bracts ranged from 0-119.70 mg/100 g bract fresh weight. The differences in the type of anthocyanin and variation in the amounts present indicate that wild bananas show biochemical diversity, which may be useful for identifying specific groups of bananas or for clarifying the evolution of flavonoid metabolism in each banana group.

  4. Comparative Leaves Transcriptome Analysis Emphasizing on Accumulation of Anthocyanins in Brassica: Molecular Regulation and Potential Interaction with Photosynthesis.

    PubMed

    Mushtaq, Muhammad A; Pan, Qi; Chen, Daozong; Zhang, Qinghua; Ge, Xianhong; Li, Zaiyun

    2016-01-01

    The purple leaf pigmentation mainly associated with anthocyanins accumulation is common in Brassica but the mechanisms of its production and its potential physiological functions are poorly understood. Here, we performed the phenotypic, cytological, physiological, and comparative leaves transcriptome analyses of 11 different varieties belonging to five Brassica species with purple or green leaves. We observed that the anthocyanin was accumulated in most of vegetative tissues in all species and also in reproduction organs of B. carinata. Anthocyanin accumulated in different part of purple leaves including adaxial and abaxial epidermal cells as well as palisade and spongy mesophyll cells. Leave transcriptome analysis showed that almost all late biosynthetic genes (LBGs) of anthocyanin, especially Dihydroflavonol 4-Reductase (DFR), Anthocyanidin Synthase (ANS) and Transparent Testa 19 (TT19), were highly up-regulated in all purple leaves. However, only one of transcript factors in anthocyanin biosynthesis pathway, Transparent Testa 8 (TT8), was up regulated along with those genes in all purple leaves, indicating its pivotal role for anthocyanin production in Brassica. Interestingly, with the up-regulation of genes for anthocyanin synthesis, Cytosolic 6-phosphogluconolactonase (PLG5) which involved in the oxidative pentose-phosphate pathway was up-regulated in all purple leaves and three genes FTSH PROTEASE 8 (FTS8), GLYCOLATE OXIDASE 1 (GOX1), and GLUTAMINE SYNTHETASE 1;4 (GLN1;4) related to degradation of photo-damaged proteins in photosystem II and light respiration were down-regulated. These results highlighted the potential physiological functions of anthocyanin accumulation related to photosynthesis which might be of great worth in future. PMID:27047501

  5. An Intracellular Laccase Is Responsible for Epicatechin-Mediated Anthocyanin Degradation in Litchi Fruit Pericarp1[OPEN

    PubMed Central

    Fang, Fang; Zhang, Xue-lian; Gong, Yi-hui; Li, Wen-jun; Shi, Zhao-wan; He, Quan; Wu, Qing; Li, Lu; Jiang, Lin-lin; Cai, Zhi-gao; Oren-Shamir, Michal; Zhang, Zhao-qi

    2015-01-01

    In contrast to the detailed molecular knowledge available on anthocyanin synthesis, little is known about its catabolism in plants. Litchi (Litchi chinensis) fruit lose their attractive red color soon after harvest. The mechanism leading to quick degradation of anthocyanins in the pericarp is not well understood. An anthocyanin degradation enzyme (ADE) was purified to homogeneity by sequential column chromatography, using partially purified anthocyanins from litchi pericarp as a substrate. The purified ADE, of 116 kD by urea SDS-PAGE, was identified as a laccase (ADE/LAC). The full-length complementary DNA encoding ADE/LAC was obtained, and a polyclonal antibody raised against a deduced peptide of the gene recognized the ADE protein. The anthocyanin degradation function of the gene was confirmed by its transient expression in tobacco (Nicotiana benthamiana) leaves. The highest ADE/LAC transcript abundance was in the pericarp in comparison with other tissues, and was about 1,000-fold higher than the polyphenol oxidase gene in the pericarp. Epicatechin was found to be the favorable substrate for the ADE/LAC. The dependence of anthocyanin degradation by the enzyme on the presence of epicatechin suggests an ADE/LAC epicatechin-coupled oxidation model. This model was supported by a dramatic decrease in epicatechin content in the pericarp parallel to anthocyanin degradation. Immunogold labeling transmission electron microscopy suggested that ADE/LAC is located mainly in the vacuole, with essential phenolic substances. ADE/LAC vacuolar localization, high expression levels in the pericarp, and high epicatechin-dependent anthocyanin degradation support its central role in pigment breakdown during pericarp browning. PMID:26514808

  6. Comparative Leaves Transcriptome Analysis Emphasizing on Accumulation of Anthocyanins in Brassica: Molecular Regulation and Potential Interaction with Photosynthesis.

    PubMed

    Mushtaq, Muhammad A; Pan, Qi; Chen, Daozong; Zhang, Qinghua; Ge, Xianhong; Li, Zaiyun

    2016-01-01

    The purple leaf pigmentation mainly associated with anthocyanins accumulation is common in Brassica but the mechanisms of its production and its potential physiological functions are poorly understood. Here, we performed the phenotypic, cytological, physiological, and comparative leaves transcriptome analyses of 11 different varieties belonging to five Brassica species with purple or green leaves. We observed that the anthocyanin was accumulated in most of vegetative tissues in all species and also in reproduction organs of B. carinata. Anthocyanin accumulated in different part of purple leaves including adaxial and abaxial epidermal cells as well as palisade and spongy mesophyll cells. Leave transcriptome analysis showed that almost all late biosynthetic genes (LBGs) of anthocyanin, especially Dihydroflavonol 4-Reductase (DFR), Anthocyanidin Synthase (ANS) and Transparent Testa 19 (TT19), were highly up-regulated in all purple leaves. However, only one of transcript factors in anthocyanin biosynthesis pathway, Transparent Testa 8 (TT8), was up regulated along with those genes in all purple leaves, indicating its pivotal role for anthocyanin production in Brassica. Interestingly, with the up-regulation of genes for anthocyanin synthesis, Cytosolic 6-phosphogluconolactonase (PLG5) which involved in the oxidative pentose-phosphate pathway was up-regulated in all purple leaves and three genes FTSH PROTEASE 8 (FTS8), GLYCOLATE OXIDASE 1 (GOX1), and GLUTAMINE SYNTHETASE 1;4 (GLN1;4) related to degradation of photo-damaged proteins in photosystem II and light respiration were down-regulated. These results highlighted the potential physiological functions of anthocyanin accumulation related to photosynthesis which might be of great worth in future.

  7. Comparative Leaves Transcriptome Analysis Emphasizing on Accumulation of Anthocyanins in Brassica: Molecular Regulation and Potential Interaction with Photosynthesis

    PubMed Central

    Mushtaq, Muhammad A.; Pan, Qi; Chen, Daozong; Zhang, Qinghua; Ge, Xianhong; Li, Zaiyun

    2016-01-01

    The purple leaf pigmentation mainly associated with anthocyanins accumulation is common in Brassica but the mechanisms of its production and its potential physiological functions are poorly understood. Here, we performed the phenotypic, cytological, physiological, and comparative leaves transcriptome analyses of 11 different varieties belonging to five Brassica species with purple or green leaves. We observed that the anthocyanin was accumulated in most of vegetative tissues in all species and also in reproduction organs of B. carinata. Anthocyanin accumulated in different part of purple leaves including adaxial and abaxial epidermal cells as well as palisade and spongy mesophyll cells. Leave transcriptome analysis showed that almost all late biosynthetic genes (LBGs) of anthocyanin, especially Dihydroflavonol 4-Reductase (DFR), Anthocyanidin Synthase (ANS) and Transparent Testa 19 (TT19), were highly up-regulated in all purple leaves. However, only one of transcript factors in anthocyanin biosynthesis pathway, Transparent Testa 8 (TT8), was up regulated along with those genes in all purple leaves, indicating its pivotal role for anthocyanin production in Brassica. Interestingly, with the up-regulation of genes for anthocyanin synthesis, Cytosolic 6-phosphogluconolactonase (PLG5) which involved in the oxidative pentose-phosphate pathway was up-regulated in all purple leaves and three genes FTSH PROTEASE 8 (FTS8), GLYCOLATE OXIDASE 1 (GOX1), and GLUTAMINE SYNTHETASE 1;4 (GLN1;4) related to degradation of photo-damaged proteins in photosystem II and light respiration were down-regulated. These results highlighted the potential physiological functions of anthocyanin accumulation related to photosynthesis which might be of great worth in future. PMID:27047501

  8. Anthocyanin accumulation and molecular analysis of anthocyanin biosynthesis-associated genes in eggplant (Solanum melongena L.).

    PubMed

    Zhang, Yanjie; Hu, Zongli; Chu, Guihua; Huang, Cheng; Tian, Shibing; Zhao, Zhiping; Chen, Guoping

    2014-04-01

    Eggplant (Solanum melongena L.) is an edible fruit vegetable cultivated and consumed worldwide. The purple eggplant is more eye-catching and popular for the health-promoting anthocyanins contained in the fruit skin. Two kinds of anthocyanin were separated and identified from purple cultivar (Zi Chang) by high-performance liquid chromatography-electrospray ionization tandem mass spectrometry. To investigate the molecular mechanisms of anthocyanin accumulation in eggplant, the transcripts of anthocyanin biosynthetic and regulatory genes were analyzed in the fruit skin and the flesh of the purple cultivar and the white cultivar (Bai Xue). Compared with the other tissues, SmMYB1 and all anthocyanin biosynthetic genes except PAL were dramatically upregulated in the fruit skin of the purple cultivar. Overexpression of SmMYB1 activated abundant anthocyanin accumulation in the regenerating shoots of eggplant. These results prove that transcriptional activation of SmMYB1 accounts for constitutive upregulation of most anthocyanin biosynthetic genes and the onset of anthocyanin biosynthesis in the purple cultivar.

  9. Novel insight into the mechanism underlying light-controlled anthocyanin accumulation in eggplant (Solanum melongena L.).

    PubMed

    Jiang, Mingmin; Ren, Li; Lian, Hongli; Liu, Yang; Chen, Huoying

    2016-08-01

    Eggplant is rich in anthocyanins, which are the major secondary metabolites and beneficial to human health. We discovered that the anthocyanin biosynthesis of eggplant cultivar 'Lanshan Hexian' was regulated by light. In this study, we isolated two blue light receptor genes, SmCRY1 and SmCRY2, and negative/positive anthocyanin regulatory factors SmCOP1 and SmHY5 from eggplant. In terms of transcript levels, SmCRY1, SmCRY2 and SmHY5 were up-regulated by light, while SmCOP1 was down-regulated. Subsequently, the four genes were functionally complemented in phenotype of corresponding mutants, indicating that they act as counterparts of Arabidopsis genes. Yeast two-hybrid and bimolecular fluorescence complementation assays showed that SmCRY1 and SmCRY2 interact with SmCOP1 in a blue-light-dependent manner. It also obtained the result that SmCOP1 interacts with SmHY5 and SmMYB1. Furthermore, using yeast one-hybrid assay, we found that SmHY5 and SmMYB1 both bind the promoters of anthocyanin biosynthesis structural genes (SmCHS and SmDFR). Taken together, blue-light-triggered CRY1/CRY2-COP1 interaction creates the condition that HY5 and MYB1 combine with the downstream anthocyanin synthesis genes (CHS and DFR) in eggplant. Our finding provides a new working model by which light controls anthocyanin accumulation in eggplant. PMID:27297989

  10. Nitrogen supply affects anthocyanin biosynthetic and regulatory genes in grapevine cv. Cabernet-Sauvignon berries.

    PubMed

    Soubeyrand, Eric; Basteau, Cyril; Hilbert, Ghislaine; van Leeuwen, Cornelis; Delrot, Serge; Gomès, Eric

    2014-07-01

    Accumulation of anthocyanins in grape berries is influenced by environmental factors (such as temperature and light) and supply of nutrients, i.e., fluxes of carbon and nitrogen feeding the berry cells. It is established that low nitrogen supply stimulates anthocyanin production in berry skin cells of red varieties. The present works aims to gain a better understanding of the molecular mechanisms involved in the response of anthocyanin accumulation to nitrogen supply in berries from field grown-plants. To this end, we developed an integrated approach combining monitoring of plant nitrogen status, metabolite measurements and transcript analysis. Grapevines (cv. Cabernet-Sauvignon) were cultivated in a vineyard with three nitrogen fertilization levels (0, 60 and 120 kg ha(-1) of nitrogen applied on the soil). Anthocyanin profiles were analyzed and compared with gene expression levels. Low nitrogen supply caused a significant increase in anthocyanin levels at two ripening stages (26 days post-véraison and maturity). Delphinidin and petunidin derivatives were the most affected compounds. Transcript levels of both structural and regulatory genes involved in anthocyanin synthesis confirmed the stimulation of the phenylpropanoid pathway. Genes encoding phenylalanine ammonia-lyase (PAL), chalcone synthase (CHS), flavonoid-3',5'-hydroxylase (F3'5'H), dihydroflavonol-4-reductase (DFR), leucoanthocyanidin dioxygenase (LDOX) exhibited higher transcript levels in berries from plant cultivated without nitrogen compared to the ones cultivated with 120 kg ha(-1) nitrogen fertilization. The results indicate that nitrogen controls a coordinated regulation of both positive (MYB transcription factors) and negative (LBD proteins) regulators of the flavonoid pathway in grapevine. PMID:24735825

  11. Novel insight into the mechanism underlying light-controlled anthocyanin accumulation in eggplant (Solanum melongena L.).

    PubMed

    Jiang, Mingmin; Ren, Li; Lian, Hongli; Liu, Yang; Chen, Huoying

    2016-08-01

    Eggplant is rich in anthocyanins, which are the major secondary metabolites and beneficial to human health. We discovered that the anthocyanin biosynthesis of eggplant cultivar 'Lanshan Hexian' was regulated by light. In this study, we isolated two blue light receptor genes, SmCRY1 and SmCRY2, and negative/positive anthocyanin regulatory factors SmCOP1 and SmHY5 from eggplant. In terms of transcript levels, SmCRY1, SmCRY2 and SmHY5 were up-regulated by light, while SmCOP1 was down-regulated. Subsequently, the four genes were functionally complemented in phenotype of corresponding mutants, indicating that they act as counterparts of Arabidopsis genes. Yeast two-hybrid and bimolecular fluorescence complementation assays showed that SmCRY1 and SmCRY2 interact with SmCOP1 in a blue-light-dependent manner. It also obtained the result that SmCOP1 interacts with SmHY5 and SmMYB1. Furthermore, using yeast one-hybrid assay, we found that SmHY5 and SmMYB1 both bind the promoters of anthocyanin biosynthesis structural genes (SmCHS and SmDFR). Taken together, blue-light-triggered CRY1/CRY2-COP1 interaction creates the condition that HY5 and MYB1 combine with the downstream anthocyanin synthesis genes (CHS and DFR) in eggplant. Our finding provides a new working model by which light controls anthocyanin accumulation in eggplant.

  12. Exogenous application of pectin-derived oligosaccharides to grape berries modifies anthocyanin accumulation, composition and gene expression.

    PubMed

    Villegas, Daniel; Handford, Michael; Alcalde, José Antonio; Perez-Donoso, Alonso

    2016-07-01

    Anthocyanins are secondary metabolites synthesized in grape berry skins via the phenylpropanoid pathway, with functions ranging from skin coloration to protection against pathogens or UV light. Accumulation of these compounds is highly variable depending on genetics, environmental factors and viticultural practices. Besides their biological functions, anthocyanins improve wine quality, as a high anthocyanin content in berries has a positive impact on the color, total phenolic concentration and, ultimately, the price of wine. The present work studies the effect of the pre-veraison application of pectin derived oligosaccharides (PDO) on the synthesis and accumulation of these compounds, and associates the changes observed with the expression of key genes in the phenylpropanoid pathways. To this end, pre-veraison Cabernet Sauvignon bunches were treated with PDO to subsequently determine total anthocyanin content, the anthocyanin profile (by HPLC-DAD) and gene expression (by qRT-PCR), using Ethrel and water treatments for comparison. The results show that PDO were as efficient as Ethrel in generating a significant rise in total anthocyanin content at 30 days after treatment (dat), compared with water treatments (1.32, 1.48 and 1.02 mg e.Mv-3G/g FW respectively) without any undesirable effect on berry size, soluble solids, tartaric acid concentration or pH. In addition, a significant alteration in the anthocyanin profile was observed. Specifically, a significant increase in the relative concentration of malvidin was observed for both PDO and Ethrel treatments, compared with water controls (52.8; 55.0 and 48.3%, respectively), with a significant rise in tri-hydroxylated forms and a fall in di-hydroxylated anthocyanins. The results of gene expression analyses suggest that the increment in total anthocyanin content is related to a short term increase in phenylalanine ammonia-lyase (PAL) expression, mediated by a decrease in MYB4A expression. A longer term increase in UDP

  13. Exogenous application of pectin-derived oligosaccharides to grape berries modifies anthocyanin accumulation, composition and gene expression.

    PubMed

    Villegas, Daniel; Handford, Michael; Alcalde, José Antonio; Perez-Donoso, Alonso

    2016-07-01

    Anthocyanins are secondary metabolites synthesized in grape berry skins via the phenylpropanoid pathway, with functions ranging from skin coloration to protection against pathogens or UV light. Accumulation of these compounds is highly variable depending on genetics, environmental factors and viticultural practices. Besides their biological functions, anthocyanins improve wine quality, as a high anthocyanin content in berries has a positive impact on the color, total phenolic concentration and, ultimately, the price of wine. The present work studies the effect of the pre-veraison application of pectin derived oligosaccharides (PDO) on the synthesis and accumulation of these compounds, and associates the changes observed with the expression of key genes in the phenylpropanoid pathways. To this end, pre-veraison Cabernet Sauvignon bunches were treated with PDO to subsequently determine total anthocyanin content, the anthocyanin profile (by HPLC-DAD) and gene expression (by qRT-PCR), using Ethrel and water treatments for comparison. The results show that PDO were as efficient as Ethrel in generating a significant rise in total anthocyanin content at 30 days after treatment (dat), compared with water treatments (1.32, 1.48 and 1.02 mg e.Mv-3G/g FW respectively) without any undesirable effect on berry size, soluble solids, tartaric acid concentration or pH. In addition, a significant alteration in the anthocyanin profile was observed. Specifically, a significant increase in the relative concentration of malvidin was observed for both PDO and Ethrel treatments, compared with water controls (52.8; 55.0 and 48.3%, respectively), with a significant rise in tri-hydroxylated forms and a fall in di-hydroxylated anthocyanins. The results of gene expression analyses suggest that the increment in total anthocyanin content is related to a short term increase in phenylalanine ammonia-lyase (PAL) expression, mediated by a decrease in MYB4A expression. A longer term increase in UDP

  14. Proteomics of red and white corolla limbs in petunia reveals a novel function of the anthocyanin regulator ANTHOCYANIN1 in determining flower longevity.

    PubMed

    Prinsi, Bhakti; Negri, Alfredo S; Quattrocchio, Francesca M; Koes, Ronald E; Espen, Luca

    2016-01-10

    The Petunia hybrida ANTHOCYANIN1 (AN1) gene encodes a transcription factor that regulates both the expression of genes involved in anthocyanin synthesis and the acidification of the vacuolar lumen in corolla epidermal cells. In this work, the comparison between the red flowers of the R27 line with the white flowers of the isogenic an1 mutant line W225 showed that the AN1 gene has further pleiotropic effects on flavonoid biosynthesis as well as on distant physiological traits. The proteomic profiling showed that the an1 mutation was associated to changes in accumulation of several proteins, affecting both anthocyanin synthesis and primary metabolism. The flavonoid composition study confirmed that the an1 mutation provoked a broad attenuation of the entire flavonoid pathway, probably by indirect biochemical events. Moreover, proteomic changes and variation of biochemical parameters revealed that the an1 mutation induced a delay in the onset of flower senescence in W225, as supported by the enhanced longevity of the W225 flowers in planta and the loss of sensitivity of cut flowers to sugar. This study suggests that AN1 is possibly involved in the perception and/or transduction of ethylene signal during flower senescence.

  15. Proteomics of red and white corolla limbs in petunia reveals a novel function of the anthocyanin regulator ANTHOCYANIN1 in determining flower longevity.

    PubMed

    Prinsi, Bhakti; Negri, Alfredo S; Quattrocchio, Francesca M; Koes, Ronald E; Espen, Luca

    2016-01-10

    The Petunia hybrida ANTHOCYANIN1 (AN1) gene encodes a transcription factor that regulates both the expression of genes involved in anthocyanin synthesis and the acidification of the vacuolar lumen in corolla epidermal cells. In this work, the comparison between the red flowers of the R27 line with the white flowers of the isogenic an1 mutant line W225 showed that the AN1 gene has further pleiotropic effects on flavonoid biosynthesis as well as on distant physiological traits. The proteomic profiling showed that the an1 mutation was associated to changes in accumulation of several proteins, affecting both anthocyanin synthesis and primary metabolism. The flavonoid composition study confirmed that the an1 mutation provoked a broad attenuation of the entire flavonoid pathway, probably by indirect biochemical events. Moreover, proteomic changes and variation of biochemical parameters revealed that the an1 mutation induced a delay in the onset of flower senescence in W225, as supported by the enhanced longevity of the W225 flowers in planta and the loss of sensitivity of cut flowers to sugar. This study suggests that AN1 is possibly involved in the perception and/or transduction of ethylene signal during flower senescence. PMID:26459403

  16. Stability-increasing effects of anthocyanin glycosyl acylation.

    PubMed

    Zhao, Chang-Ling; Yu, Yu-Qi; Chen, Zhong-Jian; Wen, Guo-Song; Wei, Fu-Gang; Zheng, Quan; Wang, Chong-De; Xiao, Xing-Lei

    2017-01-01

    This review comprehensively summarizes the existing knowledge regarding the chemical implications of anthocyanin glycosyl acylation, the effects of acylation on the stability of acylated anthocyanins and the corresponding mechanisms. Anthocyanin glycosyl acylation commonly refers to the phenomenon in which the hydroxyl groups of anthocyanin glycosyls are esterified by aliphatic or aromatic acids, which is synthetically represented by the acylation sites as well as the types and numbers of acyl groups. Generally, glycosyl acylation increases the in vitro and in vivo chemical stability of acylated anthocyanins, and the mechanisms primarily involve physicochemical, stereochemical, photochemical, biochemical or environmental aspects under specific conditions. Additionally, the acylation sites as well as the types and numbers of acyl groups influence the stability of acylated anthocyanins to different degrees. This review could provide insight into the optimization of the stability of anthocyanins as well as the application of suitable anthocyanins in food, pharmaceutical and cosmetic industries. PMID:27507456

  17. Phenylpropanoid metabolites and expression of key genes involved in anthocyanin biosynthesis in the shaded peel of apple fruit in response to sun exposure.

    PubMed

    Feng, Fengjuan; Li, Mingjun; Ma, Fengwang; Cheng, Lailiang

    2013-08-01

    The shaded peel of 'Fortune' (a red cultivar) and 'Mutsu' (a yellow/green cultivar) apple (Malus domestica Borkh.) was exposed to full sun by turning fruit 180° at about one week before harvest to determine the expression of key genes involved in anthocyanin synthesis in response to sunlight exposure and their relationships with the levels of anthocyanins and other phenolics. For the unturned (control) fruit, the shaded peel had lower expression levels of MdMYB10 (a transcriptional factor in the regulation of anthocyanin biosynthesis) and seven structural genes in anthocyanin synthesis (MdPAL, MdCHS, MdCHI, MdF3H, MdDFR1, MdLDOX, and MdUFGT), and lower levels of anthocyanins and flavonols than the sun-exposed peel in both cultivars. Exposure of the shaded peel to full sun caused marked up-regulation of the expression of MdMYB10 and all seven structural genes, which peaked between 6 h and 30 h after fruit turning, consequently leading to higher levels of anthocyanins, flavonols, and total phenolics than in the shaded peel and even in the sun-exposed peel of control fruit. Interestingly, the levels of flavonols were higher in the shaded peel of turned fruit (the original sun-exposed peel) than in the sun-exposed peel of both control and turned fruit in both cultivars, suggesting that competition for substrates exists in different branches of the phenylpropanoid pathway. These results indicate that sunlight exposure stimulates the expression of MdMYB10 and structural genes in anthocyanin synthesis, thereby elevating the levels of anthocyanins and other phenolic compounds in both red and yellow/green cultivars.

  18. Molecular genetics of blood-fleshed peach reveals activation of anthocyanin biosynthesis by NAC transcription factors.

    PubMed

    Zhou, Hui; Lin-Wang, Kui; Wang, Huiliang; Gu, Chao; Dare, Andrew P; Espley, Richard V; He, Huaping; Allan, Andrew C; Han, Yuepeng

    2015-04-01

    Anthocyanin pigmentation is an important consumer trait in peach (Prunus persica). In this study, the genetic basis of the blood-flesh trait was investigated using the cultivar Dahongpao, which shows high levels of cyanidin-3-glucoside in the mesocarp. Elevation of anthocyanin levels in the flesh was correlated with the expression of an R2R3 MYB transcription factor, PpMYB10.1. However, PpMYB10.1 did not co-segregate with the blood-flesh trait. The blood-flesh trait was mapped to a 200-kb interval on peach linkage group (LG) 5. Within this interval, a gene encoding a NAC domain transcription factor (TF) was found to be highly up-regulated in blood-fleshed peaches when compared with non-red-fleshed peaches. This NAC TF, designated blood (BL), acts as a heterodimer with PpNAC1 which shows high levels of expression in fruit at late developmental stages. We show that the heterodimer of BL and PpNAC1 can activate the transcription of PpMYB10.1, resulting in anthocyanin pigmentation in tobacco. Furthermore, silencing the BL gene reduces anthocyanin pigmentation in blood-fleshed peaches. The transactivation activity of the BL-PpNAC1 heterodimer is repressed by a SQUAMOSA promoter-binding protein-like TF, PpSPL1. Low levels of PpMYB10.1 expression in fruit at early developmental stages is probably attributable to lower levels of expression of PpNAC1 plus the presence of high levels of repressors such as PpSPL1. We present a mechanism whereby BL is the key gene for the blood-flesh trait in peach via its activation of PpMYB10.1 in maturing fruit. Partner TFs such as basic helix-loop-helix proteins and NAC1 are required, as is the removal of transcriptional repressors.

  19. Anthocyanin accumulation and transcriptional regulation of anthocyanin biosynthesis in purple bok choy (Brassica rapa var. chinensis).

    PubMed

    Zhang, Yanjie; Chen, Guoping; Dong, Tingting; Pan, Yu; Zhao, Zhiping; Tian, Shibing; Hu, Zongli

    2014-12-24

    Bok choy (Brassica rapa var. chinensis) is an important dietary vegetable cultivated and consumed worldwide for its edible leaves. The purple cultivars rich in health-promoting anthocyanins are usually more eye-catching and valuable. Fifteen kinds of anthocyanins were separated and identified from a purple bok choy cultivar (Zi He) by high-performance liquid chromatography-electrospray ionization tandem mass spectrometry. To investigate the molecular mechanisms underlying anthocyanin accumulation in bok choy, the expression profiles of anthocyanin biosynthetic and regulatory genes were analyzed in seedlings and leaves of the purple cultivar and the green cultivar (Su Zhouqing). Compared with the other tissues, BrTT8 and most of the anthocyanin biosynthetic genes were significantly up-regulated in the leaves and light-grown seedlings of Zi He. The results that heterologous expression of BrTT8 promotes the transcription of partial anthocyanin biosynthetic genes in regeneration shoots of tomato indicate that BrTT8 plays an important role in the regulation of anthocyanin biosynthesis.

  20. Anthocyanin accumulation and transcriptional regulation of anthocyanin biosynthesis in purple bok choy (Brassica rapa var. chinensis).

    PubMed

    Zhang, Yanjie; Chen, Guoping; Dong, Tingting; Pan, Yu; Zhao, Zhiping; Tian, Shibing; Hu, Zongli

    2014-12-24

    Bok choy (Brassica rapa var. chinensis) is an important dietary vegetable cultivated and consumed worldwide for its edible leaves. The purple cultivars rich in health-promoting anthocyanins are usually more eye-catching and valuable. Fifteen kinds of anthocyanins were separated and identified from a purple bok choy cultivar (Zi He) by high-performance liquid chromatography-electrospray ionization tandem mass spectrometry. To investigate the molecular mechanisms underlying anthocyanin accumulation in bok choy, the expression profiles of anthocyanin biosynthetic and regulatory genes were analyzed in seedlings and leaves of the purple cultivar and the green cultivar (Su Zhouqing). Compared with the other tissues, BrTT8 and most of the anthocyanin biosynthetic genes were significantly up-regulated in the leaves and light-grown seedlings of Zi He. The results that heterologous expression of BrTT8 promotes the transcription of partial anthocyanin biosynthetic genes in regeneration shoots of tomato indicate that BrTT8 plays an important role in the regulation of anthocyanin biosynthesis. PMID:25419600

  1. Maize anthocyanin regulatory gene pl is a duplicate of c1 that functions in the plant.

    PubMed

    Cone, K C; Cocciolone, S M; Burr, F A; Burr, B

    1993-12-01

    Genetic studies in maize have identified several regulatory genes that control the tissue-specific synthesis of purple anthocyanin pigments in the plant. c1 regulates pigmentation in the aleurone layer of the kernel, whereas pigmentation in the vegetative and floral tissues of the plant body depends on pl. c1 encodes a protein with the structural features of eukaryotic transcription factors and functions to control the accumulation of transcripts for the anthocyanin biosynthetic genes. Previous genetic and molecular observations have prompted the hypothesis that c1 and pl are functionally duplicate, in that they control the same set of anthocyanin structural genes but in distinct parts of the plant. Here, we show that this proposed functional similarity is reflected by DNA sequence homology between c1 and pl. Using a c1 DNA fragment as a hybridization probe, genomic and cDNA clones for pl were isolated. Comparison of pl and c1 cDNA sequences revealed that the genes encode proteins with 90% or more amino acid identity in the amino- and carboxyl-terminal domains that are known to be important for the regulatory function of the C1 protein. Consistent with the idea that the pl gene product also acts as a transcriptional activator is our finding that a functional pl allele is required for the transcription of at least three structural genes in the anthocyanin biosynthetic pathway. PMID:8305872

  2. Technique Selectively Represses Immune System

    MedlinePlus

    ... Research Matters December 3, 2012 Technique Selectively Represses Immune System Myelin (green) encases and protects nerve fibers (brown). A new technique prevents the immune system from attacking myelin in a mouse model of ...

  3. Contribution of Anthocyanin Composition to Total Antioxidant Capacity of Berries.

    PubMed

    Lee, Sang Gil; Vance, Terrence M; Nam, Tae-Gyu; Kim, Dae-Ok; Koo, Sung I; Chun, Ock K

    2015-12-01

    The present study aimed to evaluate the contribution of anthocyanin composition to the total antioxidant capacity (TAC) of berries having different anthocyanin composition; blackberry, black currant, and blueberry. Blackberry demonstrated the highest TAC, while it had the lowest total anthocyanin content among the three berries in both of the phenolic extract and anthocyanin fractions. On the other hand, black currant had the highest total anthocyanin content, but the lowest TAC. Cyanidin-3-O-glucoside (cya-3-glc) accounted for 94% of blackberry anthocyanins, and as one of the strongest antioxidants present in these three berries, it substantially contributed to the TAC of blackberry anthocyanin fraction (96.0%). Delphinidin-3-O-rutinoside and cyanidin-3-O-rutinoside in black currant had lower antioxidant capacities compared with delphinin-3-O-glucoside and cya-3-glc, resulting in its lowest TAC among berry anthocyanin fractions examined. Malvidin derivatives, major anthocyanins of blueberry, had considerably lower antioxidant capacity than other anthocyanidin derivatives, such as cyanidin or delphinidin, resulting in lower TAC of blueberry compared with blackberry. Our findings indicate that anthocyanin composition as well as the antioxidant capacity of individual anthocyanins contributes to the TAC of berries rich in distinct anthocyanins. PMID:26515081

  4. Expression and mapping of anthocyanin biosynthesis genes in carrot

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Anthocyanin gene expression has been extensively studied in leaves, fruits and flowers of numerous plants. Little, however, is known about anthocyanin accumulation in roots, or in carrots or other Apiaceae. We quantified expression of six anthocyanin biosynthetic genes (phenylalanine ammonia-lyase (...

  5. New member of the R2R3-MYB transcription factors family in grapevine suppresses the anthocyanin accumulation in the flowers of transgenic tobacco.

    PubMed

    Pérez-Díaz, J Ricardo; Pérez-Díaz, Jorge; Madrid-Espinoza, José; González-Villanueva, Enrique; Moreno, Yerko; Ruiz-Lara, Simón

    2016-01-01

    In grapevine, anthocyanins and proanthocyanidins are the main flavonoids in berries, which are associated to organoleptic properties in red wine such as color and astringency. Flavonoid pathway is specifically regulated at transcriptional level and several R2R3-MYB proteins have shown to act as positive regulators. However, some members of this family have shown to repress the flavonoid biosynthesis. In this work, we present the characterization of VvMYB4-like gene, which encodes a putative transcriptional factor highly expressed in the skin of berries at the pre veraison stage in grapevine. Its over-expression in tobacco resulted in the loss of pigmentation in flowers due a decrease in anthocyanin accumulation. Severity in anthocyanin suppression observed in petals could be associated with the expression level of the VvMYB4-like transgene. Expression analysis of flavonoid structural genes revealed the strong down-regulation of the flavonoid-related genes anthocyanidin synthase (ANS) and dihydroflavonol reductase (DFR) genes and also the reduction of the anthocyanin-related gene UDP glucose:flavonoid 3-O-glucosyl transferase (UFGT), which was dependent of the transgene expression. In addition, expression of VvMYB4-like in the model plant Arabidopsis showed similar results, with the higher down-regulation observed in the AtDFR and AtLDOX genes. These results suggest that VvMYB4-like may play an important role in regulation of anthocyanin biosynthesis in grapevine acting as a transcriptional repressor of flavonoid structural genes.

  6. Anthocyanins in the bracts of Curcuma species and relationship of the species based on anthocyanin composition.

    PubMed

    Koshioka, Masaji; Umegaki, Naoko; Boontiang, Kriangsuk; Pornchuti, Witayaporn; Thammasiri, Kanchit; Yamaguchi, Satoshi; Tatsuzawa, Fumi; Nakayama, Masayoshi; Tateishi, Akira; Kubota, Satoshi

    2015-03-01

    Five anthocyanins, delphinidin 3-O-rutinoside, cyanidin 3-O-rutinoside, petunidin 3-O-rutinoside, malvidin 3-O-glucoside and malvidin 3-O-rutinoside, were identified. Three anthocyanins, delphinidin 3-O-glucoside, cyanidin 3-O-glucoside and pelargonidin 3-O-rutinoside, were putatively identified based on C18 HPLC retention time, absorption spectrum, including λmax, and comparisons with those of corresponding standard anthocyanins, as the compounds responsible for the pink to purple-red pigmentation of the bracts of Curcuma alismatifolia and five related species. Cluster analysis based on four major anthocyanins formed two clusters. One consisted of only one species, C. alismatifolia, and the other consisted of five. Each cluster further formed sub-clusters depending on either species or habitats.

  7. Intermolecular binding of blueberry pectin-rich fractions and anthocyanin.

    PubMed

    Lin, Z; Fischer, J; Wicker, L

    2016-03-01

    Pectin was extracted from blueberry powder into three fractions of water soluble (WSF), chelator soluble (CSF) and sodium carbonate soluble (NSF). The fractions were incubated with cyanidin-3-glucoside (C3G), a mixture of five anthocyanidins (cyanidin, pelargonidin, malvidin, petunidin and delphinidin) or blueberry juice at pH 2.0-4.5. Free anthocyanins and bound anthocyanin-pectin mixtures were separated by ultrafiltration. WSF bound the least amount of anthocyanin at all pH values. CSF had stronger anthocyanin binding ability at pH 2.0-3.6, while NSF had stronger anthocyanin binding ability at pH 3.6-4.5. The pectin and anthocyanin binding was lowest at pH 4.5 and higher at pH 2.0-3.6. Nearly doubling C3G pigment content increased bound anthocyanin percentage by 16-23% at pH 3.6, which favored anthocyanin aromatic stacking, compared to 3-9% increase at pH 2.0. Ionic interaction between anthocyanin flavylium cations and free pectic carboxyl groups, and anthocyanin stacking may be two major mechanisms for pectin and anthocyanin binding. PMID:26471644

  8. Intermolecular binding of blueberry pectin-rich fractions and anthocyanin.

    PubMed

    Lin, Z; Fischer, J; Wicker, L

    2016-03-01

    Pectin was extracted from blueberry powder into three fractions of water soluble (WSF), chelator soluble (CSF) and sodium carbonate soluble (NSF). The fractions were incubated with cyanidin-3-glucoside (C3G), a mixture of five anthocyanidins (cyanidin, pelargonidin, malvidin, petunidin and delphinidin) or blueberry juice at pH 2.0-4.5. Free anthocyanins and bound anthocyanin-pectin mixtures were separated by ultrafiltration. WSF bound the least amount of anthocyanin at all pH values. CSF had stronger anthocyanin binding ability at pH 2.0-3.6, while NSF had stronger anthocyanin binding ability at pH 3.6-4.5. The pectin and anthocyanin binding was lowest at pH 4.5 and higher at pH 2.0-3.6. Nearly doubling C3G pigment content increased bound anthocyanin percentage by 16-23% at pH 3.6, which favored anthocyanin aromatic stacking, compared to 3-9% increase at pH 2.0. Ionic interaction between anthocyanin flavylium cations and free pectic carboxyl groups, and anthocyanin stacking may be two major mechanisms for pectin and anthocyanin binding.

  9. Nitrogen depletion and small R3-MYB transcription factors affecting anthocyanin accumulation in Arabidopsis leaves.

    PubMed

    Nemie-Feyissa, Dugassa; Olafsdottir, Solveig Margret; Heidari, Behzad; Lillo, Cathrine

    2014-02-01

    Ternary complexes consisting of a R2R3-MYB, a bHLH and a WD40 protein (MBW complexes) regulate trichome formation and anthocyanin synthesis in plants. Small R3-MYBs interact with the MBW complexes to exert a negative feedback, and thereby participate in regulation of epidermal cell fate, for example trichome numbers and clustering in leaves. In Arabidopsis thaliana, GL3, a bHLH transcription factor, is important in the MBW complex regulating trichome formation as well as in the MBW complex induced by nitrogen depletion and promoting anthocyanin formation. The small R3-MYBs: CPC, TRY, ETC1, ETC2, ETC3/CPL3, TCL1, MYBL2, are all known to interact with GL3. We here investigated these R3-MYBs in leaves of Arabidopsis rosette stage plants under nitrogen depletion to examine if the small MYBs would interfere with anthocyanin accumulation in plants under normal (autotrophic) growth conditions. CPC expression was enhanced two-fold in response to nitrogen depletion, and ETC3/CPL3 expression was enhanced by almost an order of magnitude (9×). Knockout of ETC3/CPL3 did not influence anthocyanin accumulation, but the results establish ETC3/CPL3 as a nitrate regulated gene and a putative candidate for being involved in nitrate status signaling and root development. Other R3-MYBs tested were not significantly influenced by nitrogen depletion. In conclusion, only CPC expression increased and clearly exerted a negative feedback on anthocyanin accumulation during nitrogen starvation in rosette leaves. PMID:24388610

  10. Comparison of Two Methods for Anthocyanin Quantification

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The pH differential method (AOAC method 2005.02) by spectrophotometer, and high performance liquid chromatography (HPLC) are methods commonly used by researchers and the food industry for quantifying anthocyanins of samples or products. This study was carried out to establish a relationship between ...

  11. Comparison of Two Methods for Anthocyanin Quantification

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The pH differential method (AOAC method 2005.02) by spectrophotometer and high performance liquid chromatography (HPLC) are methods commonly used by researchers and the food industry for quantifying anthocyanins of samples or products. This study was carried out to establish a relationship between t...

  12. Comparison of Two Methods for Anthocyanin Quantification

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The pH differential method (AOAC method 2005.02) by spectrophotometer, and high performance liquid chromatography (HPLC) are methods commonly used by researchers and the food industry for quantifying anthocyanins of samples or products. This study was carried out to establish a relationship between...

  13. Grape anthocyanin altered by absolute sunlight exclusion

    Technology Transfer Automated Retrieval System (TEKTRAN)

    This research was conducted to clarify anthocyanin accumulation within ‘Merlot’ grapes in response to microclimate, specifically to light incidence, temperature, and humidity. Treatment grape clusters were light-excluded during ripening by opaque white polypropylene enclosures, during which light in...

  14. Selective repression of light harvesting complex 2 formation in Rhodobacter azotoformans by light under semiaerobic conditions.

    PubMed

    Yue, Huiying; Zhao, Chungui; Li, Kai; Yang, Suping

    2015-11-01

    Photosystem formation in anaerobic anoxygenic phototrophic bacteria (APB) is repressed by oxygen but is de-repressed when oxygen tension decreases. Under semiaerobic conditions, the synthesis of photopigments and pigment protein complexes in Rhodobacter (Rba.) sphaeroides are repressed by light. AppA, a blue-light receptor, mediates this regulation. In the present study, it was showed that the synthesis of bacteriochlorophyll, carotenoid, and pigment protein complexes in Rba. azotoformans 134K20 was significantly repressed by oxygen. Oxygen exposure also led to a conversion of spheroidene to spheroidenone. In semiaerobically growing cells, light irradiation resulted in a decrease in the formation of photosystem, and blue light was found to be the most effective light source. Blue light reduced the contents of bacteriochlorophyll and carotenoid slightly, but had negligible effects on light harvesting complex (LH) 1 content, whereas the content of LH2 was significantly decreased indicating that blue light selectively repressed the synthesis of LH2 in semiaerobically growing 134K20. It was concluded that, similar to Rba. sphaeroides, a blue light receptor presented in strain 134K20 played important roles in its light-dependent repression. A possible mechanism involved in controlling the differential inhibitory of blue light on the synthesis of photosystem was discussed. PMID:26193456

  15. Glucose repression in Saccharomyces cerevisiae.

    PubMed

    Kayikci, Ömur; Nielsen, Jens

    2015-09-01

    Glucose is the primary source of energy for the budding yeast Saccharomyces cerevisiae. Although yeast cells can utilize a wide range of carbon sources, presence of glucose suppresses molecular activities involved in the use of alternate carbon sources as well as it represses respiration and gluconeogenesis. This dominant effect of glucose on yeast carbon metabolism is coordinated by several signaling and metabolic interactions that mainly regulate transcriptional activity but are also effective at post-transcriptional and post-translational levels. This review describes effects of glucose repression on yeast carbon metabolism with a focus on roles of the Snf3/Rgt2 glucose-sensing pathway and Snf1 signal transduction in establishment and relief of glucose repression.

  16. Glucose repression in Saccharomyces cerevisiae

    PubMed Central

    Kayikci, Ömur; Nielsen, Jens

    2015-01-01

    Glucose is the primary source of energy for the budding yeast Saccharomyces cerevisiae. Although yeast cells can utilize a wide range of carbon sources, presence of glucose suppresses molecular activities involved in the use of alternate carbon sources as well as it represses respiration and gluconeogenesis. This dominant effect of glucose on yeast carbon metabolism is coordinated by several signaling and metabolic interactions that mainly regulate transcriptional activity but are also effective at post-transcriptional and post-translational levels. This review describes effects of glucose repression on yeast carbon metabolism with a focus on roles of the Snf3/Rgt2 glucose-sensing pathway and Snf1 signal transduction in establishment and relief of glucose repression. PMID:26205245

  17. Coordinated regulation of biosynthetic and regulatory genes coincides with anthocyanin accumulation in developing eggplant fruit

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Violet to black pigmentation of eggplant (Solanum melongena) fruit is attributed to anthocyanin accumulation. Model systems support the interaction of biosynthetic and regulatory genes for anthocyanin biosynthesis. Anthocyanin structural gene transcription requires the expression of at least one m...

  18. Abiotic stresses induce different localizations of anthocyanins in Arabidopsis

    PubMed Central

    Kovinich, Nik; Kayanja, Gilbert; Chanoca, Alexandra; Otegui, Marisa S; Grotewold, Erich

    2015-01-01

    Anthocyanins are induced in plants in response to abiotic stresses such as drought, high salinity, excess light, and cold, where they often correlate with enhanced stress tolerance. Numerous roles have been proposed for anthocyanins induced during abiotic stresses including functioning as ROS scavengers, photoprotectants, and stress signals. We have recently found different profiles of anthocyanins in Arabidopsis (Arabidopsis thaliana) plants exposed to different abiotic stresses, suggesting that not all anthocyanins have the same function. Here, we discuss these findings in the context of other studies and show that anthocyanins induced in Arabidopsis in response to various abiotic stresses have different localizations at the organ and tissue levels. These studies provide a basis to clarify the role of particular anthocyanin species during abiotic stress. PMID:26179363

  19. Characterization and quantification of anthocyanins in red kiwifruit ( Actinidia spp.).

    PubMed

    Montefiori, Mirco; Comeskey, Daniel J; Wohlers, Mark; McGhie, Tony K

    2009-08-12

    Red-fleshed fruit occur in a small number of distantly related taxa in different sections of the genus Actinidia (kiwifruit). We describe and identify the anthocyanin profile of fruit of several Actinidia species. Differences in the relative amounts of cyanidin- and delphinidin-based anthocyanins determine whether the fruit appear red or purple. Cyanidin derivatives have been found in all Actinidia species that contain anthocyanins, whereas delphinidin derivatives are limited to two taxa: A. melanandra and A. arguta var. purpurea . The fruit of these not only contain a wider range of anthocyanins, but they also have greater concentrations. Anthocyanins of most Actinidia species are usually conjugated with either xylosyl-galactose or galactose, whereas A. deliciosa anthocyanins are conjugated with glucose and galactose.

  20. Synergistic repression of anaerobic genes by Mot3 and Rox1 in Saccharomyces cerevisiae

    PubMed Central

    Sertil, Odeniel; Kapoor, Rachna; Cohen, Brian D.; Abramova, Natalia; Lowry, Charles V.

    2003-01-01

    Two groups of anaerobic genes (genes induced in anaerobic cells and repressed in aerobic cells) are negatively regulated by heme, a metabolite present only in aerobic cells. Members of both groups, the hypoxic genes and the DAN/TIR/ERG genes, are jointly repressed under aerobic conditions by two factors. One is Rox1, an HMG protein, and the second, originally designated Rox7, is shown here to be Mot3, a global C2H2 zinc finger regulator. Repression of anaerobic genes results from co-induction of Mot3 and Rox1 in aerobic cells. Repressor synthesis is triggered by heme, which de-represses a mechanism controlling expression of both MOT3 and ROX1 in anaerobic cells; it includes Hap1, Tup1, Ssn6 and a fourth unidentified factor. The constitutive expression of various anaerobic genes in aerobic rox1Δ or mot3Δ cells directly implies that neither factor can repress by itself at endogenous levels and that stringent aerobic repression results from the concerted action of both. Mot3 and Rox1 are not essential components of a single complex, since each can repress independently in the absence of the other, when artificially induced at high levels. Moreover, the two repression mechanisms appear to be distinct: as shown here repression of ANB1 by Rox1 alone requires Tup1–Ssn6, whereas repression by Mot3 does not. Though artificially high levels of either factor can repress well, the absolute efficiency observed in normal cells when both are present—at much lower levels—demonstrates a novel inhibitory synergy. Evidently, expression levels for the two mutually dependent repressors are calibrated to permit a range of variation in basal aerobic expression at different promoters with differing operator site combinations. PMID:14530431

  1. New Anthocyanin-Human Salivary Protein Complexes.

    PubMed

    Ferrer-Gallego, Raúl; Soares, Susana; Mateus, Nuno; Rivas-Gonzalo, Julián; Escribano-Bailón, M Teresa; de Freitas, Victor

    2015-08-01

    The interaction between phenolic compounds and salivary proteins is considered the basis of the poorly understood phenomenon of astringency. Furthermore, this interaction is an important factor in relation to their bioavailability. In this work, interactions between anthocyanin and human salivary protein fraction were studied by mass spectrometry (MALDI-TOF-MS and FIA-ESI-MS) and saturation-transfer difference (STD) NMR spectroscopy. Anthocyanins were able to interact with saliva proteins. The dissociation constant (KD) between malvidin 3-glucoside and salivary proline-rich proteins was 1.92 mM for the hemiketal form (pH 3.4) and 1.83 mM for the flavylium cation (pH 1.0). New soluble complexes between these salivary proteins and malvidin 3-glucoside were identified for the first time.

  2. Salmonella promotes virulence by repressing cellulose production.

    PubMed

    Pontes, Mauricio H; Lee, Eun-Jin; Choi, Jeongjoon; Groisman, Eduardo A

    2015-04-21

    Cellulose is the most abundant organic polymer on Earth. In bacteria, cellulose confers protection against environmental insults and is a constituent of biofilms typically formed on abiotic surfaces. We report that, surprisingly, Salmonella enterica serovar Typhimurium makes cellulose when inside macrophages. We determine that preventing cellulose synthesis increases virulence, whereas stimulation of cellulose synthesis inside macrophages decreases virulence. An attenuated mutant lacking the mgtC gene exhibited increased cellulose levels due to increased expression of the cellulose synthase gene bcsA and of cyclic diguanylate, the allosteric activator of the BcsA protein. Inactivation of bcsA restored wild-type virulence to the Salmonella mgtC mutant, but not to other attenuated mutants displaying a wild-type phenotype regarding cellulose. Our findings indicate that a virulence determinant can promote pathogenicity by repressing a pathogen's antivirulence trait. Moreover, they suggest that controlling antivirulence traits increases long-term pathogen fitness by mediating a trade-off between acute virulence and transmission.

  3. Salmonella promotes virulence by repressing cellulose production

    PubMed Central

    Pontes, Mauricio H.; Lee, Eun-Jin; Choi, Jeongjoon; Groisman, Eduardo A.

    2015-01-01

    Cellulose is the most abundant organic polymer on Earth. In bacteria, cellulose confers protection against environmental insults and is a constituent of biofilms typically formed on abiotic surfaces. We report that, surprisingly, Salmonella enterica serovar Typhimurium makes cellulose when inside macrophages. We determine that preventing cellulose synthesis increases virulence, whereas stimulation of cellulose synthesis inside macrophages decreases virulence. An attenuated mutant lacking the mgtC gene exhibited increased cellulose levels due to increased expression of the cellulose synthase gene bcsA and of cyclic diguanylate, the allosteric activator of the BcsA protein. Inactivation of bcsA restored wild-type virulence to the Salmonella mgtC mutant, but not to other attenuated mutants displaying a wild-type phenotype regarding cellulose. Our findings indicate that a virulence determinant can promote pathogenicity by repressing a pathogen's antivirulence trait. Moreover, they suggest that controlling antivirulence traits increases long-term pathogen fitness by mediating a trade-off between acute virulence and transmission. PMID:25848006

  4. Salmonella promotes virulence by repressing cellulose production.

    PubMed

    Pontes, Mauricio H; Lee, Eun-Jin; Choi, Jeongjoon; Groisman, Eduardo A

    2015-04-21

    Cellulose is the most abundant organic polymer on Earth. In bacteria, cellulose confers protection against environmental insults and is a constituent of biofilms typically formed on abiotic surfaces. We report that, surprisingly, Salmonella enterica serovar Typhimurium makes cellulose when inside macrophages. We determine that preventing cellulose synthesis increases virulence, whereas stimulation of cellulose synthesis inside macrophages decreases virulence. An attenuated mutant lacking the mgtC gene exhibited increased cellulose levels due to increased expression of the cellulose synthase gene bcsA and of cyclic diguanylate, the allosteric activator of the BcsA protein. Inactivation of bcsA restored wild-type virulence to the Salmonella mgtC mutant, but not to other attenuated mutants displaying a wild-type phenotype regarding cellulose. Our findings indicate that a virulence determinant can promote pathogenicity by repressing a pathogen's antivirulence trait. Moreover, they suggest that controlling antivirulence traits increases long-term pathogen fitness by mediating a trade-off between acute virulence and transmission. PMID:25848006

  5. Molybdenum sequestration in Brassica species. A role for anthocyanins?

    PubMed

    Hale, K L; McGrath, S P; Lombi, E; Stack, S M; Terry, N; Pickering, I J; George, G N; Pilon-Smits, E A

    2001-08-01

    To elucidate plant mechanisms involved in molybdenum (Mo) sequestration and tolerance, Brassica spp. seedlings were supplied with molybdate, and the effects on plant physiology, morphology, and biochemistry were analyzed. When supplied with (colorless) molybdate Indian mustard (Brassica juncea) seedlings accumulated water-soluble blue crystals in their peripheral cell layers. Energy dispersive x-ray analysis showed that Mo accumulated predominantly in the vacuoles of the epidermal cells. Therefore, the blue crystals are likely to be a Mo compound. The x-ray absorption spectrum of the plant-accumulated Mo was different than that for molybdate, indicating complexation with a plant molecule. Because the blue compound was water soluble and showed a pH-dependent color change, possible involvement of anthocyanins was investigated. An anthocyanin-less mutant of Brassica rapa ("fast plants") was compared with varieties containing normal or high anthocyanin levels. The anthocyanin-less mutant did not show accumulation of a blue compound when supplied with molybdate. In the anthocyanin-containing varieties, the blue compound colocalized with anthocyanins in the peripheral cell layers. Mo accumulation by the three B. rapa varieties was positively correlated with anthocyanin content. Addition of molybdate to purified B. rapa anthocyanin resulted in an in vitro color change from pink to blue. Therefore, Mo appears to be sequestered in vacuoles of the peripheral cell layers of Brassica spp. as a blue compound, probably a Mo-anthocyanin complex.

  6. Molybdenum sequestration in Brassica species. A role for anthocyanins?

    PubMed

    Hale, K L; McGrath, S P; Lombi, E; Stack, S M; Terry, N; Pickering, I J; George, G N; Pilon-Smits, E A

    2001-08-01

    To elucidate plant mechanisms involved in molybdenum (Mo) sequestration and tolerance, Brassica spp. seedlings were supplied with molybdate, and the effects on plant physiology, morphology, and biochemistry were analyzed. When supplied with (colorless) molybdate Indian mustard (Brassica juncea) seedlings accumulated water-soluble blue crystals in their peripheral cell layers. Energy dispersive x-ray analysis showed that Mo accumulated predominantly in the vacuoles of the epidermal cells. Therefore, the blue crystals are likely to be a Mo compound. The x-ray absorption spectrum of the plant-accumulated Mo was different than that for molybdate, indicating complexation with a plant molecule. Because the blue compound was water soluble and showed a pH-dependent color change, possible involvement of anthocyanins was investigated. An anthocyanin-less mutant of Brassica rapa ("fast plants") was compared with varieties containing normal or high anthocyanin levels. The anthocyanin-less mutant did not show accumulation of a blue compound when supplied with molybdate. In the anthocyanin-containing varieties, the blue compound colocalized with anthocyanins in the peripheral cell layers. Mo accumulation by the three B. rapa varieties was positively correlated with anthocyanin content. Addition of molybdate to purified B. rapa anthocyanin resulted in an in vitro color change from pink to blue. Therefore, Mo appears to be sequestered in vacuoles of the peripheral cell layers of Brassica spp. as a blue compound, probably a Mo-anthocyanin complex. PMID:11500539

  7. Violent repression of environmental protests.

    PubMed

    Poulos, Helen M; Haddad, Mary Alice

    2016-01-01

    As global sea levels and natural resource demands rise, people around the world are increasingly protesting environmental threats to their lives and livelihoods. What are the conditions under which these peaceful environmental protests are violently repressed? This paper uses the random forest algorithm to conduct an event analysis of grassroots environmental protests around the world. Utilizing a database of 175 grassroots environmental protests, we found that: (1) a large proportion (37 %) of the protests involved violent repression; (2) most of the violence (56 %) was directed against marginalized groups; and (3) violence was geographically concentrated the global south in Latin America and Asia. The primary predictors of violence were political empowerment, GDP per capita, industry type, the presence of marginalized groups, and geographic region. Our analysis reveals a complex relationship between governance, resource extraction, and international funding that often resulted in human rights violations against marginalized groups. PMID:27026924

  8. Multiple R2R3-MYB Transcription Factors Involved in the Regulation of Anthocyanin Accumulation in Peach Flower

    PubMed Central

    Zhou, Hui; Peng, Qian; Zhao, Jianbo; Owiti, Albert; Ren, Fei; Liao, Liao; Wang, Lu; Deng, Xianbao; Jiang, Quan; Han, Yuepeng

    2016-01-01

    Anthocyanin accumulation is responsible for flower coloration in peach. Here, we report the identification and functional characterization of eight flavonoid-related R2R3-MYB transcription factors, designated PpMYB10.2, PpMYB9, PpMYBPA1, Peace, PpMYB17, PpMYB18, PpMYB19, and PpMYB20, respectively, in peach flower transcriptome. PpMYB10.2 and PpMYB9 are able to activate transcription of anthocyanin biosynthetic genes, whilst PpMYBPA1 and Peace have a strong activation on the promoters of proanthocyanin (PA) biosynthetic genes. PpMYB17-20 show a strong repressive effect on transcription of flavonoid pathway genes such as dihydroflavonol 4-reductase. These results indicate that anthocyanin accumulation in peach flower is coordinately regulated by a set of R2R3-MYB genes. In addition, PpMYB9 and PpMYB10.2 are closely related but separated into two groups, designated MYB9 and MYB10, respectively. PpMYB9 shows a strong activation on the PpUGT78A2 promoter, but with no effect on the promoter of PpUGT78B (commonly called PpUFGT in previous studies). In contrast, PpMYB10.2 is able to activate the PpUFGT promoter, but not for the PpUGT78A2 promoter. Unlike the MYB10 gene that is universally present in plants, the MYB9 gene is lost in most dicot species. Therefore, the PpMYB9 gene represents a novel group of anthocyanin-related MYB activators, which may have diverged in function from the MYB10 genes. Our study will aid in understanding the complex mechanism regulating floral pigmentation in peach and functional divergence of the R2R3-MYB gene family in plants.

  9. Repressive BMP2 gene regulatory elements near the BMP2 promoter

    SciTech Connect

    Jiang, Shan; Chandler, Ronald L.; Fritz, David T.; Mortlock, Douglas P.; Rogers, Melissa B.

    2010-02-05

    The level of bone morphogenetic protein 2 (BMP2) profoundly influences essential cell behaviors such as proliferation, differentiation, apoptosis, and migration. The spatial and temporal pattern of BMP2 synthesis, particular in diverse embryonic cells, is highly varied and dynamic. We have identified GC-rich sequences within the BMP2 promoter region that strongly repress gene expression. These elements block the activity of a highly conserved, osteoblast enhancer in response to FGF2 treatment. Both positive and negative gene regulatory elements control BMP2 synthesis. Detecting and mapping the repressive motifs is essential because they impede the identification of developmentally regulated enhancers necessary for normal BMP2 patterns and concentration.

  10. Mapping of an anthocyanin-regulating MYB transcription factor and its expression in red and green pear, Pyrus communis.

    PubMed

    Pierantoni, Luca; Dondini, Luca; De Franceschi, Paolo; Musacchi, Stefano; Winkel, Brenda S J; Sansavini, Silviero

    2010-12-01

    'Max Red Bartlett' is a red bud mutation of the yellow pear (Pyrus communis L.) cultivar 'Williams' (known as 'Bartlett' in North America). Anthocyanins are the most important pigments for red colour in fruits. Synthesis of anthocyanins is mediated by a number of well-characterized enzymes that include chalcone synthase (CHS), flavanone-3-hydroxylase (F3H), dihydroflavonol-4-reductase (DFR), anthocyanidin synthase (ANS), and UDP-glucose:flavonoid-3-O-glucosyltransferase (UFGT). Expression of the genes encoding these five enzymes was examined in pear fruit skin in order to elucidate the molecular mechanism for red coloration. In addition, the gene PcMYB10, encoding an R2R3 MYB transcription factor involved in anthocyanin biosynthetic pathway regulation, was isolated from both 'Williams' and 'Max Red Bartlett'. Analysis of the deduced amino acid sequence suggests that this gene is an ortholog of anthocyanin regulators known in other plant species. Its expression level was significantly higher in 'Max Red Bartlett' (red pear) compared with the original yellow variety 'Williams'. Although the map position of PcMYB10 corresponds to that of MdMYBa and MdMYB10, which control pigmentation of apple fruit skin, PcMYB10 is not directly responsible for red versus yellow colour in the two pear varieties, as the mutation underlying this difference maps to a different region of the pear genome.

  11. Anthocyanins from black soybean seed coat enhance wound healing.

    PubMed

    Xu, Lianji; Choi, Tae Hyun; Kim, Sukwha; Kim, Sang-Hyon; Chang, Hyuk Won; Choe, Misun; Kwon, Sun Young; Hur, Ji An; Shin, Sung Chul; Chung, Jong Il; Kang, Dawon; Zhang, Duo

    2013-10-01

    Anthocyanins are known to have antioxidant and antiinflammatory effects. We hypothesized that anthocyanins would enhance wound healing in Sprague-Dawley rats. The purpose of this study was to evaluate our hypothesis and investigate the mechanism of wound healing enhancement. The cytoprotective effect of an immortalized epidermal keratinocyte cell line (HaCaT) and human neonatal dermal fibroblasts in response to various concentrations of anthocyanins was determined. Vascular endothelial growth factor (VEGF) and thrombospondin 1 (TSP1) of HaCaT were measured by Western blot analysis. Anthocyanins were applied to the wounds in rats, and the healing ratio was calculated. Tissue VEGF, TSP1, CD31, nuclear factor-κB, and phosphorylation of IκBα were measured. The viability of the HaCaT cell line and human neonatal dermal fibroblasts increased under cytotoxicity by H2O2 in the anthocyanin-treated groups. The VEGF in the anthocyanin-treated groups increased, whereas TSP1 decreased. Wounds in the experimental groups healed faster, and VEGF and CD31 increased in the experimental groups, whereas TSP1 decreased. Anthocyanins inhibited the translocation of nuclear factor-κB (p65) from cytosol to nucleus and also prevented the phosphorylation of IκBα. Anthocyanins enhance wound healing through a cytoprotective effect, enhancement of angiogenesis, and an antiinflammatory effect.

  12. Anthocyanin regulatory/structural gene expression in Phalaenopsis

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Partial cDNA fragments of Myb, Myc, Wd, Chs and Dfr genes were generated by Reverse Transcription-PCR using total RNA isolated from flowers of P. amabilis (L.) Blume (anthocyanin-free) and P. schilleriana Rchb. f. (anthocyanin-containing) and cloned into a TOPO vector. RT-PCR revealed that the struc...

  13. Anthocyanins: Analysis and Distribution in Selected Medicinal Plants

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Anthocyanins are water soluble plant secondary metabolites responsible for the blue, purple, and red color of many plant tissues. They have been shown to be strong antioxidants, and may exert a wide range of health benefits through antioxidant or other mechanisms. Anthocyanins occur primarily as gly...

  14. Anthocyanins: analysis and distribution in selected medicinal plants

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Anthocyanins are water soluble plant secondary metabolites responsible for the blue, purple, and red color of many plant tissues. They have been shown to be strong antioxidants, and may exert a wide range of health benefits through antioxidant or other mechanisms. Anthocyanins occur primarily as g...

  15. Adsorption behavior of natural anthocyanin dye on mesoporous silica

    NASA Astrophysics Data System (ADS)

    Kohno, Yoshiumi; Haga, Eriko; Yoda, Keiko; Shibata, Masashi; Fukuhara, Choji; Tomita, Yasumasa; Maeda, Yasuhisa; Kobayashi, Kenkichiro

    2014-01-01

    Because of its non-toxicity, naturally occurring anthocyanin is potentially suitable as a colorant for foods and cosmetics. To the wider use of the anthocyanin, the immobilization on the inorganic host for an easy handling as well as the improvement of the stability is required. This study is focused on the adsorption of significant amount of the natural anthocyanin dye onto mesoporous silica, and on the stability enhancement of the anthocyanin by the complexation. The anthocyanin has successfully been adsorbed on the HMS type mesoporous silica containing small amount of aluminum. The amount of the adsorbed anthocyanin has been increased by modifying the pore wall with n-propyl group to make the silica surface hydrophobic. The light fastness of the adsorbed anthocyanin has been improved by making the composite with the HMS samples containing aluminum, although the degree of the improvement is not so large. It has been proposed that incorporation of the anthocyanin molecule deep inside the mesopore is required for the further enhancement of the stability.

  16. Contribution of anthocyanin fraction to the antioxidant properties of wine.

    PubMed

    Rivero-Pérez, M D; Muñiz, P; González-Sanjosé, M L

    2008-08-01

    The wine is a beverage with an important antioxidant efficiency which is attributed to their bioactives compounds, especially polyphenols. The anthocyanins are the main phenolic compounds of red wine and its consumption has been partially related with the "French Paradox". The aim of the present work was to evaluate the contribution of the anthocyanins to the antioxidant properties of red wines. So, total antioxidant capacity (TAC), hydroxyl and superoxide scavenger activity and lipid peroxidation of 80 Spanish red wines and their anthocyanins fractions have been assessed for ABTS, DPPH, DMPD, and FRAP methods, hydroxyl radical (HRSA), superoxide radical scavenger activity (SRSA) and ABAP-lipid peroxidation (ABAP-LP). The results showed that free anthocyanins fraction are main responsible of the total antioxidant capacity of red wines correlated with electron transference processes. In similar way, free anthocyanins are the maximum responsible of HRSA scavenger activity of red wines, contributing less extensively to their SRSA capacity or to their protective action on lipid peroxidation. Furthermore, simple anthocyanins exert a low action in TAC process involved with proton transference. Glycosilated and methoxylic anthocyanins as malvidin-3-glucoside, seem to be the type of anthocyanins with higher participation on the antioxidant effect of red wine.

  17. Biosynthesis and Metabolic Engineering of Anthocyanins in Arabidopsis thaliana

    PubMed Central

    Shi, Ming-Zhu; Xie, De-Yu

    2014-01-01

    Arabidopsis thaliana is the first model plant, the genome of which has been sequenced. In general, intensive studies on this model plant over the past nearly 30 years have led to many new revolutionary understandings in every single aspect of plant biology. Here, we review the current understanding of anthocyanin biosynthesis in this model plant. Although the investigation of anthocyanin structures in this model plant was not performed until 2002, numerous studies over the past three decades have been conducted to understand the biosynthesis of anthocyanins. To date, it appears that all pathway genes of anthocyanins have been molecularly, genetically and biochemically characterized in this plant. These fundamental accomplishments have made Arabidopsis an ideal model to understand the regulatory mechanisms of anthocyanin pathway. Several studies have revealed that the biosynthesis of anthocyanins is controlled by WD40-bHLH-MYB (WBM) transcription factor complexes under lighting conditions. However, how different regulatory complexes coordinately and specifically regulate the pathway genes of anthocyanins remains unclear. In this review, we discuss current progresses and findings including structural diversity, regulatory properties and metabolic engineering of anthocyanins in Arabidopsis thaliana. PMID:24354533

  18. Blueberry estimated harvest from seven new cultivars: fruit and anthocyanins.

    PubMed

    Scalzo, Jessica; Stevenson, David; Hedderley, Duncan

    2013-08-15

    This study compares the yields, weights and anthocyanin contents of fruit from a group of seven new cultivars released from the New Zealand blueberry breeding programme and selected for the longest possible combined harvest season. The measured factors were primarily influenced by cultivar, and seasonal variations had relatively minor effects. The late-ripening cultivars 'Velluto Blue' and 'Centra Blue' had the highest fruit yields, anthocyanin contents and estimated total anthocyanin harvestable from a given area. 'Blue Moon' and 'Sky Blue' had the largest fruit sizes. The early-ripening cultivars 'Blue Bayou', 'Blue Moon' and 'Sunset Blue' had the lowest anthocyanin contents. The yield, fruit size and total anthocyanin content results obtained from any single year were highly correlated with the average of the three years, which makes pursuing the evaluation for these traits from a single year and at an early stage of plant development a practical proposition. PMID:23561076

  19. Stability and bioaccessibility of anthocyanins in bakery products enriched with anthocyanins.

    PubMed

    Karakaya, Sibel; Simsek, Sebnem; Eker, Alper Tolga; Pineda-Vadillo, Carlos; Dupont, Didier; Perez, Beatriz; Viadel, Blanca; Sanz-Buenhombre, Marisa; Rodriguez, Alberto Guadarrama; Kertész, Zsófia; Hegyi, Adrienn; Bordoni, Alessandra; El, Sedef Nehir

    2016-08-10

    Anthocyanins, water soluble polyphenols, have been associated with several beneficial health effects. The aim of this study was to determine how the baking process and food matrix affect anthocyanin stability and bioaccessibility in bakery products in order to develop functional foods. Three well known regularly consumed bakery products (buns, breadsticks and biscuits) were enriched with anthocyanin (AC) isolated from grape skin alone or in combination with docosahexaenoic acid (AC + DHA) to reveal knowledge on AC as active ingredients in real food systems rather than pure compounds. Anthocyanin amounts added to the formulations of buns, breadsticks and biscuits were 34 mg per 100 g, 40 mg per 100 g and 37 mg per 100 g, respectively. The effect of processing, storage and the food matrix on AC stability and bioaccessibility was investigated. In addition, the sensory properties of bakery products were evaluated. Breadsticks enriched with AC and AC + DHA received the lowest scores in the pre-screening sensory test. Therefore breadsticks were excluded from further analysis. AC retentions, which were monitored by determination of malvidin 3-O-glucoside, in the bun and biscuit after baking were 95.9% (13.6 mg per 100 g) and 98.6% (15.2 mg per 100 g), respectively. Biscuits and buns enriched only with AC showed significantly higher anthocyanin bioaccessibilities (57.26% and 57.30%, respectively) than the same ones enriched with AC + DHA. AC stability in enriched products stored for 21 days was significantly lower than in products stored for 7 days (p < 0.05). However, this loss can be accepted as negligible since more than 70% of AC was retained in all the products.

  20. Stability and bioaccessibility of anthocyanins in bakery products enriched with anthocyanins.

    PubMed

    Karakaya, Sibel; Simsek, Sebnem; Eker, Alper Tolga; Pineda-Vadillo, Carlos; Dupont, Didier; Perez, Beatriz; Viadel, Blanca; Sanz-Buenhombre, Marisa; Rodriguez, Alberto Guadarrama; Kertész, Zsófia; Hegyi, Adrienn; Bordoni, Alessandra; El, Sedef Nehir

    2016-08-10

    Anthocyanins, water soluble polyphenols, have been associated with several beneficial health effects. The aim of this study was to determine how the baking process and food matrix affect anthocyanin stability and bioaccessibility in bakery products in order to develop functional foods. Three well known regularly consumed bakery products (buns, breadsticks and biscuits) were enriched with anthocyanin (AC) isolated from grape skin alone or in combination with docosahexaenoic acid (AC + DHA) to reveal knowledge on AC as active ingredients in real food systems rather than pure compounds. Anthocyanin amounts added to the formulations of buns, breadsticks and biscuits were 34 mg per 100 g, 40 mg per 100 g and 37 mg per 100 g, respectively. The effect of processing, storage and the food matrix on AC stability and bioaccessibility was investigated. In addition, the sensory properties of bakery products were evaluated. Breadsticks enriched with AC and AC + DHA received the lowest scores in the pre-screening sensory test. Therefore breadsticks were excluded from further analysis. AC retentions, which were monitored by determination of malvidin 3-O-glucoside, in the bun and biscuit after baking were 95.9% (13.6 mg per 100 g) and 98.6% (15.2 mg per 100 g), respectively. Biscuits and buns enriched only with AC showed significantly higher anthocyanin bioaccessibilities (57.26% and 57.30%, respectively) than the same ones enriched with AC + DHA. AC stability in enriched products stored for 21 days was significantly lower than in products stored for 7 days (p < 0.05). However, this loss can be accepted as negligible since more than 70% of AC was retained in all the products. PMID:27415853

  1. Corepressor system for catabolite repression of the lac operon in Escherichia coli.

    PubMed

    Dobrogosz, W J

    1969-03-01

    Acetylated amino sugars, normally used in the biosynthesis of cell walls and cell membranes, were found to play a role as corepressors for catabolite repression of the lac operon in Escherichia coli. This conclusion was derived from studies conducted on mutants of E. coli that were able to assimilate an exogenous source of N-acetylglucosamine (AcGN) but were unable to dissimilate or grow on this compound. At concentrations less than 10(-4)m, AcGN caused severe catabolite repression of beta-galactosidase synthesis in cultures grown under either nonrepressed or partially repressed conditions. This repression occurred in the absence of any effect of AcGN on either the carbon and energy metabolism or the growth of the organism. In addition, this repression by AcGN occurred in a mutant strain that is constitutive for beta-galactosidase production, demonstrating that the AcGN effect does not involve the uptake of inducer. This model for the corepressor system of catabolite repression is discussed in relation to the existing theories on repression of the lac operon. PMID:4887497

  2. Development of table and raisin grapes with high anthocyanins using a leaf disk assay.

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Anthocyanins are considered an excellent source of antioxidant phytochemicals for health benefits. The majority of wine, table and raisin grapes have anthocyanins only in their colored skin. Anthocyanin content of grapes would be increased if their flesh also contained anthocyanins. C33-30, a see...

  3. Development of Table and Raisin Grapes With High Anthocyanins Using a Leaf Disk Assay.

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Anthocyanins are considered an excellent source of antioxidant phytochemicals for health benefits. The majority of wine, table and raisin grapes have anthocyanins only in their colored skin. Anthocyanin content of grapes would be increased if their flesh also contained anthocyanins. Rubired wine ...

  4. [Catabolyte repression of Escherichia coli K12 mutants with defects in different systems of glucose transport].

    PubMed

    Gershanovich, V N; Iurovitskaia, N V; Komissarova, L V; Bol'shakova, T N; Erlagaeva, R S

    1976-01-01

    The phenomenon of glucose catabolite repression was studied in E. coli mutants inable to transport this carbohydrate. The pts 1, H mutant P34 was much less sensitive to the repressive effect of glucose on beta-galactosidase synthesis than the parent type. The 1103 mutant devoid of enzyme 1 of the phosphoenolpyruvate-dependent phosphotransferase system (PTS) behaves in the same way as P34 mutant after addition of glucose to casamino acid mineral medium. However, in minimal medium with succinate as the sole source of carbon, cells of the 1103 mutant show enhanced sensibility to transient glucose repression. The effect of hypersensibility disappears when the lac I mutation leading to constitutive the beta-galactosidase synthesis is introduced in 1103 mutant. It is shown that the enhanced sensibility of beta-galactosidase synthesis to glucose transient repression in 1103 mutant is an effect of the aburpt decrease in its growth rate in the presence of succinate and most probably this decrease leads to "inducer exclusion" of the lac operon. It is also shown that if one introduces the P34 mutation in strain JD3 devoid of one of the enzymes II for glucose (and due to this resistant to glucose catabolite respression) then the level of resistance in double mutant does not increase in spite of considerable supression of 14C glucose accumulation. In connection with this the role is discussed of separate components of the E. coli K 12 glucose transport system in realization of the phenomenon of catabolite repression. PMID:785237

  5. Gibberellins repress photomorphogenesis in darkness.

    PubMed

    Alabadí, David; Gil, Joan; Blázquez, Miguel A; García-Martínez, José L

    2004-03-01

    Plants undergo two different developmental programs depending on whether they are growing in darkness (skotomorphogenesis) or in the presence of light (photomorphogenesis). It has been proposed that the latter is the default pathway followed by many plants after germination and before the seedling emerges from soil. The transition between the two pathways is tightly regulated. The conserved COP1-based complex is central in the light-dependent repression of photomorphogenesis in darkness. Besides this control, hormones such as brassinosteroids (BRs), cytokinins, auxins, or ethylene also have been shown to regulate, to different extents, this developmental switch. In the present work, we show that the hormone gibberellin (GA) widely participates in this regulation. Studies from Arabidopsis show that both chemical and genetic reductions of endogenous GA levels partially derepress photomorphogenesis in darkness. This is based both on morphological phenotypes, such as hypocotyl elongation and hook and cotyledon opening, and on molecular phenotypes, such as misregulation of the light-controlled genes CAB2 and RbcS. Genetic studies indicate that the GA signaling elements GAI and RGA participate in these responses. Our results also suggest that GA regulation of this response partially depends on BRs. This regulation seems to be conserved across species because lowering endogenous GA levels in pea (Pisum sativum) induces full de-etiolation in darkness, which is not reverted by BR application. Our results, therefore, attribute an important role for GAs in the establishment of etiolated growth and in repression of photomorphogenesis. PMID:14963246

  6. Molecular cloning and characterization of three genes encoding dihydroflavonol-4-reductase from Ginkgo biloba in anthocyanin biosynthetic pathway.

    PubMed

    Hua, Cheng; Linling, Li; Shuiyuan, Cheng; Fuliang, Cao; Feng, Xu; Honghui, Yuan; Conghua, Wu

    2013-01-01

    Dihydroflavonol-4-reductase (DFR, EC1.1.1.219) catalyzes a key step late in the biosynthesis of anthocyanins, condensed tannins (proanthocyanidins), and other flavonoids important to plant survival and human nutrition. Three DFR cDNA clones (designated GbDFRs) were isolated from the gymnosperm Ginkgo biloba. The deduced GbDFR proteins showed high identities to other plant DFRs, which form three distinct DFR families. Southern blot analysis showed that the three GbDFRs each belong to a different DFR family. Phylogenetic tree analysis revealed that the GbDFRs share the same ancestor as other DFRs. The expression of the three recombinant GbDFRs in Escherichia coli showed that their actual protein sizes were in agreement with predictions from the cDNA sequences. The recombinant proteins were purified and their activity was analyzed; both GbDFR1 and GbDFR3 could catalyze dihydroquercetin conversion to leucocyanidin, while GbDFR2 catalyzed dihydrokaempferol conversion to leucopelargonidin. qRT-PCR showed that the GbDFRs were expressed in a tissue-specific manner, and transcript accumulation for the three genes was highest in young leaves and stamens. These transcription patterns were in good agreement with the pattern of anthocyanin accumulation in G.biloba. The expression profiles suggested that GbDFR1 and GbDFR2 are mainly involved in responses to plant hormones, environmental stress and damage. During the annual growth cycle, the GbDFRs were significantly correlated with anthocyanin accumulation in leaves. A fitted linear curve showed the best model for relating GbDFR2 and GbDFR3 with anthocyanin accumulation in leaves. GbDFR1 appears to be involved in environmental stress response, while GbDFR3 likely has primary functions in the synthesis of anthocyanins. These data revealed unexpected properties and differences in three DFR proteins from a single species. PMID:23991027

  7. Structure of the acyl-glucose-dependent anthocyanin 5-O-glucosyltransferase gene in carnations and its disruption by transposable elements in some varieties.

    PubMed

    Nishizaki, Yuzo; Matsuba, Yuki; Okamoto, Emi; Okamura, Masachika; Ozeki, Yoshihiro; Sasaki, Nobuhiro

    2011-12-01

    The pink, red and crimson petal colors of carnations (Dianthus caryophyllus) are produced by anthocyanins. The anthocyanins, pelargonidin and cyanidin can be modified by two glucoses at the 3 and 5 positions, and by a single malic acid. Petal color variation can result from failure of such modification, for example, the lack of a glucose at the 5 position is responsible for the color variants of some commercial varieties. With respect to this variation, modification by 5-O-glucosyltransferase plays the most important role in glucosylation at the 5 position. Recently, we identified a novel acyl-glucose-dependent anthocyanin 5-O-glucosyltransferase (AA5GT), that uses acyl-glucoses, but not UDP-glucose, as the glucose donor. Although we showed that loss of AA5GT expression was responsible for loss of glucosylation at the 5 position of anthocyanin in some varieties, the cause of this repression of AA5GT expression could not be determined. Here, we have succeeded in isolating the AA5GT gene and found that it consists of 12 exons and 11 introns. In carnation varieties lacking a glucose at the 5 position, we identified the insertion of two different retrotransposons, Ty1dic1 and Retdic1, into AA5GT. Ty1dic1, which belongs to the class I long terminal repeat (LTR)-retrotransposons of Ty1/copia families, was inserted into exon 10. Retdic1, which includes a long interspersed nuclear element (LINE)-like sequence, was inserted into intron 5. Thus, insertion of either Ty1dic1 or Retdic1 can disrupt AA5GT and result in the lack of glucosylation at the 5 position in anthocyanins.

  8. Transcriptome analysis of an apple (Malus × domestica) yellow fruit somatic mutation identifies a gene network module highly associated with anthocyanin and epigenetic regulation.

    PubMed

    El-Sharkawy, Islam; Liang, Dong; Xu, Kenong

    2015-12-01

    Using RNA-seq, this study analysed an apple (Malus×domestica) anthocyanin-deficient yellow-skin somatic mutant 'Blondee' (BLO) and its red-skin parent 'Kidd's D-8' (KID), the original name of 'Gala', to understand the molecular mechanisms underlying the mutation. A total of 3299 differentially expressed genes (DEGs) were identified between BLO and KID at four developmental stages and/or between two adjacent stages within BLO and/or KID. A weighted gene co-expression network analysis (WGCNA) of the DEGs uncovered a network module of 34 genes highly correlated (r=0.95, P=9.0×10(-13)) with anthocyanin contents. Although 12 of the 34 genes in the WGCNA module were characterized and known of roles in anthocyanin, the remainder 22 appear to be novel. Examining the expression of ten representative genes in the module in 14 diverse apples revealed that at least eight were significantly correlated with anthocyanin variation. MdMYB10 (MDP0000259614) and MdGST (MDP0000252292) were among the most suppressed module member genes in BLO despite being undistinguishable in their corresponding sequences between BLO and KID. Methylation assay of MdMYB10 and MdGST in fruit skin revealed that two regions (MR3 and MR7) in the MdMYB10 promoter exhibited remarkable differences between BLO and KID. In particular, methylation was high and progressively increased alongside fruit development in BLO while was correspondingly low and constant in KID. The methylation levels in both MR3 and MR7 were negatively correlated with anthocyanin content as well as the expression of MdMYB10 and MdGST. Clearly, the collective repression of the 34 genes explains the loss-of-colour in BLO while the methylation in MdMYB10 promoter is likely causal for the mutation.

  9. Transcriptome analysis of an apple (Malus × domestica) yellow fruit somatic mutation identifies a gene network module highly associated with anthocyanin and epigenetic regulation.

    PubMed

    El-Sharkawy, Islam; Liang, Dong; Xu, Kenong

    2015-12-01

    Using RNA-seq, this study analysed an apple (Malus×domestica) anthocyanin-deficient yellow-skin somatic mutant 'Blondee' (BLO) and its red-skin parent 'Kidd's D-8' (KID), the original name of 'Gala', to understand the molecular mechanisms underlying the mutation. A total of 3299 differentially expressed genes (DEGs) were identified between BLO and KID at four developmental stages and/or between two adjacent stages within BLO and/or KID. A weighted gene co-expression network analysis (WGCNA) of the DEGs uncovered a network module of 34 genes highly correlated (r=0.95, P=9.0×10(-13)) with anthocyanin contents. Although 12 of the 34 genes in the WGCNA module were characterized and known of roles in anthocyanin, the remainder 22 appear to be novel. Examining the expression of ten representative genes in the module in 14 diverse apples revealed that at least eight were significantly correlated with anthocyanin variation. MdMYB10 (MDP0000259614) and MdGST (MDP0000252292) were among the most suppressed module member genes in BLO despite being undistinguishable in their corresponding sequences between BLO and KID. Methylation assay of MdMYB10 and MdGST in fruit skin revealed that two regions (MR3 and MR7) in the MdMYB10 promoter exhibited remarkable differences between BLO and KID. In particular, methylation was high and progressively increased alongside fruit development in BLO while was correspondingly low and constant in KID. The methylation levels in both MR3 and MR7 were negatively correlated with anthocyanin content as well as the expression of MdMYB10 and MdGST. Clearly, the collective repression of the 34 genes explains the loss-of-colour in BLO while the methylation in MdMYB10 promoter is likely causal for the mutation. PMID:26417021

  10. Transcriptome analysis of an apple (Malus × domestica) yellow fruit somatic mutation identifies a gene network module highly associated with anthocyanin and epigenetic regulation

    PubMed Central

    El-Sharkawy, Islam; Liang, Dong; Xu, Kenong

    2015-01-01

    Using RNA-seq, this study analysed an apple (Malus×domestica) anthocyanin-deficient yellow-skin somatic mutant ‘Blondee’ (BLO) and its red-skin parent ‘Kidd’s D-8’ (KID), the original name of ‘Gala’, to understand the molecular mechanisms underlying the mutation. A total of 3299 differentially expressed genes (DEGs) were identified between BLO and KID at four developmental stages and/or between two adjacent stages within BLO and/or KID. A weighted gene co-expression network analysis (WGCNA) of the DEGs uncovered a network module of 34 genes highly correlated (r=0.95, P=9.0×10–13) with anthocyanin contents. Although 12 of the 34 genes in the WGCNA module were characterized and known of roles in anthocyanin, the remainder 22 appear to be novel. Examining the expression of ten representative genes in the module in 14 diverse apples revealed that at least eight were significantly correlated with anthocyanin variation. MdMYB10 (MDP0000259614) and MdGST (MDP0000252292) were among the most suppressed module member genes in BLO despite being undistinguishable in their corresponding sequences between BLO and KID. Methylation assay of MdMYB10 and MdGST in fruit skin revealed that two regions (MR3 and MR7) in the MdMYB10 promoter exhibited remarkable differences between BLO and KID. In particular, methylation was high and progressively increased alongside fruit development in BLO while was correspondingly low and constant in KID. The methylation levels in both MR3 and MR7 were negatively correlated with anthocyanin content as well as the expression of MdMYB10 and MdGST. Clearly, the collective repression of the 34 genes explains the loss-of-colour in BLO while the methylation in MdMYB10 promoter is likely causal for the mutation. PMID:26417021

  11. New member of the R2R3-MYB transcription factors family in grapevine suppresses the anthocyanin accumulation in the flowers of transgenic tobacco.

    PubMed

    Pérez-Díaz, J Ricardo; Pérez-Díaz, Jorge; Madrid-Espinoza, José; González-Villanueva, Enrique; Moreno, Yerko; Ruiz-Lara, Simón

    2016-01-01

    In grapevine, anthocyanins and proanthocyanidins are the main flavonoids in berries, which are associated to organoleptic properties in red wine such as color and astringency. Flavonoid pathway is specifically regulated at transcriptional level and several R2R3-MYB proteins have shown to act as positive regulators. However, some members of this family have shown to repress the flavonoid biosynthesis. In this work, we present the characterization of VvMYB4-like gene, which encodes a putative transcriptional factor highly expressed in the skin of berries at the pre veraison stage in grapevine. Its over-expression in tobacco resulted in the loss of pigmentation in flowers due a decrease in anthocyanin accumulation. Severity in anthocyanin suppression observed in petals could be associated with the expression level of the VvMYB4-like transgene. Expression analysis of flavonoid structural genes revealed the strong down-regulation of the flavonoid-related genes anthocyanidin synthase (ANS) and dihydroflavonol reductase (DFR) genes and also the reduction of the anthocyanin-related gene UDP glucose:flavonoid 3-O-glucosyl transferase (UFGT), which was dependent of the transgene expression. In addition, expression of VvMYB4-like in the model plant Arabidopsis showed similar results, with the higher down-regulation observed in the AtDFR and AtLDOX genes. These results suggest that VvMYB4-like may play an important role in regulation of anthocyanin biosynthesis in grapevine acting as a transcriptional repressor of flavonoid structural genes. PMID:26497001

  12. Anthocyanin profile of Korean cultivated kidney bean (Phaseolus vulgaris L.).

    PubMed

    Choung, Myoung-Gun; Choi, Byoung-Rourl; An, Young-Nam; Chu, Yong-Ha; Cho, Young-Son

    2003-11-19

    This investigation was conducted to determine the structures and amounts of anthocyanins obtained from seed coats of kidney bean (Phaseolus vulgaris L.) cultivated in Korea. Anthocyanins in the seed coat of kidney bean were extracted with 1% HCl/20% CH(3)OH, and the crude anthocyanin extracts were purified by semipreparative HPLC. Five major anthocyanins were isolated, and their chemical structures were identified by spectroscopic methods (UV-vis, LC/ES-MS, and 1H and 13C NMR). The structures of these five anthocyanins were elucidated as cyanidin 3,5-diglucoside, delphinidin 3-glucoside, cyanidin 3-glucoside, petunidin 3-glucoside, and pelargonidin 3-glucoside. Using RP-HPLC with photodiode array detection, each of the five anthocyanins was separated within 12 min by using a gradient elution. It was proved that the application of RP-HPLC could be an excellent method for determining the composition and contents of anthocyanins in kidney bean. The preponderance of pelargonidin 3-glucoside and delphinidin 3-glucoside are observed in red and black kidney beans, respectively. However, in this study, it is reported for the first time that the contents and composition of anthocyanins in speckled seed depend on the classes of speckle color. The contents of cyanidin 3,5-diglucoside, delphinidin 3-glucoside, cyanidin 3-glucoside, petunidin 3-glucoside, pelargonidin 3-glucoside, and total anthocyanins in seed coats of 16 kidney beans cultivated in Korea were in the ranges of 0-0.04, 0-2.61, 0-0.12, 0-0.17, 0-0.59 and 0-2.78 mg/g of dried seed coats, respectively.

  13. Anthocyanin profile of Korean cultivated kidney bean (Phaseolus vulgaris L.).

    PubMed

    Choung, Myoung-Gun; Choi, Byoung-Rourl; An, Young-Nam; Chu, Yong-Ha; Cho, Young-Son

    2003-11-19

    This investigation was conducted to determine the structures and amounts of anthocyanins obtained from seed coats of kidney bean (Phaseolus vulgaris L.) cultivated in Korea. Anthocyanins in the seed coat of kidney bean were extracted with 1% HCl/20% CH(3)OH, and the crude anthocyanin extracts were purified by semipreparative HPLC. Five major anthocyanins were isolated, and their chemical structures were identified by spectroscopic methods (UV-vis, LC/ES-MS, and 1H and 13C NMR). The structures of these five anthocyanins were elucidated as cyanidin 3,5-diglucoside, delphinidin 3-glucoside, cyanidin 3-glucoside, petunidin 3-glucoside, and pelargonidin 3-glucoside. Using RP-HPLC with photodiode array detection, each of the five anthocyanins was separated within 12 min by using a gradient elution. It was proved that the application of RP-HPLC could be an excellent method for determining the composition and contents of anthocyanins in kidney bean. The preponderance of pelargonidin 3-glucoside and delphinidin 3-glucoside are observed in red and black kidney beans, respectively. However, in this study, it is reported for the first time that the contents and composition of anthocyanins in speckled seed depend on the classes of speckle color. The contents of cyanidin 3,5-diglucoside, delphinidin 3-glucoside, cyanidin 3-glucoside, petunidin 3-glucoside, pelargonidin 3-glucoside, and total anthocyanins in seed coats of 16 kidney beans cultivated in Korea were in the ranges of 0-0.04, 0-2.61, 0-0.12, 0-0.17, 0-0.59 and 0-2.78 mg/g of dried seed coats, respectively. PMID:14611168

  14. Ferulic acid 5-hydroxylase 1 is essential for expression of anthocyanin biosynthesis-associated genes and anthocyanin accumulation under photooxidative stress in Arabidopsis.

    PubMed

    Maruta, Takanori; Noshi, Masahiro; Nakamura, Maki; Matsuda, Shun; Tamoi, Masahiro; Ishikawa, Takahiro; Shigeoka, Shigeru

    2014-04-01

    Anthocyanins are important for preventing photoinhibition and photodamage. By comprehensive reverse genetic analysis of chloroplast-produced H2O2-responsive genes, we isolated here an anthocyanin-deficient mutant under photooxidative stress, which lacked ferulate 5-hydroxylase 1 (FAH1) involved in the phenylpropanoid pathway. Interestingly, the expression of anthocyanin biosynthesis-associated genes was also inhibited in this mutant. These findings suggest that FAH1 is essential for expression of anthocyanin biosynthesis-associated genes and anthocyanin accumulation under photooxidative stress in Arabidopsis. Furthermore, we found that estrogen-inducible silencing of thylakoid membrane-bound ascorbate peroxidase, which is a major H2O2-scavenging enzyme in chloroplasts, enhances the expression of FAH1 and anthocyanin biosynthesis-associated genes and accumulation of anthocyanin without any application of stress. Thus, it is likely that chloroplastic H2O2 activates FAH1 expression to induce anthocyanin accumulation for protecting cells from photooxidative stress.

  15. Anthocyanin accumulation and expression of anthocyanin biosynthetic genes in radish (Raphanus sativus).

    PubMed

    Park, Nam Il; Xu, Hui; Li, Xiaohua; Jang, In Hyuk; Park, Suhyoung; Ahn, Gil Hwan; Lim, Yong Pyo; Kim, Sun Ju; Park, Sang Un

    2011-06-01

    Radish [Raphanus sativus (Rs)] is an important dietary vegetable in Asian countries, especially China, Japan, and Korea. To elucidate the molecular mechanisms of anthocyanin accumulation in radish, the gene expression of enzymes directly involved in anthocyanin biosynthesis was analyzed. These genes include phenylalanine ammonia lyase (PAL), cinnamate 4-hydroxylase (C4H), 4-coumarate-CoA ligase (4CL), chalcone synthase (CHS), chalcone isomerase (CHI), flavanone 3-hydroxylase (F3H), dihydroflavonol reductase (DFR), and anthocyanidin synthase (ANS). RsDFR and RsANS were found to accumulate in the flesh or skin of two radish cultivars (Man Tang Hong and Hong Feng No.1). Radish skin contained higher CHS, CHI, and F3H transcript levels than radish flesh in all three cultivars. In the red radish, 16 anthocyanins were separated and identified by high-performance liquid chromatography (HPLC) and elctrospray ionization-tandem mass spectrometry (ESI-MS/MS). Some of them were acylated with coumaroyl, malonoyl, feruoyl, and caffeoyl moieties. Furthermore (-)-epicatechin and ferulic acid were also identified in the three cultivars.

  16. Major anthocyanins from purple asparagus (Asparagus officinalis).

    PubMed

    Sakaguchi, Yumi; Ozaki, Yukio; Miyajima, Ikuo; Yamaguchi, Masaatsu; Fukui, Yuko; Iwasa, Keiko; Motoki, Satoru; Suzuki, Takashi; Okubo, Hiroshi

    2008-05-01

    Two major anthocyanins (A1 and A2) were isolated from peels of the spears of Asparagus officinalis cv. Purple Passion. They were purified by column, paper and high-performance liquid chromatographic separations, and their structures were elucidated by high-resolution Fourier transform ion cyclotron resonance mass spectrometry (HR-FT-ICR MS), 1H, 13C and two-dimensional NMR spectroscopic analyses and either acid or alkaline hydrolysis, respectively. A1 was identified as cyanidin 3-[3''-(O-beta-d-glucopyranosyl)-6''-(O-alpha-l-rhamnopyranosyl)-O-beta-d-glucopyranoside], whereas A2 was cyanidin 3-rutinoside, which is widely distributed in higher plants. Oxygen radical absorbance capacity (ORAC) assays proved their high antioxidant activities. PMID:18406435

  17. The use of phenylmethylsulfonyl fluoride in the study of catabolite inactivation and repression in intact cells of Saccharomyces cervisiae.

    PubMed

    Grossmann, M K

    1980-02-01

    Catabolite inactivation of fructose-1,6-bisphosphatase, isocitrate lyase, phosphoenolpruvate carboxykinase and malate dehydrogenase in intact cells could be prevented by phenylmethylsulfonyl fluoride added 40 min prior to the addition of glucose. Protein synthesis, fermentative and respiratory activity and catabolite repression were not affected. Elimination of catabolite inactivation by the addition of PMSF revealed that catabolite repression started at different times for different enzyme. PMID:6245626

  18. The role of acyl-glucose in anthocyanin modifications.

    PubMed

    Sasaki, Nobuhiro; Nishizaki, Yuzo; Ozeki, Yoshihiro; Miyahara, Taira

    2014-11-14

    Higher plants can produce a wide variety of anthocyanin molecules through modification of the six common anthocyanin aglycons that they present. Thus, hydrophilic anthocyanin molecules can be formed and stabilized by glycosylation and acylation. Two types of glycosyltransferase (GT) and acyltransferase (AT) have been identified, namely cytoplasmic GT and AT and vacuolar GT and AT. Cytoplasmic GT and AT utilize UDP-sugar and acyl-CoA as donor molecules, respectively, whereas both vacuolar GT and AT use acyl-glucoses as donor molecules. In carnation plants, vacuolar GT uses aromatic acyl-glucoses as the glucose donor in vivo; independently, vacuolar AT uses malylglucose, an aliphatic acyl-glucose, as the acyl-donor. In delphinium and Arabidopsis, p-hydroxybenzoylglucose and sinapoylglucose are used in vivo as bi-functional donor molecules by vacuolar GT and AT, respectively. The evolution of these enzymes has allowed delphinium and Arabidopsis to utilize unique donor molecules for production of highly modified anthocyanins.

  19. New acylated anthocyanins from purple yam and their antioxidant activity.

    PubMed

    Moriya, Chiemi; Hosoya, Takahiro; Agawa, Sayuri; Sugiyama, Yasumasa; Kozone, Ikuko; Shin-Ya, Kazuo; Terahara, Norihiko; Kumazawa, Shigenori

    2015-01-01

    Purple yam (Dioscorea alata L.), which is widely distributed in tropical and subtropical regions, is characterized by its color and viscosity. Previous studies have shown that purple yams contain a variety of acylated anthocyanins that exhibit higher levels of antioxidant activity than the corresponding nonacylated compounds. In this study, the pigments found in purple yams from the Philippines (D. alata) were isolated and evaluated in terms of antioxidant activity. Four new acylated anthocyanins, alanins (1-4) were isolated from the MeOH extracts of purple yam, which were subsequently determined to be cyanidin (1, 2, and 4) and peonidin (3) type compounds, along with four known anthocyanins (5-8). The structures of 1-4 were determined by spectroscopic methods, including NMR and MS analyses. The antioxidant activities of anthocyanins 1-8 were investigated using oxygen radical absorbing capacity and ferric reducing antioxidant power assays. PMID:25848974

  20. Androgen receptor repression of gonadotropin-releasing hormone gene transcription via enhancer 1.

    PubMed

    Brayman, Melissa J; Pepa, Patricia A; Mellon, Pamela L

    2012-11-01

    Gonadotropin-releasing hormone (GnRH) plays a major role in the hypothalamic-pituitary-gonadal (HPG) axis, and synthesis and secretion of GnRH are regulated by gonadal steroid hormones. Disruptions in androgen levels are involved in a number of reproductive defects, including hypogonadotropic hypogonadism and polycystic ovarian syndrome. Androgens down-regulate GnRH mRNA synthesis in vivo and in vitro via an androgen receptor (AR)-dependent mechanism. Methyltrienolone (R1881), a synthetic AR agonist, represses GnRH expression through multiple sites in the proximal promoter. In this study, we show AR also represses GnRH transcription via the major enhancer (GnRH-E1). A multimer of the -1800/-1766 region was repressed by R1881 treatment. Mutation of two bases, -1792 and -1791, resulted in decreased basal activity and a loss of AR-mediated repression. AR bound to the -1796/-1791 sequence in electrophoretic mobility shift assays, indicating a direct interaction with DNA or other transcription factors in this region. We conclude that AR repression of GnRH-E1 acts via multiple AR-responsive regions, including the site at -1792/-1791.

  1. Androgen receptor repression of gonadotropin-releasing hormone gene transcription via enhancer 1.

    PubMed

    Brayman, Melissa J; Pepa, Patricia A; Mellon, Pamela L

    2012-11-01

    Gonadotropin-releasing hormone (GnRH) plays a major role in the hypothalamic-pituitary-gonadal (HPG) axis, and synthesis and secretion of GnRH are regulated by gonadal steroid hormones. Disruptions in androgen levels are involved in a number of reproductive defects, including hypogonadotropic hypogonadism and polycystic ovarian syndrome. Androgens down-regulate GnRH mRNA synthesis in vivo and in vitro via an androgen receptor (AR)-dependent mechanism. Methyltrienolone (R1881), a synthetic AR agonist, represses GnRH expression through multiple sites in the proximal promoter. In this study, we show AR also represses GnRH transcription via the major enhancer (GnRH-E1). A multimer of the -1800/-1766 region was repressed by R1881 treatment. Mutation of two bases, -1792 and -1791, resulted in decreased basal activity and a loss of AR-mediated repression. AR bound to the -1796/-1791 sequence in electrophoretic mobility shift assays, indicating a direct interaction with DNA or other transcription factors in this region. We conclude that AR repression of GnRH-E1 acts via multiple AR-responsive regions, including the site at -1792/-1791. PMID:22877652

  2. Six new acylated anthocyanins from red radish (Raphanus sativus).

    PubMed

    Tamura, Satoru; Tsuji, Kouji; Yongzhen, Piao; Ohnishi-Kameyama, Mayumi; Murakami, Nobutoshi

    2010-09-01

    Six new acylated anthocyanins (1-6) were isolated along with the three known congeners (7-9) from the fresh roots of red radishes (Raphanus sativus L.) cultivated by our group. Their chemical structures were elucidated by spectroscopic properties. Among the six new anthocyanins, the five constituents (1, 2, 4-6) were shown to contain the malonyl function at 6-OH in the glucopyranosyl residue linked to C-5 in the pelargonidin nucleus.

  3. Characterization, quantification, and bioactivities of anthocyanins in Cornus species.

    PubMed

    Seeram, Navindra P; Schutzki, Robert; Chandra, Amitabh; Nair, Muraleedharan G

    2002-04-24

    Cornus mas, Cornus officinalis, Cornus controversa, and Cornus kousa (Cornaceae) bear edible fruits that are consumed in parts of Europe and Asia. This study undertook the investigation of the presence and levels of anthocyanins in the fruits of these Cornus species by HPLC. The anthocyanins present in Cornelian cherries, C. mas, are delphinidin 3-O-beta-galactopyranoside (1), cyanidin 3-O-beta-galactopyranoside (2), and pelargonidin 3-O-beta-galactopyranoside (3). C. officinalis contains only anthocyanins 1-3, similar to C. mas, but in different proportions. However, C. controversa contains anthocyanins 1-3 among other anthocyanins, but Chinese dogwood, C. kousa, did not contain 1-3. The contents of pure anthocyanins 1, 2, and 3 in 1 kg of fresh fruits of C. mas, C. officinalis, and C. controversa were 280, 1079, and 710 ppm; 11, 77, and 230 ppm; and 600, 1000, and 700 ppm, respectively. In cyclooxygenase (COX)-I and -II enzyme inhibitory assays, anthocyanins 1-3 (all 40 microM) showed activities of 9.2 and 11.7%; 7.6 and 12.4%; and 5.3 and 7.8%, respectively, compared to Naproxen (54.3 and 41.3%; 10 microM), ibuprofen (47.5 and 39.8%; 10 microM), Celebrex (46.2 and 66.3%; 1.67 ppm), and Vioxx (23.8 and 88.1%, 1.67 ppm). In the antioxidant assay, anthocyanins 1-3 (all 40 microM) showed activities of 70.2, 60.1, and 40.3%, respectively. At 10 microM concentration, commercial synthetic antioxidants tert-butylhydroquinone, butylated hydroxytoluene, butylated hydroxyanisole, and vitamin E gave 83.2, 79.7, 82.1, and 10.2% of antioxidant activity, respectively. PMID:11958615

  4. Anthocyanin Vacuolar Inclusions Form by a Microautophagy Mechanism.

    PubMed

    Chanoca, Alexandra; Kovinich, Nik; Burkel, Brian; Stecha, Samantha; Bohorquez-Restrepo, Andres; Ueda, Takashi; Eliceiri, Kevin W; Grotewold, Erich; Otegui, Marisa S

    2015-09-01

    Anthocyanins are flavonoid pigments synthesized in the cytoplasm and stored inside vacuoles. Many plant species accumulate densely packed, 3- to 10-μm diameter anthocyanin deposits called anthocyanin vacuolar inclusions (AVIs). Despite their conspicuousness and importance in organ coloration, the origin and nature of AVIs have remained controversial for decades. We analyzed AVI formation in cotyledons of different Arabidopsis thaliana genotypes grown under anthocyanin inductive conditions and in purple petals of lisianthus (Eustoma grandiorum). We found that cytoplasmic anthocyanin aggregates in close contact with the vacuolar surface are directly engulfed by the vacuolar membrane in a process reminiscent of microautophagy. The engulfed anthocyanin aggregates are surrounded by a single membrane derived from the tonoplast and eventually become free in the vacuolar lumen like an autophagic body. Neither endosomal/prevacuolar trafficking nor the autophagy ATG5 protein is involved in the formation of AVIs. In Arabidopsis, formation of AVIs is promoted by both an increase in cyanidin 3-O-glucoside derivatives and by depletion of the glutathione S-transferase TT19. We hypothesize that this novel microautophagy mechanism also mediates the transport of other flavonoid aggregates into the vacuole. PMID:26342015

  5. Anthocyanin inheritance and instability in purple basil (Ocimum basilicum L.).

    PubMed

    Phippen, W B; Simon, J E

    2000-01-01

    The instability of the purple pigments (anthocyanins) in purple basil varieties (Ocimum basilicum L.) limits their use as ornamental plants and as a potential anthocyanin source. Several self-pollinated generations of all purple plants were unsuccessful in stabilizing anthocyanin expression. In this study we investigated the inheritance and stability patterns of leaf traits using the Purple Ruffles variety. The results from the complete diallele crosses indicated anthocyanin expression in vegetative tissue is controlled by two dominant genes and ruffled leaf texture is controlled by a single recessive gene. Genes controlling leaf margin and leaf base structures were tightly linked to leaf texture. Essential oil production and oil constituents in leaves did not change as a result of the reversion in color. Color stability in cuttings was affected by the environment and the location where cuttings were taken. An accumulation of secondary metabolites (apigenin, genistein, and kaempferol) in green-reverted sectors on purple leaves was detected using reverse-phase high-performance liquid chromatography (HPLC) analysis; this suggested a potential block in the anthocyanin pathway. We hypothesize the reversion mutation is occurring in an anthocyanin regulatory gene.

  6. Transcriptional control of floral anthocyanin pigmentation in monkeyflowers (Mimulus).

    PubMed

    Yuan, Yao-Wu; Sagawa, Janelle M; Frost, Laura; Vela, James P; Bradshaw, Harvey D

    2014-12-01

    A molecular description of the control of floral pigmentation in a multi-species group displaying various flower color patterns is of great interest for understanding the molecular bases of phenotypic diversification and pollinator-mediated speciation. Through transcriptome profiling, mutant analyses and transgenic experiments, we aim to establish a 'baseline' floral anthocyanin regulation model in Mimulus lewisii and to examine the different ways of tinkering with this model in generating the diversity of floral anthocyanin patterns in other Mimulus species. We find one WD40 and one bHLH gene controlling anthocyanin pigmentation in the entire corolla of M. lewisii and two R2R3-MYB genes, PELAN and NEGAN, controlling anthocyanin production in the petal lobe and nectar guide, respectively. The autoregulation of NEGAN might be a critical property to generate anthocyanin spots. Independent losses of PELAN expression (via different mechanisms) explain two natural yellow-flowered populations of M. cardinalis (typically red-flowered). The NEGAN ortholog is the only anthocyanin-activating MYB expressed in the M. guttatus flowers. The mutant lines and transgenic tools available for M. lewisii will enable gene-by-gene replacement experiments to dissect the genetic and developmental bases of more complex floral color patterns, and to test hypotheses on phenotypic evolution in general.

  7. Anthocyanin Vacuolar Inclusions Form by a Microautophagy Mechanism

    PubMed Central

    Chanoca, Alexandra; Ueda, Takashi; Grotewold, Erich

    2015-01-01

    Anthocyanins are flavonoid pigments synthesized in the cytoplasm and stored inside vacuoles. Many plant species accumulate densely packed, 3- to 10-μm diameter anthocyanin deposits called anthocyanin vacuolar inclusions (AVIs). Despite their conspicuousness and importance in organ coloration, the origin and nature of AVIs have remained controversial for decades. We analyzed AVI formation in cotyledons of different Arabidopsis thaliana genotypes grown under anthocyanin inductive conditions and in purple petals of lisianthus (Eustoma grandiorum). We found that cytoplasmic anthocyanin aggregates in close contact with the vacuolar surface are directly engulfed by the vacuolar membrane in a process reminiscent of microautophagy. The engulfed anthocyanin aggregates are surrounded by a single membrane derived from the tonoplast and eventually become free in the vacuolar lumen like an autophagic body. Neither endosomal/prevacuolar trafficking nor the autophagy ATG5 protein is involved in the formation of AVIs. In Arabidopsis, formation of AVIs is promoted by both an increase in cyanidin 3-O-glucoside derivatives and by depletion of the glutathione S-transferase TT19. We hypothesize that this novel microautophagy mechanism also mediates the transport of other flavonoid aggregates into the vacuole. PMID:26342015

  8. Novel thigmomorphogenetic responses in Carica papaya: touch decreases anthocyanin levels and stimulates petiole cork outgrowths

    PubMed Central

    Porter, Brad W.; Zhu, Yun J.; Webb, David T.; Christopher, David A.

    2009-01-01

    Background and Aims Because of its rapid growth rate, relative ease of transformation, sequenced genome and low gene number relative to Arabidopsis, the tropical fruit tree, Carica papaya, can serve as a complementary genetic model for complex traits. Here, new phenotypes and touch-regulated gene homologues have been identified that can be used to advance the understanding of thigmomorphogenesis, a multigenic response involving mechanoreception and morphological change. Methods Morphological alterations were quantified, and microscopy of tissue was conducted. Assays for hypocotyl anthocyanins, lignin and chlorophyll were performed, and predicted genes from C. papaya were compared with Arabidopsis touch-inducible (TCH) and Mechanosensitive channel of Small conductance-like genes (MscS-like or MSL). In addition, the expression of two papaya TCH1 homologues was characterized. Key Results On the abaxial side of petioles, treated plants were found to have novel, hypertrophic outgrowths associated with periderm and suberin. Touched plants also had higher lignin, dramatically less hypocotyl anthocyanins and chlorophyll, increased hypocotyl diameter, and decreased leaf width, stem length and root fresh weight. Papaya was found to have fewer MSL genes than Arabidopsis, and four touch-regulated genes in Arabidopsis had no counterparts in papaya. Water-spray treatment was found to enhance the expression of two papaya TCH1 homologues whereas induction following touch was only slightly correlated. Conclusions The novel petiole outgrowths caused by non-wounding, mechanical perturbation may be the result of hardening mechanisms, including added lignin, providing resistance against petiole movement. Inhibition of anthocyanin accumulation following touch, a new phenotypic association, may be caused by diversion of p-coumaroyl CoA away from chalcone synthase for lignin synthesis. The absence of MSL and touch-gene homologues indicates that papaya may have a smaller set of touch

  9. Mitosis-associated repression in development.

    PubMed

    Esposito, Emilia; Lim, Bomyi; Guessous, Ghita; Falahati, Hanieh; Levine, Michael

    2016-07-01

    Transcriptional repression is a pervasive feature of animal development. Here, we employ live-imaging methods to visualize the Snail repressor, which establishes the boundary between the presumptive mesoderm and neurogenic ectoderm of early Drosophila embryos. Snail target enhancers were attached to an MS2 reporter gene, permitting detection of nascent transcripts in living embryos. The transgenes exhibit initially broad patterns of transcription but are refined by repression in the mesoderm following mitosis. These observations reveal a correlation between mitotic silencing and Snail repression. We propose that mitosis and other inherent discontinuities in transcription boost the activities of sequence-specific repressors, such as Snail. PMID:27401553

  10. PH4 of Petunia Is an R2R3 MYB Protein That Activates Vacuolar Acidification through Interactions with Basic-Helix-Loop-Helix Transcription Factors of the Anthocyanin Pathway[W

    PubMed Central

    Quattrocchio, Francesca; Verweij, Walter; Kroon, Arthur; Spelt, Cornelis; Mol, Joseph; Koes, Ronald

    2006-01-01

    The Petunia hybrida genes ANTHOCYANIN1 (AN1) and AN2 encode transcription factors with a basic-helix-loop-helix (BHLH) and a MYB domain, respectively, that are required for anthocyanin synthesis and acidification of the vacuole in petal cells. Mutation of PH4 results in a bluer flower color, increased pH of petal extracts, and, in certain genetic backgrounds, the disappearance of anthocyanins and fading of the flower color. PH4 encodes a MYB domain protein that is expressed in the petal epidermis and that can interact, like AN2, with AN1 and the related BHLH protein JAF13 in yeast two-hybrid assays. Mutation of PH4 has little or no effect on the expression of structural anthocyanin genes but strongly downregulates the expression of CAC16.5, encoding a protease-like protein of unknown biological function. Constitutive expression of PH4 and AN1 in transgenic plants is sufficient to activate CAC16.5 ectopically. Together with the previous finding that AN1 domains required for anthocyanin synthesis and vacuolar acidification can be partially separated, this suggests that AN1 activates different pathways through interactions with distinct MYB proteins. PMID:16603655

  11. Topical treatment of oral lichen planus with anthocyanins

    PubMed Central

    Di Fabio, Amanda; Salomón, Susana; Lanfranchi, Héctor

    2014-01-01

    Background: Oxidative stress is involved in oral lichen planus (OLP) pathogenesis; meanwhile anthocyanins are natural antioxidants present in grapes skin. Objectives: The aim of this research was to verify the utility of anthocyanins, extracted from grapes skin, for the local treatment of oral lichen planus and to compare it with clobetasol propionate- neomycin -nystatin cream (CP-NN). Study Design: Prospective, non-randomized study, with control group. Fifty-two patients with OLP were included. We divided patients into two categories: erosive oral lichen planus (EOLP) and non erosive oral lichen planus (NEOLP). 38 had EOLP (17 cases and 21 controls) and 14 presented NEOLP types (9 cases and 5 controls).Cases received local treatment with anthocyanins from grapes and controls, were treated with CP-NN. The clinical evolution of patients was followed up during six months. Results: The patients had a therapeutic response with anthocyanins. This was better than CP-NN treatment for patients with EOLP, in improving the involvement score of the oral mucosa and in the morphometric study of the affected areas. In EOLP there were no statistically significant differences in: therapeutic response time, the evolution of pain, or the relapse rate between the two groups. With respect to the treatment of NEOLP there was improved pain relief in the group treated with anthocyanins. This was not observed with CP-NN. The resting analized variables showed no significant difference with both treatments. Conclusions: OLP has a favorable response to local treatment with anthocyanins from grapes. We found an equal to or better response than with CP-NN treatment. Many of our patients have systemic diseases, which may contraindicate the use of steroids. With regard to this particular group, the use of this natural antioxidant present in the diet is considered advantageous. Key words:Anthocyanins, antioxidants, chemoprevention, morphometry, oral lichen, oxidative stress. PMID:24880442

  12. Primal repression: clinical and theoretical aspects.

    PubMed

    Kinston, W; Cohen, J

    1986-01-01

    Primal repression, long an obscure and unusable concept, has been given a precise place in a recent re-working of the theory of repression (Cohen & Kinston, 1984); and this paper specifically examines its properties and presentation. Primal repression refers to an absence of psychic structure which can be made good in the process of emotional growth. It is a part of the mind where trauma persists; and it has a close connexion to the unrepressed unconscious. Direct emergence of primal repression is a threat to life and its activation is therefore risky. During psychoanalysis, primal repression is normally avoided by object-narcissism buttressed by neurotic defences, but it may be reached and worked with in the presence of a non-internalizable valuing and nurturing relationship which we label 'primary relatedness'. This relation is therefore the interactional context for emotional growth. Numerous clinical examples are provided to demonstrate characteristic features of this region of the mind as seen in psychoanalyses. Vignettes illustrate the experiences of patient and analyst as primary relatedness is established; the consequent re-emergence of traumatic states and unmet needs, often initially in the form of severe physical and psychological deterioration; primitive forms of symbolization in the course of repairing primal repression; and the role of action in emotional growth. PMID:2427464

  13. In vitro and in vivo biological activities of anthocyanins from Nitraria tangutorun Bobr. fruits.

    PubMed

    Ma, Tao; Hu, Na; Ding, Chenxi; Zhang, Qiulong; Li, Wencong; Suo, Yourui; Wang, Honglun; Bai, Bo; Ding, Chenxu

    2016-03-01

    Anthocyanins are the main compounds in Nitraria tangutorun Bobr. The enrichment and purification of anthocyanins on macroporous resins were investigated. Regarding anthocyanin purification, static adsorption and desorption were studied. The optimal experimental conditions were the following: resin type: X-5; static adsorption time: 6h; desorption solution: ethanol-water-HCl (80:19:1, V/V/V; pH 1); desorption time: 40min. Furthermore, the in vitro and in vivo biological activities of the anthocyanins were evaluated. The anthocyanins showed ideal scavenging effects on free radicals in vitro, especially on 1,1-diphenyl-2-picrylhydrazyl (DPPH) and hydroxyl free radical (OH). In the animal experiment, blood lipid metabolism of hyperlipidemia rats was regulated by anthocyanin contents. The superoxide dismutase (SOD) activity and the total antioxidant capacity (TAC) of hyperlipidemia rats were also improved by anthocyanins. These results showed that anthocyanins from N. tangutorun Bobr. fruits had potential biological activities in vivo as well as in vitro.

  14. In vitro and in vivo biological activities of anthocyanins from Nitraria tangutorun Bobr. fruits.

    PubMed

    Ma, Tao; Hu, Na; Ding, Chenxi; Zhang, Qiulong; Li, Wencong; Suo, Yourui; Wang, Honglun; Bai, Bo; Ding, Chenxu

    2016-03-01

    Anthocyanins are the main compounds in Nitraria tangutorun Bobr. The enrichment and purification of anthocyanins on macroporous resins were investigated. Regarding anthocyanin purification, static adsorption and desorption were studied. The optimal experimental conditions were the following: resin type: X-5; static adsorption time: 6h; desorption solution: ethanol-water-HCl (80:19:1, V/V/V; pH 1); desorption time: 40min. Furthermore, the in vitro and in vivo biological activities of the anthocyanins were evaluated. The anthocyanins showed ideal scavenging effects on free radicals in vitro, especially on 1,1-diphenyl-2-picrylhydrazyl (DPPH) and hydroxyl free radical (OH). In the animal experiment, blood lipid metabolism of hyperlipidemia rats was regulated by anthocyanin contents. The superoxide dismutase (SOD) activity and the total antioxidant capacity (TAC) of hyperlipidemia rats were also improved by anthocyanins. These results showed that anthocyanins from N. tangutorun Bobr. fruits had potential biological activities in vivo as well as in vitro. PMID:26471558

  15. Anthocyanins are bioavailable in humans following an acute dose of cranberry juice

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Research suggests that anthocyanins from berry fruit may affect a variety of physiological responses, including endothelial function, but little information is available regarding the pharmacokinetics of these flavonoids in humans. To determine the pharmacokinetics of cranberry anthocyanins a study ...

  16. The anthocyanin reduced tomato mutant demonstrates the role of flavonols in tomato lateral root and root hair development.

    PubMed

    Maloney, Gregory S; DiNapoli, Kathleen T; Muday, Gloria K

    2014-10-01

    This study utilized tomato (Solanum lycopersicum) mutants with altered flavonoid biosynthesis to understand the impact of these metabolites on root development. The mutant anthocyanin reduced (are) has a mutation in the gene encoding FLAVONOID 3-HYDROXYLASE (F3H), the first step in flavonol synthesis, and accumulates higher concentrations of the F3H substrate, naringenin, and lower levels of the downstream products kaempferol, quercetin, myricetin, and anthocyanins, than the wild type. Complementation of are with the p35S:F3H transgene reduced naringenin and increased flavonols to wild-type levels. The initiation of lateral roots is reduced in are, and p35S:F3H complementation restores wild-type root formation. The flavonoid mutant anthocyanin without has a defect in the gene encoding DIHYDROFLAVONOL REDUCTASE, resulting in elevated flavonols and the absence of anthocyanins and displays increased lateral root formation. These results are consistent with a positive role of flavonols in lateral root formation. The are mutant has increased indole-3-acetic acid transport and greater sensitivity to the inhibitory effect of the auxin transport inhibitor naphthylphthalamic acid on lateral root formation. Expression of the auxin-induced reporter (DR5-β-glucuronidase) is reduced in initiating lateral roots and increased in primary root tips of are. Levels of reactive oxygen species are elevated in are root epidermal tissues and root hairs, and are forms more root hairs, consistent with a role of flavonols as antioxidants that modulate root hair formation. Together, these experiments identify positive roles of flavonols in the formation of lateral roots and negative roles in the formation of root hairs through the modulation of auxin transport and reactive oxygen species, respectively. PMID:25006027

  17. Systematic Review of Anthocyanins and Markers of Cardiovascular Disease

    PubMed Central

    Wallace, Taylor C.; Slavin, Margaret; Frankenfeld, Cara L.

    2016-01-01

    Anthocyanins are dietary flavonoids commonly consumed in the diet, which have been suggested to have a preventative effect on cardiovascular disease (CVD) development among epidemiological studies. We systematically reviewed randomized controlled trials (RCTs) testing the effects of purified anthocyanins and anthocyanin-rich extracts on markers of CVD (triglycerides, total cholesterol, low-density lipoprotein (LDL) cholesterol, high-density lipoprotein (HDL) cholesterol, and blood pressure) in both healthy and diseased populations. Eligible studies included RCTs of adults published in English. We searched PubMed, Web of Science Core Collection, and BIOSIS Previews for relevant articles from inception until 1 July 2014. Twelve RCTs representing 10 studies were included in this review. Supplementation with anthocyanins significantly improved LDL cholesterol among diseased individuals or those with elevated biomarkers. Supplementation did not significantly affect other markers of CVD in either healthy individuals or those with elevated markers. No adverse effects of anthocyanins were reported across studies at levels up to 640 mg/day. Limitations of trials in the qualitative analyses include short trial duration and large variability in the dose administered within the trials. Longer-duration trials assessing dose response are needed to adequately determine whether an effect of supplementation exists. PMID:26761031

  18. Systematic Review of Anthocyanins and Markers of Cardiovascular Disease.

    PubMed

    Wallace, Taylor C; Slavin, Margaret; Frankenfeld, Cara L

    2016-01-01

    Anthocyanins are dietary flavonoids commonly consumed in the diet, which have been suggested to have a preventative effect on cardiovascular disease (CVD) development among epidemiological studies. We systematically reviewed randomized controlled trials (RCTs) testing the effects of purified anthocyanins and anthocyanin-rich extracts on markers of CVD (triglycerides, total cholesterol, low-density lipoprotein (LDL) cholesterol, high-density lipoprotein (HDL) cholesterol, and blood pressure) in both healthy and diseased populations. Eligible studies included RCTs of adults published in English. We searched PubMed, Web of Science Core Collection, and BIOSIS Previews for relevant articles from inception until 1 July 2014. Twelve RCTs representing 10 studies were included in this review. Supplementation with anthocyanins significantly improved LDL cholesterol among diseased individuals or those with elevated biomarkers. Supplementation did not significantly affect other markers of CVD in either healthy individuals or those with elevated markers. No adverse effects of anthocyanins were reported across studies at levels up to 640 mg/day. Limitations of trials in the qualitative analyses include short trial duration and large variability in the dose administered within the trials. Longer-duration trials assessing dose response are needed to adequately determine whether an effect of supplementation exists. PMID:26761031

  19. Antioxidative and Cardioprotective Properties of Anthocyanins from Defatted Dabai Extracts

    PubMed Central

    Khoo, Hock Eng; Azlan, Azrina; Nurulhuda, M. Halid; Ismail, Amin; Abas, Faridah; Hamid, Muhajir; Roowi, Suri

    2013-01-01

    This study aimed to determine anthocyanins and their antioxidative and cardioprotective properties in defatted dabai parts. Anthocyanins in crude extracts and extract fractions of defatted dabai peel and pericarp were quantified using UHPLC, while their antioxidant capacity and oxidative stress inhibition ability were evaluated by using DPPH and CUPRAC assays as well as linoleic acid oxidation system, hemoglobin oxidation, and PARP-1 inhibition ELISA. Cardioprotective effect of the defatted dabai peel extract was evaluated using hypercholesterolemic-induced New Zealand white rabbits. Six anthocyanins were detected in the defatted dabai peel, with the highest antioxidant capacities and oxidative stress inhibition effect compared to the other part. The defatted dabai peel extract has also inhibited lipid peroxidation (plasma MDA) and elevated cellular antioxidant enzymes (SOD and GPx) in the tested animal model. Major anthocyanin (cyanidin-3-glucoside) and other anthocyanins (pelargonidin-3-glucoside, malvidin-3-glucoside, cyanidin-3-galactoside, cyanidin-3-arabinoside, and peonidin-3-glucoside) detected in the defatted dabai peel are potential future nutraceuticals with promising medicinal properties. PMID:24368926

  20. Genetic Control and Evolution of Anthocyanin Methylation1[W

    PubMed Central

    Provenzano, Sofia; Spelt, Cornelis; Hosokawa, Satoko; Nakamura, Noriko; Brugliera, Filippa; Demelis, Linda; Geerke, Daan P.; Schubert, Andrea; Tanaka, Yoshikazu; Quattrocchio, Francesca; Koes, Ronald

    2014-01-01

    Anthocyanins are a chemically diverse class of secondary metabolites that color most flowers and fruits. They consist of three aromatic rings that can be substituted with hydroxyl, sugar, acyl, and methyl groups in a variety of patterns depending on the plant species. To understand how such chemical diversity evolved, we isolated and characterized METHYLATION AT THREE2 (MT2) and the two METHYLATION AT FIVE (MF) loci from Petunia spp., which direct anthocyanin methylation in petals. The proteins encoded by MT2 and the duplicated MF1 and MF2 genes and a putative grape (Vitis vinifera) homolog Anthocyanin O-Methyltransferase1 (VvAOMT1) are highly similar to and apparently evolved from caffeoyl-Coenzyme A O-methyltransferases by relatively small alterations in the active site. Transgenic experiments showed that the Petunia spp. and grape enzymes have remarkably different substrate specificities, which explains part of the structural anthocyanin diversity in both species. Most strikingly, VvAOMT1 expression resulted in the accumulation of novel anthocyanins that are normally not found in Petunia spp., revealing how alterations in the last reaction can reshuffle the pathway and affect (normally) preceding decoration steps in an unanticipated way. Our data show how variations in gene expression patterns, loss-of-function mutations, and alterations in substrate specificities all contributed to the anthocyanins’ structural diversity. PMID:24830298

  1. Isolation and Characterization of Anthocyanins from Hibiscus sabdariffa Flowers.

    PubMed

    Grajeda-Iglesias, Claudia; Figueroa-Espinoza, Maria C; Barouh, Nathalie; Baréa, Bruno; Fernandes, Ana; de Freitas, Victor; Salas, Erika

    2016-07-22

    The intense red-colored Hibiscus sabdariffa flowers are an inexpensive source of anthocyanins with potential to be used as natural, innocuous, and health-beneficial colorants. An anthocyanin-rich extract from hibiscus flowers was obtained by ultrasound-assisted extraction. By a single-step process fractionation using a Sep-Pak C18 cartridge, the main hibiscus anthocyanins, delphinidin-3-O-sambubioside (Dp-samb) and cyanidin-3-O-sambubioside (Cy-samb), were separated and then characterized via NMR and HPLC-ESIMS data. Since Dp-samb was the most abundant anthocyanin identified in the extract, its colorant properties were studied by the pH jumps method, which allowed the calculation of the single acid-base equilibrium (pK'a 2.92), the acidity (pKa 3.70), and the hydration constants (pKh 3.02). Moreover, by using size-exclusion chromatography, new cyanidin-derived anthocyanins (with three or more sugar units) were successfully identified and reported for the first time in the hibiscus extract. PMID:27312226

  2. Analysis of interactions between heterologously produced bHLH and MYB proteins that regulate anthocyanin biosynthesis: quantitative interaction kinetics by Microscale Thermophoresis.

    PubMed

    Nemie-Feyissa, Dugassa; Heidari, Behzad; Blaise, Mickael; Lillo, Cathrine

    2015-03-01

    The two Arabidopsis basic-helix-loop-helix transcription factors GLABRA3 (GL3) and ENHANCER OF GLABRA3 (EGL3) are positive regulators of anthocyanin biosynthesis, and form protein complexes (MBW complexes) with various R2R3 MYB transcription factors and a WD40 repeat protein TRANSPARENT TESTA GLABROUS1 (TTG1). In earlier studies, GL3, in contrast to EGL3, was shown to be essential for accumulation of anthocyanins in response to nitrogen depletion. This could not be fully explained by the strong induction of GL3 in response to nitrogen depletion because the EGL3 transcripts were constitutively at a relatively high level and transcripts levels of the two genes were similar under nitrogen depletion. Here the GL3 and EGL3 proteins were characterized with respect to their affinities for PRODUCTION OF ANTHOCYANIN PIGMENT2 (PAP2), a R2R3-MYB which is induced by nitrogen depletion and is part of MBW complexes promoting anthocyanin synthesis. GL3 and EGL3 were also tested for their binding to MYBL2, a negative regulator of anthocyanin synthesis and MBW complexes. Using heterologously expressed proteins and Microscale Thermophoresis, GL3 showed binding constants (Kd) of 3.5±1.7 and 22.7±3.7 μM, whereas EGL3 showed binding constants of 7.5±2.3 and 8.9±1.4 μM for PAP2 and MYBL2, respectively. This implies that MYBL2 will not inhibit a MBW complex containing GL3 as easily as for a complex containing EGL3. In transgenic plants where EGL3 reaches high concentrations compared with MYBL2 the equilibrium is shifted and MYBL2 is not likely to be an efficient competitor, hence anthocyanin formation could be restored by either EGL3 or GL3 genes when overexpressed by help of the 35S promoter. The present work underpins that GL3 is essential for anthocyanin accumulation under nitrogen depletion not only due to transcriptional activation, but also because of binding properties to proteins promoting or inhibiting the activity of the MBW complex. PMID:25659750

  3. Anthocyanin Accumulation, Antioxidant Ability and Stability, and a Transcriptional Analysis of Anthocyanin Biosynthesis in Purple Heading Chinese Cabbage (Brassica rapa L. ssp. pekinensis).

    PubMed

    He, Qiong; Zhang, Zhanfeng; Zhang, Lugang

    2016-01-13

    Heading Chinese cabbage (Brassica rapa L. ssp. pekinensis) is a significant dietary vegetable for its edible heading leaves in Asia countries. The new purple anthocyanin-rich pure line (11S91) was successfully bred, and the anthocyanins were mainly distributed in 2-3 cell layers beneath the leaf epidermis, whereas siliques and stems accumulated only a cell layer of anthocyanins. The anthocyanins of 11S91 were more stable at pHs below 3.0 and temperatures below 45 °C. The total antioxidant ability was highly positive correlated with the anthocyanin content in 11S91. Thirty-two anthocyanins were separated and identified, and 70% of them were glycosylated and acylated cyanidins. The four major anthocyanins present were cyanidin-3-sophoroside(p-coumaroyl)-5-glucoside(malonyl), cyanidin-3-sophoroside(ferulyl)-5-glucoside(malonyl), cyanidin-3-sophoroside(sinapyl-p-coumaroyl)-5-glucoside(malonyl), and cyanidin-3-sophoroside-(sinapyl-ferulyl)-5-glucoside(malonyl). According to the expression of biosynthetic genes and the component profile of anthocyanins in 11S91 and its parents, regulatory genes BrMYB2 and BrTT8 probably activate the anthocyanin biosynthesis but other factors may govern the primary anthocyanins and the distribution. PMID:26709726

  4. Anthocyanin Accumulation, Antioxidant Ability and Stability, and a Transcriptional Analysis of Anthocyanin Biosynthesis in Purple Heading Chinese Cabbage (Brassica rapa L. ssp. pekinensis).

    PubMed

    He, Qiong; Zhang, Zhanfeng; Zhang, Lugang

    2016-01-13

    Heading Chinese cabbage (Brassica rapa L. ssp. pekinensis) is a significant dietary vegetable for its edible heading leaves in Asia countries. The new purple anthocyanin-rich pure line (11S91) was successfully bred, and the anthocyanins were mainly distributed in 2-3 cell layers beneath the leaf epidermis, whereas siliques and stems accumulated only a cell layer of anthocyanins. The anthocyanins of 11S91 were more stable at pHs below 3.0 and temperatures below 45 °C. The total antioxidant ability was highly positive correlated with the anthocyanin content in 11S91. Thirty-two anthocyanins were separated and identified, and 70% of them were glycosylated and acylated cyanidins. The four major anthocyanins present were cyanidin-3-sophoroside(p-coumaroyl)-5-glucoside(malonyl), cyanidin-3-sophoroside(ferulyl)-5-glucoside(malonyl), cyanidin-3-sophoroside(sinapyl-p-coumaroyl)-5-glucoside(malonyl), and cyanidin-3-sophoroside-(sinapyl-ferulyl)-5-glucoside(malonyl). According to the expression of biosynthetic genes and the component profile of anthocyanins in 11S91 and its parents, regulatory genes BrMYB2 and BrTT8 probably activate the anthocyanin biosynthesis but other factors may govern the primary anthocyanins and the distribution.

  5. Sp1 mediates repression of the resistin gene by PPAR{gamma} agonists in 3T3-L1 adipocytes

    SciTech Connect

    Chung, S.S.; Choi, H.H.; Cho, Y.M.; Lee, H.K.; Park, K.S. . E-mail: kspark@snu.ac.kr

    2006-09-15

    Resistin is an adipokine related to obesity and insulin resistance. Expression of the resistin gene is repressed by the treatment of peroxisome proliferator-activated receptor {gamma} (PPAR{gamma}) agonists, thiazolidinediones (TZDs). In this study, we investigated the mechanism by which TZDs inhibit the resistin gene expression. Resistin gene expression was decreased by TZD in fully differentiated 3T3-L1 adipocytes, which was abolished after treatment of cycloheximide (a protein synthesis inhibitor). TZD could not repress the expression of the resistin gene in the presence of mithramycin A (an Sp1 binding inhibitor). Sp1 binding site of the resistin promoter (-122/-114 bp) was necessary for the repression. Further investigation of the effect of TZDs on the modification of Sp1 showed that the level of O-glycosylation of Sp1 was decreased in this process. These results suggest that PPAR{gamma} activation represses the expression of the resistin gene by modulating Sp1 activity.

  6. Degradation kinetics of anthocyanin in blueberry juice during thermal treatment.

    PubMed

    Kechinski, Carolina Pereira; Guimarães, Pâmela Virgínia Ramos; Noreña, Caciano Pelayo Zapata; Tessaro, Isabel Cristina; Marczak, Lígia Damasceno Ferreira

    2010-03-01

    The kinetics of anthocyanin degradation in blueberry juice during thermal treatment at 40, 50, 60, 70, and 80 degrees C were investigated in the present study. Anthocyanin degradation was analyzed up to the level of 50% retention using a pH differential method. The degradation of anthocyanin at each temperature level followed a first-order kinetic model, and the values of half-life time (t(1/2)) at temperatures of 40, 50, 60, 70, and 80 degrees C were found to be 180.5, 42.3, 25.3, 8.6, and 5.1 h, respectively. The activation energy value of the degradation of the 8.9 degrees Brix blueberry juice during heating was 80.4 kJ.mol(-1). The thermodynamic functions of activation (DeltaG, DeltaH, and DeltaS) have been determined as central to understanding blueberry degradation. PMID:20492222

  7. Characterization of Escherichia coli Flagellar Mutants That are Insensitive to Catabolite Repression

    PubMed Central

    Silverman, Michael; Simon, Melvin

    1974-01-01

    In Escherichia coli, the synthesis of the flagellar organelle is sensitive to catabolite repression. Synthesis requires the presence of the cyclic adenosine monophosphate receptor protein (Crp) and 3′,5′-cyclic adenosine monophosphate (cAMP); i.e., mutants that lack Crp or adenylcyclase (Cya) synthesize no flagella. We isolated and characterized a series of mutants (cfs) that restored flagella-forming ability in a Crp strain of E. coli. The mutations in these strains were transferred onto episomes and they were then introduced into a variety of other strains. The presence of the mutation resulted in flagella synthesis in Cya and Crp strains as well as in the wild type grown under conditions of catabolite repression. Deletion analysis and other genetic studies indicated that: (i) the cfs mutations had a dominant effect when they were in the transconfiguration in merodiploids: (ii) they occurred in or very close to the flaI gene: and (iii) their expression required the presence of an intact flaI gene adjacent to the cfs mutation. Biochemical studies showed that the synthesis of at least two flagellar polypeptides, the hook subunit and an amber fragment of flagellin, were absent in strains that carried a cya mutation. Their synthesis was depressed in strains grown under conditions of catabolite repression. The presence of the cfs mutation restored the specific synthesis of these two polypeptides. We suggest that the formation of the flaI gene product is the step in flagellar synthesis that is catabolite sensitive and requires cAMP. We propose a regulatory function for the product of the flaI gene. Images PMID:4373438

  8. Conventional, ultrasound-assisted, and accelerated-solvent extractions of anthocyanins from purple sweet potatoes.

    PubMed

    Cai, Zhan; Qu, Ziqian; Lan, Yu; Zhao, Shujuan; Ma, Xiaohua; Wan, Qiang; Jing, Pu; Li, Pingfan

    2016-04-15

    Purple sweet potatoes (PSPs) are rich in anthocyanins. In this study, we investigated the extraction efficiency of anthocyanins from PSPs using conventional extraction (CE), ultrasound-assisted extraction (UAE), and accelerated-solvent extraction (ASE). Additionally, the effects of these extraction methods on antioxidant activity and anthocyanin composition of PSP extracts were evaluated. In order of decreasing extraction efficiency, the extraction methods were ASE>UAE>CE for anthocyanins (218-244 mg/100 g DW) and CE>UAE>ASE for total phenolics (631-955 mg/100 g DW) and flavonoids (28-40 mg/100 g DW). Antioxidant activities of PSP extracts were CE≈UAE>ASE for ORAC (766-1091 mg TE/100 g DW) and ASE>CE≈UAE for FRAP (1299-1705 mg TE/100 g DW). Twelve anthocyanins were identified. ASE extracts contained more diacyl anthocyanins and less nonacyl and monoacyl anthocyanins than CE and ASE extracts (P<0.05).

  9. Conventional, ultrasound-assisted, and accelerated-solvent extractions of anthocyanins from purple sweet potatoes.

    PubMed

    Cai, Zhan; Qu, Ziqian; Lan, Yu; Zhao, Shujuan; Ma, Xiaohua; Wan, Qiang; Jing, Pu; Li, Pingfan

    2016-04-15

    Purple sweet potatoes (PSPs) are rich in anthocyanins. In this study, we investigated the extraction efficiency of anthocyanins from PSPs using conventional extraction (CE), ultrasound-assisted extraction (UAE), and accelerated-solvent extraction (ASE). Additionally, the effects of these extraction methods on antioxidant activity and anthocyanin composition of PSP extracts were evaluated. In order of decreasing extraction efficiency, the extraction methods were ASE>UAE>CE for anthocyanins (218-244 mg/100 g DW) and CE>UAE>ASE for total phenolics (631-955 mg/100 g DW) and flavonoids (28-40 mg/100 g DW). Antioxidant activities of PSP extracts were CE≈UAE>ASE for ORAC (766-1091 mg TE/100 g DW) and ASE>CE≈UAE for FRAP (1299-1705 mg TE/100 g DW). Twelve anthocyanins were identified. ASE extracts contained more diacyl anthocyanins and less nonacyl and monoacyl anthocyanins than CE and ASE extracts (P<0.05). PMID:26616949

  10. Comparison of polyphenol, anthocyanin and antioxidant capacity in four varieties of Lonicera caerulea berry extracts.

    PubMed

    Wang, Yuehua; Zhu, Jinyan; Meng, Xianjun; Liu, Suwen; Mu, Jingjing; Ning, Chong

    2016-04-15

    Four varieties of Lonicera caerulea berries--'Wild', 'Beilei', 'No. 1', and 'No. 2'--were compared with respect to extraction yield, fruit weight, total soluble solids, polyphenol and anthocyanin contents, oxygen radical absorbance capacity (ORAC), and anthocyanin composition. Sixteen individual anthocyanins were identified in the selected varieties. Acylated anthocyanins, cyanidin 3-acetylhexoside and peonidin 3-acetylhexoside, were identified in L. caerulea berries for the first time. Cyanidin-3-glucoside was the most prominent anthocyanin in all four tested varieties. Wild type of L. caerulea fruit ('Wild'), with the highest polyphenol content, contained 14 anthocyanins and the highest ORAC value. Eleven anthocyanins were found in 'Beilei' berries, which had a higher ORAC value than 'No. 1' and 'No. 2'. The highest total soluble solid content and extraction yield were found in 'No. 2' and 'Wild' berries, respectively.

  11. Anthocyanin Accumulation and Molecular Analysis of Correlated Genes in Purple Kohlrabi (Brassica oleracea var. gongylodes L.).

    PubMed

    Zhang, Yanjie; Hu, Zongli; Zhu, Mingku; Zhu, Zhiguo; Wang, Zhijin; Tian, Shibing; Chen, Guoping

    2015-04-29

    Kohlrabi (Brassica oleracea var. gongylodes L.) is an important dietary vegetable cultivated and consumed widely for the round swollen stem. Purple kohlrabi shows abundant anthocyanin accumulation in the leaf and swollen stem. Here, different kinds of anthocyanins were separated and identified from the purple kohlrabi cultivar (Kolibri) by high-performance liquid chromatography-electrospray ionization tandem mass spectrometry. In order to study the molecular mechanism of anthocyanin biosynthesis in purple kohlrabi, the expression of anthocyanin biosynthetic genes and regulatory genes in purple kohlrabi and a green cultivar (Winner) was examined by quantitative PCR. In comparison with the colorless parts in the two cultivars, most of the anthocyanin biosynthetic genes and two transcription factors were drastically upregulated in the purple tissues. To study the effects of light shed on the anthocyanin accumulation of kohlrabi, total anthocyanin contents and transcripts of associated genes were analyzed in sprouts of both cultivars grown under light and dark conditions.

  12. The impact of red cabbage fermentation on bioavailability of anthocyanins and antioxidant capacity of human plasma.

    PubMed

    Wiczkowski, Wieslaw; Szawara-Nowak, Dorota; Romaszko, Jerzy

    2016-01-01

    The effect of red cabbage fermentation on anthocyanin bioavailability and plasma antioxidant capacity in humans was studied. In a randomized crossover study, 13 volunteers consumed fresh and fermented red cabbage. Blood and urine samples were collected before and after consumption. Analyses of anthocyanins by HPLC-MS/MS and plasma antioxidant capacity by photochemiluminescence assay were conducted. Red cabbage products contained 20 different nonacylated and acylated anthocyanins with the main structure of cyanidin triglucosides. The anthocyanins ingested were present in physiological fluids in form of 18 native anthocyanins and 12 metabolites (methylated, glucuronided, sulfated). Among cyanidin metabolites identified, methylated forms were predominant. Bioavailability of anthocyanin from fresh red cabbage was over 10% higher than from fermented red cabbage. Upon fresh cabbage consumption, volunteers plasma showed higher antioxidant capacity than after fermented cabbage intake. The study has shown that fermentation process affects red cabbage anthocyanins bioavailability and human plasma antioxidant capacity.

  13. Comparison of polyphenol, anthocyanin and antioxidant capacity in four varieties of Lonicera caerulea berry extracts.

    PubMed

    Wang, Yuehua; Zhu, Jinyan; Meng, Xianjun; Liu, Suwen; Mu, Jingjing; Ning, Chong

    2016-04-15

    Four varieties of Lonicera caerulea berries--'Wild', 'Beilei', 'No. 1', and 'No. 2'--were compared with respect to extraction yield, fruit weight, total soluble solids, polyphenol and anthocyanin contents, oxygen radical absorbance capacity (ORAC), and anthocyanin composition. Sixteen individual anthocyanins were identified in the selected varieties. Acylated anthocyanins, cyanidin 3-acetylhexoside and peonidin 3-acetylhexoside, were identified in L. caerulea berries for the first time. Cyanidin-3-glucoside was the most prominent anthocyanin in all four tested varieties. Wild type of L. caerulea fruit ('Wild'), with the highest polyphenol content, contained 14 anthocyanins and the highest ORAC value. Eleven anthocyanins were found in 'Beilei' berries, which had a higher ORAC value than 'No. 1' and 'No. 2'. The highest total soluble solid content and extraction yield were found in 'No. 2' and 'Wild' berries, respectively. PMID:26616984

  14. Red Anthocyanins and Yellow Carotenoids Form the Color of Orange-Flower Gentian (Gentiana lutea L. var. aurantiaca).

    PubMed

    Berman, Judit; Sheng, Yanmin; Gómez Gómez, Lourdes; Veiga, Tania; Ni, Xiuzhen; Farré, Gemma; Capell, Teresa; Guitián, Javier; Guitián, Pablo; Sandmann, Gerhard; Christou, Paul; Zhu, Changfu

    2016-01-01

    Flower color is an important characteristic that determines the commercial value of ornamental plants. Gentian flowers occur in a limited range of colors because this species is not widely cultivated as a cut flower. Gentiana lutea L. var. aurantiaca (abbr, aurantiaca) is characterized by its orange flowers, but the specific pigments responsible for this coloration are unknown. We therefore investigated the carotenoid and flavonoid composition of petals during flower development in the orange-flowered gentian variety of aurantiaca and the yellow-flowered variety of G. lutea L. var. lutea (abbr, lutea). We observed minor varietal differences in the concentration of carotenoids at the early and final stages, but only aurantiaca petals accumulated pelargonidin glycosides, whereas these compounds were not found in lutea petals. We cloned and sequenced the anthocyanin biosynthetic gene fragments from petals, and analyzed the expression of these genes in the petals of both varieties to determine the molecular mechanisms responsible for the differences in petal color. Comparisons of deduced amino acid sequences encoded by the isolated anthocyanin cDNA fragments indicated that chalcone synthase (CHS), chalcone isomerase (CHI), anthocyanidin synthase 1 (ANS1) and ANS2 are identical in both aurantiaca and lutea varieties whereas minor amino acid differences of the deduced flavonone 3-hydroxylase (F3H) and dihydroflavonol 4-reductase (DFR) between both varieties were observed. The aurantiaca petals expressed substantially higher levels of transcripts representing CHS, F3H, DFR, ANS and UDP-glucose:flavonoid-3-O-glucosyltransferase genes, compared to lutea petals. Pelargonidin glycoside synthesis in aurantiaca petals therefore appears to reflect the higher steady-state levels of pelargonidin synthesis transcripts. Moreover, possible changes in the substrate specificity of DFR enzymes may represent additional mechanisms for producing red pelargonidin glycosides in petals of

  15. Red Anthocyanins and Yellow Carotenoids Form the Color of Orange-Flower Gentian (Gentiana lutea L. var. aurantiaca).

    PubMed

    Berman, Judit; Sheng, Yanmin; Gómez Gómez, Lourdes; Veiga, Tania; Ni, Xiuzhen; Farré, Gemma; Capell, Teresa; Guitián, Javier; Guitián, Pablo; Sandmann, Gerhard; Christou, Paul; Zhu, Changfu

    2016-01-01

    Flower color is an important characteristic that determines the commercial value of ornamental plants. Gentian flowers occur in a limited range of colors because this species is not widely cultivated as a cut flower. Gentiana lutea L. var. aurantiaca (abbr, aurantiaca) is characterized by its orange flowers, but the specific pigments responsible for this coloration are unknown. We therefore investigated the carotenoid and flavonoid composition of petals during flower development in the orange-flowered gentian variety of aurantiaca and the yellow-flowered variety of G. lutea L. var. lutea (abbr, lutea). We observed minor varietal differences in the concentration of carotenoids at the early and final stages, but only aurantiaca petals accumulated pelargonidin glycosides, whereas these compounds were not found in lutea petals. We cloned and sequenced the anthocyanin biosynthetic gene fragments from petals, and analyzed the expression of these genes in the petals of both varieties to determine the molecular mechanisms responsible for the differences in petal color. Comparisons of deduced amino acid sequences encoded by the isolated anthocyanin cDNA fragments indicated that chalcone synthase (CHS), chalcone isomerase (CHI), anthocyanidin synthase 1 (ANS1) and ANS2 are identical in both aurantiaca and lutea varieties whereas minor amino acid differences of the deduced flavonone 3-hydroxylase (F3H) and dihydroflavonol 4-reductase (DFR) between both varieties were observed. The aurantiaca petals expressed substantially higher levels of transcripts representing CHS, F3H, DFR, ANS and UDP-glucose:flavonoid-3-O-glucosyltransferase genes, compared to lutea petals. Pelargonidin glycoside synthesis in aurantiaca petals therefore appears to reflect the higher steady-state levels of pelargonidin synthesis transcripts. Moreover, possible changes in the substrate specificity of DFR enzymes may represent additional mechanisms for producing red pelargonidin glycosides in petals of

  16. Red Anthocyanins and Yellow Carotenoids Form the Color of Orange-Flower Gentian (Gentiana lutea L. var. aurantiaca)

    PubMed Central

    Gómez Gómez, Lourdes; Veiga, Tania; Ni, Xiuzhen; Farré, Gemma; Capell, Teresa; Guitián, Javier; Guitián, Pablo; Sandmann, Gerhard; Christou, Paul

    2016-01-01

    Flower color is an important characteristic that determines the commercial value of ornamental plants. Gentian flowers occur in a limited range of colors because this species is not widely cultivated as a cut flower. Gentiana lutea L. var. aurantiaca (abbr, aurantiaca) is characterized by its orange flowers, but the specific pigments responsible for this coloration are unknown. We therefore investigated the carotenoid and flavonoid composition of petals during flower development in the orange-flowered gentian variety of aurantiaca and the yellow-flowered variety of G. lutea L. var. lutea (abbr, lutea). We observed minor varietal differences in the concentration of carotenoids at the early and final stages, but only aurantiaca petals accumulated pelargonidin glycosides, whereas these compounds were not found in lutea petals. We cloned and sequenced the anthocyanin biosynthetic gene fragments from petals, and analyzed the expression of these genes in the petals of both varieties to determine the molecular mechanisms responsible for the differences in petal color. Comparisons of deduced amino acid sequences encoded by the isolated anthocyanin cDNA fragments indicated that chalcone synthase (CHS), chalcone isomerase (CHI), anthocyanidin synthase 1 (ANS1) and ANS2 are identical in both aurantiaca and lutea varieties whereas minor amino acid differences of the deduced flavonone 3-hydroxylase (F3H) and dihydroflavonol 4-reductase (DFR) between both varieties were observed. The aurantiaca petals expressed substantially higher levels of transcripts representing CHS, F3H, DFR, ANS and UDP-glucose:flavonoid-3-O-glucosyltransferase genes, compared to lutea petals. Pelargonidin glycoside synthesis in aurantiaca petals therefore appears to reflect the higher steady-state levels of pelargonidin synthesis transcripts. Moreover, possible changes in the substrate specificity of DFR enzymes may represent additional mechanisms for producing red pelargonidin glycosides in petals of

  17. Characterization of the cis elements in the proximal promoter regions of the anthocyanin pathway genes reveals a common regulatory logic that governs pathway regulation

    PubMed Central

    Zhu, Zhixin; Wang, Hailong; Wang, Yiting; Guan, Shan; Wang, Fang; Tang, Jingyu; Zhang, Ruijuan; Xie, Lulu; Lu, Yingqing

    2015-01-01

    Cellular activities such as compound synthesis often require the transcriptional activation of an entire pathway; however, the molecular mechanisms underlying pathway activation have rarely been explained. Here, the cis regulatory architecture of the anthocyanin pathway genes targeted by the transcription factor (TF) complex including MYB, bHLH, and WDR was systematically analysed in one species and the findings extended to others. In Ipomoea purpurea, the IpMYB1-IpbHLH2-IpWDR1 (IpMBW) complex was found to be orthologous to the PAP1-GL3-TTG1 (AtPGT) complex of Arabidopsis thaliana, and interacted with a 7-bp MYB-recognizing element (MRE) and a 6-bp bHLH-recognizing element (BRE) at the proximal promoter region of the pathway genes. There was little transcription of the gene in the absence of the MRE or BRE. The cis elements identified experimentally converged on two syntaxes, ANCNNCC for MREs and CACN(A/C/T)(G/T) for BREs, and our bioinformatic analysis showed that these were present within anthocyanin gene promoters in at least 35 species, including both gymnosperms and angiosperms. For the anthocyanin pathway, IpMBW and AtPGT recognized the interspecific promoters of both early and later genes. In A. thaliana, the seed-specific TF complex (TT2, TT8, and TTG1) may regulate all the anthocyanin pathway genes, in addition to the proanthocyanidin-specific BAN. When multiple TF complexes in the anthocyanin pathway were compared, the cis architecture played a role larger than the TF complex in determining the variation in promoter activity. Collectively, a cis logic common to the pathway gene promoters was found, and this logic is essential for the trans factors to regulate the pathway. PMID:25911741

  18. Long-term in vitro culture of grape berries and its application to assess the effects of sugar supply on anthocyanin accumulation.

    PubMed

    Dai, Zhan Wu; Meddar, Messaoud; Renaud, Christel; Merlin, Isabelle; Hilbert, Ghislaine; Delrot, Serge; Gomès, Eric

    2014-08-01

    Grape berry development and ripening are under complex regulation by the nutrients, hormones, and environment cues sensed by the berry. However, the biochemical and molecular mechanisms underlying these types of regulation are poorly understood. A simplified but realistic model system that enables fruit growth conditions to be modulated easily will facilitate the deciphering of these mechanisms. Here, an in vitro culture system of intact detached grape berries was developed by coupling the production of greenhouse fruiting-cuttings and in vitro organ culture techniques. (13)C and (15)N labelling experiments showed that this system enables the intact detached berries actively to absorb and utilize carbon and nitrogen from the culture medium. It was further used to study the effects of sugars on anthocyanin accumulation. A sucrose concentration >2% could induce anthocyanin synthesis in the absence of additional exogenous abscisic acid. The higher the sucrose concentration, the earlier was the induction of anthocyanin accumulation. Glucose, fructose, and sucrose increased anthocyanin accumulation, with glucose and fructose being more effective than sucrose. This increase was not due to an increase in its precursor level, since the phenylalanine content was decreased by a high sugar supply. Instead, genome-wide transcriptome analysis suggests that the sugar-induced enhancement of anthocyanin accumulation results from altered expression of regulatory and structural genes (especially UDP-glucose:anthocyanidin 3-O-glucosyltransferase), together with massive reprogramming in signalling transduction pathways. This in vitro system may serve to study the response of berry composition to nutrient factors and hormones, and their interaction with environmental factors (e.g. light and temperature), which can all be finely tuned and controlled.

  19. Long-term in vitro culture of grape berries and its application to assess the effects of sugar supply on anthocyanin accumulation.

    PubMed

    Dai, Zhan Wu; Meddar, Messaoud; Renaud, Christel; Merlin, Isabelle; Hilbert, Ghislaine; Delrot, Serge; Gomès, Eric

    2014-08-01

    Grape berry development and ripening are under complex regulation by the nutrients, hormones, and environment cues sensed by the berry. However, the biochemical and molecular mechanisms underlying these types of regulation are poorly understood. A simplified but realistic model system that enables fruit growth conditions to be modulated easily will facilitate the deciphering of these mechanisms. Here, an in vitro culture system of intact detached grape berries was developed by coupling the production of greenhouse fruiting-cuttings and in vitro organ culture techniques. (13)C and (15)N labelling experiments showed that this system enables the intact detached berries actively to absorb and utilize carbon and nitrogen from the culture medium. It was further used to study the effects of sugars on anthocyanin accumulation. A sucrose concentration >2% could induce anthocyanin synthesis in the absence of additional exogenous abscisic acid. The higher the sucrose concentration, the earlier was the induction of anthocyanin accumulation. Glucose, fructose, and sucrose increased anthocyanin accumulation, with glucose and fructose being more effective than sucrose. This increase was not due to an increase in its precursor level, since the phenylalanine content was decreased by a high sugar supply. Instead, genome-wide transcriptome analysis suggests that the sugar-induced enhancement of anthocyanin accumulation results from altered expression of regulatory and structural genes (especially UDP-glucose:anthocyanidin 3-O-glucosyltransferase), together with massive reprogramming in signalling transduction pathways. This in vitro system may serve to study the response of berry composition to nutrient factors and hormones, and their interaction with environmental factors (e.g. light and temperature), which can all be finely tuned and controlled. PMID:24477640

  20. Long-term in vitro culture of grape berries and its application to assess the effects of sugar supply on anthocyanin accumulation

    PubMed Central

    Dai, Zhan Wu; Meddar, Messaoud; Renaud, Christel; Merlin, Isabelle; Hilbert, Ghislaine; Delrot, Serge; Gomès, Eric

    2014-01-01

    Grape berry development and ripening are under complex regulation by the nutrients, hormones, and environment cues sensed by the berry. However, the biochemical and molecular mechanisms underlying these types of regulation are poorly understood. A simplified but realistic model system that enables fruit growth conditions to be modulated easily will facilitate the deciphering of these mechanisms. Here, an in vitro culture system of intact detached grape berries was developed by coupling the production of greenhouse fruiting-cuttings and in vitro organ culture techniques. 13C and 15N labelling experiments showed that this system enables the intact detached berries actively to absorb and utilize carbon and nitrogen from the culture medium. It was further used to study the effects of sugars on anthocyanin accumulation. A sucrose concentration >2% could induce anthocyanin synthesis in the absence of additional exogenous abscisic acid. The higher the sucrose concentration, the earlier was the induction of anthocyanin accumulation. Glucose, fructose, and sucrose increased anthocyanin accumulation, with glucose and fructose being more effective than sucrose. This increase was not due to an increase in its precursor level, since the phenylalanine content was decreased by a high sugar supply. Instead, genome-wide transcriptome analysis suggests that the sugar-induced enhancement of anthocyanin accumulation results from altered expression of regulatory and structural genes (especially UDP-glucose:anthocyanidin 3-O-glucosyltransferase), together with massive reprogramming in signalling transduction pathways. This in vitro system may serve to study the response of berry composition to nutrient factors and hormones, and their interaction with environmental factors (e.g. light and temperature), which can all be finely tuned and controlled. PMID:24477640

  1. Liking of anthocyanin-rich juices by children and adolescents.

    PubMed

    Drossard, Claudia; Fröhling, Bettina; Bolzenius, Katja; Dietrich, Helmut; Kunz, Clemens; Kersting, Mathilde

    2012-04-01

    There is evidence that a diet rich in plant foods is protective against cardiovascular disease and cancer, partly attributable to secondary plant metabolites such as anthocyanins, a colourful group of flavonoids. As at present children and adolescents do not consume the recommended amounts of fruits and vegetables, one possible way of increasing intake, and particularly intake of anthocyanins, may be an anthocyanin-rich juice, since fruit juice is popular with young Germans. We produced eight different fruit products (six juices, two smoothies), and conducted hedonic tests with participants from the DONALD Study. Paired comparisons showed that most subjects preferred apple to apple-bilberry juice, but grape vs. grape-bilberry juice was liked equally frequently. Rated on a hedonic scale the grape-bilberry mixture was preferred to apple-bilberry, both as juice and as smoothie. With regard to viscosity, juices were preferred to smoothies, both as grape-bilberry and as apple-bilberry. Internal Preference Mapping revealed however consumer subgroups with different preferences, raising the question which product should be promoted in order to reach a large target group. The product richest in anthocyanins, grape-bilberry juice, was accepted very well and may therefore be suitable for promotion to children, although the high sugar content of this juice must be taken into account.

  2. Characterization of anthocyanins in blueberries using LC/MS/MS

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Anthocyanins consist of a 2-phenylbenzopyrylium moiety with a variety of polyhydroxyl, polymethoxyl, and glycosolated substituents. Their presence is responsible for the red to purplish colors associated with fresh fruits and berries. There is currently a strong interest in these compounds because...

  3. Comparison of minor anthocyanins in different varieties of blueberries

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Anthocyanins consist of a 2-phenylbenzopyrylium moiety with a variety of polyhydroxyl, polymethoxyl, and glycosolated substituents. Their presence is responsible for the red to purplish colors associated with fresh fruits and berries. There is currently a strong interest in these compounds because...

  4. The great repression: chromatin and cryptic transcription.

    PubMed

    Hennig, Bianca P; Fischer, Tamás

    2013-01-01

    The eukaryotic chromatin structure is essential in correctly defining transcription units. Impairing this structure can activate cryptic promoters, and lead to the accumulation of aberrant RNA transcripts. Here we discuss critical pathways that are responsible for the repression of cryptic transcription and the maintenance of genome integrity.

  5. BZLF1 governs CpG-methylated chromatin of Epstein-Barr Virus reversing epigenetic repression.

    PubMed

    Woellmer, Anne; Arteaga-Salas, Jose M; Hammerschmidt, Wolfgang

    2012-09-01

    Epigenetic mechanisms are essential for the regulation of all genes in mammalian cells but transcriptional repression including DNA methylation are also major epigenetic mechanisms of defense inactivating potentially harmful pathogens. Epstein-Barr Virus (EBV), however, has evolved to take advantage of CpG methylated DNA to regulate its own biphasic life cycle. We show here that latent EBV DNA has an extreme composition of methylated CpG dinucleotides with a bimodal distribution of unmethylated or fully methylated DNA at active latent genes or completely repressed lytic promoters, respectively. We find this scenario confirmed in primary EBV-infected memory B cells in vivo. Extensive CpG methylation of EBV's DNA argues for a very restricted gene expression during latency. Above-average nucleosomal occupancy, repressive histone marks, and Polycomb-mediated epigenetic silencing further shield early lytic promoters from activation during latency. The very tight repression of viral lytic genes must be overcome when latent EBV enters its lytic phase and supports de novo virus synthesis in infected cells. The EBV-encoded and AP-1 related transcription factor BZLF1 overturns latency and initiates virus synthesis in latently infected cells. Paradoxically, BZLF1 preferentially binds to CpG-methylated motifs in key viral promoters for their activation. Upon BZLF1 binding, we find nucleosomes removed, Polycomb repression lost, and RNA polymerase II recruited to the activated early promoters promoting efficient lytic viral gene expression. Surprisingly, DNA methylation is maintained throughout this phase of viral reactivation and is no hindrance to active transcription of extensively CpG methylated viral genes as thought previously. Thus, we identify BZLF1 as a pioneer factor that reverses epigenetic silencing of viral DNA to allow escape from latency and report on a new paradigm of gene regulation. PMID:22969425

  6. Foliar anthocyanin content - Sensitivity of vegetation indices using green reflectance

    NASA Astrophysics Data System (ADS)

    Vina, A.; Gitelson, A. A.

    2009-12-01

    The amount and composition of photosynthetic and non-photosynthetic foliar pigments varies primarily as a function of species, developmental and phenological stages, and environmental stresses. Information on the absolute and relative amounts of these pigments thus provides insights onto the physiological conditions of plants and their responses to stress, and has the potential to be used for evaluating plant species composition and diversity across broad geographic regions. Anthocyanins in particular, are non-photosynthetic pigments associated with the resistance of plants to environmental stresses (e.g., drought, low soil nutrients, high radiation, herbivores, and pathogens). As they absorb radiation primarily in the green region of the electromagnetic spectrum (around 540-560 nm), broad-band vegetation indices that use this region in their formulation will respond to their presence. We evaluated the sensitivity of three vegetation indices using reflectance in the green spectral region (the green Normalized Difference Vegetation Index, gNDVI, the green Chlorophyll Index, CIg, and the Visible Atmospherically Resistant Vegetation Index, VARI) to foliar anthocyanins in five different species. For comparison purposes the widely used Normalized Difference Vegetation Index, NDVI was also evaluated. Among the four indices tested, the VARI, which uses only spectral bands in the visible region of the electromagnetic spectrum, was found to be inversely and linearly related to the relative amount of foliar anthocyanins. While this result was obtained at leaf level, it opens new possibilities for analyzing anthocyanin content across multiple scales, by means of currently operational aircraft- and spacecraft-mounted broad-band sensor systems. Further studies that evaluate the sensitivity of the VARI to the relative content of anthocyanins across space (e.g., at canopy and regional scales) and time, and its relationship with plant biodiversity and vegetation stresses, are

  7. [Correlation between the synthesis of extracellular proteases and the synthesis of the red pigment prodigiosin in Serratia marcescens].

    PubMed

    Loriia, Zh K; Briukner, B; Egorov, N S

    1977-01-01

    A correlation has been established between synthesis of exocellular protease and synthesis of a red pigment prodigiosine by Serratia marcescens. Chloramphenicol, an inhibitor of protein synthesis, inhibits also synthesis of the pigment. Leucine, an inductor of synthesis of the exocellular protease by Serratia marcescens VI, induces also synthesis of the pigment. A mixture of 18 natural amino acids, asparagine and ammonium ions represses both synthesis of the enzyme and the pigment.

  8. Molecular characterization of an anthocyanin-related glutathione S-transferase gene in cyclamen.

    PubMed

    Kitamura, Satoshi; Akita, Yusuke; Ishizaka, Hiroshi; Narumi, Issay; Tanaka, Atsushi

    2012-04-15

    Anthocyanins are a subclass of flavonoids and are a major contributor to flower colors ranging from red to blue and purple. Previous studies in model and ornamental plants indicate a member of the glutathione S-transferase (GST) gene family is involved in vacuolar accumulation of anthocyanins. In order to identify the anthocyanin-related GST in cyclamen, degenerate PCR was performed using total RNA from immature young petals. Four candidates of GSTs (CkmGST1 to CkmGST4) were isolated. Phylogenetic analysis indicated that CkmGST3 was closely related to PhAN9, an anthocyanin-related GST of petunia, and this clade was clustered with other known anthocyanin-related GSTs. Expression analysis at different developmental stages of petals revealed that CkmGST3 was strongly expressed in paler pigmented petals than in fully pigmented petals, in contrast to the constitutive expression of the other three candidates during petal development. This expression pattern of CkmGST3 was correlated with those of other anthocyanin biosynthetic genes such as CkmF3'5'H and CkmDFR2. Molecular complementation of Arabidopsis tt19, a knockout mutant of an anthocyanin-related GST gene, demonstrated that CkmGST3 could complement the anthocyanin-less phenotype of tt19. Transgenic plants that expressed the other three CkmGSTs did not show anthocyanin accumulation. These results indicate CkmGST3 functions in anthocyanin accumulation in cyclamen.

  9. Coordination of anthocyanin decline and photosynthetic maturation in juvenile leaves of three deciduous tree species.

    PubMed

    Hughes, Nicole M; Morley, Christianna B; Smith, William K

    2007-01-01

    Juvenile leaves in high-light environments commonly appear red as a result of anthocyanin pigments, which play a photoprotective role during light-sensitive ontogenetic stages. The loss of anthocyanin during leaf development presumably corresponds to a decreased need for photoprotection, as photosynthetic maturation allows leaves to utilize higher light intensities. However, the relationship between photosynthetic development and anthocyanin decline has yet to be quantitatively described. In this study, anthocyanin concentration was measured against photopigment content, lamina thickness, anatomical development, and photosynthetic CO(2) exchange in developing leaves of three deciduous tree species. In all species, anthocyanin disappearance corresponded with development of c. 50% mature photopigment concentrations, c. 80% lamina thickness, and differentiation of the mesophyll into palisade and spongy layers. Photosynthetic gas exchange correlated positively with leaf thickness and chlorophyll content, and negatively with anthocyanin concentration. Species with more rapid photosynthetic maturation lost anthocyanin earliest in development. Chlorophyll a/b ratios increased with leaf age, and were lower than those of acyanic species, consistent with a shading effect of anthocyanin. These results suggest that anthocyanin reassimilation is linked closely with chloroplast and whole-leaf developmental processes, supporting the idea that anthocyanins protect tissues until light processing and carbon fixation have matured to balance energy capture with utilization.

  10. Repression of the albumin gene in Novikoff hepatoma cells

    SciTech Connect

    Capetanaki, Y.G.; Flytzanis, C.N.; Alonso, A.

    1982-03-01

    Novikoff hepatoma cells have lost their capacity to synthesize albumin. As a first approach to study the mechanisms underlying this event, in vitro translation in a reticulocyte system was performed using total polyadenylated mRNA from rat liver and Novikoff hepatoma cells. Immunoprecipitation of the in vitro translation products with albumin-specific antibody revealed a total lack of albumin synthesis in Novikoff hepatoma, suggesting the absence of functional albumin mRNA in these cells. Titration experiments using as probe albumin cDNA cloned in pBR322 plasmid demonstrated the absence of albumin-specific sequences in both polysomal and nuclear polyadenylated and total RNA from Novikoff cells. This albumin recombinant plasmid was obtained by screening a rat liver cDNA library with albumin (/sup 32/P)cDNA reverse transcribed from immuno-precipitated mRNA. The presence of an albumin-specific gene insert was documented with translation assays as well as by restriction mapping. Repression of the albumin gene at the transcriptional level was further demonstrated by RNA blotting experiments using the cloned albumin cDNA probe. Genomic DNA blots using the cloned albumin cDNA as probe did not reveal any large-scale deletions, insertions, or rearrangements in the albumin gene, suggesting that the processes involved in the suppression of albumin mRNA synthesis do not involve extensive genomic rearrangements.

  11. The natural product peiminine represses colorectal carcinoma tumor growth by inducing autophagic cell death

    SciTech Connect

    Lyu, Qing; Tou, Fangfang; Su, Hong; Wu, Xiaoyong; Chen, Xinyi; Zheng, Zhi

    2015-06-19

    Autophagy is evolutionarily conservative in eukaryotic cells that engulf cellular long-lived proteins and organelles, and it degrades the contents through fusion with lysosomes, via which the cell acquires recycled building blocks for the synthesis of new molecules. In this study, we revealed that peiminine induces cell death and enhances autophagic flux in colorectal carcinoma HCT-116 cells. We determined that peiminine enhances the autophagic flux by repressing the phosphorylation of mTOR through inhibiting upstream signals. Knocking down ATG5 greatly reduced the peiminine-induced cell death in wild-type HCT-116 cells, while treating Bax/Bak-deficient cells with peiminine resulted in significant cell death. In summary, our discoveries demonstrated that peiminine represses colorectal carcinoma cell proliferation and cell growth by inducing autophagic cell death. - Highlights: • Peiminine induces autophagy and upregulates autophagic flux. • Peiminine represses colorectal carcinoma tumor growth. • Peiminine induces autophagic cell death. • Peiminine represses mTOR phosphorylation by influencing PI3K/Akt and AMPK pathway.

  12. Pluripotency factors and Polycomb Group proteins repress aryl hydrocarbon receptor expression in murine embryonic stem cells.

    PubMed

    Ko, Chia-I; Wang, Qin; Fan, Yunxia; Xia, Ying; Puga, Alvaro

    2014-01-01

    The aryl hydrocarbon receptor (AHR) is a transcription factor and environmental sensor that regulates expression of genes involved in drug-metabolism and cell cycle regulation. Chromatin immunoprecipitation analyses, Ahr ablation in mice and studies with orthologous genes in invertebrates suggest that AHR may also play a significant role in embryonic development. To address this hypothesis, we studied the regulation of Ahr expression in mouse embryonic stem cells and their differentiated progeny. In ES cells, interactions between OCT3/4, NANOG, SOX2 and Polycomb Group proteins at the Ahr promoter repress AHR expression, which can also be repressed by ectopic expression of reprogramming factors in hepatoma cells. In ES cells, unproductive RNA polymerase II binds at the Ahr transcription start site and drives the synthesis of short abortive transcripts. Activation of Ahr expression during differentiation follows from reversal of repressive marks in Ahr promoter chromatin, release of pluripotency factors and PcG proteins, binding of Sp factors, establishment of histone marks of open chromatin, and engagement of active RNAPII to drive full-length RNA transcript elongation. Our results suggest that reversible Ahr repression in ES cells holds the gene poised for expression and allows for a quick switch to activation during embryonic development.

  13. Effect of cultivar on phenolic levels, anthocyanin composition, and antioxidant properties in purple basil (Ocimum basilicum L.).

    PubMed

    Flanigan, Patrick M; Niemeyer, Emily D

    2014-12-01

    In this study, we determined the effect of cultivar on total and individual anthocyanin concentrations and phenolic acid levels in eight purple basil varieties and examined the relationship between anthocyanin content, phenolic acid composition, and antioxidant properties. Cultivar had a significant influence on total anthocyanin concentrations as well as individual anthocyanin composition. The four major basil anthocyanins (labelled A-D) were quantified and cultivar had a statistically significant effect on anthocyanins B (p<0.01), C (p<0.01), and D (p<0.01), but not on anthocyanin A (p=0.94). Cultivar did not have a significant effect on total phenolic levels, although it did influence the concentration of some individual phenolic acids, including caftaric (p=0.03) and chicoric (p=0.04) acids. Although total phenolic and anthocyanin levels correlated with measured FRAP antioxidant capacities, for some cultivars the individual phenolic acid and anthocyanin composition was also an important factor affecting the antioxidant properties.

  14. Resveratrol-Mediated Repression and Reversion of Prostatic Myofibroblast Phenoconversion

    PubMed Central

    Gharaee-Kermani, Mehrnaz; Moore, Bethany B.; Macoska, Jill A.

    2016-01-01

    Background Resveratrol, a phytoalexin found in berries, peanuts, grapes, and red wine, inhibits oxidation, inflammation, and cell proliferation and collagen synthesis in multiple cell types and or animal models. It represses collagen deposition in the vasculature, heart, lung, kidney, liver, and esophagus in animal models and may have some utility as an anti-fibrotic. Recent studies have shown that increased collagen deposition and tissue stiffness in the peri-urethral area of the prostate are associated with lower urinary tract dysfunction (LUTD) and urinary obstructive symptoms. The aim of this study was to determine whether Resveratrol might be useful to inhibit or revert TGFβ- and/or CXCL12-mediated myofibroblast phenoconversion of prostate fibroblasts in vitro, and therefore whether the use of anti-fibrotic therapeutics might be efficacious for the treatment of LUTD. Methods Primary prostate and lung tissues were explanted and fibroblast monolayers expanded in vitro. Primary and N1 immortalized prostate stromal fibroblasts, as well as primary fibroblasts cultured from a normal lung and one affected by idiopathic pulmonary fibrosis (IPF) for comparison, were grown in serum–free defined media supplemented with vehicle, TGFβ or CXCL12, pre- or post-treatment with Resveratrol, and were evaluated using immunofluorescence for alpha smooth muscle actin (αSMA) and collagen I (COL1) protein expression and assessed for cell proliferation, apoptosis, and COL1 and EGR1 transcript expression. Results This study showed that low concentrations of Resveratrol (≤50 μM) had no effect on N1 or primary prostate fibroblast cell proliferation, apoptosis, or COL1 or EGR1 gene transcription but repressed and reversed myofibroblast phenoconversion. As expected, these same effects were observed for IPF lung fibroblasts though higher levels of Resveratrol (≥100uM) were required. Taken together, these data suggest that, like lung fibroblasts, prostate fibroblast to

  15. Anthocyanin copigmentation and color of wine: The effect of naturally obtained hydroxycinnamic acids as cofactors.

    PubMed

    Bimpilas, Andreas; Panagopoulou, Marilena; Tsimogiannis, Dimitrios; Oreopoulou, Vassiliki

    2016-04-15

    Copigmentation of anthocyanins accounts for over 30% of fresh red wine color, while during storage, the color of polymeric pigments formed between anthocyanins and proanthocyanidins predominates. Rosmarinic acid and natural extracts rich in hydroxycinnamic acids, obtained from aromatic plants (Origanum vulgare and Satureja thymbra), were examined as cofactors to fresh Merlot wine and the effect on anthocyanin copigmentation and wine color was studied during storage for 6months. An increase of the copigmented anthocyanins that enhanced color intensity by 15-50% was observed, confirming the ability of complex hydroxycinnamates to form copigments. The samples with added cofactors retained higher percentages of copigmented anthocyanins and higher color intensity, compared to the control wine, up to 3 months. However, the change in the equilibrium between monomeric and copigmented anthocyanins that was induced by added cofactors, did not affect the rate of polymerization reactions during storage.

  16. The protective effect of blueberry anthocyanins against perfluorooctanoic acid-induced disturbance in planarian (Dugesia japonica).

    PubMed

    Yuan, Zuoqing; Zhang, Jianyong; Tu, Changchao; Wang, Zhijing; Xin, Wenpeng

    2016-05-01

    The influence of blueberry anthocyanins on perfluorooctanoic acid (PFOA)-induced stress response in planarian mitochondria was investigated. PFOA at 15mg/L and anthocyanins at 10 or 20mg/L were individually and simultaneously administered to planarians for up to 10d. The results showed PFOA treatment induced an increase in mitochondrial permeability transition pore opening and a decrease antioxidant capacity and enzyme activities. In anthocyanin treated animals, the activity of succinate dehydrogenase, cytochrome oxidase and monoamine oxidase increased, but mitochondrial permeability transition pore opening decreased and total antioxidant capacity increased. An improvement in above-mentioned physiological and biochemical parameters was found in the combined PFOA and anthocyanin treated animals, in a dose-dependent manner. Anthocyanins attenuated the PFOA induced toxicity; antioxidant capacity and enzyme activities are involved in the protective mechanism of anthocyanins. PMID:26836138

  17. Anthocyanins present in selected tropical fruits: acerola, jambolão, jussara, and guajiru.

    PubMed

    de Brito, Edy Sousa; de Araújo, Manuela Cristina Pessanha; Alves, Ricardo Elesbão; Carkeet, Colleen; Clevidence, Beverly A; Novotny, Janet A

    2007-11-14

    Many tropical fruits are rich in anthocyanins, though limited information is available about the characterization and quantification of these anthocyanins. The identification and quantification of anthocyanin pigments in four tropical fruits were determined by HPLC-MS/MS. Fruits studied included acerola (Malphigia emarginata), jussara (Euterpe edulis), jambolão (Syzygium cumini), and guajiru (Chrysobalanus icaco). All four fruits were found to contain anthocyanin pigments. Anthocyanidin backbones included cyanidin, delphinidin, peonidin, pelargonidin, petunidin, and malvidin. Guajiru contained several acylated forms, while acerola, jussara, and jambolão contained only nonacylated glycosides. These results demonstrate that these tropical fruits are rich in anthocyanins and that the anthocyanins are widely ranging in anthocyanidin backbone, glycosylation, and acylation.

  18. Anthocyanins: Model Compounds for Learning about More than pH

    NASA Astrophysics Data System (ADS)

    Curtright, Robert; Rynearson, James A.; Markwell, John

    1996-04-01

    We have all experienced anthocyanins as a part of the natural beauty of the plant world. Anthocyanins provide a startling contrast to an otherwise green world producing the beauty of garden-variety flowers, wildflowers, and the blazing colors of many trees, bushes, and berries. We believe that anthocyanins deserve a more prominent role as models for engaging student interest in basic chemical principles. In recent years it has become common to use anthocyanins as pH indicators. We believe that chemistry teachers can capitalize further on the natural interest of students in anthocyanin pigments to design meaningful lessons involving chromatography and hydrolysis. This article focuses on the use of anthocyanins in chromatography and hydrolysis.

  19. Anthocyanin copigmentation and color of wine: The effect of naturally obtained hydroxycinnamic acids as cofactors.

    PubMed

    Bimpilas, Andreas; Panagopoulou, Marilena; Tsimogiannis, Dimitrios; Oreopoulou, Vassiliki

    2016-04-15

    Copigmentation of anthocyanins accounts for over 30% of fresh red wine color, while during storage, the color of polymeric pigments formed between anthocyanins and proanthocyanidins predominates. Rosmarinic acid and natural extracts rich in hydroxycinnamic acids, obtained from aromatic plants (Origanum vulgare and Satureja thymbra), were examined as cofactors to fresh Merlot wine and the effect on anthocyanin copigmentation and wine color was studied during storage for 6months. An increase of the copigmented anthocyanins that enhanced color intensity by 15-50% was observed, confirming the ability of complex hydroxycinnamates to form copigments. The samples with added cofactors retained higher percentages of copigmented anthocyanins and higher color intensity, compared to the control wine, up to 3 months. However, the change in the equilibrium between monomeric and copigmented anthocyanins that was induced by added cofactors, did not affect the rate of polymerization reactions during storage. PMID:26616922

  20. Nuclear AXIN2 represses MYC gene expression

    SciTech Connect

    Rennoll, Sherri A.; Konsavage, Wesley M.; Yochum, Gregory S.

    2014-01-03

    Highlights: •AXIN2 localizes to cytoplasmic and nuclear compartments in colorectal cancer cells. •Nuclear AXIN2 represses the activity of Wnt-responsive luciferase reporters. •β-Catenin bridges AXIN2 to TCF transcription factors. •AXIN2 binds the MYC promoter and represses MYC gene expression. -- Abstract: The β-catenin transcriptional coactivator is the key mediator of the canonical Wnt signaling pathway. In the absence of Wnt, β-catenin associates with a cytosolic and multi-protein destruction complex where it is phosphorylated and targeted for proteasomal degradation. In the presence of Wnt, the destruction complex is inactivated and β-catenin translocates into the nucleus. In the nucleus, β-catenin binds T-cell factor (TCF) transcription factors to activate expression of c-MYC (MYC) and Axis inhibition protein 2 (AXIN2). AXIN2 is a member of the destruction complex and, thus, serves in a negative feedback loop to control Wnt/β-catenin signaling. AXIN2 is also present in the nucleus, but its function within this compartment is unknown. Here, we demonstrate that AXIN2 localizes to the nuclei of epithelial cells within normal and colonic tumor tissues as well as colorectal cancer cell lines. In the nucleus, AXIN2 represses expression of Wnt/β-catenin-responsive luciferase reporters and forms a complex with β-catenin and TCF. We demonstrate that AXIN2 co-occupies β-catenin/TCF complexes at the MYC promoter region. When constitutively localized to the nucleus, AXIN2 alters the chromatin structure at the MYC promoter and directly represses MYC gene expression. These findings suggest that nuclear AXIN2 functions as a rheostat to control MYC expression in response to Wnt/β-catenin signaling.

  1. Transthyretin represses neovascularization in diabetic retinopathy

    PubMed Central

    Shao, Jun

    2016-01-01

    Purpose The apoptosis of human umbilical vein endothelial cells has been reportedly induced by the protein transthyretin (TTR). In human ocular tissue, TTR is generally considered to be secreted mainly by retinal pigment epithelial cells (hRPECs); however, whether TTR affects the development of neovascularization in diabetic retinopathy (DR) remains unclear. Methods Natural and simulated DR media were used to culture human retinal microvascular endothelial cells (hRECs). Hyperglycemia was simulated by increasing the glucose concentration from 5.5 mM up to 25 mM, while hypoxia was induced with 200 µM CoCl2. To understand the effects of TTR on hRECs, cell proliferation was investigated under natural and DR conditions. Overexpression of TTR, an in vitro wound-healing assay, and a tube formation assay were employed to study the repression of TTR on hRECs. Real-time fluorescence quantitative PCR (qRT-PCR) was used to study the mRNA levels of DR-related genes, such as Tie2, VEGFR1, VEGFR2, Angpt1, and Angpt2. Results The proliferation of hRECs was significantly decreased in the simulated hyperglycemic and hypoxic DR environments. The cells were further repressed by added exogenous or endogenous TTR only under hyperglycemic conditions. The in vitro migration and tube formation processes of the hRECs were inhibited with TTR; furthermore, in the hyperglycemia and hyperglycemia/hypoxia environments, the levels of Tie2 and Angpt1 mRNA were enhanced with exogenous TTR, while those of VEGFR1, VEGFR2, and Angpt1 were repressed. Conclusions In hyperglycemia, the proliferation, migration, and neovascularization of hRECs were significantly inhibited by TTR. The key genes for DR neovascularization, including Tie2, VEGFR1, VEGFR2, Angpt1, and Angpt2, were regulated by TTR. Under DR conditions, TTR significantly represses neovascularization by inhibiting the proliferation, migration and tube formation of hRECs. PMID:27746673

  2. Memory repression: brain mechanisms underlying dissociative amnesia.

    PubMed

    Kikuchi, Hirokazu; Fujii, Toshikatsu; Abe, Nobuhito; Suzuki, Maki; Takagi, Masahito; Mugikura, Shunji; Takahashi, Shoki; Mori, Etsuro

    2010-03-01

    Dissociative amnesia usually follows a stressful event and cannot be attributable to explicit brain damage. It is thought to reflect a reversible deficit in memory retrieval probably due to memory repression. However, the neural mechanisms underlying this condition are not clear. We used fMRI to investigate neural activity associated with memory retrieval in two patients with dissociative amnesia. For each patient, three categories of face photographs and three categories of people's names corresponding to the photographs were prepared: those of "recognizable" high school friends who were acquainted with and recognizable to the patients, those of "unrecognizable" colleagues who were actually acquainted with but unrecognizable to the patients due to their memory impairments, and "control" distracters who were unacquainted with the patients. During fMRI, the patients were visually presented with these stimuli and asked to indicate whether they were personally acquainted with them. In the comparison of the unrecognizable condition with the recognizable condition, we found increased activity in the pFC and decreased activity in the hippocampus in both patients. After treatment for retrograde amnesia, the altered pattern of brain activation disappeared in one patient whose retrograde memories were recovered, whereas it remained unchanged in the other patient whose retrograde memories were not recovered. Our findings provide direct evidence that memory repression in dissociative amnesia is associated with an altered pattern of neural activity, and they suggest the possibility that the pFC has an important role in inhibiting the activity of the hippocampus in memory repression.

  3. Anthocyanin-dependent anoxygenic photosynthesis in coloured flower petals?

    PubMed Central

    Lysenko, Vladimir; Varduny, Tatyana

    2013-01-01

    Chlorophylless flower petals are known to be composed of non-photosynthetic tissues. Here, we show that the light energy storage that can be photoacoustically measured in flower petals of Petunia hybrida is approximately 10-12%. We found that the supposed chlorophylless photosynthesis is an anoxygenic, anthocyanin-dependent process occurring in blue flower petals (ADAPFP), accompanied by non-respiratory light-dependent oxygen uptake and a 1.5-fold photoinduced increase in ATP levels. Using a simple, adhesive tape stripping technique, we have obtained a backside image of an intact flower petal epidermis, revealing sword-shaped ingrowths connecting the cell wall and vacuole, which is of interest for the further study of possible vacuole-related photosynthesis. Approaches to the interpretations of ADAPFP are discussed, and we conclude that these results are not impossible in terms of the known photochemistry of anthocyanins. PMID:24284801

  4. Optical properties of anthocyanins in the gas phase

    NASA Astrophysics Data System (ADS)

    Ge, Xiaochuan; Calzolari, Arrigo; Baroni, Stefano

    2015-01-01

    The gas-phase optical properties of the six most common anthocyanins are studied using time-dependent density-functional theory. Different anthocyanins are classified into three groups, according to the number of low-frequency peaks displayed in the UV-vis spectrum. This behavior is analyzed in terms of one-electron transitions and interaction effects, the latter being rationalized using a suitable double-pole model. Moving from PBE to hybrid exchange-correlation functionals results in a hypsochromic shift of the optical gap. While the colors thus predicted do not quite match those observed in solution, thus highlighting the importance of solvation effects, adoption of hybrid functionals remarkably determines a greater chromatic uniformity of different molecules, in qualitative agreement with experimental evidence in acidic solutions.

  5. Grape anthocyanin oligomerization: a putative mechanism for red color stabilization?

    PubMed

    Oliveira, Joana; Brás, Natércia F; da Silva, Mara Alhinho; Mateus, Nuno; Parola, A Jorge; de Freitas, Victor

    2014-09-01

    The equilibrium forms of malvidin-3-O-glucoside trimer present in grape skins were studied in aqueous solution at different pH values through UV-Visible spectroscopy. It was observed that the reactivity of this compound is strongly dominated by acid-base chemistry (pKa1=3.61±0.03; pKa2=6.83±0.06), with the reaction sequence hydration-tautomerization-isomerization accounting less than 10% of the overall reactivity. The decrease of hydration of this flavylium cation derivative when compared to the original anthocyanins results from the formation of a cluster of the pigment with a high-energy of solvation that inhibits the access of water molecules to the flavylium cation core preventing by this way the hydration reactions. Overall of these results raise the hypothesis that polymerization may be a natural stabilization mechanism for the red color of anthocyanins.

  6. Anthocyanin-dependent anoxygenic photosynthesis in coloured flower petals?

    NASA Astrophysics Data System (ADS)

    Lysenko, Vladimir; Varduny, Tatyana

    2013-11-01

    Chlorophylless flower petals are known to be composed of non-photosynthetic tissues. Here, we show that the light energy storage that can be photoacoustically measured in flower petals of Petunia hybrida is approximately 10-12%. We found that the supposed chlorophylless photosynthesis is an anoxygenic, anthocyanin-dependent process occurring in blue flower petals (ADAPFP), accompanied by non-respiratory light-dependent oxygen uptake and a 1.5-fold photoinduced increase in ATP levels. Using a simple, adhesive tape stripping technique, we have obtained a backside image of an intact flower petal epidermis, revealing sword-shaped ingrowths connecting the cell wall and vacuole, which is of interest for the further study of possible vacuole-related photosynthesis. Approaches to the interpretations of ADAPFP are discussed, and we conclude that these results are not impossible in terms of the known photochemistry of anthocyanins.

  7. Neutrophil elastase, an innate immunity effector molecule, represses flagellin transcription in Pseudomonas aeruginosa.

    PubMed

    Sonawane, Avinash; Jyot, Jeevan; During, Russell; Ramphal, Reuben

    2006-12-01

    Recognition of pathogen-associated molecular patterns (PAMPs) by pattern recognition receptors triggers an innate immune response to colonizing or invading bacteria. Conversely, many bacteria have evolved mechanisms to dampen this response by downregulating the synthesis of such PAMPs. We have previously demonstrated that Pseudomonas aeruginosa growing in mucopurulent human respiratory mucus from cystic fibrosis patients represses the expression of its flagellin, a potent stimulant of the innate immune response. Here we demonstrate that this phenomenon occurs in response to the presence of neutrophil elastase in such mucus. Nonpurulent mucus from animals had no such repressive effect. Furthermore, lysed neutrophils from human blood reproduced the flagellin-repressive effect ex mucus and, significantly, had no effect on the viability of this organism. Neutrophil elastase, a component of the innate host defense system, has been described to be bactericidal for gram-negative bacteria and to degrade bacterial virulence factors. Thus, the resistance of P. aeruginosa to the bactericidal effect of neutrophil elastase, as well as this organism's ability to sense this enzyme's presence and downregulate the synthesis of a PAMP, may be the key factors in allowing P. aeruginosa to colonize the lungs. These findings demonstrate the dynamic nature of this bacterium's response to host defenses that ensures its success as a colonizer and also highlights the dual nature of defense molecules that confer advantages and disadvantages to both hosts and pathogens. PMID:16982831

  8. Inhibition of tumor cell growth by Sigma1 ligand mediated translational repression

    SciTech Connect

    Kim, Felix J.; Schrock, Joel M.; Spino, Christina M.; Marino, Jacqueline C.; Pasternak, Gavril W.

    2012-09-21

    Highlights: Black-Right-Pointing-Pointer Sigma1 ligand treatment mediates decrease in tumor cell mass. Black-Right-Pointing-Pointer Identification of a Sigma1 ligand with reversible translational repressor actions. Black-Right-Pointing-Pointer Demonstration of a role for Sigma1 in cellular protein synthesis. -- Abstract: Treatment with sigma1 receptor (Sigma1) ligands can inhibit cell proliferation in vitro and tumor growth in vivo. However, the cellular pathways engaged in response to Sigma1 ligand treatment that contribute to these outcomes remain largely undefined. Here, we show that treatment with putative antagonists of Sigma1 decreases cell mass. This effect corresponds with repressed cap-dependent translation initiation in multiple breast and prostate cancer cell lines. Sigma1 antagonist treatment suppresses phosphorylation of translational regulator proteins p70S6K, S6, and 4E-BP1. RNAi-mediated knockdown of Sigma1 also results in translational repression, consistent with the effects of antagonist treatment. Sigma1 antagonist mediated translational repression and decreased cell size are both reversible. Together, these data reveal a role for Sigma1 in tumor cell protein synthesis, and demonstrate that small molecule Sigma1 ligands can be used as modulators of protein translation.

  9. Effect of calcium on strawberry fruit flavonoid pathway gene expression and anthocyanin accumulation.

    PubMed

    Xu, Wenping; Peng, Hui; Yang, Tianbao; Whitaker, Bruce; Huang, Luhong; Sun, Jianghao; Chen, Pei

    2014-09-01

    Two diploid woodland strawberry (Fragaria vesca) inbred lines, Ruegen F7-4 (red fruit-bearing) and YW5AF7 (yellow fruit-bearing) were used to study the regulation of anthocyanin biosynthesis in fruit. Ruegen F7-4 fruit had similar total phenolics and anthocyanin contents to commercial octoploid (F. × ananassa) cultivar Seascape, while YW5AF7 exhibited relatively low total phenolics content and no anthocyanin accumulation. Foliar spray of CaCl2 boosted fruit total phenolics content, especially anthocyanins, by more than 20% in both Seascape and RF7-4. Expression levels of almost all the flavonoid pathway genes were comparable in Ruegen F7-4 and YW5AF7 green-stage fruit. However, at the turning and ripe stages, key anthocyanin structural genes, including flavanone 3-hydroxylase (F3H1), dihydroflavonol 4-reductase (DFR2), anthocyanidin synthase (ANS1), and UDP-glucosyltransferase (UGT1), were highly expressed in Ruegen F7-4 compared with YW5AF7 fruit. Calcium treatment further stimulated the expression of those genes in Ruegen F7-4 fruit. Anthocyanins isolated from petioles of YW5AF7 and Ruegen F-7 had the same HPLC-DAD profile, which differed from that of Ruegen F-7 fruit anthocyanins. All the anthocyanin structural genes except FvUGT1 were detected in petioles of YW5AF7 and Ruegen F-7. Taken together, these results indicate that the "yellow" gene in YW5AF7 is a fruit specific regulatory gene(s) for anthocyanin biosynthesis. Calcium can enhance accumulation of anthocyanins and total phenolics in fruit possibly via upregulation of anthocyanin structural genes. Our results also suggest that the anthocyanin biosynthesis machinery in petioles is different from that in fruit. PMID:25036468

  10. Effect of calcium on strawberry fruit flavonoid pathway gene expression and anthocyanin accumulation.

    PubMed

    Xu, Wenping; Peng, Hui; Yang, Tianbao; Whitaker, Bruce; Huang, Luhong; Sun, Jianghao; Chen, Pei

    2014-09-01

    Two diploid woodland strawberry (Fragaria vesca) inbred lines, Ruegen F7-4 (red fruit-bearing) and YW5AF7 (yellow fruit-bearing) were used to study the regulation of anthocyanin biosynthesis in fruit. Ruegen F7-4 fruit had similar total phenolics and anthocyanin contents to commercial octoploid (F. × ananassa) cultivar Seascape, while YW5AF7 exhibited relatively low total phenolics content and no anthocyanin accumulation. Foliar spray of CaCl2 boosted fruit total phenolics content, especially anthocyanins, by more than 20% in both Seascape and RF7-4. Expression levels of almost all the flavonoid pathway genes were comparable in Ruegen F7-4 and YW5AF7 green-stage fruit. However, at the turning and ripe stages, key anthocyanin structural genes, including flavanone 3-hydroxylase (F3H1), dihydroflavonol 4-reductase (DFR2), anthocyanidin synthase (ANS1), and UDP-glucosyltransferase (UGT1), were highly expressed in Ruegen F7-4 compared with YW5AF7 fruit. Calcium treatment further stimulated the expression of those genes in Ruegen F7-4 fruit. Anthocyanins isolated from petioles of YW5AF7 and Ruegen F-7 had the same HPLC-DAD profile, which differed from that of Ruegen F-7 fruit anthocyanins. All the anthocyanin structural genes except FvUGT1 were detected in petioles of YW5AF7 and Ruegen F-7. Taken together, these results indicate that the "yellow" gene in YW5AF7 is a fruit specific regulatory gene(s) for anthocyanin biosynthesis. Calcium can enhance accumulation of anthocyanins and total phenolics in fruit possibly via upregulation of anthocyanin structural genes. Our results also suggest that the anthocyanin biosynthesis machinery in petioles is different from that in fruit.

  11. PH-dependent forms of red wine anthocyanins as antioxidants.

    PubMed

    Lapidot, T; Harel, S; Akiri, B; Granit, R; Kanner, J

    1999-01-01

    Anthocyanins are one of the main classes of flavonoids in red wines, and they appear to contribute significantly to the powerful antioxidant properties of the flavonoids. In grapes and wines the anthocyanins are in the flavylium form. However, during digestion they may reach higher pH values, forming the carbinol pseudo-base, quinoidal-base, or the chalcone, and these compounds appear to be absorbed from the gut into the blood system. The antioxidant activity of these compounds, in several metal-catalyzed lipid oxidation model systems, was evaluated in comparison with other antioxidants. The pseudo-base and quinoidal-base malvidin 3-glucoside significantly inhibited the peroxidation of linoleate by myoglobin. Both compounds were found to work better than catechin, a well-known antioxidant. In a membrane lipid peroxidation system, the effectiveness of the antioxidant was dependent on the catalyst: In the presence of H(2)O(2)-activated myoglobin, the inhibition efficiency of the antioxidant was malvidin 3-glucoside > catechin > malvidin > resveratrol. However, in the presence of an iron redox cycle catalyzer, the order of effectiveness was resveratrol > malvidin 3-glucoside = malvidin > catechin. The pH-transformed forms of the anthocyanins remained effective antioxidants in these systems, and their I(50) values were between 0.5 and 6.2 microM. PMID:10563851

  12. PH-dependent forms of red wine anthocyanins as antioxidants.

    PubMed

    Lapidot, T; Harel, S; Akiri, B; Granit, R; Kanner, J

    1999-01-01

    Anthocyanins are one of the main classes of flavonoids in red wines, and they appear to contribute significantly to the powerful antioxidant properties of the flavonoids. In grapes and wines the anthocyanins are in the flavylium form. However, during digestion they may reach higher pH values, forming the carbinol pseudo-base, quinoidal-base, or the chalcone, and these compounds appear to be absorbed from the gut into the blood system. The antioxidant activity of these compounds, in several metal-catalyzed lipid oxidation model systems, was evaluated in comparison with other antioxidants. The pseudo-base and quinoidal-base malvidin 3-glucoside significantly inhibited the peroxidation of linoleate by myoglobin. Both compounds were found to work better than catechin, a well-known antioxidant. In a membrane lipid peroxidation system, the effectiveness of the antioxidant was dependent on the catalyst: In the presence of H(2)O(2)-activated myoglobin, the inhibition efficiency of the antioxidant was malvidin 3-glucoside > catechin > malvidin > resveratrol. However, in the presence of an iron redox cycle catalyzer, the order of effectiveness was resveratrol > malvidin 3-glucoside = malvidin > catechin. The pH-transformed forms of the anthocyanins remained effective antioxidants in these systems, and their I(50) values were between 0.5 and 6.2 microM.

  13. Engineering the anthocyanin regulatory complex of strawberry (Fragaria vesca)

    PubMed Central

    Lin-Wang, Kui; McGhie, Tony K.; Wang, Mindy; Liu, Yuhui; Warren, Benjamin; Storey, Roy; Espley, Richard V.; Allan, Andrew C.

    2014-01-01

    The woodland strawberry, Fragaria vesca is a model fruit for a number of rosaceous crops. We have engineered altered concentrations of anthocyanin in F. vesca, to determine the impact on plant growth and fruit quality. Anthocyanin concentrations were significantly increased by over-expression or decreased by knock-down of the R2R3 MYB activator, MYB10. In contrast, a potential bHLH partner for MYB10 (bHLH33) did not affect the anthocyanin pathway when knocked down using RNAi constructs. Metabolic analysis of fruits revealed that, of all the polyphenolics surveyed, only cyanidin, and pelargonidin glucoside, and coumaryl hexose were significantly affected by over-expression and knock down of MYB10. Using the F. vesca genome sequence, members of the MYB, bHLH, and WD40 families were examined. Global analysis of gene expression and targeted qPCR analysis of biosynthetic genes and regulators confirmed the effects of altering MYB10 expression, as well as the knock-down of bHLH33. Other members of the MYB transcription factor family were affected by the transgenes. Transient expression of strawberry genes in Nicotiana benthamiana revealed that MYB10 can auto-regulate itself, and potential repressors of MYB10. In tobacco, MYB10's activation of biosynthetic steps is inhibited by the strawberry repressor MYB1. PMID:25477896

  14. Characterisation and stability of anthocyanins in purple-fleshed sweet potato P40.

    PubMed

    Xu, Jianteng; Su, Xiaoyu; Lim, Soyoung; Griffin, Jason; Carey, Edward; Katz, Benjamin; Tomich, John; Smith, J Scott; Wang, Weiqun

    2015-11-01

    Purple-fleshed sweet potato P40 has been shown to prevent colorectal cancer in a murine model. This study is to identify anthocyanins by using HPLC/MS-MS and assess the stability during various cooking conditions. P40 possesses a high content of anthocyanins up to 14 mg/g dry matter. Total 12 acylated anthocyanins are identified. Top three anthocyanins, e.g., cyanidin 3-caffeoyl-p-hydroxybenzoyl sophoroside-5-glucoside, peonidin 3-caffeoyl sophoroside-5-glucoside, and cyanidin 3-(6"-caffeoyl-6"-feruloylsophoroside)-5-glucoside, account for half of the anthocyanin contents. Over 80% of anthocyanins measured by acid hydrolysis were cyanidin derivatives, indicating P40 is unique when compared with other purple-fleshed sweet potatoes that usually contain more peonidin than cyanidin. Steaming, pressure cooking, microwaving, and frying but not baking significantly reduced 8-16% of total anthocyanin contents. Mono-acylated anthocyanins showed a higher resistance against heat than di- and non-acylated. Among of which, cyanidin 3-p-hydroxybenzoylsophoroside-5-glucoside exhibited the best thermal stability. The stable acylated and cyanidin-predominated anthocyanins in P40 may provide extra benefits for cancer prevention.

  15. Absorption and excretion of black currant anthocyanins in humans and watanabe heritable hyperlipidemic rabbits.

    PubMed

    Nielsen, Inge Lise F; Dragsted, Lars O; Ravn-Haren, Gitte; Freese, Riitta; Rasmussen, Salka E

    2003-04-23

    Anthocyanins are thought to protect against cardiovascular diseases. Watanabe heritable hyperlipidemic (WHHL) rabbits are hypercholesterolemic and used as a model of the development of atherosclerosis. To compare the uptake and excretion of anthocyanins in humans and WHHL rabbits, single-dose black currant anthocyanin studies were performed. Procedures for workup and analyses of urine and plasma samples containing anthocyanins were developed with high recoveries (99 and 81%, respectively) and low limits of quantification (> or =6.6 and > or =1.1 nM, respectively). The excretion and absorption of anthocyanins from black currant juice were found to be within the same order of magnitude in the two species regarding urinary excretion within the first 4 h (rabbits, 0.035%; humans, 0.072%) and t(max) (rabbits, approximately 30 min; humans, approximately 45 min). A food matrix effect was detected in rabbits, resulting in the absorption of a higher proportion of the anthocyanins from black currant juice than from an aqueous citric acid matrix. In humans the absorption and urinary excretion of anthocyanins from black currant juice were found to be proportional with dose and not influenced by the ingestion of a rice cake. In both species a larger proportion of the anthocyanin rutinosides than of the glucosides was absorbed, whereas the structure of the aglycon had no influence on the absorption and excretion. The anthocyanins had no effect in rabbits on the antioxidant capacity of plasma measured as Trolox equivalent antioxidant capacity and ferruc reducing ability of plasma. PMID:12696978

  16. Characterisation and stability of anthocyanins in purple-fleshed sweet potato P40.

    PubMed

    Xu, Jianteng; Su, Xiaoyu; Lim, Soyoung; Griffin, Jason; Carey, Edward; Katz, Benjamin; Tomich, John; Smith, J Scott; Wang, Weiqun

    2015-11-01

    Purple-fleshed sweet potato P40 has been shown to prevent colorectal cancer in a murine model. This study is to identify anthocyanins by using HPLC/MS-MS and assess the stability during various cooking conditions. P40 possesses a high content of anthocyanins up to 14 mg/g dry matter. Total 12 acylated anthocyanins are identified. Top three anthocyanins, e.g., cyanidin 3-caffeoyl-p-hydroxybenzoyl sophoroside-5-glucoside, peonidin 3-caffeoyl sophoroside-5-glucoside, and cyanidin 3-(6"-caffeoyl-6"-feruloylsophoroside)-5-glucoside, account for half of the anthocyanin contents. Over 80% of anthocyanins measured by acid hydrolysis were cyanidin derivatives, indicating P40 is unique when compared with other purple-fleshed sweet potatoes that usually contain more peonidin than cyanidin. Steaming, pressure cooking, microwaving, and frying but not baking significantly reduced 8-16% of total anthocyanin contents. Mono-acylated anthocyanins showed a higher resistance against heat than di- and non-acylated. Among of which, cyanidin 3-p-hydroxybenzoylsophoroside-5-glucoside exhibited the best thermal stability. The stable acylated and cyanidin-predominated anthocyanins in P40 may provide extra benefits for cancer prevention. PMID:25976796

  17. Charge-transfer complexation as a general phenomenon in the copigmentation of anthocyanins.

    PubMed

    Ferreira da Silva, Palmira; Lima, João C; Freitas, Adilson A; Shimizu, Karina; Maçanita, Antonio L; Quina, Frank H

    2005-08-18

    Color intensification of anthocyanin solutions in the presence of natural polyphenols (copigmentation) is re-interpreted in terms of charge transfer from the copigment to the anthocyanin. Flavylium cations are shown to be excellent electron acceptors (E(red) approximately -0.3 V vs SCE). It is also demonstrated, for a large series of anthocyanin-copigment pairs, that the standard Gibbs free energy of complex formation decreases linearly with EA(Anthoc) - IP(Cop), the difference between the electron affinity of the anthocyanin, EA(Anthoc), and the ionization potential of the copigment, IP(Cop). Based on this correlation, copigmentation strengths of potential candidates for copigments can be predicted.

  18. Early Autumn Senescence in Red Maple (Acer rubrum L.) Is Associated with High Leaf Anthocyanin Content.

    PubMed

    Anderson, Rachel; Ryser, Peter

    2015-08-05

    Several theories exist about the role of anthocyanins in senescing leaves. To elucidate factors contributing to variation in autumn leaf anthocyanin contents among individual trees, we analysed anthocyanins and other leaf traits in 27 individuals of red maple (Acer rubrum L.) over two growing seasons in the context of timing of leaf senescence. Red maple usually turns bright red in the autumn, but there is considerable variation among the trees. Leaf autumn anthocyanin contents were consistent between the two years of investigation. Autumn anthocyanin content strongly correlated with degree of chlorophyll degradation mid to late September, early senescing leaves having the highest concentrations of anthocyanins. It also correlated positively with leaf summer chlorophyll content and dry matter content, and negatively with specific leaf area. Time of leaf senescence and anthocyanin contents correlated with soil pH and with canopy openness. We conclude that the importance of anthocyanins in protection of leaf processes during senescence depends on the time of senescence. Rather than prolonging the growing season by enabling a delayed senescence, autumn anthocyanins in red maple in Ontario are important when senescence happens early, possibly due to the higher irradiance and greater danger of oxidative damage early in the season.

  19. Isolation of high-purity anthocyanin mixtures and monomers from blueberries using combined chromatographic techniques.

    PubMed

    Wang, Erlei; Yin, Yongguang; Xu, Caina; Liu, Jingbo

    2014-01-31

    Research on the isolation and preparation of anthocyanins has intensified in recent years because of the requirements of quantitative and bioactive analyses. However, simple and effective methods for the scale purification of pure anthocyanins from natural products are rarely reported. In this study, high-purity anthocyanin mixtures and monomers were successfully isolated from wild blueberries using a combination of column chromatography and semi-preparative HPLC. We established an effective elution system to separate high-purity anthocyanin mixtures with aqueous ethanol containing 0.01% HCl first in an Amberlite XAD-7HP column (ethanol/H2O=35:65) and then in a Sephadex LH-20 column (ethanol/H2O=25:75). Crude anthocyanin extracts were isolated using the Amberlite column, and a purity of 32% was obtained based on UV-vis analysis. Three fractions of anthocyanin mixtures were isolated from the crude extracts using the Sephadex column with purities ranging from 59% to 68%. Three pure monomeric anthocyanins of malvidin-3-O-glucoside, petunidin-3-O-glucoside, and delphinidin-3-O-glucoside were also isolated by semi-preparative HPLC and identified by HPLC-DAD-ESI-MS/MS. The purities of these anthocyanins were determined by analytical HPLC and estimated to be 97.7%, 99.3%, and 95.4%, respectively. The results of this study may help promote the purification of anthocyanins from most blueberry varieties as well as from other plant materials.

  20. Effects of growing conditions on purple corncob (Zea mays L.) anthocyanins.

    PubMed

    Jing, Pu; Noriega, Victor; Schwartz, Steven J; Giusti, M Mónica

    2007-10-17

    Purple corn ( Zea mays L.) has been used for centuries as a natural food colorant in South America and, more recently, in Asia and Europe. However, limited information is available on the factors affecting their anthocyanin concentration and profiles. In this study, 18 purple corn samples grown under different conditions in Peru were evaluated for quantitative and qualitative anthocyanin composition as well as total phenolics. High variability was observed on monomeric anthocyanin and phenolic contents with yields ranging from 290 to 1333 mg/100 g dry weight (DW) and from 950 to 3516 mg/100 g DW, respectively, while 30.5-47.1% of the total phenolics were anthocyanins. The major anthocyanins present were cyanidin-3-glucoside, pelargonidin-3-glucoside, peonidin-3-glucoside, cyanidin-3-maloylglucoside, pelargonidin-3-maloylglucoside, and peonidin-3-maloylglucoside, and 35.6-54.0% of the anthocyanins were acylated. Potassium sources/concentrations on the soil and seedling density did not significantly affect anthocyanin composition. The growing location affected anthocyanin levels and the percentage of anthocyanins to total phenolics ( p < 0.01) and should be taken into account when choosing a material for color production. PMID:17880157

  1. Fluorescence of anthocyanin pigments in plant extracts at various pH

    NASA Astrophysics Data System (ADS)

    Pliszka, Barbara; Olszewska, Teresa; Drabent, Regina

    2001-07-01

    The fluorescence properties of anthocyanin pigments in extracts of red cabbage, Brassica oleracea, have been studied. The fluorescence spectra and fluorescence excitation spectra have been measured with absorption spectra of anthocyanins in extracts at pH 2 and pH 7. The results of the researches show that kinds of fluorescent anthocyanins (or/and other compounds) depend on pH conditions of red cabbage extracts. The properly chosen parameters of fluorescence measurement allow to distinguish spectrally two different fluorescent anthocyanin compounds in extract at pH 2 in comparison to pH 7, where three fluorescent compounds have been found.

  2. Early Autumn Senescence in Red Maple (Acer rubrum L.) Is Associated with High Leaf Anthocyanin Content

    PubMed Central

    Anderson, Rachel; Ryser, Peter

    2015-01-01

    Several theories exist about the role of anthocyanins in senescing leaves. To elucidate factors contributing to variation in autumn leaf anthocyanin contents among individual trees, we analysed anthocyanins and other leaf traits in 27 individuals of red maple (Acer rubrum L.) over two growing seasons in the context of timing of leaf senescence. Red maple usually turns bright red in the autumn, but there is considerable variation among the trees. Leaf autumn anthocyanin contents were consistent between the two years of investigation. Autumn anthocyanin content strongly correlated with degree of chlorophyll degradation mid to late September, early senescing leaves having the highest concentrations of anthocyanins. It also correlated positively with leaf summer chlorophyll content and dry matter content, and negatively with specific leaf area. Time of leaf senescence and anthocyanin contents correlated with soil pH and with canopy openness. We conclude that the importance of anthocyanins in protection of leaf processes during senescence depends on the time of senescence. Rather than prolonging the growing season by enabling a delayed senescence, autumn anthocyanins in red maple in Ontario are important when senescence happens early, possibly due to the higher irradiance and greater danger of oxidative damage early in the season. PMID:27135339

  3. Cloning and expression analyses of the anthocyanin biosynthetic genes in mulberry plants.

    PubMed

    Qi, Xiwu; Shuai, Qin; Chen, Hu; Fan, Li; Zeng, Qiwei; He, Ningjia

    2014-10-01

    Anthocyanins are natural food colorants produced by plants that play important roles in their growth and development. Mulberry fruits are rich in anthocyanins, which are the most important active components of mulberry and have many potentially beneficial effects on human health. The study of anthocyanin biosynthesis will bring benefits for quality improvement and industrial exploration of mulberry fruits. In the present study, nine putative genes involved in anthocyanin biosynthesis in mulberry plants were identified and cloned. Sequence analysis revealed that the mulberry anthocyanin biosynthetic genes were conserved and had counterparts in other plants. Spatial transcriptional analysis showed detectable expression of eight of these genes in different tissues. The results of expression and UPLC analyses in two mulberry cultivars with differently colored fruit indicated that anthocyanin concentrations correlated with the expression levels of genes associated with anthocyanin biosynthesis including CHS1, CHI, F3H1, F3'H1, and ANS during the fruit ripening process. The present studies provide insight into anthocyanin biosynthesis in mulberry plants and may facilitate genetic engineering for improvement of the anthocyanin content in mulberry fruit. PMID:24748075

  4. The natural product peiminine represses colorectal carcinoma tumor growth by inducing autophagic cell death.

    PubMed

    Lyu, Qing; Tou, Fangfang; Su, Hong; Wu, Xiaoyong; Chen, Xinyi; Zheng, Zhi

    2015-06-19

    Autophagy is evolutionarily conservative in eukaryotic cells that engulf cellular long-lived proteins and organelles, and it degrades the contents through fusion with lysosomes, via which the cell acquires recycled building blocks for the synthesis of new molecules. In this study, we revealed that peiminine induces cell death and enhances autophagic flux in colorectal carcinoma HCT-116 cells. We determined that peiminine enhances the autophagic flux by repressing the phosphorylation of mTOR through inhibiting upstream signals. Knocking down ATG5 greatly reduced the peiminine-induced cell death in wild-type HCT-116 cells, while treating Bax/Bak-deficient cells with peiminine resulted in significant cell death. In summary, our discoveries demonstrated that peiminine represses colorectal carcinoma cell proliferation and cell growth by inducing autophagic cell death.

  5. Regulation of lac Operon Expression: Reappraisal of the Theory of Catabolite Repression

    PubMed Central

    Wanner, Barry L.; Kodaira, Ryoji; Neidhardt, Frederick C.

    1978-01-01

    The physiological state of Escherichia coli with respect to (permanent) catabolite repression was assessed by measuring the steady-state level of β-galactosidase in induced or in constitutive cells under a variety of growth conditions. Four results were obtained. (i) Catabolite repression had a major effect on fully induced or constitutive expression of the lac gene, and the magnitude of this effect was found to be dependent on the promoter structure; cells with a wild-type lac promoter showed an 18-fold variation in lac expression, and cells with the lacP37 (formerly lac-L37) promoter exhibited several hundred-fold variation. (ii) Exogenous adenosine cyclic 3′,5′-monophosphoric acid (cAMP) could not abolish catabolite repression, even though several controls demonstrated that cAMP was entering the cells in significant amounts. (Rapid intracellular degradation of cAMP could not be ruled out.) (iii) Neither the growth rate nor the presence of biosynthetic products altered the degree of catabolite repression; all variation could be related to the catabolites present in the growth medium. (iv) Slowing by imposing an amino acid restriction decreased the differential rate of β-galactosidase synthesis from the wild-type lac promoter when bacteria were cultured in either the absence or presence of cAMP; this decreased lac expression also occurred when the bacteria harbored the catabolite-insensitive lacP5 (formerly lacUV5) promoter mutation. These findings support the idea that (permanent) catabolite repression is set by the catabolites in the growth medium and may not be related to an imbalance between catabolism and anabolism. PMID:214424

  6. Zeste maintains repression of Ubx transgenes: Support for a new model of polycomb repression

    SciTech Connect

    Hur, Man-Wook; Laney, Jeffrey D.; Jeon, Sang-Hack; Ali, Janann; Biggin, Mark D.

    2001-09-01

    During late embryogenesis, the expression domains of homeotic genes are maintained by two groups of ubiquitously expressed regulators: the Polycomb repressors and the Trithorax activators. It is not known how the activities of the two maintenance systems are initially targeted to the correct genes. Zeste and GAGA are sequence specific DNA binding proteins previously shown to be Trithorax group activators of the homeotic gene Ultrabithorax (Ubx). Here we demonstrate that Zeste and GAGA DNA binding sites at the proximal promoter are also required to maintain, but not to initiate, repression of Ubx. Further, the repression mediated by Zeste DNA binding site is abolished in zeste null embryos. These data imply that Zeste and probably GAGA mediate Polycomb repression. We present a model in which the dual transcriptional activities of Zeste and GAGA are an essential component of the mechanism that chooses which maintenance system is to be targeted to a given promoter.

  7. Identification, content and distribution of anthocyanins and low molecular weight anthocyanin-derived pigments in Spanish commercial red wines.

    PubMed

    Blanco-Vega, Dora; Gómez-Alonso, Sergio; Hermosín-Gutiérrez, Isidro

    2014-09-01

    The content and distribution of low molecular weight red wine pigments (anthocyanins, flavanol-anthocyanins adducts and pyranoanthocyanins) has been analysed in 283 wine samples. A total of 90 red wine pigments were identified and up to 68 of them quantified in most of the wine samples. The content of the different pigments classes accounted for wide ranges of values, because of the diversity of the commercial wines regarding grape cultivar and age. Garnacha young wines were prone to contain higher hydroxyphenyl-pyranoanthocyanin concentrations. The aging had an effect of making uniform the concentrations and molar percentages of every type of pigments, and only slight differences among wine groups were found for B-type vitisins (highest values for Syrah wines) and 10-hydroxyphenyl-pyranoanthocyanins (highest values for Merlot wines). Among Tempranillo wines, the ethylidene-bridged flavanol-anthocyanin adducts were the most affected by disappearance during aging, whereas hydroxyphenyl-pyranoanthocyanins increased their contribution in most of those aged wines.

  8. AN9, a Petunia Glutathione S-Transferase Required for Anthocyanin Sequestration, Is a Flavonoid-Binding Protein1

    PubMed Central

    Mueller, Lukas A.; Goodman, Christopher D.; Silady, Rebecca A.; Walbot, Virginia

    2000-01-01

    AN9 is a glutathione S-transferase from petunia (Petunia hybrida) required for efficient anthocyanin export from the site of synthesis in the cytoplasm into permanent storage in the vacuole. For many xenobiotics it is well established that a covalent glutathione (GSH) tag mediates recognition of molecules destined for vacuolar sequestration by a tonoplast-localized ATP-binding cassette pump. Here we inquired whether AN9 catalyzes the formation of GSH conjugates with flavonoid substrates. Using high-performance liquid chromatography analysis of reaction mixtures containing enzyme, GSH, and flavonoids, including anthocyanins, we could detect neither conjugates nor a decrease in the free thiol concentration. These results suggest that no conjugate is formed in vitro. However, AN9 was shown to bind flavonoids using three assays: inhibition of the glutathione S-transferase activity of AN9 toward the common substrate 1-chloro 2,4-dinitrobenzene, equilibrium dialysis, and tryptophan quenching. We conclude that AN9 is a flavonoid-binding protein, and propose that in vivo it serves as a cytoplasmic flavonoid carrier protein. PMID:10938372

  9. Modulation of flavonoid biosynthetic pathway genes and anthocyanins due to virus infection in grapevine (Vitis vinifera L.) leaves

    PubMed Central

    2010-01-01

    leaves when compared to virus-free green leaves. Conclusions The results, the first example to our knowledge, showed that modulation of the flavonoid biosynthetic pathway occurred in GLRaV-3-infected leaves of a red-fruited wine grape cultivar (cv. Merlot) leading to de novo synthesis of two classes of anthocyanins. These anthocyanins have contributed to the expression of reddish-purple color of virus-infected grapevine leaves exhibiting GLRD symptoms. PMID:20731850

  10. Anthocyanin indexes, quercetin, kaempferol, and myricetin concentration in leaves and fruit of Abutilon theophrasti Medik. genetic resources

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Anthocyanin indexes, quercetin, kaempferol, and myricetin may provide industry with potential new medicines or nutraceuticals. Velvetleaf (Abutilon theophrasti Medik) leaves from 42 accessions were analyzed for anthocyanin indexes while both leaves and fruit were used for quercetin, kaempferol, and ...

  11. Changes in the color, chemical stability and antioxidant capacity of thermally treated anthocyanin aqueous solution over storage.

    PubMed

    Sui, Xiaonan; Bary, Solène; Zhou, Weibiao

    2016-02-01

    Many anthocyanin-containing foods are thermally processed to ensure their safety, and stored for some time before being consumed. However, the combination of thermal processing and subsequent storage has a significant impact on anthocyanins. This study aimed to investigate the color, chemical stability, and antioxidant capacity of thermally treated anthocyanin aqueous solutions during storage at 4, 25, 45, and 65 °C, respectively. Anthocyanin aqueous solutions were thermally treated before storage. Results showed that the degradation rate of anthocyanins in aqueous solutions was much faster than those in real food. The color of the anthocyanin aqueous solutions changed dramatically during storage. The anthocyanin aqueous solutions stored at 4 °C showed the best chemical stability. Interestingly, the antioxidant capacity of the anthocyanin aqueous solutions stored at lower temperatures remained the same; however, the antioxidant capacity of those thermally treated at 120 or 140 °C and stored at 45 or 65 °C significantly decreased.

  12. The anthocyanin reduced Tomato Mutant Demonstrates the Role of Flavonols in Tomato Lateral Root and Root Hair Development1[W][OPEN

    PubMed Central

    Maloney, Gregory S.; DiNapoli, Kathleen T.; Muday, Gloria K.

    2014-01-01

    This study utilized tomato (Solanum lycopersicum) mutants with altered flavonoid biosynthesis to understand the impact of these metabolites on root development. The mutant anthocyanin reduced (are) has a mutation in the gene encoding FLAVONOID 3-HYDROXYLASE (F3H), the first step in flavonol synthesis, and accumulates higher concentrations of the F3H substrate, naringenin, and lower levels of the downstream products kaempferol, quercetin, myricetin, and anthocyanins, than the wild type. Complementation of are with the p35S:F3H transgene reduced naringenin and increased flavonols to wild-type levels. The initiation of lateral roots is reduced in are, and p35S:F3H complementation restores wild-type root formation. The flavonoid mutant anthocyanin without has a defect in the gene encoding DIHYDROFLAVONOL REDUCTASE, resulting in elevated flavonols and the absence of anthocyanins and displays increased lateral root formation. These results are consistent with a positive role of flavonols in lateral root formation. The are mutant has increased indole-3-acetic acid transport and greater sensitivity to the inhibitory effect of the auxin transport inhibitor naphthylphthalamic acid on lateral root formation. Expression of the auxin-induced reporter (DR5-β-glucuronidase) is reduced in initiating lateral roots and increased in primary root tips of are. Levels of reactive oxygen species are elevated in are root epidermal tissues and root hairs, and are forms more root hairs, consistent with a role of flavonols as antioxidants that modulate root hair formation. Together, these experiments identify positive roles of flavonols in the formation of lateral roots and negative roles in the formation of root hairs through the modulation of auxin transport and reactive oxygen species, respectively. PMID:25006027

  13. An upstream open reading frame represses expression of Lc, a member of the R/B family of maize transcriptional activators

    SciTech Connect

    Damiani, R.D. Jr.; Wessler, S.R. )

    1993-09-01

    The R/B genes of maize encode a family of basic helix-loop-helix proteins that determine where and when the anthocyanin-pigment pathway will be expressed in the plant. Previous studies showed that allelic diversity among family members reflects differences in gene expression, specifically in transcription initiation. The authors present evidence that the R gene Lc is under translational control. They demonstrate that the 235-nt transcript leader of Lc represses expression 25- to 30-fold in an in vivo assay. Repression is mediated by the presence in cis of a 38-codon upstream open reading frame. Furthermore, the coding capacity of the upstream open reading frame influences the magnitude of repression. It is proposed that translational control does not contribute to tissue specificity but prevents overexpression of the Lc protein. The diversity of promoter and 5' untranslated leader sequences among the R/B genes provides an opportunity to study the coevolution of transcriptional and translational mechanisms of gene regulation. 36 refs., 5 figs.

  14. Plasma and urine responses are lower for acylated vs nonacylated anthocyanins from raw and cooked purple carrots.

    PubMed

    Kurilich, Anne C; Clevidence, Beverly A; Britz, Steven J; Simon, Philipp W; Novotny, Janet A

    2005-08-10

    The bioavailability of acylated vs nonacylated anthocyanins and the effect of cooking and dose on the comparative bioavailability were investigated in a clinical feeding study using purple carrots as the anthocyanin source. Treatments were purple carrots as follows: 250 g raw (463 micromol of anthocyanins: 400 micromol acylated, 63 micromol nonacylated), 250 g cooked (357 micromol of anthocyanins: 308.5 micromol acylated, 48.5 micromol nonacylated), and 500 g cooked (714 micromol of anthocyanins: 617 micromol acylated, 97 micromol nonacylated). Four of the five carrot anthocyanins were found intact in plasma by 30 min after carrot consumption and peaked between 1.5 and 2.5 h. Acylation of anthocyanins resulted in an 11-14-fold decrease in anthocyanin recovery in urine and an 8-10-fold decrease in anthocyanin recovery in plasma. Cooking increased the recovery of nonacylated anthocyanins but not acylated anthocyanins. Large dose size significantly reduced recovery of both acylated and nonacylated anthocyanins, suggesting saturation of absorption mechanisms.

  15. BEND3 mediates transcriptional repression and heterochromatin organization.

    PubMed

    Khan, Abid; Prasanth, Supriya G

    2015-01-01

    Transcription repression plays a central role in gene regulation. Transcription repressors utilize diverse strategies to mediate transcriptional repression. We have recently demonstrated that BEND3 (BANP, E5R and Nac1 domain) protein represses rDNA transcription by stabilizing a NoRC component. We discuss the role of BEND3 as a global regulator of gene expression and propose a model whereby BEND3 associates with chromatin remodeling complexes to modulate gene expression and heterochromatin organization.

  16. BEND3 mediates transcriptional repression and heterochromatin organization

    PubMed Central

    Khan, Abid; Prasanth, Supriya G

    2015-01-01

    Transcription repression plays a central role in gene regulation. Transcription repressors utilize diverse strategies to mediate transcriptional repression. We have recently demonstrated that BEND3 (BANP, E5R and Nac1 domain) protein represses rDNA transcription by stabilizing a NoRC component. We discuss the role of BEND3 as a global regulator of gene expression and propose a model whereby BEND3 associates with chromatin remodeling complexes to modulate gene expression and heterochromatin organization. PMID:26507581

  17. BEND3 mediates transcriptional repression and heterochromatin organization.

    PubMed

    Khan, Abid; Prasanth, Supriya G

    2015-01-01

    Transcription repression plays a central role in gene regulation. Transcription repressors utilize diverse strategies to mediate transcriptional repression. We have recently demonstrated that BEND3 (BANP, E5R and Nac1 domain) protein represses rDNA transcription by stabilizing a NoRC component. We discuss the role of BEND3 as a global regulator of gene expression and propose a model whereby BEND3 associates with chromatin remodeling complexes to modulate gene expression and heterochromatin organization. PMID:26507581

  18. Tissue bioavailability of anthocyanins from whole tart cherry in healthy rats.

    PubMed

    Kirakosyan, Ara; Seymour, E Mitchell; Wolforth, Janet; McNish, Robert; Kaufman, Peter B; Bolling, Steven F

    2015-03-15

    Our aim was to confirm and identify the presence of tart cherry anthocyanins in several target tissues of healthy rats. Liquid chromatography-mass spectrometry analysis was employed for detection and characterisation of anthocyanin metabolites. It was shown that four native anthocyanins, namely cyanidin 3-glucosylrutinoside, cyanidin 3-rutinoside, cyanidin 3-rutinoside 5-β-D-glucoside, and peonidin 3-rutinoside were differentially distributed among targeted tissues of rats. Bladder and kidney contained more total anthocyanins than all other tissues analysed. It was also revealed that the bioavailability pattern of these native anthocyanins among tissues is varied. The highest concentration of individual anthocyanin cyanidin 3-glucosylrutinoside (2339 picograms/gram of tissue) was detected in bladder, followed by cyanidin 3-rutinoside 5-β-d-glucoside (916 picograms/gram) in the liver of rats. Although the diverse distribution of tart cherry anthocyanins in different rat tissues still requires further explanation, it may provide an evidentiary link between tissue bioavailability and health-enhancing properties of anthocyanins at target sites. PMID:25308638

  19. Rosaceae products: Anthocyanin quality and comparisons between dietary supplements and foods

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Rosaceae (strawberry, cherry, blackberry, red raspberry, and black raspberry) dietary supplements and food products (total n=74) were purchased and analyzed to determine their anthocyanin concentrations and profiles. Eight of the 33 dietary supplements had no detectable anthocyanins (five samples) o...

  20. Issues with fruit dietary supplements in the US - authentication by anthocyanin

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Current fruit-based dietary supplements in the US marketplace have no obligation to meet any fruit-component concentration requirement. For example, berry supplements might be promoted for their high anthocyanin content, but they actually have no standard or minimum anthocyanin threshold for legal s...

  1. Anthocyanin Induces Apoptosis of DU-145 Cells In Vitro and Inhibits Xenograft Growth of Prostate Cancer

    PubMed Central

    Ha, U-Syn; Bae, Woong Jin; Kim, Su Jin; Yoon, Byung Il; Hong, Sung Hoo; Lee, Ji Youl; Hwang, Tae-Kon; Hwang, Sung Yeoun; Wang, Zhiping

    2015-01-01

    Purpose To investigate the effects of anthocyanins extracted from black soybean, which have antioxidant activity, on apoptosis in vitro (in hormone refractory prostate cancer cells) and on tumor growth in vivo (in athymic nude mouse xenograft model). Materials and Methods The growth and viability of DU-145 cells treated with anthocyanins were assessed using the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay and apoptosis was assessed by DNA laddering. Immunoblotting was conducted to evaluate differences in the expressions of p53, Bax, Bcl, androgen receptor (AR), and prostate specific antigen (PSA). To study the inhibitory effects of anthocyanins on tumor growth in vivo, DU-145 tumor xenografts were established in athymic nude mice. The anthocyanin group was treated with daily oral anthocyanin (8 mg/kg) for 14 weeks. After 2 weeks of treatment, DU-145 cells (2×106) were inoculated subcutaneously into the right flank to establish tumor xenografts. Tumor dimensions were measured twice a week using calipers and volumes were calculated. Results Anthocyanin treatment of DU-145 cells resulted in 1) significant increase in apoptosis in a dose-dependent manner, 2) significant decrease in p53 and Bcl-2 expressions (with increased Bax expression), and 3) significant decrease in PSA and AR expressions. In the xenograft model, anthocyanin treatment significantly inhibit tumor growth. Conclusion This study suggests that anthocyanins from black soybean inhibit the progression of prostate cancer in vitro and in a xenograft model. PMID:25510742

  2. Genetic analyses of anthocyanin concentrations and the intensity of red color in onion

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Higher concentrations of anthocyanins in vegetables are important for attractive appearance and may offer health benefits for consumers. The red color of onion bulbs is due primarily to the accumulation of anthocyanins. Segregating haploid plants from the cross of yellow and red inbreds were asexual...

  3. Content and Color Stability of Anthocyanins Isolated from Schisandra chinensis Fruit

    PubMed Central

    Ma, Chunhui; Yang, Lei; Yang, Fengjian; Wang, Wenjie; Zhao, Chunjian; Zu, Yuangang

    2012-01-01

    In this work, a multivariate study based on Box-Behnken Design was used to evaluate the influence of three major variables affecting the performance of the extraction process of Schisandra chinensis anthocyanins. The optimum parameters were 5.5 h extraction time; 1:19 solid-liquid ratio and 260 r/min stirring rate, respectively. The extraction yield of anthocyanins was 29.06 mg/g under the optimum conditions. Moreover, many factors on the impact of heating, ultrasound, microwave treatment and ultraviolet irradiation on content and color stability of anthocyanins from Schisandra chinensis fruit were investigated. The results show that thermal degradation reaction of anthocyanins complies with the first order reaction kinetics, and the correlation coefficient is greater than 0.9950 at 40–80 °C. Ultrasound and microwave treatment has little effect on the stability of anthocyanins, and the extraction time of ultrasound and microwave should be no more than 60 min and 5 min, respectively. The anthocyanins degradation effect of UVC ultraviolet radiation is greater than UVA and UVB; after 9 h ultraviolet radiation, the anthocyanins content degradation of UVC is 23.9 ± 0.7%, and the ΔE* was changed from 62.81 to 76.52 ± 2.3. Through LC-MS analysis, the major composition of Schisandra chinensis anthocyanins was cyanidin-3-O-xylosylrutinoside. PMID:23203065

  4. LC-PDA-EIS/MSn identification of new anthocyanins in purple radish (Raphanus sativus L. variety)

    Technology Transfer Automated Retrieval System (TEKTRAN)

    An LC-PDA-ESI/MSn profiling method was used for a comprehensive study of the anthocyanins of purple Bordeaux radish. This study identified 57 anthocyanins: 23 acylated cyanidin 3-sophoroside-5-diglucosides, 12 acylated cyanidin 3-(glucosylacyl) acylsophoroside-5-diglucosides, and 22 acylated cyanid...

  5. Understanding optimal anthocyanin accumulation of ‘Merlot’ grapes – influence of light exclusion

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Anthocyanins are important components to all red colored fruit, but are absolutely crucial for red wine grapes. Despite a century of research, we still have no concrete understanding of how light and temperature impart their effects on anthocyanin accumulation and composition. Our aim was to elucida...

  6. Functional role of anthocyanins in the leaves of Quintinia serrata A. Cunn.

    PubMed

    Gould, K S; Markham, K R; Smith, R H; Goris, J J

    2000-06-01

    The protective functions that have been ascribed to anthocyanins in leaves can be performed as effectively by a number of other compounds. The possibility that anthocyanins accumulate most abundantly in leaves deficient in other phytoprotective pigments has been tested. Pigment concentrations and their histological distribution were surveyed for a sample of 1000 leaves from a forest population of Quintinia serrata, which displays natural polymorphism in leaf colour. Eight leaf phenotypes were recognized according to their patterns of red coloration. Anthocyanins were observed in almost all combinations of every leaf tissue, but were most commonly located in the vacuoles of photosynthetic cells. Red leaves contained two anthocyanins (Cy-3-glc and Cy-3-gal), epicuticular flavones, epidermal flavonols, hydroxycinnamic acids, chlorophylls, and carotenoids. Green leaves lacked anthocyanins, but had otherwise similar pigment profiles. Foliar anthocyanin levels varied significantly between branches and among trees, but were not correlated to concentrations of other pigments. Anthocyanins were most abundant in older leaves on trees under canopies with south-facing gaps. These data indicate that anthocyanins are associated with photosynthesis, but do not serve an auxiliary phytoprotective role. They may serve to protect shade-adapted chloroplasts from brief exposure to high intensity sunflecks. PMID:10948238

  7. Health Benefits of Anthocyanins and Their Encapsulation for Potential Use in Food Systems: A Review.

    PubMed

    Yousuf, Basharat; Gul, Khalid; Wani, Ali Abas; Singh, Preeti

    2016-10-01

    Anthocyanins are one of the six subgroups of large and widespread group of plant constituents known as flavonoids. These are responsible for the bright and attractive orange, red, purple, and blue colors of most fruits, vegetables, flowers and some cereal grains. More than 600 structurally distinct anthocyanins have been identified in nature. Earlier, anthocyanins were only known for their coloring properties but now interest in anthocyanin pigments has intensified because of their possible health benefits as dietary antioxidants, which help to prevent neuronal diseases, cardiovascular illnesses, cancer, diabetes, inflammation, and many such others diseases. Ability of anthocyanins to counter oxidants makes them atherosclerosis fighters. Therefore, anthocyanin-rich foods may help to boost overall health by offering an array of nutrients. However, the incorporation of anthocyanins into food and medical products is a challenging task due to their low stability toward environmental conditions during processing and storage. Encapsulation seems to be an efficient way to introduce such compounds into these products. Encapsulating agents act as a protector coat against ambient adverse conditions such as light, humidity, and oxygen. Encapsulated bioactive compounds are easier to handle and offer improved stability. The main objective of this review is to explore health benefits of anthocyanins and their extraction, characterization, encapsulation, and delivery.

  8. Effect of calcium on strawberry fruit flavonid gene expression and anthocyanins accumulation

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Strawberry fruit contain phenolic compounds such as anthocyanins, which have beneficial effects against oxidative stress mediated diseases. Two diploid strawberry (Fragaria vesca) inbred lines, Ruegen F7-4 (red fruit) and YW5AF7 (yellow fruit) were used to study the regulation of anthocyanin biosynt...

  9. Anthocyanins and antioxidant activity in coloured waxy corn at different maturation stages

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Concentrations of anthocyanins, phenolic compounds and antioxidant activities in kernels of 20 genotypes of waxy corn were investigated at two maturation stages, namely milky and mature. The levels of anthocyanins increased throughout the development of each genotype of corn, while phenolic compound...

  10. Using gamma irradiation for the recovery of anthocyanins from grape pomace

    NASA Astrophysics Data System (ADS)

    Ayed, N.; Yu, H.-L.; Lacroix, M.

    2000-03-01

    This research investigated the effect of gamma irradiation from 0 to 9 kGy, packaging in air or under vacuum, or in combination with other treatments for enhancing anthocyanin extraction from grape pomace. Results indicate that the irradiation at 6 kGy and packaging in the presence of a low concentration of sodium metabisulfite yielded the highest value of anthocyanin extraction.

  11. Effects of Growth Temperature and Postharvest Cooling on Anthocyanin Profiles in Juvenile and Mature Brassica oleracea.

    PubMed

    Socquet-Juglard, Didier; Bennett, Alexandra A; Manns, David C; Mansfield, Anna Katharine; Robbins, Rebecca J; Collins, Thomas M; Griffiths, Phillip D

    2016-02-24

    The effects of growth temperatures on anthocyanin content and profile were tested on juvenile cabbage and kale plants. The effects of cold storage time were evaluated on both juvenile and mature plants. The anthocyanin content in juvenile plants ranged from 3.82 mg of cyanidin-3,5-diglucoside equivalent (Cy equiv)/g of dry matter (dm) at 25 °C to 10.00 mg of Cy equiv/g of dm at 16 °C, with up to 76% diacylated anthocyanins. Cold storage of juvenile plants decreased the total amount of anthocyanins but increased the diacylated anthocyanin content by 3-5%. In mature plants, cold storage reduced the total anthocyanin content from 22 to 12.23 mg/g after 5 weeks of storage in red cabbage, while the total anthocyanin content increased after 2 weeks of storage from 2.34 to 3.66 mg of Cy equiv/g of dm in kale without having any effect on acylation in either morphotype. The results obtained in this study will be useful for optimizing anthocyanin production.

  12. Small differences in temperature interact with solar radiation to alter anthocyanin in grapes

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Despite a century of research, we still lack a concrete, mechanistic understanding of solar radiation and temperature effects on anthocyanin accumulation and composition, crucial for red wine grapes. Our aim was to elucidate the mechanistic response to microclimate of anthocyanin metabolism in Viti...

  13. Is solar radiation a key to good red wine grape anthocyanin?

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Despite a century of research, we still lack a concrete, mechanistic understanding of solar radiation and temperature effects on anthocyanin accumulation and composition, crucial for red wine grapes. Our aim was to elucidate the mechanistic response to microclimate of anthocyanin metabolism in Viti...

  14. Functional role of anthocyanins in the leaves of Quintinia serrata A. Cunn.

    PubMed

    Gould, K S; Markham, K R; Smith, R H; Goris, J J

    2000-06-01

    The protective functions that have been ascribed to anthocyanins in leaves can be performed as effectively by a number of other compounds. The possibility that anthocyanins accumulate most abundantly in leaves deficient in other phytoprotective pigments has been tested. Pigment concentrations and their histological distribution were surveyed for a sample of 1000 leaves from a forest population of Quintinia serrata, which displays natural polymorphism in leaf colour. Eight leaf phenotypes were recognized according to their patterns of red coloration. Anthocyanins were observed in almost all combinations of every leaf tissue, but were most commonly located in the vacuoles of photosynthetic cells. Red leaves contained two anthocyanins (Cy-3-glc and Cy-3-gal), epicuticular flavones, epidermal flavonols, hydroxycinnamic acids, chlorophylls, and carotenoids. Green leaves lacked anthocyanins, but had otherwise similar pigment profiles. Foliar anthocyanin levels varied significantly between branches and among trees, but were not correlated to concentrations of other pigments. Anthocyanins were most abundant in older leaves on trees under canopies with south-facing gaps. These data indicate that anthocyanins are associated with photosynthesis, but do not serve an auxiliary phytoprotective role. They may serve to protect shade-adapted chloroplasts from brief exposure to high intensity sunflecks.

  15. Effects of Growth Temperature and Postharvest Cooling on Anthocyanin Profiles in Juvenile and Mature Brassica oleracea.

    PubMed

    Socquet-Juglard, Didier; Bennett, Alexandra A; Manns, David C; Mansfield, Anna Katharine; Robbins, Rebecca J; Collins, Thomas M; Griffiths, Phillip D

    2016-02-24

    The effects of growth temperatures on anthocyanin content and profile were tested on juvenile cabbage and kale plants. The effects of cold storage time were evaluated on both juvenile and mature plants. The anthocyanin content in juvenile plants ranged from 3.82 mg of cyanidin-3,5-diglucoside equivalent (Cy equiv)/g of dry matter (dm) at 25 °C to 10.00 mg of Cy equiv/g of dm at 16 °C, with up to 76% diacylated anthocyanins. Cold storage of juvenile plants decreased the total amount of anthocyanins but increased the diacylated anthocyanin content by 3-5%. In mature plants, cold storage reduced the total anthocyanin content from 22 to 12.23 mg/g after 5 weeks of storage in red cabbage, while the total anthocyanin content increased after 2 weeks of storage from 2.34 to 3.66 mg of Cy equiv/g of dm in kale without having any effect on acylation in either morphotype. The results obtained in this study will be useful for optimizing anthocyanin production. PMID:26828966

  16. ATRX represses alternative lengthening of telomeres.

    PubMed

    Napier, Christine E; Huschtscha, Lily I; Harvey, Adam; Bower, Kylie; Noble, Jane R; Hendrickson, Eric A; Reddel, Roger R

    2015-06-30

    The unlimited proliferation of cancer cells requires a mechanism to prevent telomere shortening. Alternative Lengthening of Telomeres (ALT) is an homologous recombination-mediated mechanism of telomere elongation used in tumors, including osteosarcomas, soft tissue sarcoma subtypes, and glial brain tumors. Mutations in the ATRX/DAXX chromatin remodeling complex have been reported in tumors and cell lines that use the ALT mechanism, suggesting that ATRX may be an ALT repressor. We show here that knockout or knockdown of ATRX in mortal cells or immortal telomerase-positive cells is insufficient to activate ALT. Notably, however, in SV40-transformed mortal fibroblasts ATRX loss results in either a significant increase in the proportion of cell lines activating ALT (instead of telomerase) or in a significant decrease in the time prior to ALT activation. These data indicate that loss of ATRX function cooperates with one or more as-yet unidentified genetic or epigenetic alterations to activate ALT. Moreover, transient ATRX expression in ALT-positive/ATRX-negative cells represses ALT activity. These data provide the first direct, functional evidence that ATRX represses ALT.

  17. Repression of gene expression by oxidative stress.

    PubMed Central

    Morel, Y; Barouki, R

    1999-01-01

    Gene expression is modulated by both physiological signals (hormones, cytokines, etc.) and environmental stimuli (physical parameters, xenobiotics, etc.). Oxidative stress appears to be a key pleiotropic modulator which may be involved in either pathway. Indeed, reactive oxygen species (ROS) have been described as second messengers for several growth factors and cytokines, but have also been shown to rise following cellular insults such as xenobiotic metabolism or enzymic deficiency. Extensive studies on the induction of stress-response genes by oxidative stress have been reported. In contrast, owing to the historical focus on gene induction, less attention has been paid to gene repression by ROS. However, a growing number of studies have shown that moderate (i.e. non-cytotoxic) oxidative stress specifically down-regulates the expression of various genes. In this review, we describe the alteration of several physiological functions resulting from oxidative-stress-mediated inhibition of gene transcription. We will then focus on the repressive oxidative modulation of various transcription factors elicited by ROS. PMID:10477257

  18. Laser Isotope Separation Employing Condensation Repression

    SciTech Connect

    Eerkens, Jeff W.; Miller, William H.

    2004-09-15

    Molecular laser isotope separation (MLIS) techniques using condensation repression (CR) harvesting are reviewed and compared with atomic vapor laser isotope separation (AVLIS), gaseous diffusion (DIF), ultracentrifuges (UCF), and electromagnetic separations (EMS). Two different CR-MLIS or CRISLA (Condensation Repression Isotope Separation by Laser Activation) approaches have been under investigation at the University of Missouri (MU), one involving supersonic super-cooled free jets and dimer formation, and the other subsonic cold-wall condensation. Both employ mixtures of an isotopomer (e.g. {sup i}QF{sub 6}) and a carrier gas, operated at low temperatures and pressures. Present theories of VT relaxation, dimerization, and condensation are found to be unsatisfactory to explain/predict experimental CRISLA results. They were replaced by fundamentally new models that allow ab-initio calculation of isotope enrichments and predictions of condensation parameters for laser-excited and non-excited vapors which are in good agreement with experiment. Because of supersonic speeds, throughputs for free-jet CRISLA are a thousand times higher than cold-wall CRISLA schemes, and thus preferred for large-quantity Uranium enrichments. For small-quantity separations of (radioactive) medical isotopes, the simpler coldwall CRISLA method may be adequate.

  19. Repression of somatic cell fate in the germline.

    PubMed

    Robert, Valérie J; Garvis, Steve; Palladino, Francesca

    2015-10-01

    Germ cells must transmit genetic information across generations, and produce gametes while also maintaining the potential to form all cell types after fertilization. Preventing the activation of somatic programs is, therefore, crucial to the maintenance of germ cell identity. Studies in Caenorhabditis elegans, Drosophila melanogaster, and mouse have revealed both similarities and differences in how somatic gene expression is repressed in germ cells, thereby preventing their conversion into somatic tissues. This review will focus on recent developments in our understanding of how global or gene-specific transcriptional repression, chromatin regulation, and translational repression operate in the germline to maintain germ cell identity and repress somatic differentiation programs. PMID:26043973

  20. Calf thymus DNA-binding ability study of anthocyanins from purple sweet potatoes ( Ipomoea batatas L.).

    PubMed

    Wang, Dan; Wang, Xirui; Zhang, Chao; Ma, Yue; Zhao, Xiaoyan

    2011-07-13

    A total of 10 anthocyanin compounds were identified from five purple sweet potato ( Ipomoea batatas L.) varieties, Qunzi, Zishu038, Ji18, Jingshu6, and Ziluolan, by high-performance liquid chromatography-tandem mass spectrometry (HPLC-MS/MS) to assess their calf thymus DNA-binding ability in vitro. The interaction between anthocyanins and calf thymus DNA in Tris-HCl buffer solution (pH 6.9) was evaluated by fluorescence spectroscopy. Using ethidium bromide (EB) as a fluorescence probe, fluorescence quenching of the emission peak was seen in the DNA-EB system when anthocyanins were added, indicating that the anthocyanins bound with DNA. The acylated groups influenced the ability of the interaction with DNA. Anthocyanins from purple sweet potato with more acylated groups in sorphorose have a stronger binding ability with DNA.

  1. Calf thymus DNA-binding ability study of anthocyanins from purple sweet potatoes ( Ipomoea batatas L.).

    PubMed

    Wang, Dan; Wang, Xirui; Zhang, Chao; Ma, Yue; Zhao, Xiaoyan

    2011-07-13

    A total of 10 anthocyanin compounds were identified from five purple sweet potato ( Ipomoea batatas L.) varieties, Qunzi, Zishu038, Ji18, Jingshu6, and Ziluolan, by high-performance liquid chromatography-tandem mass spectrometry (HPLC-MS/MS) to assess their calf thymus DNA-binding ability in vitro. The interaction between anthocyanins and calf thymus DNA in Tris-HCl buffer solution (pH 6.9) was evaluated by fluorescence spectroscopy. Using ethidium bromide (EB) as a fluorescence probe, fluorescence quenching of the emission peak was seen in the DNA-EB system when anthocyanins were added, indicating that the anthocyanins bound with DNA. The acylated groups influenced the ability of the interaction with DNA. Anthocyanins from purple sweet potato with more acylated groups in sorphorose have a stronger binding ability with DNA. PMID:21678894

  2. Anthocyanin Profile in Berries of Wild and Cultivated Vaccinium spp. along Altitudinal Gradients in the Alps.

    PubMed

    Zoratti, Laura; Jaakola, Laura; Häggman, Hely; Giongo, Lara

    2015-10-01

    Vaccinium spp. berries provide some of the best natural sources of anthocyanins. In the wild bilberry (Vaccinium myrtillus L.), a clear increasing trend in anthocyanin biosynthesis has been reported toward northern latitudes of Europe, but studies related to altitude have given contradictory results. The present study focused on the anthocyanin composition in wild bilberries and highbush blueberry (Vaccinium corymbosum L. cv. Brigitta Blue) growing along altitudinal gradients in the Alps of northern Italy. Our results indicate an increasing accumulation of anthocyanins in bilberries along an altitudinal gradient of about 650 m. The accumulation was due to a significant increase in delphinidin and malvidin glycosides, whereas the accumulation of cyanidin and peonidin glycosides was not affected by altitude. Seasonal differences, especially temperature, had a major influence on the accumulation of anthocyanins in blueberries. PMID:26373665

  3. Anthocyanins from flowers of the orchids Dracula chimaera and D. cordobae.

    PubMed

    Fossen, Torgils; Øvstedal, Dag Olav

    2003-08-01

    The main anthocyanins from flowers of the orchids Dracula chimaera and D. cordobae were isolated from a purified methanolic extract by preparative HPLC. Their structures were determined to be cyanidin 3-O-(6"-O-malonyl-beta-glucopyranoside), cyanidin 3-O-(6"-O-alpha-rhamnopyranosyl-beta-glucopyranoside), cyanidin 3-O-beta-glucopyranoside, peonidin 3-O-(6"-O-alpha-rhamnopyranosyl-beta-glucopyranoside) and peonidin 3-O-(6"-O-malonyl-beta-glucopyranoside). The structure determinations were mainly based on extensive use of 2D and 1D NMR spectroscopy, UV-vis spectroscopy and MS. The anthocyanin contents of species belonging to the subtribe Pleurothallidinae including genus Dracula Luer (Orchidaceae) have previously not been determined. The high content of anthocyanin rutinosides found in D. chimaera and D. cordobae (78 and 28% of the total anthocyanin content, respectively) differs from previously analysed orchid species, in which glucose is found as the only anthocyanin sugar moiety.

  4. Carbohydrate accumulation may be the proximate trigger of anthocyanin biosynthesis under autumn conditions in Begonia semperflorens.

    PubMed

    Zhang, K M; Li, Z; Li, Y; Li, Y H; Kong, D Z; Wu, R H

    2013-11-01

    Many plant leaves appear red in the autumn, and many papers have focused on the environmental factors and role of anthocyanin in this process. However few papers have examined the substances that are induced during this process. We hypothesised that excess sugar accumulation directly induces anthocyanin accumulation under autumn conditions. Using two methods (restricting phloem movement and exogenous sucrose feeding), we found that both surplus photosynthate and exogenous sucrose could induce anthocyanin biosynthesis, corresponding to up-regulation of several enzymes involved in anthocyanin biosynthesis (phenylalanine ammonia lyase, chalcone isomerase, dihydroflavonol 4-reductase and flavonoid 3-O-glucosyl transferase) and in transport (glutathione S-transferase). Our results suggest that excess carbohydrate may be the proximate trigger for induction of anthocyanin biosynthesis in autumn, but only when carbohydrates are accumulated for storage.

  5. Accelerated, microwave-assisted, and conventional solvent extraction methods affect anthocyanin composition from colored grains.

    PubMed

    Abdel-Aal, El-Sayed M; Akhtar, Humayoun; Rabalski, Iwona; Bryan, Michael

    2014-02-01

    Anthocyanins are important dietary components with diverse positive functions in human health. This study investigates effects of accelerated solvent extraction (ASE) and microwave-assisted extraction (MAE) on anthocyanin composition and extraction efficiency from blue wheat, purple corn, and black rice in comparison with the commonly used solvent extraction (CSE). Factorial experimental design was employed to study effects of ASE and MAE variables, and anthocyanin extracts were analyzed by spectrophotometry, high-performance liquid chromatography-diode array detector (DAD), and liquid chromatography-mass spectrometry chromatography. The extraction efficiency of ASE and MAE was comparable with CSE at the optimal conditions. The greatest extraction by ASE was achieved at 50 °C, 2500 psi, 10 min using 5 cycles, and 100% flush. For MAE, a combination of 70 °C, 300 W, and 10 min in MAE was the most effective in extracting anthocyanins from blue wheat and purple corn compared with 50 °C, 1200 W, and 20 min for black rice. The anthocyanin composition of grain extracts was influenced by the extraction method. The ASE extraction method seems to be more appropriate in extracting anthocyanins from the colored grains as being comparable with the CSE method based on changes in anthocyanin composition. The method caused lower structural changes in anthocaynins compared with the MAE method. Changes in blue wheat anthocyanins were lower in comparison with purple corn or black rice perhaps due to the absence of acylated anthocyanin compounds in blue wheat. The results show significant differences in anthocyanins among the 3 extraction methods, which indicate a need to standardize a method for valid comparisons among studies and for quality assurance purposes. PMID:24547694

  6. Accelerated, microwave-assisted, and conventional solvent extraction methods affect anthocyanin composition from colored grains.

    PubMed

    Abdel-Aal, El-Sayed M; Akhtar, Humayoun; Rabalski, Iwona; Bryan, Michael

    2014-02-01

    Anthocyanins are important dietary components with diverse positive functions in human health. This study investigates effects of accelerated solvent extraction (ASE) and microwave-assisted extraction (MAE) on anthocyanin composition and extraction efficiency from blue wheat, purple corn, and black rice in comparison with the commonly used solvent extraction (CSE). Factorial experimental design was employed to study effects of ASE and MAE variables, and anthocyanin extracts were analyzed by spectrophotometry, high-performance liquid chromatography-diode array detector (DAD), and liquid chromatography-mass spectrometry chromatography. The extraction efficiency of ASE and MAE was comparable with CSE at the optimal conditions. The greatest extraction by ASE was achieved at 50 °C, 2500 psi, 10 min using 5 cycles, and 100% flush. For MAE, a combination of 70 °C, 300 W, and 10 min in MAE was the most effective in extracting anthocyanins from blue wheat and purple corn compared with 50 °C, 1200 W, and 20 min for black rice. The anthocyanin composition of grain extracts was influenced by the extraction method. The ASE extraction method seems to be more appropriate in extracting anthocyanins from the colored grains as being comparable with the CSE method based on changes in anthocyanin composition. The method caused lower structural changes in anthocaynins compared with the MAE method. Changes in blue wheat anthocyanins were lower in comparison with purple corn or black rice perhaps due to the absence of acylated anthocyanin compounds in blue wheat. The results show significant differences in anthocyanins among the 3 extraction methods, which indicate a need to standardize a method for valid comparisons among studies and for quality assurance purposes.

  7. Optimization of microwave-assisted extraction of anthocyanins from mulberry and identification of anthocyanins in extract using HPLC-ESI-MS.

    PubMed

    Zou, Tangbin; Wang, Dongliang; Guo, Honghui; Zhu, Yanna; Luo, Xiaoqin; Liu, Fengqiong; Ling, Wenhua

    2012-01-01

    Anthocyanins are naturally occurring compounds that impart color to fruits, vegetables, and plants. This study aims to optimize the microwave-assisted extraction (MAE) conditions of anthocyanins from mulberry (M. atropurpurea Roxb.) using response surface methodology (RSM). A Box-Behnken experiment was employed in this regard. Methanol concentration, microwave power, and extraction time were chosen as independent variables. The optimized conditions of MAE were as follows: 59.6% acidified methanol, 425 W power, 25 (v/w) liquid-to-solid ratio, and 132 s time. Under these conditions, 54.72 mg anthocyanins were obtained from 1.0 g mulberry powder. Furthermore, 8 anthocyanins were identified by high-performance liquid chromatography-electrospray ionization-mass spectrometry (HPLC-ESI-MS) in mulberry extract. The results showed that cyanidin-3-glucoside and cyanidin-3-rutinoside are the major anthocyanins in mulberry. In addition, in comparison with conventional extraction, MAE is more rapid and efficient for extracting anthocyanins from mulberry. PMID:22260102

  8. SAGA complex components and acetate repression in Aspergillus nidulans.

    PubMed

    Georgakopoulos, Paraskevi; Lockington, Robin A; Kelly, Joan M

    2012-11-01

    Alongside the well-established carbon catabolite repression by glucose and other sugars, acetate causes repression in Aspergillus nidulans. Mutations in creA, encoding the transcriptional repressor involved in glucose repression, also affect acetate repression, but mutations in creB or creC, encoding components of a deubiquitination system, do not. To understand the effects of acetate, we used a mutational screen that was similar to screens that uncovered mutations in creA, creB, and creC, except that glucose was replaced by acetate to identify mutations that were affected for repression by acetate but not by glucose. We uncovered mutations in acdX, homologous to the yeast SAGA component gene SPT8, which in growth tests showed derepression for acetate repression but not for glucose repression. We also made mutations in sptC, homologous to the yeast SAGA component gene SPT3, which showed a similar phenotype. We found that acetate repression is complex, and analysis of facA mutations (lacking acetyl CoA synthetase) indicates that acetate metabolism is required for repression of some systems (proline metabolism) but not for others (acetamide metabolism). Although plate tests indicated that acdX- and sptC-null mutations led to derepressed alcohol dehydrogenase activity, reverse-transcription quantitative real-time polymerase chain reaction showed no derepression of alcA or aldA but rather elevated induced levels. Our results indicate that acetate repression is due to repression via CreA together with metabolic changes rather than due to an independent regulatory control mechanism.

  9. Pyrimidine biosynthetic enzymes of Salmonella typhimurium, repressed specifically by growth in the presence of cytidine.

    PubMed Central

    Kelln, R A; Kinahan, J J; Foltermann, K F; O'Donovan, G A

    1975-01-01

    The repressive effects of exogenous cytidine on growing cells was examined in a specially constructed strain in which the pool sizes of endogenous uridine 5'-diphosphate and uridine 5'-triphosphate cannot be varied by the addition of uracil and/or uridine to the medium. Five enzymes of the pyrimidine biosynthetic pathway and one enzyme of the arginine biosynthetic pathway were assayed from cells grown under a variety of conditions. Cytidine repressed the synthesis of dihydroorotase (encoded by pyrC), dihydroorotate dehydrogenase (encoded by pyrD), and ornithine transcarbamylase (encoded by argI). Moreover, aspartate transcarbamylase (encoded by pyrB) became further derepressed upon cytidine addition, whereas no change occurred in the levels of the last two enzymes (encoded by pyrE and pyrF) of the pyrimidine pathway. Quantitative nucleotide pool determinations have provided evidence that any individual ribo- or deoxyribonucleoside mono-, di-, or triphosphate of cytosine or uracil is not a repressing metabolite for the pyrimidine biosynthetic enzymes. Other nucleotide derivatives or ratios must be considered. PMID:1102530

  10. Not4-dependent translational repression is important for cellular protein homeostasis in yeast

    PubMed Central

    Preissler, Steffen; Reuther, Julia; Koch, Miriam; Scior, Annika; Bruderek, Michael; Frickey, Tancred; Deuerling, Elke

    2015-01-01

    Translation of aberrant or problematic mRNAs can cause ribosome stalling which leads to the production of truncated or defective proteins. Therefore, cells evolved cotranslational quality control mechanisms that eliminate these transcripts and target arrested nascent polypeptides for proteasomal degradation. Here we show that Not4, which is part of the multifunctional Ccr4–Not complex in yeast, associates with polysomes and contributes to the negative regulation of protein synthesis. Not4 is involved in translational repression of transcripts that cause transient ribosome stalling. The absence of Not4 affected global translational repression upon nutrient withdrawal, enhanced the expression of arrested nascent polypeptides and caused constitutive protein folding stress and aggregation. Similar defects were observed in cells with impaired mRNA decapping protein function and in cells lacking the mRNA decapping activator and translational repressor Dhh1. The results suggest a role for Not4 together with components of the decapping machinery in the regulation of protein expression on the mRNA level and emphasize the importance of translational repression for the maintenance of proteome integrity. PMID:25971775

  11. Mir-29 repression in bladder outlet obstruction contributes to matrix remodeling and altered stiffness.

    PubMed

    Ekman, Mari; Bhattachariya, Anirban; Dahan, Diana; Uvelius, Bengt; Albinsson, Sebastian; Swärd, Karl

    2013-01-01

    Recent work has uncovered a role of the microRNA (miRNA) miR-29 in remodeling of the extracellular matrix. Partial bladder outlet obstruction is a prevalent condition in older men with prostate enlargement that leads to matrix synthesis in the lower urinary tract and increases bladder stiffness. Here we tested the hypothesis that miR-29 is repressed in the bladder in outlet obstruction and that this has an impact on protein synthesis and matrix remodeling leading to increased bladder stiffness. c-Myc, NF-κB and SMAD3, all of which repress miR-29, were activated in the rat detrusor following partial bladder outlet obstruction but at different times. c-Myc and NF-κB activation occurred early after obstruction, and SMAD3 phosphorylation increased later, with a significant elevation at 6 weeks. c-Myc, NF-κB and SMAD3 activation, respectively, correlated with repression of miR-29b and miR-29c at 10 days of obstruction and with repression of miR-29c at 6 weeks. An mRNA microarray analysis showed that the reduction of miR-29 following outlet obstruction was associated with increased levels of miR-29 target mRNAs, including mRNAs for tropoelastin, the matricellular protein Sparc and collagen IV. Outlet obstruction increased protein levels of eight out of eight examined miR-29 targets, including tropoelastin and Sparc. Transfection of human bladder smooth muscle cells with antimiR-29c and miR-29c mimic caused reciprocal changes in target protein levels in vitro. Tamoxifen inducible and smooth muscle-specific deletion of Dicer in mice reduced miR-29 expression and increased tropoelastin and the thickness of the basal lamina surrounding smooth muscle cells in the bladder. It also increased detrusor stiffness independent of outlet obstruction. Taken together, our study supports a model where the combined repressive influences of c-Myc, NF-κB and SMAD3 reduce miR-29 in bladder outlet obstruction, and where the resulting drop in miR-29 contributes to matrix remodeling and

  12. Mir-29 Repression in Bladder Outlet Obstruction Contributes to Matrix Remodeling and Altered Stiffness

    PubMed Central

    Ekman, Mari; Bhattachariya, Anirban; Dahan, Diana; Uvelius, Bengt; Albinsson, Sebastian; Swärd, Karl

    2013-01-01

    Recent work has uncovered a role of the microRNA (miRNA) miR-29 in remodeling of the extracellular matrix. Partial bladder outlet obstruction is a prevalent condition in older men with prostate enlargement that leads to matrix synthesis in the lower urinary tract and increases bladder stiffness. Here we tested the hypothesis that miR-29 is repressed in the bladder in outlet obstruction and that this has an impact on protein synthesis and matrix remodeling leading to increased bladder stiffness. c-Myc, NF-κB and SMAD3, all of which repress miR-29, were activated in the rat detrusor following partial bladder outlet obstruction but at different times. c-Myc and NF-κB activation occurred early after obstruction, and SMAD3 phosphorylation increased later, with a significant elevation at 6 weeks. c-Myc, NF-κB and SMAD3 activation, respectively, correlated with repression of miR-29b and miR-29c at 10 days of obstruction and with repression of miR-29c at 6 weeks. An mRNA microarray analysis showed that the reduction of miR-29 following outlet obstruction was associated with increased levels of miR-29 target mRNAs, including mRNAs for tropoelastin, the matricellular protein Sparc and collagen IV. Outlet obstruction increased protein levels of eight out of eight examined miR-29 targets, including tropoelastin and Sparc. Transfection of human bladder smooth muscle cells with antimiR-29c and miR-29c mimic caused reciprocal changes in target protein levels in vitro. Tamoxifen inducible and smooth muscle-specific deletion of Dicer in mice reduced miR-29 expression and increased tropoelastin and the thickness of the basal lamina surrounding smooth muscle cells in the bladder. It also increased detrusor stiffness independent of outlet obstruction. Taken together, our study supports a model where the combined repressive influences of c-Myc, NF-κB and SMAD3 reduce miR-29 in bladder outlet obstruction, and where the resulting drop in miR-29 contributes to matrix remodeling and

  13. Plant callus: mechanisms of induction and repression.

    PubMed

    Ikeuchi, Momoko; Sugimoto, Keiko; Iwase, Akira

    2013-09-01

    Plants develop unorganized cell masses like callus and tumors in response to various biotic and abiotic stimuli. Since the historical discovery that the combination of two growth-promoting hormones, auxin and cytokinin, induces callus from plant explants in vitro, this experimental system has been used extensively in both basic research and horticultural applications. The molecular basis of callus formation has long been obscure, but we are finally beginning to understand how unscheduled cell proliferation is suppressed during normal plant development and how genetic and environmental cues override these repressions to induce callus formation. In this review, we will first provide a brief overview of callus development in nature and in vitro and then describe our current knowledge of genetic and epigenetic mechanisms underlying callus formation. PMID:24076977

  14. Pharmacological repression of PPARγ promotes osteogenesis.

    PubMed

    Marciano, David P; Kuruvilla, Dana S; Boregowda, Siddaraju V; Asteian, Alice; Hughes, Travis S; Garcia-Ordonez, Ruben; Corzo, Cesar A; Khan, Tanya M; Novick, Scott J; Park, HaJeung; Kojetin, Douglas J; Phinney, Donald G; Bruning, John B; Kamenecka, Theodore M; Griffin, Patrick R

    2015-06-12

    The nuclear receptor peroxisome proliferator-activated receptor gamma (PPARγ) is the master regulator of adipogenesis and the pharmacological target of the thiazolidinedione (TZD) class of insulin sensitizers. Activation of PPARγ by TZDs promotes adipogenesis at the expense of osteoblast formation, contributing to their associated adverse effects on bone. Recently, we reported the development of PPARγ antagonist SR1664, designed to block the obesity-induced phosphorylation of serine 273 (S273) in the absence of classical agonism, to derive insulin-sensitizing efficacy with improved therapeutic index. Here we identify the structural mechanism by which SR1664 actively antagonizes PPARγ, and extend these findings to develop the inverse agonist SR2595. Treatment of isolated bone marrow-derived mesenchymal stem cells with SR2595 promotes induction of osteogenic differentiation. Together these results identify the structural determinants of ligand-mediated PPARγ repression, and suggest a therapeutic approach to promote bone formation.

  15. Pharmacological Repression of PPARγ Promotes Osteogenesis

    PubMed Central

    Marciano, David P.; Kuruvilla, Dana S.; Boregowda, Siddaraju V.; Asteian, Alice; Hughes, Travis S.; Garcia-Ordonez, Ruben; Corzo, Cesar A.; Khan, Tanya M.; Novick, Scott J.; Park, HaJeung; Kojetin, Douglas J.; Phinney, Donald G.; Bruning, John B.; Kamenecka, Theodore M.; Griffin, Patrick R.

    2015-01-01

    The nuclear receptor peroxisome proliferator-activated receptor gamma (PPARγ) is the master regulator of adipogenesis and the pharmacological target of the thiazolidinedione (TZD) class of insulin sensitizers. Activation of PPARγ by TZDs promotes adipogenesis at the expense of osteoblast formation, contributing to their associated adverse effects on bone. Recently we reported the development of PPARγ antagonist SR1664, designed to block the obesity induced phosphorylation of serine 273 (S273) in the absence of classical agonism, to derive insulin sensitizing efficacy with improved therapeutic index. Here we identify the structural mechanism by which SR1664 actively antagonizes PPARγ, and extend these findings to develop the inverse agonist SR2595. Treatment of isolated bone marrow derived mesenchymal stem cells (MSCs) with SR2595 promotes induction of osteogenic differentiation. Together these results identify the structural determinants of ligand mediated PPARγ repression, and suggest a therapeutic approach to promote bone formation. PMID:26068133

  16. Hypnotizability as a Function of Repression, Adaptive Regression, and Mood

    ERIC Educational Resources Information Center

    Silver, Maurice Joseph

    1974-01-01

    Forty male undergraduates were assessed in a personality assessment session and a hypnosis session. The personality traits studied were repressive style and adaptive regression, while the transitory variable was mood prior to hypnosis. Hypnotizability was a significant interactive function of repressive style and mood, but not of adaptive…

  17. Dream Recall And Repression: Evidence For An Alternative Hypothesis

    ERIC Educational Resources Information Center

    Cohen, David B.; Wolfe, Gary

    1973-01-01

    An "Inner-rejectant" life style committed to repressing dreams has been described in terms of external locus of control, field dependence, and "poor inner life." However, in empirical studies reported here, results do not provide strong support for the (repression) formulation. The results suggest a distinction between life-style variables related…

  18. Estimation of Anthocyanin Content of Berries by NIR Method

    NASA Astrophysics Data System (ADS)

    Zsivanovits, G.; Ludneva, D.; Iliev, A.

    2010-01-01

    Anthocyanin contents of fruits were estimated by VIS spectrophotometer and compared with spectra measured by NIR spectrophotometer (600-1100 nm step 10 nm). The aim was to find a relationship between NIR method and traditional spectrophotometric method. The testing protocol, using NIR, is easier, faster and non-destructive. NIR spectra were prepared in pairs, reflectance and transmittance. A modular spectrocomputer, realized on the basis of a monochromator and peripherals Bentham Instruments Ltd (GB) and a photometric camera created at Canning Research Institute, were used. An important feature of this camera is the possibility offered for a simultaneous measurement of both transmittance and reflectance with geometry patterns T0/180 and R0/45. The collected spectra were analyzed by CAMO Unscrambler 9.1 software, with PCA, PLS, PCR methods. Based on the analyzed spectra quality and quantity sensitive calibrations were prepared. The results showed that the NIR method allows measuring of the total anthocyanin content in fresh berry fruits or processed products without destroying them.

  19. Estimation of Anthocyanin Content of Berries by NIR Method

    SciTech Connect

    Zsivanovits, G.; Ludneva, D.; Iliev, A.

    2010-01-21

    Anthocyanin contents of fruits were estimated by VIS spectrophotometer and compared with spectra measured by NIR spectrophotometer (600-1100 nm step 10 nm). The aim was to find a relationship between NIR method and traditional spectrophotometric method. The testing protocol, using NIR, is easier, faster and non-destructive. NIR spectra were prepared in pairs, reflectance and transmittance. A modular spectrocomputer, realized on the basis of a monochromator and peripherals Bentham Instruments Ltd (GB) and a photometric camera created at Canning Research Institute, were used. An important feature of this camera is the possibility offered for a simultaneous measurement of both transmittance and reflectance with geometry patterns T0/180 and R0/45. The collected spectra were analyzed by CAMO Unscrambler 9.1 software, with PCA, PLS, PCR methods. Based on the analyzed spectra quality and quantity sensitive calibrations were prepared. The results showed that the NIR method allows measuring of the total anthocyanin content in fresh berry fruits or processed products without destroying them.

  20. Gastrointestinal uptake of nasunin, acylated anthocyanin in eggplant.

    PubMed

    Ichiyanagi, Takashi; Terahara, Norihiko; Rahman, M Mamunur; Konishi, Tetsuya

    2006-07-26

    We previously showed that nasunin, acylated anthocyanins in eggplant peel, comprises two isomers, cis-nasunin and trans-nasunin. In this study, gastrointestinal absorption of cis- and trans-nasunins was studied in rats. Orally administered nasunins were quickly absorbed in their original acylated forms and maximally appeared in blood plasma after 15 min. When the maximum plasma concentration and area under the plasma concentration curve were normalized by orally administered dose (micromoles per kilogram), there was no significant difference in the uptake efficiency between two isomers and both exhibited a plasma level almost identical to that of delphinidin 3-O-beta-D-glucopyranoside. However, metabolites such as 4'-O-methyl analogues and extended glucuronides which were observed for delphinidin 3-O-beta-D-glucopyranoside and cyanidin 3-O-beta-D-glucopyranoside metabolisms were not detected in urine or blood plasma. Moreover, deacylated and glycolytic products of nasunins such as delphinidin 3-O-beta-D-glucopyranoside or delphinidin (aglycone) were also not detected in blood plasma even after oral administration for 8 h. These results indicated that nasunins were absorbed in their original acylated forms and exhibit a bioavailability almost identical to that of nonacylated anthocyanins. PMID:16848510

  1. Multiple Poliovirus Proteins Repress Cytoplasmic RNA Granules

    PubMed Central

    Dougherty, Jonathan D.; Tsai, Wei-Chih; Lloyd, Richard E.

    2015-01-01

    We have previously shown that poliovirus (PV) infection induces stress granule (SG) formation early in infection and then inhibits the formation of SG and disperses processing bodies (PBs) by the mid-phase of infection. Loss of SG was linked to cleavage of G3BP1 by viral 3C proteinase (3Cpro), however dispersal of PBs was not strongly linked to cleavage of specific factors by viral proteinases, suggesting other viral proteins may play roles in inhibition of SG or PB formation. Here we have screened all viral proteins for roles in inducing or inhibiting the formation of RNA granules by creating fusions with mCherry and expressing them individually in cells. Expression of viral proteins separately revealed that the capsid region P1, 2Apro, 3A, 3Cpro, the protease precursor 3CD and 3D polymerase all affect RNA granules to varying extents, whereas 2BC does not. 2Apro, which cleaves eIF4GI, induced SGs as expected, and entered novel foci containing the SG nucleating protein G3BP1. Of the two forms of G3BP, only G3BP1 is cleaved by a virus proteinase, 3Cpro, whereas G3BP2 is not cleaved by 3Cpro or 2Apro. Surprisingly, 3CD, which contains proteinase activity, differentially repressed PBs but not SGs. Further, both 2Apro and 3Cpro expression dispersed PBs, however molecular targets were different since PB dispersal due to 2Apro and heat shock protein (Hsp)90 inhibition but not 3Cpro, could be rescued by application of oxidative stress to cells. The data indicate that PV repression of SGs and PBs is multifactorial, though protease function is dominant. PMID:26610553

  2. Huntingtin facilitates polycomb repressive complex 2

    PubMed Central

    Seong, Ihn Sik; Woda, Juliana M.; Song, Ji-Joon; Lloret, Alejandro; Abeyrathne, Priyanka D.; Woo, Caroline J.; Gregory, Gillian; Lee, Jong-Min; Wheeler, Vanessa C.; Walz, Thomas; Kingston, Robert E.; Gusella, James F.; Conlon, Ronald A.; MacDonald, Marcy E.

    2010-01-01

    Huntington's disease (HD) is caused by expansion of the polymorphic polyglutamine segment in the huntingtin protein. Full-length huntingtin is thought to be a predominant HEAT repeat α-solenoid, implying a role as a facilitator of macromolecular complexes. Here we have investigated huntingtin's domain structure and potential intersection with epigenetic silencer polycomb repressive complex 2 (PRC2), suggested by shared embryonic deficiency phenotypes. Analysis of a set of full-length recombinant huntingtins, with different polyglutamine regions, demonstrated dramatic conformational flexibility, with an accessible hinge separating two large α-helical domains. Moreover, embryos lacking huntingtin exhibited impaired PRC2 regulation of Hox gene expression, trophoblast giant cell differentiation, paternal X chromosome inactivation and histone H3K27 tri-methylation, while full-length endogenous nuclear huntingtin in wild-type embryoid bodies (EBs) was associated with PRC2 subunits and was detected with trimethylated histone H3K27 at Hoxb9. Supporting a direct stimulatory role, full-length recombinant huntingtin significantly increased the histone H3K27 tri-methylase activity of reconstituted PRC2 in vitro, and structure–function analysis demonstrated that the polyglutamine region augmented full-length huntingtin PRC2 stimulation, both in HdhQ111 EBs and in vitro, with reconstituted PRC2. Knowledge of full-length huntingtin's α-helical organization and role as a facilitator of the multi-subunit PRC2 complex provides a novel starting point for studying PRC2 regulation, implicates this chromatin repressive complex in a neurodegenerative disorder and sets the stage for further study of huntingtin's molecular function and the impact of its modulatory polyglutamine region. PMID:19933700

  3. Polycomb repressive complex 1 controls uterine decidualization

    PubMed Central

    Bian, Fenghua; Gao, Fei; Kartashov, Andrey V.; Jegga, Anil G.; Barski, Artem; Das, Sanjoy K.

    2016-01-01

    Uterine stromal cell decidualization is an essential part of the reproductive process. Decidual tissue development requires a highly regulated control of the extracellular tissue remodeling; however the mechanism of this regulation remains unknown. Through systematic expression studies, we detected that Cbx4/2, Rybp, and Ring1B [components of polycomb repressive complex 1 (PRC1)] are predominantly utilized in antimesometrial decidualization with polyploidy. Immunofluorescence analyses revealed that PRC1 members are co-localized with its functional histone modifier H2AK119ub1 (mono ubiquitination of histone-H2A at lysine-119) in polyploid cell. A potent small-molecule inhibitor of Ring1A/B E3-ubiquitin ligase or siRNA-mediated suppression of Cbx4 caused inhibition of H2AK119ub1, in conjunction with perturbation of decidualization and polyploidy development, suggesting a role for Cbx4/Ring1B-containing PRC1 in these processes. Analyses of genetic signatures by RNA-seq studies showed that the inhibition of PRC1 function affects 238 genes (154 up and 84 down) during decidualization. Functional enrichment analyses identified that about 38% genes primarily involved in extracellular processes are specifically targeted by PRC1. Furthermore, ~15% of upregulated genes exhibited a significant overlap with the upregulated Bmp2 null-induced genes in mice. Overall, Cbx4/Ring1B-containing PRC1 controls decidualization via regulation of extracellular gene remodeling functions and sheds new insights into underlying molecular mechanism(s) through transcriptional repression regulation. PMID:27181215

  4. Anthocyanins protected hearts against ischemic injury by reducing MMP-2 activity via Akt/P38 pathways

    PubMed Central

    Hao, Jie; Du, Hong; Li, Weiwei; Liu, Fan; Lu, Jingchao; Yang, Xiuchun; Cui, Wei

    2016-01-01

    Growing evidences suggest that there are close associations between anthocyanins and cardiac protection. However, little is known about the detailed roles of anthocyanins in regulating extracellular matrix (ECM) remodeling. Incubation of primary cultured fibroblasts with anthocyanins reduced both intracellular collagen expression and extracellular collagen secretion. Down-regulation of collagen production was also shown in infarcted cardiac tissues after permanent coronary artery ligation in mice treated with anthocyanins. The phosphorylation levels of Akt and/or P-38 were significantly increased by anthocyanins supplementation in primary cultured fibroblasts. Gelatin zymography analysis of matrix metalloproteinase-2 (MMP-2) activity in conditioned medium collected from fibroblasts demonstrated that anthocyanins treatment significantly reduced MMP-2 activity. These results demonstrated that anthocyanins play a role in mediating myocardial ECM remodeling and that the Akt/P-38 pathways mediate these protective effects on hearts. PMID:27158396

  5. Influence of rutin and ascorbic acid in colour, plum anthocyanins and antioxidant capacity stability in model juices.

    PubMed

    Hernández-Herrero, J A; Frutos, M J

    2015-04-15

    Model juices at pH 3.7 were prepared with different combinations of ascorbic acid, rutin (quercetin 3-rutinoside) and concentrated anthocyanin extract of plums (cv. Black Gold). The anthocyanins in the concentrated extract were cyanidin 3-glucoside and cyanidin 3-rutinoside, in a proportion of 76% and 24% respectively. The model juices were stored during 17 weeks in darkness at 20 °C. The colour stability was improved by the presence of rutin and strongly damaged by the ascorbic acid. The fortification of anthocyanin model juices with ascorbic acid originated the degradation of most of anthocyanins. However, anthocyanins improved ascorbic acid stability during storage. The copigmentation of anthocyanin and rutin showed a beneficial effect on colour stability from the 5 weeks of storage. In model juices prepared exclusively with purified plum extract a high correlation (R(2)=0.881) between anthocyanins and antioxidant capacity was found. PMID:25466051

  6. Influence of rutin and ascorbic acid in colour, plum anthocyanins and antioxidant capacity stability in model juices.

    PubMed

    Hernández-Herrero, J A; Frutos, M J

    2015-04-15

    Model juices at pH 3.7 were prepared with different combinations of ascorbic acid, rutin (quercetin 3-rutinoside) and concentrated anthocyanin extract of plums (cv. Black Gold). The anthocyanins in the concentrated extract were cyanidin 3-glucoside and cyanidin 3-rutinoside, in a proportion of 76% and 24% respectively. The model juices were stored during 17 weeks in darkness at 20 °C. The colour stability was improved by the presence of rutin and strongly damaged by the ascorbic acid. The fortification of anthocyanin model juices with ascorbic acid originated the degradation of most of anthocyanins. However, anthocyanins improved ascorbic acid stability during storage. The copigmentation of anthocyanin and rutin showed a beneficial effect on colour stability from the 5 weeks of storage. In model juices prepared exclusively with purified plum extract a high correlation (R(2)=0.881) between anthocyanins and antioxidant capacity was found.

  7. Norepinephrine represses the expression of toxA and the siderophore genes in Pseudomonas aeruginosa.

    PubMed

    Li, Wang; Lyte, Mark; Freestone, Primrose P; Ajmal, Aziba; Colmer-Hamood, Jane A; Hamood, Abdul N

    2009-10-01

    Among the different extracellular virulence factors produced by Pseudomonas aeruginosa are exotoxin A (ETA) and the pyoverdine and pyochelin siderophores. Production of ETA and the siderophores requires the function of the iron-starvation sigma factor PvdS, the transcriptional activator RegA, and the AraC-activator PchR. Iron represses the production of ETA and the siderophores by repressing the expression of pvdS, regA, and pchR. PvdS regulates the expression of the ETA gene, toxA, regA, and the pyoverdine synthesis genes. The catecholamine norepinephrine enhances the growth of pathogenic bacteria by transferring iron from host-binding proteins. In this study, we elucidated the mechanism by which norepinephrine and other catecholamines induce P. aeruginosa growth. We also investigated whether norepinephrine regulates the expression of toxA and the siderophore genes, and the mechanism of this regulation. Norepinephrine enhanced the growth of P. aeruginosa by supplying iron from transferrin. This provision of iron repressed the expression of toxA, the pyoverdine genes pvdD and pvdE, and their regulators, pvdS, regA, and pchR, suggesting that norepinephrine accomplishes this repression through PvdS and PchR. Additionally, norepinephrine bypassed PvdS and supported the growth of a pvdS deletion mutant, indicating that norepinephrine transfers iron to P. aeruginosa independent of pyoverdine. Thus, norepinephrine apparently influences the pathogenesis of P. aeruginosa by affecting its pattern of growth and the production of virulence factors. PMID:19686346

  8. Anthocyanin Absorption and Metabolism by Human Intestinal Caco-2 Cells—A Review

    PubMed Central

    Kamiloglu, Senem; Capanoglu, Esra; Grootaert, Charlotte; Van Camp, John

    2015-01-01

    Anthocyanins from different plant sources have been shown to possess health beneficial effects against a number of chronic diseases. To obtain any influence in a specific tissue or organ, these bioactive compounds must be bioavailable, i.e., effectively absorbed from the gut into the circulation and transferred to the appropriate location within the body while still maintaining their bioactivity. One of the key factors affecting the bioavailability of anthocyanins is their transport through the gut epithelium. The Caco-2 cell line, a human intestinal epithelial cell model derived from a colon carcinoma, has been proven to be a good alternative to animal studies for predicting intestinal absorption of anthocyanins. Studies investigating anthocyanin absorption by Caco-2 cells report very low absorption of these compounds. However, the bioavailability of anthocyanins may be underestimated since the metabolites formed in the course of digestion could be responsible for the health benefits associated with anthocyanins. In this review, we critically discuss recent findings reported on the anthocyanin absorption and metabolism by human intestinal Caco-2 cells. PMID:26370977

  9. In planta anthocyanin degradation by a vacuolar class III peroxidase in Brunfelsia calycina flowers.

    PubMed

    Zipor, Gadi; Duarte, Patrícia; Carqueijeiro, Inês; Shahar, Liat; Ovadia, Rinat; Teper-Bamnolker, Paula; Eshel, Dani; Levin, Yishai; Doron-Faigenboim, Adi; Sottomayor, Mariana; Oren-Shamir, Michal

    2015-01-01

    In contrast to detailed knowledge regarding the biosynthesis of anthocyanins, the largest group of plant pigments, little is known about their in planta degradation. It has been suggested that anthocyanin degradation is enzymatically controlled and induced when beneficial to the plant. Here we investigated the enzymatic process in Brunfelsia calycina flowers, as they changed color from purple to white. We characterized the enzymatic process by which B. calycina protein extracts degrade anthocyanins. A candidate peroxidase was partially purified and characterized and its intracellular localization was determined. The transcript sequence of this peroxidase was fully identified. A basic peroxidase, BcPrx01, is responsible for the in planta degradation of anthocyanins in B. calycina flowers. BcPrx01 has the ability to degrade complex anthocyanins, it co-localizes with these pigments in the vacuoles of petals, and both the mRNA and protein levels of BcPrx01 are greatly induced parallel to the degradation of anthocyanins. Both isoelectric focusing (IEF) gel analysis and 3D structure prediction indicated that BcPrx01 is cationic. Identification of BcPrx01 is a significant breakthrough both in the understanding of anthocyanin catabolism in plants and in the field of peroxidases, where such a consistent relationship between expression levels, in planta subcellular localization and activity has seldom been demonstrated.

  10. Classification of fruits based on anthocyanin types and relevance to their health effects.

    PubMed

    Fang, Jim

    2015-01-01

    Anthocyanins are a group of water-soluble pigments that confer the blue, purple, and red color to many fruits. Anthocyanin-rich fruits can be divided into three groups based on the types of aglycones of their anthocyanins: pelargonidin group, cyanidin/peonidin group, and multiple anthocyanidins group. Some fruits contain a major anthocyanin type and can serve as useful research tools. Cyanidin glycosides and peonidin glycosides can be metabolically converted to each other by methylation and demethylation. Both cyanidin and peonidin glycosides can be metabolized to protocatechuic acid and vanillic acid. Pelargonidin-3-glucoside is metabolized to 4-hydroxybenoic acid. On the other hand, phenolic acid metabolites of delphinidin, malvidin, and petunidin glycosides are unstable and can be further fragmented into smaller molecules. A literature review indicates berries with higher cyanidin content, such as black raspberries, chokeberries, and bilberries are more likely to produce an antiinflammatory effect. This observation seems to be consistent with the hypothesis that one or more stable phenolic acid metabolites contribute to the antiinflammatory effects of anthocyanin-rich fruits. More studies are needed before we can conclude that fruits rich in cyanidin, peonidin, or pelargonidin glycosides have better antiinflammatory effects. Additionally, fruit polyphenols other than anthocyanins could contribute to their antiinflammatory effects. Furthermore, blueberries could exert their health effects with other mechanisms such as improving intestinal microbiota composition. In summary, this classification system can facilitate our understanding of the absorption and metabolic processes of anthocyanins and the health effects of different fruits.

  11. Low medium pH value enhances anthocyanin accumulation in Malus crabapple leaves.

    PubMed

    Zhang, Yanchen; Zhang, Jie; Song, Tingting; Li, Jinyan; Tian, Ji; Jin, Kaina; Yao, Yuncong

    2014-01-01

    Anthocyanin is a critical factor involved in coloration of plant tissues, but the mechanism how medium pH values affect anthocyanin accumulation in woody plants is unknown. We analyzed anthocyanin composition and the expression of elements encoding anthocyanin and flavonols biosynthesis underlying different medium pH values by using three different leave color type cultivars. HPLC analysis demonstrated that high medium pH values treatment induced a dramatic decrease in the concentration of cyaniding in crabapple leaves. Conversely, the high medium pH values induced up-regulation of the content of flavones and flavonols, suggesting that low pH treatment-induced anthocyanin accumulation. Quantitative real time PCR experiment showed the expression level of anthocyanidin synthase (McANS) and uridine diphosphate glucose flavonoid 3-O-glucosyltransferase (McUFGT) was up-regulated by low pH values treatment, and high medium pH value treatment up-regulate the transcription level of flavonol synthase (McFLS). Meanwhile, several MYB TFs have been suggested in the regulation of pH responses. These results strongly indicate that the low pH treatment-induced anthocyanin accumulation is mediated by the variation of mRNA transcription of the anthocyanin biosynthetic genes. PMID:24914811

  12. Two glycosyltransferases involved in anthocyanin modification delineated by transcriptome independent component analysis in Arabidopsis thaliana

    PubMed Central

    Yonekura-Sakakibara, Keiko; Fukushima, Atsushi; Nakabayashi, Ryo; Hanada, Kousuke; Matsuda, Fumio; Sugawara, Satoko; Inoue, Eri; Kuromori, Takashi; Ito, Takuya; Shinozaki, Kazuo; Wangwattana, Bunyapa; Yamazaki, Mami; Saito, Kazuki

    2012-01-01

    To identify candidate genes involved in Arabidopsis flavonoid biosynthesis, we applied transcriptome coexpression analysis and independent component analyses with 1388 microarray data from publicly available databases. Two glycosyltransferases, UGT79B1 and UGT84A2 were found to cluster with anthocyanin biosynthetic genes. Anthocyanin was drastically reduced in ugt79b1 knockout mutants. Recombinant UGT79B1 protein converted cyanidin 3-O-glucoside to cyanidin 3-O-xylosyl(1→2)glucoside. UGT79B1 recognized 3-O-glucosylated anthocyanidins/flavonols and uridine diphosphate (UDP)-xylose, but not 3,5-O-diglucosylated anthocyanidins, indicating that UGT79B1 encodes anthocyanin 3-O-glucoside: 2′′-O-xylosyltransferase. UGT84A2 is known to encode sinapic acid: UDP-glucosyltransferase. In ugt84a2 knockout mutants, a major sinapoylated anthocyanin was drastically reduced. A comparison of anthocyanin profiles in ugt84a knockout mutants indicated that UGT84A2 plays a major role in sinapoylation of anthocyanin, and that other UGT84As contribute the production of 1-O-sinapoylglucose to a lesser extent. These data suggest major routes from cyanidin 3-O-glucoside to the most highly modified cyanidin in the potential intricate anthocyanin modification pathways in Arabidopsis. PMID:21899608

  13. Anthocyanin Absorption and Metabolism by Human Intestinal Caco-2 Cells--A Review.

    PubMed

    Kamiloglu, Senem; Capanoglu, Esra; Grootaert, Charlotte; Van Camp, John

    2015-09-08

    Anthocyanins from different plant sources have been shown to possess health beneficial effects against a number of chronic diseases. To obtain any influence in a specific tissue or organ, these bioactive compounds must be bioavailable, i.e., effectively absorbed from the gut into the circulation and transferred to the appropriate location within the body while still maintaining their bioactivity. One of the key factors affecting the bioavailability of anthocyanins is their transport through the gut epithelium. The Caco-2 cell line, a human intestinal epithelial cell model derived from a colon carcinoma, has been proven to be a good alternative to animal studies for predicting intestinal absorption of anthocyanins. Studies investigating anthocyanin absorption by Caco-2 cells report very low absorption of these compounds. However, the bioavailability of anthocyanins may be underestimated since the metabolites formed in the course of digestion could be responsible for the health benefits associated with anthocyanins. In this review, we critically discuss recent findings reported on the anthocyanin absorption and metabolism by human intestinal Caco-2 cells.

  14. Resorption Protection. Anthocyanins Facilitate Nutrient Recovery in Autumn by Shielding Leaves from Potentially Damaging Light Levels

    PubMed Central

    Hoch, William A.; Singsaas, Eric L.; McCown, Brent H.

    2003-01-01

    The resorption protection hypothesis, which states that anthocyanins protect foliar nutrient resorption during senescence by shielding photosynthetic tissues from excess light, was tested using wild-type (WT) and anthocyanin-deficient mutants of three deciduous woody species, Cornus sericea, Vaccinium elliottii (Chapmn.), and Viburnum sargentii (Koehne). WT Betula papyrifera (Marsh) was included to compare the senescence performance of a species that does not produce anthocyanins in autumn. Plants were subjected to three environmental regimes during senescence: an outdoor treatment; a 5-d high-stress (high light and low temperature) treatment followed by transfer to a low-stress environment and a low-stress treatment that served as control. In the outdoor treatment, the appearance of anthocyanins in senescing leaves of WT plants was concomitant with the development of photo-inhibition in mutant plants of all three anthocyanin-producing species. In the high-stress environment, WT plants maintained higher photochemical efficiencies than mutants and were able to recover when transferred to the low-stress environment, whereas mutant leaves dropped while still green and displayed signs of irreversible photooxidative damage. Nitrogen resorption efficiencies and proficiencies of all mutants in both stressful treatments were significantly lower than the WT counterparts. B. papyrifera displayed photochemical efficiencies and nitrogen resorption performance comparable with the highest of the anthocyanin-producing species in all three senescing environments, indicating a photoprotective strategy divergent from the other species studied. These results strongly support the resorption protection hypothesis of anthocyanins in senescing leaves. PMID:14526111

  15. Mesophyll-localized phytochromes gate stress- and light-inducible anthocyanin accumulation in Arabidopsis thaliana

    PubMed Central

    Oh, Sookyung; Warnasooriya, Sankalpi N; Montgomery, Beronda L

    2014-01-01

    Abiotic stress and light induce anthocyanin accumulation in Arabidopsis. Here, we demonstrate that mesophyll-localized phytochromes regulate nitrogen-, phosphate- and cold-induced anthocyanin accumulation in shoots of Arabidopsis. Whereas ecotype-dependent differences result in distinct total levels of anthocyanin accumulation in response to light, cold, or nutrient-deficient treatments, phytochromes generally gate light- and/or stress-induced anthocyanin accumulation in shoots, as plants depleted of mesophyll-localized phytochromes lack or have highly attenuated induction of anthocyanins. Observed interactions between light and stress were found to be wavelength dependent, with red and far-red light stimulating higher total levels of anthocyanin accumulation under cold temperatures, especially in response to nitrogen limitation, whereas blue light did not. The roots of plants depleted of mesophyll-localized phytochromes still respond to nutrient deficiency as determined by elongation of primary roots and root hair elongation when plants are grown under nitrogen- or phosphate-limited conditions. Plants which are constitutively deficient in photoreceptors in both shoots and roots, i.e., phy or cry mutants, exhibit defects in light- and stress-induced anthocyanin accumulation and defects in root development. Taken together, these results suggest that the response to nutrient limitation in roots and shoots is under distinct control by spatial-specific pools of phytochromes in Arabidopsis. PMID:24535251

  16. Changes of anthocyanins, anthocyanidins, and antioxidant activity in bilberry extract during dry heating.

    PubMed

    Yue, X; Xu, Z

    2008-08-01

    Thermal stability of 10 anthocyanins found in a bilberry extract was studied at different heating temperatures and times. Degradation of the 10 anthocyanins, delphinidin, cyanidin, petunidin, peonidin, and malvidin derivat with different conjugated sugars, followed 1st-order reaction kinetics at heating temperatures 80, 100, and 125 degrees C. Though the degradation rate constants of anthocyanins were not significantly different from each other at the same heating temperature, they increased drastically when heating temperature was increased to 125 degrees C. At that temperature, the half-lives for all anthocyanins were less than 8 min. The degradation rate constants followed the Arrhenius equation. The trend of lower activation energy of the anthocyanins with arabinoside than with galactoside or glucoside was observed. These conjugated sugars were cleaved from the anthocyanins to produce their corresponding anthocyanidins or aglycones during heating. The production of anthocyanidins increased con stantly and was converted from approximately 30% of the degraded anthocyanins when heated at 100 degrees C for up to 30 min. At 125 degrees C, the increase of anthocyanidins lasted for 10 min, after which the degradation rate of anthocyanidins exceeded the production rate. Antioxidant activities of the heated extracts were estimated by measuring DPPH (2, 2'-diphenyl-1-picrylhydrazyl) free radical scavenging activity. The extracts heated at 80 degrees C for 30 min, 100 degrees C for 10 and 20 min, and 125 degrees C for 10 min had higher free radical scavenging capability than unheated extract.

  17. Cloning and characterization of a potato StAN11 gene involved in anthocyanin biosynthesis regulation.

    PubMed

    Li, Wang; Wang, Bing; Wang, Man; Chen, Min; Yin, Jing-Ming; Kaleri, Ghullam Murtaza; Zhang, Rui-Jie; Zuo, Tie-Niu; You, Xiong; Yang, Qing

    2014-04-01

    Anthocyanins are a class of products of plant secondary metabolism and are responsible for tubers color in potato. The biosynthesis of anthocyanins is a complex biological process, in which multiple genes are involved including structural genes and regulatory genes. In this study, StAN11, a WD40-repeat gene, was cloned from potato cultivar Chieftain (Solanum tuberosum L.). StAN11 (HQ599506) contained no intron and its open reading frame (ORF) was 1,029 bp long, encoding a putative protein of 342 amino acids. In order to verify its role in anthocyanin biosynthesis, StAN11 was inserted behind the CaMV-35S promoter of pCMBIA1304 and the recombination vector was introduced into the potato cultivar Désirée plants by Agrobacterium-mediated transformation. The color of transgenic tuber skin was significantly deepened, compared to the wild-type control, which was highly consistent with the accumulation of anthocyanin and expression of StAN11 in transgenic lines tuber skin. Further analysis on the expression of Flavonone-3-hydroxylase (F3H), Dihydroflavonol reductase (DFR), Anthocyanidin synthase (ANS), and Flavonoid 3-O-glucosyl transferase (3GT) in transgenic plants revealed that only DFR was upregulated. This result suggested that StAN11 regulated anthocyanin biosynthesis in potato by controlling DFR expression and accumulation of anthocyanin could be increased through overexpression of StAN11 in the tubers with the genetic background of anthocyanin biosynthesis. PMID:24304603

  18. Solvent optimization for anthocyanin extraction from Syzygium cumini L. Skeels using response surface methodology.

    PubMed

    Chaudhary, Bratati; Mukhopadhyay, Kunal

    2013-05-01

    Anthocyanins are plant pigments that are potential candidates for use as natural food colourant. In this study, Syzygium cumini fruit skin has been used as anthocyanin source. All the six major types of anthocyanins were identified in the sample by ultra performance liquid chromatography studies, and the antioxidant activity was found to be 4.34 ± 0.26 Fe(2+)g(- 1) in the sample with highest anthocyanin content. Optimization of conditions for extracting high amounts of anthocyanin from the fruit peels was investigated by response surface methodology. The results suggested that highest anthocyanin yield (763.80 mg; 100 ml(- 1)), highest chroma and hue angle in the red colour range could be obtained when 20% ethanol was used in combination with 1% acetic acid. Methanol was replaced with ethanol for the extraction of pigments due to its less toxicity and being safe for human consumption. The optimized solvent can be used to extract anthocyanins from the S. cumini fruits and used as natural colourants in the food industries. PMID:23121325

  19. p53-dependent gene repression through p21 is mediated by recruitment of E2F4 repression complexes.

    PubMed

    Benson, E K; Mungamuri, S K; Attie, O; Kracikova, M; Sachidanandam, R; Manfredi, J J; Aaronson, S A

    2014-07-24

    The p53 tumor suppressor protein is a major sensor of cellular stresses, and upon stabilization, activates or represses many genes that control cell fate decisions. While the mechanism of p53-mediated transactivation is well established, several mechanisms have been proposed for p53-mediated repression. Here, we demonstrate that the cyclin-dependent kinase inhibitor p21 is both necessary and sufficient for the downregulation of known p53-repression targets, including survivin, CDC25C, and CDC25B in response to p53 induction. These same targets are similarly repressed in response to p16 overexpression, implicating the involvement of the shared downstream retinoblastoma (RB)-E2F pathway. We further show that in response to either p53 or p21 induction, E2F4 complexes are specifically recruited onto the promoters of these p53-repression targets. Moreover, abrogation of E2F4 recruitment via the inactivation of RB pocket proteins, but not by RB loss of function alone, prevents the repression of these genes. Finally, our results indicate that E2F4 promoter occupancy is globally associated with p53-repression targets, but not with p53 activation targets, implicating E2F4 complexes as effectors of p21-dependent p53-mediated repression.

  20. Achievements and perspectives in biochemistry concerning anthocyanin modification for blue flower coloration.

    PubMed

    Sasaki, Nobuhiro; Nakayama, Toru

    2015-01-01

    Genetic engineering of roses and other plants of floricultural importance to give them a truly blue petal color is arguably one of the holy grails of plant biotechnology. Toward this goal, bluish carnations and roses were previously engineered by establishing an exclusive accumulation of delphinidin (Dp)-type anthocyanins in their petals via the heterologous expression of a flavonoid 3',5'-hydroxylase gene. Very recently, purple-blue varieties of chrysanthemums were also genetically engineered via a similar biochemical strategy. Although the floral colors of these transgenic plants still lack a true blue color, the basis for the future molecular breeding of truly blue flowers is via the engineering of anthocyanin pathways. Anthocyanins with multiple aromatic acyl groups (often referred to as polyacylated anthocyanins) in the 3'- or 7-position tend to display a more stable blue color than non-acylated anthocyanins. The 7-polyacylation process during the biosynthesis of purple-blue anthocyanins in delphinium (Delphinium grandiflorum) was found to occur in vacuoles using acyl-glucose as both the glucosyl and acyl donor. Glucosyltransferases and acyltransferases involved in anthocyanin 7-polyacylation in delphinium are vacuolar acyl-glucose-dependent enzymes belonging to the glycoside hydrolase family 1 and serine carboxypeptidae-like protein family, respectively. The 7-polyacylation proceeds through the alternate glucosylation and p-hydroxybenzoylation catalyzed by these enzymes. p-Hydroxybenzoyl-glucose serves as the p-hydroxybenzoyl and glucosyl donor to produce anthocyanins modified with a p-hydroxybenzoyl-glucose concatemer at the 7-position. This novel finding has provided a potential breakthrough for the genetic engineering of truly blue flowers, where polyacylated Dp-type anthocyanins are accumulated exclusively in the petals.

  1. An O-methyltransferase modifies accumulation of methylated anthocyanins in seedlings of tomato.

    PubMed

    Gomez Roldan, Maria Victoria; Outchkourov, Nikolay; van Houwelingen, Adèle; Lammers, Michiel; Romero de la Fuente, Irene; Ziklo, Noa; Aharoni, Asaph; Hall, Robert D; Beekwilder, Jules

    2014-11-01

    Anthocyanins contribute to the appearance of fruit by conferring to them a red, blue or purple colour. In a food context, they have also been suggested to promote consumer health. In purple tomato tissues, such as hypocotyls, stems and purple fruits, various anthocyanins accumulate. These molecules have characteristic patterns of modification, including hydroxylations, methylations, glycosylations and acylations. The genetic basis for many of these modifications has not been fully elucidated, and nor has their role in the functioning of anthocyanins. In this paper, AnthOMT, an O-methyltransferase (OMT) mediating the methylation of anthocyanins, has been identified and functionally characterized using a combined metabolomics and transcriptomics approach. Gene candidates were selected from the draft tomato genome, and their expression was subsequently monitored in a tomato seedling system comprising three tissues and involving several time points. In addition, we also followed gene expression in wild-type red and purple transgenic tomato fruits expressing Rosea1 and Delila transcription factors. Of the 57 candidates identified, only a single OMT gene showed patterns strongly correlating with both accumulation of anthocyanins and expression of anthocyanin biosynthesis genes. This candidate (AnthOMT) was compared to a closely related caffeoyl CoA OMT by recombinant expression in Escherichia coli, and then tested for substrate specificity. AnthOMT showed a strong affinity for glycosylated anthocyanins, while other flavonoid glycosides and aglycones were much less preferred. Gene silencing experiments with AnthOMT resulted in reduced levels of the predominant methylated anthocyanins. This confirms the role of this enzyme in the diversification of tomato anthocyanins.

  2. Hypoglycemic activity of a novel Anthocyanin-rich formulation from Lowbush Blueberry, Vaccinium angustifolium Aiton

    PubMed Central

    Grace, Mary H.; Ribnicky, David M.; Kuhn, Peter; Poulev, Alexander; Logendra, Sithes; Yousef, Gad G.; Raskin, Ilya; Lila, Mary Ann

    2009-01-01

    Blueberry fruits are known as a rich source of anthocyanin components. In this study we demonstrate that anthocyanins from blueberry have the potency to alleviate symptoms of hyperglycemia in diabetic C57b1/6J mice. The anti-diabetic activity of different anthocyanin-related extracts was evaluated using the pharmaceutically acceptable self-microemulsifying drug delivery system; Labrasol. Treatment by gavage (500 mg/kg body wt) with a phenolic-rich extract and an anthocyanin-enriched fraction formulated with Labrasol lowered elevated blood glucose levels by 33 and 51%, respectively. The hypoglycemic activities of these formulae were comparable to that of the known anti-diabetic drug metformin (Baily and Day, 2004; 27% at 300 mg/kg). The extracts were not significantly hypoglycemic when administered without Labrasol, demonstrating its bio-enhancing effect, most likely due to increasing the bioavailability of the administered preparations. The phenolic-rich extract contained 287.0 ± 9.7 mg/g anthocyanins, while the anthocyanin-enriched fraction contained 595 ± 20.0 mg/g (cyanidin-3-glucoside equivalents), as measured by HPLC and pH differential analysis methods. The greater hypoglycemic activity of the anthocyanin-enriched fraction compared to the initial phenolic-rich extract suggested that the activity was due to the anthocyanin components. Treatment by gavage (300 mg/kg) with the pure anthocyanins, delphinidin-3-O-glucoside and malvidin-3-O- glucoside, formulated with Labrasol, showed that malvidin-3-O- glucoside was significantly hypoglycemic while delphinidin-3-O-glucoside was not. PMID:19303751

  3. An O-methyltransferase modifies accumulation of methylated anthocyanins in seedlings of tomato.

    PubMed

    Gomez Roldan, Maria Victoria; Outchkourov, Nikolay; van Houwelingen, Adèle; Lammers, Michiel; Romero de la Fuente, Irene; Ziklo, Noa; Aharoni, Asaph; Hall, Robert D; Beekwilder, Jules

    2014-11-01

    Anthocyanins contribute to the appearance of fruit by conferring to them a red, blue or purple colour. In a food context, they have also been suggested to promote consumer health. In purple tomato tissues, such as hypocotyls, stems and purple fruits, various anthocyanins accumulate. These molecules have characteristic patterns of modification, including hydroxylations, methylations, glycosylations and acylations. The genetic basis for many of these modifications has not been fully elucidated, and nor has their role in the functioning of anthocyanins. In this paper, AnthOMT, an O-methyltransferase (OMT) mediating the methylation of anthocyanins, has been identified and functionally characterized using a combined metabolomics and transcriptomics approach. Gene candidates were selected from the draft tomato genome, and their expression was subsequently monitored in a tomato seedling system comprising three tissues and involving several time points. In addition, we also followed gene expression in wild-type red and purple transgenic tomato fruits expressing Rosea1 and Delila transcription factors. Of the 57 candidates identified, only a single OMT gene showed patterns strongly correlating with both accumulation of anthocyanins and expression of anthocyanin biosynthesis genes. This candidate (AnthOMT) was compared to a closely related caffeoyl CoA OMT by recombinant expression in Escherichia coli, and then tested for substrate specificity. AnthOMT showed a strong affinity for glycosylated anthocyanins, while other flavonoid glycosides and aglycones were much less preferred. Gene silencing experiments with AnthOMT resulted in reduced levels of the predominant methylated anthocyanins. This confirms the role of this enzyme in the diversification of tomato anthocyanins. PMID:25227758

  4. Regulation of anthocyanin biosynthesis in Arabidopsis thaliana red pap1-D cells metabolically programmed by auxins.

    PubMed

    Liu, Zhong; Shi, Ming-Zhu; Xie, De-Yu

    2014-04-01

    Red pap1-D cells of Arabidopsis thaliana have been cloned from production of anthocyanin pigmentation 1-Dominant (pap1-D) plants. The red cells are metabolically programmed to produce high levels of anthocyanins by a WD40-bHLH-MYB complex that is composed of the TTG1, TT8/GL3 and PAP1 transcription factors. Here, we report that indole 3-acetic acid (IAA), naphthaleneacetic acid (NAA) and 2,4-dichlorophenoxyacetic acid (2,4-D) regulate anthocyanin biosynthesis in these red cells. Seven concentrations (0, 0.2, 0.4, 2.2, 9, 18 and 27 μM) were tested for the three auxins. IAA and 2,4-D at 2.2-27 μM reduced anthocyanin levels. NAA at 0-0.2 μM or above 9 μM also decreased anthocyanin levels, but from 0.4 to 9 μM, it increased them. HPLC-ESI-MS analysis identified seven cyanin molecules that were produced in red pap1-D cells, and their levels were affected by auxins. The expression levels of ten genes, including six transcription factors (TTG1, EGL3, MYBL2, TT8, GL3 and PAP1) and four pathway genes (PAL1, CHS, DFR and ANS) involved in anthocyanin biosynthesis were analyzed upon various auxin treatments. The resulting data showed that 2,4-D, NAA and IAA control anthocyanin biosynthesis by regulating the expression of TT8, GL3 and PAP1 as well as genes in the anthocyanin biosynthetic pathway, such as DFR and ANS. In addition, the expression of MYBL2, PAL1 and CHS in red pap1-D and wild-type cells differentially respond to the three auxins. Our data demonstrate that the three auxins regulate anthocyanin biosynthesis in metabolically programmed red cells via altering the expression of transcription factor genes and pathway genes. PMID:24370633

  5. High concentrations of aromatic acylated anthocyanins found in cauline hairs in Plectranthus ciliatus.

    PubMed

    Jordheim, Monica; Calcott, Kate; Gould, Kevin S; Davies, Kevin M; Schwinn, Kathy E; Andersen, Øyvind M

    2016-08-01

    Vegetative shoots of a naturalized population of purple-leaved plectranthus (Plectranthus ciliatus, Lamiaceae) were found to contain four main anthocyanins: peonidin 3-(6″-caffeoyl-β-glucopyranoside)-5-β-glucopyranoside, peonidin 3-(6″-caffeoyl-β-glucopyranoside)-5-(6‴-malonyl-β-glucopyranoside), peonidin 3-(6″-E-p-coumaroyl-β-glucopyranoside)-5-(6‴-malonyl-β-glucopyranoside), and peonidin 3-(6″-E-p-coumaroyl-β-glucopyranoside)-5-β-glucopyranoside. The first three of these pigments have not been reported previously from any plant. They all follow the typical anthocyanin pattern of Lamiaceae, with universal occurrence of anthocyanidin 3,5-diglucosides and aromatic acylation with p-coumaric and sometimes caffeic acids; however, they differ by being based on peonidin. The four anthocyanins were present in the leaves (22.2 mg g(-1) DW), and in the xylem and interfascicular parenchyma of the stem. They were exceptionally abundant, among the highest reported for any plant organ, in epidermal hairs on some of the stem internodes (101 mg g(-1) DW). Anthocyanin content in these hairs increased more than three-fold from the youngest to the fourth-youngest internodes. In situ absorbances (λmax ≈ 545 nm) were bathochromic in comparison to absorbances of the isolated anthocyanins in their flavylium form in acidified aqueous solutions (λmax = 525 nm), suggesting that the anthocyanins occur both in quinoidal and flavylium forms in constant proportions in the anthocyanic hair cells. The most distinctive observation with respect to relative proportions of individual anthocyanins was found in de-haired internodes, for which anthocyanin caffeoyl-derivatives decreased, and anthocyanin coumaroyl-derivatives increased, from the youngest to the fourth-youngest internode. PMID:27165277

  6. Unraveling the Mechanism Underlying the Glycosylation and Methylation of Anthocyanins in Peach1[C][W

    PubMed Central

    Cheng, Jun; Wei, Guochao; Zhou, Hui; Gu, Chao; Vimolmangkang, Sornkanok; Liao, Liao; Han, Yuepeng

    2014-01-01

    Modification of anthocyanin plays an important role in increasing its stability in plants. Here, six anthocyanins were identified in peach (Prunus persica), and their structural diversity is attributed to glycosylation and methylation. Interestingly, peach is quite similar to the wild species Prunus ferganensis but differs from both Prunus davidiana and Prunus kansueasis in terms of anthocyanin composition in flowers. This indicates that peach is probably domesticated from P. ferganensis. Subsequently, genes responsible for both methylation and glycosylation of anthocyanins were identified, and their spatiotemporal expression results in different patterns of anthocyanin accumulation in flowers, leaves, and fruits. Two tandem-duplicated genes encoding flavonoid 3-O-glycosyltransferase (F3GT) in peach, PpUGT78A1 and PpUGT78A2, showed different activity toward anthocyanin, providing an example of divergent evolution of F3GT genes in plants. Two genes encoding anthocyanin O-methyltransferase (AOMT), PpAOMT1 and PpAOMT2, are expressed in leaves and flowers, but only PpAOMT2 is responsible for the O-methylation of anthocyanins at the 3′ position in peach. In addition, our study reveals a novel branch of UGT78 genes in plants that lack the highly conserved intron 2 of the UGT gene family, with a great variation of the amino acid residue at position 22 of the plant secondary product glycosyltransferase box. Our results not only provide insights into the mechanisms underlying anthocyanin glycosylation and methylation in peach but will also aid in future attempts to manipulate flavonoid biosynthesis in peach as well as in other plants. PMID:25106821

  7. YjjQ Represses Transcription of flhDC and Additional Loci in Escherichia coli

    PubMed Central

    Wiebe, Helene; Gürlebeck, Doreen; Groß, Jana; Dreck, Katrin; Pannen, Derk; Ewers, Christa; Wieler, Lothar H.

    2015-01-01

    ABSTRACT The presumptive transcriptional regulator YjjQ has been identified as being virulence associated in avian pathogenic Escherichia coli (APEC). In this work, we characterize YjjQ as transcriptional repressor of the flhDC operon, encoding the master regulator of flagellar synthesis, and of additional loci. The latter include gfc (capsule 4 synthesis), ompC (outer membrane porin C), yfiRNB (regulated c-di-GMP synthesis), and loci of poorly defined function (ybhL and ymiA-yciX). We identify the YjjQ DNA-binding sites at the flhDC and gfc promoters and characterize a DNA-binding sequence motif present at all promoters found to be repressed by YjjQ. At the flhDC promoter, the YjjQ DNA-binding site overlaps the RcsA-RcsB DNA-binding site. RcsA-RcsB likewise represses the flhDC promoter, but the repression by YjjQ and that by RcsA-RcsB are independent of each other. These data suggest that YjjQ is an additional regulator involved in the complex control of flhDC at the level of transcription initiation. Furthermore, we show that YjjQ represses motility of the E. coli K-12 laboratory strain and of uropathogenic E. coli (UPEC) strains CFT073 and 536. Regulation of flhDC, yfiRNB, and additional loci by YjjQ may be features relevant for pathogenicity. IMPORTANCE Escherichia coli is a commensal and pathogenic bacterium causing intra- and extraintestinal infections in humans and farm animals. The pathogenicity of E. coli strains is determined by their particular genome content, which includes essential and associated virulence factors that control the cellular physiology in the host environment. However, the gene pools of commensal and pathogenic E. coli are not clearly differentiated, and the function of virulence-associated loci needs to be characterized. In this study, we characterize the function of yjjQ, encoding a transcription regulator that was identified as being virulence associated in avian pathogenic E. coli (APEC). We characterize YjjQ as transcriptional

  8. Translational Repression of NhaR, a Novel Pathway for Multi-Tier Regulation of Biofilm Circuitry by CsrA

    PubMed Central

    Pannuri, Archana; Yakhnin, Helen; Vakulskas, Christopher A.; Edwards, Adrianne N.; Babitzke, Paul

    2012-01-01

    The RNA binding protein CsrA (RsmA) represses biofilm formation in several proteobacterial species. In Escherichia coli, it represses the production of the polysaccharide adhesin poly-β-1,6-N-acetyl-d-glucosamine (PGA) by binding to the pgaABCD mRNA leader, inhibiting pgaA translation, and destabilizing this transcript. In addition, CsrA represses genes responsible for the synthesis of cyclic di-GMP, an activator of PGA production. Here we determined that CsrA also represses NhaR, a LysR-type transcriptional regulator which responds to elevated [Na+] and alkaline pH and activates the transcription of the pgaABCD operon. Gel shift studies revealed that CsrA binds at two sites in the 5′ untranslated segment of nhaR, one of which overlaps the Shine-Dalgarno sequence. An epitope-tagged NhaR protein, expressed from the nhaR chromosomal locus, and an nhaR posttranscriptional reporter fusion (PlacUV5-nhaR′-′lacZ) both showed robust repression by CsrA. Northern blotting revealed a complex transcription pattern for the nhaAR locus. Nevertheless, CsrA did not repress nhaR mRNA levels. Toeprinting assays showed that CsrA competes effectively with the ribosome for binding to the translation initiation region of nhaR. Together, these findings indicate that CsrA blocks nhaR translation. Epistasis studies with a pgaA-lacZ transcriptional fusion confirmed a model in which CsrA indirectly represses pgaABCD transcription via NhaR. We conclude that CsrA regulates the horizontally acquired pgaABCD operon and PGA biosynthesis at multiple levels. Furthermore, nhaR repression exemplifies an expanding role for CsrA as a global regulator of stress response systems. PMID:22037401

  9. Two LcbHLH Transcription Factors Interacting with LcMYB1 in Regulating Late Structural Genes of Anthocyanin Biosynthesis in Nicotiana and Litchi chinensis During Anthocyanin Accumulation

    PubMed Central

    Lai, Biao; Du, Li-Na; Liu, Rui; Hu, Bing; Su, Wen-Bing; Qin, Yong-Hua; Zhao, Jie-Tang; Wang, Hui-Cong; Hu, Gui-Bing

    2016-01-01

    Anthocyanin biosynthesis requires the MYB-bHLH-WD40 protein complex to activate the late biosynthetic genes. LcMYB1 was thought to act as key regulator in anthocyanin biosynthesis of litchi. However, basic helix-loop-helix proteins (bHLHs) as partners have not been identified yet. The present study describes the functional characterization of three litchi bHLH candidate anthocyanin regulators, LcbHLH1, LcbHLH2, and LcbHLH3. Although these three litchi bHLHs phylogenetically clustered with bHLH proteins involved in anthcoyanin biosynthesis in other plant, only LcbHLH1 and LcbHLH3 were found to localize in the nucleus and physically interact with LcMYB1. The transcription levels of all these bHLHs were not coordinated with anthocyanin accumulation in different tissues and during development. However, when co-infiltrated with LcMYB1, both LcbHLH1 and LcbHLH3 enhanced anthocyanin accumulation in tobacco leaves with LcbHLH3 being the best inducer. Significant accumulation of anthocyanins in leaves transformed with the combination of LcMYB1 and LcbHLH3 were noticed, and this was associated with the up-regulation of two tobacco endogenous bHLH regulators, NtAn1a and NtAn1b, and late structural genes, like NtDFR and NtANS. Significant activity of the ANS promoter was observed in transient expression assays either with LcMYB1-LcbHLH1 or LcMYB1-LcbHLH3, while only minute activity was detected after transformation with only LcMYB1. In contrast, no activity was measured after induction with the combination of LcbHLH2 and LcMYB1. Higher DFR expression was also oberseved in paralleling with higher anthocyanins in co-transformed lines. LcbHLH1 and LcbHLH3 are essential partner of LcMYB1 in regulating the anthocyanin production in tobacco and probably also in litchi. The LcMYB1-LcbHLH complex enhanced anthocyanin accumulation may associate with activating the transcription of DFR and ANS. PMID:26925082

  10. Two LcbHLH Transcription Factors Interacting with LcMYB1 in Regulating Late Structural Genes of Anthocyanin Biosynthesis in Nicotiana and Litchi chinensis During Anthocyanin Accumulation.

    PubMed

    Lai, Biao; Du, Li-Na; Liu, Rui; Hu, Bing; Su, Wen-Bing; Qin, Yong-Hua; Zhao, Jie-Tang; Wang, Hui-Cong; Hu, Gui-Bing

    2016-01-01

    Anthocyanin biosynthesis requires the MYB-bHLH-WD40 protein complex to activate the late biosynthetic genes. LcMYB1 was thought to act as key regulator in anthocyanin biosynthesis of litchi. However, basic helix-loop-helix proteins (bHLHs) as partners have not been identified yet. The present study describes the functional characterization of three litchi bHLH candidate anthocyanin regulators, LcbHLH1, LcbHLH2, and LcbHLH3. Although these three litchi bHLHs phylogenetically clustered with bHLH proteins involved in anthcoyanin biosynthesis in other plant, only LcbHLH1 and LcbHLH3 were found to localize in the nucleus and physically interact with LcMYB1. The transcription levels of all these bHLHs were not coordinated with anthocyanin accumulation in different tissues and during development. However, when co-infiltrated with LcMYB1, both LcbHLH1 and LcbHLH3 enhanced anthocyanin accumulation in tobacco leaves with LcbHLH3 being the best inducer. Significant accumulation of anthocyanins in leaves transformed with the combination of LcMYB1 and LcbHLH3 were noticed, and this was associated with the up-regulation of two tobacco endogenous bHLH regulators, NtAn1a and NtAn1b, and late structural genes, like NtDFR and NtANS. Significant activity of the ANS promoter was observed in transient expression assays either with LcMYB1-LcbHLH1 or LcMYB1-LcbHLH3, while only minute activity was detected after transformation with only LcMYB1. In contrast, no activity was measured after induction with the combination of LcbHLH2 and LcMYB1. Higher DFR expression was also oberseved in paralleling with higher anthocyanins in co-transformed lines. LcbHLH1 and LcbHLH3 are essential partner of LcMYB1 in regulating the anthocyanin production in tobacco and probably also in litchi. The LcMYB1-LcbHLH complex enhanced anthocyanin accumulation may associate with activating the transcription of DFR and ANS. PMID:26925082

  11. MafG Sumoylation Is Required for Active Transcriptional Repression

    PubMed Central

    Motohashi, Hozumi; Katsuoka, Fumiki; Miyoshi, Chika; Uchimura, Yasuhiro; Saitoh, Hisato; Francastel, Claire; Engel, James Douglas; Yamamoto, Masayuki

    2006-01-01

    A straightforward mechanism for eliciting transcriptional repression would be to simply block the DNA binding site for activators. Such passive repression is often mediated by transcription factors that lack an intrinsic repressor activity. MafG is a bidirectional regulator of transcription, a repressor in its homodimeric state but an activator when heterodimerized with p45. Here, we report that MafG is conjugated to SUMO-2/3 in vivo. To clarify the possible physiological role(s) for sumoylation in regulating MafG activity, we evaluated mutant and wild-type MafG in transgenic mice and cultured cells. Whereas sumoylation-deficient MafG activated p45-dependent transcription normally and did not affect heterodimer activity, repression by the sumoylation-deficient MafG mutant was severely compromised in vivo. Furthermore, the SUMO-dependent repression activity of MafG was sensitive to histone deacetylase inhibition. Thus, repression by MafG is not achieved through simple passive repression by competing for the activator binding site but requires sumoylation, which then mediates transcriptional repression through recruitment of a repressor complex containing histone deacetylase activity. PMID:16738329

  12. BrMYB4, a suppressor of genes for phenylpropanoid and anthocyanin biosynthesis, is down-regulated by UV-B but not by pigment-inducing sunlight in turnip cv. Tsuda.

    PubMed

    Zhang, Lili; Wang, Yu; Sun, Mei; Wang, Jing; Kawabata, Saneyuki; Li, Yuhua

    2014-12-01

    The regulation of light-dependent anthocyanin biosynthesis in Brassica rapa subsp. rapa cv. Tsuda turnip was investigated using an ethyl methanesulfonate (EMS)-induced mutant R30 with light-independent pigmentation. TILLING (targeting induced local lesions in genomes) and subsequent analysis showed that a stop codon was inserted in the R2R3-MYB transcription factor gene BrMYB4 and that the encoded protein (BrMYB4mu) had lost its C-terminal region. In R30, anthocyanin accumulated in the below-ground portion of the storage root of 2-month-old plants. In 4-day-old seedlings and 2-month-old plants, expression of BrMYB4 was similar between R30 and the wild type (WT), but the expression of the cinnamate 4-hydroxylase gene (BrC4H) was markedly enhanced in R30 in the dark. In turnip seedlings, BrMYB4 expression was suppressed by UV-B irradiation in the WT, but this negative regulation was absent in R30. Concomitantly, BrC4H was repressed by UV-B irradiation in the WT, but stayed at high levels in R30. A gel-shift assay revealed that BrMYB4 could directly bind to the promoter region of BrC4H, but BrMYB4mu could not. The BrMYB4-enhanced green fluorescent protein (eGFP) protein could enter the nucleus in the presence of BrSAD2 (an importin β-like protein) nuclear transporter, but BrMYB4mu-eGFP could not. These results showed that BrMYB4 functions as a negative transcriptional regulator of BrC4H and mediates UV-B-dependent phenylpropanoid biosynthesis, while BrMYB4mu has lost this function. In the storage roots, the expression of anthocyanin biosynthesis genes was enhanced in R30 in the dark and in sunlight in both the WT and R30. However, in the WT, anthocyanin-inducing sunlight did not suppress BrMYB4 expression. Therefore, sunlight-induced anthocyanin biosynthesis does not seem to be regulated by BrMYB4.

  13. BrMYB4, a suppressor of genes for phenylpropanoid and anthocyanin biosynthesis, is down-regulated by UV-B but not by pigment-inducing sunlight in turnip cv. Tsuda.

    PubMed

    Zhang, Lili; Wang, Yu; Sun, Mei; Wang, Jing; Kawabata, Saneyuki; Li, Yuhua

    2014-12-01

    The regulation of light-dependent anthocyanin biosynthesis in Brassica rapa subsp. rapa cv. Tsuda turnip was investigated using an ethyl methanesulfonate (EMS)-induced mutant R30 with light-independent pigmentation. TILLING (targeting induced local lesions in genomes) and subsequent analysis showed that a stop codon was inserted in the R2R3-MYB transcription factor gene BrMYB4 and that the encoded protein (BrMYB4mu) had lost its C-terminal region. In R30, anthocyanin accumulated in the below-ground portion of the storage root of 2-month-old plants. In 4-day-old seedlings and 2-month-old plants, expression of BrMYB4 was similar between R30 and the wild type (WT), but the expression of the cinnamate 4-hydroxylase gene (BrC4H) was markedly enhanced in R30 in the dark. In turnip seedlings, BrMYB4 expression was suppressed by UV-B irradiation in the WT, but this negative regulation was absent in R30. Concomitantly, BrC4H was repressed by UV-B irradiation in the WT, but stayed at high levels in R30. A gel-shift assay revealed that BrMYB4 could directly bind to the promoter region of BrC4H, but BrMYB4mu could not. The BrMYB4-enhanced green fluorescent protein (eGFP) protein could enter the nucleus in the presence of BrSAD2 (an importin β-like protein) nuclear transporter, but BrMYB4mu-eGFP could not. These results showed that BrMYB4 functions as a negative transcriptional regulator of BrC4H and mediates UV-B-dependent phenylpropanoid biosynthesis, while BrMYB4mu has lost this function. In the storage roots, the expression of anthocyanin biosynthesis genes was enhanced in R30 in the dark and in sunlight in both the WT and R30. However, in the WT, anthocyanin-inducing sunlight did not suppress BrMYB4 expression. Therefore, sunlight-induced anthocyanin biosynthesis does not seem to be regulated by BrMYB4. PMID:25305244

  14. Anthocyanins from the scarlet flowers of Anemone coronaria.

    PubMed

    Toki, K; Saito, N; Shigihara, A; Honda, T

    2001-04-01

    Three acylated anthocyanins were isolated from the scarlet flowers of Anemone coronaria 'St. Brigid Red' along with a known pigment, pelargonidin 3-lathyroside. The structures of the acylated pigments were based on a pelargonidin 3-lathyroside skeleton acylated at different positions with malonic acid. The first pigment was identified as pelargonidin 3-O-[2-(beta-D-xylopyranosyl)-6-O-(malonyl)-beta-D-galactopyranoside], the second was pelargonidin 3-O-[2-O-(beta-D-xylopyranosyl)-6-O-(methyl-malonyl)-beta-D-galactopyranoside], and the third was (6''-O-(pelargonidin 3-O-[2''-O-(beta-D-xylopyranosyl)-beta-D-galactopyranosyl]))((4-O-(beta-D-glucopyranosyl)-trans-caffeoyl)-O-tartatryl)malonate.

  15. Repressed mRNAs of muscle cells

    SciTech Connect

    Bag, J.; Pramanik, S.

    1986-05-01

    In rat L-6 muscle cells cytoplasmic mRNAs have been found in two compartments polysome bound and free (or non polysomal). The mRNAs were differentially distributed in these two compartments. The mRNA for a polypeptide of molecular weight 60,000 daltons was present predominantly in the free or non polysomal fraction. We have prepared a cDNA library from the non polysomal mRNAs of L-6 myoblasts. This library was screened by using /sup 32/P labeled cDNA prepared from both polysomal and non polysomal mRNAs. We were able to isolate ten colonies which produced strong signals only when /sup 32/P cDNA from non polysomal mRNAs were used. The DNA from two of these colonies hybridized to two different mRNAs. These two clones were used to quantitate the mRNAs in polysomal and non polysomal fractions. It was found that one clone (D-12) hybridized to a mRNA 60% of which was present in the non polysomal fraction. On the other hand a second clone (P-5) hybridized to a mRNA 80% of which was repressed (non polysomal). Further studies are in progress to examine the mechanism of translational block of these two mRNAs.

  16. [Expression of the genes involved in anthocyanin biosynthesis of 'Tsuda' turnip].

    PubMed

    Xu, Zhi-Ru; Li, Yu-Hua

    2006-10-01

    'Tsuda' turnip (Brassica campestris L. ssp. rapa), in which roots anthocyanin pigmentation is light-sensitive, was used as the material. 'Tsuda' plants were held in darkness or irradiated with sun light and constant light for different time. Anthocyanins in root peel of 'Tsuda' turnip exposed to constant light were identified and quantified with a UV-visual spectrophotometer. The results demonstrated that the anthocyanins accumulation in 'Tsuda' was related with light-exposure time (Fig.1 and Table 1). Fragments of genes selected from the subtraction library of 'Tsuda' turnip involved in anthocyanin biosynthesis were used as probes. The Northern blotting results showed that the expression of PAL, CHS, F3H, DFR and ANS could be induced by irradiation with light and the expression of these genes was related with light exposure time. The expression of MYB was basically the same whether in darkness or in light (Figs.2,3).

  17. An analytical pipeline to compare and characterise the anthocyanin antioxidant activities of purple sweet potato cultivars.

    PubMed

    Hu, Yijie; Deng, Liqing; Chen, Jinwu; Zhou, Siyu; Liu, Shuang; Fu, Yufan; Yang, Chunxian; Liao, Zhihua; Chen, Min

    2016-03-01

    Purple sweet potato (Ipomoea batatas L.) is rich in anthocyanin pigments, which are valuable constituents of the human diet. Techniques to identify and quantify anthocyanins and their antioxidant potential are desirable for cultivar selection and breeding. In this study, we performed a quantitative and qualitative chemical analysis of 30 purple sweet potato (PSP) cultivars, using various assays to measure reducing power radical-scavenging activities, and linoleic acid autoxidation inhibition activity. Grey relational analysis (GRA) was applied to establish relationships between the antioxidant activities and the chemical fingerprints, in order to identify key bioactive compounds. The results indicated that four peonidin-based anthocyanins and three cyanidin-based anthocyanins make significant contributions to antioxidant activity. We conclude that the analytical pipeline described here represents an effective method to evaluate the antioxidant potential of, and the contributing compounds present in, PSP cultivars. This approach may be used to guide future breeding strategies.

  18. Characterization and structures of anthocyanin pigments generated in rosé cider during vinification.

    PubMed

    Shoji, Toshihiko; Goda, Yukihiro; Toyoda, Masatake; Yanagida, Akio; Kanda, Tomomasa

    2002-01-01

    Anthocyanin pigments, which are not found in apple juice, were detected in rosé cider. We confirmed by HPLC/DAD and LC/ESI-MS analyses that some of these anthocyanin pigments generated in rosé cider during vinification corresponded to those formed in model cider containing anthocyanin and flavan-3-ol in the presence of acetaldehyde. To confirm their structures, two anthocyanin pigments formed in a model cider containing cyanidin-3-galactoside and (-)-epicatechin in the presence of acetaldehyde were isolated and purified, and their structures were elucidated by high resolution FAB-MS and (1)H and (13)C NMR analyses. These two pigments were found to consist of cyanidin-3-galactoside and (-)-epicatechin linked by a CH(3)-CH bridge at the 8-position. They were diastereomers that differed in the configuration of the asymmetric methine carbon.

  19. Harvest date affects aronia juice polyphenols, sugars, and antioxidant activity, but not anthocyanin stability.

    PubMed

    Bolling, Bradley W; Taheri, Rod; Pei, Ruisong; Kranz, Sarah; Yu, Mo; Durocher, Shelley N; Brand, Mark H

    2015-11-15

    The goal of this work was to characterize how the date of harvest of 'Viking' aronia berry impacts juice pigmentation, sugars, and antioxidant activity. Aronia juice anthocyanins doubled at the fifth week of the harvest, and then decreased. Juice hydroxycinnamic acids decreased 33% from the first week, while proanthocyanidins increased 64%. Juice fructose and glucose plateaued at the fourth week, but sorbitol increased 40% to the seventh harvest week. Aronia juice pigment density increased due to anthocyanin concentration, and polyphenol copigmentation did not significantly affect juice pigmentation. Anthocyanin stability at pH 4.5 was similar between weeks. However, addition of quercetin, sorbitol, and chlorogenic acid to aronia anthocyanins inhibited pH-induced loss of color. Sorbitol and citric acid may be partially responsible for weekly variation in antioxidant activity, as addition of these agents inhibited DPPH scavenging 13-30%. Thus, aronia polyphenol and non-polyphenol components contribute to its colorant and antioxidant functionality. PMID:25977015

  20. Impact of Frozen Storage on the Anthocyanin and Polyphenol Content of American Elderberry Fruit Juice

    PubMed Central

    Johnson, Mitch C.; Thomas, Andrew L.; Greenlief, C. Michael

    2015-01-01

    The effects of frozen storage on the anthocyanin and polyphenol content of elderberry fruit juice are investigated. Juice from three genotypes of American elderberry (Adams II, Bob Gordon, and Wyldewood) was screened for total phenolic (TP) and total monomeric anthocyanin (TMA) content with spectrophotometric methods. The individual anthocyanin content (IAC) of the juice was tested by coupling solid phase extraction with ultra-performance liquid chromatography/tandem mass spectrometry. Juice samples were tested initially upon harvest, then again after 3, 6, and 9 months of frozen storage. Juice from the three different genotypes had significantly different TP, TMA, and IAC profiles initially (p<0.05). The TP,, TMA, and IAC content of the juice from different genotypes were significantly affected (p<0.05) by the frozen storage time, suggesting that both genotype and length of frozen storage time can affect the anthocyanin content of elderberry fruit juice. PMID:26028422

  1. Harvest date affects aronia juice polyphenols, sugars, and antioxidant activity, but not anthocyanin stability.

    PubMed

    Bolling, Bradley W; Taheri, Rod; Pei, Ruisong; Kranz, Sarah; Yu, Mo; Durocher, Shelley N; Brand, Mark H

    2015-11-15

    The goal of this work was to characterize how the date of harvest of 'Viking' aronia berry impacts juice pigmentation, sugars, and antioxidant activity. Aronia juice anthocyanins doubled at the fifth week of the harvest, and then decreased. Juice hydroxycinnamic acids decreased 33% from the first week, while proanthocyanidins increased 64%. Juice fructose and glucose plateaued at the fourth week, but sorbitol increased 40% to the seventh harvest week. Aronia juice pigment density increased due to anthocyanin concentration, and polyphenol copigmentation did not significantly affect juice pigmentation. Anthocyanin stability at pH 4.5 was similar between weeks. However, addition of quercetin, sorbitol, and chlorogenic acid to aronia anthocyanins inhibited pH-induced loss of color. Sorbitol and citric acid may be partially responsible for weekly variation in antioxidant activity, as addition of these agents inhibited DPPH scavenging 13-30%. Thus, aronia polyphenol and non-polyphenol components contribute to its colorant and antioxidant functionality.

  2. Antioxidant capacities and anthocyanin characteristics of the black-red wild berries obtained in Northeast China.

    PubMed

    Feng, Chengyong; Su, Shang; Wang, Lijin; Wu, Jie; Tang, Zhongqiu; Xu, Yanjun; Shu, Qingyan; Wang, Liangsheng

    2016-08-01

    Various edible berries widely accessible in nature in Northeast China are poorly exploited. The compositions and contents of anthocyanins in black (Padus maackii, Padus avium, Lonicera caerulea, and Ribes nigrum) and red (Ribes rubrum, Sambucus williamsii, Rubus idaeus, and Ribes procumbens) wild berries in Northeast China were firstly characterized by HPLC-DAD/ESI-MS(2). Twenty-three anthocyanins were detected and identified. Cyanidin glycosides were dominant in both berries. Six anthocyanins were reported for the first time in P. avium, R. rubrum, and Sambucus. Total anthocyanin content (TAC) ranged from 10mg/100gfreshweight (FW) (R. procumbens) to 1058mg/100gFW (P. maackii) among berries. The TACs and antioxidant activities assessed by DPPH and FRAP assays were much higher in black than in red berries. Black-red berries, especially P. maackii and P. avium, can be used in developing functional foods and in improving breeding programs. PMID:26988488

  3. Antioxidant capacities and anthocyanin characteristics of the black-red wild berries obtained in Northeast China.

    PubMed

    Feng, Chengyong; Su, Shang; Wang, Lijin; Wu, Jie; Tang, Zhongqiu; Xu, Yanjun; Shu, Qingyan; Wang, Liangsheng

    2016-08-01

    Various edible berries widely accessible in nature in Northeast China are poorly exploited. The compositions and contents of anthocyanins in black (Padus maackii, Padus avium, Lonicera caerulea, and Ribes nigrum) and red (Ribes rubrum, Sambucus williamsii, Rubus idaeus, and Ribes procumbens) wild berries in Northeast China were firstly characterized by HPLC-DAD/ESI-MS(2). Twenty-three anthocyanins were detected and identified. Cyanidin glycosides were dominant in both berries. Six anthocyanins were reported for the first time in P. avium, R. rubrum, and Sambucus. Total anthocyanin content (TAC) ranged from 10mg/100gfreshweight (FW) (R. procumbens) to 1058mg/100gFW (P. maackii) among berries. The TACs and antioxidant activities assessed by DPPH and FRAP assays were much higher in black than in red berries. Black-red berries, especially P. maackii and P. avium, can be used in developing functional foods and in improving breeding programs.

  4. Dietary anthocyanins as a complementary medicinal approach for management of inflammatory bowel disease.

    PubMed

    Sodagari, Hamid Reza; Farzaei, Mohammad Hosein; Bahramsoltani, Roodabeh; Abdolghaffari, Amir Hossein; Mahmoudi, Maryam; Rezaei, Nima

    2015-06-01

    Inflammatory bowel disease (IBD) is thought to result from a chronic or relapsing activation of the immune system in the GI tract. A growing body of evidence confirms the health benefits of dietary anthocyanins as plant-derived natural agents. The aim of this review is to provide an overview of several natural products rich in anthocyanins used worldwide for the treatment of IBD. Anthocyanins possess both protective and therapeutic functions in the management of IBD by alleviating oxidative stress processes, cytoprotective functions, downregulation of inflammatory cytokines and suppressing cellular signaling pathways of inflammatory processes. In conclusion, the consumption of anthocyanin-rich natural formulations must be promoted on the basis of their possible function in the prevention and treatment of gastrointestinal inflammatory disorders.

  5. [Expression of the genes involved in anthocyanin biosynthesis of 'Tsuda' turnip].

    PubMed

    Xu, Zhi-Ru; Li, Yu-Hua

    2006-10-01

    'Tsuda' turnip (Brassica campestris L. ssp. rapa), in which roots anthocyanin pigmentation is light-sensitive, was used as the material. 'Tsuda' plants were held in darkness or irradiated with sun light and constant light for different time. Anthocyanins in root peel of 'Tsuda' turnip exposed to constant light were identified and quantified with a UV-visual spectrophotometer. The results demonstrated that the anthocyanins accumulation in 'Tsuda' was related with light-exposure time (Fig.1 and Table 1). Fragments of genes selected from the subtraction library of 'Tsuda' turnip involved in anthocyanin biosynthesis were used as probes. The Northern blotting results showed that the expression of PAL, CHS, F3H, DFR and ANS could be induced by irradiation with light and the expression of these genes was related with light exposure time. The expression of MYB was basically the same whether in darkness or in light (Figs.2,3). PMID:17075183

  6. Composition and antioxidant activity of the anthocyanins of the fruit of Berberis heteropoda Schrenk.

    PubMed

    Sun, Li-Li; Gao, Wan; Zhang, Meng-Meng; Li, Cheng; Wang, Ai-Guo; Su, Ya-Lun; Ji, Teng-Fei

    2014-11-19

    In present study, the anthocyanin composition and content of the fruit of B. heteropoda Schrenk were determined for the first time. The total anthocyanins were extracted from the fruit of B. heteropoda Schrenk using 0.5% HCl in 80% methanol and were then purified using an AB-8 macroporous resin column. The purified anthocyanin extract (PAE) was evaluated by high-performance liquid chromatography with a diode array detector (HPLC-DAD) and HPLC-high resolution-electrospray ionization-mass spectrometry (HPLC-HR-ESI-MS) under the same experimental conditions. The results revealed the presence of seven different anthocyanins. The major anthocyanins purified by preparative HPLC were confirmed to be delphinidin-3-O-glucopyranoside (30.3%), cyanidin-3-O-glucopyranoside (33.5%), petunidin-3-Ο-glucopyranoside (10.5%), peonidin-3-O-glucopyranoside (8.5%) and malvidin-3-O-glucopyranoside (13.8%) using HPLC-HR-ESI-MS and NMR spectroscopy. The total anthocyanin content was 2036.6 ± 2.2 mg/100 g of the fresh weight of B. heteropoda Schrenk fruit. In terms of its total reducing capacity assay, DPPH radical-scavenging activity assay, ferric-reducing antioxidant power (FRAP) assay and ABTS radical cation-scavenging activity assay, the PAE also showed potent antioxidant activity. The results are valuable for illuminating anthocyanins composition of B. heteropoda Schrenk and for further utilising them as a promising anthocyanin pigment source. This research enriched the chemical information of B. heteropoda Schrenk.

  7. Highly selective separation and purification of anthocyanins from bilberry based on a macroporous polymeric adsorbent.

    PubMed

    Yao, Lijuan; Zhang, Na; Wang, Chenbiao; Wang, Chunhong

    2015-04-01

    Powdered bilberry extract (United States Pharmacopoeia, USP35-NF30), which is prepared from ripe bilberry fruits (Vaccinium myrtillus L.), is the main ingredient of drugs alleviating visual fatigue and diabetic retinopathy because of the rich anthocyanins (purity of 36%). In this study, a method based on a macroporous polymeric adsorbent was established to obtain anthocyanin compounds from bilberry, in which the purity of the anthocyanins was improved to 96%, conducive to further pharmacological research and improvement of the efficiency of the drug. On the basis of the structure of anthocyanins, we designed a series of macroporous polymeric adsorbents based on the copolymerization of divinylbenzene (DVB) and ethylene glycol dimethyl acrylate (EGDMA). In this situation, EGDMA not only regulated the polarity of the adsorbent but also acted as the cross-linking agent to ensure the matrix structure of the adsorbent, which had a high specific surface area and could provide more interaction sites during adsorption with anthocyanins. Among the synthesized polymeric adsorbents with different contents of EGDMA, the one with 20% EGDMA content (DE-20) was demonstrated to exhibit optimal adsorption capacity and selectivity to anthocyanins compared to various commercial adsorbents through static adsorption and desorption experiments. In addition, the optimum condition of the dynamic adsorption-desorption experiment was further explored. The results indicated that the purity of anthocyanins after rinsing with 20% ethanol was determined to be approximately 96% at a desorption ratio of 83%, which was clearly higher than that in powdered bilberry extract. The established separation and purification method of anthocyanins with high purity is expected to be applied in industrial production. PMID:25786117

  8. Functional Characterization of Dihydroflavonol-4-Reductase in Anthocyanin Biosynthesis of Purple Sweet Potato Underlies the Direct Evidence of Anthocyanins Function against Abiotic Stresses

    PubMed Central

    Wang, Hongxia; Fan, Weijuan; Li, Hong; Yang, Jun; Huang, Jirong; Zhang, Peng

    2013-01-01

    Dihydroflavonol-4-reductase (DFR) is a key enzyme in the catalysis of the stereospecific reduction of dihydroflavonols to leucoanthocyanidins in anthocyanin biosynthesis. In the purple sweet potato (Ipomoea batatas Lam.) cv. Ayamurasaki, expression of the IbDFR gene was strongly associated with anthocyanin accumulation in leaves, stems and roots. Overexpression of the IbDFR in Arabidopsis tt3 mutants fully complemented the pigmentation phenotype of the seed coat, cotyledon and hypocotyl. Downregulation of IbDFR expression in transgenic sweet potato (DFRi) using an RNAi approach dramatically reduced anthocyanin accumulation in young leaves, stems and storage roots. In contrast, the increase of flavonols quercetin-3-O-hexose-hexoside and quercetin-3-O-glucoside in the leaves and roots of DFRi plants is significant. Therefore, the metabolic pathway channeled greater flavonol influx in the DFRi plants when their anthocyanin and proanthocyanidin accumulation were decreased. These plants also displayed reduced antioxidant capacity compared to the wild type. After 24 h of cold treatment and 2 h recovery, the wild-type plants were almost fully restored to the initial phenotype compared to the slower recovery of DFRi plants, in which the levels of electrolyte leakage and hydrogen peroxide accumulation were dramatically increased. These results provide direct evidence of anthocyanins function in the protection against oxidative stress in the sweet potato. The molecular characterization of the IbDFR gene in the sweet potato not only confirms its important roles in flavonoid metabolism but also supports the protective function of anthocyanins of enhanced scavenging of reactive oxygen radicals in plants under stressful conditions. PMID:24223813

  9. Functional characterization of Dihydroflavonol-4-reductase in anthocyanin biosynthesis of purple sweet potato underlies the direct evidence of anthocyanins function against abiotic stresses.

    PubMed

    Wang, Hongxia; Fan, Weijuan; Li, Hong; Yang, Jun; Huang, Jirong; Zhang, Peng

    2013-01-01

    Dihydroflavonol-4-reductase (DFR) is a key enzyme in the catalysis of the stereospecific reduction of dihydroflavonols to leucoanthocyanidins in anthocyanin biosynthesis. In the purple sweet potato (Ipomoea batatas Lam.) cv. Ayamurasaki, expression of the IbDFR gene was strongly associated with anthocyanin accumulation in leaves, stems and roots. Overexpression of the IbDFR in Arabidopsis tt3 mutants fully complemented the pigmentation phenotype of the seed coat, cotyledon and hypocotyl. Downregulation of IbDFR expression in transgenic sweet potato (DFRi) using an RNAi approach dramatically reduced anthocyanin accumulation in young leaves, stems and storage roots. In contrast, the increase of flavonols quercetin-3-O-hexose-hexoside and quercetin-3-O-glucoside in the leaves and roots of DFRi plants is significant. Therefore, the metabolic pathway channeled greater flavonol influx in the DFRi plants when their anthocyanin and proanthocyanidin accumulation were decreased. These plants also displayed reduced antioxidant capacity compared to the wild type. After 24 h of cold treatment and 2 h recovery, the wild-type plants were almost fully restored to the initial phenotype compared to the slower recovery of DFRi plants, in which the levels of electrolyte leakage and hydrogen peroxide accumulation were dramatically increased. These results provide direct evidence of anthocyanins function in the protection against oxidative stress in the sweet potato. The molecular characterization of the IbDFR gene in the sweet potato not only confirms its important roles in flavonoid metabolism but also supports the protective function of anthocyanins of enhanced scavenging of reactive oxygen radicals in plants under stressful conditions. PMID:24223813

  10. Protective Effect of Anthocyanins from Lingonberry on Radiation-induced Damages

    PubMed Central

    Fan, Zi-Luan; Wang, Zhen-Yu; Zuo, Li-Li; Tian, Shuang-Qi

    2012-01-01

    There is a growing concern about the serious harm of radioactive materials, which are widely used in energy production, scientific research, medicine, industry and other areas. In recent years, owing to the great side effects of anti-radiation drugs, research on the radiation protectants has gradually expanded from the previous chemicals to the use of natural anti-radiation drugs and functional foods. Some reports have confirmed that anthocyanins are good antioxidants, which can effectively eliminate free radicals, but studies on the immunoregulatory and anti-radiation effects of anthocyanins from lingonberry (ALB) are less reported. In this experiment, mice were given orally once daily for 14 consecutive days before exposure to 6 Gy of gamma-radiation and were sacrificed on the 7th day post-irradiation. The results showed that the selected dose of extract did not lead to acute toxicity in mice; while groups given anthocyanins orally were significantly better than radiation control group according to blood analysis; pretreatment of anthocyanins significantly (p < 0.05) enhanced the thymus and spleen indices and spleen cell survival compared to the irradiation control group. Pretreatment with anthocyanins before irradiation significantly reduced the numbers of micronuclei (MN) in bone marrow polychromatic erythrocytes (PCEs). These findings indicate that anthocyanins have immunostimulatory potential against immunosuppression induced by the radiation. PMID:23249859

  11. Physiological and genetic analysis of Arabidopsis thaliana anthocyanin biosynthesis mutants under chronic adverse environmental conditions.

    PubMed

    Misyura, Maksym; Colasanti, Joseph; Rothstein, Steven J

    2013-01-01

    Anthocyanin production is a characteristic response of flowering plants to unfavourable environmental conditions. The potential roles of flavonoids and anthocyanins in plant growth were investigated by growing Arabidopsis thaliana anthocyanin production mutants (transparent testa) under limiting nitrogen and high light conditions. Inability to produce kaempferol or subsequent intermediate compounds by some transparent testa lines was correlated with less biomass accumulation in mature plants compared with wild-type control plants under all growth conditions tested. However, under both limiting nitrogen and high light chronic stress conditions, mutant lines defective in later steps of the anthocyanin production pathway produced the same or more biomass than wild-type plants. No difference in senescence between transparent testa and wild-type plants was found using chlorophyll catabolism and SAG12 expression measurements, and no mutants were impaired in the ability to remobilize nutrients from the vegetative to reproductive tissues. Moreover, the absence of anthocyanin and/or upstream flavonoids does not affect the ability of plants to respond to limiting nitrogen by reducing photosynthetic capacity. These results support a role for kaempferol and quercetin accumulation in normal plant growth and development. Further, the absence of anthocyanins has no effect on plant growth under the chronic stress conditions tested.

  12. Methylation mediated by an anthocyanin, O-methyltransferase, is involved in purple flower coloration in Paeonia.

    PubMed

    Du, Hui; Wu, Jie; Ji, Kui-Xian; Zeng, Qing-Yin; Bhuiya, Mohammad-Wadud; Su, Shang; Shu, Qing-Yan; Ren, Hong-Xu; Liu, Zheng-An; Wang, Liang-Sheng

    2015-11-01

    Anthocyanins are major pigments in plants. Methylation plays a role in the diversity and stability of anthocyanins. However, the contribution of anthocyanin methylation to flower coloration is still unclear. We identified two homologous anthocyanin O-methyltransferase (AOMT) genes from purple-flowered (PsAOMT) and red-flowered (PtAOMT) Paeonia plants, and we performed functional analyses of the two genes in vitro and in vivo. The critical amino acids for AOMT catalytic activity were studied by site-directed mutagenesis. We showed that the recombinant proteins, PsAOMT and PtAOMT, had identical substrate preferences towards anthocyanins. The methylation activity of PsAOMT was 60 times higher than that of PtAOMT in vitro. Interestingly, this vast difference in catalytic activity appeared to result from a single amino acid residue substitution at position 87 (arginine to leucine). There were significant differences between the 35S::PsAOMT transgenic tobacco and control flowers in relation to their chromatic parameters, which further confirmed the function of PsAOMT in vivo. The expression levels of the two homologous AOMT genes were consistent with anthocyanin accumulation in petals. We conclude that AOMTs are responsible for the methylation of cyanidin glycosides in Paeonia plants and play an important role in purple coloration in Paeonia spp.

  13. Gel permeation chromatography of anthocyanin pigments from Rosé cider and red wine.

    PubMed

    Shoji, T; Yanagida, A; Kanda, T

    1999-07-01

    Anthocyanin pigments from rosé cider and red wine, which is a sparkling wine made from apples, were separated by gel permeation chromatography (GPC) using a TSK-GEL Toyopearl HW-40 (F) column with a 6:4 mixture of acetone and 8 M urea (pH 2.0) as the eluent. Under this condition, all phenolic compounds containing monomeric anthocyanins (mainly, cyanidin-3-galactoside; Cyn-3-gal), oligomeric and polymeric anthocyanins, chlorogenic acid, catechin, epicatechin, procyanidin B2 (PB2), and procyanidin C1 (PC1) in the apples and rosé cider were found to elute according to molecular weight. Bleaching of the anthocyanin pigments by SO(2) was gradually effective in the fractions separated by GPC according to elution volume. In the case of rosé cider, the levels of Cyn-3-gal decreased markedly during fermentation and then decreased gradually during maturation. We confirmed that anthocyanin polymers are not detectable in apple juice; these polymers are produced during fermentation and maturation as determined by GPC. The polymeric anthocyanins from red wine could be separated by this method, too.

  14. Stabilization of natural colors and nutraceuticals: Inhibition of anthocyanin degradation in model beverages using polyphenols.

    PubMed

    Chung, Cheryl; Rojanasasithara, Thananunt; Mutilangi, William; McClements, David Julian

    2016-12-01

    Anthocyanins are widely used as natural colorants in foods, but they are highly susceptible to chemical degradation during storage leading to color fading. This study examined the potential of natural quillaja saponin and polyphenols (vanillin, epigallocatechin gallate, green tea extract, and protocatechualdehyde) at inhibiting color fading of anthocyanins in model beverages. The purple carrot anthocyanin (0.025%) in model beverages (citric acid, pH 3.0) containing l-ascorbic acid (0.050%) degraded with a first-order reaction rate during storage (40°C/7days in light). The addition of polyphenols (0.2%) delayed color fading, with the most notable improvement observed with green tea extract addition. The half-life for anthocyanin color fading increased from 2.9 to 6.7days with green tea extract. Fluorescence quenching measurements showed that the green tea extract contained components that interacted with anthocyanins probably through hydrophobic interactions. Overall, this study provides valuable information about enhancing the stability of anthocyanins in beverage systems using polyphenols. PMID:27374573

  15. Influence of temperature and preserving agents on the stability of cornelian cherries anthocyanins.

    PubMed

    Moldovan, Bianca; David, Luminiţa

    2014-01-01

    Cornelian cherry (Cornus mas L.) fruits are known for their significant amounts of anthocyanins which can be used as natural food colorants. The storage stability of anthocyanins from these fruit extracts, at different temperatures (2 °C, 25 °C and 75 °C), pH 3.02, in the presence of two of the most widely employed food preserving agents (sodium benzoate and potassium sorbate) was investigated. The highest stability was exhibited by the anthocyanin extract stored at 2 °C without any added preservative, with half-life and constant rate values of 1443.8 h and 0.48 × 10(-3) h(-1), respectively. The highest value of the degradation rate constant (82.76 × 10(-3)/h) was obtained in the case of anthocyanin extract stored at 75 °C without any added preservative. Experimental results indicate that the storage degradation of anthocyanins followed first-order reaction kinetics under each of the investigated conditions. In aqueous solution, the food preservatives used were found to have a slight influence on the anthocyanins' stability. PMID:24941341

  16. Genetic engineering of novel flower colour by suppression of anthocyanin modification genes in gentian.

    PubMed

    Nakatsuka, Takashi; Mishiba, Kei-ichiro; Kubota, Akiko; Abe, Yoshiko; Yamamura, Saburo; Nakamura, Noriko; Tanaka, Yoshikazu; Nishihara, Masahiro

    2010-02-15

    Ornamental gentian plants have vivid-blue flowers. The main factor contributing to the flower colour is the accumulation of a polyacylated delphinidin 'gentiodelphin' in their petals. Although in vitro studies proposed that acylation plays an important role in the stability and development of gentian blue colour, the in vivo stability of the polyacylated anthocyanin was not clearly demonstrated. Thus, to reveal the importance of anthocyanin modification, especially acylation, and to engineer new colours of gentian flowers, we used chimeric RNAi technology to produce transgenic gentian plants with downregulated anthocyanin 5,3'-aromatic acyltransferase (5/3'AT) and flavonoid 3',5'-hydroxylase (F3'5'H) activities, which are both essential enzymes for gentiodelphin biosynthesis. Two lines of flower colour-modified plants were obtained from fifteen transgenic gentian plants. Clone no. 1 exhibited a lilac flower colour and clone no. 15 exhibited pale-blue flowers. RNA gel blot analysis confirmed that both transgenic lines had markedly suppressed 5/3'AT transcripts, whereas clone no. 15 had fewer F3'5'H transcripts than clone no. 1 and untransformed control plants. HPLC analysis of anthocyanin compositions showed that downregulation of the 5/3'AT gene led to increased accumulation of non-acylated anthocyanins, as expected. These results demonstrated that genetic engineering to reduce the accumulation of polyacylated anthocyanins could cause modulations of flower colour.

  17. Antiproliferative and antioxidant properties of anthocyanin rich extracts from blueberry and blackcurrant juice.

    PubMed

    Diaconeasa, Zoriţa; Leopold, Loredana; Rugină, Dumitriţa; Ayvaz, Huseyin; Socaciu, Carmen

    2015-01-01

    The present study was aimed at evaluating the antiproliferative potential of anthocyanin-rich fractions (ARFs) obtained from two commercially available juices (blueberry and blackcurrant juices) on three tumor cell lines; B16F10 (murine melanoma), A2780 (ovarian cancer) and HeLa (cervical cancer). Individual anthocyanin determination, identification and quantification were done using HPLC-MS. Antioxidant activity of the juices was determined through different mechanism methods such as DPPH and ORAC. For biological testing, the juices were purified through C18 cartridges in order to obtain fractions rich in anthocyanins. The major anthocyanins identified were glycosylated cyanidin derivatives. The antiproliferative activity of the fractions was tested using the MTT assay. The antiproliferative potential of ARF was found to be associated with those bioactive molecules, anthocyanins due to their antioxidant potential. The results obtained indicated that both blueberry and blackcurrants are rich sources of antioxidants including anthocyanins and therefore these fruits are highly recommended for daily consumption to prevent numerous degenerative diseases.

  18. Physiological and genetic analysis of Arabidopsis thaliana anthocyanin biosynthesis mutants under chronic adverse environmental conditions

    PubMed Central

    Rothstein, Steven J.

    2013-01-01

    Anthocyanin production is a characteristic response of flowering plants to unfavourable environmental conditions. The potential roles of flavonoids and anthocyanins in plant growth were investigated by growing Arabidopsis thaliana anthocyanin production mutants (transparent testa) under limiting nitrogen and high light conditions. Inability to produce kaempferol or subsequent intermediate compounds by some transparent testa lines was correlated with less biomass accumulation in mature plants compared with wild-type control plants under all growth conditions tested. However, under both limiting nitrogen and high light chronic stress conditions, mutant lines defective in later steps of the anthocyanin production pathway produced the same or more biomass than wild-type plants. No difference in senescence between transparent testa and wild-type plants was found using chlorophyll catabolism and SAG12 expression measurements, and no mutants were impaired in the ability to remobilize nutrients from the vegetative to reproductive tissues. Moreover, the absence of anthocyanin and/or upstream flavonoids does not affect the ability of plants to respond to limiting nitrogen by reducing photosynthetic capacity. These results support a role for kaempferol and quercetin accumulation in normal plant growth and development. Further, the absence of anthocyanins has no effect on plant growth under the chronic stress conditions tested. PMID:23162120

  19. Deep sequencing of the Camellia chekiangoleosa transcriptome revealed candidate genes for anthocyanin biosynthesis.

    PubMed

    Wang, Zhong-Wei; Jiang, Cong; Wen, Qiang; Wang, Na; Tao, Yuan-Yuan; Xu, Li-An

    2014-03-15

    Camellia chekiangoleosa is an important species of genus Camellia. It provides high-quality edible oil and has great ornamental value. The flowers are big and red which bloom between February and March. Flower pigmentation is closely related to the accumulation of anthocyanin. Although anthocyanin biosynthesis has been studied extensively in herbaceous plants, little molecular information on the anthocyanin biosynthesis pathway of C. chekiangoleosa is yet known. In the present study, a cDNA library was constructed to obtain detailed and general data from the flowers of C. chekiangoleosa. To explore the transcriptome of C. chekiangoleosa and investigate genes involved in anthocyanin biosynthesis, a 454 GS FLX Titanium platform was used to generate an EST dataset. About 46,279 sequences were obtained, and 24,593 (53.1%) were annotated. Using Blast search against the AGRIS, 1740 unigenes were found homologous to 599 Arabidopsis transcription factor genes. Based on the transcriptome dataset, nine anthocyanin biosynthesis pathway genes (PAL, CHS1, CHS2, CHS3, CHI, F3H, DFR, ANS, and UFGT) were identified and cloned. The spatio-temporal expression patterns of these genes were also analyzed using quantitative real-time polymerase chain reaction. The study results not only enrich the gene resource but also provide valuable information for further studies concerning anthocyanin biosynthesis. PMID:24462969

  20. Anthocyanin profiling of Berberis lycium Royle berry and its bioactivity evaluation for its nutraceutical potential.

    PubMed

    Pradhan, Prakash Chandra; Saha, Supradip

    2016-02-01

    Berberis lycium Royle (Kashmal) belongs to Berberidaceae family and it has a small edible purple berry. It is grown wildly grown in Himalaya. The berry anthocyanins were characterised by HPLC coupled to a photodiode array (PDA) and mass spectrophotometer (MS) detectors. Twelve anthocyanins were identified in the purified extract of berberis berry. Two anthocyanins delphinidin-3-glucoside (35.3 %) and cyanidin-3-glucoside (47.2 %) were characterized as major components. Ten minor anthocyanins were Cyanidin-3-lathyroside (0.08 %), Cyanidin-3-rutinoside (0.53 %), Cyanidin-3-galactoside (1.62 %), Pelargonidin-3-pentoxilhexoside (2.26 %), Malvidin-3,5-dihexoside (4.21 %), Pelargonidin-hexoside (0.58 %), Pelargonidin- 3,5-diglucoside (1.05 %), Cyanidin-3,5-dihexoside (6.12 %), peonidin-3-rutinoside (0.77 %), pelargonidin-3-rutinoside (0.22 %). Apart from anthocyanins, six phenolics were also identified as chlorogenic acid, coumaric acid, caffeic acid, syringic acid, vanillic acid and quercetin. Antioxidant activity evaluated by DPPH assay revealed IC50 value of anthocyanin was 25.3 μg ml(-1). FRAP and CUPRAC assay also gave significant antioxidant activity. MTT assay gave the absorbance of 0.53 at 250 μg ml(-1). It may be concluded that the wild berry should be exploited as a source of nutraceuticals for its constitutive phenolics and its activity.

  1. Why some stems are red: cauline anthocyanins shield photosystem II against high light stress

    PubMed Central

    Gould, Kevin S.; Dudle, Dana A.; Neufeld, Howard S.

    2010-01-01

    Red-stemmed plants are extremely common, yet the functions of cauline anthocyanins are largely unknown. The possibility that photoabatement by anthocyanins in the periderm reduces the propensity for photoinhibition in cortical chlorenchyma was tested for Cornus stolonifera. Anthocyanins were induced in green stems exposed to full sunlight. PSII quantum yields (ФPSII) and photochemical quenching coefficients were depressed less in red than in green stems, both under a light ramp and after prolonged exposures to saturating white light. These differences were primarily attributable to the attenuation of PAR, especially green/yellow light, by anthocyanins. However, the red internodes also had less chlorophyll and higher carotenoid:chlorophyll ratios than the green, and when the anthocyanic periderm was removed, small differences in the ФPSII of the underlying chlorenchyma were retained. Thus, light screening by cauline anthocyanins is important, but is only part of a set of protective acclimations to high irradiance. Hourly measurements of ФPSII on established trees under natural daylight indicated a possible advantage of red versus green stems under sub-saturating diffuse, but not direct sunlight. To judge the wider applicability of the hypothesis, responses to high light were compared for red and green stems across five further unrelated species. There was a strong, linear, interspecific correlation between photoprotective advantage and anthocyanin concentration differences among red and green internodes. The photoprotective effect appears to be a widespread phenomenon. PMID:20400528

  2. Role of Anthocyanin-enriched Purple-fleshed Sweet Potato P40 in Colorectal Cancer Prevention

    PubMed Central

    Lim, Soyoung; Xu, Jianteng; Kim, Jaeyong; Chen, Tzu-Yu; Su, Xiaoyu; Standard, Joseph; Carey, Edward; Griffin, Jason; Herndon, Betty; Katz, Benjamin; Tomich, John; Wang, Weiqun

    2013-01-01

    Scope Anthocyanins, the natural pigments in plant foods, have been associated with cancer prevention. However, the content of anthocyanins in staple foods is typically low and the mechanisms by which they exert anti-cancer activity is not yet fully defined. Methods and results We selected an anthocyanin-enriched purple-fleshed sweet potato clone, P40, and investigated its potential anti-cancer effect in both in vitro cell culture and in vivo animal model. In addition to a high level of total phenolics and antioxidant capacity, P40 possesses a high content of anthocyanins at 7.5 mg/g dry matter. Treatment of human colonic SW480 cancer cells with P40 anthocyanin extracts at 0–40 μM of peonidin-3-glucoside equivalent resulted in a dose-dependent decrease in cell number due to cytostatic arrest of cell cycle at G1 phase but not cytotoxicity. Furthermore, dietary P40 at 10–30% significantly suppressed azoxymethane-induced formation of aberrant crypt foci in the colons of CF-1 mice in conjunction with, at least in part, a lesser proliferative PCNA and a greater apoptotic caspase-3 expression in the colon mucosal epithelial cells. Conclusion These observations, coupled with both in vitro and in vivo studies reported here, suggest anthocyanin-enriched sweet potato P40 may protect against colorectal cancer by inducing cell cycle arrest, anti-proliferative and apoptotic mechanisms. PMID:23784800

  3. Antiproliferative and Antioxidant Properties of Anthocyanin Rich Extracts from Blueberry and Blackcurrant Juice

    PubMed Central

    Diaconeasa, Zoriţa; Leopold, Loredana; Rugină, Dumitriţa; Ayvaz, Huseyin; Socaciu, Carmen

    2015-01-01

    The present study was aimed at evaluating the antiproliferative potential of anthocyanin-rich fractions (ARFs) obtained from two commercially available juices (blueberry and blackcurrant juices) on three tumor cell lines; B16F10 (murine melanoma), A2780 (ovarian cancer) and HeLa (cervical cancer). Individual anthocyanin determination, identification and quantification were done using HPLC-MS. Antioxidant activity of the juices was determined through different mechanism methods such as DPPH and ORAC. For biological testing, the juices were purified through C18 cartridges in order to obtain fractions rich in anthocyanins. The major anthocyanins identified were glycosylated cyanidin derivatives. The antiproliferative activity of the fractions was tested using the MTT assay. The antiproliferative potential of ARF was found to be associated with those bioactive molecules, anthocyanins due to their antioxidant potential. The results obtained indicated that both blueberry and blackcurrants are rich sources of antioxidants including anthocyanins and therefore these fruits are highly recommended for daily consumption to prevent numerous degenerative diseases. PMID:25622252

  4. Anthocyanin and other phenolic compounds in Ceylon gooseberry (Dovyalis hebecarpa) fruits.

    PubMed

    Bochi, Vivian Caetano; Godoy, Helena Teixeira; Giusti, M Monica

    2015-06-01

    Ceylon gooseberry is a deep-purple exotic berry that is being produced in Brazil with great market potential. This work aimed to determine major phenolic compounds in this specie by HPLC-PDA-ESI/MS. Samples were collected in two different seasons. Pulp and skin were analyzed separately. Non-acylated rutinoside derivatives of delphinidin (∼60-63%) and cyanidin (∼17-21%) were major anthocyanins tentatively identified. All anthocyanins had higher concentration in skin than in pulp (64-82 and 646-534mg of cyaniding-3-glucoside equivalents/100g skin and pulp, respectively). Moreover, anthocyanin profile changed between sampling dates (p<0.05). Mainly for delphinidin-3-rutinoside which could be a result of season variation. In this specie, non-anthocyanin polyphenols represent less than 35% of total extracted polyphenols. The tentative identification proposed a flavonol and three ellagitannins as major compounds of the non-anthocyanin phenolics fraction. Finally, anthocyanin is the major phenolic class in this fruit and its composition and content are significantly affected by season.

  5. Anthocyanins, antioxidative, and antimicrobial properties of American cranberry (Vaccinium macrocarpon Ait.) and their press cakes.

    PubMed

    Viskelis, P; Rubinskiene, M; Jasutiene, I; Sarkinas, A; Daubaras, R; Cesoniene, L

    2009-03-01

    Amounts of total phenolics, anthocyanins, and ascorbic acid in 4 American cranberry varieties harvested at 4 stages of maturity were measured. The larger amount of phenolic compounds was found in berries of "Black Veil" cultivar (504 mg/100 g) at II stage of maturity. Significantly larger amounts of anthocyanins were determined in the overripe berries of the cultivars "Ben Lear" and "Black Veil." The amount of ascorbic acid in berries increased during ripening from I to III stage, and slightly decreased in the overripe berries. The biggest quantities of ascorbic acid were found in the ripe berries of "Ben Lear" cultivar (15.8 mg/100 g). The distribution of anthocyanins pigments was determined by HPLC-UV/MS in mature berries. The composition of individual anthocyanins in berries was quite similar in all the studied cranberry cultivars. While skins of cranberries are rich in anthocyanins and other phenolic compounds, the extracts of the by-products of cranberries juice-berry cakes, were analyzed and obtained results were compared with the properties of extracts made from whole berries. The anthocyanins and total phenolics content, radical scavenging activity, antimicrobial activity of the whole berries, and their press cakes extracts were measured. All investigated extracts from berries and their press cakes showed good radical scavenging activity and revealed antimicrobial properties. It was found that Bacillus cereus (ATCC 10876) and Micrococcus luteus (ATCC 9341) were the most sensitive among 10 tested Gram-negative and Gram-positive bacteria.

  6. Methylation mediated by an anthocyanin, O-methyltransferase, is involved in purple flower coloration in Paeonia

    PubMed Central

    Du, Hui; Wu, Jie; Ji, Kui-Xian; Zeng, Qing-Yin; Bhuiya, Mohammad-Wadud; Su, Shang; Shu, Qing-Yan; Ren, Hong-Xu; Liu, Zheng-An; Wang, Liang-Sheng

    2015-01-01

    Anthocyanins are major pigments in plants. Methylation plays a role in the diversity and stability of anthocyanins. However, the contribution of anthocyanin methylation to flower coloration is still unclear. We identified two homologous anthocyanin O-methyltransferase (AOMT) genes from purple-flowered (PsAOMT) and red-flowered (PtAOMT) Paeonia plants, and we performed functional analyses of the two genes in vitro and in vivo. The critical amino acids for AOMT catalytic activity were studied by site-directed mutagenesis. We showed that the recombinant proteins, PsAOMT and PtAOMT, had identical substrate preferences towards anthocyanins. The methylation activity of PsAOMT was 60 times higher than that of PtAOMT in vitro. Interestingly, this vast difference in catalytic activity appeared to result from a single amino acid residue substitution at position 87 (arginine to leucine). There were significant differences between the 35S::PsAOMT transgenic tobacco and control flowers in relation to their chromatic parameters, which further confirmed the function of PsAOMT in vivo. The expression levels of the two homologous AOMT genes were consistent with anthocyanin accumulation in petals. We conclude that AOMTs are responsible for the methylation of cyanidin glycosides in Paeonia plants and play an important role in purple coloration in Paeonia spp. PMID:26208646

  7. Effect of ultrasound on the extraction of total anthocyanins from Purple Majesty potato.

    PubMed

    Mane, Shon; Bremner, David H; Tziboula-Clarke, Athina; Lemos, M Adília

    2015-11-01

    This study examined anthocyanin extraction using the application of ultrasound to raw freeze dried, microwaved and raw sliced Purple Majesty potato, a new pigmented potato variety rich in anthocyanins. A 20 kHz probe was used for the sonication at 3 different amplitudes (30%, 50% and 70%) and ethanol in water at different ratios (50:50 and 70:30 v/v) was used for the extraction. Anthocyanin extraction from raw freeze dried purple potato was optimal at an ethanol:water ratio (70:30; v/v) after 5 min of ultrasonication, while the least amount of anthocyanins was extracted from raw sliced potatoes. The application of microwaves (as a pre-treatment) before the UAE resulted in an increase in the amount of anthocyanins extracted and a decrease in the amount of solvent used. Analysis of variance showed that potato form, ultrasonication time, ultrasonication amplitude and solvent ratio as well as two and three way interactions between some of these factors had a very significant effect (p<0.000) on the amount of anthocyanins extracted.

  8. Enhancement of colour stability of anthocyanins in model beverages by gum arabic addition.

    PubMed

    Chung, Cheryl; Rojanasasithara, Thananunt; Mutilangi, William; McClements, David Julian

    2016-06-15

    This study investigated the potential of gum arabic to improve the stability of anthocyanins that are used in commercial beverages as natural colourants. The degradation of purple carrot anthocyanin in model beverage systems (pH 3.0) containing L-ascorbic acid proceeded with a first-order reaction rate during storage (40 °C for 5 days in light). The addition of gum arabic (0.05-5.0%) significantly enhanced the colour stability of anthocyanin, with the most stable systems observed at intermediate levels (1.5%). A further increase in concentration (>1.5%) reduced its efficacy due to a change in the conformation of the gum arabic molecules that hindered their exposure to the anthocyanins. Fluorescence quenching measurements showed that the anthocyanin could have interacted with the glycoprotein fractions of the gum arabic through hydrogen bonding, resulting in enhanced stability. Overall, this study provides valuable information about enhancing the stability of anthocyanins in beverage systems using natural ingredients.

  9. Multiple repressive mechanisms in the hippocampus during memory formation.

    PubMed

    Cho, Jun; Yu, Nam-Kyung; Choi, Jun-Hyeok; Sim, Su-Eon; Kang, SukJae Joshua; Kwak, Chuljung; Lee, Seung-Woo; Kim, Ji-il; Choi, Dong Il; Kim, V Narry; Kaang, Bong-Kiun

    2015-10-01

    Memory stabilization after learning requires translational and transcriptional regulations in the brain, yet the temporal molecular changes that occur after learning have not been explored at the genomic scale. We used ribosome profiling and RNA sequencing to quantify the translational status and transcript levels in the mouse hippocampus after contextual fear conditioning. We revealed three types of repressive regulations: translational suppression of ribosomal protein-coding genes in the hippocampus, learning-induced early translational repression of specific genes, and late persistent suppression of a subset of genes via inhibition of estrogen receptor 1 (ESR1/ERα) signaling. In behavioral analyses, overexpressing Nrsn1, one of the newly identified genes undergoing rapid translational repression, or activating ESR1 in the hippocampus impaired memory formation. Collectively, this study unveils the yet-unappreciated importance of gene repression mechanisms for memory formation.

  10. Targeted Transcriptional Repression in Bacteria Using CRISPR Interference (CRISPRi).

    PubMed

    Hawkins, John S; Wong, Spencer; Peters, Jason M; Almeida, Ricardo; Qi, Lei S

    2015-01-01

    Clustered regularly interspersed short palindromic repeats (CRISPR) interference (CRISPRi) is a powerful technology for sequence-specifically repressing gene expression in bacterial cells. CRISPRi requires only a single protein and a custom-designed guide RNA for specific gene targeting. In Escherichia coli, CRISPRi repression efficiency is high (~300-fold), and there are no observable off-target effects. The method can be scaled up as a general strategy for the repression of many genes simultaneously using multiple designed guide RNAs. Here we provide a protocol for efficient guide RNA design, cloning, and assay of the CRISPRi system in E. coli. In principle, this protocol can be used to construct CRISPRi systems for gene repression in other species of bacteria.

  11. Chemoprevention of esophageal cancer with black raspberries, their component anthocyanins, and a major anthocyanin metabolite, protocatechuic acid.

    PubMed

    Peiffer, Daniel S; Zimmerman, Noah P; Wang, Li-Shu; Ransom, Benjamin W S; Carmella, Steven G; Kuo, Chieh-Ti; Siddiqui, Jibran; Chen, Jo-Hsin; Oshima, Kiyoko; Huang, Yi-Wen; Hecht, Stephen S; Stoner, Gary D

    2014-06-01

    Diets containing either freeze-dried black raspberries (BRBs) or their polyphenolic anthocyanins (ACs) have been shown to inhibit the development of N-nitrosomethylbenzylamine (NMBA)-induced esophageal cancer in rats. The present study was conducted to determine whether PCA, a major microbial metabolite of black raspberry (BRB) ACs, also prevents NMBA-induced esophageal cancer in rats. F344 rats were injected with NMBA three times a week for 5 weeks and then fed control or experimental diets containing 6.1% BRBs, an anthocyanin (AC)-enriched fraction derived from BRBs, or protocatechuic acid (PCA). Animals were exsanguinated at weeks 15, 25, and 35 to quantify the development of preneoplastic lesions and tumors in the esophagus, and to relate this to the expression of inflammatory biomarkers. At weeks 15 and 25, all experimental diets were equally effective in reducing NMBA-induced esophageal tumorigenesis, as well as in reducing the expression of pentraxin-3 (PTX3), a cytokine produced by peripheral blood mononuclear cells in response to interleukin (IL)-1β and TNF-α. All experimental diets were also active at reducing tumorigenesis at week 35; however, the BRB diet was significantly more effective than the AC and PCA diets. Furthermore, all experimental diets inhibited inflammation in the esophagus via reducing biomarker (COX-2, iNOS, p-NF-κB, and sEH) and cytokine (PTX3) expression. Overall, our data suggest that BRBs, their component ACs, and PCA inhibit NMBA-induced esophageal tumorigenesis, at least in part, by their inhibitory effects on genes associated with inflammation.

  12. Influences of organically and conventionally grown strawberry cultivars on anthocyanins content and color in purees and low-sugar jams.

    PubMed

    Bursać Kovačević, Danijela; Putnik, Predrag; Dragović-Uzelac, Verica; Vahčić, Nada; Babojelić, Martina Skendrović; Levaj, Branka

    2015-08-15

    The objective of this study was to detect influences of cultivar, cultivation and processing on anthocyanin content and color in purees and low-sugar jams produced from strawberry cultivars (Elsanta, Maya, Marmolada, Queen Elisa), grown under conventional and organic cultivation. Color was determined by CIELab values while anthocyanins were quantified by HPLC-UV/VIS-PDA. Queen Elisa was the best cultivar for processing as it had highest total anthocyanin content (TAC) that was well preserved in processing. On average, processing purees to jams decreased TAC for 28% where pelargonidin-3-glucoside revealed most noticeable loss (53%) and cyanidin-3-rutinoside was best preserved in processing. Obtained results indicated that measurement of colorimetric parameters are strongly correlated with content of anthocyanins. In other words, loss of anthocyanins during processing was accompanied by noticeable decrease in lightness, red/yellow color and total color change. Results showed that change of color is useful predictor for estimating anthocyanins in strawberry purees and jams.

  13. The food matrix affects the anthocyanin profile of fortified egg and dairy matrices during processing and in vitro digestion.

    PubMed

    Pineda-Vadillo, Carlos; Nau, Françoise; Guerin-Dubiard, Catherin; Jardin, Julien; Lechevalier, Valérie; Sanz-Buenhombre, Marisa; Guadarrama, Alberto; Tóth, Tamás; Csavajda, Éva; Hingyi, Hajnalka; Karakaya, Sibel; Sibakov, Juhani; Capozzi, Francesco; Bordoni, Alessandra; Dupont, Didier

    2017-01-01

    The aim of the present study was to understand to what extent the inclusion of anthocyanins into dairy and egg matrices could affect their stability after processing and their release and solubility during digestion. For this purpose, individual and total anthocyanin content of four different enriched matrices, namely custard dessert, milkshake, pancake and omelettete, was determined after their manufacturing and during in vitro digestion. Results showed that anthocyanin recovery after processing largely varied among matrices, mainly due to the treatments applied and the interactions developed with other food components. In terms of digestion, the present study showed that the inclusion of anthocyanins into food matrices could be an effective way to protect them against intestinal degradation, and also the incorporation of anthocyanins into matrices with different compositions and structures could represent an interesting and effective method to control the delivery of anthocyanins within the different compartments of the digestive tract. PMID:27507502

  14. The food matrix affects the anthocyanin profile of fortified egg and dairy matrices during processing and in vitro digestion.

    PubMed

    Pineda-Vadillo, Carlos; Nau, Françoise; Guerin-Dubiard, Catherin; Jardin, Julien; Lechevalier, Valérie; Sanz-Buenhombre, Marisa; Guadarrama, Alberto; Tóth, Tamás; Csavajda, Éva; Hingyi, Hajnalka; Karakaya, Sibel; Sibakov, Juhani; Capozzi, Francesco; Bordoni, Alessandra; Dupont, Didier

    2017-01-01

    The aim of the present study was to understand to what extent the inclusion of anthocyanins into dairy and egg matrices could affect their stability after processing and their release and solubility during digestion. For this purpose, individual and total anthocyanin content of four different enriched matrices, namely custard dessert, milkshake, pancake and omelettete, was determined after their manufacturing and during in vitro digestion. Results showed that anthocyanin recovery after processing largely varied among matrices, mainly due to the treatments applied and the interactions developed with other food components. In terms of digestion, the present study showed that the inclusion of anthocyanins into food matrices could be an effective way to protect them against intestinal degradation, and also the incorporation of anthocyanins into matrices with different compositions and structures could represent an interesting and effective method to control the delivery of anthocyanins within the different compartments of the digestive tract.

  15. Overexpressing CAPRICE and GLABRA3 did not change the anthocyanin content of tomato (solanum lycopersicum) fruit peel

    PubMed Central

    Wada, Takuji; Onishi, Mio; Kunihiro, Asuka; Tominaga-Wada, Rumi

    2015-01-01

    In Arabidopsis thaliana, the R3-type MYB transcription factor CAPRICE (CPC) and bHLH transcription factor GLABRA3 (GL3) cooperatively regulate epidermal cell differentiation. CPC and GL3 are involved in root-hair differentiation, trichome initiation and anthocyanin biosynthesis in Arabidopsis epidermal cells. Previously, we showed that CPC and GL3 also influence anthocyanin accumulation in tomato. Introduction of 35S::CPC into tomato significantly inhibits anthocyanin accumulation in cotyledons, leaves and stems. In contrast, introduction of GL3::GL3 strongly enhances anthocyanin accumulation in cotyledons, leaves and stems of tomato. In this study, we investigated the effect of CPC and GL3 on anthocyanin accumulation in the epidermis of tomato fruit. Unlike the results with vegetative tissues, overexpression of CPC and GL3 did not influence anthocyanin biosynthesis in tomato fruit peel. PMID:26039466

  16. Organic acid mediated repression of sugar utilization in rhizobia.

    PubMed

    Iyer, Bhagya; Rajput, Mahendrapal Singh; Jog, Rahul; Joshi, Ekta; Bharwad, Krishna; Rajkumar, Shalini

    2016-11-01

    Rhizobia are a class of symbiotic diazotrophic bacteria which utilize C4 acids in preference to sugars and the sugar utilization is repressed as long as C4 acids are present. This can be manifested as a diauxie when rhizobia are grown in the presence of a sugar and a C4 acid together. Succinate, a C4 acid is known to repress utilization of sugars, sugar alcohols, hydrocarbons, etc by a mechanism termed as Succinate Mediated Catabolite Repression (SMCR). Mechanism of catabolite repression determines the hierarchy of carbon source utilization in bacteria. Though the mechanism of catabolite repression has been well studied in model organisms like E. coli, B. subtilis and Pseudomonas sp., mechanism of SMCR in rhizobia has not been well elucidated. C4 acid uptake is important for effective symbioses while mutation in the sugar transport and utilization genes does not affect symbioses. Deletion of hpr and sma0113 resulted in the partial relief of SMCR of utilization of galactosides like lactose, raffinose and maltose in the presence of succinate. However, no such regulators governing SMCR of glucoside utilization have been identified till date. Though rhizobia can utilize multitude of sugars, high affinity transporters for many sugars are yet to be identified. Identifying high affinity sugar transporters and studying the mechanism of catabolite repression in rhizobia is important to understand the level of regulation of SMCR and the key regulators involved in SMCR. PMID:27664739

  17. Nero d'Avola and Perricone cultivars: determination of polyphenols, flavonoids and anthocyanins in grapes and wines.

    PubMed

    Gervasi, Teresa; Oliveri, Francesca; Gottuso, Valentina; Squadrito, Margherita; Bartolomeo, Giovanni; Cicero, Nicola; Dugo, Giacomo

    2016-10-01

    In 2011 vintage, the evolution of monomer and total anthocyanins, as well as of total flavonoids and polyphenols of grapes and wine of Nero d'Avola and Perricone, varieties cultivated in Sicily, was studied. Anthocyanin profiles are commonly used for grapevine cultivar identification because it is currently accepted that this trait is closely related to their genetic characteristics. The concentration of Nero d'Avola and Perricone anthocyanins was determined by HPLC-DAD. PMID:27109122

  18. FEN2: a gene implicated in the catabolite repression-mediated regulation of ergosterol biosynthesis in yeast.

    PubMed

    Marcireau, C; Joets, J; Pousset, D; Guilloton, M; Karst, F

    1996-05-01

    We have isolated and characterized a pleiotropic recessive mutation. fen2-1, that causes resistance to fenpropimorph and a low level of ergosterol in Saccharomyces cerevisiae. Ergosterol synthesis in the mutant strain was 5.5-fold slower than in the wild type; however, in vitro assays of the enzymes involved in ergosterol biosynthesis could not account for this low rate in the mutant. The mutant phenotype was expressed only in media exerting both carbon and nitrogen catabolite repression. To our knowledge, this is the first locus in yeast that reveals a concerted regulation between different pathways (carbon and nitrogen catabolite repression and/or general control of amino acid biosynthesis and ergosterol biosynthesis). The yeast gene FEN2 has been isolated and contains an open reading frame (ORF) of 512 codons. This ORF was found to be identical to YCR28C of chromosome III. A possible function of the FEN2 gene product in yeast is discussed.

  19. The DDX6-4E-T interaction mediates translational repression and P-body assembly.

    PubMed

    Kamenska, Anastasiia; Simpson, Clare; Vindry, Caroline; Broomhead, Helen; Bénard, Marianne; Ernoult-Lange, Michèle; Lee, Benjamin P; Harries, Lorna W; Weil, Dominique; Standart, Nancy

    2016-07-27

    4E-Transporter binds eIF4E via its consensus sequence YXXXXLΦ, shared with eIF4G, and is a nucleocytoplasmic shuttling protein found enriched in P-(rocessing) bodies. 4E-T inhibits general protein synthesis by reducing available eIF4E levels. Recently, we showed that 4E-T bound to mRNA however represses its translation in an eIF4E-independent manner, and contributes to silencing of mRNAs targeted by miRNAs. Here, we address further the mechanism of translational repression by 4E-T by first identifying and delineating the interacting sites of its major partners by mass spectrometry and western blotting, including DDX6, UNR, unrip, PAT1B, LSM14A and CNOT4. Furthermore, we document novel binding between 4E-T partners including UNR-CNOT4 and unrip-LSM14A, altogether suggesting 4E-T nucleates a complex network of RNA-binding protein interactions. In functional assays, we demonstrate that joint deletion of two short conserved motifs that bind UNR and DDX6 relieves repression of 4E-T-bound mRNA, in part reliant on the 4E-T-DDX6-CNOT1 axis. We also show that the DDX6-4E-T interaction mediates miRNA-dependent translational repression and de novo P-body assembly, implying that translational repression and formation of new P-bodies are coupled processes. Altogether these findings considerably extend our understanding of the role of 4E-T in gene regulation, important in development and neurogenesis. PMID:27342281

  20. The effect of solvents on the stabilities (color and Fe) of anthocyanin isolated from the red-color-melinjo peels

    NASA Astrophysics Data System (ADS)

    Tarmizi, Ermiziar; Lalasari, Latifa Hanum; Saragih, Raskita

    2015-12-01

    Anthocyanin from the red-color-melinjo peels could be isolated using a polar solvent (ethanol) [ermiziar, 2010]. The amount of hydrocarbons in the structure of anthocyanin might cause that anthocyanin could be isolated using a non polar solvent. The purpose of research is to isolate anthocyanin using non polar solvents (hexane and petroleum ether) with maceration steps for 24 hours and separate solvents using rotary evaporator equipment. The stability of anthocyanin could be observed every week (1,2,3 and 4 weeks) in various environmental conditions (with or without light in refrigerator and open or closed storage). The characterization of anthocyanin was analyzed with visual (physic photo) and or using equipments such as Fourier Transform Infrared Spectroscopy (FTIR) for determining functional groups, Ultraviolet-Visible Spectroscopy (UV/Vis) with 500-550 nm wavelengths for deciding absorption of anthocyanin and atomic absorption spectroscopy (AAS) for analyzing Fe element. The result showed that anthocyanin isolation with hexane solvent has yield higher than petroleum eter solvent. From the results of physic observation for 4 weeks looked that there are changing colors of samples significant after 3 and 4 weeks in cooler with or without light. The stability of anthocyanin color was the best on the storage time until 2 weeks using hexane solvent in refrigerator and closed condition that it has absorption of 0.6740 with 500 nm wavelengths and Fe concentration 6.29 ppm.

  1. Effect of cultivar on phenolic levels, anthocyanin composition, and antioxidant properties in purple basil (Ocimum basilicum L.).

    PubMed

    Flanigan, Patrick M; Niemeyer, Emily D

    2014-12-01

    In this study, we determined the effect of cultivar on total and individual anthocyanin concentrations and phenolic acid levels in eight purple basil varieties and examined the relationship between anthocyanin content, phenolic acid composition, and antioxidant properties. Cultivar had a significant influence on total anthocyanin concentrations as well as individual anthocyanin composition. The four major basil anthocyanins (labelled A-D) were quantified and cultivar had a statistically significant effect on anthocyanins B (p<0.01), C (p<0.01), and D (p<0.01), but not on anthocyanin A (p=0.94). Cultivar did not have a significant effect on total phenolic levels, although it did influence the concentration of some individual phenolic acids, including caftaric (p=0.03) and chicoric (p=0.04) acids. Although total phenolic and anthocyanin levels correlated with measured FRAP antioxidant capacities, for some cultivars the individual phenolic acid and anthocyanin composition was also an important factor affecting the antioxidant properties. PMID:24996365

  2. The effect of solvents on the stabilities (color and Fe) of anthocyanin isolated from the red-color-melinjo peels

    SciTech Connect

    Tarmizi, Ermiziar E-mail: ermitarmizi@gmail.com; Saragih, Raskita; Lalasari, Latifa Hanum E-mail: lati003@lipi.go.id

    2015-12-29

    Anthocyanin from the red-color-melinjo peels could be isolated using a polar solvent (ethanol) [ermiziar, 2010]. The amount of hydrocarbons in the structure of anthocyanin might cause that anthocyanin could be isolated using a non polar solvent. The purpose of research is to isolate anthocyanin using non polar solvents (hexane and petroleum ether) with maceration steps for 24 hours and separate solvents using rotary evaporator equipment. The stability of anthocyanin could be observed every week (1,2,3 and 4 weeks) in various environmental conditions (with or without light in refrigerator and open or closed storage). The characterization of anthocyanin was analyzed with visual (physic photo) and or using equipments such as Fourier Transform Infrared Spectroscopy (FTIR) for determining functional groups, Ultraviolet–Visible Spectroscopy (UV/Vis) with 500-550 nm wavelengths for deciding absorption of anthocyanin and atomic absorption spectroscopy (AAS) for analyzing Fe element. The result showed that anthocyanin isolation with hexane solvent has yield higher than petroleum eter solvent. From the results of physic observation for 4 weeks looked that there are changing colors of samples significant after 3 and 4 weeks in cooler with or without light. The stability of anthocyanin color was the best on the storage time until 2 weeks using hexane solvent in refrigerator and closed condition that it has absorption of 0.6740 with 500 nm wavelengths and Fe concentration 6.29 ppm.

  3. Three independent signalling pathways repress motility in Pseudomonas fluorescens F113.

    PubMed

    Navazo, Ana; Barahona, Emma; Redondo-Nieto, Miguel; Martínez-Granero, Francisco; Rivilla, Rafael; Martín, Marta

    2009-07-01

    Motility is one of the most important traits for rhizosphere colonization by pseudomonads. Despite this importance, motility is severely repressed in the rhizosphere-colonizing strain Pseudomonas fluorescens F113. This bacterium is unable to swarm under laboratory conditions and produce relatively small swimming haloes. However, phenotypic variants with the ability to swarm and producing swimming haloes up to 300% larger than the wild-type strain, arise during rhizosphere colonization. These variants harbour mutations in the genes encoding the GacA/GacS two-component system and in other genes. In order to identify genes and pathways implicated in motility repression, we have used generalized mutagenesis with transposons. Analysis of the mutants has shown that besides the Gac system, the Wsp system and the sadB gene, which have been previously implicated in cyclic di-GMP turnover, are implicated in motility repression: mutants in the gacS, sadB or wspR genes can swarm and produce swimming haloes larger than the wild-type strain. Epistasis analysis has shown that the pathways defined by each of these genes are independent, because double and triple mutants show an additive phenotype. Furthermore, GacS, SadB and WspR act at different levels. Expression of the fleQ gene, encoding the master regulator of flagella synthesis is higher in the gacS(-) and sadB(-) backgrounds than in the wild-type strain and this differential expression is reflected by a higher secretion of the flagellin protein FliC. Conversely, no differences in fleQ expression or FliC secretion were observed between the wild-type strain and the wspR(-) mutant.

  4. Effects of concentration prior to cold-stabilization on anthocyanin stability in concord grape juice.

    PubMed

    Alongi, Kristin S; Padilla-Zakour, Olga I; Sacks, Gavin L

    2010-11-10

    The color of Concord grape juice produced by concentration before cold-stabilization and detartration (direct-to-concentrate, DTC) was compared to juice produced via cold-stabilization prior to concentration (standard concentrate, SC) and evaluated by several metrics. Using the Boulton copigmentation assay, the majority of the absorbance at 520 nm in bottled SC juice (72%) was due to monomeric anthocyanins. Following reconstitution, DTC juice had a 63% greater absorbance at 520 nm than SC juice. A significant loss of anthocyanins was observed using a paired t test during cold-stabilization of single-strength juice during SC processing (mean loss: 79 mg/L as cyanidin-3-glucoside, 23% of total anthocyanins), while no significant loss of anthocyanins or change in other color metrics was observed during cold-stabilization of DTC concentrate. The concentration of anthocyanins in the SC bitartrate crystals was 0.80% w/w compared to 0.13% w/w in the DTC bitartrate crystals. Between DTC and SC, no difference in copigmentation was observed in cold-stabilized concentrate or reconstituted juice, indicating that the increased stability of anthocyanins could not be credited to greater copigmentation in DTC during detartration. HPLC analyses indicated that anthocyanin species with higher pKh and thus proportionally greater flavylium ion concentration at juice pH are preferentially lost during SC processing. The proportional changes in color metrics during shelf life stability testing (0-16 weeks, 2-30 °C) were not significantly different between SC and DTC juices.

  5. Stabilisation of strawberry (Fragaria x ananassa Duch.) anthocyanins by different pectins.

    PubMed

    Buchweitz, M; Speth, M; Kammerer, D R; Carle, R

    2013-12-01

    The objective of the present study was to evaluate the effects of different pectins on strawberry anthocyanins in viscous model solutions at pH 3.0. For this purpose, low esterified amidated, low and high methyl esterified citrus and apple pectins, and a sugar beet pectin (SBP), respectively, were added to strawberry extracts. The latter were predominantly composed of pelargonidin-glycosides, containing either reduced (E-1) or original amounts of non-anthocyanin phenolics (E-2). Model systems were stored for 18 weeks at 20±0.5 °C protected from light, and anthocyanins were quantitated in regular intervals by HPLC-DAD analyses. Half-life (t1/2) and destruction (D) values were calculated based on first-order kinetics. Generally, significant differences in pigment retention could be ascribed to differing pectin sources, while variation in the degree of esterification and amidation, respectively, had negligible effects. Compared to systems without added pectin, apple pectins and SPB enhanced anthocyanin stability moderately, while stabilising effects of citrus pectins were poor or even imperceptible. Generally, the amount of non-anthocyanin phenolics and the addition of citrate did not markedly affect anthocyanin stability. However, pectins had no influence on total phenolic contents (Folin-Ciocalteu assay) and antioxidant capacities (FRAP and TEAC assay) of strawberry phenolics over time. For pelargonidin-3-glucoside and -rutinoside largely consistent stabilities were found in all model systems. In contrast, pelargonidin-3-malonylglucoside was less stable in the blank, and stabilisation by pectins was always negligible. The findings of the present study are contrary to results reported previously for the stabilisation of cyanidin- and delphinidin-glycosides in similar model systems prepared with black currant extracts, indicating a high impact of the number of hydroxyl groups in the anthocyanin B-ring.

  6. New insights into the bioavailability of red raspberry anthocyanins and ellagitannins.

    PubMed

    Ludwig, Iziar A; Mena, Pedro; Calani, Luca; Borges, Gina; Pereira-Caro, Gema; Bresciani, Letizia; Del Rio, Daniele; Lean, Michael E J; Crozier, Alan

    2015-12-01

    Red raspberries, containing ellagitannins and cyanidin-based anthocyanins, were fed to volunteers and metabolites appearing in plasma and urine were analysed by UHPLC-MS. Anthocyanins were not absorbed to any extent with sub nmol/L concentrations of cyanidin-3-O-glucoside and a cyanidin-O-glucuronide appearing transiently in plasma. Anthocyanins excreted in urine corresponded to 0.007% of intake. More substantial amounts of phase II metabolites of ferulic acid and isoferulic acid, along with 4'-hydroxyhippuric acid, potentially originating from pH-mediated degradation of cyanidin in the proximal gastrointestinal tract, appeared in urine and also plasma where peak concentrations were attained 1-1.5h after raspberry intake. Excretion of 18 anthocyanin-derived metabolites corresponded to 15.0% of intake, a figure substantially higher than obtained in other anthocyanin feeding studies. Ellagitannins pass from the small to the large intestine where the colonic microbiota mediate their conversion to urolithins A and B which appeared in plasma and were excreted almost exclusively as sulfate and glucuronide metabolites. The urolithin metabolites persisted in the circulatory system and were excreted in urine for much longer periods of time than the anthocyanin metabolites although their overall urinary recovery was lower at 7.0% of intake. It is events originating in the proximal and distal gastrointestinal tract, and subsequent phase II metabolism, that play an important role in the bioavailability of both anthocyanins and ellagitannins and it is their metabolites which appear in the circulatory system, that are key to elucidating the mode of action(s) underlying the protective effects of these compounds on human health.

  7. Effects of climatic conditions and soil properties on Cabernet Sauvignon berry growth and anthocyanin profiles.

    PubMed

    Cheng, Guo; He, Yan-Nan; Yue, Tai-Xin; Wang, Jun; Zhang, Zhen-Wen

    2014-01-01

    Climatic conditions and soil type have significant influence on grape ripening and wine quality. The reported study was conducted in two "Cabernet Sauvignon (Vitis vinifera L.V)" vineyards located in Xinjiang, a semiarid wine-producing region of China during two vintages (2011 and 2012). The results indicate that soil and climate affected berry growth and anthocyanin profiles. These two localities were within a distance of 5 km from each other and had soils of different physical and chemical composition. For each vineyard, the differences of anthocyanin concentrations, and parameters concerning berry growth and composition between the two years could be explained by different climatic conditions. Soil effect was studied by investigation of differences in berry composition and anthocyanin profiles between the two vineyards in the same year, which could be explained mainly by the different soil properties, vine water and nitrogen status. Specifically, the soils with less water and organic matter produced looser clusters, heavier berry skins and higher TSS, which contributed to the excellent performance of grapes. Compared with 2011, the increases in anthocyanin concentrations for each vineyard in 2012 could be attributed to smaller number of extreme temperature (>35 °C) days and rainfall, lower vine water status and N level. The explanation for higher anthocyanin concentrations in grape skins from the soils with less water and organic matter could be the vine status differences, lighter berry weight and heavier skin weight at harvest. In particular, grapes from the soils with less water and organic matter had higher levels of 3'5'-substituded, O-methylated and acylated anthocyanins, which represented a positive characteristic conferring more stable pigmentation to the corresponding wine in the future. The present work clarifies the effects of climate and soil on berry growth and anthocyanin profiles, thus providing guidance for production of high-quality wine grapes

  8. Effects of climatic conditions and soil properties on Cabernet Sauvignon berry growth and anthocyanin profiles.

    PubMed

    Cheng, Guo; He, Yan-Nan; Yue, Tai-Xin; Wang, Jun; Zhang, Zhen-Wen

    2014-09-02

    Climatic conditions and soil type have significant influence on grape ripening and wine quality. The reported study was conducted in two "Cabernet Sauvignon (Vitis vinifera L.V)" vineyards located in Xinjiang, a semiarid wine-producing region of China during two vintages (2011 and 2012). The results indicate that soil and climate affected berry growth and anthocyanin profiles. These two localities were within a distance of 5 km from each other and had soils of different physical and chemical composition. For each vineyard, the differences of anthocyanin concentrations, and parameters concerning berry growth and composition between the two years could be explained by different climatic conditions. Soil effect was studied by investigation of differences in berry composition and anthocyanin profiles between the two vineyards in the same year, which could be explained mainly by the different soil properties, vine water and nitrogen status. Specifically, the soils with less water and organic matter produced looser clusters, heavier berry skins and higher TSS, which contributed to the excellent performance of grapes. Compared with 2011, the increases in anthocyanin concentrations for each vineyard in 2012 could be attributed to smaller number of extreme temperature (>35 °C) days and rainfall, lower vine water status and N level. The explanation for higher anthocyanin concentrations in grape skins from the soils with less water and organic matter could be the vine status differences, lighter berry weight and heavier skin weight at harvest. In particular, grapes from the soils with less water and organic matter had higher levels of 3'5'-substituded, O-methylated and acylated anthocyanins, which represented a positive characteristic conferring more stable pigmentation to the corresponding wine in the future. The present work clarifies the effects of climate and soil on berry growth and anthocyanin profiles, thus providing guidance for production of high-quality wine grapes

  9. mRNA Targeting to Endoplasmic Reticulum Precedes Ago Protein Interaction and MicroRNA (miRNA)-mediated Translation Repression in Mammalian Cells.

    PubMed

    Barman, Bahnisikha; Bhattacharyya, Suvendra N

    2015-10-01

    MicroRNA (miRNA) binds to the 3'-UTR of its target mRNAs to repress protein synthesis. Extensive research was done to understand the mechanism of miRNA-mediated repression in animal cells. Considering the progress in understanding the mechanism, information about the subcellular sites of miRNA-mediated repression is surprisingly limited. In this study, using an inducible expression system for an miRNA target message, we have delineated how a target mRNA passes through polysome association and Ago2 interaction steps on rough endoplasmic reticulum (ER) before the miRNA-mediated repression sets in. From this study, de novo formed target mRNA localization to the ER-bound polysomes manifested as the earliest event, which is followed by Ago2 micro-ribonucleoprotein binding, and translation repression of target message. Compartmentalization of this process to rough ER membrane ensures enrichment of miRNA-targeted messages and micro-ribonucleoprotein components on ER upon reaching a steady state. PMID:26304123

  10. mRNA Targeting to Endoplasmic Reticulum Precedes Ago Protein Interaction and MicroRNA (miRNA)-mediated Translation Repression in Mammalian Cells.

    PubMed

    Barman, Bahnisikha; Bhattacharyya, Suvendra N

    2015-10-01

    MicroRNA (miRNA) binds to the 3'-UTR of its target mRNAs to repress protein synthesis. Extensive research was done to understand the mechanism of miRNA-mediated repression in animal cells. Considering the progress in understanding the mechanism, information about the subcellular sites of miRNA-mediated repression is surprisingly limited. In this study, using an inducible expression system for an miRNA target message, we have delineated how a target mRNA passes through polysome association and Ago2 interaction steps on rough endoplasmic reticulum (ER) before the miRNA-mediated repression sets in. From this study, de novo formed target mRNA localization to the ER-bound polysomes manifested as the earliest event, which is followed by Ago2 micro-ribonucleoprotein binding, and translation repression of target message. Compartmentalization of this process to rough ER membrane ensures enrichment of miRNA-targeted messages and micro-ribonucleoprotein components on ER upon reaching a steady state.

  11. Flower color patterning in pansy (Viola × wittrockiana Gams.) is caused by the differential expression of three genes from the anthocyanin pathway in acyanic and cyanic flower areas.

    PubMed

    Li, Qin; Wang, Jian; Sun, Hai-Yan; Shang, Xiao

    2014-11-01

    The petals of pansy (Viola × wittrockiana Gams.) 'Mengdie' exhibit a cyanic blotched pigmentation pattern. The accumulation of anthocyanins, cyanidin and delphinidin, was detected in the upper epidermal cells of the cyanic blotches. In order to elucidate the mechanism by which cyanic blotches are formed in pansy petal, the expression level of genes involved in anthocyanin synthesis was measured and compared between cyanic blotches and acyanic areas of the flower. The use of primers in conserved regions allowed the successful isolation of six cDNA clones encoding putative anthocyanin enzymes from pansy petals. The clones isolated encoded chalcone synthase (CHS), chalcone isomerase (CHI), flavanone 3-hydroxylase (F3H), flavonoid 3'-hydroxylase (F3'H), dihydroflavonol 4-reductase (DFR) and anthocyanidin synthase (ANS). The transcription patterns of seven genes (VwCHS, VwCHI, VwF3H, VwF3'H, VwDFR, VwF3'5'H, and VwANS) in cyanic blotches and acyanic areas of the petals at seven stages of flower development were determined by real-time quantitative PCR. Transcription of VwF3'5'H, VwDFR and VwANS was significantly increased in cyanic blotches at stages III-V of flower development, implicating these genes in the pigmentation of Viola × wittrockiana Gams. petals.

  12. Flower color patterning in pansy (Viola × wittrockiana Gams.) is caused by the differential expression of three genes from the anthocyanin pathway in acyanic and cyanic flower areas.

    PubMed

    Li, Qin; Wang, Jian; Sun, Hai-Yan; Shang, Xiao

    2014-11-01

    The petals of pansy (Viola × wittrockiana Gams.) 'Mengdie' exhibit a cyanic blotched pigmentation pattern. The accumulation of anthocyanins, cyanidin and delphinidin, was detected in the upper epidermal cells of the cyanic blotches. In order to elucidate the mechanism by which cyanic blotches are formed in pansy petal, the expression level of genes involved in anthocyanin synthesis was measured and compared between cyanic blotches and acyanic areas of the flower. The use of primers in conserved regions allowed the successful isolation of six cDNA clones encoding putative anthocyanin enzymes from pansy petals. The clones isolated encoded chalcone synthase (CHS), chalcone isomerase (CHI), flavanone 3-hydroxylase (F3H), flavonoid 3'-hydroxylase (F3'H), dihydroflavonol 4-reductase (DFR) and anthocyanidin synthase (ANS). The transcription patterns of seven genes (VwCHS, VwCHI, VwF3H, VwF3'H, VwDFR, VwF3'5'H, and VwANS) in cyanic blotches and acyanic areas of the petals at seven stages of flower development were determined by real-time quantitative PCR. Transcription of VwF3'5'H, VwDFR and VwANS was significantly increased in cyanic blotches at stages III-V of flower development, implicating these genes in the pigmentation of Viola × wittrockiana Gams. petals. PMID:25270164

  13. Arbuscular mycorrhizal fungi and plant growth-promoting pseudomonads increases anthocyanin concentration in strawberry fruits (Fragaria x ananassa var. Selva) in conditions of reduced fertilization.

    PubMed

    Lingua, Guido; Bona, Elisa; Manassero, Paola; Marsano, Francesco; Todeschini, Valeria; Cantamessa, Simone; Copetta, Andrea; D'Agostino, Giovanni; Gamalero, Elisa; Berta, Graziella

    2013-08-06

    Anthocyanins are a group of common phenolic compounds in plants. They are mainly detected in flowers and fruits, are believed to play different important roles such as in the attraction of animals and seed dispersal, and also in the increase of the antioxidant response in tissues directly or indirectly affected by biotic or abiotic stress factors. As a major group of secondary metabolites in plants commonly consumed as food, they are of importance in both the food industry and human nutrition. It is known that arbuscular mycorrhizal (AM) fungi can influence the plant secondary metabolic pathways such as the synthesis of essential oils in aromatic plants, of secondary metabolites in roots, and increase flavonoid concentration. Plant Growth-Promoting Bacteria (PGPB) are able to increase plant growth, improving plant nutrition and supporting plant development under natural or stressed conditions. Various studies confirmed that a number of bacterial species living on and inside the root system are beneficial for plant growth, yield and crop quality. In this work it is shown that inoculation with AM fungi and/or with selected and tested Pseudomonas strains, under conditions of reduced fertilization, increases anthocyanin concentration in the fruits of strawberry.

  14. Arbuscular mycorrhizal fungi and plant growth-promoting pseudomonads increases anthocyanin concentration in strawberry fruits (Fragaria x ananassa var. Selva) in conditions of reduced fertilization.

    PubMed

    Lingua, Guido; Bona, Elisa; Manassero, Paola; Marsano, Francesco; Todeschini, Valeria; Cantamessa, Simone; Copetta, Andrea; D'Agostino, Giovanni; Gamalero, Elisa; Berta, Graziella

    2013-01-01

    Anthocyanins are a group of common phenolic compounds in plants. They are mainly detected in flowers and fruits, are believed to play different important roles such as in the attraction of animals and seed dispersal, and also in the increase of the antioxidant response in tissues directly or indirectly affected by biotic or abiotic stress factors. As a major group of secondary metabolites in plants commonly consumed as food, they are of importance in both the food industry and human nutrition. It is known that arbuscular mycorrhizal (AM) fungi can influence the plant secondary metabolic pathways such as the synthesis of essential oils in aromatic plants, of secondary metabolites in roots, and increase flavonoid concentration. Plant Growth-Promoting Bacteria (PGPB) are able to increase plant growth, improving plant nutrition and supporting plant development under natural or stressed conditions. Various studies confirmed that a number of bacterial species living on and inside the root system are beneficial for plant growth, yield and crop quality. In this work it is shown that inoculation with AM fungi and/or with selected and tested Pseudomonas strains, under conditions of reduced fertilization, increases anthocyanin concentration in the fruits of strawberry. PMID:23924942

  15. Arbuscular Mycorrhizal Fungi and Plant Growth-Promoting Pseudomonads Increases Anthocyanin Concentration in Strawberry Fruits (Fragaria x ananassa var. Selva) in Conditions of Reduced Fertilization

    PubMed Central

    Lingua, Guido; Bona, Elisa; Manassero, Paola; Marsano, Francesco; Todeschini, Valeria; Cantamessa, Simone; Copetta, Andrea; D’Agostino, Giovanni; Gamalero, Elisa; Berta, Graziella

    2013-01-01

    Anthocyanins are a group of common phenolic compounds in plants. They are mainly detected in flowers and fruits, are believed to play different important roles such as in the attraction of animals and seed dispersal, and also in the increase of the antioxidant response in tissues directly or indirectly affected by biotic or abiotic stress factors. As a major group of secondary metabolites in plants commonly consumed as food, they are of importance in both the food industry and human nutrition. It is known that arbuscular mycorrhizal (AM) fungi can influence the plant secondary metabolic pathways such as the synthesis of essential oils in aromatic plants, of secondary metabolites in roots, and increase flavonoid concentration. Plant Growth-Promoting Bacteria (PGPB) are able to increase plant growth, improving plant nutrition and supporting plant development under natural or stressed conditions. Various studies confirmed that a number of bacterial species living on and inside the root system are beneficial for plant growth, yield and crop quality. In this work it is shown that inoculation with AM fungi and/or with selected and tested Pseudomonas strains, under conditions of reduced fertilization, increases anthocyanin concentration in the fruits of strawberry. PMID:23924942

  16. Involvement of Salicylic Acid on Antioxidant and Anticancer Properties, Anthocyanin Production and Chalcone Synthase Activity in Ginger (Zingiber officinale Roscoe) Varieties

    PubMed Central

    Ghasemzadeh, Ali; Jaafar, Hawa Z. E.; Karimi, Ehsan

    2012-01-01

    The effect of foliar application of salicylic acid (SA) at different concentrations (10−3 M and 10−5 M) was investigated on the production of secondary metabolites (flavonoids), chalcone synthase (CHS) activity, antioxidant activity and anticancer activity (against breast cancer cell lines MCF-7 and MDA-MB-231) in two varieties of Malaysian ginger, namely Halia Bentong and Halia Bara. The results of high performance liquid chromatography (HPLC) analysis showed that application of SA induced the synthesis of anthocyanin and fisetin in both varieties. Anthocyanin and fisetin were not detected in the control plants. Accordingly, the concentrations of some flavonoids (rutin and apigenin) decreased significantly in plants treated with different concentrations of SA. The present study showed that SA enhanced the chalcone synthase (CHS) enzyme activity (involving flavonoid synthesis) and recorded the highest activity value of 5.77 nkat /mg protein in Halia Bara with the 10−5 M SA treatment. As the SA concentration was decreased from 10−3 M to 10−5 M, the free radical scavenging power (FRAP) increased about 23% in Halia Bentong and 10.6% in Halia Bara. At a concentration of 350 μg mL−1, the DPPH antioxidant activity recorded the highest value of 58.30%–72.90% with the 10−5 M SA treatment followed by the 10−3 M SA (52.14%–63.66%) treatment. The lowest value was recorded in the untreated control plants (42.5%–46.7%). These results indicate that SA can act not only as an inducer but also as an inhibitor of secondary metabolites. Meanwhile, the highest anticancer activity against MCF-7 and MDA-MB-231 cell lines was observed for H. Bara extracts treated with 10−5 M SA with values of 61.53 and 59.88%, respectively. The results suggest that the high anticancer activity in these varieties may be related to the high concentration of potent anticancer components including fisetin and anthocyanin. The results thus indicate that the synthesis of flavonoids in

  17. Involvement of salicylic acid on antioxidant and anticancer properties, anthocyanin production and chalcone synthase activity in ginger (Zingiber officinale Roscoe) varieties.

    PubMed

    Ghasemzadeh, Ali; Jaafar, Hawa Z E; Karimi, Ehsan

    2012-01-01

    The effect of foliar application of salicylic acid (SA) at different concentrations (10-3 M and 10-5 M) was investigated on the production of secondary metabolites (flavonoids), chalcone synthase (CHS) activity, antioxidant activity and anticancer activity (against breast cancer cell lines MCF-7 and MDA-MB-231) in two varieties of Malaysian ginger, namely Halia Bentong and Halia Bara. The results of high performance liquid chromatography (HPLC) analysis showed that application of SA induced the synthesis of anthocyanin and fisetin in both varieties. Anthocyanin and fisetin were not detected in the control plants. Accordingly, the concentrations of some flavonoids (rutin and apigenin) decreased significantly in plants treated with different concentrations of SA. The present study showed that SA enhanced the chalcone synthase (CHS) enzyme activity (involving flavonoid synthesis) and recorded the highest activity value of 5.77 nkat /mg protein in Halia Bara with the 10-5 M SA treatment. As the SA concentration was decreased from 10-3 M to 10-5 M, the free radical scavenging power (FRAP) increased about 23% in Halia Bentong and 10.6% in Halia Bara. At a concentration of 350 μg mL-1, the DPPH antioxidant activity recorded the highest value of 58.30%-72.90% with the 10-5 M SA treatment followed by the 10-3 M SA (52.14%-63.66%) treatment. The lowest value was recorded in the untreated control plants (42.5%-46.7%). These results indicate that SA can act not only as an inducer but also as an inhibitor of secondary metabolites. Meanwhile, the highest anticancer activity against MCF-7 and MDA-MB-231 cell lines was observed for H. Bara extracts treated with 10-5 M SA with values of 61.53 and 59.88%, respectively. The results suggest that the high anticancer activity in these varieties may be related to the high concentration of potent anticancer components including fisetin and anthocyanin. The results thus indicate that the synthesis of flavonoids in ginger can be increased

  18. Identification of a R2R3-MYB gene regulating anthocyanin biosynthesis and relationships between its variation and flower color difference in lotus (Nelumbo Adans.).

    PubMed

    Sun, Shan-Shan; Gugger, Paul F; Wang, Qing-Feng; Chen, Jin-Ming

    2016-01-01

    The lotus (Nelumbonaceae: Nelumbo Adans.) is a highly desired ornamental plant, comprising only two extant species, the sacred lotus (N. nucifera Gaerten.) with red flowers and the American lotus (N. lutea Willd.) with yellow flowers. Flower color is the most obvious difference of two species. To better understand the mechanism of flower color differentiation, the content of anthocyanins and the expression levels of four key structural genes (e.g., DFR, ANS, UFGT and GST) were analyzed in two species. Our results revealed that anthocyanins were detected in red flowers, not yellow flowers. Expression analysis showed that no transcripts of GST gene and low expression level of three UFGT genes were detected in yellow flowers. In addition, three regulatory genes (NnMYB5, NnbHLH1 and NnTTG1) were isolated from red flowers and showed a high similarity to corresponding regulatory genes of other species. Sequence analysis of MYB5, bHLH1 and TTG1 in two species revealed striking differences in coding region and promoter region of MYB5 gene. Population analysis identified three MYB5 variants in Nelumbo: a functional allele existed in red flowers and two inactive forms existed in yellow flowers. This result revealed that there was an association between allelic variation in MYB5 gene and flower color difference. Yeast two-hybrid experiments showed that NnMYB5 interacts with NnbHLH1, NlbHLH1 and NnTTG1, and NnTTG1 also interacts with NnbHLH1 and NlbHLH1. The over-expression of NnMYB5 led to anthocyanin accumulation in immature seeds and flower stalks and up-regulation of expression of TT19 in Arabidopsis. Therefore, NnMYB5 is a transcription activator of anthocyanin synthesis. This study helps to elucidate the function of NnMYB5 and will contribute to clarify the mechanism of flower coloration and genetic engineering of flower color in lotus.

  19. Identification of a R2R3-MYB gene regulating anthocyanin biosynthesis and relationships between its variation and flower color difference in lotus (Nelumbo Adans.)

    PubMed Central

    Sun, Shan-Shan

    2016-01-01

    The lotus (Nelumbonaceae: Nelumbo Adans.) is a highly desired ornamental plant, comprising only two extant species, the sacred lotus (N. nucifera Gaerten.) with red flowers and the American lotus (N. lutea Willd.) with yellow flowers. Flower color is the most obvious difference of two species. To better understand the mechanism of flower color differentiation, the content of anthocyanins and the expression levels of four key structural genes (e.g., DFR, ANS, UFGT and GST) were analyzed in two species. Our results revealed that anthocyanins were detected in red flowers, not yellow flowers. Expression analysis showed that no transcripts of GST gene and low expression level of three UFGT genes were detected in yellow flowers. In addition, three regulatory genes (NnMYB5, NnbHLH1 and NnTTG1) were isolated from red flowers and showed a high similarity to corresponding regulatory genes of other species. Sequence analysis of MYB5, bHLH1 and TTG1 in two species revealed striking differences in coding region and promoter region of MYB5 gene. Population analysis identified three MYB5 variants in Nelumbo: a functional allele existed in red flowers and two inactive forms existed in yellow flowers. This result revealed that there was an association between allelic variation in MYB5 gene and flower color difference. Yeast two-hybrid experiments showed that NnMYB5 interacts with NnbHLH1, NlbHLH1 and NnTTG1, and NnTTG1 also interacts with NnbHLH1 and NlbHLH1. The over-expression of NnMYB5 led to anthocyanin accumulation in immature seeds and flower stalks and up-regulation of expression of TT19 in Arabidopsis. Therefore, NnMYB5 is a transcription activator of anthocyanin synthesis. This study helps to elucidate the function of NnMYB5 and will contribute to clarify the mechanism of flower coloration and genetic engineering of flower color in lotus. PMID:27635336

  20. Identification of a R2R3-MYB gene regulating anthocyanin biosynthesis and relationships between its variation and flower color difference in lotus (Nelumbo Adans.)

    PubMed Central

    Sun, Shan-Shan

    2016-01-01

    The lotus (Nelumbonaceae: Nelumbo Adans.) is a highly desired ornamental plant, comprising only two extant species, the sacred lotus (N. nucifera Gaerten.) with red flowers and the American lotus (N. lutea Willd.) with yellow flowers. Flower color is the most obvious difference of two species. To better understand the mechanism of flower color differentiation, the content of anthocyanins and the expression levels of four key structural genes (e.g., DFR, ANS, UFGT and GST) were analyzed in two species. Our results revealed that anthocyanins were detected in red flowers, not yellow flowers. Expression analysis showed that no transcripts of GST gene and low expression level of three UFGT genes were detected in yellow flowers. In addition, three regulatory genes (NnMYB5, NnbHLH1 and NnTTG1) were isolated from red flowers and showed a high similarity to corresponding regulatory genes of other species. Sequence analysis of MYB5, bHLH1 and TTG1 in two species revealed striking differences in coding region and promoter region of MYB5 gene. Population analysis identified three MYB5 variants in Nelumbo: a functional allele existed in red flowers and two inactive forms existed in yellow flowers. This result revealed that there was an association between allelic variation in MYB5 gene and flower color difference. Yeast two-hybrid experiments showed that NnMYB5 interacts with NnbHLH1, NlbHLH1 and NnTTG1, and NnTTG1 also interacts with NnbHLH1 and NlbHLH1. The over-expression of NnMYB5 led to anthocyanin accumulation in immature seeds and flower stalks and up-regulation of expression of TT19 in Arabidopsis. Therefore, NnMYB5 is a transcription activator of anthocyanin synthesis. This study helps to elucidate the function of NnMYB5 and will contribute to clarify the mechanism of flower coloration and genetic engineering of flower color in lotus.

  1. Identification of a R2R3-MYB gene regulating anthocyanin biosynthesis and relationships between its variation and flower color difference in lotus (Nelumbo Adans.).

    PubMed

    Sun, Shan-Shan; Gugger, Paul F; Wang, Qing-Feng; Chen, Jin-Ming

    2016-01-01

    The lotus (Nelumbonaceae: Nelumbo Adans.) is a highly desired ornamental plant, comprising only two extant species, the sacred lotus (N. nucifera Gaerten.) with red flowers and the American lotus (N. lutea Willd.) with yellow flowers. Flower color is the most obvious difference of two species. To better understand the mechanism of flower color differentiation, the content of anthocyanins and the expression levels of four key structural genes (e.g., DFR, ANS, UFGT and GST) were analyzed in two species. Our results revealed that anthocyanins were detected in red flowers, not yellow flowers. Expression analysis showed that no transcripts of GST gene and low expression level of three UFGT genes were detected in yellow flowers. In addition, three regulatory genes (NnMYB5, NnbHLH1 and NnTTG1) were isolated from red flowers and showed a high similarity to corresponding regulatory genes of other species. Sequence analysis of MYB5, bHLH1 and TTG1 in two species revealed striking differences in coding region and promoter region of MYB5 gene. Population analysis identified three MYB5 variants in Nelumbo: a functional allele existed in red flowers and two inactive forms existed in yellow flowers. This result revealed that there was an association between allelic variation in MYB5 gene and flower color difference. Yeast two-hybrid experiments showed that NnMYB5 interacts with NnbHLH1, NlbHLH1 and NnTTG1, and NnTTG1 also interacts with NnbHLH1 and NlbHLH1. The over-expression of NnMYB5 led to anthocyanin accumulation in immature seeds and flower stalks and up-regulation of expression of TT19 in Arabidopsis. Therefore, NnMYB5 is a transcription activator of anthocyanin synthesis. This study helps to elucidate the function of NnMYB5 and will contribute to clarify the mechanism of flower coloration and genetic engineering of flower color in lotus. PMID:27635336

  2. Repression of protein translation and mTOR signaling by proteasome inhibitor in colon cancer cells

    SciTech Connect

    Wu, William Ka Kei; Volta, Viviana; Cho, Chi Hin; Wu, Ya Chun; Li, Hai Tao; Yu, Le; Li, Zhi Jie; Sung, Joseph Jao Yiu

    2009-09-04

    Protein homeostasis relies on a balance between protein synthesis and protein degradation. The ubiquitin-proteasome system is a major catabolic pathway for protein degradation. In this respect, proteasome inhibition has been used therapeutically for the treatment of cancer. Whether inhibition of protein degradation by proteasome inhibitor can repress protein translation via a negative feedback mechanism, however, is unknown. In this study, proteasome inhibitor MG-132 lowered the proliferation of colon cancer cells HT-29 and SW1116. In this connection, MG-132 reduced the phosphorylation of mammalian target of rapamycin (mTOR) at Ser2448 and Ser2481 and the phosphorylation of its downstream targets 4E-BP1 and p70/p85 S6 kinases. Further analysis revealed that MG-132 inhibited protein translation as evidenced by the reductions of {sup 35}S-methionine incorporation and polysomes/80S ratio. Knockdown of raptor, a structural component of mTOR complex 1, mimicked the anti-proliferative effect of MG-132. To conclude, we demonstrate that the inhibition of protein degradation by proteasome inhibitor represses mTOR signaling and protein translation in colon cancer cells.

  3. Interactions between Escherichia coli RNA polymerase and lambda repressor. Mutations in PRM affect repression of PR.

    PubMed

    Hwang, J J; Gussin, G N

    1988-04-20

    The rightward operator, OR, of bacteriophage lambda is part of a complex regulatory region that includes PRM, the promoter for repressor synthesis by a prophage, the rightward early promoter PR, and three repressor-binding sites, OR1, OR2 and OR3. By binding to OR2, repressor blocks transcription from PR and simultaneously stimulates the formation of open complexes between RNA polymerase and PRM. In this letter, we describe a test of the hypothesis that the interaction between RNA polymerase bound at PRM and repressor bound at OR2 increases the apparent affinity of repressor for OR. One implication of this hypothesis is that the amount of repressor required for repression of PR should be inversely correlated with PRM promoter strength. This is indeed the case. The amount of repressor required for 50% repression of PR is decreased by prmup-1, an "up" mutation of PRM, and is increased by prm- mutations. An unexpected finding is that in addition to their effect on the apparent affinity of repressor for OR, mutations in the -35 region of PRM alter the shape of repressor-titration curves. We propose that these mutations alter the interaction between RNA polymerase bound at PRM and repressor bound at OR2 in such a way that cooperativity in the binding of repressor to OR1 and OR2 is also disrupted.

  4. CHES1/FOXN3 regulates cell proliferation by repressing PIM2 and protein biosynthesis

    PubMed Central

    Huot, Geneviève; Vernier, Mathieu; Bourdeau, Véronique; Doucet, Laurent; Saint-Germain, Emmanuelle; Gaumont-Leclerc, Marie-France; Moro, Alejandro; Ferbeyre, Gerardo

    2014-01-01

    The expression of the forkhead transcription factor checkpoint suppressor 1 (CHES1), also known as FOXN3, is reduced in many types of cancers. We show here that CHES1 decreases protein synthesis and cell proliferation in tumor cell lines but not in normal fibroblasts. Conversely, short hairpin RNA–mediated depletion of CHES1 increases tumor cell proliferation. Growth suppression depends on the CHES1 forkhead DNA-binding domain and correlates with the nuclear localization of CHES1. CHES1 represses the expression of multiple genes, including the kinases PIM2 and DYRK3, which regulate protein biosynthesis, and a number of genes in cilium biogenesis. CHES1 binds directly to the promoter of PIM2, and in cells expressing CHES1 the levels of PIM2 are reduced, as well as the phosphorylation of the PIM2 target 4EBP1. Overexpression of PIM2 or eIF4E partially reverses the antiproliferative effect of CHES1, indicating that PIM2 and protein biosynthesis are important targets of the antiproliferative effect of CHES1. In several human hematopoietic cancers, CHES1 and PIM2 expressions are inversely correlated, suggesting that repression of PIM2 by CHES1 is clinically relevant. PMID:24403608

  5. Epigenetic repression of ribosomal RNA transcription by ROCK-dependent aberrant cytoskeletal organization

    PubMed Central

    Wu, Tse-Hsiang; Kuo, Yuan-Yeh; Lee, Hsiao-Hui; Kuo, Jean-Cheng; Ou, Meng-Hsin; Chang, Zee-Fen

    2016-01-01

    It is known that ribosomal RNA (rRNA) synthesis is regulated by cellular energy and proliferation status. In this study, we investigated rRNA gene transcription in response to cytoskeletal stress. Our data revealed that the cell shape constrained by isotropic but not elongated micropatterns in HeLa cells led to a significant reduction in rRNA transcription dependent on ROCK. Expression of a dominant-active form of ROCK also repressed rRNA transcription. Isotropic constraint and ROCK over-activation led to different types of aberrant F-actin organization, but their suppression effects on rRNA transcription were similarly reversed by inhibition of histone deacetylase (HDAC) or overexpression of a dominant negative form of Nesprin, which shields the signal transmitted from actin filament to the nuclear interior. We further showed that the binding of HDAC1 to the active fraction of rDNA genes is increased by ROCK over-activation, thus reducing H3K9/14 acetylation and suppressing transcription. Our results demonstrate an epigenetic control of active rDNA genes that represses rRNA transcription in response to the cytoskeletal stress. PMID:27350000

  6. CHES1/FOXN3 regulates cell proliferation by repressing PIM2 and protein biosynthesis.

    PubMed

    Huot, Geneviève; Vernier, Mathieu; Bourdeau, Véronique; Doucet, Laurent; Saint-Germain, Emmanuelle; Gaumont-Leclerc, Marie-France; Moro, Alejandro; Ferbeyre, Gerardo

    2014-03-01

    The expression of the forkhead transcription factor checkpoint suppressor 1 (CHES1), also known as FOXN3, is reduced in many types of cancers. We show here that CHES1 decreases protein synthesis and cell proliferation in tumor cell lines but not in normal fibroblasts. Conversely, short hairpin RNA-mediated depletion of CHES1 increases tumor cell proliferation. Growth suppression depends on the CHES1 forkhead DNA-binding domain and correlates with the nuclear localization of CHES1. CHES1 represses the expression of multiple genes, including the kinases PIM2 and DYRK3, which regulate protein biosynthesis, and a number of genes in cilium biogenesis. CHES1 binds directly to the promoter of PIM2, and in cells expressing CHES1 the levels of PIM2 are reduced, as well as the phosphorylation of the PIM2 target 4EBP1. Overexpression of PIM2 or eIF4E partially reverses the antiproliferative effect of CHES1, indicating that PIM2 and protein biosynthesis are important targets of the antiproliferative effect of CHES1. In several human hematopoietic cancers, CHES1 and PIM2 expressions are inversely correlated, suggesting that repression of PIM2 by CHES1 is clinically relevant. PMID:24403608

  7. Coordinate Transcriptional and Translational Repression of p53 by TGFβ1 Impairs the Stress Response

    PubMed Central

    López-Díaz, Fernando J.; Gascard, Philippe; Balakrishnan, Sri Kripa; Zhao, Jianxin; del Rincon, Sonia V.; Spruck, Charles; Tlsty, Thea D.; Emerson, Beverly M.

    2013-01-01

    Summary Cellular stress results in profound changes in RNA and protein synthesis. How cells integrate this intrinsic, p53-centered program with extracellular signals is largely unknown. We demonstrate that TGFβ1 signaling interferes with the stress response through coordinate transcriptional and translational repression of p53 levels, which reduces p53-activated transcription, and apoptosis in precancerous cells. Mechanistically, E2F4 binds constitutively to the TP53 gene and induces transcription. TGFβ1-activated Smads are recruited to a composite Smad/E2F4 element by an E2F4/p107 complex that switches to a Smad co-repressor, which represses TP53 transcription. TGFβ1 also causes dissociation of ribosomal protein RPL26 and elongation factor eEF1A from p53 mRNA, thereby reducing p53 mRNA association with polyribosomes and p53 translation. TGFβ1-signalling is dominant over stress-induced transcription and translation of p53 and prevents stress-imposed downregulation of Smad proteins. Thus, crosstalk between the TGFβ and p53 pathways defines a major node of regulation in the cellular stress response, enhancing drug resistance. PMID:23706820

  8. Cranberry anthocyanin extract prolongs lifespan of fruit flies.

    PubMed

    Wang, Lijun; Li, Yuk Man; Lei, Lin; Liu, Yuwei; Wang, Xiaobo; Ma, Ka Ying; Chen, Zhen-Yu

    2015-09-01

    Cranberry is an excellent source of dietary antioxidants. The present study investigated the effect of cranberry anthocyanin (CrA) extract on the lifespan of fruit flies with focus on its interaction with aging-related genes including superoxide dismutase (SOD), catalase (CAT), methuselah (MTH), insulin receptor (InR), target of rapamycin (TOR), hemipterus (Hep), and phosphoenolpyruvate carboxykinase (PEPCK). Results showed that diet containing 20mg/mL CrA could significantly prolong the mean lifespan of fruit flies by 10% compared with the control diet. This was accompanied by up-regulation of SOD1 and down-regulation of MTH, InR, TOR and PEPCK. The stress resistance test demonstrated that CrA could reduce the mortality rate induced by H2O2 but not by paraquat. It was therefore concluded that the lifespan-prolonging activity of CrA was most likely mediated by modulating the genes of SOD1, MTH, InR, TOR and PEPCK. PMID:26159161

  9. Stability of anthocyanins in frozen and freeze-dried raspberries during long-term storage: in relation to glass transition.

    PubMed

    Syamaladevi, Roopesh M; Sablani, Shyam S; Tang, Juming; Powers, Joseph; Swanson, Barry G

    2011-08-01

    Anthocyanins, natural plant pigments in the flavonoid group, are responsible for the red color and some of the nutraceutical benefits of raspberries. This study explores anthocyanin degradation in frozen and freeze-dried raspberries during storage in relation to glass transition temperatures. Frozen raspberries were stored at -80, -35, and -20 °C, while freeze-dried raspberries were stored at selected water activity (a(w)) values ranging from 0.05 to 0.75 at room temperature (23 °C) for more than a year. The characteristic glass transition temperatures (T'(g)) of raspberries with high water content and glass transition temperature (T(g)) of raspberries with small water content were determined using a differential scanning calorimeter. The pH differential method was used to determine the quantity of anthocyanins in frozen and freeze-dried raspberries at selected time intervals. The total anthocyanins in raspberries fluctuated during 378 d of storage at -20 and -35, and -80 °C. Anthocyanin degradation in freeze-dried raspberries ranged from 27% to 32% and 78% to 89% at a(w) values of 0.05 to 0.07 and 0.11 to 0.43, respectively, after 1 y. Anthocyanins were not detectable in freeze-dried raspberries stored at a(w) values of 0.53 to 0.75 after 270 d. First order and Weibull equations were used to fit the anthocyanin degradation in freeze-dried raspberries. The 1(st)-order rate constant (k) of anthocyanin degradation ranged from 0.003 to 0.023 days⁻¹ at the selected water activities. Significant anthocyanin degradation occurred in both the glassy and rubbery states of freeze-dried raspberries during long-term storage. However, the rate of anthocyanin degradation in freeze-dried raspberries stored in the glassy state was significantly smaller than the rate of anthocyanin degradation in the rubbery state. PMID:22417493

  10. Heterologous expression of IbMYB1a by different promoters exhibits different patterns of anthocyanin accumulation in tobacco.

    PubMed

    An, Chul Han; Lee, Ki-Won; Lee, Sang-Hoon; Jeong, Yu Jeong; Woo, Su Gyoung; Chun, Hyokon; Park, Youn-Il; Kwak, Sang-Soo; Kim, Cha Young

    2015-04-01

    We previously reported that the transient and stable expression of IbMYB1a produced anthocyanin pigmentation in tobacco leaves and transgenic Arabidopsis plants, respectively. To further determine the effects of different promoters on the expression of IbMYB1a and anthocyanin production, we generated and characterized stably transformed tobacco (Nicotiana tabacum SR1) plants expressing IbMYB1a under the control of three different promoters. We compared the differences in anthocyanin accumulation patterns and phenotypic features of the leaves of these transgenic tobacco plants during growth. Expression of IbMYB1a under the control of these three different promoters led to a remarkable variation in anthocyanin pigmentation in tobacco leaves. The anthocyanin contents of the leaves of the SPO-IbMYB1a-OX (SPO-M) line were higher than those of the SWPA2-IbMYB1a-OX (SPA-M) and 35S-IbMYB1a-OX (35S-M) lines. High levels of anthocyanin pigments negatively affected plant growth in the SPO-M lines, resulting delayed growth and, occasionally, a stunted phenotype. Furthermore, HPLC analysis revealed that transcriptional regulation of IbMYB1a led to the production of cyanidin-based anthocyanins in the tobacco plants. In addition, RT-PCR analysis revealed that IbMYB1a expression induced the up-regulation of several structural genes in the anthocyanin biosynthetic pathway, including DFR and ANS. Differential expression levels of IbMYB1a under the control of different promoters were highly correlated with the expression levels of the structural genes, thereby affecting anthocyanin production levels. These results indicate that IbMYB1a positively controls the expression of multiple anthocyanin biosynthetic genes and anthocyanin accumulation in heterologous tobacco plants. PMID:25681576

  11. CRISPR Technology for Genome Activation and Repression in Mammalian Cells.

    PubMed

    Du, Dan; Qi, Lei S

    2016-01-01

    Targeted modulation of transcription is necessary for understanding complex gene networks and has great potential for medical and industrial applications. CRISPR is emerging as a powerful system for targeted genome activation and repression, in addition to its use in genome editing. This protocol describes how to design, construct, and experimentally validate the function of sequence-specific single guide RNAs (sgRNAs) for sequence-specific repression (CRISPRi) or activation (CRISPRa) of transcription in mammalian cells. In this technology, the CRISPR-associated protein Cas9 is catalytically deactivated (dCas9) to provide a general platform for RNA-guided DNA targeting of any locus in the genome. Fusion of dCas9 to effector domains with distinct regulatory functions enables stable and efficient transcriptional repression or activation in mammalian cells. Delivery of multiple sgRNAs further enables activation or repression of multiple genes. By using scaffold RNAs (scRNAs), different effectors can be recruited to different genes for simultaneous activation of some and repression of others. The CRISPRi and CRISPRa methods provide powerful tools for sequence-specific control of gene expression on a genome-wide scale to aid understanding gene functions and for engineering genetic regulatory systems. PMID:26729910

  12. Mechanism of promoter repression by Lac repressor-DNA loops.

    PubMed

    Becker, Nicole A; Peters, Justin P; Maher, L James; Lionberger, Troy A

    2013-01-01

    The Escherichia coli lactose (lac) operon encodes the first genetic switch to be discovered, and lac remains a paradigm for studying negative and positive control of gene expression. Negative control is believed to involve competition of RNA polymerase and Lac repressor for overlapping binding sites. Contributions to the local Lac repressor concentration come from free repressor and repressor delivered to the operator from remote auxiliary operators by DNA looping. Long-standing questions persist concerning the actual role of DNA looping in the mechanism of promoter repression. Here, we use experiments in living bacteria to resolve four of these questions. We show that the distance dependence of repression enhancement is comparable for upstream and downstream auxiliary operators, confirming the hypothesis that repressor concentration increase is the principal mechanism of repression loops. We find that as few as four turns of DNA can be constrained in a stable loop by Lac repressor. We show that RNA polymerase is not trapped at repressed promoters. Finally, we show that constraining a promoter in a tight DNA loop is sufficient for repression even when promoter and operator do not overlap. PMID:23143103

  13. Salt stress represses production of extracellular proteases in Bacillus pumilus.

    PubMed

    Liu, R F; Huang, C L; Feng, H

    2015-05-11

    Bacillus pumilus is able to secrete subtilisin-like prote-ases, one of which has been purified and characterized biochemically, demonstrating great potential for use in industrial applications. In the current study, the biosynthesis and transcription of extracellular pro-teases in B. pumilus (BA06) under salt stress were investigated using various methods, including a proteolytic assay, zymogram analysis, and real-time PCR. Our results showed that total extracellular proteolytic activity, both in fermentation broth and on milk-containing agar plates, was considerably repressed by salt in a dosage-dependent manner. As Bacillus species usually secret multiple extracellular proteases, a vari-ety of individual extracellular protease encoding genes were selected for real-time PCR analysis. It was shown that proteases encoded by the aprE and aprX genes were the major proteases in the fermentation broth in terms of their transcripts in B. pumilus. Further, transcription of aprE, aprX, and epr genes was indeed repressed by salt stress. In con-trast, transcription of other genes (e.g., vpr and wprA) was not repressed or significantly affected by the salt. Conclusively, salt stress represses total extracellular proteolytic activity in B. pumilus, which can largely be ascribed to suppression of the major protease-encoding genes (aprE, aprX) at the transcriptional level. In contrast, transcription of other pro-tease-encoding genes (e.g., vpr, wprA) was not repressed by salt stress.

  14. CRISPR Technology for Genome Activation and Repression in Mammalian Cells.

    PubMed

    Du, Dan; Qi, Lei S

    2016-01-04

    Targeted modulation of transcription is necessary for understanding complex gene networks and has great potential for medical and industrial applications. CRISPR is emerging as a powerful system for targeted genome activation and repression, in addition to its use in genome editing. This protocol describes how to design, construct, and experimentally validate the function of sequence-specific single guide RNAs (sgRNAs) for sequence-specific repression (CRISPRi) or activation (CRISPRa) of transcription in mammalian cells. In this technology, the CRISPR-associated protein Cas9 is catalytically deactivated (dCas9) to provide a general platform for RNA-guided DNA targeting of any locus in the genome. Fusion of dCas9 to effector domains with distinct regulatory functions enables stable and efficient transcriptional repression or activation in mammalian cells. Delivery of multiple sgRNAs further enables activation or repression of multiple genes. By using scaffold RNAs (scRNAs), different effectors can be recruited to different genes for simultaneous activation of some and repression of others. The CRISPRi and CRISPRa methods provide powerful tools for sequence-specific control of gene expression on a genome-wide scale to aid understanding gene functions and for engineering genetic regulatory systems.

  15. The effects of anthocyanin-rich wheat diet on the oxidative status and behavior of rats

    PubMed Central

    Janšáková, Katarína; Bábíčková, Janka; Havrlentová, Michaela; Hodosy, Július; Kraic, Ján; Celec, Peter; Tóthová, Ľubomíra

    2016-01-01

    Aim To evaluate the effect of food containing anthocyanin-rich wheat on oxidative status and behavior of healthy rats. Methods Twenty male rats were divided into the control and anthocyanin group. Oral glucose tolerance test was performed, and proteinuria and creatinine clearance were measured. Behavioral analysis was performed in Phenotyper cages. Serum and tissues were collected to measure the markers of oxidative stress and antioxidant status. Results Anthocyanins significantly increased total antioxidant capacity in serum (P = 0.039), decreased advanced oxidation protein products in the kidney (P = 0.002), but increased thiobarbituric acid reactive substances in the kidney compared to the control group. No significant difference between the groups was found in the markers of oxidative stress in the liver and colon, as well as in renal functions and glucose metabolism. The anthocyanin group spent significantly less time in the spotlight zone of the Phenotyper cages (P = 0.040), indicating higher anxiety-like behavior. Conclusion Food containing anthocyanin-rich wheat had positive effects on serum antioxidant status and kidney protein oxidation, but increased lipid peroxidation in the kidney and modified animal behavior related to anxiety. The molecular mechanisms leading to observed effects should be further elucidated. PMID:27106354

  16. Molecular characterization and expression analyses of an anthocyanin synthase gene from Magnolia sprengeri Pamp.

    PubMed

    Shi, Shou-Guo; Li, Shan-Ju; Kang, Yong-Xiang; Liu, Jian-Jun

    2015-01-01

    Anthocyanin synthase (ANS), which catalyzes the conversion of colorless leucoanthocyanins into colored anthocyanins, is a key enzyme in the anthocyanin biosynthetic pathway. It plays important roles in plant development and defense. An ANS gene designated as MsANS was cloned from Magnolia sprengeri using rapid amplification of complementary DNA (cDNA) ends technology. The full-length MsANS is 1171-bp long and contains a 1080-bp open reading frame encoding a 360 amino acid polypeptide. In a sequence alignment analysis, the deduced MsANS protein showed high identity to ANS proteins from other plants: Prunus salicina var. cordata (74 % identity), Ampelopsis grossedentata (74 % identity), Pyrus communis (73 % identity), and Prunus avium (73 % identity). A structural analysis showed that MsANS belongs to 2-oxoglutarate (2OG)- and ferrous iron-dependent oxygenase family because it contains three binding sites for 2OG. Real-time quantitative polymerase chain reaction analyses showed that the transcript level of MsANS was 26-fold higher in red petals than in white petals. The accumulation of anthocyanins in petals of white, pink, and red M. sprengeri flowers was analyzed by HPLC. The main anthocyanin was cyanidin-3-o-glucoside chloride, and the red petals contained the highest concentration of this pigment. PMID:25315387

  17. Effects of abiotic stress on biomass and anthocyanin production in cell cultures of Melastoma malabathricum.

    PubMed

    Chan, L K; Koay, S S; Boey, P L; Bhatt, A

    2010-01-01

    Plant cell cultures could be used as an important tool for biochemical production, ranging from natural coloring (pigments) to pharmaceutical products. Anthocyanins are becoming a very important alternative to synthetic dyes because of increased public concern over the safety of artificial food coloring agents. Several factors are responsible for the production of anthocyanin in cell cultures. In the present study, we investigate the effects of different environmental factors, such as light intensity, irradiance (continuous irradiance or continuous darkness), temperature and medium pH on cell biomass yield and anthocyanin production in cultures of Melastoma malabathricum. Moderate light intensity (301 - 600 lux) induced higher accumulation of anthocyanins in the cells. The cultures exposed to 10-d continuous darkness showed the lowest pigment content, while the cultures exposed to 10-d continuous irradiance showed the highest pigment content. The cell cultures incubated at a lower temperature range (20 ± 2 ºC) grew better and had higher pigment content than those grown at 26 ± 2 ºC and 29 ± 2 ºC. Different medium pH did not affect the yield of cell biomass but anthocyanin accumulation was highest at pH 5.25 - 6.25. PMID:21157639

  18. Bioavailability and Biokinetics of Anthocyanins From Red Grape Juice and Red Wine

    PubMed Central

    Bitsch, Roland

    2004-01-01

    In a comparative study, 9 healthy volunteers ingested a single oral dose of 400 mL red grape juice or red wine with dose-adjusted anthocyanin content (283.5 mg or 279.6 mg, resp) in crossover. The content of anthocyanin glucosides was detected in plasma and urinary excretion. Additionally, the plasmatic antioxidant activity was assessed after intake. Based on the plasma content, biokinetic criteria of the single anthocyanins were calculated, such as AUC, cmax, tmax, and the elimination rate t1/2. The urinary excretion of total anthocyanins differed significantly and amounted to 0.18% (red wine) and 0.23% (red grape juice) of the administered dose. Additionally, the plasmatic antioxidant activity increased to higher levels after juice ingestion compared to wine. The intestinal absorption of the anthocyanins of red grape juice seemed to be improved compared to red wine, suggesting a possible synergistic effect of the glucose content of the juice. The improved absorption resulted in an enhanced plasmatic bioactivity. PMID:15577192

  19. Approaches to understanding the contribution of anthocyanins to the antioxidant capacity of pasteurized pomegranate juices.

    PubMed

    Vegara, Salud; Mena, Pedro; Martí, Nuria; Saura, Domingo; Valero, Manuel

    2013-12-01

    Influence of processing and storage conditions on anthocyanin stability and antioxidant activity of clarified and cloudy juices from arils of the 'Mollar' pomegranate variety was studied. Clarification process reduced the content of total monomeric and individual anthocyanins, and increased the antioxidant activity of pomegranate juice. Thermal treatments (65 and 90 °C for 30 or 5 s) decreased the percentage of polymeric anthocyanin form, increasing on the contrary the monomeric one. In any case, storage temperature was the main factor affecting all the parameters tested. Cyanidin 3-O-glucoside (Cy3G) was more instable than delphinidin 3,5-di (Dp3,5dG) and cyaniding 3,5-diglucosides (Cy3,5dG). A linear relationship was observed between oxygen radical absorbance capacity (ORAC) and total monomeric anthocyanins, suggesting that they contributed strongly to the antioxidant capacity. Results presented in this study show that hurdle technology (heating plus refrigeration) may help to reduce anthocyanin degradation in pasteurized pomegranate juice, avoiding a dramatic impact on its colour and preserving the beneficial effects of this specific bioactive compounds on human health. PMID:23870870

  20. Effects of cold atmospheric gas phase plasma on anthocyanins and color in pomegranate juice.

    PubMed

    Bursać Kovačević, Danijela; Putnik, Predrag; Dragović-Uzelac, Verica; Pedisić, Sandra; Režek Jambrak, Anet; Herceg, Zoran

    2016-01-01

    The aim of the study was to evaluate effects of cold atmospheric gas phase plasma on anthocyanins and color in pomegranate juice. Outcomes of plasma treatment were observed at different operating conditions: (i) treatment time (3, 5, 7 min), (ii) treated juice volume (3, 4, 5 cm(3)), and (iii) gas flow (0.75, 1, 1.25 dm(3)/min). The greatest anthocyanin stability was found at: 3 min treatment time, 5 cm(3) sample volume, and 0.75 dm(3)/min gas flow. Plasma treatment yielded higher anthocyanin content from 21% to 35%. Multivariate analysis showed that total color change was not associated with sample volume and treatment time, however it declined with increased gas flow. The change of color increased in comparison treated vs. untreated pomegranate juice. Constructed mathematical equation confirmed that increase of anthocyanin content increased with gas flow, sample volume and change in color. In summary, this study showed that plasma treatment had positive influences on anthocyanins stability and color change in cloudy pomegranate juice.

  1. Antioxidant capacity and anthocyanin profile of sour cherry (Prunus cerasus L.) juice.

    PubMed

    Damar, Irem; Ekşi, Aziz

    2012-12-15

    The antioxidant capacities, total polyphenolic content and monomeric anthocyanin content of eleven types of sour cherry juice obtained from different varieties of sour cherries were investigated. Antioxidant capacity, total polyphenolic content and monomeric anthocyanin contents of the juices were within the ranges 20.0-37.9 mmol/L, 1510-2550 and 350.0-633.5mg/L, respectively. The main anthocyanin compound in sour cherry juice was cyanidin-3-glucosylrutinoside at concentrations between 140.3 and 320.9 mg/L. Cyanidin-3-glucosylrutinoside was followed by cyanidin-3-rutinoside within a concentration range of 25.5-85.5mg/L. Cyanidin-3-sophoroside and cyanidin-3-glucoside contents were relatively low (2.6-21.5 and 2.0-9.9 mg/L). Anthocyanin capacity and total polyphenol content were fairly well correlated (r=0.742, p<0.01), whereas the correlation between antioxidant capacity and monomeric anthocyanin content was insignificant (r=0.423, p>0.05). The correlation between antioxidant capacity - cya-3-glucosylrutinoside (r=0.606, p<0.01) and antioxidant capacity - cya-3-rutinoside (r=0.628, p<0.01) was significant. PMID:22980889

  2. Free radical scavenging activity and anthocyanin profile of Cabernet Sauvignon wines from the Balkan region.

    PubMed

    Radovanović, Blaga; Radovanović, Aleksandra

    2010-06-10

    The present study is focused on anthocyanin derivatives characterizing the antioxidant activity of Cabernet Sauvignon wines produced from different vineyard regions in the Balkans. These bioactive compounds were quantified with a high performance liquid chromatography (HPLC)-diode array detection (DAD) method. The antiradical activity was estimated by the ability of the wine to scavenge the stable 2,2;-diphenyl-1-picrylhydrazyl free radical (DPPH(*)). The results show that the total anthocyanin content varied from 205.88 to 1940.28 mg/L, depending on agroclimatic factors and the enological practices of the corresponding vineyard region. The most prominent antocyanin in all investigated Cabernet Sauvignon wines was malvidin-3-O-monoglucoside, which accounted for 50.57% of total content, followed by its acetyl derivatives, 15.45%, and p-coumaryl derivatives 5.66%. The relationship between the anthocyanin derivatives and free radical scavenging activity is discussed. A high correlation between total anthocyanin content and DPPH scavenging ability of tested wines was confirmed (r(2) = 0.9619). The significant correlations were obtained between antiradical activity and the sum of 3-monoglucoside (r(2) = 0.95594), the sum of 3-acetyl-3-glucoside (r(2) = 0.9728) and the sum of p-coumaryl-3-glucoside (r(2) = 0.8873) of wine samples. It can be concluded that, the anthocyanin composition can be used as biochemical marker for the authenticity of red grape cultivar and their corresponding single-cultivar wine.

  3. Contents of anthocyanins and ellagitannins in selected foods consumed in Finland.

    PubMed

    Koponen, Jani M; Happonen, Anu M; Mattila, Pirjo H; Törrönen, A Riitta

    2007-02-21

    Numerous in vitro and in vivo studies have suggested that dietary anthocyanins and ellagitannins or ellagic acid might have beneficial health effects. Epidemiological evidence on the disease-preventing potential of these polyphenols is lacking, due to the absence of reliable data on their contents in foods. In this study was analyzed the content of anthocyanins and ellagitannins (as ellagic acid equivalents after acid hydrolysis) in foods consumed in Finland, including berries, fruits, vegetables, and processed products, using high-performance liquid chromatographic (HPLC) methods. Anthocyanins were detected in 41 of 54 selected food items. The total anthocyanin content varied in berries from 1 to 611 mg/100 g, in fruits from 2 to 66 mg/100 g, and in vegetables from 3 to 75 mg/100 g of fresh weight as the weight of the aglycone. Ellagitannins were screened in 33 food items, but were detected only in 5 species of berries, that is, in cloudberry, raspberry, rose hip, strawberry, and sea buckthorn, the content ranging from 1 to 330 mg/100 g. The results underscore the superiority of berries, especially dark blue or red berries, as excellent sources of anthocyanins and certain berries of the Rosaceae family as the major source of ellagitannins in the Finnish diet. PMID:17261015

  4. Bioavailability of anthocyanins and colonic polyphenol metabolites following consumption of aronia berry extract.

    PubMed

    Xie, Liyang; Lee, Sang Gil; Vance, Terrence M; Wang, Ying; Kim, Bohkyung; Lee, Ji-Young; Chun, Ock K; Bolling, Bradley W

    2016-11-15

    A single-dose pharmacokinetic trial was conducted in 6 adults to evaluate the bioavailability of anthocyanins and colonic polyphenol metabolites after consumption of 500mg aronia berry extract. UHPLC-MS methods were developed to quantitate aronia berry polyphenols and their metabolites in plasma and urine. While anthocyanins were bioavailable, microbial phenolic catabolites increased ∼10-fold more than anthocyanins in plasma and urine. Among the anthocyanins, cyanidin-3-O-galactoside was rapidly metabolized to peonidin-3-O-galactoside. Aronia polyphenols were absorbed and extensively metabolized with tmax of anthocyanins and other polyphenol catabolites from 1.0h to 6.33h in plasma and urine. Despite significant inter-individual variation in pharmacokinetic parameters, concentrations of polyphenol metabolites in plasma and urine at 24h were positively correlated with total AUC in plasma and urine (r=0.93, and r=0.98, respectively). This suggests that fasting blood and urine collections could be used to estimate polyphenol bioavailability and metabolism after aronia polyphenol consumption.

  5. The immunomodulation effect of Aronia extract lacks association with its antioxidant anthocyanins.

    PubMed

    Xu, Jin; Mojsoska, Biljana

    2013-04-01

    Polyphenols comprise a diverse group of molecules with antioxidative and anti-inflammatory activities. To compare the antioxidative and anti-inflammatory capacity of Aronia melanocarpa berries (chokeberries), recognized for their high content of anthocyanins, a noncytotoxic isolation method was developed to obtain high-purity anthocyanins in the extract. The antioxidative activity of the extract, the anthocyanin-rich fraction (AF) was determined by 1,1-diphenyl-2-picrylhydrazyl radical and ferric-reducing ability of plasma along with resveratrol as a reference. The immunomodulation properties were assessed in lipopolysaccharide (LPS)-stimulated human monocytes mono mac 6. The isolated AF, containing six different anthocyanins, exhibited a stronger antioxidative capacity compared to resveratrol. Resveratrol enhanced tumor necrosis factor-α and reduced interleukin-10 (IL-10) production by LPS, whereas AF only had a slight effect in reducing IL-10. These results demonstrated that there was no major relationship between the antioxidative effect and immunomodulation capacities of AF and resveratrol. The immunomodulatory activity of the extract is associated with bioactive compounds in Aronia other than its anthocyanins.

  6. Sugar Maple Pigments Through the Fall and the Role of Anthocyanin as an Analytical Tool

    NASA Astrophysics Data System (ADS)

    Lindgren, E.; Rock, B.; Middleton, E.; Aber, J.

    2008-12-01

    Sugar maple habitat is projected to almost disappear in future climate scenarios. In fact, many institutions state that these trees are already in decline. Being able to detect sugar maple health could prove to be a useful analytical tool to monitor changes in phenology. Anthocyanin, a red pigment found in sugar maples, is thought to be a universal indicator of plant stress. It is very prominent in the spring during the first flush of leaves, as well as in the fall as leaves senesce. Determining an anthocyanin index that could be used with satellite systems will provide a greater understanding of tree phenology and the distribution of plant stress, both over large areas as well as changes over time. The utilization of anthocyanin for one of it's functions, prevention of oxidative stress, may fluctuate in response to changing climatic conditions that occur during senescence or vary from year to year. By monitoring changes in pigment levels and antioxidant capacity through the fall, one may be able to draw conclusions about the ability to detect anthocyanin remotely from space-based systems, and possibly determine a more specific function for anthocyanin during fall senescence. These results could then be applied to track changes in tree stress.

  7. Sour Cherry (Prunus cerasus L) Anthocyanins as Ingredients for Functional Foods.

    PubMed

    Blando, Federica; Gerardi, Carmela; Nicoletti, Isabella

    2004-01-01

    In the recent years many studies on anthocyanins have revealed their strong antioxidant activity and their possible use as chemotherapeutics. The finding that sour cherries (Prunus cerasus L) (also called tart cherries) contain high levels of anthocyanins that possess strong antioxidant and anti-inflammatory properties has attracted much attention to this species. Here we report the preliminary results of the induction of anthocyanin biosynthesis in sour cherry callus cell cultures. The evaluation and characterization of the in vitro produced pigments are compared to those of the anthocyanins found in vivo in fruits of several sour cherry cultivars. Interestingly, the anthocyanin profiles found in whole fruit extracts were similar in all tested genotypes but were different with respect to the callus extract. The evaluation of antioxidant activity, performed by ORAC and TEAC assays, revealed a relatively high antioxidant capacity for the fruit extracts (from 1145 to 2592 $\\mu $ mol TE/100 g FW) and a lower one for the callus extract (688 $\\mu $ mol TE/100 g FW). PMID:15577186

  8. Sour Cherry (Prunus cerasus L) Anthocyanins as Ingredients for Functional Foods

    PubMed Central

    Blando, Federica

    2004-01-01

    In the recent years many studies on anthocyanins have revealed their strong antioxidant activity and their possible use as chemotherapeutics. The finding that sour cherries (Prunus cerasus L) (also called tart cherries) contain high levels of anthocyanins that possess strong antioxidant and anti-inflammatory properties has attracted much attention to this species. Here we report the preliminary results of the induction of anthocyanin biosynthesis in sour cherry callus cell cultures. The evaluation and characterization of the in vitro produced pigments are compared to those of the anthocyanins found in vivo in fruits of several sour cherry cultivars. Interestingly, the anthocyanin profiles found in whole fruit extracts were similar in all tested genotypes but were different with respect to the callus extract. The evaluation of antioxidant activity, performed by ORAC and TEAC assays, revealed a relatively high antioxidant capacity for the fruit extracts (from 1145 to 2592 μmol TE/100 g FW) and a lower one for the callus extract (688 μmol TE/100 g FW). PMID:15577186

  9. Bioavailability of anthocyanins and colonic polyphenol metabolites following consumption of aronia berry extract.

    PubMed

    Xie, Liyang; Lee, Sang Gil; Vance, Terrence M; Wang, Ying; Kim, Bohkyung; Lee, Ji-Young; Chun, Ock K; Bolling, Bradley W

    2016-11-15

    A single-dose pharmacokinetic trial was conducted in 6 adults to evaluate the bioavailability of anthocyanins and colonic polyphenol metabolites after consumption of 500mg aronia berry extract. UHPLC-MS methods were developed to quantitate aronia berry polyphenols and their metabolites in plasma and urine. While anthocyanins were bioavailable, microbial phenolic catabolites increased ∼10-fold more than anthocyanins in plasma and urine. Among the anthocyanins, cyanidin-3-O-galactoside was rapidly metabolized to peonidin-3-O-galactoside. Aronia polyphenols were absorbed and extensively metabolized with tmax of anthocyanins and other polyphenol catabolites from 1.0h to 6.33h in plasma and urine. Despite significant inter-individual variation in pharmacokinetic parameters, concentrations of polyphenol metabolites in plasma and urine at 24h were positively correlated with total AUC in plasma and urine (r=0.93, and r=0.98, respectively). This suggests that fasting blood and urine collections could be used to estimate polyphenol bioavailability and metabolism after aronia polyphenol consumption. PMID:27283706

  10. Optimization conditions for anthocyanin and phenolic content extraction form purple sweet potato using response surface methodology.

    PubMed

    Ahmed, Maruf; Akter, Mst Sorifa; Eun, Jong-Bang

    2011-02-01

    Purple sweet potato flour could be used to enhance the bioactive components such as phenolic compounds and anthocyanin content that might be used as nutraceutical ingredients for formulated foods. Optimization of anthocyanin and phenolic contents of purple sweet potato were investigated using response surface methodology. A face-centered cube design was used to investigate the effects of three independent variables: namely, drying temperature 55-65°C, citric acid concentration 1-3% w/v and soaking time 1-3 min. The optimal conditions for anthocyanin and phenolic contents were 62.91°C, 1.38%, 2.53 min and 60.94°C, 1.04% and 2.24 min, respectively. However, optimal conditions of anthocyanin content were not apparent. The experimental value of anthocyanin content was 19.78 mg/100 g and total phenolic content was 61.55 mg/g. These data showed that the experimental responses were reasonably close to the predicted responses. Therefore, the results showed that treated flours could be used to enhance the antioxidant activities of functional foods.

  11. Anthocyanins degradation during storage of Hibiscus sabdariffa extract and evolution of its degradation products.

    PubMed

    Sinela, André; Rawat, Nadirah; Mertz, Christian; Achir, Nawel; Fulcrand, Hélène; Dornier, Manuel

    2017-01-01

    Degradation parameters of two main anthocyanins from roselle extract (Hibiscus sabdariffa L.) stored at different temperatures (4-37°C) over 60days were determined. Anthocyanins and some of their degradation products were monitored and quantified using HPLC-MS and DAD. Degradation of anthocyanins followed first-order kinetics and reaction rate constants (k values), which were obtained by non-linear regression, showed that the degradation rate of delphinidin 3-O-sambubioside was higher than that of cyanidin 3-O-sambubioside with k values of 9.2·10(-7)s(-1) and 8.4·10(-7)s(-1) at 37°C respectively. The temperature dependence of the rate of anthocyanin degradation was modeled by the Arrhenius equation. Degradation of delphinidin 3-O-sambubioside (Ea=90kJmol(-1)) tended to be significantly more sensitive to an increase in temperature than cyanidin 3-O-sambubioside (Ea=80kJmol(-1)). Degradation of these anthocyanins formed scission products (gallic and protocatechuic acids respectively) and was accompanied by an increase in polymeric color index. PMID:27507471

  12. Approaches to understanding the contribution of anthocyanins to the antioxidant capacity of pasteurized pomegranate juices.

    PubMed

    Vegara, Salud; Mena, Pedro; Martí, Nuria; Saura, Domingo; Valero, Manuel

    2013-12-01

    Influence of processing and storage conditions on anthocyanin stability and antioxidant activity of clarified and cloudy juices from arils of the 'Mollar' pomegranate variety was studied. Clarification process reduced the content of total monomeric and individual anthocyanins, and increased the antioxidant activity of pomegranate juice. Thermal treatments (65 and 90 °C for 30 or 5 s) decreased the percentage of polymeric anthocyanin form, increasing on the contrary the monomeric one. In any case, storage temperature was the main factor affecting all the parameters tested. Cyanidin 3-O-glucoside (Cy3G) was more instable than delphinidin 3,5-di (Dp3,5dG) and cyaniding 3,5-diglucosides (Cy3,5dG). A linear relationship was observed between oxygen radical absorbance capacity (ORAC) and total monomeric anthocyanins, suggesting that they contributed strongly to the antioxidant capacity. Results presented in this study show that hurdle technology (heating plus refrigeration) may help to reduce anthocyanin degradation in pasteurized pomegranate juice, avoiding a dramatic impact on its colour and preserving the beneficial effects of this specific bioactive compounds on human health.

  13. Investigation of optical properties of anthocyanin doped into sol-gel based matrix

    NASA Astrophysics Data System (ADS)

    Hashim, Hasrina; Abdul Aziz, Nik Mohd Azmi Nik; Isnin, Aishah

    2012-06-01

    Anthocyanin dye was extracted from petal of Hibiscus rosasinensis (Bunga Raya) and doped into sol-gel based matrix to investigate an effect of pH change on its optical properties. Sol-gel matrix based on Vinyl triethoxysilene (VTES) as a precursor was prepared through Sol-gel process at pH 7. The sol was doped with 0.1% of Anthocyanin and the same amount of dye was also dissolved in ethanol as a comparative sample. Hydrochloric Acid, HCl and Tetramethylammonium Hydroxide, TMAH were used to change the pH value by adding them at various concentrations into each sample. The emission spectra and chemical structures of the samples were measured by Spectrofluorometer and Fourier Transform Infrared (FTIR) respectively. When excited at 410 nm, two emission peaks at about 492 and 574 nm were observed for Anthocyanin in acidic environment both in ethanol and VTES sol. In base environment however, only Anthocyanin dissolved in ethanol produced emission peak with a single peak at about 539 nm. The sensitivity of Anthocyanin dye toward pH changes in VTES open a possibility to use it as sensing element in which sol-gel based matrix are known to have higher mechanical strength and thermal stability.

  14. Ecophysiological roles of abaxial anthocyanins in a perennial understorey herb from temperate deciduous forests.

    PubMed

    Fernández-Marín, Beatriz; Esteban, Raquel; Míguez, Fátima; Artetxe, Unai; Castañeda, Verónica; Pintó-Marijuan, Marta; Becerril, José María; García-Plazaola, José Ignacio

    2015-01-01

    Accumulation of abaxial anthocyanins is an intriguing leaf trait particularly common among deeply shaded understorey plants of tropical and temperate forests whose ecological significance is still not properly understood. To shed light on it, possible ecophysiological roles of abaxial anthocyanins were tested in the perennial understorey herb of temperate deciduous forests Saxifraga hirsuta, chosen as a model species due to the coexistence of green and anthocyanic leaves and the presence of an easily removable lower anthocyanic epidermis. Anthocyanins accumulated during autumn, which temporally matched the overstorey leaf fall. Patterns of development of abaxial anthocyanins and direct measurements of photochemical efficiency under monochromatic light were not consistent with a photoprotective hypothesis. Enhancement of light capture also seemed unlikely since the back-scattering of red light towards the lower mesophyll was negligible. Seed germination was similar under acyanic and anthocyanic leaves. A relevant consequence of abaxial anthocyanins was the dramatic reduction of light transmission through the leaf. The dark environment generated underneath the Saxifraga canopy was enhanced by the horizontal repositioning of leaves, which occurs in parallel with reddening. This might play a role in biotic interactions by inhibiting vital processes of competitors, which may be of especial importance in spring before the overstorey leaves sprout. PMID:25922298

  15. Ecophysiological roles of abaxial anthocyanins in a perennial understorey herb from temperate deciduous forests.

    PubMed

    Fernández-Marín, Beatriz; Esteban, Raquel; Míguez, Fátima; Artetxe, Unai; Castañeda, Verónica; Pintó-Marijuan, Marta; Becerril, José María; García-Plazaola, José Ignacio

    2015-01-01

    Accumulation of abaxial anthocyanins is an intriguing leaf trait particularly common among deeply shaded understorey plants of tropical and temperate forests whose ecological significance is still not properly understood. To shed light on it, possible ecophysiological roles of abaxial anthocyanins were tested in the perennial understorey herb of temperate deciduous forests Saxifraga hirsuta, chosen as a model species due to the coexistence of green and anthocyanic leaves and the presence of an easily removable lower anthocyanic epidermis. Anthocyanins accumulated during autumn, which temporally matched the overstorey leaf fall. Patterns of development of abaxial anthocyanins and direct measurements of photochemical efficiency under monochromatic light were not consistent with a photoprotective hypothesis. Enhancement of light capture also seemed unlikely since the back-scattering of red light towards the lower mesophyll was negligible. Seed germination was similar under acyanic and anthocyanic leaves. A relevant consequence of abaxial anthocyanins was the dramatic reduction of light transmission through the leaf. The dark environment generated underneath the Saxifraga canopy was enhanced by the horizontal repositioning of leaves, which occurs in parallel with reddening. This might play a role in biotic interactions by inhibiting vital processes of competitors, which may be of especial importance in spring before the overstorey leaves sprout.

  16. Ecophysiological roles of abaxial anthocyanins in a perennial understorey herb from temperate deciduous forests

    PubMed Central

    Fernández-Marín, Beatriz; Esteban, Raquel; Míguez, Fátima; Artetxe, Unai; Castañeda, Verónica; Pintó-Marijuan, Marta; Becerril, José María; García-Plazaola, José Ignacio

    2015-01-01

    Accumulation of abaxial anthocyanins is an intriguing leaf trait particularly common among deeply shaded understorey plants of tropical and temperate forests whose ecological significance is still not properly understood. To shed light on it, possible ecophysiological roles of abaxial anthocyanins were tested in the perennial understorey herb of temperate deciduous forests Saxifraga hirsuta, chosen as a model species due to the coexistence of green and anthocyanic leaves and the presence of an easily removable lower anthocyanic epidermis. Anthocyanins accumulated during autumn, which temporally matched the overstorey leaf fall. Patterns of development of abaxial anthocyanins and direct measurements of photochemical efficiency under monochromatic light were not consistent with a photoprotective hypothesis. Enhancement of light capture also seemed unlikely since the back-scattering of red light towards the lower mesophyll was negligible. Seed germination was similar under acyanic and anthocyanic leaves. A relevant consequence of abaxial anthocyanins was the dramatic reduction of light transmission through the leaf. The dark environment generated underneath the Saxifraga canopy was enhanced by the horizontal repositioning of leaves, which occurs in parallel with reddening. This might play a role in biotic interactions by inhibiting vital processes of competitors, which may be of especial importance in spring before the overstorey leaves sprout. PMID:25922298

  17. Analysis and characterization of anthocyanins and carotenoids in Japanese blue tomato.

    PubMed

    Ooe, Emi; Ogawa, Kenjirou; Horiuchi, Tadashi; Tada, Hiroyuki; Murase, Hiromi; Tsuruma, Kazuhiro; Shimazawa, Masamitsu; Hara, Hideaki

    2016-01-01

    Tomato (Solanum lycopersicum) is rich in anthocyanins, which are polyphenolic pigments. This study aimed to analyze and characterize the anthocyanin composition in cultivated blue tomato in Japan. The extracts of peel, seed, and pulp of tomatoes were purified following which anthocyanins and lycopene contents were analyzed using high-performance liquid chromatography and electrospray ionization mass spectrometry. Eleven types of anthocyanins were identified, including delphinidin, petunidin, and malvidin. Further, the antioxidant activity of anthocyanins was evaluated using 2,2'-azino-bis-(3-ethylbenzthiazoline-6-sulfonic acid) diammonium salt radical quenching assays and electron spin resonance. "Blue tomato" extracts exert antioxidant activity. Thus, we showed that petunidin was present in the "blue tomato" peel while lycopene was present in the peel and pulp. Additionally, the blue tomato peel extract was found to significantly inhibit H2O2-induced cell death in vitro. This is the first study on cell protective effects of Japanese blue tomato extract and petunidin in murine photoreceptor cells. PMID:26443075

  18. Chondrocyte-intrinsic Smad3 represses Runx2-inducible MMP-13 expression to maintain articular cartilage and prevent osteoarthritis

    PubMed Central

    Chen, Carol G.; Thuillier, Daniel; Chin, Emily N.; Alliston, Tamara

    2012-01-01

    Objective To identify mechanisms by which Smad3 maintains articular cartilage and prevents osteoarthritis. Methods A combination of in vivo and in vitro approaches was used to test the hypothesis that Smad3 represses Runx2-inducible gene expression to prevent articular cartilage degeneration. Col2-Cre;Smad3fl/fl mice allowed study of the chondrocyte-intrinsic role of Smad3, independently of its role in the perichondrium or other tissues. Primary Smad3fl/fl articular chondrocytes and ATDC5 chondroprogenitors were employed to evaluate Smad3 and Runx2 regulation of matrix metalloproteinase-13 (MMP-13) mRNA and protein expression. Results Chondrocyte-specific reduction of Smad3 causes progressive articular cartilage degeneration due to imbalanced cartilage matrix synthesis and degradation. In addition to reduced collagen II mRNA expression, Col2-Cre;Smad3fl/fl articular cartilage is severely deficient in collagen II and aggrecan protein, due to excessive MMP-13-mediated proteolysis of these key cartilage matrix constituents. Normally, TGF-β signals through Smad3 to confer a rapid and dynamic repression of Runx2-inducible MMP-13 expression. However, in the absence of Smad3, TGF-β signals through p38 and Runx2 to induce MMP-13 expression. Conclusion This work elucidates a mechanism by which Smad3 mutations in humans and mice cause cartilage degeneration and osteoarthritis. Specifically, Smad3 maintains the balance between cartilage matrix synthesis and degradation by inducing collagen II expression and repressing Runx2-inducible MMP-13 expression. Selective activation of TGF-β signaling through Smad3, rather than p38, may help to restore the balance between matrix synthesis and proteolysis that is lost in osteoarthritis. PMID:22674505

  19. Interactome of two diverse RNA granules links mRNA localization to translational repression in neurons.

    PubMed

    Fritzsche, Renate; Karra, Daniela; Bennett, Keiryn L; Ang, Foong Yee; Heraud-Farlow, Jacki E; Tolino, Marco; Doyle, Michael; Bauer, Karl E; Thomas, Sabine; Planyavsky, Melanie; Arn, Eric; Bakosova, Anetta; Jungwirth, Kerstin; Hörmann, Alexandra; Palfi, Zsofia; Sandholzer, Julia; Schwarz, Martina; Macchi, Paolo; Colinge, Jacques; Superti-Furga, Giulio; Kiebler, Michael A

    2013-12-26

    Transport of RNAs to dendrites occurs in neuronal RNA granules, which allows local synthesis of specific proteins at active synapses on demand, thereby contributing to learning and memory. To gain insight into the machinery controlling dendritic mRNA localization and translation, we established a stringent protocol to biochemically purify RNA granules from rat brain. Here, we identified a specific set of interactors for two RNA-binding proteins that are known components of neuronal RNA granules, Barentsz and Staufen2. First, neuronal RNA granules are much more heterogeneous than previously anticipated, sharing only a third of the identified proteins. Second, dendritically localized mRNAs, e.g., Arc and CaMKIIα, associate selectively with distinct RNA granules. Third, our work identifies a series of factors with known roles in RNA localization, translational control, and RNA quality control that are likely to keep localized transcripts in a translationally repressed state, often in distinct types of RNPs.

  20. Polycomb repressive complex 2 in embryonic stem cells: an overview.

    PubMed

    Jones, Amanda; Wang, Hengbin

    2010-12-01

    Polycomb Group Proteins (PcG) are a family of epigenetic regulators responsible for the repression of an array of genes important in development and cell fate specification. PcG proteins complex to form two types of epigenetic regulators: Polycomb Repressive Complex 1 and 2 (PRC1 and PRC2). Although the mechanisms regulating PRC2 recruitment and activity in mammals remain poorly understood, recent work has identified a non-canonical PRC2 in mouse embryonic stem cells (mESC) with unique activities required for repression of PRC2 target genes and necessary for mESC differentiation and somatic cell reprogramming. Here we review the functions of PRC2 in embryonic stem cells and explore the role of the newly identified mESC specific PRC2 regulatory subunits Jarid2 (jumonji, AT rich interactive domain 2), Mtf2 (metal response element binding transcription factor 2) and esPRC2p48.

  1. The co-pigmentation of anthocyanin isolated from mangosteen pericarp (Garcinia Mangostana L.) as Natural Dye for Dye- Sensitized Solar Cells (DSSC)

    NASA Astrophysics Data System (ADS)

    Munawaroh, H.; adillah, G. F.; Saputri, L. N. M. Z.; Hanif, Q. A.; Hidayat, R.; Wahyuningsih, S.

    2016-02-01

    Study of color stability of anthocyanin from extract mangosteen pericarp (Garcinia mangostana L.) with co-pigmentation method has been conducted. Malic acid and ascorbic acid used as a co-pigment to stabilize the anthocyanin structure through formation of new binding between anthocyanin. Anthocyanin from mangosteen pericarp were isolated by several steps, including maceration, extraction, and Thin Layer Chromatography (TLC). The anthocyanin separation was conducted by TLC, while the identification of functional groups of those compound, were used FTIR (Fourier Transform Infrared Spectroscopy) for spectra analysis. Ultraviolet- visible absorption spectra have represented differences absorbance and color intensity in various pH. Copigmentation with malic acid and ascorbic acid in many composition and temperature were also well described. Meanwhile, anthocyanin-malic acid and anthocyanin-ascorbic acid have color retention higher than that of pure anthocyanin. Maximum color retention has been achieved at a ratio of 1:3 and 1:5 for ascorbic acid and malic acid, respectively. Therefore, the addition of ascorbic acid and malic acid as a copigment shows the ability to protect color retention of anthocyanin (mangosteen pericarp) from degradation process. The better efficiency of DSSC (η) have been achieved, whereas n of controlled anthocyanin, anthocyanin-ascorbic acid, and anthocyanin-malic acid were 0,1996%, 0,2922%, 0,3029%, respectively.

  2. Paper Chromatography and UV-Vis Spectroscopy to Characterize Anthocyanins and Investigate Antioxidant Properties in the Organic Teaching Laboratory

    ERIC Educational Resources Information Center

    Galloway, Kelli R.; Bretz, Stacey Lowery; Novak, Michael

    2015-01-01

    A variety of fruits and vegetables, including raspberries, blueberries, Concord grapes, blackberries, strawberries, peaches, eggplant, red cabbage, and red onions, contain flavonoid compounds known as anthocyanins that are responsible for the blue-red color and the astringent taste associated with such foods. In addition, anthocyanins exhibit a…

  3. Glucose Sensor MdHXK1 Phosphorylates and Stabilizes MdbHLH3 to Promote Anthocyanin Biosynthesis in Apple

    PubMed Central

    Hu, Da-Gang; Zhang, Quan-Yan; An, Jian-Ping; You, Chun-Xiang; Hao, Yu-Jin

    2016-01-01

    Glucose induces anthocyanin accumulation in many plant species; however, the molecular mechanism involved in this process remains largely unknown. Here, we found that apple hexokinase MdHXK1, a glucose sensor, was involved in sensing exogenous glucose and regulating anthocyanin biosynthesis. In vitro and in vivo assays suggested that MdHXK1 interacted directly with and phosphorylated an anthocyanin-associated bHLH transcription factor (TF) MdbHLH3 at its Ser361 site in response to glucose. Furthermore, both the hexokinase_2 domain and signal peptide are crucial for the MdHXK1-mediated phosphorylation of MdbHLH3. Moreover, phosphorylation modification stabilized MdbHLH3 protein and enhanced its transcription of the anthocyanin biosynthesis genes, thereby increasing anthocyanin biosynthesis. Finally, a series of transgenic analyses in apple calli and fruits demonstrated that MdHXK1 controlled glucose-induced anthocyanin accumulation at least partially, if not completely, via regulating MdbHLH3. Overall, our findings provide new insights into the mechanism of the glucose sensor HXK1 modulation of anthocyanin accumulation, which occur by directly regulating the anthocyanin-related bHLH TFs in response to a glucose signal in plants. PMID:27560976

  4. Glucose Sensor MdHXK1 Phosphorylates and Stabilizes MdbHLH3 to Promote Anthocyanin Biosynthesis in Apple.

    PubMed

    Hu, Da-Gang; Sun, Cui-Hui; Zhang, Quan-Yan; An, Jian-Ping; You, Chun-Xiang; Hao, Yu-Jin

    2016-08-01

    Glucose induces anthocyanin accumulation in many plant species; however, the molecular mechanism involved in this process remains largely unknown. Here, we found that apple hexokinase MdHXK1, a glucose sensor, was involved in sensing exogenous glucose and regulating anthocyanin biosynthesis. In vitro and in vivo assays suggested that MdHXK1 interacted directly with and phosphorylated an anthocyanin-associated bHLH transcription factor (TF) MdbHLH3 at its Ser361 site in response to glucose. Furthermore, both the hexokinase_2 domain and signal peptide are crucial for the MdHXK1-mediated phosphorylation of MdbHLH3. Moreover, phosphorylation modification stabilized MdbHLH3 protein and enhanced its transcription of the anthocyanin biosynthesis genes, thereby increasing anthocyanin biosynthesis. Finally, a series of transgenic analyses in apple calli and fruits demonstrated that MdHXK1 controlled glucose-induced anthocyanin accumulation at least partially, if not completely, via regulating MdbHLH3. Overall, our findings provide new insights into the mechanism of the glucose sensor HXK1 modulation of anthocyanin accumulation, which occur by directly regulating the anthocyanin-related bHLH TFs in response to a glucose signal in plants. PMID:27560976

  5. The beet Y locus encodes an anthocyanin MYB-like protein that activates the betalain red pigment pathway.

    PubMed

    Hatlestad, Gregory J; Akhavan, Neda A; Sunnadeniya, Rasika M; Elam, Lee; Cargile, Scott; Hembd, Austin; Gonzalez, Antonio; McGrath, J Mitchell; Lloyd, Alan M

    2015-01-01

    Nearly all flowering plants produce red/violet anthocyanin pigments. Caryophyllales is the only order containing families that replace anthocyanins with unrelated red and yellow betalain pigments. Close biological correlation of pigmentation patterns suggested that betalains might be regulated by a conserved anthocyanin-regulating transcription factor complex consisting of a MYB, a bHLH and a WD repeat-containing protein (the MBW complex). Here we show that a previously uncharacterized anthocyanin MYB-like protein, Beta vulgaris MYB1 (BvMYB1), regulates the betalain pathway in beets. Silencing BvMYB1 downregulates betalain biosynthetic genes and pigmentation, and overexpressing BvMYB1 upregulates them. However, unlike anthocyanin MYBs, BvMYB1 will not interact with bHLH members of heterologous anthocyanin MBW complexes because of identified nonconserved residues. BvMYB1 resides at the historic beet pigment-patterning locus, Y, required for red-fleshed beets. We show that Y and y express different levels of BvMYB1 transcripts. The co-option of a transcription factor regulating anthocyanin biosynthesis would be an important evolutionary event allowing betalains to largely functionally replace anthocyanins. PMID:25436858

  6. Genetic analyses of anthocyanin concentrations and intensity of red bulb color among segregating haploid progenies of onion

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Higher concentrations of anthocyanins in vegetables are important for attractive appearance and may offer health benefits for consumers. The red color of onion bulbs is due primarily to the accumulation of anthocyanins. The goals of this study were to identify chromosome regions that condition yello...

  7. Gene regulation of anthocyanin biosynthesis in two blood-flesh peach (Prunus persica (L.) Batsch) cultivars during fruit development.

    PubMed

    Jiao, Yun; Ma, Rui-juan; Shen, Zhi-jun; Yan, Juan; Yu, Ming-liang

    2014-09-01

    The blood-flesh peach has become popular in China due to its attractive anthocyanin-induced pigmentation and antioxidant properties. In this study, we investigated the molecular mechanisms underlying anthocyanin accumulation by examining the expression of nine genes of the anthocyanin biosynthesis pathway found in the peach mesocarp. Expression was measured at six developmental stages in fruit of two blood-flesh and one white-flesh peach cultivars, using quantitative reverse transcription polymerase chain reaction (qRT-PCR). Results show that the expression of the chalcone synthase (CHS) gene was closely related to anthocyanin accumulation in both of the blood-flesh peaches. In the white-flesh peach, we found that the transcription level of phenylalanine ammonia-lyase (PAL) during fruit development was much lower than that in the blood-flesh peach, even though all other genes of the anthocyanin biosynthesis pathway were highly expressed, suggesting that the PAL gene may be limiting in anthocyanin production in the white-flesh peach. Moreover, the transcription levels of the CHS and UDP-glucose-flavonoid 3-O-glucosyltransferase (UFGT) genes were markedly up-regulated at three days after bag removal (DABR) in the blood-flesh peach, suggesting that CHS and UFGT are the key genes in the process of anthocyanin biosynthesis for both of the blood-flesh peaches. The present study will be of great help in improving understanding of the molecular mechanisms involved in anthocyanin accumulation in blood-flesh peaches.

  8. The beet Y locus encodes an anthocyanin-MYB-like protein that activates the betalain red pigment pathway

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Almost all flowering plants produce red/violet, phenylalanine-based, anthocyanin pigments. A single order, the Caryophyllales, contains families that replace anthocyanins with tyrosine-based red and yellow betalain pigments. Close biological correlation of pigmentation patterns suggested that betala...

  9. Anthocyanin-Rich Juice Lowers Serum Cholesterol, Leptin, and Resistin and Improves Plasma Fatty Acid Composition in Fischer Rats

    PubMed Central

    Graf, Daniela; Seifert, Stephanie; Jaudszus, Anke; Bub, Achim; Watzl, Bernhard

    2013-01-01

    Obesity and obesity-associated diseases e.g. cardiovascular diseases and type 2 diabetes are spread worldwide. Anthocyanins are supposed to have health-promoting properties, although convincing evidence is lacking. The aim of the present study was to investigate the effect of anthocyanins on several risk factors for obesity-associated diseases. Therefore, Fischer rats were fed anthocyanin-rich grape-bilberry juice or an anthocyanin-depleted control juice for 10 weeks. Intervention with anthocyanin-rich grape-bilberry juice reduced serum cholesterol and tended to decrease serum triglycerides. No effects were seen for serum non-esterified fatty acids, glucose, and insulin. Anthocyanin-rich grape-bilberry juice intervention reduced serum leptin and resistin, but showed no influence on serum adiponectin and secretion of adipokines from mesenteric adipose tissue. Furthermore, anthocyanin-rich grape-bilberry juice increased the proportion of polyunsaturated fatty acids and decreased the amount of saturated fatty acids in plasma. These results indicate that anthocyanins possess a preventive potential for obesity-associated diseases. PMID:23825152

  10. Transcriptional activation of a MYB gene controls the tissue-specific anthocyanin accumulation in a purple cauliflower mutant

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Flavonoids such as anthocyanins possess significant health benefits to humans and play important physiological roles in plants. An interesting Purple gene mutation in cauliflower confers an abnormal pattern of anthocyanin accumulation, giving intense purple color in very young leaves, curds, and see...

  11. The beet Y locus encodes an anthocyanin MYB-like protein that activates the betalain red pigment pathway.

    PubMed

    Hatlestad, Gregory J; Akhavan, Neda A; Sunnadeniya, Rasika M; Elam, Lee; Cargile, Scott; Hembd, Austin; Gonzalez, Antonio; McGrath, J Mitchell; Lloyd, Alan M

    2015-01-01

    Nearly all flowering plants produce red/violet anthocyanin pigments. Caryophyllales is the only order containing families that replace anthocyanins with unrelated red and yellow betalain pigments. Close biological correlation of pigmentation patterns suggested that betalains might be regulated by a conserved anthocyanin-regulating transcription factor complex consisting of a MYB, a bHLH and a WD repeat-containing protein (the MBW complex). Here we show that a previously uncharacterized anthocyanin MYB-like protein, Beta vulgaris MYB1 (BvMYB1), regulates the betalain pathway in beets. Silencing BvMYB1 downregulates betalain biosynthetic genes and pigmentation, and overexpressing BvMYB1 upregulates them. However, unlike anthocyanin MYBs, BvMYB1 will not interact with bHLH members of heterologous anthocyanin MBW complexes because of identified nonconserved residues. BvMYB1 resides at the historic beet pigment-patterning locus, Y, required for red-fleshed beets. We show that Y and y express different levels of BvMYB1 transcripts. The co-option of a transcription factor regulating anthocyanin biosynthesis would be an important evolutionary event allowing betalains to largely functionally replace anthocyanins.

  12. Nature's Swiss Army Knife: The Diverse Protective Roles of Anthocyanins in Leaves

    PubMed Central

    Gould, Kevin S.

    2004-01-01

    Anthocyanins, the pigments responsible for spectacular displays of vermilion in the leaves of deciduous trees, have long been considered an extravagant waste of a plant's resources. Contemporary research, in contrast, has begun to show that the pigments can significantly influence the way a leaf responds to environmental stress. Anthocyanins have been implicated in tolerance to stressors as diverse as drought, UV-B, and heavy metals, as well as resistance to herbivores and pathogens. By absorbing high-energy quanta, anthocyanic cell vacuoles both protect chloroplasts from the photoinhibitory and photooxidative effects of strong light, and prevent the catabolism of photolabile defence compounds. Anthocyanins also mitigate photooxidative injury in leaves by efficiently scavenging free radicals and reactive oxygen species. Far from being a useless by-product of the flavonoid pathway, these red pigments may in some instances be critical for plant survival. PMID:15577195

  13. Ultrasonic extraction of anthocyanin from Clitoria ternatea flowers using response surface methodology.

    PubMed

    Chong, Fui Chin; Gwee, Xian Fu

    2015-01-01

    The ultrasonic extraction (UE) method of anthocyanin from Clitoria ternatea flowers using response surface methodology (RSM) was performed in this study. By using RSM, the objective is to optimise the extraction yield of anthocyanin from C. ternatea which is influenced by various factors, including the extraction temperature, time, ratio of solvent to solid and ultrasonic power. The empirical model was investigated by performing first-level optimisation in a two-level factorial design with Design Expert 7 software. In comparison with the conventional solvent extraction, UE showed a 246.48% better extraction yield and produced an anthocyanin extract with a radical scavenging activity of 68.48% at the optimised factors of 50°C, 150 min, 15 mL/g and 240 W. PMID:25836369

  14. Nature's Swiss Army Knife: The Diverse Protective Roles of Anthocyanins in Leaves.

    PubMed

    Gould, Kevin S

    2004-01-01

    Anthocyanins, the pigments responsible for spectacular displays of vermilion in the leaves of deciduous trees, have long been considered an extravagant waste of a plant's resources. Contemporary research, in contrast, has begun to show that the pigments can significantly influence the way a leaf responds to environmental stress. Anthocyanins have been implicated in tolerance to stressors as diverse as drought, UV-B, and heavy metals, as well as resistance to herbivores and pathogens. By absorbing high-energy quanta, anthocyanic cell vacuoles both protect chloroplasts from the photoinhibitory and photooxidative effects of strong light, and prevent the catabolism of photolabile defence compounds. Anthocyanins also mitigate photooxidative injury in leaves by efficiently scavenging free radicals and reactive oxygen species. Far from being a useless by-product of the flavonoid pathway, these red pigments may in some instances be critical for plant survival.

  15. Effect of Blueberry Anthocyanins Malvidin and Glycosides on the Antioxidant Properties in Endothelial Cells.

    PubMed

    Huang, Wuyang; Zhu, Yunming; Li, Chunyang; Sui, Zhongquan; Min, Weihong

    2016-01-01

    The objective of this research was to survey the antioxidant functional role of the main anthocyanins of blueberries in endothelial cells. Changes on the reactive oxygen species (ROS), xanthine oxidase-1 (XO-1), superoxide dismutase (SOD), and heme oxygenase-1 (HO-1) in cells of malvidin and the two glycosides were investigated. The results showed that these anthocyanins decreased the levels of ROS and XO-1 but increased the levels of SOD and HO-1. Glycosides improved the antioxidant capacity of malvidin to a great extent. The changes in the antioxidant properties of malvidin-3-glucoside were more pronounced than malvidin-3-galactoside. Variation in levels of malvidin-3-glucoside and malvidin-3-galactoside had a significant impact on antioxidant properties to different extents. It indicates that blueberries are a good resource of anthocyanins, which can protect cells from oxidative deterioration and use blueberry as a potential functional food to prevent diseases related to oxidative stress. PMID:27034731

  16. Light signaling induces anthocyanin biosynthesis via AN3 mediated COP1 expression

    PubMed Central

    Meng, Lai-Sheng; Liu, Aizhong

    2015-01-01

    Light signaling plays a pivotal role in controlling plant morphogenesis, metabolism, growth and development. The central process of light signaling pathway is to build the link between light signals and the expression of genes involved. Although studies focused on light signaling toward metabolism have been documented well in the past several decades, most regulation networks of light signaling in a specific metabolic production largely remained unknown. Anthocyanin accumulation in plant tissues depends on the availability of light signals, but only little is known about the potential regulation network underlying light signal controls anthocyanin biosynthesis. Here, we briefly review the recent progress on the light-triggered anthocyanin biosynthesis via ANGUSTIFOLIA3 (AN3) and CONSTITUTIVE PHOTOMORPHOGENIC1 (COP1) network in Arabidopsis. PMID:26357851

  17. Anthocyanins and antioxidant capacities of six Chilean berries by HPLC-HR-ESI-ToF-MS.

    PubMed

    Ramirez, Javier E; Zambrano, Ricardo; Sepúlveda, Beatriz; Kennelly, Edward J; Simirgiotis, Mario J

    2015-06-01

    The HPLC profiles of six fruits endemic of the VIII region of Chile were investigated using high resolution mass analysis (HR-ToF-ESI-MS). The anthocyanin fingerprints generated for the fruits were compared and the antioxidant capacities measured by the scavenging of the DPPH radical, the ferric reducing antioxidant power (FRAP), the superoxide anion scavenging activity assay (SA), and correlated with the inhibition of lipid peroxidation in human erythrocytes (LP) and total content of phenolics, flavonoids and anthocyanins measured by spectroscopic methods. Several anthocyanins were identified, including 3-O-glycosides derivatives of delphinidin, cyanidin, petunidin, peonidin and malvidin. Three phenolic acids (feruloyl-quinic acid, chlorogenic acid, and neochlorogenic acid) and five flavonols (hyperoside, isoquercitrin, quercetin, rutin, myricetin and isorhamnetin) were also identified. Calafate fruits showed the highest antioxidant activity. However, the highest LP activity was found for Chilean blueberries (>95%) followed by calafate fruits (91.27%) and luma (83.4%). PMID:25624212

  18. Effect of Blueberry Anthocyanins Malvidin and Glycosides on the Antioxidant Properties in Endothelial Cells

    PubMed Central

    Huang, Wuyang; Zhu, Yunming; Li, Chunyang

    2016-01-01

    The objective of this research was to survey the antioxidant functional role of the main anthocyanins of blueberries in endothelial cells. Changes on the reactive oxygen species (ROS), xanthine oxidase-1 (XO-1), superoxide dismutase (SOD), and heme oxygenase-1 (HO-1) in cells of malvidin and the two glycosides were investigated. The results showed that these anthocyanins decreased the levels of ROS and XO-1 but increased the levels of SOD and HO-1. Glycosides improved the antioxidant capacity of malvidin to a great extent. The changes in the antioxidant properties of malvidin-3-glucoside were more pronounced than malvidin-3-galactoside. Variation in levels of malvidin-3-glucoside and malvidin-3-galactoside had a significant impact on antioxidant properties to different extents. It indicates that blueberries are a good resource of anthocyanins, which can protect cells from oxidative deterioration and use blueberry as a potential functional food to prevent diseases related to oxidative stress. PMID:27034731

  19. Anti-inflammatory and antioxidative activity of anthocyanins from purple basil leaves induced by selected abiotic elicitors.

    PubMed

    Szymanowska, Urszula; Złotek, Urszula; Karaś, Monika; Baraniak, Barbara

    2015-04-01

    This paper investigates changes in the anti-inflammatory and antioxidative activity of anthocyanins from purple basil (Ocimum basilicum L.) leaves induced by arachidonic acid (AA), jasmonic acid (JA) and β-aminobutyric acid (BABA). The anthocyanins content was significantly increased by all elicitors used in this study; however, no increase was observed in the antioxidant activity of the analyzed extracts. Additionally, a significant decrease by about 50% in the ability to chelate Fe(II) was noted. Further, an increase in the potential anti-inflammatory activity of basil anthocyanins was observed after treatment with each the abiotic elicitor. The IC50 value for lipoxygenase inhibition was almost twice as low after elicitation as that of the control. Also, cyclooxygenase inhibition by anthocyanins was stimulated by abiotic elicitors, except for JA-sample. Additionally, HPLC-analysis indicated that elicitation with AA, JA and BABA caused increases in content most of all anthocyanin compounds.

  20. Heat stability of strawberry anthocyanins in model solutions containing natural copigments extracted from rose (Rosa damascena Mill.) petals.

    PubMed

    Shikov, Vasil; Kammerer, Dietmar R; Mihalev, Kiril; Mollov, Plamen; Carle, Reinhold

    2008-09-24

    Thermal degradation and color changes of purified strawberry anthocyanins in model solutions were studied upon heating at 85 degrees C by HPLC-DAD analyses and CIELCh measurements, respectively. The anthocyanin half-life values increased significantly due to the addition of rose (Rosa damascena Mill.) petal extracts enriched in natural copigments. Correspondingly, the color stability increased as the total color difference values were smaller for anthocyanins upon copigment addition, especially after extended heating. Furthermore, the stabilizing effect of rose petal polyphenols was compared with that of well-known copigments such as isolated kaempferol, quercetin, and sinapic acid. The purified rose petal extract was found to be a most effective anthocyanin-stabilizing agent at a molar pigment/copigment ratio of 1:2. The results obtained demonstrate that the addition of rose petal polyphenols slows the thermal degradation of strawberry anthocyanins, thus resulting in improved color retention without affecting the gustatory quality of the product.

  1. Heat stability of strawberry anthocyanins in model solutions containing natural copigments extracted from rose (Rosa damascena Mill.) petals.

    PubMed

    Shikov, Vasil; Kammerer, Dietmar R; Mihalev, Kiril; Mollov, Plamen; Carle, Reinhold

    2008-09-24

    Thermal degradation and color changes of purified strawberry anthocyanins in model solutions were studied upon heating at 85 degrees C by HPLC-DAD analyses and CIELCh measurements, respectively. The anthocyanin half-life values increased significantly due to the addition of rose (Rosa damascena Mill.) petal extracts enriched in natural copigments. Correspondingly, the color stability increased as the total color difference values were smaller for anthocyanins upon copigment addition, especially after extended heating. Furthermore, the stabilizing effect of rose petal polyphenols was compared with that of well-known copigments such as isolated kaempferol, quercetin, and sinapic acid. The purified rose petal extract was found to be a most effective anthocyanin-stabilizing agent at a molar pigment/copigment ratio of 1:2. The results obtained demonstrate that the addition of rose petal polyphenols slows the thermal degradation of strawberry anthocyanins, thus resulting in improved color retention without affecting the gustatory quality of the product. PMID:18729376

  2. Characterization and quantification of anthocyanins in selected artichoke (Cynara scolymus L.) cultivars by HPLC-DAD-ESI-MSn.

    PubMed

    Schütz, Katrin; Persike, Markus; Carle, Reinhold; Schieber, Andreas

    2006-04-01

    The anthocyanin pattern of artichoke heads (Cynara scolymus L.) has been investigated by high-performance liquid chromatography-electrospray ionization mass spectrometry. For this purpose a suitable extraction and liquid chromatographic method was developed. Besides the main anthocyanins-cyanidin 3,5-diglucoside, cyanidin 3-glucoside, cyanidin 3,5-malonyldiglucoside, cyanidin 3-(3''-malonyl)glucoside, and cyanidin 3-(6''-malonyl)glucoside-several minor compounds were identified. Among these, two peonidin derivatives and one delphinidin derivative were characterized on the basis of their fragmentation patterns. To the best of our knowledge this is the first report on anthocyanins in artichoke heads consisting of aglycones other than those of cyanidin. Quantification of individual compounds was performed by external calibration. Cyanidin 3-(6''-malonyl)glucoside was found to be the major anthocyanin in all the samples analyzed. Total anthocyanin content ranged from 8.4 to 1,705.4 mg kg(-1) dry mass.

  3. Synthesis and characterization of Allium cepa L. as photosensitizer of dye-sensitized solar cell

    NASA Astrophysics Data System (ADS)

    Sutikno, Afrian, Noverdi; Supriadi, Putra, Ngurah Made Dharma

    2016-04-01

    The synthesis and characterization of Allium cepa L. used as natural pigment for natural dye sensitizer of solar cell has successfully done and anthocyanin is extracted. Anthocynin is color pigment of plant which has characteristic absorption spectrum of photon and excites electrons up to pigment molecules. As the anthocyanin absorbed light increases the excited electrons increase as well. The generated current also increases and it leads to the efficiency increase. The energy conversion efficiency of the cells sensitized with dye of Allium cepa L. was 3,045 x 10-4%. A simple technique was taken to fabricate dye sensitizer solar cell is spincoating.

  4. Ultraviolet A-specific induction of anthocyanin biosynthesis in the swollen hypocotyls of turnip (Brassica rapa).

    PubMed

    Zhou, Bo; Li, Yuhua; Xu, Zhiru; Yan, Haifang; Homma, Shinichiro; Kawabata, Saneyuki

    2007-01-01

    Ultraviolet A (UV-A)-mediated regulation of anthocyanin biosynthesis was investigated in swollen hypocotyls of the red turnip 'Tsuda'. The shaded swollen hypocotyls which contained negligible anthocyanin were exposed to artificial light sources including low fluence UV-B, UV-A, blue, red, far-red, red plus UV-A, far-red plus UV-A, and blue plus red. Among these lights, only UV-A induced anthocyanin biosynthesis and co-irradiation of red or far-red with UV-A did not affect the extent of UV-A-induced anthocyanin accumulation. The expression of phenylalanine ammonia lyase (PAL; EC 4.3.1.5), chalcone synthase (CHS; EC 2.3.1.74), flavanone 3-hydroxylase (F3H; EC 1.14.11.9), dihydroflavonol 4-reductase (DFR; EC 1.1.1.219), and anthocyanidin synthase (ANS; EC 1.14.11.19) genes was increased with time during a 24 h exposure to UV-A. In contrast, irradiation with red, blue, UV-B, and a combination of blue with red failed to induce CHS expression. Microarray analysis showed that only a few genes, including CHS and F3H, were induced significantly by UV-A, while a separate set of many genes was induced by low fluence UV-B. The UV-A-specific induction of anthocyanin biosynthesis and the unique gene expression profile upon UV-A irradiation as compared with blue and UV-B demonstrated that the observed induction of anthocyanin biosynthesis in red turnips was mediated by a distinct UV-A-specific photoreceptor, but not by phytochromes, UV-A/blue photoreceptors, or UV-B photoreceptors.

  5. Relationship of light quantity and anthocyanin production in Pennisetum setaceum Cvs. rubrum and red riding hood.

    PubMed

    Beckwith, Andrea G; Zhang, Yanjun; Seeram, Navindra P; Cameron, Arthur C; Nair, Muraleedharan G

    2004-02-11

    Pennisetum setaceum cvs. Rubrum and Red Riding Hood are purple-pigmented ornamental grasses when grown in high-light environments. In low-light environments, foliage appears light purple or green, and as a result, aesthetic appeal is reduced. The impact of light on anthocyanin pigmentation was compared for P. setaceum Rubrum foliage and flowers and Red Riding Hood foliage grown under different light intensities and light sources. Light environments included UV supplemental light in the greenhouse, high-pressure sodium supplemental light in the greenhouse, cool-white fluorescent light in a growth chamber, and full sun outside. Anthocyanins in two cultivars of P. setaceum were analyzed by HPLC and characterized by (1)H and (13)C NMR spectral experiments. Two anthocyanins, cyanidin 3-glucoside and cyanidin 3-rutinoside, were identified in the leaves and flowers of both cultivars and quantified by HPLC analysis. The major anthocyanin in both cultivars was cyanidin 3-glucoside and had highest concentration (0.199% fresh weight) in Rubrum leaves grown under fluorescent lights in the growth chamber with a photoperiod of 24 h and a daily light integral (DLI) of 13.3 mol m(-)(2) day(-)(1) and in Rubrum and Red Riding Hood leaves and flowers (0.097 and 0.12% fresh weight) from plants grown outside in full sun with a photoperiod ranging from 15 to 13.5 h and DLI of 42 mol m(-)(2) day(-)(1). The minor anthocyanin, cyanidin 3-rutinoside, had the highest quantity in plants grown in low-light-intensity greenhouse environments with a photoperiod ranging from 15 to 13.5 h and DLI of 2.3-7.0 mol m(-)(2) day(-)(1). The functional significance of anthocyanins in P. setaceum Rubrum is discussed.

  6. Identification of anthocyanins in black soybean (Glycine max (L.) Merr.) varieties.

    PubMed

    Koh, Kwangoh; Youn, Jung Eun; Kim, Hee-Seon

    2014-02-01

    Anthocyanin pigments in black soybean (Glycine max (L.) Merr.) varieties as Tawonkong (TW) and Geomjeongkong-2 (G2) were identified to evaluate their potentials as nutritional function, natural colorant or functional foods. Anthocyanin extraction was conducted with acidified methanol with 0.1 M HCl (85:15, v/v). Identification of anthocyanin was conducted by comparison with purified standards by HPLC and mass spectrometry (MS). G2 showed six different types of pigments by HPLC, whereas TW showed seven pigments. Three major anthocyanins (peaks 1, 3, 4) were detected in both varieties and peak 1 was characterized as delphinidin-3-O-β-D-glucoside, peak 3 as cyanidin-3-O-β-D-glucoside (C3G), and peak 4 as petunidin-3-O-β-D-glucoside by comparison of chromatographic properties with authentic standards and MS. Minor peaks 5, 6 and 7 in TW were tentatively identified as pelargonidin-3-O-glucoside, pelargonidin-3-O-(6″-malonylglucoside) and cyanidin on the basis of MS. MS with major ions at 287 and 449 of peak 2 were exactly same as those of peak 3 meaning that peak 2 has cyanidin and other hexose different from glucose. After acid hydrolysis of fractioned peak 2, HPLC showed the hexose as galactose, and peak 2 was identified as C3Glactose. The most abundant anthocyanin in black soybean (Glycine max (L.) Merr.) was C3G and G2 showed the higher amount of total anthocyanins than TW (p < 0.001).

  7. Ginkgo biloba extract and bilberry anthocyanins improve visual function in patients with normal tension glaucoma.

    PubMed

    Shim, Seong Hee; Kim, Joon Mo; Choi, Chul Young; Kim, Chan Yun; Park, Ki Ho

    2012-09-01

    Ginkgo biloba extract (GBE) and anthocyanins are considered beneficial for various vascular diseases. This study was performed to evaluate the effect of GBE and anthocyanins on visual function in patients with normal tension glaucoma (NTG) based on the vascular theory of mechanisms of glaucomatous optic nerve damage. Retrospective analysis was carried out by a chart review of 332 subjects (209 men and 123 women) who were treated with anthocyanins (n=132), GBE (n=103), or no medication (control, n=97). Humphrey Visual Field (HVF) test, logarithm of the minimal angle of resolution best-corrected visual acuity (logMAR BCVA), intraocular pressure, blood pressure, and fasting blood glucose were determined before and after treatment. Complete ocular and systemic examinations were performed. The mean follow-up duration was 23.82±9.84 (range, 12-59) months; the mean anthocyanin treatment duration was 24.32±10.43 (range, 6-53) months, and the mean GBE treatment duration was 23.81±10.36 months (range, 6-59) months. After anthocyanin treatment, the mean BCVA for all eyes improved from 0.16 (±0.34) to 0.11 (±0.18) logMAR units (P=.008), and HVF mean deviation improved from -6.44 (±7.05) to -5.34 (±6.42) (P=.001). After GBE treatment, HVF mean deviation improved from -5.25 (±6.13) to -4.31 (±5.60) (P=.002). A generalized linear model demonstrated that the final BCVA was not affected by demographic differences among the groups. These results suggest that anthocyanins and GBE may be helpful in improving visual function in some individuals with NTG. PMID:22870951

  8. CCoAOMT Down-Regulation Activates Anthocyanin Biosynthesis in Petunia.

    PubMed

    Shaipulah, Nur Fariza M; Muhlemann, Joëlle K; Woodworth, Benjamin D; Van Moerkercke, Alex; Verdonk, Julian C; Ramirez, Aldana A; Haring, Michel A; Dudareva, Natalia; Schuurink, Robert C

    2016-02-01

    Anthocyanins and volatile phenylpropenes (isoeugenol and eugenol) in petunia (Petunia hybrida) flowers have the precursor 4-coumaryl coenzyme A (CoA) in common. These phenolics are produced at different stages during flower development. Anthocyanins are synthesized during early stages of flower development and sequestered in vacuoles during the lifespan of the flowers. The production of isoeugenol and eugenol starts when flowers open and peaks after anthesis. To elucidate additional biochemical steps toward (iso)eugenol production, we cloned and characterized a caffeoyl-coenzyme A O-methyltransferase (PhCCoAOMT1) from the petals of the fragrant petunia 'Mitchell'. Recombinant PhCCoAOMT1 indeed catalyzed the methylation of caffeoyl-CoA to produce feruloyl CoA. Silencing of PhCCoAOMT1 resulted in a reduction of eugenol production but not of isoeugenol. Unexpectedly, the transgenic plants had purple-colored leaves and pink flowers, despite the fact that cv Mitchell lacks the functional R2R3-MYB master regulator ANTHOCYANIN2 and has normally white flowers. Our results indicate that down-regulation of PhCCoAOMT1 activated the anthocyanin pathway through the R2R3-MYBs PURPLE HAZE (PHZ) and DEEP PURPLE, with predominantly petunidin accumulating. Feeding cv Mitchell flowers with caffeic acid induced PHZ expression, suggesting that the metabolic perturbation of the phenylpropanoid pathway underlies the activation of the anthocyanin pathway. Our results demonstrate a role for PhCCoAOMT1 in phenylpropene production and reveal a link between PhCCoAOMT1 and anthocyanin production. PMID:26620524

  9. Effects of Anthocyanin on Serum Lipids in Dyslipidemia Patients: A Systematic Review and Meta-Analysis

    PubMed Central

    Lu, Yan; Bo, Yacong

    2016-01-01

    Background Dyslipidemia was present in most of the patients with coronary heart disease. Epidemiological evidence suggests that anthocyanin has some effects on the serum lipid. However, these results are controversial. This study aimed at collecting current clinical evidence and evaluating the effects of anthocyanin supplementation on total cholesterol (TC), triglyceride (TG), low-density lipoprotein cholesterol (LDL-C), and high-density lipoprotein cholesterol (HDL-C) in dialysis patients. Methods The search included PubMed, Web of Science, MEDLINE, Cochrane Library, China National Knowledge Infrastructure, Wanfang Database (up to July 2015) to identify randomized controlled trials (RCTs) on the association between anthocyanin and serum lipids. RevMan (version 5.2) was used for Meta-analysis. Meta-regression analysis, sensitivity analysis and Egger’s weighted regression tests were performed by using STATA software (version 12.0; StatCorp, College Station, TX, USA). Results Six studies (seven arms) involving 586 subjects were included in this meta-analysis. The results showed that anthocyanin supplementation has significant effects on TC [MD = -24.06, 95% CI(-45.58 to -2.64) mg/dL, I2 = 93%], TG [MD = -26.14, 95%CI(-40.20 to -3.08) mg/dL, I2 = 66%1], LDL-C [MD = -22.10, 95% CI (-34.36 to -9.85) mg/dL, I2 = 61%], and HDL-C(MD = 5.58, 95% CI (1.02 to 10.14) mg/dL;I2 = 90%). Conclusion Anthocyanin supplementation significantly reduces serum TC, TG, and LDL-C levels in patients with dyslipidemia, and increases HDL-C. Further rigorously designed RCTs with larger sample sizes are needed to confirm the effectiveness of anthocyanin supplementation for dyslipidemia, especially hypo high density lipoprotein cholesterolemia. PMID:27589062

  10. A MYB transcription factor regulates anthocyanin biosynthesis in mangosteen (Garcinia mangostana L.) fruit during ripening.

    PubMed

    Palapol, Yossapol; Ketsa, Saichol; Lin-Wang, Kui; Ferguson, Ian B; Allan, Andrew C

    2009-05-01

    Mangosteen (Garcinia mangostana L.) fruit undergo rapid red colour development, both on the tree and after harvest, resulting in high anthocyanin production in the pericarp. Here, we report the isolation of three full-length mangosteen MYB transcription factors (GmMYB1, GmMYB7 and GmMYB10) and all the anthocyanin biosynthetic pathway genes (GmPal to GmUFGT). Phylogenetic analysis at the protein level of the R2R3-MYB transcription factor family showed GmMYB10 had a high degree of similarity with production of anthocyanin pigment1 in Arabidopsis and as well as sequences from other plant species related to the elevation of anthocyanin pigmentation. In transient transactivation assays, GmMYB10, co-expressed with AtbHLH2, strongly activated the GmDFR and AtDFR promoters. Transcripts of GmMYB10 and GmUFGT were highly abundant with onset of pigmentation and subsequently during red colouration. Our results suggest that GmMYB10 plays an important role in regulating anthocyanin biosynthesis both on the tree and after harvest, while GmUFGT may be a key biosynthetic gene in mangosteen pigmentation. The expression patterns of GmMYB10 and GmUFGT correlated with ethylene production that increased linearly until stage 5 (dark purple) and decreased thereafter. 1-Methycyclopropene (1-MCP) clearly delayed red colouration with resulting down-regulation of GmMYB10. These results suggest that the effect of ethylene on anthocyanin biosynthesis may be via the regulation of GmMYB10 expression.

  11. Anthocyanin and Carotenoid Contents in Different Cultivars of Chrys