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Sample records for acylated flavonol glycosides

  1. A new acylated flavonol glycoside from Derris triofoliata.

    PubMed

    Xu, Lu-Rong; Wu, Jun; Zhang, Si

    2006-01-01

    A new acylated flavonol glycoside, kaempferol 3-O-[(6''''-feruloyl)-beta-D-glucopyranosyl-(1 --> 3)]-[alpha-L-rhamnopyranosyl-(1 --> 6)]-beta-D-glucopyranoside and two known cyclolignan glycosides, (+)-lyoniresinol-3alpha-O-beta-D-glucopyranoside and ( - )-lyoniresinol-3alpha-O-beta-D-glucopyranoside were isolated from n-BuOH extracts of the aerial parts of Derris triofoliata, their structures were determined from spectroscopic and chemical evidences.

  2. Acylated flavonol glycosides from Tagetes minuta with antibacterial activity.

    PubMed

    Shahzadi, Irum; Shah, Mohammad M

    2015-01-01

    Wild marigold (Tagetes minuta), a flowering plant of the family Asteraceae contains compounds of pharmaceutical and nutritional importance especially essential oils and flavonols. Identification, characterization of flavonols and determination of their antibacterial activity were major objectives of the current study. The isolation and purification of flavonols was accomplished using chromatographic techniques while structural elucidation was completed by LC-MS and NMR spectroscopy. The extracts and purified compounds were tested against various bacterial strains for antibacterial activity. A total of 19 flavonols were isolated from this species. Of these, 17 were of butanol and two of ethyl acetate extracts. Based on the concentration and purity, eight potential flavonols were selected and structurally elucidated. Four flavonols, 6-hydroxyquercetin 7-O-β-(6''-galloylglucopyranoside; 2), 6-hydroxykaempferol 7-O-β-glucopyranoside (5), 6-hydroxykaempferol 7-O-β-(6''-galloylglucopyranoside; 7), 6-hydroxyquercetin 7-O-β-(6''-caffeoylglucopyranoside; 9), were identified for the first time from T. minuta. Butanol and ethyl acetate extracts of flowers and seeds showed significant antibacterial activity against Micrococcus leteus, Staphylococcus aureus, Bacillus subtilis, and Pseudomonas pikettii. Among the isolated flavonols only 1, 2, and 18 were found to possess significant antibacterial activity against M. luteus. The extracts and purified flavonols from T. minuta can be potential candidates for antibacterial drug discovery and support to ethnopharmacological use. PMID:26441652

  3. Acylated flavonol glycosides from Tagetes minuta with antibacterial activity

    PubMed Central

    Shahzadi, Irum; Shah, Mohammad M.

    2015-01-01

    Wild marigold (Tagetes minuta), a flowering plant of the family Asteraceae contains compounds of pharmaceutical and nutritional importance especially essential oils and flavonols. Identification, characterization of flavonols and determination of their antibacterial activity were major objectives of the current study. The isolation and purification of flavonols was accomplished using chromatographic techniques while structural elucidation was completed by LC–MS and NMR spectroscopy. The extracts and purified compounds were tested against various bacterial strains for antibacterial activity. A total of 19 flavonols were isolated from this species. Of these, 17 were of butanol and two of ethyl acetate extracts. Based on the concentration and purity, eight potential flavonols were selected and structurally elucidated. Four flavonols, 6-hydroxyquercetin 7-O-β-(6′′-galloylglucopyranoside; 2), 6-hydroxykaempferol 7-O-β-glucopyranoside (5), 6-hydroxykaempferol 7-O-β-(6′′-galloylglucopyranoside; 7), 6-hydroxyquercetin 7-O-β-(6′′-caffeoylglucopyranoside; 9), were identified for the first time from T. minuta. Butanol and ethyl acetate extracts of flowers and seeds showed significant antibacterial activity against Micrococcus leteus, Staphylococcus aureus, Bacillus subtilis, and Pseudomonas pikettii. Among the isolated flavonols only 1, 2, and 18 were found to possess significant antibacterial activity against M. luteus. The extracts and purified flavonols from T. minuta can be potential candidates for antibacterial drug discovery and support to ethnopharmacological use. PMID:26441652

  4. Rare syringyl acylated flavonol glycosides from the aerial parts of Leonurus japonicus Houtt.

    PubMed

    Zhang, Yi; Deng, Shen; Qu, Lu; An, Ya-Ting; Wu, Chun-Hua; Han, Li-Feng; Gao, Xiu-Mei; Wang, Tao

    2013-01-01

    Five new syringyl acylated flavonol glycosides, named leonurusoides A (1), B (2), C (3), D (4), and E (5), together with one known one 6 were obtained from the aerial parts of Leonurus japonicus. Their structures were elucidated by chemical and spectroscopic methods (UV, IR, HRESI-TOF-MS, 1D and 2D NMR). Compounds 1-6 showed triglyceride (TG) accumulation inhibitory effects in free fatty acid-induced HepG2 cells.

  5. New Acylated Flavonol Glycosides and a Phenolic Profile of Pritzelago alpina, a Forgotten Edible Alpine Plant.

    PubMed

    Corradi, Elisabetta; De Mieri, Maria; Cadisch, Larissa; Abbet, Christian; Hamburger, Matthias; Potterat, Olivier

    2016-02-01

    Thirteen acylated flavonoid glycosides, 1-13, including eleven new congeners, 3-13, were isolated from the aerial parts of Pritzelago alpina (Brassicaceae) by a combination of column chromatography on Sephadex LH-20, and preparative and semi-preparative HPLC. The structures were established by extensive NMR and MS experiments in combination with acid hydrolysis and sugar analysis by GC/MS. The new compounds were shown to be kaempferol and quercetin glycosides acylated for most of them by a branched short chain fatty acid or a hydroxycinnamic acid residue on the sugar portion. As shown by a HPLC-DAD analysis of a MeOH extract, these compounds are the main phenolic constituents in the aerial parts of the plant. PMID:26880431

  6. Flavonol Glycosides from Gaura Biennis

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Phytochemical investigation of the native American plant Gaura biennis led to the isolation of three new flavonol glycosides (1-3), along with eight known ones. Their structures were established primarily by spectroscopic data as quercetin 3-O-(2"-O-a-L-rhamnopyranosyl-6"-O-E-p-coumaroyl)-ß-D- gluco...

  7. Flavonol glycosides from Calotropis gigantea.

    PubMed

    Sen, S; Sahu, N P; Mahato, S B

    1992-08-01

    Besides isolation and characterization of isorhamnetin-3-O-rutinoside, isorhamnetin-3-O-glucopyranoside and taraxasteryl acetate, a new flavonol trisaccharide was isolated from the aerial parts of Calotropis gigantea, and its structure was established as isorhamnetin-3-O-[2-O-beta-D-galactopyranosyl-6-O-alpha-L-rhamnopy ranosyl]- beta-D-glucopyranoside by a combination of fast atom bombardment mass spectroscopy, 1H and 13C NMR spectra and some chemical degradations.

  8. Malonylated flavonol glycosides from the petals of Clitoria ternatea.

    PubMed

    Kazuma, Kohei; Noda, Naonobu; Suzuki, Masahiko

    2003-01-01

    Three flavonol glycosides, kaempferol 3-O-(2"-O-alpha-rhamnosyl-6"-O-malonyl)-beta-glucoside, quercetin 3-O-(2"-O-alpha-rhamnosyl-6"-O-malonyl)-beta-glucoside, and myricetin 3-O-(2",6"-di-O-alpha-rhamnosyl)-beta-glucoside were isolated from the petals of Clitoria ternatea cv. Double Blue, together with eleven known flavonol glycosides. Their structures were identified using UV, MS, and NMR spectroscopy. They were characterized as kaempferol and quercetin 3-(2(G)- rhamnosylrutinoside)s, kaempferol, quercetin, and myricetin 3-neohesperidosides, 3-rutinosides, and 3-glucosides in the same tissue. In addition, the presence of myricetin 3-O-(2"-O-alpha-rhamnosyl-6"-O-malonyl)-beta-glucoside was inferred from LC/MS/MS data for crude petal extracts. The flavonol compounds identified in the petals of C. ternatea differed from those reported in previous studies. PMID:12482461

  9. Flavonol glycosides in the petal of Rosa species as chemotaxonomic markers.

    PubMed

    Sarangowa, Ochir; Kanazawa, Tsutomu; Nishizawa, Makoto; Myoda, Takao; Bai, Changxi; Yamagishi, Takashi

    2014-11-01

    Thirteen flavonol glycosides were isolated from the petals of Rosa species belonging to the section Gallicanae, and their structures were identified from their spectroscopic data. These flavonol glycosides, along with two flavonol glycosides isolated from Rosa rugosa, in the petals of 31 Rosa species belonging to sections Gallicanae, Cinnamomeae, Caninae, and Synstylae were quantitatively analyzed by UPLC. The results indicated that the species belonging to these sections could be classified into four types (Type A, B, C and D) based on the pattern of flavonol glycoside contents, whereas the R. rugosa flavonol glycosides were detected only in section Cinnamomeae. A principal components analysis (PCA) calculated from the 15 flavonol glycosides contained in these samples supported the presence of four types. The distribution of the species in Type D (a group of Cinnamomeae) was shown to reflect close interrelationships, but species in Type B (one group of Gallicanae) could be subdivided into two groups, one of which contained species in section Synstylae. Moreover, the flavonol glycosides were grouped by sugar moieties: a disaccharide composed of two hexoses (S1), a hexose (S2), including a hexose with galloyl group, a pentose (S3), and a disaccharide composed of a hexose and a pentose (S4). The ratios of the amounts of S1-S4 to total flavonol glycoside content indicated that differences among the four sections were more distinctive than the amounts of the 15 flavonol glycosides. The 31 samples were divided into Type B, composed of one type of Gallicanae and Synstylae, Type A+C, composed of another type of Gallicanae and Caninae, and Type D, composed of Cinnamomeae. The R. rugosa flavonol glycosides were shown to be important chemotaxonomic markers for the classification of species in Cinnamomeae, and this method of using flavonol glycosides as chemotaxonomic markers could be useful for the identification of Rosa species belonging to sections Gallicanae, Cinnamomeae

  10. FLAVONOL GLYCOSIDES FROM THE NATIVE AMERICAN PLANT GAURA LONGIFLORA

    PubMed Central

    Xu, Wen-Hui; Jacob, Melissa R.; Agarwal, Ameeta K.; Clark, Alice M.; Liang, Zong-Suo; Li, Xing-Cong

    2013-01-01

    Phytochemical investigation of the native American plant Gaura longiflora led to the isolation of three new and eight known flavonol glycosides. The structures of the new compounds were established primarily by spectroscopic data as quercetin 3-O-(2″-O-α-l-rhamnopyranosyl-6″-O-E-p-coumaroyl)-β-D-glucopyranoside (1), kaempferol 3-O-(2″-O-α-l-rhamnopyranosyl-6″-O-E-p-coumaroyl)-β-d-gluco-pyranoside (2) and quercetin 3-O-(2″-O-α-l-rhamnopyranosyl-6″-O-Z-p-coumaroyl)-β-D-glucopyrano-side (3). PMID:24371369

  11. Quantification of flavonol glycosides in Camellia sinensis by MRM mode of UPLC-QQQ-MS/MS.

    PubMed

    Wu, Yahui; Jiang, Xiaolan; Zhang, Shuxiang; Dai, Xinlong; Liu, Yajun; Tan, Huarong; Gao, Liping; Xia, Tao

    2016-04-01

    Phenolic compounds are major components of tea flavour, in which catechins and flavonol glycosides play important roles in the astringent taste of tea infusion. However, the flavonol glycosides are difficult to quantify because of the large variety, as well as the inefficient seperation on chromatography. In this paper, a total of 15 flavonol glycosides in the tea plant (Camellia sinensis) were identified by the high performance liquid chromatography (HPLC) coupled to a time-of-flight mass spectrometer (TOF-MS), and a quantitative method was established based on multiple reaction monitoring (MRM) mode of ultra-high performance liquid chromatography (UPLC) coupled to a triple quadrupole mass spectrometer (QQQ-MS/MS). It provided the limit of detection and quantification to the order of picogram, which was more sensitive than the HPLC detection of the order of nanogram. The relative standard deviations of the intra- and inter-day variations in retention time and signal intensity (peak area) of six analytes were less than 0.26% and 4%, respectively. The flavonol glycosides of four tea cultivars were relatively quantified using the signal intensity (peak area) of product ion, in which six flavonol glycosides were quantified by the authentic standards. The results showed that the flavonol mono-, di- and tri-glycoside mostly accumulated in young leaves of the four tea cultivars. Notably, the myricetin 3-O-galactoside was the major component among the six flavonol glycosides detected.

  12. Four new flavonol glycosides from the leaves of Brugmansia suaveolens.

    PubMed

    Geller, Fabiana; Murillo, Renato; Steinhauser, Lisa; Heinzmann, Berta; Albert, Klaus; Merfort, Irmgard; Laufer, Stefan

    2014-01-01

    Four new flavonol glycosides were isolated from the leaves of Brugmansia suaveolens: kaempferol 3-O-β-D-glucopyranosyl-(1'''→2'')-O-α-L-arabinopyranoside (1), kaempferol 3-O-β-D-glucopyranosyl-(1'''→2'')-O-α-L-arabinopyranoside-7-O-į-D-gluco-pyranoside (2), kaempferol 3-O-β-D-[6'''-O-(E-caffeoyl)]-glucopyranosyl-(1'''→2'')-O-α-l-arabinopyranoside-7-O-β-D-glucopyranoside (3), and kaempferol 3-O-β-D-[2'''-O-(E-caffeoyl)]-glucopyranosyl-(1'''→2'')-O-α-l-arabinopyranoside-7-O-β-D-glucopyranoside (4). The structure elucidation was performed by MS, 1D and 2D NMR analyses. PMID:24858103

  13. Isolation and antioxidant activity of galloyl flavonol glycosides from the seashore plant, Pemphis acidula.

    PubMed

    Masuda, T; Iritani, K; Yonemori, S; Oyama, Y; Takeda, Y

    2001-06-01

    Four kinds of galloyl flavonol glycosides were found in the leaf extract of Pemphis acidula, a plant growing on the subtropical seashore. Their chemical structures were elucidated to be quercetin or kaempferol 6"-O-galloyl-beta-D-glycosides by using spectroscopic and chemical analyses. One of the flavonols, kaempferol-3-O-(6-O-galloyl-beta-D-galactopyranoside), was newly isolated from natural sources and its structure was completely determined in this investigation. The antioxidant-related activities of the galloyl flavonoids were examined by the DPPH antiradical activity, inhibition of methyl linoleate oxidation, and inhibition of oxidative cell death. These results were compared with those of the corresponding non-galloylated flavonol glycosides and their aglycones. The galloyl flavonoids showed more efficient activity than that of the corresponding flavonol glycosides, but not more than that of the corresponding aglycones in the three assays applied.

  14. Analysis of supercooling-facilitating (anti-ice nucleation) activity of flavonol glycosides.

    PubMed

    Kasuga, Jun; Fukushi, Yukiharu; Kuwabara, Chikako; Wang, Donghui; Nishioka, Atsushi; Fujikawa, Emiko; Arakawa, Keita; Fujikawa, Seizo

    2010-04-01

    Deep supercooling xylem parenchyma cells (XPCs) of katsura tree (Cercidiphyllum japonicum) contain four kinds of flavonol glycosides with high supercooling-facilitating (anti-ice nucleation) activities. These flavonol glycosides have very similar structures, but their supercooling-facilitating activities are very different. In this study, we analyzed the supercooling-facilitating activities of 12 kinds of flavonol glycosides in order to determine the chemical structures that might affect supercooling-facilitating activity. All of the flavonol glycosides tested showed supercooling-facilitating activity, although the magnitudes of activity differed among the compounds. It was clear that the combination of the position of attachment of the glycosyl moiety, the kind of attached glycosyl moiety and the structure of aglycone determined the magnitude of anti-ice nucleation activity. However, there is still some ambiguity preventing the exact identification of features that affect the magnitude of supercooling-facilitating activity.

  15. [Determination of 7 flavonol glycosides in Ginkgo biloba reference extract].

    PubMed

    Wang, Jing-hui; Chen, Jing; Wang, Meng-meng; Fu, Xin-tong; Chen, You-gen; Guo, Hong-zhu

    2015-10-01

    Six flavonol glycosides were isolated and calibrated from Ginkgo biloba extract, and then used to calibrate the content in 2 baiches of G. biloba reference extract, so was rutin. RSD values of rutin, kaempferol-3-O-rutinoside, kaempferol-3-O-rhamnoside-2-glu- coside, quercetin-3-O-rhamnop-yranosyl-2-O-(6-O-p-coumaroyl)-glucoside, kaempferol-3-O-rhamnopyranosyl-2-O-(6-O-p-coum-aroyl) - glucoside were around 1.1%-4.6%, nevertheless, RSD values of quercetin-3-O-glucoside and isorhamnetin-3-O-rutinoside were more than 5%. According to the results, the reference extract of G. biloba can be used as the substitute to determine rutin, kaempferol-3-O- rutinoside, kaempferol-3-O-rhamnoside-2-glucoside, quercetin-3-O-rhamnopyranosyl-2-O-(6-O-p-coumaroyl)-glucoside and kaempferol-3-0-rhamnopyranosyl-2-O-(6-O-p-coumaroyl)-glucoside instead of corresponding reference substances. So reference extract in place of single component reference in assay is feasible. PMID:27062820

  16. [Determination of 7 flavonol glycosides in Ginkgo biloba reference extract].

    PubMed

    Wang, Jing-hui; Chen, Jing; Wang, Meng-meng; Fu, Xin-tong; Chen, You-gen; Guo, Hong-zhu

    2015-10-01

    Six flavonol glycosides were isolated and calibrated from Ginkgo biloba extract, and then used to calibrate the content in 2 baiches of G. biloba reference extract, so was rutin. RSD values of rutin, kaempferol-3-O-rutinoside, kaempferol-3-O-rhamnoside-2-glu- coside, quercetin-3-O-rhamnop-yranosyl-2-O-(6-O-p-coumaroyl)-glucoside, kaempferol-3-O-rhamnopyranosyl-2-O-(6-O-p-coum-aroyl) - glucoside were around 1.1%-4.6%, nevertheless, RSD values of quercetin-3-O-glucoside and isorhamnetin-3-O-rutinoside were more than 5%. According to the results, the reference extract of G. biloba can be used as the substitute to determine rutin, kaempferol-3-O- rutinoside, kaempferol-3-O-rhamnoside-2-glucoside, quercetin-3-O-rhamnopyranosyl-2-O-(6-O-p-coumaroyl)-glucoside and kaempferol-3-0-rhamnopyranosyl-2-O-(6-O-p-coumaroyl)-glucoside instead of corresponding reference substances. So reference extract in place of single component reference in assay is feasible.

  17. Flavonol Glycosides from the Leaves of Allium macrostemon.

    PubMed

    Nakane, Risa; Iwashina, Tsukasa

    2015-08-01

    Twelve flavonoids were isolated from Allium macrostemon leaves. Five compounds were identified as kaempferol 3,7-di-O-glucoside (1), kaempferol 3,4'-di-O-glucoside (2), quercetin 3-O-glucoside (3), kaempferol 3-0-glucoside (4) and isorhamnetin 3-O-glucoside (5) by UV spectra, LC-MS, acid hydrolysis and HPLC comparisons with authentic standards. Other flavonoids were characterized as kaempferol glycosides (6-8, 10 and 11) and quercetin glycosides (9 and 12). Other compounds, such as steroidal saponins, have been already found from the bulbs of A. macrostemon. However, flavonoids were reported for the first time from the leaves. PMID:26434122

  18. Flavonol glycosides from the aerial parts of Gynostemma pentaphyllum and their antioxidant activity.

    PubMed

    Jang, Hari; Lee, Jin Woo; Lee, Chul; Jin, Qinghao; Lee, Myung Koo; Lee, Chong Kil; Lee, Mi Kyeong; Hwang, Bang Yeon

    2016-09-01

    The phytochemical investigation of the aerial parts of Gynostemma pentaphyllum led to the isolation of a new flavonol glycoside, gynopentaphylloside (1), along with seven known compounds (2-8). The structure of the new compound was determined on the basis of 1D, 2D NMR and HRESIMS data as well as acid hydrolysis. The antioxidant activity of the isolates was evaluated by a 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical scavenging assay. PMID:27384065

  19. Sedative activity of two flavonol glycosides isolated from the flowers of Albizzia julibrissin Durazz.

    PubMed

    Kang, T H; Jeong, S J; Kim, N Y; Higuchi, R; Kim, Y C

    2000-07-01

    The flowers of Albizzia julibrissin are used as a sedative in oriental traditional medicine. The phytochemical study of this plant allowed the isolation of two flavonol glycosides, quercitrin (1) and isoquercitrin (2). The sedative activity of these compounds was evaluated, and both compounds 1 and 2 increased pentobarbital-induced sleeping time in dose-dependent manner in mice. These results support the use of the flowers of this plant as a sedative agent. PMID:10904180

  20. A new flavonol glycoside from the florets of Carthamus tinctorius L.

    PubMed

    Xie, Xue; Zhou, Jianming; Sun, Lin; Zhang, Hongda; Zhao, Yiwu; Song, Yaling; Wang, Xuejing; Ni, Fuyong; Huang, Wenzhe; Wang, Zhenzhong; Xiao, Wei

    2016-01-01

    One new flavonol glycoside, 6-hydroxykaempferol-3-O-β-D-glucoside-7-O-β-D-glucuronide (1), together with eight known flavonoids and three known quinochalcones, was isolated from the florets of Carthamus tinctorius L. Their structures were determined by extensive spectroscopic analyses. Their cardioprotective effects against H2O2-induced apoptosis in H9c2 cells were also evaluated; compounds 1, 2, 4-5, 7-10 and 12 provided significant protective effects on H2O2-induced H9c2 cells at the concentration of 25 μg/mL.

  1. A new flavonol glycoside from the florets of Carthamus tinctorius L.

    PubMed

    Xie, Xue; Zhou, Jianming; Sun, Lin; Zhang, Hongda; Zhao, Yiwu; Song, Yaling; Wang, Xuejing; Ni, Fuyong; Huang, Wenzhe; Wang, Zhenzhong; Xiao, Wei

    2016-01-01

    One new flavonol glycoside, 6-hydroxykaempferol-3-O-β-D-glucoside-7-O-β-D-glucuronide (1), together with eight known flavonoids and three known quinochalcones, was isolated from the florets of Carthamus tinctorius L. Their structures were determined by extensive spectroscopic analyses. Their cardioprotective effects against H2O2-induced apoptosis in H9c2 cells were also evaluated; compounds 1, 2, 4-5, 7-10 and 12 provided significant protective effects on H2O2-induced H9c2 cells at the concentration of 25 μg/mL. PMID:26185946

  2. A general approach to quantification of hydroxycinnamic acid derivatives and flavones, flavonols, and their glycosides by UV spectrophotometry

    Technology Transfer Automated Retrieval System (TEKTRAN)

    A general method was developed for the quantification of hydroxycinnamic acid derivatives and flavones, flavonols, and their glycosides based on the UV molar relative response factors (MRRF) of the standards. Each of these phenolic compounds contains a cinnamoyl structure and has a maximum absorban...

  3. [Determination of flavonol glycosides in tea samples by ultra-high performance liquid chromatography-photodiode array detection-tandem mass spectrometry].

    PubMed

    Wang, Zhicong; Sha, Yuebing; Yu, Xiaobo; Liang, Yuerong

    2015-09-01

    An ultra-high performance liquid chromatography-photodiode array detection-tandem mass spectrometry (UPLC-PDA-MS/MS) method was developed for the determination of flavonol glycosides in tea samples. The chromatographic separation was performed on an UPLC HSS T3 column by gradient elution with the mobile phases of acetonitrile and water both containing 0.1% (v/v) formic acid. A total of 15 flavonol glycosides which include 3 myricetin glycosides, 6 quercetin glycosides and 6 kaempferol glycosides were positively identified in green and black tea samples by comparing the retention times and mass spectra of the samples with standards and publications. The quantities of flavonol glycosides were relatively calculated with the stand- ard quercetin-3-rhamnosylglucoside (Q-GRh) which was calibrated with external quantification method using multi-reaction monitoring (MRM) mode. The results showed that there were different flavonol glycoside distributions in green tea and black tea. The total amount of flavonol glycosides in green tea was 1. 7 times of that in black tea. The major flavonol glycosides in green tea were myricetin-3-galactoside (M-Ga), myricetin-3-glucoside (M-G), quercetin-3-glucosyl-rhamnosyl-galactoside (Q-GaRhG), quercetin-3-glucosyl-rhamnosyl-glucoside (Q-GRhG), kaempferol-3-glucosyl-rhamnosyl-galactoside (K-GaRhG) and kaempferol-3-glucosyl- rhamnosyl-glucoside (K-GRhG), but for black tea, the major flavonol glycosides were quercetin-3-rhamnosylglucoside (Q-GRh), quercetin-3-glucoside (Q-G), kaempferol-3-rhamnosylglucoside (K-GRh) and kaempferol-3-galactoside (K-Ga). The present method is accurate, convenient for the rapid identification of flavonol glycosides and analysis of constituent distribution for green and black teas.

  4. Acylated flavonol tri- and tetraglycosides in the flavonoid metabolome of Cladrastis kentukea (Leguminosae).

    PubMed

    Kite, Geoffrey C; Rowe, Emily R; Lewis, Gwilym P; Veitch, Nigel C

    2011-04-01

    The foliar metabolome of Cladrastis kentukea (Leguminosae) contains a complex mixture of flavonoids including acylated derivatives of the 3-O-rhamnosyl(1→2)[rhamnosyl(1→6)]-galactosides of kaempferol and quercetin and their 7-O-rhamnosides, together with an array of non-acylated kaempferol and quercetin di-, tri- and tetraglycosides. Thirteen of the acylated flavonoids, 12 of which had not been reported previously, were characterised by spectroscopic and chemical methods. Eight of these were the four isomers of kaempferol 3-O-α-l-rhamnopyranosyl(1→2)[α-l-rhamnopyranosyl(1→6)]-(3/4-O-E/Z-p-coumaroyl-β-d-galactopyranoside) and their 7-O-α-l-rhamnopyranosides, and three were isomers of quercetin 3-O-α-l-rhamnopyranosyl(1→2)[α-l-rhamnopyranosyl(1→6)]-(3/4-O-E/Z-p-coumaroyl-β-d-galactopyranoside) - the remaining 4Z isomer was identified by LC-UV-MS analysis of a crude extract. The final two acylated flavonoids characterised by NMR were the 3E and 4E isomers of kaempferol 3-O-α-l-rhamnopyranosyl(1→2)[α-l-rhamnopyranosyl(1→6)]-(3/4-O-E-feruloyl-β-d-galactopyranoside)-7-O-α-l-rhamnopyranoside while the 3Z and 4Z isomers were again detected by LC-UV-MS. Using the observed fragmentation behaviour of the isolated compounds following a variety of MS experiments, a further 18 acylated flavonoids were given tentative structures by LC-MS analysis of a crude extract. Acylated flavonoids were absent from the flowers of C. kentukea, which contained an array of non-acylated kaempferol and quercetin glycosides. Immature fruits contained kaempferol 3-O-α-rhamnopyranosyl(1→2)[α-rhamnopyranosyl(1→6)]-β-galactopyranoside and its 7-O-α-rhamnopyranoside as the major flavonoids with acylated flavonoids, different from those in the leaves, only present as minor constituents. The presence of acylated flavonoids distinguishes the foliar flavonoid metabolome of C. kentukea from that of a closely related legume, Styphnolobium japonicum, which contains a similar

  5. Antiviral effect of flavonol glycosides isolated from the leaf of Zanthoxylum piperitum on influenza virus.

    PubMed

    Ha, Song-Yi; Youn, Hana; Song, Chang-Seon; Kang, Se Chan; Bae, Jong Jin; Kim, Hee Tae; Lee, Kwang Min; Eom, Tae Hoon; Kim, In Su; Kwak, Jong Hwan

    2014-04-01

    The ethanol extract of Zanthoxylum piperitum (L.) DC. showed in vitro antiviral activity against influenza A virus. Three flavonol glycosides were isolated from the EtOAc fraction of Z. piperitum leaf by means of activity-guided chromatographic separation. Structures of isolated compounds were identified as quercetin 3-O-β-D-galactopyranoside (1), quercetin 3-O-α-L-rhamnopyranoside (2), kaempferol 3-O-α-L-rhamnopyranoside (3) by comparing their spectral data with literature values. The anti-influenza viral activity of isolates was evaluated using a plaque reduction assay against influenza A/NWS/33 (H1N1) virus. The compounds also were subjected to neuraminidase inhibition assay in influenza A/NWS/33 virus. Compounds 1-3 exhibited antiviral activity against an influenza A virus in vitro, and inhibited the neuraminidase activity at relatively high concentrations.

  6. Additional antiprotozoal flavonol glycosides of the aerial parts of Helianthemum glomeratum.

    PubMed

    Calzada, Fernando; Alanís, Alma Delia

    2007-01-01

    Bioassay-guided fractionation of the methanol extract of aerial parts from Helianthemum glomeratum afforded five antiprotozoal flavonol glycosides: tiliroside, kaempferol-3-O-(3'',6''di-O-E-p-coumaroyl)-betad-glucopyranoside, astragalin, quercitrin and isoquercitrin. The in vitro antiprotozoal assay showed that tiliroside was the most potent antiamoebic and antigiardial compound with IC(50) values of 17.5 microg/mL for Entamoeba histolytica and 17.4 microg/mL for G. lamblia. Isoquercitrin showed selectivity against E. histolytica (IC(50) 14.7 microg/mL) and quercitrin toward G. lamblia (IC(50) 24.3 microg/mL). All isolated compounds were less active than metronidazole and emetine, two antiprotozoal drugs used as positive controls.

  7. New flavonol glycosides from the leaves and flowers of Primula sieboidii.

    PubMed

    Hashimoto, Nana; Ohsawa, Ryo; Kitajima, Junichi; Iwashina, Tsukasa

    2015-03-01

    Three flavonol glycosides were isolated from the leaves of Primula sieboldii. They were identified as quercetin 3-O-β-[xylopyranosyl-(1-->2)-β- glucopyranosyl-(1-->6)-β-glucopyranoside] (1), kaempferol 3-O-β-[glucopyranosyl-(1-->2)-β-glucopyranosyl-(1-->6)-β-glucopyranoside] (2) and kaempferol 3- O-β-[xylopyranosyl-(1-->2)-β-glucopyranosyl-(1-->6)-β-glucopyranoside] (3). Their chemical structures were determined by UV, 1H and 13C NMR spectroscopy, LC-MS and acid hydrolysis. Compounds 1 and 3 are found in nature for the first time. They were also detected in the flowers, together with two anthocyanins, malvidin 3,5-di-O-glucoside and a minor petunidin dihexoside.

  8. Change of supercooling capability in solutions containing different kinds of ice nucleators by flavonol glycosides from deep supercooling xylem parenchyma cells in trees.

    PubMed

    Kuwabara, Chikako; Kasuga, Jun; Wang, Donghui; Fukushi, Yukiharu; Arakawa, Keita; Koyama, Toshie; Inada, Takaaki; Fujikawa, Seizo

    2011-12-01

    Deep supercooling xylem parenchyma cells (XPCs) in Katsura tree contain flavonol glycosides with high supercooling-facilitating capability in solutions containing the ice nucleation bacterium (INB) Erwinia ananas, which is thought to have an important role in deep supercooling of XPCs. The present study, in order to further clarify the roles of these flavonol glycosides in deep supercooling of XPCs, the effects of these supercooling-facilitating (anti-ice nucleating) flavonol glycosides, kaempferol 3-O-β-D-glucopyranoside (K3Glc), kaempferol 7-O-β-D-glucopyranoside (K7Glc) and quercetin 3-O-β-D-glucopyranoside (Q3Glc), in buffered Milli-Q water (BMQW) containing different kinds of ice nucleators, including INB Xanthomonas campestris, silver iodide and phloroglucinol, were examined by a droplet freezing assay. The results showed that all of the flavonol glycosides promoted supercooling in all solutions containing different kinds of ice nucleators, although the magnitudes of supercooling capability of each flavonol glycoside changed in solutions containing different kinds of ice nucleators. On the other hand, these flavonol glycosides exhibited complicated nucleating reactions in BMQW, which did not contain identified ice nucleators but contained only unidentified airborne impurities. Q3Glc exhibited both supercooling-facilitating and ice nucleating capabilities depending on the concentrations in such water. Both K3Glc and K7Glc exhibited only ice nucleation capability in such water. It was also shown by an emulsion freezing assay in BMQW that K3Glc and Q3Glc had no effect on homogeneous ice nucleation temperature, whereas K7Glc increased ice nucleation temperature. The results indicated that each flavonol glycoside affected ice nucleation by very complicated and varied reactions. More studies are necessary to determine the exact roles of these flavonol glycosides in deep supercooling of XPCs in which unidentified heterogeneous ice nucleators may exist.

  9. Change of supercooling capability in solutions containing different kinds of ice nucleators by flavonol glycosides from deep supercooling xylem parenchyma cells in trees.

    PubMed

    Kuwabara, Chikako; Kasuga, Jun; Wang, Donghui; Fukushi, Yukiharu; Arakawa, Keita; Koyama, Toshie; Inada, Takaaki; Fujikawa, Seizo

    2011-12-01

    Deep supercooling xylem parenchyma cells (XPCs) in Katsura tree contain flavonol glycosides with high supercooling-facilitating capability in solutions containing the ice nucleation bacterium (INB) Erwinia ananas, which is thought to have an important role in deep supercooling of XPCs. The present study, in order to further clarify the roles of these flavonol glycosides in deep supercooling of XPCs, the effects of these supercooling-facilitating (anti-ice nucleating) flavonol glycosides, kaempferol 3-O-β-D-glucopyranoside (K3Glc), kaempferol 7-O-β-D-glucopyranoside (K7Glc) and quercetin 3-O-β-D-glucopyranoside (Q3Glc), in buffered Milli-Q water (BMQW) containing different kinds of ice nucleators, including INB Xanthomonas campestris, silver iodide and phloroglucinol, were examined by a droplet freezing assay. The results showed that all of the flavonol glycosides promoted supercooling in all solutions containing different kinds of ice nucleators, although the magnitudes of supercooling capability of each flavonol glycoside changed in solutions containing different kinds of ice nucleators. On the other hand, these flavonol glycosides exhibited complicated nucleating reactions in BMQW, which did not contain identified ice nucleators but contained only unidentified airborne impurities. Q3Glc exhibited both supercooling-facilitating and ice nucleating capabilities depending on the concentrations in such water. Both K3Glc and K7Glc exhibited only ice nucleation capability in such water. It was also shown by an emulsion freezing assay in BMQW that K3Glc and Q3Glc had no effect on homogeneous ice nucleation temperature, whereas K7Glc increased ice nucleation temperature. The results indicated that each flavonol glycoside affected ice nucleation by very complicated and varied reactions. More studies are necessary to determine the exact roles of these flavonol glycosides in deep supercooling of XPCs in which unidentified heterogeneous ice nucleators may exist. PMID

  10. Flavonol glycosides in berries of two major subspecies of sea buckthorn (Hippophaë rhamnoides L.) and influence of growth sites.

    PubMed

    Ma, Xueying; Laaksonen, Oskar; Zheng, Jie; Yang, Wei; Trépanier, Martin; Kallio, Heikki; Yang, Baoru

    2016-06-01

    Flavonol glycosides of wild sea buckthorn (Hippophaë rhamnoides ssp. sinensis) berries from China and cultivated berries (H. rhamnoides ssp. mongolica) from Finland and Canada were identified and quantified. Twenty-six flavonol glycosides were found with isorhamnetin and quercetin as the major aglycones. The contents of flavonol glycosides ranged 23-250 mg/100 g fresh berries and were significantly higher in the berries of ssp. sinensis than in those of ssp. mongolica. Among the cultivars of ssp. mongolica, the berries of 'Oranzhevaya' had the lowest (23 mg/100 g) content, and those of 'Prevoshodnaya' the highest content of flavonol glycosides (80 mg/100 g). Within the ssp. mongolica, the samples from Kittilä (Northern Finland) had higher levels of most flavonol glycosides than those from Turku (Southern Finland) and Québec. Among the ssp. sinensis berries of different growth sites, increasing trends were detected in the contents of most of the compounds as the altitude increased and as the latitude decreased. The wild berries (ssp. sinensis) from Sichuan had remarkably high contents and unique profiles of flavonol glycosides. PMID:26830578

  11. Low and moderate photosynthetically active radiation affects the flavonol glycosides and hydroxycinnamic acid derivatives in kale (Brassica oleracea var. sabellica) dependent on two low temperatures.

    PubMed

    Neugart, Susanne; Fiol, Michaela; Schreiner, Monika; Rohn, Sascha; Zrenner, Rita; Kroh, Lothar W; Krumbein, Angelika

    2013-11-01

    Kale (Brassica oleracea var. sabellica) contains a large number of naturally occurring structurally different non-acylated and acylated flavonol glycosides as well as hydroxycinnamic acid derivatives. The objective of this study was to determine the effect of low and moderate photosynthetic active radiation (PAR) and how these levels interact with low temperature in these phenolic compounds. Juvenile kale plants were treated with PAR levels from 200 to 800 μmol m(-2) s(-1) at 5 and 10 °C under defined conditions in climate chambers. Of the investigated 20 compounds, 11 and 17 compounds were influenced by PAR and temperature, respectively. In addition, an interaction between PAR and temperature was found for eight compounds. The response of the phenolic compounds to PAR was structure-dependent. While quercetin triglycosides increased with higher PAR at 5 and 10 °C, the kaempferol triglycosides exhibited the highest concentrations at 400 μmol m(-2) s(-1). In contrast, kaempferol diglycosides exhibited the highest concentrations at increased PAR levels of 600 and 800 μmol m(-2) s(-1) at 10 °C. However, key genes of flavonol biosynthesis were influenced by temperature but remained unaffected by PAR. Furthermore, there was no interaction between the PAR level and the low temperature in the response of hydroxycinnamic acid derivatives in kale with the exception of caffeoylquinic acid, which decreased with higher PAR levels of 600 and 800 μmol m(-2) s(-1) and at a lower temperature. In conclusion, PAR and its interaction with temperature could be a suitable tool for modifying the profile of phenolic compounds.

  12. A new flavonol glycoside and activity of compounds from the flower of Nymphaea candida.

    PubMed

    Liu, R-N; Wang, W; Ding, Y; Xie, W-D; Ma, C; Du, L-J

    2007-01-01

    A new compound, kaempferol 3-O-(2''-O-galloylrutinoside) (1), was isolated from the white flower of Nymphaea candida, together with nine known flavonol glycosides, kaempferol (2), kaempferol 3-O-beta-D-glucopyranoside (3), kaempferol 3-O-alpha-l-rhamnopyranoside (4), kaempferol 3-O-alpha-l-rhamnopyranosylglucopyranoside (5), kaempferol 7-O-beta-D-glucopyranoside 3-(O-alpha-l-rhamnopyranosylglucopyranoside) (6), quercetin (7), quercetin 3-O-beta-D-xylopyranoside (8), myricetin (9), myricetin 3'-O-beta-D-xylopyranoside (10). The structure of 1 was established on the basis of the analysis of its 1D and 2D NMR spectral data. Compounds 1-7 and 9 exhibited moderate to significant antioxidant activities, which were evaluated by measurement of low-density lipoprotein (LDL) and malondialdehyde (MDA) levels in vitro. Compounds 1, 3, 4, 6 and 9 exhibited promising neuroprotective effects on ischemic injury model of cultured rat cortical neurons treated with sodium dithionite in glucose-free medium. Furthermore, compounds 1, 5, and 9 had distinct cytotoxicity to adrenal gland pheochromocytoma, PC12 cells, being treated by the same way. PMID:17613618

  13. Flavonol Glycosides in Currant Leaves and Variation with Growth Season, Growth Location, and Leaf Position.

    PubMed

    Yang, Wei; Alanne, Aino-Liisa; Liu, Pengzhan; Kallio, Heikki; Yang, Baoru

    2015-10-28

    Flavonol glycosides (FG) were analyzed in the leaves of six currant cultivars (Ribes spp.) with HPLC-DAD, HPLC-MS/MS, and NMR. The average amounts of the 12 major, identified FG constituted 86-93% (9.6-14.1 mg/g DW) of the total of 27 FG found. Quercetin and kaempferol were the major aglycones with trace amounts of myricetin. Quercetin-3-O-(2,6-α-dirhamnopyranosyl-β-glucopyranoside), quercetin-3-O-(2-β-xylopyranosyl-6-α-rhamnopyranosyl-β-glucopyranoside), and kaempferol-3-O-(3,6-α-dirhamnopyranosyl-β-glucopyranoside) were identified for the first time in currant leaves and existed in a white currant cultivar 'White Dutch' only. Kaempferol-3-O-β-(6'-malonyl)glucopyranoside was also a new compound existing in abundance in five cultivars but not in the white one. The results show the primary importance of the genetic background of the cultivars. The content of malonylated FG of special importance in cardiovascular health decreased regularly during summer. Time of collection and leaf position were more prominent factors affecting the composition than were the year of harvest or the growth latitude. Randomly collected leaves differed in their FG profiles from those collected from the middle position of new branches.

  14. Flavonol glycosides and other phenolic compounds in buds and leaves of different varieties of black currant (Ribes nigrum L.) and changes during growing season.

    PubMed

    Liu, Pengzhan; Kallio, Heikki; Yang, Baoru

    2014-10-01

    Phenolic compounds in buds and leaves of three varieties of black currant in Finland were identified by HPLC-DAD-ESI-MS/MS. Forty-three phenolic compounds of flavonol glycosides, proanthocyanidins and phenolic acids were found in variety "Mikael" whereas only thirty-five in "Mortti" and "Jaloste n:o 15". Glycosides of quercetin and kaempferol were the major phenolics. Rutin, hyperoside, isoquercitrin, kaempferol-3-O-rutinoise, kaempferol-3-O-glucoside, quercetin-3-O-(6″-malonyl)-glucoside and a kaempferol-malonylhexoside were the most abundant flavonol glycosides. The contents of flavonol glycosides ranged from 1 to 7 mg/g fresh weight in leaves showing typically an increasing trend from July to August, reaching the highest values in early October in "Mikael" and the end of August in "Mortti" and "Jaloste n:o 15". This is the first systematic report of the composition and content of phenolic compounds in buds and leaves of black currant.

  15. Improved cryopreservation by diluted vitrification solution with supercooling-facilitating flavonol glycoside.

    PubMed

    Kami, Daisuke; Kasuga, Jun; Arakawa, Keita; Fujikawa, Seizo

    2008-12-01

    The effect of kaempferol-7-O-glucoside (KF7G), one of the supercooling-facilitating flavonol glycosides which was originally found in deep supercooling xylem parenchyma cells of the katsura tree and was found to exhibit the highest level of supercooling-facilitating activity among reported substances, was examined for successful cryopreservation by vitrification procedures, with the aim of determining the possibility of using diluted vitrification solution (VS) to reduce cryoprotectant toxicity and also to inhibit nucleation at practical cooling and rewarming by the effect of supplemental KF7G. Examination was performed using shoot apices of cranberry and plant vitrification solution 2 (PVS2) with dilution. Vitrification procedures using the original concentration (100%) of PVS2 caused serious injury during treatment with PVS2 and resulted in no regrowth after cooling and rewarming (cryopreservation). Dilution of the concentration of PVS2 to 75% or 50% (with the same proportions of constituents) significantly reduced injury by PVS2 treatment, but regrowth was poor after cryopreservation. It is thought that dilution of PVS2 reduced injury by cryoprotectant toxicity, but such dilution caused nucleation during cooling and/or rewarming, resulting in poor survival. On the other hand, addition of 0.5mg/ml (0.05% w/v) KF7G to the diluted PVS2 resulted in significantly (p<0.05) higher regrowth rates after cryopreservation. It is thought that addition of supercooling-facilitating KF7G induced vitrification even in diluted PVS2 probably due to inhibition of ice nucleation during cooling and rewarming and consequently resulted in higher regrowth. The results of the present study indicate the possibility that concentrations of routinely used VSs can be reduced by adding supercooling-facilitating KF7G, by which more successful cryopreservation might be achieved for a wide variety of biological materials.

  16. Gmelinosides A-L, twelve acylated iridoid glycosides from Gmelina arborea.

    PubMed

    Hosny, M; Rosazza, J P

    1998-06-26

    Besides the known iridoids 6-O-alpha-L-rhamnopyranosylcatalpol (1), 6-O-(3"-O-trans-feruloyl)-alpha-L-rhamnopyranosylcatalpol (14), 6-O-(2"-O-acetyl-3", 4"-O-di-trans-cinnamoyl)-alpha-L-rhamnopyranosylcatalpol (15) and the known phenylpropanoid glycosides verbascoside (acteoside) and martynoside, 12 new acylated iridoid glycosides named gmelinosides A-L (2-13) have been isolated from the leaves of Gmelina arborea. These compounds were structurally characterized using a variety of spectral methods. PMID:9644056

  17. Novel flavonol glycosides from the aerial parts of lentil (Lens culinaris).

    PubMed

    Żuchowski, Jerzy; Pecio, Łukasz; Stochmal, Anna

    2014-11-06

    While the phytochemical composition of lentil (Lens culinaris) seeds is well described in scientific literature, there is very little available data about secondary metabolites from lentil leaves and stems. Our research reveals that the aerial parts of lentil are a rich source of flavonoids. Six kaempferol and twelve quercetin glycosides were isolated, their structures were elucidated using NMR spectroscopy and chemical methods. This group includes 16 compounds which have not been previously described in the scientific literature: quercetin 3-O-β-D-glucopyranosyl(1→2)-β-D-galactopyranoside-7-O-β-D-glucuropyranoside (1), kaempferol 3-O-β-D-glucopyranosyl(1→2)-β-D-galacto-pyranoside-7-O-β-D-glucuropyranoside (3), their derivatives 4-10,12-15,17,18 acylated with caffeic, p-coumaric, ferulic, or 3,4,5-trihydroxycinnamic acid and kaempferol 3-O-{[(6-O-E-p-coumaroyl)-β-D-glucopyranosyl(1→2)]-α-L-rhamnopyranosyl(1→6)}-β-D-galactopyranoside-7-O-α-L-rhamnopyranoside (11). Their DPPH scavenging activity was also evaluated. This is probably the first detailed description of flavonoids from the aerial parts of lentil.

  18. Hepatoprotective effect of flavonol glycosides rich fraction from Egyptian Vicia calcarata Desf. against CCl4-induced liver damage in rats.

    PubMed

    Singab, Abdel Nasser B; Youssef, Diaa T A; Noaman, Eman; Kotb, Saeed

    2005-07-01

    The hepatoprotective activity of flavonol glycosides rich fraction (F-2), prepared from 70% alcohol extract of the aerial parts of V. calcarata Desf., was evaluated in a rat model with a liver injury induced by daily oral administration of CCl4 (100 mg/kg, b.w) for four weeks. Treatment of the animals with F-2 using a dose of (25 mg/kg, b.w) during the induction of hepatic damage by CCl4 significantly reduced the indices of liver injuries. The hepatoprotective effects of F-2 significantly reduced the elevated levels of the following serum enzymes: alanine aminotransferase (ALT), aspartate aminotransferase (AST), alkaline phosphatase (ALP) and lactate dehydrogenase (LDH). The antioxidant activity of F-2 markedly ameliorated the antioxidant parameters including glutathione (GSH) content, glutathione peroxidase (GSH-Px), superoxide dismutase (SOD), plasma catalase (CAT) and packed erythrocytes glucose-6-phosphate dehydrogenase (G6PDH) to be comparable with normal control levels. In addition, it normalized liver malondialdehyde (MDA) levels and creatinine concentration. Chromatographic purification of F-2 resulted in the isolation of two flavonol glycosides that rarely occur in the plant kingdom, identified as quercetin-3, 5-di-O-beta-D-diglucoside (5) and kaempferol-3, 5-di-O-beta-D-diglucoside (4) in addition to the three known compounds identified as quercetin-3-O-alpha-L-rhamnosyl- (1-->6)-beta-D-glucoside [rutin, 3], quercetin-3-O-beta-D-glucoside [isoquercitrin, 2] and kaempferol-3-O-beta-D-glucoside [astragalin, 1]. These compounds were identified based on interpretation of their physical, chemical, and spectral data. Moreover, the spectrophotometric estimation of the flavonoids content revealed that the aerial parts of the plant contain an appreciable amount of flavonoids (0.89%) calculated as rutin. The data obtained from this study revealed that the flavonol glycosides of F-2 protect the rat liver from hepatic damage induced by CCl4 through inhibition of

  19. Isolation and purification of ginkgo flavonol glycosides from Ginkgo biloba leaves by high-speed counter-current chromatography.

    PubMed

    Zhang, Qiang; Chen, Li-Juan; Ye, Hao-Yu; Gao, Lei; Hou, Wenli; Tang, Minghai; Yang, Guangli; Zhong, Zhenhua; Yuan, Yuan; Peng, Aihua

    2007-08-01

    A high-speed counter-current chromatography method was developed for the separation and purification of bioactive flavonol glycosides from a crude ethanol extract of Ginkgo biloba leaves. The separation was performed with a two-phase solvent system composed of n-hexane-butanol-ethyl acetate-methanol-0.5% acetic acid (1:0.5:3.5:1:4, v/v) and three pure compounds were eluted in high purities in a one-step separation. Their purities were determined by HPLC and identified by MS,(1)H-NMR, and(13)C-NMR.

  20. Determination of flavonol glycosides in green tea, oolong tea and black tea by UHPLC compared to HPLC.

    PubMed

    Jiang, Heyuan; Engelhardt, Ulrich H; Thräne, Claudia; Maiwald, Beate; Stark, Janina

    2015-09-15

    An UHPLC method for the determination of flavonol glycosides (FOG) from green and oolong tea vs. black tea has been developed for the first time. Sample clean-up method by means of polyamide column chromatography was optimized with multiple-step elution. Using UHPLC and HPLC with gradient elution and photodiode array detection, eighteen FOG compounds were determined with the aid of electrospray tandem mass spectrometry. These FOG compounds were qualified on both UHPLC and HPLC, and this UHPLC method successfully separated rutin (quercetin-3-O-rutinoside) and K-grg (kaempferol-3-O-glucorhamnoglucoside) while conventional HPLC method did not. The total amounts of FOG compounds in the tea samples were 2.32-5.67g/kg dry weight (calculated as aglycones), and there is no significant difference for the total FOG content among green tea, oolong tea and black tea. However, kaempferol glycosides are more abundant in green teas, while oolong tea has more quercetin and myricetin glycosides. In black tea quercetin glycosides were most abundant.

  1. Influence of Light and Temperature on Gene Expression Leading to Accumulation of Specific Flavonol Glycosides and Hydroxycinnamic Acid Derivatives in Kale (Brassica oleracea var. sabellica).

    PubMed

    Neugart, Susanne; Krumbein, Angelika; Zrenner, Rita

    2016-01-01

    Light intensity and temperature are very important signals for the regulation of plant growth and development. Plants subjected to less favorable light or temperature conditions often respond with accumulation of secondary metabolites. Some of these metabolites have been identified as bioactive compounds, considered to exert positive effects on human health when consumed regularly. In order to test a typical range of growth parameters for the winter crop Brassica oleracea var. sabellica, plants were grown either at 400 μmol m(-2) s(-1) or 100 μmol m(-2) s(-1) at 10°C, or at 400 μmol m(-2) s(-1) with 5 or 15°C. The higher light intensity overall increased flavonol content of leaves, favoring the main quercetin glycosides, a caffeic acid monoacylated kaempferol triglycoside, and disinapoyl-gentiobiose. The higher temperature mainly increased the hydroxycinnamic acid derivative disinapoyl-gentiobiose, while at lower temperature synthesis is in favor of very complex sinapic acid acylated flavonol tetraglycosides such as kaempferol-3-O-sinapoyl-sophoroside-7-O-diglucoside. A global analysis of light and temperature dependent alterations of gene expression in B. oleracea var. sabellica leaves was performed with the most comprehensive Brassica microarray. When compared to the light experiment much less genes were differentially expressed in kale leaves grown at 5 or 15°C. A structured evaluation of differentially expressed genes revealed the expected enrichment in the functional categories of e.g. protein degradation at different light intensities or phytohormone metabolism at different temperature. Genes of the secondary metabolism namely phenylpropanoids are significantly enriched with both treatments. Thus, the genome of B. oleracea was screened for predicted genes putatively involved in the biosynthesis of flavonoids and hydroxycinnamic acid derivatives. All identified B. oleracea genes were analyzed for their most specific 60-mer oligonucleotides present on the

  2. Influence of Light and Temperature on Gene Expression Leading to Accumulation of Specific Flavonol Glycosides and Hydroxycinnamic Acid Derivatives in Kale (Brassica oleracea var. sabellica).

    PubMed

    Neugart, Susanne; Krumbein, Angelika; Zrenner, Rita

    2016-01-01

    Light intensity and temperature are very important signals for the regulation of plant growth and development. Plants subjected to less favorable light or temperature conditions often respond with accumulation of secondary metabolites. Some of these metabolites have been identified as bioactive compounds, considered to exert positive effects on human health when consumed regularly. In order to test a typical range of growth parameters for the winter crop Brassica oleracea var. sabellica, plants were grown either at 400 μmol m(-2) s(-1) or 100 μmol m(-2) s(-1) at 10°C, or at 400 μmol m(-2) s(-1) with 5 or 15°C. The higher light intensity overall increased flavonol content of leaves, favoring the main quercetin glycosides, a caffeic acid monoacylated kaempferol triglycoside, and disinapoyl-gentiobiose. The higher temperature mainly increased the hydroxycinnamic acid derivative disinapoyl-gentiobiose, while at lower temperature synthesis is in favor of very complex sinapic acid acylated flavonol tetraglycosides such as kaempferol-3-O-sinapoyl-sophoroside-7-O-diglucoside. A global analysis of light and temperature dependent alterations of gene expression in B. oleracea var. sabellica leaves was performed with the most comprehensive Brassica microarray. When compared to the light experiment much less genes were differentially expressed in kale leaves grown at 5 or 15°C. A structured evaluation of differentially expressed genes revealed the expected enrichment in the functional categories of e.g. protein degradation at different light intensities or phytohormone metabolism at different temperature. Genes of the secondary metabolism namely phenylpropanoids are significantly enriched with both treatments. Thus, the genome of B. oleracea was screened for predicted genes putatively involved in the biosynthesis of flavonoids and hydroxycinnamic acid derivatives. All identified B. oleracea genes were analyzed for their most specific 60-mer oligonucleotides present on the

  3. Influence of Light and Temperature on Gene Expression Leading to Accumulation of Specific Flavonol Glycosides and Hydroxycinnamic Acid Derivatives in Kale (Brassica oleracea var. sabellica)

    PubMed Central

    Neugart, Susanne; Krumbein, Angelika; Zrenner, Rita

    2016-01-01

    Light intensity and temperature are very important signals for the regulation of plant growth and development. Plants subjected to less favorable light or temperature conditions often respond with accumulation of secondary metabolites. Some of these metabolites have been identified as bioactive compounds, considered to exert positive effects on human health when consumed regularly. In order to test a typical range of growth parameters for the winter crop Brassica oleracea var. sabellica, plants were grown either at 400 μmol m−2 s−1 or 100 μmol m−2 s−1 at 10°C, or at 400 μmol m−2 s−1 with 5 or 15°C. The higher light intensity overall increased flavonol content of leaves, favoring the main quercetin glycosides, a caffeic acid monoacylated kaempferol triglycoside, and disinapoyl-gentiobiose. The higher temperature mainly increased the hydroxycinnamic acid derivative disinapoyl-gentiobiose, while at lower temperature synthesis is in favor of very complex sinapic acid acylated flavonol tetraglycosides such as kaempferol-3-O-sinapoyl-sophoroside-7-O-diglucoside. A global analysis of light and temperature dependent alterations of gene expression in B. oleracea var. sabellica leaves was performed with the most comprehensive Brassica microarray. When compared to the light experiment much less genes were differentially expressed in kale leaves grown at 5 or 15°C. A structured evaluation of differentially expressed genes revealed the expected enrichment in the functional categories of e.g. protein degradation at different light intensities or phytohormone metabolism at different temperature. Genes of the secondary metabolism namely phenylpropanoids are significantly enriched with both treatments. Thus, the genome of B. oleracea was screened for predicted genes putatively involved in the biosynthesis of flavonoids and hydroxycinnamic acid derivatives. All identified B. oleracea genes were analyzed for their most specific 60-mer oligonucleotides present on the

  4. Identification of complex, naturally occurring flavonoid glycosides in kale (Brassica oleracea var. sabellica) by high-performance liquid chromatography diode-array detection/electrospray ionization multi-stage mass spectrometry.

    PubMed

    Schmidt, Susanne; Zietz, Michaela; Schreiner, Monika; Rohn, Sascha; Kroh, Lothar W; Krumbein, Angelika

    2010-07-30

    Kale is a member of the Brassicaceae family and has a complex profile of flavonoid glycosides. Therefore, kale is a suitable matrix to discuss in a comprehensive study the different fragmentation patterns of flavonoid glycosides. The wide variety of glycosylation and acylation patterns determines the health-promoting effects of these glycosides. The aim of this study is to investigate the naturally occurring flavonoids in kale. A total of 71 flavonoid glycosides of quercetin, kaempferol and isorhamnetin were identified using a high-performance liquid chromatography diode-array detection/electrospray ionization multi-stage mass spectrometry (HPLC-DAD/ESI-MS(n)) method. Of these 71 flavonol glycosides, 27 were non-acylated, 30 were monoacylated and 14 were diacylated. Non-acylated flavonol glycosides were present as mono-, di-, tri- and tetraglycosides. This is the first time that the occurrence of four different fragmentation patterns of non-acylated flavonol triglycosides has been reported in one matrix simultaneously. In addition, 44 flavonol glycosides were acylated with p-coumaric, caffeic, ferulic, hydroxyferulic or sinapic acid. While monoacylated glycosides existed as di-, tri- and tetraglycosides, diacylated glycosides occurred as tetra- and pentaglycosides. To the best of our knowledge, 28 compounds in kale are reported here for the first time. These include three acylated isorhamnetin glycosides (isorhamnetin-3-O-sinapoyl-sophoroside-7-O-D-glucoside, isorhamnetin-3-O-feruloyl-sophoroside-7-O-diglucoside and isorhamnetin-3-O-disinapoyl-triglucoside-7-O-diglucoside) and seven non-acylated isorhamnetin glycosides.

  5. Inhibition of dipeptidyl peptidase activity by flavonol glycosides of guava (Psidium guajava L.): a key to the beneficial effects of guava in type II diabetes mellitus.

    PubMed

    Eidenberger, Thomas; Selg, Manuel; Krennhuber, Klaus

    2013-09-01

    Based on the traditional use in popular medicine, the effect of extracts from Psidium guajava L. leaves and of the main flavonol-glycoside components on dipeptidyl-peptidase IV (DP-IV), a key enzyme of blood glucose homoeostasis, has been investigated in-vitro. An ethanolic extract was prepared from dried, powdered leaves of guava and was found to contain seven main flavonol-glycosides, which were isolated by semipreparative HPLC and tested individually. The ethanolic guava leave extract was shown to exert a dose-dependent inhibition of DP-IV, with an IC50 of 380 μg/ml test assay solution. Also the individual flavonol-glycosides inhibited DP-IV dose-dependently, with variations of the effects by a factor of 10, and an overall effect accounting for 100% of that observed for the total guava extract. The recovery of individual flavonol-glycosides in CaCo-2 epithelial cells, a model of gastrointestinal tract absorption, amounted to 2.3-5.3% of the amount available for absorption over 60 min at 37°C. PMID:23707747

  6. UHPLC-PDA-ESI/HRMS/MSn analysis of anthocyanins, flavonol glycosides, and hydroxycinnamic acid derivatives in red mustard green (Brassica juncea (L) Coss variety)

    Technology Transfer Automated Retrieval System (TEKTRAN)

    An UHPLC-PDA-ESI/HRMS/MSn profiling method was used for a comprehensive study of the polyphenols in red mustard greens and identified 209 phenolic compounds: 67 anthocyanin, 102 flavonol glycosides, and 40 hydroxycinnamic acid derivatives. The glycosylation patterns of the flavonoids were assigned ...

  7. Inhibition of dipeptidyl peptidase activity by flavonol glycosides of guava (Psidium guajava L.): a key to the beneficial effects of guava in type II diabetes mellitus.

    PubMed

    Eidenberger, Thomas; Selg, Manuel; Krennhuber, Klaus

    2013-09-01

    Based on the traditional use in popular medicine, the effect of extracts from Psidium guajava L. leaves and of the main flavonol-glycoside components on dipeptidyl-peptidase IV (DP-IV), a key enzyme of blood glucose homoeostasis, has been investigated in-vitro. An ethanolic extract was prepared from dried, powdered leaves of guava and was found to contain seven main flavonol-glycosides, which were isolated by semipreparative HPLC and tested individually. The ethanolic guava leave extract was shown to exert a dose-dependent inhibition of DP-IV, with an IC50 of 380 μg/ml test assay solution. Also the individual flavonol-glycosides inhibited DP-IV dose-dependently, with variations of the effects by a factor of 10, and an overall effect accounting for 100% of that observed for the total guava extract. The recovery of individual flavonol-glycosides in CaCo-2 epithelial cells, a model of gastrointestinal tract absorption, amounted to 2.3-5.3% of the amount available for absorption over 60 min at 37°C.

  8. Two new flavonol glycosides and a metabolite profile of Bryophyllum pinnatum, a phytotherapeutic used in obstetrics and gynaecology.

    PubMed

    Fürer, Karin; Raith, Melanie; Brenneisen, Rudolf; Mennet, Monica; Simões-Wüst, Ana Paula; von Mandach, Ursula; Hamburger, Matthias; Potterat, Olivier

    2013-11-01

    Bryophyllum pinnatum is a succulent perennial plant native to Madagascar which is used in anthroposophical medicine to treat psychiatric disorders and as a tocolytic agent to prevent premature labour. We performed a metabolite profiling study in order to obtain a comprehensive picture of the constituents in B. pinnatum leaves and to identify chromatographic markers for quality control and safety assessment of medicinal preparations. Preliminary HPLC-PDA-ESIMS analyses revealed that flavonoid glycosides were the main UV-absorbing constituents in the MeOH extract of B. pinnatum. Two phenolic glucosides, syringic acid β-D-glucopyranosyl ester (1) and 4'-O-β-D-glucopyranosyl-cis-p-coumaric acid (2), as well as nine flavonoids (3-11) including kaempferol, quercetin, myricetin, acacetin, and diosmetin glycosides were unambiguously identified by 1H and 2D NMR analysis after isolation from a MeOH extract. The flavonol glycosides quercetin 3-O-α-L-arabinopyranosyl-(1 → 2)-α-L-rhamnopyranoside 7-O-β-D-glucopyranoside (3) and myricetin 3-O-α-L-arabinopyranosyl-(1 → 2)-α-L-rhamnopyranoside (4) were new natural products. With the aid of HPLC-PDA-APCIMS and authentic references isolated from the related species B. daigremontianum, the presence of four bufadienolides, bersaldegenin-1-acetate (12), bryophyllin A (13), bersaldegenin-3-acetate (14), and bersaldegenin-1,3,5-orthoacetate (15) was detected in B. pinnatum. PMID:24072500

  9. Natural variation in flavonol accumulation in Arabidopsis is determined by the flavonol glucosyltransferase BGLU6.

    PubMed

    Ishihara, Hirofumi; Tohge, Takayuki; Viehöver, Prisca; Fernie, Alisdair R; Weisshaar, Bernd; Stracke, Ralf

    2016-03-01

    Flavonols are colourless secondary metabolites, primarily regarded as UV-protection pigments that are deposited in plants in their glycosylated forms. The glycosylation of flavonols is mainly catalysed by UDP-sugar-dependent glycosyltransferases (UGTs). Although the structures of flavonol glycosides accumulating in Arabidopsis thaliana are known, many genes involved in the flavonol glycosylation pathway are yet to be discovered. The flavonol glycoside profiles of seedlings from 81 naturally occurring A. thaliana accessions were screened using high performance thin layer chromatography. A qualitative variation in flavonol 3-O-gentiobioside 7-O-rhamnoside (F3GG7R) content was identified. Ler × Col-0 recombinant inbred line mapping and whole genome association mapping led to the identification of a glycoside hydrolase family 1-type gene, At1g60270/BGLU6, that encodes a homolog of acyl-glucose-dependent glucosyltransferases involved in the glycosylation of anthocyanins, possibly localized in the cytoplasm, and that is co-expressed with genes linked to phenylpropanoid biosynthesis. A causal single nucleotide polymorphism introducing a premature stop codon in non-producer accessions was found to be absent in the producers. Several other naturally occurring loss-of-function alleles were also identified. Two independent bglu6 T-DNA insertion mutants from the producer accessions showed loss of F3GG7R. Furthermore, bglu6 mutant lines complemented with the genomic Ler BGLU6 gene confirmed that BGLU6 is essential for production of F3GGR7. We have thus identified an accession-specific gene that causes a qualitative difference in flavonol glycoside accumulation in A. thaliana strains. This gene encodes a flavonol 3-O-glucoside: 6″-O-glucosyltransferase that does not belong to the large canonical family of flavonol glycosyltransferases that use UDP-conjugates as the activated sugar donor substrate. PMID:26717955

  10. Natural variation in flavonol accumulation in Arabidopsis is determined by the flavonol glucosyltransferase BGLU6

    PubMed Central

    Ishihara, Hirofumi; Tohge, Takayuki; Viehöver, Prisca; Fernie, Alisdair R.; Weisshaar, Bernd; Stracke, Ralf

    2016-01-01

    Flavonols are colourless secondary metabolites, primarily regarded as UV-protection pigments that are deposited in plants in their glycosylated forms. The glycosylation of flavonols is mainly catalysed by UDP-sugar-dependent glycosyltransferases (UGTs). Although the structures of flavonol glycosides accumulating in Arabidopsis thaliana are known, many genes involved in the flavonol glycosylation pathway are yet to be discovered. The flavonol glycoside profiles of seedlings from 81 naturally occurring A. thaliana accessions were screened using high performance thin layer chromatography. A qualitative variation in flavonol 3-O-gentiobioside 7-O-rhamnoside (F3GG7R) content was identified. Ler × Col-0 recombinant inbred line mapping and whole genome association mapping led to the identification of a glycoside hydrolase family 1-type gene, At1g60270/BGLU6, that encodes a homolog of acyl-glucose-dependent glucosyltransferases involved in the glycosylation of anthocyanins, possibly localized in the cytoplasm, and that is co-expressed with genes linked to phenylpropanoid biosynthesis. A causal single nucleotide polymorphism introducing a premature stop codon in non-producer accessions was found to be absent in the producers. Several other naturally occurring loss-of-function alleles were also identified. Two independent bglu6 T-DNA insertion mutants from the producer accessions showed loss of F3GG7R. Furthermore, bglu6 mutant lines complemented with the genomic Ler BGLU6 gene confirmed that BGLU6 is essential for production of F3GGR7. We have thus identified an accession-specific gene that causes a qualitative difference in flavonol glycoside accumulation in A. thaliana strains. This gene encodes a flavonol 3-O-glucoside: 6″-O-glucosyltransferase that does not belong to the large canonical family of flavonol glycosyltransferases that use UDP-conjugates as the activated sugar donor substrate. PMID:26717955

  11. Development and Validation of an Analytical Method for the Determination of Flavonol Glycosides in Ginkgo Leaves and ShuXueNing Injections by a Single Marker.

    PubMed

    Lin, Shan; Ye, Ji; Zhang, Wei-Dong; Cao, Bang-Jing; Xu, Xi-Ke; Shan, Lei; Su, Juan

    2016-07-01

    The qualitative and quantitative analysis of the major bioactive components in traditional Chinese medicines (TCM) and their preparations is essential to evaluate their quality. However, the scarcity and high cost of chemical reference standards are common obstacles for quantitative analysis, especially for determining multicomponents. In this study, an effective and sensitive qualitative method to identify flavonol glycosides in Ginkgo leaves (Ginkgo Folium), and their preparations have been developed. Meanwhile, a simple, convenient and reproducible method for the quantitative analysis of multicomponents by a single marker (QAMS) has been established to simultaneously determine the major flavonol glycosides in Ginkgo leaves and their preparations. Among the 15 favonol glycosides that were found, 7 major flavonol glycosides with high contents were simultaneously determined by the QAMS and traditional external standard method (TES). Rutin was selected as the single marker, and the quantitative analysis was performed on a TSK gel ODS-100V C18 column using a gradient system of acetonitrile and water, with a variable wavelength detector (265 nm) within 50 min. The method validation was conducted, and the linearity was excellent (r(2) > 0.9993) with accuracy and precision within the required limits. The F-test (P> 0.05) indicated that the QAMS and TES method have no statistically significant difference. PMID:27068933

  12. Deep supercooling xylem parenchyma cells of katsura tree (Cercidiphyllum japonicum) contain flavonol glycosides exhibiting high anti-ice nucleation activity.

    PubMed

    Kasuga, Jun; Hashidoko, Yasuyuki; Nishioka, Atsushi; Yoshiba, Megumi; Arakawa, Keita; Fujikawa, Seizo

    2008-09-01

    Xylem parenchyma cells (XPCs) of boreal hardwood species adapt to sub-freezing temperatures by deep supercooling to maintain a liquid state of intracellular water near -40 degrees C. Our previous study found that crude xylem extracts from such tree species exhibited anti-ice nucleation activity to promote supercooling of water. In the present study, thus, we attempted to identify the causative substances of supercooling. Crude xylem extracts from katsura tree (Cercidiphyllum japonicum), of which XPCs exhibited deep supercooling to -40 degrees C, were prepared by methanol extraction. The crude extracts were purified by liquid-liquid extraction and then by silica gel column chromatography. Although all the fractions obtained after each purification step exhibited some levels of anti-ice nucleation activity, only the most active fraction was retained to proceed to the subsequent level of purification. High-performance liquid chromatography (HPLC) analysis of a fraction with the highest level of activity revealed four peaks with high levels of anti-ice nucleation activity in the range of 2.8-9.0 degrees C. Ultraviolet (UV), mass and nuclear magnetic resonance (NMR) spectra revealed that these four peaks corresponded to quercetin-3-O-beta-glucoside (Q3G), kaempferol-7-O-beta-glucoside (K7G), 8-methoxykaempferol-3-O-beta-glucoside (8MK3G) and kaempferol-3-O-beta-glucoside (K3G). Microscopic observations confirmed the presence of flavonoids in cytoplasms of XPCs. These results suggest that diverse kinds of anti-ice nucleation substances, including flavonol glycosides, may have important roles in deep supercooling of XPCs. PMID:18518920

  13. Deep supercooling xylem parenchyma cells of katsura tree (Cercidiphyllum japonicum) contain flavonol glycosides exhibiting high anti-ice nucleation activity.

    PubMed

    Kasuga, Jun; Hashidoko, Yasuyuki; Nishioka, Atsushi; Yoshiba, Megumi; Arakawa, Keita; Fujikawa, Seizo

    2008-09-01

    Xylem parenchyma cells (XPCs) of boreal hardwood species adapt to sub-freezing temperatures by deep supercooling to maintain a liquid state of intracellular water near -40 degrees C. Our previous study found that crude xylem extracts from such tree species exhibited anti-ice nucleation activity to promote supercooling of water. In the present study, thus, we attempted to identify the causative substances of supercooling. Crude xylem extracts from katsura tree (Cercidiphyllum japonicum), of which XPCs exhibited deep supercooling to -40 degrees C, were prepared by methanol extraction. The crude extracts were purified by liquid-liquid extraction and then by silica gel column chromatography. Although all the fractions obtained after each purification step exhibited some levels of anti-ice nucleation activity, only the most active fraction was retained to proceed to the subsequent level of purification. High-performance liquid chromatography (HPLC) analysis of a fraction with the highest level of activity revealed four peaks with high levels of anti-ice nucleation activity in the range of 2.8-9.0 degrees C. Ultraviolet (UV), mass and nuclear magnetic resonance (NMR) spectra revealed that these four peaks corresponded to quercetin-3-O-beta-glucoside (Q3G), kaempferol-7-O-beta-glucoside (K7G), 8-methoxykaempferol-3-O-beta-glucoside (8MK3G) and kaempferol-3-O-beta-glucoside (K3G). Microscopic observations confirmed the presence of flavonoids in cytoplasms of XPCs. These results suggest that diverse kinds of anti-ice nucleation substances, including flavonol glycosides, may have important roles in deep supercooling of XPCs.

  14. Interaction of moderate UV-B exposure and temperature on the formation of structurally different flavonol glycosides and hydroxycinnamic acid derivatives in kale (Brassica oleracea var. sabellica).

    PubMed

    Neugart, Susanne; Fiol, Michaela; Schreiner, Monika; Rohn, Sascha; Zrenner, Rita; Kroh, Lothar W; Krumbein, Angelika

    2014-05-01

    Kale has a high number of structurally different flavonol glycosides and hydroxycinnamic acid derivatives. In this study we investigated the interaction of moderate UV-B radiation and temperature on these compounds. Kale plants were grown at daily mean temperatures of 5 or 15 °C and were exposed to five subsequent daily doses (each 0.25 kJ m(-2) d(-1)) of moderate UV-B radiation at 1 d intervals. Of 20 phenolic compounds, 11 were influenced by an interaction of UV-B radiation and temperature, e.g., monoacylated quercetin glycosides. Concomitantly, enhanced mRNA expression of flavonol 3'- hydroxylase showed an interaction of UV-B and temperature, highest at 0.75 kJ m(-2) and 15 °C. Kaempferol glycosides responded diversely and dependent on, e.g., the hydroxycinnamic acid residue. Compounds containing a catechol structure seem to be favored in the response to UV-B. Taken together, subsequent exposure to moderate UV-B radiation is a successful tool for enhancing the flavonoid profile of plants, and temperature should be considered.

  15. Rapid Fingerprint Analysis of Plant Extracts for Ellagitannins, Gallic Acid, and Quinic Acid Derivatives and Quercetin-, Kaempferol- and Myricetin-Based Flavonol Glycosides by UPLC-QqQ-MS/MS.

    PubMed

    Engström, Marica T; Pälijärvi, Maija; Salminen, Juha-Pekka

    2015-04-29

    This paper describes the development of a rapid method with ultraperformance liquid chromatography-triple-quadrupole mass spectrometry that can specifically measure group-specific fingerprints from plant extracts for the following polyphenol groups: (1) ellagitannins, (2) gallic acid derivatives, (3) quinic acid derivatives, (4) quercetin-based flavonol glycosides, (5) kaempferol-based flavonol glycosides, and (6) myricetin-based flavonol glycosides. In addition, the method records simultaneously diode array and full scan mass spectrometry data that can be used to later characterize and quantify the main individual polyphenols if necessary. All of this is achieved within the 10 min period of analysis, which makes the presented method a significant addition to the chemistry tools currently available for the rapid analysis of complex polyphenol mixtures from plant extracts.

  16. Direct analysis of 18 flavonol glycosides, aglycones and terpene trilactones in Ginkgo biloba tablets by matrix solid phase dispersion coupled with ultra-high performance liquid chromatography tandem triple quadrupole mass spectrometry.

    PubMed

    Liu, Xin-Guang; Yang, Hua; Cheng, Xiao-Lan; Liu, Lei; Qin, Yong; Wang, Qi; Qi, Lian-Wen; Li, Ping

    2014-08-01

    Analysis and quality control of Ginkgo biloba have been comprehensively studied. However, little attention has been devoted to the simultaneous extraction and analysis of flavonols and terpene trilactones, especially for direct quantification of flavonol glycosides. This work described a rapid strategy for one-step extraction and quantification of the components. A matrix solid phase dispersion (MSPD) method was designed for the extraction of ginkgo ingredients and compared with the heat-reflux and ultrasonic extraction methods. An ultra-high performance liquid chromatography (UHPLC)-tandem-triple-quadrupole-mass spectrometry (QQQ-MS) method was developed for detection of the 18 components, including 10 original flavonol glycosides, 3 aglycones, and 5 lactones. Subsequently, the proposed strategy was used for the analysis of 12 G. biloba tablets. Results showed that MSPD produced comparable extraction efficiency but consumed less time and required lower solvent volumes compared with conventional methods. Without hydrolysis, the concentration detected was much closer to the original in the sample. The total flavonol glycoside contents in ginkgo tablets ranged from 3.59 to 125.21μgmg(-1), and the terpene trilactone varied from 3.45 to 57.8μgmg(-1) among different manufacturers. In conclusion, the proposed MSPD and UHPLC-QQQ-MS is rapid and sensitive in providing comprehensive profile of chemical constituents especially the genuine flavonol glycosides for improved quality control of ginkgo products.

  17. The simultaneous determination of selected flavonol glycosides and aglycones in Ginkgo biloba oral dosage forms by high-performance liquid chromatography-electrospray ionisation-mass spectrometry.

    PubMed

    Dubber, M-J; Sewram, V; Mshicileli, N; Shephard, G S; Kanfer, I

    2005-04-01

    An accurate, precise and sensitive liquid chromatography-tandem mass spectrometric (LC-MS-MS) method was developed for the determination of two flavonol glycosides, rutin and quercitrin, together with the algycone markers, quercetin, kaempferol and isorhamnetin in several Ginkgo biloba solid oral dosage forms. In addition, a novel quercetin glycoside, not yet reported in Ginkgo extracts, was identified. Liquid chromatography was performed using a minibore high-performance liquid chromatography (HPLC) column (150 mm x 2.0mm i.d.) and a one step gradient of acetonitrile-formic acid (0.3%) at a flow rate of 0.5 ml/min. Baseline separation of the five selected flavonol marker compounds was achieved within 20 min at 45 degrees C. Tandem mass spectrometry was performed using electrospray ionisation (ESI) in the negative ion mode. The marker compounds exhibited linearity over the range of 3-26 microg/ml and intra- and inter-day standard deviations were better than 7% and 16%, respectively. All Ginkgo products investigated were found to contain varying amounts of target analytes.

  18. Comparative characterization of total flavonol glycosides and terpene lactones at different ages, from different cultivation sources and genders of Ginkgo biloba leaves.

    PubMed

    Yao, Xin; Shang, Erxin; Zhou, Guisheng; Tang, Yuping; Guo, Sheng; Su, Shulan; Jin, Chun; Qian, Dawei; Qin, Yong; Duan, Jin-Ao

    2012-01-01

    The extract from Ginkgo biloba leaves has become a very popular plant medicine and herbal supplement for its potential benefit in alleviating symptoms associated with peripheral vascular disease, dementia, asthma and tinnitus. Most research on G. biloba leaves focus on the leaves collected in July and August from four to seven year-old trees, however a large number of leaves from fruit cultivars (trees older than 10 years) are ignored and become obsolete after fruit harvest season (November). In this paper, we expand the tree age range (from one to 300 years) and first comparatively analyze the total flavonol glycosides and terpene lactones at different ages, from different cultivation sources and genders of G. biloba leaves collected in November by using the validated HPLC-ELSD and HPLC-PDA methods. The results show that the contents of total terpene lactones and flavonol glycosides in the leaves of young ginkgo trees are higher than those in old trees, and they are higher in male trees than in female trees. Geographical factors appear to have a significant influence on the contents as well. These results will provide a good basis for the comprehensive utilization of G. biloba leaves, especially the leaves from fruit cultivars.

  19. Computer-aided method for identification of major flavone/flavonol glycosides by high-performance liquid chromatography-diode array detection-tandem mass spectrometry (HPLC-DAD-MS/MS).

    PubMed

    Wang, Zhengfang; Lin, Longze; Harnly, James M; Harrington, Peter de B; Chen, Pei

    2014-11-01

    A new computational tool is proposed here for tentatively identifying major (UV quantifiable) flavone/flavonol glycoside peaks of high performance liquid chromatogram (HPLC)-diode array detection (DAD)-tandem mass spectrometry (MS/MS) profiles based on a MATLAB-based script implementing an in-house algorithm. The HPLC-DAD-MS/MS profiles of red onion, Chinese lettuce, carrot leaf, and celery seed extracts were analyzed by the proposed computer-aided screening method for identifying possible flavone/flavonol glycoside peaks from the HPLC-UV and MS total ion current (TIC) chromatograms. The number of identified flavone/flavonol glycoside peaks of the HPLC-UV chromatograms is four, four, six, and nine for red onion, Chinese lettuce, carrot leaf, and celery seed, respectively. These results have been validated by human(s) experts. For the batch processing of nine HPLC-DAD-MS/MS profiles of celery seed extract, the entire script execution time was within 15 s while manual calculation of only one HPLC-DAD-MS/MS profile by a flavonoid expert could take hours. Therefore, this MATLAB-based screening method is able to facilitate the HPLC-DAD-MS/MS analysis of flavone/flavonol glycosides in plants to a large extent.

  20. Computer-aided method for identification of major flavone/flavonol glycosides by high-performance liquid chromatography-diode array detection-tandem mass spectrometry (HPLC-DAD-MS/MS).

    PubMed

    Wang, Zhengfang; Lin, Longze; Harnly, James M; Harrington, Peter de B; Chen, Pei

    2014-11-01

    A new computational tool is proposed here for tentatively identifying major (UV quantifiable) flavone/flavonol glycoside peaks of high performance liquid chromatogram (HPLC)-diode array detection (DAD)-tandem mass spectrometry (MS/MS) profiles based on a MATLAB-based script implementing an in-house algorithm. The HPLC-DAD-MS/MS profiles of red onion, Chinese lettuce, carrot leaf, and celery seed extracts were analyzed by the proposed computer-aided screening method for identifying possible flavone/flavonol glycoside peaks from the HPLC-UV and MS total ion current (TIC) chromatograms. The number of identified flavone/flavonol glycoside peaks of the HPLC-UV chromatograms is four, four, six, and nine for red onion, Chinese lettuce, carrot leaf, and celery seed, respectively. These results have been validated by human(s) experts. For the batch processing of nine HPLC-DAD-MS/MS profiles of celery seed extract, the entire script execution time was within 15 s while manual calculation of only one HPLC-DAD-MS/MS profile by a flavonoid expert could take hours. Therefore, this MATLAB-based screening method is able to facilitate the HPLC-DAD-MS/MS analysis of flavone/flavonol glycosides in plants to a large extent. PMID:25270867

  1. Flavonol glycosides with lipid accumulation inhibitory activity and simultaneous quantitative analysis of 15 polyphenols and caffeine in the flower buds of Camellia sinensis from different regions by LCMS.

    PubMed

    Morikawa, Toshio; Ninomiya, Kiyofumi; Miyake, Sohachiro; Miki, Yoshinobu; Okamoto, Masaki; Yoshikawa, Masayuki; Muraoka, Osamu

    2013-09-01

    A simultaneous quantitative analytical method for 15 major polyphenols, e.g. five catechins (1-5) and 10 flavonols (6-15), as functional constituents in the extracts of "tea flowers", the flower buds of Camellia sinensis (Theaceae), has been developed. The content of caffeine (16), which showed similar chromatographic behaviour under the analytical conditions, was also determined. To approve the validity of the newly developed protocol, thirteen extracts of the plant's flower buds collected from different regions, i.e. China, Taiwan, Japan and India, were evaluated. The results indicated that the assay was reproducible and precise, and could be readily underutilised for the quality evaluation of tea flowers on the basis of polyphenols' contents. It was noteworthy that the contents of two major constituents, kaempferol 3-O-β-D-glucopyranosyl-(1→3)-α-L-rhamnopyranosyl-(1→6)-β-D-glucopyranoside (10) and kaempferol 3-O-β-D-glucopyranosyl-(1→3)-α-L-rhamnopyranosyl-(1→6)-β-D-galactopyranoside (11), varied by region where the flower buds were produced. A new flavonol glycoside, chakaflavonoside B (17), which was isolated in the course of this analytical study, was found to show oleic acid-albumin-induced lipid accumulation inhibitory activity.

  2. Immunomodulatory N-acyl Dopamine Glycosides from the Icelandic Marine Sponge Myxilla incrustans Collected at a Hydrothermal Vent Site.

    PubMed

    Einarsdottir, Eydis; Liu, Hong-Bing; Freysdottir, Jona; Gotfredsen, Charlotte Held; Omarsdottir, Sesselja

    2016-06-01

    A chemical investigation of the sponge (Porifera) Myxilla incrustans collected from the unique submarine hydrothermal vent site Strytan, North of Iceland, revealed a novel family of closely related N-acyl dopamine glycosides. Three new compounds, myxillin A (1), B (2) and C (3), were isolated and structurally elucidated using several analytical techniques, such as HR-MS, 1D and 2D NMR spectroscopy. Myxillin A (1) and B (2)were shown to be structurally similar, composed of a dopamine moiety, but differ in the acyl chain length and saturation. The myxillin C (3) has a dehydrotyrosine moiety composing the same acyl chain and glycosylation as myxillin B (2). Myxillins A (1) and C (3) were tested for immunomodulating activity in an in vitro dendritic cell model. Dendritic cells matured and stimulated in the presence of myxillin A (1) secreted lower levels of IL-12p40, whilst dendritic cells matured and stimulated in the presence of myxillin C (3) secreted lower levels of IL-10 compared with dendritic cells matured and stimulated in the presence of the solvent alone. These opposing results indicate that the structural differences in the aromatic ring part of the molecules could have an impact on the immunological effects of dendritic cells. These molecules could, therefore, prove to be important in preventing inflammatory diseases on the one hand, and inducing a response to fight tumors and/or pathogens on the other hand. Further studies will be needed to confirm these potential uses. PMID:27135626

  3. In silico discovery of acylated flavonol monorhamnosides from Eriobotrya japonica as natural, small-molecular weight inhibitors of XIAP BIR3.

    PubMed

    Pfisterer, Petra H; Shen, Chenxi; Nikolovska-Coleska, Zaneta; Schyschka, Lilianna; Schuster, Daniela; Rudy, Anita; Wolber, Gerhard; Vollmar, Angelika M; Rollinger, Judith M; Stuppner, Hermann

    2011-01-15

    Targeting the baculoviral inhibitor of apoptosis proteins repeat (BIR) 3 of X-linked inhibitor of apoptosis proteins (XIAP) represents an innovative strategy for the design of chemosensitizers. Acylated flavonol monorhamnosides (AFMR) from Eriobotrya japonica Lindl. (Rosaceae) were virtually predicted as ligands of the XIAP BIR3 domain by using a previously generated pharmacophore model. From the methanol leaf extract of E. japonica an enriched mixture of AFMR was obtained showing chemosensitizing potential in combination with etoposide in XIAP-overexpressing Jurkat cells. The HPLC-SPE-NMR hyphenated technique facilitated the structure elucidation of three known and two new natural AFMR. The main constituent and virtual hit, kaempferol-3-O-α-l-(2″,4″-di-E-p-coumaroyl)-rhamnoside (3) was isolated from the enriched fraction. Applying a fluorescence polarization based binding assay, 3 was identified as XIAP BIR3 ligand with a dose-dependent affinity (IC₅₀ 10.4 μM). Further, 3 induced apoptosis in XIAP-overexpressing Jurkat cells and activated caspase-9 in combination with etoposide. Docking experiments revealed a major impact of the coumaric acid and sugar moieties of 3 on XIAP BIR3 binding, which was experimentally confirmed. To conclude, this study elucidates 3 as natural, small-molecular weight XIAP BIR3 inhibitor using a combination of in silico and HPLC-SPE-NMR hyphenated techniques.

  4. Quantitative Analysis and Comparison of Four Major Flavonol Glycosides in the Leaves of Toona sinensis (A. Juss.) Roemer (Chinese Toon) from Various Origins by High-Performance Liquid Chromatography-Diode Array Detector and Hierarchical Clustering Analysis

    PubMed Central

    Sun, Xiaoxiang; Zhang, Liting; Cao, Yaqi; Gu, Qinying; Yang, Huan; Tam, James P.

    2016-01-01

    Background: Toona sinensis (A. Juss.) Roemer is an endemic species of Toona genus native to Asian area. Its dried leaves are applied in the treatment of many diseases; however, few investigations have been reported for the quantitative analysis and comparison of major bioactive flavonol glycosides in the leaves harvested from various origins. Objective: To quantitatively analyze four major flavonol glycosides including rutinoside, quercetin-3-O-β-D-glucoside, quercetin-3-O-α-L-rhamnoside, and kaempferol-3-O-α-L-rhamnoside in the leaves from different production sites and classify them according to the content of these glycosides. Materials and Methods: A high-performance liquid chromatography-diode array detector (HPLC-DAD) method for their simultaneous determination was developed and validated for linearity, precision, accuracy, stability, and repeatability. Moreover, the method established was then employed to explore the difference in the content of these four glycosides in raw materials. Finally, a hierarchical clustering analysis was performed to classify 11 voucher specimens. Results: The separation was performed on a Waters XBridge Shield RP18 column (150 mm × 4.6 mm, 3.5 μm) kept at 35°C, and acetonitrile and H2O containing 0.30% trifluoroacetic acid as mobile phase was driven at 1.0 mL/min during the analysis. Ten microliters of solution were injected and 254 nm was selected to monitor the separation. A strong linear relationship between the peak area and concentration of four analytes was observed. And, the method was also validated to be repeatable, stable, precise, and accurate. Conclusion: An efficient and reliable HPLC-DAD method was established and applied in the assays for the samples from 11 origins successfully. Moreover, the content of those flavonol glycosides varied much among different batches, and the flavonoids could be considered as biomarkers to control the quality of Chinese Toon. SUMMARY Four major flavonol glycosides in the leaves

  5. Biosynthesis of malonylated flavonoid glycosides on the basis of malonyltransferase activity in the petals of Clitoria ternatea.

    PubMed

    Kogawa, Koichiro; Kazuma, Kohei; Kato, Naoki; Noda, Naonobu; Suzuki, Masahiko

    2007-07-01

    The crude malonyltransferase from the petals of Clitoria ternatea was characterized enzymatically to investigate its role on the biosynthetic pathways of anthocyanins and flavonol glycosides. In C. ternatea, a blue flower cultivars (DB) and mauve flower variety (WM) accumulate polyacylated anthocyanins (ternatins) and delphinidin 3-O-(6''-O-malonyl)-beta-glucoside which is one of the precursors of ternatins, respectively. Moreover, WM accumulates minor delphinidin glycosides - 3-O-beta-glucoside, 3-O-(2''-O-alpha-rhamnosyl)-beta-glucoside, 3-O-(2''-O-alpha-rhamnosyl-6''-O-malonyl)-beta-glucoside of delphinidin. These glycosidic patterns for minor anthocyanins in WM are also found among the minor flavonol glycosides in all the varieties including a white flower variety (WW) although the major flavonol glycosides are 3-O-(2''-O-alpha-rhamnosyl)-beta-glucoside, 3-O-(6''-O-alpha-rhamnosyl)-beta-glucoside, 3-O-(2'',6''-di-O-alpha-rhamnosyl)-beta-glucoside of kaempferol, quercetin, and myricetin. How do the enzymatic characteristics affect the variety of glycosidic patterns in the flavonoid glycoside biosynthesis among these varieties? While the enzyme from DB highly preferred delphinidin 3-O-beta-glucoside in the presence of malonyl-CoA, it also has a preference for other anthocyanidin 3-O-beta-glucosides. It could use flavonol 3-O-beta-glucosides in much lower specific activities than anthocyanins; however, it could not utilize 3-O-(2''-O-alpha-rhamnosyl)-beta-glucosides of anthocyanins and flavonols, and 3,3'-di- and 3,3',5'-tri-O-beta-glucoside of delphinidin - other possible precursors in ternatins biosynthesis. It highly preferred malonyl-CoA as an acyl donor in the presence of delphinidin 3-O-beta-glucoside. The crude enzymes prepared from WM and WW had the same enzymatic characteristics. These results suggested that 3-O-(2''-O-alpha-rhamnosyl-6''-O-malonyl)-beta-glucosides of flavonoids were synthesized via 3-O-(6''-O-malonyl)-beta-glucosides rather than via 3-O

  6. β-Hydroxydihydrochalcone and flavonoid glycosides along with triterpene saponin and sesquiterpene from the herbs of Pimpinella rhodantha Boiss.

    PubMed

    Özbek, Hilal; Güvenalp, Zühal; Kuruüzüm-Uz, Ay E; Kazaz, Cavit; Demirezer, L Ömür

    2016-01-01

    A new β-hydroxydihydrochalcone glycoside named ziganin (1) and a new acylated flavonol glycoside named isorhamnetin-3-O-α-L-(2″,3″-di-O-trans-coumaroyl)-rhamnopyranoside) (2), along with two known flavonoid glycosides, a β-hydroxydihydrochalcone glycoside, a hydroxybenzoic acid derivative, a trinorguaiane type sesquiterpenoid, a triterpenic saponin and a polyol were isolated from the herbs of Pimpinella rhodantha Boiss. Their structures were elucidated on the basis of spectroscopic analyses including 1D-and 2D-NMR, UV, IR, CD, ESI-MS, APCI-MS, HR-ESI-MS techniques. The isolated compounds were evaluated for their antioxidant capacity through the DPPH free-radical scavenging assay and ferrous ion-chelating power test. PMID:26207840

  7. Simultaneous Quantification of Flavonol Glycosides, Terpene Lactones, Biflavones, Proanthocyanidins, and Ginkgolic Acids in Ginkgo biloba Leaves from Fruit Cultivars by Ultrahigh-Performance Liquid Chromatography Coupled with Triple Quadrupole Mass Spectrometry

    PubMed Central

    Yao, Xin; Zhou, Gui-Sheng; Tang, Yu-Ping; Qian, Ye-Fei; Guan, Han-Liang; Pang, Hanqing; Zhu, Shaoqing; Mo, Xuan; Su, Shu-Lan; Jin, Chun; Qin, Yong; Qian, Da-Wei; Duan, Jin-Ao

    2013-01-01

    On the basis of liquid chromatography coupled with triple quadrupole mass spectrometry working in multiple reaction monitoring mode, an analytical method has been established to simultaneously determine flavonol glycosides, terpene lactones, biflavones, proanthocyanidins, and ginkgolic acids in Ginkgo biloba leaves. Chromatographic separation was carried out on an Acquity BEH C18 column (100 mm × 2.1 mm, 1.7 μm) with gradient elution of acetonitrile and 0.10% formic acid (v/v) at a flow rate of 0.4 mL/min, and column temperature 30°C. The developed method was validated in terms of linearity, accuracy, precision, stability, and sensitivity. The optimized method was successfully applied to analyze twenty-two G. biloba leaf samples of fruit cultivars collected from different places in China. Furthermore, hierarchical clustering analysis (HCA) was performed to evaluate and classify the samples according to the contents of the twenty-four chemical constituents. All of the results demonstrated that the developed method was useful for the overall evaluation of the quality of G. biloba leaves, and this study was also helpful for the comprehensive utilization and development of G. biloba resources. PMID:23533996

  8. Simultaneous quantification of flavonol glycosides, terpene lactones, biflavones, proanthocyanidins, and ginkgolic acids in Ginkgo biloba leaves from fruit cultivars by ultrahigh-performance liquid chromatography coupled with triple quadrupole mass spectrometry.

    PubMed

    Yao, Xin; Zhou, Gui-Sheng; Tang, Yu-Ping; Qian, Ye-Fei; Guan, Han-Liang; Pang, Hanqing; Zhu, Shaoqing; Mo, Xuan; Su, Shu-Lan; Jin, Chun; Qin, Yong; Qian, Da-Wei; Duan, Jin-Ao

    2013-01-01

    On the basis of liquid chromatography coupled with triple quadrupole mass spectrometry working in multiple reaction monitoring mode, an analytical method has been established to simultaneously determine flavonol glycosides, terpene lactones, biflavones, proanthocyanidins, and ginkgolic acids in Ginkgo biloba leaves. Chromatographic separation was carried out on an Acquity BEH C18 column (100 mm × 2.1 mm, 1.7  μ m) with gradient elution of acetonitrile and 0.10% formic acid (v/v) at a flow rate of 0.4 mL/min, and column temperature 30°C. The developed method was validated in terms of linearity, accuracy, precision, stability, and sensitivity. The optimized method was successfully applied to analyze twenty-two G. biloba leaf samples of fruit cultivars collected from different places in China. Furthermore, hierarchical clustering analysis (HCA) was performed to evaluate and classify the samples according to the contents of the twenty-four chemical constituents. All of the results demonstrated that the developed method was useful for the overall evaluation of the quality of G. biloba leaves, and this study was also helpful for the comprehensive utilization and development of G. biloba resources.

  9. Ultra performance liquid chromatography-tandem quadrupole mass spectrometry profiling of anthocyanins and flavonols in cowpea (Vigna unguiculata) of varying genotypes.

    PubMed

    Ojwang, Leonnard O; Dykes, Linda; Awika, Joseph M

    2012-04-11

    The structure of flavonoids in food plants affects bioactivity and important nutritional attributes, like micronutrient bioavailability. This study investigated flavonol and anthocyanin compositions of cowpea (Vigna unguiculata) of varying genotypes. Black, red, green, white, light brown, and golden brown cowpea phenotypes were analyzed for anthocyanins and flavonols using ultra performance liquid chromatography-tandem quadrupole mass spectrometry. Eight anthocyanins and 23 flavonols (15 newly identified in cowpea) were characterized. Mono-, di-, and tri(acyl)glycosides of quercetin were predominant in most phenotypes; myricetin and kaempferol glycosides were present only in specific phenotypes. The red phenotypes had the highest flavonol content (880-1060 μg/g), whereas green and white phenotypes had the lowest (270-350 μg/g). Only black (1676-2094 μg/g) and green (875 μg/g) phenotypes had anthocyanins, predominantly delphinidin and cyanidin 3-O-glucosides. Cowpea phenotype influenced the type and amount of flavonoids accumulated in the seed; this may have implications in selecting varieties for nutrition and health applications.

  10. Mass-spectrometric structure elucidation of dog bile azopigments as the acyl glycosides of glucopyranose and xylopyranose

    PubMed Central

    Compernolle, F.; Van Hees, G. P.; Fevery, J.; Heirwegh, K. P. M.

    1971-01-01

    1. The structures of the α2- and α3-azopigments, prepared by diazotization of dog bile with ethyl anthranilate, were shown by mass spectrometry and g.l.c. to correspond to azobilirubin β-d-xylopyranoside and azobilirubin β-d-glucopyranoside respectively. 2. Both azopigments consist of a mixture of two methyl vinyl isomers having structures (IIIa) and (IIIb) for the α2-azopigment and structures (IVa) and (IVb) for the α3-azopigment. Separation of methyl vinyl isomers was obtained by t.l.c. or column chromatography performed on the acetylated azopigments. Hydrolysis of the less polar acetates derived from components (IIIa) and (IVa) gave rise to the azopigment (Ia), whereas hydrolysis of the more polar acetates derived from components (IIIb) and (IVb) gave rise to the azopigment acid (Ib). The positions of methyl and vinyl substituents in compounds (Ia) and (Ib) were assigned on the basis of their n.m.r. spectra. 3. Molecular ions in the mass spectra of the trimethylsilyl and acetyl derivatives of the azopigments indicated the presence of a pentose and a hexose conjugating sugar. 4. The ester functions linking the sugars to the propionic acid side chain of azobilirubin were demonstrated by ammonolysis and identification of the amide of azobilirubin as the aglycone derivative. 5. The sugar moieties were shown to occur as xylopyranose (α2) and glucopyranose (α3), bound at C-1, by application of a sequence of reactions performed on a micro-scale. The sugar hydroxyl groups were acetylated and the 1-acyl aglycone removed selectively by treatment with hydrogen bromide in acetic acid. Hydrolysis of the 1-bromo sugar acetates followed by acetylation afforded the α- and β-xylopyranose tetra-acetates and α- and β-glucopyranose penta-acetates, identified by a combination of g.l.c. and mass spectrometry. 6. The validity of this degradation scheme was confirmed (a) by g.l.c.–mass spectrometry identification of the α- and β-1-propionyl derivatives of glucopyranose

  11. Covalent anthocyanin-flavonol complexes from the violet-blue flowers of Allium 'Blue Perfume'.

    PubMed

    Saito, Norio; Nakamura, Maiko; Shinoda, Koichi; Murata, Naho; Kanazawa, Toshinari; Kato, Kazuhisa; Toki, Kenjiro; Kasai, Hiroko; Honda, Toshio; Tatsuzawa, Fumi

    2012-08-01

    Three covalent anthocyanin-flavonol complexes (pigments 1-3) were extracted from the violet-blue flower of Allium 'Blue Perfume' with 5% acetic acid-MeOH solution, in which pigment 1 was the dominant pigment. These three pigments are based on delphinidin 3-glucoside as their deacylanthocyanin and were acylated with malonyl kaempferol 3-sophoroside-7-glucosiduronic acid or malonyl-kaempferol 3-p-coumaroyl-tetraglycoside-7-glucosiduronic acid in addition to acylation with acetic acid. By spectroscopic and chemical methods, the structures of these three pigments 1-3 were determined to be: pigment 1, (6(I)-O-(delphinidin 3-O-(3(I)-O-(acetyl)-β-glucopyranoside(I))))(2(VI)-O-(kaempferol 3-O-(2(II)-O-(3(III)-O-(β-glucopyranosyl(V))-β-glucopyranosyl(III))-4(II)-O-(trans-p-coumaroyl)-6(II)-O-(β-glucopyranosyl(IV))-β-glucopyranoside(II))-7-O-(β-glucosiduronic acid(VI)))) malonate; pigment 2, (6(I)-O-(delphinidin 3-O-(3(I)-O-(acetyl)-β-glucopyranoside(I))))(2(VI)-O-(kaempferol 3-O-(2(II)-O-β-glucopyranosyl(III))-β-glucopyranoside(II))-7-O-(β-glucosiduronic acid(VI)))); and pigment 3, (6(I)-O-(delphinidin 3-O-(3(I)-O-(acetyl)-β-glucopyranoside(I))))(2(VI)-O-(kaempferol 3-O-(2(II)-O-(3(III)-O-(β-glucopyranosyl(V))-β-glucopyranosyl(III))-4(II)-O-(cis-p-coumaroyl)-6(II)-O-(β-glucopyranosyl(IV))-β-glucopyranoside(II))-7-O-(β-glucosiduronic acid(VI)))) malonate. The structure of pigment 2 was analogous to that of a covalent anthocyanin-flavonol complex isolated from Allium schoenoprasum where delphinidin was observed in place of cyanidin. The three covalent anthocyanin-flavonol complexes (pigment 1-3) had a stable violet-blue color with three characteristic absorption maxima at 540, 547 and 618nm in pH 5-6 buffer solution. From circular dichroism measurement of pigment 1 in the pH 6.0 buffer solution, cotton effects were observed at 533 (+), 604 (-) and 638 (-) nm. Based on these results, these covalent anthocyanin-flavonol complexes were presumed to maintain a

  12. Characterization of flavonols in cranberry (Vaccinium macrocarpon) powder.

    PubMed

    Vvedenskaya, Irina O; Rosen, Robert T; Guido, Jane E; Russell, David J; Mills, Kent A; Vorsa, Nicholi

    2004-01-28

    Flavonoids were extracted from cranberry powder with acetone and ethyl acetate and subsequently fractionated with Sephadex LH-20 column chromatography. The fraction eluted with a 60% methanol solution was composed primarily of phenolic constituents with maximum absorbance at 340 nm. A high-performance liquid chromatography procedure was developed, which resolved 22 distinct peaks with UV/vis and mass spectra corresponding to flavonol glycoside conjugates. Six new constituents not previously reported in cranberry or in cranberry products were determined through NMR spectroscopy to be myricetin-3-beta-xylopyranoside, quercetin-3-beta-glucoside, quercetin-3-alpha-arabinopyranoside, 3'-methoxyquercetin-3-alpha-xylopyranoside, quercetin-3-O-(6' '-p-coumaroyl)-beta-galactoside, and quercetin-3-O-(6' '-benzoyl)-beta-galactoside. Quercetin-3-O-(6' '-p-coumaroyl)-beta-galactoside and quercetin-3-O-(6' '-benzoyl)-beta-galactoside represent a new class of cranberry flavonol compounds with three conjugated components consisting of a flavonol, sugar, and carboxylic acid (benzoic or hydroxycinnamic acids). This is also the first report identifying quercetin-3-arabinoside in both furanose and pyranose forms in cranberry. Elucidation of specific flavonol glycosides in cranberry is significant since the specificity of the sugar moiety may play a role in the bioavailability of the flavonol glycosides in vivo.

  13. 7-Rhamnosylated Flavonols Modulate Homeostasis of the Plant Hormone Auxin and Affect Plant Development.

    PubMed

    Kuhn, Benjamin M; Errafi, Sanae; Bucher, Rahel; Dobrev, Petre; Geisler, Markus; Bigler, Laurent; Zažímalová, Eva; Ringli, Christoph

    2016-03-01

    Flavonols are a group of secondary metabolites that affect diverse cellular processes. They are considered putative negative regulators of the transport of the phytohormone auxin, by which they influence auxin distribution and concomitantly take part in the control of plant organ development. Flavonols are accumulating in a large number of glycosidic forms. Whether these have distinct functions and diverse cellular targets is not well understood. The rol1-2 mutant of Arabidopsis thaliana is characterized by a modified flavonol glycosylation profile that is inducing changes in auxin transport and growth defects in shoot tissues. To determine whether specific flavonol glycosides are responsible for these phenotypes, a suppressor screen was performed on the rol1-2 mutant, resulting in the identification of an allelic series of UGT89C1, a gene encoding a flavonol 7-O-rhamnosyltransferase. A detailed analysis revealed that interfering with flavonol rhamnosylation increases the concentration of auxin precursors and auxin metabolites, whereas auxin transport is not affected. This finding provides an additional level of complexity to the possible ways by which flavonols influence auxin distribution and suggests that flavonol glycosides play an important role in regulating plant development.

  14. Identification of acylated xanthone glycosides by liquid chromatography-atmospheric pressure chemical ionization mass spectrometry in positive and negative modes from the lichen Umbilicaria proboscidea.

    PubMed

    Rezanka, Tomás; Dembitsky, Valery M

    2003-05-01

    The xanthoside composition of the crude extract of Umbilicaria proboscidea (L.) Schrader was characterized using LC-UV diode array detection and LC-atmospheric pressure chemical ionization (APCI) MS methods. The presence of acylated xanthone-O-glucosides was determined by both positive and negative ion LC-APCI-MS methods. Based on UV and MS spectral data and NMR spectroscopy, a total of 14 compounds (6-O-acylated umbilicaxanthosides A and B) were identified in U. proboscidea for the first time. In order to further develop the applicability of LC-MS techniques in phytochemical characterization, the effect of different ionization energy on fragmentation was studied using APCI. The optimal ionization conditions were achieved in positive ion APCI by using ammonium acetate buffer and in negative ion APCI by using formic acid (pH 4).

  15. Genetic Variation of Flavonols Quercetin, Myricetin, and Kaempferol in the Sri Lankan Tea (Camellia sinensis L.) and Their Health-Promoting Aspects.

    PubMed

    Jeganathan, Brasathe; Punyasiri, P A Nimal; Kottawa-Arachchi, J Dananjaya; Ranatunga, Mahasen A B; Abeysinghe, I Sarath B; Gunasekare, M T Kumudini; Bandara, B M Ratnayake

    2016-01-01

    Flavonol glycosides in tea leaves have been quantified as aglycones, quercetin, myricetin, and kaempferol. Occurrence of the said compounds was reported in fruits and vegetable for a long time in association with the antioxidant potential. However, data on flavonols in tea were scanty and, hence, this study aims to envisage the flavonol content in a representative pool of accessions present in the Sri Lankan tea germplasm. Significant amounts of myricetin, quercetin, and kaempferol have been detected in the beverage type tea accessions of the Sri Lankan tea germplasm. This study also revealed that tea is a good source of flavonol glycosides. The Camellia sinensis var. sinensis showed higher content of myricetin, quercetin, and total flavonols than var. assamica and ssp. lasiocalyx. Therefore flavonols and their glycosides can potentially be used in chemotaxonomic studies of tea germplasm. The nonbeverage type cultivars, especially Camellia rosaflora and Camellia japonica Red along with the exotic accessions resembling China type, could be useful in future germplasm studies because they are rich sources of flavonols, namely, quercetin and kaempferol, which are potent antioxidants. The flavonol profiles can be effectively used in choosing parents in tea breeding programmes to generate progenies with a wide range of flavonol glycosides.

  16. Genetic Variation of Flavonols Quercetin, Myricetin, and Kaempferol in the Sri Lankan Tea (Camellia sinensis L.) and Their Health-Promoting Aspects

    PubMed Central

    Jeganathan, Brasathe; Kottawa-Arachchi, J. Dananjaya; Ranatunga, Mahasen A. B.; Abeysinghe, I. Sarath B.; Gunasekare, M. T. Kumudini; Bandara, B. M. Ratnayake

    2016-01-01

    Flavonol glycosides in tea leaves have been quantified as aglycones, quercetin, myricetin, and kaempferol. Occurrence of the said compounds was reported in fruits and vegetable for a long time in association with the antioxidant potential. However, data on flavonols in tea were scanty and, hence, this study aims to envisage the flavonol content in a representative pool of accessions present in the Sri Lankan tea germplasm. Significant amounts of myricetin, quercetin, and kaempferol have been detected in the beverage type tea accessions of the Sri Lankan tea germplasm. This study also revealed that tea is a good source of flavonol glycosides. The Camellia sinensis var. sinensis showed higher content of myricetin, quercetin, and total flavonols than var. assamica and ssp. lasiocalyx. Therefore flavonols and their glycosides can potentially be used in chemotaxonomic studies of tea germplasm. The nonbeverage type cultivars, especially Camellia rosaflora and Camellia japonica Red along with the exotic accessions resembling China type, could be useful in future germplasm studies because they are rich sources of flavonols, namely, quercetin and kaempferol, which are potent antioxidants. The flavonol profiles can be effectively used in choosing parents in tea breeding programmes to generate progenies with a wide range of flavonol glycosides. PMID:27366737

  17. Overexpression of petunia chalcone isomerase in tomato results in fruit containing increased levels of flavonols.

    PubMed

    Muir, S R; Collins, G J; Robinson, S; Hughes, S; Bovy, A; Ric De Vos, C H; van Tunen, A J; Verhoeyen, M E

    2001-05-01

    Tomatoes are an excellent source of the carotenoid lycopene, a compound that is thought to be protective against prostate cancer. They also contain small amounts of flavonoids in their peel ( approximately 5-10 mg/kg fresh weight), mainly naringenin chalcone and the flavonol rutin, a quercetin glycoside. Flavonols are very potent antioxidants, and an increasing body of epidemiological data suggests that high flavonoid intake is correlated with a decreased risk for cardiovascular disease. We have upregulated flavonol biosynthesis in the tomato in order to generate fruit with increased antioxidant capacity and a wider range of potential health benefit properties. This involved transformation of tomato with the Petunia chi-a gene encoding chalcone isomerase. Resulting transgenic tomato lines produced an increase of up to 78 fold in fruit peel flavonols, mainly due to an accumulation of rutin. No gross phenotypical differences were observed between high-flavonol transgenic and control lines. The phenotype segregated with the transgene and demonstrated a stable inheritance pattern over four subsequent generations tested thus far. Whole-fruit flavonol levels in the best of these lines are similar to those found in onions, a crop with naturally high levels of flavonol compounds. Processing of high-flavonol tomatoes demonstrated that 65% of flavonols present in the fresh fruit were retained in the processed paste, supporting their potential as raw materials for tomato-based functional food products. PMID:11329019

  18. Overexpression of petunia chalcone isomerase in tomato results in fruit containing increased levels of flavonols.

    PubMed

    Muir, S R; Collins, G J; Robinson, S; Hughes, S; Bovy, A; Ric De Vos, C H; van Tunen, A J; Verhoeyen, M E

    2001-05-01

    Tomatoes are an excellent source of the carotenoid lycopene, a compound that is thought to be protective against prostate cancer. They also contain small amounts of flavonoids in their peel ( approximately 5-10 mg/kg fresh weight), mainly naringenin chalcone and the flavonol rutin, a quercetin glycoside. Flavonols are very potent antioxidants, and an increasing body of epidemiological data suggests that high flavonoid intake is correlated with a decreased risk for cardiovascular disease. We have upregulated flavonol biosynthesis in the tomato in order to generate fruit with increased antioxidant capacity and a wider range of potential health benefit properties. This involved transformation of tomato with the Petunia chi-a gene encoding chalcone isomerase. Resulting transgenic tomato lines produced an increase of up to 78 fold in fruit peel flavonols, mainly due to an accumulation of rutin. No gross phenotypical differences were observed between high-flavonol transgenic and control lines. The phenotype segregated with the transgene and demonstrated a stable inheritance pattern over four subsequent generations tested thus far. Whole-fruit flavonol levels in the best of these lines are similar to those found in onions, a crop with naturally high levels of flavonol compounds. Processing of high-flavonol tomatoes demonstrated that 65% of flavonols present in the fresh fruit were retained in the processed paste, supporting their potential as raw materials for tomato-based functional food products.

  19. Quercetin: A flavonol with multifaceted therapeutic applications?

    PubMed

    D'Andrea, Gabriele

    2015-10-01

    Great interest is currently centered on the biologic activities of quercetin a polyphenol belonging to the class of flavonoids, natural products well known for their beneficial effects on health, long before their biochemical characterization. In particular, quercetin is categorized as a flavonol, one of the five subclasses of flavonoid compounds. Although flavonoids occur as either glycosides (with attached glycosyl groups) or as aglycones, most altogether of the dietary intake concerning quercetin is in the glycoside form. Following chewing, digestion, and absorption sugar moieties can be released from quercetin glycosides. Several organs contribute to quercetin metabolism, including the small intestine, the kidneys, the large intestine, and the liver, giving rise to glucuronidated, methylated, and sulfated forms of quercetin; moreover, free quercetin (such as aglycone) is also found in plasma. Quercetin is now largely utilized as a nutritional supplement and as a phytochemical remedy for a variety of diseases like diabetes/obesity and circulatory dysfunction, including inflammation as well as mood disorders. Owing to its basic chemical structure themost obvious feature of quercetin is its strong antioxidant activity which potentially enables it to quench free radicals from forming resonance-stabilized phenoxyl radicals. In this review the molecular, cellular, and functional bases of therapy will be emphasized taking strictly into account data appearing in the peer-reviewed literature and summarizing the main therapeutic applications of quercetin; furthermore, the drug metabolism and the main drug interaction as well as the potential toxicity will be also spotlighted.

  20. Five new resin glycoside derivatives isolated from the convolvulin fraction of seeds of Quamoclit pennata after treatment with indium(III) chloride in methanol.

    PubMed

    Akiyama, Kousuke; Yamamoto, Kazutaka; Mineno, Tomoko; Okawa, Masafumi; Kinjo, Junei; Yoshimitsu, Hitoshi; Nohara, Toshihiro; Ono, Masateru

    2014-01-01

    Three new acylated methyl glycosides and two new acylated glycosidic acid methyl esters were isolated after treatment of the crude ether-insoluble resin glycoside (convolvulin) fraction from seeds of Quamoclit pennata BOJER (Convolvulaceae) with indium(III) chloride in methanol. Their structures were elucidated on the basis of spectroscopic data and chemical conversions.

  1. Apple flavonols during fruit adaptation to solar radiation: spectral features and technique for non-destructive assessment.

    PubMed

    Merzlyak, Mark N; Solovchenko, Alexei E; Smagin, Alexei I; Gitelson, Anatoly A

    2005-02-01

    Spectral properties of flavonols of three varieties (Golden Delicious, Antonovka, and Renet Simirenko) of anthocyanin-free apple fruit were investigated with reflectance spectroscopy. The results of spectral and biochemical analyses suggested that fruit reflectance in a broad spectral range 365-430 nm is strongly dependent on and, in sunlit fruit surfaces, governed by flavonols. The build up of peel flavonols (mainly rutin and other quercetin glycosides) resulted in a dramatic decrease of fruit reflectance in this range, flattening of the spectrum, and extending the region with low reflectance (4-5%) to ca. 410 nm. The spectral features observed suggest that flavonols contribute significantly to screening of excessive radiation, not only UV-A, but in the short-wave bands of chlorophyll and carotenoid absorption in the visible part of the spectrum as well. To retrieve quantitatively flavonol content from reflectance spectra, we tested the applicability of an inversion technique developed for non-destructive leaf pigment assessment. The model for flavonol content assessment was suggested in the form (R(-1)410 - R(-1)460)R800, where Rlambda is reflectance at wavelength lambda. The model was linearly related to flavonol content between 8 and 220nmol/cm2 with the coefficient of determination r2=0.92 and root mean square error of flavonol estimation of 20 nmol/ cm2 regardless of cultivar, chlorophyll, and carotenoid content.

  2. Bioavailability and health effects of dietary flavonols in man.

    PubMed

    Hollman, P C; Katan, M B

    1998-01-01

    Flavonoids are polyphenolic compounds that occur ubiquitously in foods of plant origin. Over 4000 different flavonoids have been described, and they are categorized into flavonols, flavones, catechins, flavanones, anthocyanidins, and isoflavonoids. Flavonoids have a variety of biological effects in numerous mammalian cell systems, as well as in vivo. Recently much attention has been paid to their antioxidant properties and to their inhibitory role in various stages of tumour development in animal studies. Quercetin, the major representative of the flavonol subclass, is a strong antioxidant, and prevents oxidation of low density lipoproteins in vitro. Oxidized low density lipoproteins are atherogenic, and are considered to be a crucial intermediate in the formation of atherosclerotic plaques. This agrees with observations in epidemiological studies that the intake of flavonols and flavones was inversely associated with subsequent coronary heart disease. However, no effects of flavonols on cancer were found in these studies. The extent of absorption of flavonoids is an important unsolved problem in judging their many alleged health effects. Flavonoids present in foods were considered non-absorbable because they are bound to sugars as beta-glycosides. Only free flavonoids without a sugar molecule, the so-called aglycones were thought to be able to pass through the gut wall. Hydrolysis only occurs in the colon by microorganisms, which at the same time degrade flavonoids. We performed a study to quantify absorption of various dietary forms of quercetin. To our surprise, the quercetin glycosides from onions were absorbed far better than the pure aglycone. Subsequent pharmacokinetic studies with dietary quercetin glycosides showed marked differences in absorption rate and bioavailability. Absorbed quercetin was eliminated only slowly from the blood. The metabolism of flavonoids has been studied frequently in various animals, but very few data in humans are available. Two

  3. Kaempferol glycosides in the flowers of carnation and their contribution to the creamy white flower color.

    PubMed

    Iwashina, Tsukasa; Yamaguchi, Masa-atsu; Nakayama, Masayoshi; Onozaki, Takashi; Yoshida, Hiroyuki; Kawanobu, Shuji; Onoe, Hiroshi; Okamura, Masachika

    2010-12-01

    Three flavonol glycosides were isolated from the flowers of carnation cultivars 'White Wink' and 'Honey Moon'. They were identified from their UV, MS, 1H and 13C NMR spectra as kaempferol 3-O-neohesperidoside, kaempferol 3-O-sophoroside and kaempferol 3-O-glucosyl-(1 --> 2)-[rhamnosyl-(1 --> 6)-glucoside]. Referring to previous reports, flavonols occurring in carnation flowers are characterized as kaempferol 3-O-glucosides with additional sugars binding at the 2 and/or 6-positions of the glucose. The kaempferol glycoside contents of a nearly pure white flower and some creamy white flower lines were compared. Although the major glycoside was different in each line, the total kaempferol contents of the creamy white lines were from 5.9 to 20.9 times higher than the pure white line. Thus, in carnations, kaempferol glycosides surely contribute to the creamy tone of white flowers. PMID:21299117

  4. New benzophenone and quercetin galloyl glycosides from Psidium guajava L.

    PubMed

    Matsuzaki, Keiichi; Ishii, Rie; Kobiyama, Kaori; Kitanaka, Susumu

    2010-07-01

    New benzophenone and flavonol galloyl glycosides were isolated from an 80% MeOH extract of Psidium guajava L. (Myrtaceae) together with five known quercetin glycosides. The structures of the novel glycosides were elucidated to be 2,4,6-trihydroxybenzophenone 4-O-(6''-O-galloyl)-beta-D: -glucopyranoside (1, guavinoside A), 2,4,6-trihydroxy-3,5-dimethylbenzophenone 4-O-(6''-O-galloyl)-beta-D: -glucopyranoside (2, guavinoside B), and quercetin 3-O-(5''-O-galloyl)-alpha-L: -arabinofuranoside (3, guavinoside C) by NMR, MS, UV, and IR spectroscopies. Isolated phenolic glycosides showed significant inhibitory activities against histamine release from rat peritoneal mast cells, and nitric oxide production from a murine macrophage-like cell line, RAW 264.7.

  5. Biochemical and Molecular Characterization of a Flavonoid 3-O-glycosyltransferase Responsible for Anthocyanins and Flavonols Biosynthesis in Freesia hybrida

    PubMed Central

    Sun, Wei; Liang, Lingjie; Meng, Xiangyu; Li, Yueqing; Gao, Fengzhan; Liu, Xingxue; Wang, Shucai; Gao, Xiang; Wang, Li

    2016-01-01

    The glycosylation of flavonoids increases their solubility and stability in plants. Flowers accumulate anthocyanidin and flavonol glycosides which are synthesized by UDP-sugar flavonoid glycosyltransferases (UFGTs). In our previous study, a cDNA clone (Fh3GT1) encoding UFGT was isolated from Freesia hybrida, which was preliminarily proved to be invovled in cyanidin 3-O-glucoside biosynthesis. Here, a variety of anthocyanin and flavonol glycosides were detected in flowers and other tissues of F. hybrida, implying the versatile roles of Fh3GT1 in flavonoids biosynthesis. To further unravel its multi-functional roles, integrative analysis between gene expression and metabolites was investigated. The results showed expression of Fh3GT1 was positively related to the accumulation of anthocyanins and flavonol glycosides, suggesting its potential roles in the biosynthesis of both flavonoid glycosides. Subsequently, biochemical analysis results revealed that a broad range of flavonoid substrates including flavonoid not naturally occurred in F. hybrida could be recognized by the recombinant Fh3GT1. Both UDP-glucose and UDP-galactose could be used as sugar donors by recombinant Fh3GT1, although UDP-galactose was transferred with relatively low activity. Furthermore, regiospecificity analysis demonstrated that Fh3GT1 was able to glycosylate delphinidin at the 3-, 4-′, and 7- positions in a sugar-dependent manner. And the introduction of Fh3GT1 into Arabidopsis UGT78D2 mutant successfully restored the anthocyanins and flavonols phenotypes caused by lost-of-function of the 3GT, indicating that Fh3GT1 functions as a flavonoid 3-O-glucosyltransferase in vivo. In summary, these results demonstrate that Fh3GT1 is a flavonoid 3-O-glycosyltransferase using UDP-glucose as the preferred sugar donor and may involve in flavonoid glycosylation in F. hybrida. PMID:27064818

  6. Profiling of primary metabolites and flavonols in leaves of two table grape varieties collected from semiarid and temperate regions.

    PubMed

    Harb, Jamil; Alseekh, Saleh; Tohge, Takayuki; Fernie, Alisdair R

    2015-09-01

    Cultivation of grapes in West Bank - Palestine is very old and a large number of grape varieties exist as a result of continuous domestication over thousands of years. This rich biodiversity has highly influenced the consumer behavior of local people, who consume both grape berries and leaves. However, studies that address the contents of health-promoting metabolites in leaves are scarce. Accordingly the aim of this study is to assess metabolite levels in leaves of two grape varieties that were collected from semiarid and temperate regions. Metabolic profiling was conducted using GC-MS and LC-MS. The obtained results show that abiotic stresses in the semiarid region led to clear changes in primary metabolites, in particular in amino acids, which exist at very high levels. By contrast, qualitative and genotype-dependent differences in secondary metabolites were observed, whereas abiotic stresses appear to have negligible effect on the content of these metabolites. The qualitative difference in the flavonol profiles between the two genotypes is most probably related to differential expression of specific genes, in particular flavonol 3-O-rhamnosyltransferase, flavonol-3-O-glycoside pentosyltransferases and flavonol-3-O-d-glucosidel-rhamnosyltransferase by 'Beituni' grape leaves, which led to much higher levels of flavonols with rutinoside, pentoside, and rhamnoside moieties with this genotype.

  7. [Hypoglycemic and hypolipidemic effects of quercetin and its glycosides].

    PubMed

    Yan, Shu-xia; Li, Xian; Sun, Chong-de; Chen, Kun-song

    2015-12-01

    Quercetin and its glycosides are important flavonols in traditional herbal drugs and plant-derived food, and they have diverse hiological activities such as antioxidant, anticarcinogenic, anti-inflammatory, hypoglycemic and hypolipidemic activities. Numerous studies have demonstrated that quercetin and its glycosides were effective in the prevention and treatment of non-infectious chronic disease such as diabetes, obesity, and hyperlipidemia. They can regulate glucose and lipid metaholism through different mechanisms. They can decrease blood glucose via protecting pancreatic/p cells or/and improving insulin sensitivity. Also, they have lipid-lowering effects, which may be the result of regulation of lipid catabolism or/and anabolism. Their distributions, as well as the hypoglycemic and hypolipidemic effects are reviewed in this paper. In addition, further bioactivities as well as their dose-activity relationship, structure-activity relationship, bioavailability, and future clinical application of quercetin and its glycosides are discussed and proposed. PMID:27141664

  8. Anthocyanidins and Flavonols, Major nod Gene Inducers from Seeds of a Black-Seeded Common Bean (Phaseolus vulgaris L.) 1

    PubMed Central

    Hungria, Mariangela; Joseph, Cecillia M.; Phillips, Donald A.

    1991-01-01

    Eleven compounds released from germinating seeds of a black-seeded bean (Phaseolus vulgaris L., cv PI165426CS) induce transcription of nod genes in Rhizobium leguminosarum biovar phaseoli. Aglycones from 10 of those compounds were identified by spectroscopic methods (ultraviolet/visible, proton nuclear magnetic resonance, and mass spectroscopy), and their biological activities were demonstrated by induction of β-galactosidase activity in R. leguminosarum strains containing nodA-lacZ or nodC-lacZ fusions controlled by R. leguminosarum biovar phaseoli nodD genes. By making comparisons with authentic standards, the chemical structures for aglycones from the 10 molecules were confirmed as being anthocyanidins (delphinidin, petunidin, and malvidin) and flavonols (myricetin, quercetin, and kaempferol). All anthocyanidins and flavonols had 3-O-glycosylation and free hydroxyl groups at the 4′, 5, and 7 positions. Hydrolysis experiments showed that the mean concentration required for half-maximum nod gene induction (I50) by the 10 glycosides was about half that of the corresponding aglycones. The mean I50 value for the three anthocyanidins (360 nanomolar) was less (P ≤ 0.05) than that of the three flavonol aglycones (980 nanomolar). Each seed released approximately 2500 nanomoles of anthocyanidin and 450 nanomoles of flavonol nod gene inducers in conjugated forms during the first 6 hours of imbibition. Based on amounts and activities of the compounds released, anthocyanins contributed approximately 10-fold more total nod-inducing activity than flavonol glycosides. These anthocyanidins from bean seeds represent the first nod-inducing compounds identified from that group of flavonoids. PMID:16668462

  9. Anthocyanidins and Flavonols, Major nod Gene Inducers from Seeds of a Black-Seeded Common Bean (Phaseolus vulgaris L.).

    PubMed

    Hungria, M; Joseph, C M; Phillips, D A

    1991-10-01

    Eleven compounds released from germinating seeds of a black-seeded bean (Phaseolus vulgaris L., cv PI165426CS) induce transcription of nod genes in Rhizobium leguminosarum biovar phaseoli. Aglycones from 10 of those compounds were identified by spectroscopic methods (ultraviolet/visible, proton nuclear magnetic resonance, and mass spectroscopy), and their biological activities were demonstrated by induction of beta-galactosidase activity in R. leguminosarum strains containing nodA-lacZ or nodC-lacZ fusions controlled by R. leguminosarum biovar phaseoli nodD genes. By making comparisons with authentic standards, the chemical structures for aglycones from the 10 molecules were confirmed as being anthocyanidins (delphinidin, petunidin, and malvidin) and flavonols (myricetin, quercetin, and kaempferol). All anthocyanidins and flavonols had 3-O-glycosylation and free hydroxyl groups at the 4', 5, and 7 positions. Hydrolysis experiments showed that the mean concentration required for half-maximum nod gene induction (I(50)) by the 10 glycosides was about half that of the corresponding aglycones. The mean I(50) value for the three anthocyanidins (360 nanomolar) was less (P flavonol aglycones (980 nanomolar). Each seed released approximately 2500 nanomoles of anthocyanidin and 450 nanomoles of flavonol nod gene inducers in conjugated forms during the first 6 hours of imbibition. Based on amounts and activities of the compounds released, anthocyanins contributed approximately 10-fold more total nod-inducing activity than flavonol glycosides. These anthocyanidins from bean seeds represent the first nod-inducing compounds identified from that group of flavonoids.

  10. Flavonol tetraglycosides and other constituents from leaves of Styphnolobium japonicum (Leguminosae) and related taxa.

    PubMed

    Kite, Geoffrey C; Stoneham, Charlotte A; Veitch, Nigel C

    2007-05-01

    Two flavonol tetraglycosides comprising a trisaccharide at C-3 and a monosaccharide at C-7 were isolated from the leaves of Styphnolobium japonicum (L.) Schott and characterised as the 3-O-alpha-rhamnopyranosyl(1-->2)[alpha-rhamnopyranosyl(1-->6)]-beta-glucopyranoside-7-O-alpha-rhamnopyranosides of quercetin and kaempferol. The 3-O-alpha-rhamnopyranosyl(1-->2)[alpha-rhamnopyranosyl(1-->6)]-beta-galactopyranoside-7-O-alpha-rhamnopyranoside of kaempferol, the 3-O-alpha-rhamnopyranosyl(1-->2)[alpha-rhamnopyranosyl(1-->6)]-beta-glucopyranosides of kaempferol and quercetin and the 3-O-alpha-rhamnopyranosyl(1-->2)[alpha-rhamnopyranosyl(1-->6)]-beta-galactopyranoside of kaempferol were also obtained from this species for the first time. Some or all of these flavonol tetra- and triglycosides were detected in 17 of 18 specimens of S. japonicum examined from living and herbarium material, although the most abundant flavonoid in the leaves was generally quercetin 3-O-alpha-rhamnopyranosyl(1-->6)-beta-glucopyranoside (rutin). The triglycosides, but not the tetraglycosides, were detected in herbarium specimens of Styphnolobium burseroides M. Sousa, Rudd & Medrano and Styphnolobium monteviridis M. Sousa & Rudd, but specimens of Styphnolobium affine (Torrey & A. Gray) Walp. contained a different profile of flavonol glycosides. The flavonol tetra- and triglycosides of S. japonicum were also present in leaves of Cladrastis kentukea (Dum. Cours.) Rudd, a representative of a genus placed close to Styphnolobium in current molecular phylogenies. An additional constituent obtained from leaves of Styphnolobium japonicum was identified as the maltol derivative, 3-hydroxy-2-methyl-4H-pyran-4-one 3-O-(4'-O-p-coumaroyl-6'-O-(3-hydroxy-3-methylglutaroyl))-beta-glucopyranoside. PMID:17462679

  11. A flavonol tetraglycoside from Sophora japonica seeds.

    PubMed

    Wang, Jing-Hua; Lou, Feng-Chang; Wang, Ya-Lin; Tang, Yu-Ping

    2003-06-01

    A flavonol tetraglycoside, kaempferol 3-O-alpha-L-rhamnopyranosyl(1-->6)-beta-D-glucopyranosyl(1-->2)- beta-D-glucopyranoside-7-O-alpha-L rhamnopyranoside, together with nine known compounds were isolated from the seeds of Sophora japonica L. Their structures were elucidated on the basis of spectral and chemical evidence. PMID:12770599

  12. Evaluation of a Method to Determine Flavonol Aglycones in Ginkgo biloba Dietary Supplement Crude Materials and Finished Products by High-Performance Liquid Chromatography

    PubMed Central

    Gray, Dean; LeVanseler, Kerri; Pan, Meide; Waysek, Edward H.; Baugh, S.; Chandra, A.; Meibos, R.; Peng, T.; Perez, R.; Reif, K.; Roman, M.; Rousch, J.; Skamarack, J.; Solyom, A.; Sullivan, D.; Young, K.

    2008-01-01

    An interlaboratory study was conducted for evaluation of a method to determine the flavonol aglycones quercetin, kaempferol, and isorhamnetin in Ginkgo biloba products. The method calculates total glycosides based on these aglycones formed after acid hydrolysis. Twelve matrixes were chosen for study by 12 collaborating laboratories in 2 countries. Test materials included crude leaf material, standardized dry powder extract, single and multiple entity finished products, ethanol and glycerol tinctures, and National Institute of Standards and Technology (NIST) standard reference materials (SRMs). Results from 11 laboratories were used for the final calculations. Eight of the 12 matrixes evaluated produced acceptable results for total flavonol glycosides, with HorRat scores ranging from 1.31 to 2.05; repeatability relative standard deviations (RSDr) from 1.46 to 4.14; and reproducibility relative standard deviations (RSDR) from 4.67 to 9.69. These 8 matrixes consisted primarily of simple dosage forms (e.g., dry powder extracts, crude leaf samples, liquid extracts, and SRMs) and a single tablet product (Ginkgo Awareness). Four additional matrixes, consisting of 3 tablets and 1 soft gel product (Ginkgold, Ginkoba, Ginkogen, and Ginkgo Phytosome, respectively), showed greater total flavonol glycoside HorRat scores in comparison, ranging from 2.39 to 5.13, with RSDr values from 2.83 to 8.16, and RSDR values from 8.53 to 20.4. Based on the results presented here, the method is recommended for Official First Action for determination of total flavonol glycosides calculated from quercetin, kaempferol, and isorhamnetin in dry powder extracts, crude leaf material, liquid extracts, and a select finished product, Ginkgo Awareness. PMID:17373435

  13. Pentasaccharide resin glycosides from Ipomoea cairica and their cytotoxic activities.

    PubMed

    Yu, Bangwei; Luo, Jianguang; Wang, Junsong; Zhang, Dongming; Yu, Shishan; Kong, Lingyi

    2013-11-01

    Six partially acylated pentasaccharide resin glycosides, cairicosides A-F, were isolated from the aerial parts of Ipomoea cairica. These compounds were characterized as a group of macrolactones of simonic acid A, partially acylated with different organic acids. The lactonization site of 11S-hydroxyhexadecanoic acid (jalapinolic acid) was bound to the second saccharide moiety at C-3 in cairicosides A-E, while at C-2 in cairicoside F. Structures were established by spectroscopic and chemical methods. Compounds cairicosides A-E exhibited moderate cytotoxicity against a small panel of human tumor cell lines with IC50 values in the range of 4.28-14.31μM.

  14. High-flavonol tomatoes resulting from the heterologous expression of the maize transcription factor genes LC and C1.

    PubMed

    Bovy, Arnaud; de Vos, Ric; Kemper, Mark; Schijlen, Elio; Almenar Pertejo, Maria; Muir, Shelagh; Collins, Geoff; Robinson, Sue; Verhoeyen, Martine; Hughes, Steve; Santos-Buelga, Celestino; van Tunen, Arjen

    2002-10-01

    Flavonoids are a group of polyphenolic plant secondary metabolites important for plant biology and human nutrition. In particular flavonols are potent antioxidants, and their dietary intake is correlated with a reduced risk of cardiovascular diseases. Tomato fruit contain only in their peel small amounts of flavonoids, mainly naringenin chalcone and the flavonol rutin, a quercetin glycoside. To increase flavonoid levels in tomato, we expressed the maize transcription factor genes LC and C1 in the fruit of genetically modified tomato plants. Expression of both genes was required and sufficient to upregulate the flavonoid pathway in tomato fruit flesh, a tissue that normally does not produce any flavonoids. These fruit accumulated high levels of the flavonol kaempferol and, to a lesser extent, the flavanone naringenin in their flesh. All flavonoids detected were present as glycosides. Anthocyanins, previously reported to accumulate upon LC expression in several plant species, were present in LC/C1 tomato leaves but could not be detected in ripe LC/C1 fruit. RNA expression analysis of ripening fruit revealed that, with the exception of chalcone isomerase, all of the structural genes required for the production of kaempferol-type flavonols and pelargonidin-type anthocyanins were induced strongly by the LC/C1 transcription factors. Expression of the genes encoding flavanone-3'-hydroxylase and flavanone-3'5'-hydroxylase, which are required for the modification of B-ring hydroxylation patterns, was not affected by LC/C1. Comparison of flavonoid profiles and gene expression data between tomato leaves and fruit indicates that the absence of anthocyanins in LC/C1 fruit is attributable primarily to an insufficient expression of the gene encoding flavanone-3'5'-hydroxylase, in combination with a strong preference of the tomato dihydroflavonol reductase enzyme to use the flavanone-3'5'-hydroxylase reaction product dihydromyricetin as a substrate.

  15. Methylenebisnicotiflorin: a rare methylene-bridged bisflavonoid glycoside from ripe Pu-er tea.

    PubMed

    Tao, Mu-Ke; Xu, Min; Zhang, Han; Chen, Hui; Liu, Chang; Zhu, Hong-Tao; Wang, Dong; Yang, Chong-Ren; Zhang, Ying-Jun

    2016-01-01

    A new methylene-bridged dimeric flavonol glycoside, methylenebisnicotiflorin (1), was isolated from ripe Pu-er tea, along with 10 known flavonoids (2-11) and seven known phenolic compounds (12-18). The structure elucidation was based on spectroscopic analysis. Among them, 1,3-dihydroxyphenyl-2-O-sulfate (13), 2,3,4-trihydroxybenzoic acid (16) and 3,3',4,4'-tetrahydroxybiphenyl (18) are reported from tea plants for the first time.

  16. Distinctive antioxidant and antiinflammatory effects of flavonols.

    PubMed

    Wang, Lisu; Tu, Yi-Chen; Lian, Tzi-Wei; Hung, Jing-Ting; Yen, Jui-Hung; Wu, Ming-Jiuan

    2006-12-27

    The antioxidant and antiinflammatory effects of flavonols have been suggested to be structure-related. Results revealed that selected flavonols, including fisetin (F), kaempferol (K), morin (MO), myricetin (MY), and quercetin (Q), exhibited distinctive free radical scavenging properties against different kinds of free radicals. The H donation (DPPH bleaching) potential was Q > F approximately equals MY > MO > K, indicating that the presence of a 3',4'-catechol moiety in the B ring correlated with high activity. The 4'-OH in the B ring was suggested to be important for reducing xanthing/xanthine oxidase-generated superoxide; while an additional OH moiety on the ortho sites (3' or 5') attenuated the effect as the observed inhibitory potency was K approximately equals MO > Q > F > MY. The relative inhibitory effect for Fenton-mediated hydroxyl radical was K approximately equals MO approximately equals Q > F > MY. This result implies the involvement of 4-keto, 5-OH region in Fe++ chelating and the negative effect of pyrogallol moiety in the B ring. Similar to the inhibitory activity against a N-formyl-methionyl-leucyl-phenylalanine (f-MLP)-stimulated oxidative burst in human polymorphonuclear neutrophils (PMN), our result showed that the structural peculiarity of the di-OH in the B ring obviously rendered F, Q, and MO more potent as ROS inhibitors than MY and K, which have tri- and mono-OH in the B ring, respectively. All of the previous data indicated that the structure prerequisite to reinforce the free radical scavenging activity varies with the type of free radical. We further analyzed the effects of flavonols on nitric oxide (NO) production in endotoxin-stimulated murine macrophages, RAW264.7 cells. Results showed that all flavonols (up to 10 microM) inhibited NO production without exerting detectable cytotoxicity. F, K, and Q dose-dependently repressed iNOS mRNA expression and prostaglandin E2 (PGE2) production, in part through an attenuating NF-kappaB signaling

  17. Antioxidant flavonols from fruits, vegetables and beverages: measurements and bioavailability.

    PubMed

    Crozier, A; Burns, J; Aziz, A A; Stewart, A J; Rabiasz, H S; Jenkins, G I; Edwards, C A; Lean, M E

    2000-01-01

    Flavonols are polyphenolic secondary plant metabolites that are present in varying levels in commonly consumed fruits, vegetables and beverages. Flavonols have long held an interest for nutritionists, which has increased following a Dutch study in the early 1990's showing that dietary intake of flavonols was inversely correlated with the incidence of coronary heart disease. The main factors that have hindered workers in the field of flavonol research are (i) the accurate measurement of these compounds in foods and biological samples, and (ii) a dearth of information on their absorption and metabolism. This review aims to highlight the work of the authors in attempting to clarify the situation. The sensitive and selective HPLC procedure to identify and quantify common flavonols and their sugar conjugates is described. In addition, the results of an on-going screening program into the flavonol content of common produce and beverages are presented. The bioavailability of dietary flavonols is discussed with reference to an intervention study with onions, as well as pilot studies with tea, red wine and cherry tomatoes. It is concluded that flavonols are absorbable and accumulate in plasma and that consuming high flavonol-containing varieties of fruits and vegetables and particular types of beverages could increase their circulatory levels. PMID:15693274

  18. Arabidopsis thaliana β-glucosidase BGLU15 attacks flavonol 3-O-β-glucoside-7-O-α-rhamnosides.

    PubMed

    Roepke, Jonathon; Bozzo, Gale G

    2015-01-01

    Kaempferol and quercetin 3-O-β-glucoside-7-O-α-rhamnoside (K3G7R and Q3G7R, respectively) are major flavonol bisglycosides accumulating in Arabidopsis thaliana with synergistic abiotic stresses (i.e., nitrogen deficiency and low temperature, NDLT). However, these molecules disappear rapidly during recovery from NDLT. Typically, catabolism of related chemicals relies on β-glucosidase (BGLU) action. Evidence for flavonol 3-O-β-glucoside-7-O-α-rhamnoside BGLU activity is provided here. Major losses of Q3G7R and K3G7R coincided with an approximate 250% induction in flavonol 3-O-β-glucoside-7-O-α-rhamnoside BGLU activity within 2days of NDLT recovery relative to plants cultured under nitrogen sufficiency and high temperature (NSHT, control). QTOF-MS/MS established the product of Q3G7R hydrolysis in the presence of Arabidopsis cell free extracts was quercetin 7-O-α-rhamnoside. A phylogenetic analysis of the Arabidopsis glycoside hydrolase family 1 identified BGLU15 (At2g44450) and five other members that cluster with Fabaceae hydrolases known to attack isoflavones and isoflavonoids, which are structurally somewhat related to flavonol 3-O-β-glucoside-7-O-α-rhamnosides. Real time quantitative PCR analysis established a 300% higher expression of BGLU15 within 1day of the recovery from NDLT relative to control plants; lower or negligible changes in expression were evident for the remaining BGLUs. Recombinant thioredoxin-His6-tagged mature BGLU15 protein was expressed in Escherichia coli and purified to homogeneity. A comparison of a wide spectrum of β-glucosides showed that recombinant BGLU15 preferentially hydrolyses the 3-O-β-glucosides of flavonols, but does not attack quercetin 3-O-α-rhamnoside, quercetin 3-O-β-galactoside and rutin. BGLU15 displayed the highest catalytic efficiency for Q3G7R and K3G7R yielding their respective 7-O-rhamnosides as products; flavonol 3-O-glucosides were also attacked, albeit with lower efficiency. Together, it appears the

  19. Oxidative acylation using thioacids

    NASA Technical Reports Server (NTRS)

    Liu, R.; Orgel, L. E.

    1997-01-01

    Several important prebiotic reactions, including the coupling of amino acids into polypeptides by the formation of amide linkages, involve acylation. Theae reactions present a challenge to the understanding of prebiotic synthesis. Condensation reactions relying on dehydrating agents are either inefficient in aqueous solution or require strongly acidic conditions and high temperatures. Activated amino acids such as thioester derivatives have therefore been suggested as likely substrates for prebiotic peptide synthesis. Here we propose a closely related route to amide bond formation involving oxidative acylation by thioacids. We find that phenylalanine, leucine and phenylphosphate are acylated efficiently in aqueous solution by thioacetic acid and an oxidizing agent. From a prebiotic point of view, oxidative acylation has the advantage of proceeding efficiently in solution and under mild conditions. We anticipate that oxidative acylation should prove to be a general method for activating carboxylic acids, including amino acids.

  20. Cardiac glycoside overdose

    MedlinePlus

    ... found in the leaves of the digitalis (foxglove) plant. This plant is the original source of this medicine. People ... Digitoxin (Crystodigin) Digoxin (Lanoxicaps, Lanoxin) Besides the foxglove plant, cardiac glycosides also occur naturally in plants such ...

  1. Characterization of Brassica napus Flavonol Synthase Involved in Flavonol Biosynthesis in Brassica napus L.

    PubMed

    Vu, Tien Thanh; Jeong, Chan Young; Nguyen, Hoai Nguyen; Lee, Dongho; Lee, Sang A; Kim, Ji Hye; Hong, Suk-Whan; Lee, Hojoung

    2015-09-01

    Recently, Brassica napus has become a very important crop for plant oil production. Flavonols, an uncolored flavonoid subclass, have a high antioxidative effect and are known to have antiproliferative, antiangiogenic, and neuropharmacological properties. In B. napus, some flavonoid structural genes have been identified, such as, BnF3H-1, BnCHS, and BnC4H-1. However, no studies on FLS genes in B. napus have been conducted. Thus, in this study, we cloned and characterized the function of BnFLS gene B. napus. By overexpression of the BnFLS gene, flavonol (kaempferol and quercetin) levels were recovered in the Arabidopsis atfls1-ko mutant. In addition, we found that the higher endogenous flavonol levels of BnFLS-ox in vitro shoots correlated with slightly higher ROS scavenging activities. Thus, our results indicate that the BnFLS gene encodes for a BnFLS enzyme that can be manipulated to specifically increase flavonol accumulation in oilseed plants and other species such as Arabidopsis.

  2. From UVR8 to flavonol synthase: UV-B-induced gene expression in Sauvignon blanc grape berry.

    PubMed

    Liu, Linlin; Gregan, Scott; Winefield, Chris; Jordan, Brian

    2015-05-01

    The aim of this research was to determine the effect of development and UV-B on flavonols and the regulation of gene activity in Vitis vinifera L. var. Sauvignon blanc grapes. Particular emphasis was placed on gene activity associated with the low and high fluence UV-B responses. Flavonols, particularly quercetin and kaempferol glycosides, increased substantially upon fruit exposure due to UV-B, with spatial analysis locating the changes to the berry skin. Of five VvFLS genes in grapes, two (VvFLS4 and 5) were found to be transcriptionally active, with VvFLS4 also being responsive to UV-B but VvFLS5 was not. Of the transcription factors known to regulate FLS (VvMYB12, VvMYCA1 and VvWDRs), only VvMYB12 was found to be responsive to UV-B. A number of candidate genes associated with the low and high UV-B fluence responses were also studied (VvUVR8, VvHY5, VvCOP1 and VvCHS; PR genes and VvMAPK3; respectively). The genes associated with the low fluence response exhibited transcriptional regulation in line with reports from other species, while the PR genes and VvMAPK3 only appeared to be responsive in a high UV-B fluence environment. Together, these data supports the view flavonol biosynthesis in grape is stimulated predominantly through the low fluence UV-B response pathway.

  3. Differentiation of flavonol glucoside and galactoside isomers combining chemical isopropylidenation with liquid chromatography-mass spectrometry analysis.

    PubMed

    de Souza, Lauro M; Dartora, Nessana; Scoparo, Camila T; Gorin, Philip A J; Iacomini, Marcello; Sassaki, Guilherme L

    2016-05-20

    Flavonol glycosides are important components of leaves from vascular plants. A lot of isomers of these compounds are produced by plants, making their analysis very difficult and causing many structural misinterpretations. Galactosides and glucosides as mono- or oligosaccharides yield many diastereoisomers, hindering the analysis by mass spectrometry. In order to enable the mass spectrometric distinctions of these isomers, in this work we combine an isopropylidene based chemical derivatization with liquid chromatography with multiple-stage mass spectrometry (LC-MS(n)) analysis. The isomers of flavonol triglycosides, after the reaction, yielded products with different molecular weight, therefore, they were no longer isomers, allowing their identification by MS(1) analysis. However, to the 4 isomers of flavonol diglycosides, only one yielded, after isopropylidenation, a product with different molecular weight. To the other 3 species, the incorporation of 2 isopropylidene groups retained them in the isomeric form. For such species, chromatographic separation and MS(n) detection targeting the lithium adducts of 3,4-O-isopropylidene-galactosyl or 4,6-O-isopropylidene-glucosyl residues (m/z 209.099) provided specific MS profile. PMID:27109198

  4. The role of glycosylation in flavonol-induced pollen germination.

    PubMed

    Taylor, L P; Strenge, D; Miller, K D

    1998-01-01

    Flavonols are small (C15) plant-specific molecules that are required for petunia and maize pollen to germinate. They exist in two chemical forms: the aglycone or glycosyl conjugates. Flavonol-deficient pollen is biochemically complemented by flavonol aglycones but not by the glycosylated forms that accumulate in wild type (WT) pollen. Coincident with the biochemical induction of germination, the added flavonol aglycone is rapidly converted to a galactoside and then to a glucosyl galactoside (diglycoside) that is identical to the compound present in WT pollen. A flavonol 3-O-galactosyltransferase (F3GalTase) activity has been identified that controls the formation of glycosylated flavonols in pollen. Importantly, this enzyme also catalyzes the reverse reaction, i.e. the production of the flavonol aglycone from the galactoside and UDP (Fig. 1). F3GalTase/RevGalTase therefore has the potential to control the level of the bioactive flavonol species and as a result, pollen germination. PMID:9781293

  5. Kaempferol 3-O-rhamnoside-7-O-rhamnoside is an endogenous flavonol inhibitor of polar auxin transport in Arabidopsis shoots

    PubMed Central

    Yin, Ruohe; Han, Kerstin; Heller, Werner; Albert, Andreas; Dobrev, Petre I; Zažímalová, Eva; Schäffner, Anton R

    2014-01-01

    Polar auxin transport (PAT) plays key roles in the regulation of plant growth and development. Flavonoids have been implicated in the inhibition of PAT. However, the active flavonoid derivative(s) involved in this process in vivo has not yet been identified. Here, we provide evidence that a specific flavonol bis-glycoside is correlated with shorter plant stature and reduced PAT. Specific flavonoid-biosynthetic or flavonoid-glycosylating steps were genetically blocked in Arabidopsis thaliana. The differential flavonol patterns established were analyzed by high-performance liquid chromatography (HPLC) and related to altered plant stature. PAT was monitored in stem segments using a radioactive [3H]-indole-3-acetic acid tracer. The flavonoid 3-O-glucosyltransferase mutant ugt78d2 exhibited a dwarf stature in addition to its altered flavonol glycoside pattern. This was accompanied by reduced PAT in ugt78d2 shoots. The ugt78d2-dependent growth defects were flavonoid dependent, as they were rescued by genetic blocking of flavonoid biosynthesis. Phenotypic and metabolic analyses of a series of mutants defective at various steps of flavonoid formation narrowed down the potentially active moiety to kaempferol 3-O-rhamnoside-7-O-rhamnoside. Moreover, the level of this compound was negatively correlated with basipetal auxin transport. These results indicate that kaempferol 3-O-rhamnoside-7-O-rhamnoside acts as an endogenous PAT inhibitor in Arabidopsis shoots. PMID:24251900

  6. Occurrence of flavonols in tomatoes and tomato-based products.

    PubMed

    Stewart, A J; Bozonnet, S; Mullen, W; Jenkins, G I; Lean, M E; Crozier, A

    2000-07-01

    The flavonol contents of 20 varieties of tomato fruit were investigated in relation to variety, size, season, and country of origin. Ten commonly consumed tomato-based food products were also assessed. Free and conjugated flavonols were identified and quantified using reversed-phase HPLC. Ninety-eight percent of flavonols detected in tomatoes were found to occur in the skin. Tomatoes contained, primarily as conjugates, quercetin and kaempferol. The main quercetin conjugate was identified as rutin (quercetin 3-rhamnosylglucoside) by LC-MS. The total flavonol content of the different varieties of tomato that were analyzed varied from 1.3 to 22.2 microgram/g of fresh weight (fw). Smaller cherry tomato fruits originating from warm sunny climates, such as Spain and Israel, were found to contain the highest concentration of flavonols. Among the tomato-based products investigated, tomato juice and tomato purée were rich in flavonols, containing 14-16 microgram/mL and 70 microgram/g fw, respectively. In contrast to fresh tomatoes, most tomato-based products contained significant amounts of free flavonols.

  7. Antioxidant and cytotoxic flavonols from Calotropis procera.

    PubMed

    Mohamed, Mona A; Hamed, Manal M; Ahmed, Wafaa S; Abdou, Allia M

    2011-01-01

    Phytochemical investigations of Calotropis procera leaves have led to the isolation of two new compounds: quercetagetin-6-methyl ether 3-O-beta-D-4C1-galacturonopyranoside (3) and (E)-3-(4-methoxyphenyl-2-O-beta-D-4C1 -glucopyranoside)-methyl propenoate (4), along with eleven known metabolites: nine flavonol and two cinnamic acid derivatives. All metabolites were isolated for the first time from the genus Calotropis, except for 1 isolated previously from Calotropis gigantea. The structures were determined by spectroscopic methods (UV, ESI-MS, 1H, 13C NMR, 1H-1H COSY, HSQC, and HMBC). The radical scavenging activity of the aqueous methanol extract and compounds 8-13 was measured by the 1,1-diphenyl-2-picrylhydrazyl (DPPH) method. Cytotoxic screening of the same compounds was carried out on brine shrimps as well.

  8. Characterization of flavonol conjugates in immature leaves of pak choi [Brassica rapa L. Ssp. chinensis L. (Hanelt.)] by HPLC-DAD and LC-MS/MS.

    PubMed

    Rochfort, Simone J; Imsic, Michael; Jones, Rod; Trenerry, V Craige; Tomkins, Bruce

    2006-06-28

    The flavonoid composition of immature leaves of pak choi [Brassica rapa L. ssp. chinensis L. (Hanelt.)] was investigated. Flavonol aglycone content was measured in 11 pak choi varieties, indicating significant differences (P < 0.05) in content between varieties and relatively high contents of kaempferol and isorhamnetin. Levels of quercetin ranged from 3.2 to 6.1 mg/100 g of dry weight (DW), whereas levels of isorhamnetin and kaempferol were significantly higher (8.1-35.1 and 36.0-102.6 mg/100 g of DW, respectively). A large number of glycoside and hydroxycinnamic acid derivatives of quercetin, kaempferol, and isorhamnetin were identified in cv. 'Shanghai' by LC/UV-DAD/ESI-MS/MS. The UV-DAD data allowed identification of hydroxycinnamic acid derivatives, but detailed MS/MS fragmentations were required for the structure elucidation. Pak choi could be a potentially important source of dietary flavonols, in particular, kaempferol and isorhamnetin.

  9. Isolation and characterization of stelladerol, a new antioxidant naphthalene glycoside, and other antioxidant glycosides from edible daylily (hemerocallis) flowers.

    PubMed

    Cichewicz, Robert H; Nair, Muraleedharan G

    2002-01-01

    Daylily (Hemerocallis spp.) flowers are utilized as an important ingredient in traditional Asian cuisine and are also valued for their reputed medicinal effects. In studies of the bioactive methanol and aqueous methanol extracts of lyophilized Hemerocallis cv. Stella de Oro flowers, kaempferol, quercetin, and isorhamnetin 3-O-glycosides (1-9), phenethyl beta-D-glucopyranoside (10), orcinol beta-D-glucopyranoside (11), phloretin 2'-O-beta-D-glucopyranoside (12), phloretin 2'-O-beta-D-xylopyranosyl-(1-->6)-beta-D-glucopyranoside (13), a new naphthalene glycoside, stelladerol (14), and an amino acid (longitubanine A) (15) have been isolated. All of these compounds were tested for their antioxidant and cyclooxygenase inhibitory activities. Stelladerol was found to possess strong antioxidant properties, inhibiting lipid oxidation by 94.6% +/- 1.4 at 10 microM in an in vitro assay. Several of the flavonol 3-O-glycoside isolates also demonstrated modest antioxidant activities at 10 microM. None of the isolates inhibited cyclooxygenase activity at 100 microM. PMID:11754548

  10. Flavonols in the Prevention of Diabetes-induced Vascular Dysfunction

    PubMed Central

    Leo, Chen-Huei

    2015-01-01

    Abstract: As flavonols are present in fruits and vegetables, they are consumed in considerable amounts in the diet. There is growing evidence that the well-recognized antioxidant, anti-inflammatory, and vasorelaxant actions of flavonols may, at least in part, result from modulation of biochemical signaling pathways and kinases. It is well established that diabetes is associated with increased cardiovascular morbidity and mortality. Despite clinical management of blood glucose levels, diabetes often results in cardiovascular disease. There is good evidence that endothelial dysfunction contributes significantly to the progression of diabetic cardiovascular diseases. This review describes the biological actions of flavonols that may ameliorate adverse cardiovascular events in diabetes. We discuss evidence that flavonols may be developed as novel pharmacological agents to prevent diabetes-induced vascular dysfunction. PMID:25387248

  11. Pentasaccharide resin glycosides from Ipomoea cairica and their cytotoxic activities.

    PubMed

    Yu, Bangwei; Luo, Jianguang; Wang, Junsong; Zhang, Dongming; Yu, Shishan; Kong, Lingyi

    2013-11-01

    Six partially acylated pentasaccharide resin glycosides, cairicosides A-F, were isolated from the aerial parts of Ipomoea cairica. These compounds were characterized as a group of macrolactones of simonic acid A, partially acylated with different organic acids. The lactonization site of 11S-hydroxyhexadecanoic acid (jalapinolic acid) was bound to the second saccharide moiety at C-3 in cairicosides A-E, while at C-2 in cairicoside F. Structures were established by spectroscopic and chemical methods. Compounds cairicosides A-E exhibited moderate cytotoxicity against a small panel of human tumor cell lines with IC50 values in the range of 4.28-14.31μM. PMID:23954073

  12. Acyl-Lipid Metabolism

    PubMed Central

    Li-Beisson, Yonghua; Shorrosh, Basil; Beisson, Fred; Andersson, Mats X.; Arondel, Vincent; Bates, Philip D.; Baud, Sébastien; Bird, David; DeBono, Allan; Durrett, Timothy P.; Franke, Rochus B.; Graham, Ian A.; Katayama, Kenta; Kelly, Amélie A.; Larson, Tony; Markham, Jonathan E.; Miquel, Martine; Molina, Isabel; Nishida, Ikuo; Rowland, Owen; Samuels, Lacey; Schmid, Katherine M.; Wada, Hajime; Welti, Ruth; Xu, Changcheng; Zallot, Rémi; Ohlrogge, John

    2013-01-01

    Acyl lipids in Arabidopsis and all other plants have a myriad of diverse functions. These include providing the core diffusion barrier of the membranes that separates cells and subcellular organelles. This function alone involves more than 10 membrane lipid classes, including the phospholipids, galactolipids, and sphingolipids, and within each class the variations in acyl chain composition expand the number of structures to several hundred possible molecular species. Acyl lipids in the form of triacylglycerol account for 35% of the weight of Arabidopsis seeds and represent their major form of carbon and energy storage. A layer of cutin and cuticular waxes that restricts the loss of water and provides protection from invasions by pathogens and other stresses covers the entire aerial surface of Arabidopsis. Similar functions are provided by suberin and its associated waxes that are localized in roots, seed coats, and abscission zones and are produced in response to wounding. This chapter focuses on the metabolic pathways that are associated with the biosynthesis and degradation of the acyl lipids mentioned above. These pathways, enzymes, and genes are also presented in detail in an associated website (ARALIP: http://aralip.plantbiology.msu.edu/). Protocols and methods used for analysis of Arabidopsis lipids are provided. Finally, a detailed summary of the composition of Arabidopsis lipids is provided in three figures and 15 tables. PMID:23505340

  13. Acyl-Lipid Metabolism

    PubMed Central

    Li-Beisson, Yonghua; Shorrosh, Basil; Beisson, Fred; Andersson, Mats X.; Arondel, Vincent; Bates, Philip D.; Baud, Sébastien; Bird, David; DeBono, Allan; Durrett, Timothy P.; Franke, Rochus B.; Graham, Ian A.; Katayama, Kenta; Kelly, Amélie A.; Larson, Tony; Markham, Jonathan E.; Miquel, Martine; Molina, Isabel; Nishida, Ikuo; Rowland, Owen; Samuels, Lacey; Schmid, Katherine M.; Wada, Hajime; Welti, Ruth; Xu, Changcheng; Zallot, Rémi; Ohlrogge, John

    2010-01-01

    Acyl lipids in Arabidopsis and all other plants have a myriad of diverse functions. These include providing the core diffusion barrier of the membranes that separates cells and subcellular organelles. This function alone involves more than 10 membrane lipid classes, including the phospholipids, galactolipids, and sphingolipids, and within each class the variations in acyl chain composition expand the number of structures to several hundred possible molecular species. Acyl lipids in the form of triacylglycerol account for 35% of the weight of Arabidopsis seeds and represent their major form of carbon and energy storage. A layer of cutin and cuticular waxes that restricts the loss of water and provides protection from invasions by pathogens and other stresses covers the entire aerial surface of Arabidopsis. Similar functions are provided by suberin and its associated waxes that are localized in roots, seed coats, and abscission zones and are produced in response to wounding. This chapter focuses on the metabolic pathways that are associated with the biosynthesis and degradation of the acyl lipids mentioned above. These pathways, enzymes, and genes are also presented in detail in an associated website (ARALIP: http://aralip.plantbiology.msu.edu/). Protocols and methods used for analysis of Arabidopsis lipids are provided. Finally, a detailed summary of the composition of Arabidopsis lipids is provided in three figures and 15 tables. PMID:22303259

  14. Acyl-lipid metabolism.

    PubMed

    Li-Beisson, Yonghua; Shorrosh, Basil; Beisson, Fred; Andersson, Mats X; Arondel, Vincent; Bates, Philip D; Baud, Sébastien; Bird, David; Debono, Allan; Durrett, Timothy P; Franke, Rochus B; Graham, Ian A; Katayama, Kenta; Kelly, Amélie A; Larson, Tony; Markham, Jonathan E; Miquel, Martine; Molina, Isabel; Nishida, Ikuo; Rowland, Owen; Samuels, Lacey; Schmid, Katherine M; Wada, Hajime; Welti, Ruth; Xu, Changcheng; Zallot, Rémi; Ohlrogge, John

    2013-01-01

    Acyl lipids in Arabidopsis and all other plants have a myriad of diverse functions. These include providing the core diffusion barrier of the membranes that separates cells and subcellular organelles. This function alone involves more than 10 membrane lipid classes, including the phospholipids, galactolipids, and sphingolipids, and within each class the variations in acyl chain composition expand the number of structures to several hundred possible molecular species. Acyl lipids in the form of triacylglycerol account for 35% of the weight of Arabidopsis seeds and represent their major form of carbon and energy storage. A layer of cutin and cuticular waxes that restricts the loss of water and provides protection from invasions by pathogens and other stresses covers the entire aerial surface of Arabidopsis. Similar functions are provided by suberin and its associated waxes that are localized in roots, seed coats, and abscission zones and are produced in response to wounding. This chapter focuses on the metabolic pathways that are associated with the biosynthesis and degradation of the acyl lipids mentioned above. These pathways, enzymes, and genes are also presented in detail in an associated website (ARALIP: http://aralip.plantbiology.msu.edu/). Protocols and methods used for analysis of Arabidopsis lipids are provided. Finally, a detailed summary of the composition of Arabidopsis lipids is provided in three figures and 15 tables. PMID:23505340

  15. Calysolins I-IV, resin glycosides from Calystegia soldanella.

    PubMed

    Takigawa, Ayako; Muto, Haruka; Kabata, Kiyotaka; Okawa, Masafumi; Kinjo, Junei; Yoshimitsu, Hitoshi; Nohara, Toshihiro; Ono, Masateru

    2011-11-28

    Four new resin glycosides having intramolecular cyclic ester structures (jalapins), named calysolins I-IV (1-4), were isolated from the methanol extract of leaves, stems, and roots of Calystegia soldanella , along with one known jalapin (5) derivative. The structures of 1-4 were determined on the basis of spectroscopic data and chemical evidence. They fall into two types, one having a 22-membered ring (1 and 4) and the other with a 27-membered ring (2 and 3). The sugar moieties of 1-4 were partially acylated by some organic acids. Compound 4 is the first example of a hexaglycoside of jalapin.

  16. Allometric analysis of the induced flavonols on the leaf surface of wild tobacco (Nicotiana attenuata).

    PubMed

    Roda, Amy L; Oldham, Neil J; Svatos, Ales; Baldwin, Ian T

    2003-02-01

    Trichomes excrete secondary metabolites that may alter the chemical composition of the leaf surface, reducing damage caused by herbivores, pathogens and abiotic stresses. We examined the surface exudates produced by Nicotiana attenuata Torr. Ex Wats., a plant known to contain and secrete a number of secondary metabolites that are toxic or a deterrent to herbivorous insects. Extractions specific to the leaf surface, the trichomes, and the laminar components demonstrated the localization of particular compounds. Diterpene glycosides occurred exclusively in leaf mesophyll, whereas nicotine was found in both the trichomes and mesophyll. Neither rutin nor nicotine was found on the leaf surface. Quercetin and 7 methylated derivatives were found in the glandular trichomes and appeared to be excreted onto the leaf surface. We examined the elicitation of these flavonols on the leaf surface with a surface-area allometric analysis, which measures changes in metabolites independent of the effects of leaf expansion. The flavonols responded differently to wounding, methyl jasmonate (MeJA), herbivore attack and UV-C radiation, and the response patterns corresponded to their compound-specific allometries. Finding greater amounts of quercetin on younger leaves and reduced amounts after herbivore feeding and MeJA treatment, we hypothesized that quercetin may function as an attractant, helping the insects locate a preferred feeding site. Consistent with this hypothesis, mirids (Tupiocoris notatus) were found more often on mature leaves sprayed with quercetin at a concentration typical of young leaves than on unsupplemented mature leaves. The composition of metabolites on the leaf surface of N. attenuata changes throughout leaf development and in response to herbivore attack or environmental stress, and these changes are mediated in part by responses of the glandular trichomes.

  17. Variants of glycoside hydrolases

    DOEpatents

    Teter, Sarah; Ward, Connie; Cherry, Joel; Jones, Aubrey; Harris, Paul; Yi, Jung

    2011-04-26

    The present invention relates to variants of a parent glycoside hydrolase, comprising a substitution at one or more positions corresponding to positions 21, 94, 157, 205, 206, 247, 337, 350, 373, 383, 438, 455, 467, and 486 of amino acids 1 to 513 of SEQ ID NO: 2, and optionally further comprising a substitution at one or more positions corresponding to positions 8, 22, 41, 49, 57, 113, 193, 196, 226, 227, 246, 251, 255, 259, 301, 356, 371, 411, and 462 of amino acids 1 to 513 of SEQ ID NO: 2 a substitution at one or more positions corresponding to positions 8, 22, 41, 49, 57, 113, 193, 196, 226, 227, 246, 251, 255, 259, 301, 356, 371, 411, and 462 of amino acids 1 to 513 of SEQ ID NO: 2, wherein the variants have glycoside hydrolase activity. The present invention also relates to nucleotide sequences encoding the variant glycoside hydrolases and to nucleic acid constructs, vectors, and host cells comprising the nucleotide sequences.

  18. Variants of glycoside hydrolases

    SciTech Connect

    Teter, Sarah; Ward, Connie; Cherry, Joel; Jones, Aubrey; Harris, Paul; Yi, Jung

    2013-02-26

    The present invention relates to variants of a parent glycoside hydrolase, comprising a substitution at one or more positions corresponding to positions 21, 94, 157, 205, 206, 247, 337, 350, 373, 383, 438, 455, 467, and 486 of amino acids 1 to 513 of SEQ ID NO: 2, and optionally further comprising a substitution at one or more positions corresponding to positions 8, 22, 41, 49, 57, 113, 193, 196, 226, 227, 246, 251, 255, 259, 301, 356, 371, 411, and 462 of amino acids 1 to 513 of SEQ ID NO: 2 a substitution at one or more positions corresponding to positions 8, 22, 41, 49, 57, 113, 193, 196, 226, 227, 246, 251, 255, 259, 301, 356, 371, 411, and 462 of amino acids 1 to 513 of SEQ ID NO: 2, wherein the variants have glycoside hydrolase activity. The present invention also relates to nucleotide sequences encoding the variant glycoside hydrolases and to nucleic acid constructs, vectors, and host cells comprising the nucleotide sequences.

  19. Acyl-acyl carrier protein: Lysomonogalactosyldiacylglycerol acyl transferase in Anabaena variabilis

    SciTech Connect

    Chen, H.H.

    1989-01-01

    Monogalactosyldiacylglycerol was produced when membranes isolated from the cyanobacterium, Anabaena variabilis, and washed free of soluble endogenous constituents, were incubated with ({sup 14}C)acyl-acyl carrier protein. This enzymatic synthesis of monogalactosyldiacylglycerol localized in the membranes was not dependent on any added cofactors, such as ATP, coenzyme A, and dithiothreitol. Palmitoyl-, stearoyl-, and oleoyl-acyl carrier proteins were approximately equally active as substrates with Km of 0.37, 0.36, and 0.23 {mu}M, respectively. The ({sup 14}C)acyl group was exclusively transferred to the sn-1 hydroxyl of the glycerol backbone of monogalactosyldiacylglycerol as demonstrated by hydrolysis of all incorporated acyl groups by the lipase from Rhizopus arrhizus delamar. Using a double labelled ({sup 14}C)acyl-({sup 14}C)acyl carrier protein, this enzyme catalyzed the direct transfer of the acyl group from acyl-acyl carrier protein to an endogenous lysomonogalactosyldiacylglycerol to form monogalactosyldiacylglycerol. The transfer reaction mechanism was also confirmed by the increased activity with the addition of the lysomonogalactosyldiacylglycerol suspension. A specific galactolipid acyl hydrolase activity was released into the soluble protein fraction when the membranes of Anabaena variabilis were treated with 2% Triton X-100. The positional specificity of this acyl hydrolase was demonstrated to be similar to that of Rhizopus lipase, i.e. only the acyl group at the sn-1 position was hydrolyzed. The acyl hydrolase which was also localized in the membrane fraction of Anabaena variabilis was presumably responsible for producing endogenous lysomonogalactosyldiacylglycerol used by the acyltransferase.

  20. Transgenic rice seed expressing flavonoid biosynthetic genes accumulate glycosylated and/or acylated flavonoids in protein bodies

    PubMed Central

    Ogo, Yuko; Mori, Tetsuya; Nakabayashi, Ryo; Saito, Kazuki; Takaiwa, Fumio

    2016-01-01

    Plant-specialized (or secondary) metabolites represent an important source of high-value chemicals. In order to generate a new production platform for these metabolites, an attempt was made to produce flavonoids in rice seeds. Metabolome analysis of these transgenic rice seeds using liquid chromatography-photodiode array-quadrupole time-of-flight mass spectrometry was performed. A total of 4392 peaks were detected in both transgenic and non-transgenic rice, 20–40% of which were only detected in transgenic rice. Among these, 82 flavonoids, including 37 flavonols, 11 isoflavones, and 34 flavones, were chemically assigned. Most of the flavonols and isoflavones were O-glycosylated, while many flavones were O-glycosylated and/or C-glycosylated. Several flavonoids were acylated with malonyl, feruloyl, acetyl, and coumaroyl groups. These glycosylated/acylated flavonoids are thought to have been biosynthesized by endogenous rice enzymes using newly synthesized flavonoids whose biosynthesis was catalysed by exogenous enzymes. The subcellular localization of the flavonoids differed depending on the class of aglycone and the glycosylation/acylation pattern. Therefore, flavonoids with the intended aglycones were efficiently produced in rice seeds via the exogenous enzymes introduced, while the flavonoids were variously glycosylated/acylated by endogenous enzymes. The results suggest that rice seeds are useful not only as a production platform for plant-specialized metabolites such as flavonoids but also as a tool for expanding the diversity of flavonoid structures, providing novel, physiologically active substances. PMID:26438413

  1. Dietary flavonoid and isoflavone glycosides are hydrolysed by the lactase site of lactase phlorizin hydrolase.

    PubMed

    Day, A J; Cañada, F J; Díaz, J C; Kroon, P A; Mclauchlan, R; Faulds, C B; Plumb, G W; Morgan, M R; Williamson, G

    2000-02-25

    Lactase phlorizin hydrolase (LPH; EC 3.2.1.62) is a membrane-bound, family 1 beta-glycosidase found on the brush border of the mammalian small intestine. LPH, purified from sheep small intestine, was capable of hydrolysing a range of flavonol and isoflavone glycosides. The catalytic efficiency (k(cat)/K(m)) for the hydrolysis of quercetin-4'-glucoside, quercetin-3-glucoside, genistein-7-glucoside and daidzein-7-glucoside was 170, 137, 77 and 14 (mM(-1) s(-1)) respectively. The majority of the activity occurred at the lactase and not phlorizin hydrolase site. The ability of LPH to deglycosylate dietary (iso)flavonoid glycosides suggests a possible role for this enzyme in the metabolism of these biologically active compounds.

  2. Glycoside vs. Aglycon: The Role of Glycosidic Residue in Biological Activity

    NASA Astrophysics Data System (ADS)

    Křen, Vladimír

    A large number of biologically active compounds are glycosides. Sometimes the glycosidic residue is crucial for their activity, in other cases glycosylation only improves pharmacokinetic parameters. Recent developments in molecular glycobiology brought better understanding of aglycon vs. glycoside activities, and made possible the development of new, more active or more effective glycodrugs based on these findings - a very illustrative recent example is vancomycin. The new enzymatic methodology "glycorandomization" enabled preparation of glycoside libraries and opened up paths to the preparation of optimized or entirely novel glycoside antibiotics. This chapter deals with an array of glycosidic compounds currently used in medicine but also covers the biological activity of some glycosidic metabolites of known drugs. The chapter discusses glycosides of vitamins, polyphenolic glycosides (flavonoids), alkaloid glycosides, glycosides of antibiotics, glycopeptides, cardiac glycosides, steroid and terpenoid glycosides etc. The physiological role of the glycosyl moiety and structure-activity relations (SAR) in the glycosidic moiety (-ies) are also discussed.

  3. Two new phenylpropanoid glycosides with interesterification from Scrophularia dentata Royle ex Benth

    NASA Astrophysics Data System (ADS)

    Zhang, Liuqiang; Yang, Zhuo; Jia, Qi; Dorje, Gaawe; Zhao, Zhili; Guo, Fujiang; Li, Yiming

    2013-10-01

    Two new phenylpropanoid glycosides (1-2), along with seven known ones (3-9), were isolated from the whole plant of Scrophularia dentata Royle ex Benth. Their structures were elucidated by spectroscopic methods. Among them, compounds 1 and 2 failed to separated, because they can easily transform into each other by acyl migrant reaction. In this paper, the interesterification mechanism was discussed firstly and the rule can be used in the similar structure elucidation in future.

  4. Differential stress-response expression of two flavonol synthase genes and accumulation of flavonols in tartary buckwheat.

    PubMed

    Li, Xiaohua; Kim, Yeon Bok; Kim, Yeji; Zhao, Shicheng; Kim, Haeng Hoon; Chung, Eunsook; Lee, Jai-Heon; Park, Sang Un

    2013-12-15

    Flavonoids are ubiquitously present in plants and play important roles in these organisms as well as in the human diet. Flavonol synthase (FLS) is a key enzyme of the flavonoid biosynthetic pathway, acting at the diverging point into the flavonol subclass branch. We isolated and characterized a FLS isoform gene, FtFLS2, from tartary buckwheat (Fagopyrum tataricum). FtFLS2 shares 48% identity and 67% similarity with the previously reported FtFLS1, whereas both genes share 47-65% identity and 65-69% similarity with FLSs from other plant species. Using quantitative real-time PCR and high-performance liquid chromatography (HPLC), the expression of FtFLS1/2 and the production of 3 main flavonols (kaempferol, myricetin and quercetin) was detected in roots, leaves, stems, flowers and different stages of developing seeds. The relationship between the expression of the 2 FLS genes and the accumulation of the 3 basic flavonols was analyzed in 2 tartary buckwheat cultivars. FtFLS1 and FtFLS2 exhibited differential transcriptional levels between the tartary buckwheat cultivars 'Hokkai T10' and 'Hokkai T8'. Generally, higher transcript levels of FtFLS1 and FtFLS2 and a higher amount of flavonols were observed in the 'Hokkai T10' cultivar than 'Hokkai T8'. The content of flavonols showed tissue-specific accumulation between the 2 cultivars. The transcription of FtFLS1 was inhibited by the exogenous application of abscisic acid (ABA), salicylic acid (SA) and sodium chloride (NaCl), while FtFLS2 was not affected by ABA but up-regulated by SA and NaCl. These data indicate that the 2 FtFLS isoforms of buckwheat have different functions in the response of buckwheat to environmental stress.

  5. A flavonoid 3-O-glucoside:2″-O-glucosyltransferase responsible for terminal modification of pollen-specific flavonols in Arabidopsis thaliana

    PubMed Central

    Yonekura-Sakakibara, Keiko; Nakabayashi, Ryo; Sugawara, Satoko; Tohge, Takayuki; Ito, Takuya; Koyanagi, Misuzu; Kitajima, Mariko; Takayama, Hiromitsu; Saito, Kazuki

    2014-01-01

    Flavonol 3-O-diglucosides with a 1→2 inter-glycosidic linkage are representative pollen-specific flavonols that are widely distributed in plants, but their biosynthetic genes and physiological roles are not well understood. Flavonoid analysis of four Arabidopsis floral organs (pistils, stamens, petals and calyxes) and flowers of wild-type and male sterility 1 (ms1) mutants, which are defective in normal development of pollen and tapetum, showed that kaempferol/quercetin 3-O-β-d-glucopyranosyl-(1→2)-β-d-glucopyranosides accumulated in Arabidopsis pollen. Microarray data using wild-type and ms1 mutants, gene expression patterns in various organs, and phylogenetic analysis of UDP-glycosyltransferases (UGTs) suggest that UGT79B6 (At5g54010) is a key modification enzyme for determining pollen-specific flavonol structure. Kaempferol and quercetin 3-O-glucosyl-(1→2)-glucosides were absent from two independent ugt79b6 knockout mutants. Transgenic ugt79b6 mutant lines transformed with the genomic UGT79B6 gene had the same flavonoid profile as wild-type plants. Recombinant UGT79B6 protein converted kaempferol 3-O-glucoside to kaempferol 3-O-glucosyl-(1→2)-glucoside. UGT79B6 recognized 3-O-glucosylated/galactosylated anthocyanins/flavonols but not 3,5- or 3,7-diglycosylated flavonoids, and prefers UDP-glucose, indicating that UGT79B6 encodes flavonoid 3-O-glucoside:2″-O-glucosyltransferase. A UGT79B6-GUS fusion showed that UGT79B6 was localized in tapetum cells and microspores of developing anthers. PMID:24916675

  6. New insights into the structure-cytotoxicity relationship of spirostan saponins and related glycosides.

    PubMed

    Pérez-Labrada, Karell; Brouard, Ignacio; Estévez, Sara; Marrero, María Teresa; Estévez, Francisco; Bermejo, Jaime; Rivera, Daniel G

    2012-04-15

    A variety of spirostan saponins and related glycosides were synthesized and evaluated for their cytotoxicity against the human myeloid leukemia cell line (HL-60). A linear glycosylation strategy allowed for accessing a variety of functionalization patterns at both the spirostanic and the saccharide moieties, which provides new information regarding the structure-cytotoxicity relationship of this family of steroidal glycosides. Intriguing results were achieved with respect to hecogenyl and 5α-hydroxy-laxogenyl β-chacotriosides, turning out to be the former very cytotoxic and the latter no cytotoxic at all. Importantly, the partially pivaloylated β-d-glucosides of 5α-hydroxy-laxogenin were the most potent cytotoxic compounds among all tested glycosides. This comprises the first report on acylated spirostanyl glucosides displaying significant cytotoxicity, and therefore, it opens up new opportunities toward the development of saponin analogues as anticancer agents. PMID:22405922

  7. Preparative isolation and purification of five flavonoid glycosides and one benzophenone galloyl glycoside from Psidium guajava by high-speed counter-current chromatography (HSCCC).

    PubMed

    Zhu, Yindi; Liu, Yue; Zhan, Ying; Liu, Lin; Xu, Yajuan; Xu, Tunhai; Liu, Tonghua

    2013-12-16

    Psidium guajava leaves have a diverse phytochemical composition including flavonoids, phenolics, meroterpenoids and triterpenes, responsible for the biological activities of the medicinal parts. In particular, flavonol glycosides show beneficial effects on type II diabetes mellitus. A simple and efficient HSCCC method has been developed for the preparative separation of five flavonoid glycosides and one diphenylmethane glycoside from P. guajava. A solvent system composed of n-hexane-ethyl acetate-methanol-water (0.7:4:0.8:4, v/v/v/v) was optimized for the separation. The upper phase was used as the stationary phase, and the lower phase was used as the mobile phase. Under the optimized conditions, hyperoside (15.3 mg), isoquercitrin (21.1 mg), reynoutrin (65.2 mg), quercetin-3-O-β-D-arabinopyranoside (71.7 mg), quercetin-3-O-α-L-arabinofuranoside (105.6 mg) and 2,4,6-trihydroxy-3,5-dimethylbenzophenone 4-O-(6''-O-galloyl)-β-D-glucopyranoside (98.4 mg) were separated from crude sample (19.8 g). The structures of all the isolates were identified by ESI-MS, 1H- and 13C-NMR analyses and their purities (>95%) were determined using HPLC.

  8. Acylation of Ferrocene: A Greener Approach

    ERIC Educational Resources Information Center

    Birdwhistell, Kurt R.; Nguyen, Andy; Ramos, Eric J.; Kobelja, Robert

    2008-01-01

    The acylation of ferrocene is a common reaction used in organic laboratories to demonstrate Friedel-Crafts acylation and the purification of compounds using column chromatography. This article describes an acylation of ferrocene experiment that is more eco-friendly than the conventional acylation experiment. The traditional experiment was modified…

  9. Acylation of Streptomyces type II polyketide synthase acyl carrier proteins.

    PubMed

    Crosby, J; Byrom, K J; Hitchman, T S; Cox, R J; Crump, M P; Findlow, I S; Bibb, M J; Simpson, T J

    1998-08-14

    Acyl derivatives of type II PKS ACPs are required for in vitro studies of polyketide biosynthesis. The presence of an exposed cysteine residue prevented specific chemical acylation of the phosphopantetheine thiol of the actinorhodin PKS holo ACP. Acylation studies were further complicated by intramolecular disulphide formation between cysteine 17 and the phosphopantetheine. The presence of this intramolecular disulphide was confirmed by tryptic digestion of the ACP followed by ESMS analysis of the fragments. An act Cys17Ser ACP was engineered by site-directed mutagenesis. S-Acyl adducts of act C17S, oxytetracycline and griseusin holo ACPs were rapidly formed by reaction with hexanoyl, 5-ketohexanoyl and protected acetoacetyl imidazolides. Comparisons with type 11 FAS ACPs were made.

  10. Anti-androgenic effects of flavonols in prostate cancer

    PubMed Central

    Boam, Tristan

    2015-01-01

    Dietary-derived agents, such as the flavonoids, are of particular interest for prostate cancer (PCa) chemoprevention as they may offer a favourable safety and side-effect profile. An agent that demonstrates action on the androgen receptor (AR) axis may have value for preventing or treating castrate-resistant PCa. Four main flavonols – quercetin, myricetin, kaempferol, and fisetin – have been demonstrated in laboratory studies to have chemopreventive action in both castrate-resistant and castrate-sensitive PCa models. Mechanisms of flavonol action on the AR axis in PCa have been proposed to be inhibition of the 5α-reductase enzymes, direct androgen competition, suppression of the AR complex and transactivation by coregulators such as c-Jun, Sp1, and the PI3K/Akt pathway. It is, however, still unclear with current levels of evidence whether AR axis-mediated effects can fully account for the flavonols’ chemopreventive action. PMID:26557883

  11. Evaluation of flavonols and derivatives as human cathepsin B inhibitor.

    PubMed

    Ramalho, Suelem D; de Sousa, Lorena R F; Burger, Marcela C M; Lima, Maria Inês S; da Silva, M Fátima das G F; Fernandes, João B; Vieira, Paulo C

    2015-01-01

    Cathepsin B (catB) is a cysteine protease involved in tumour progression and represents a potential therapeutic target in cancer. Among the 15 evaluated extracts from cerrado biome, Myrcia lingua Berg. (Myrtaceae) extract demonstrated to be a source of compounds with potential to inhibit catB. Using bioactivity-guided fractionation, we have found flavonols as inhibitors and also some other derivatives were obtained. From the evaluated compounds, myricetin (5) and quercetin (6) showed the most promising results with IC50 of 4.9 and 8.2 μM, respectively, and mode of inhibition as uncompetitive on catB. The results demonstrated polyhydroxylated flavonols as promising inhibitors of catB. PMID:25622620

  12. Evolution of Acyl-Substrate Recognition by a Family of Acyl-Homoserine Lactone Synthases

    PubMed Central

    Christensen, Quin H.; Brecht, Ryan M.; Dudekula, Dastagiri; Greenberg, E. Peter; Nagarajan, Rajesh

    2014-01-01

    Members of the LuxI protein family catalyze synthesis of acyl-homoserine lactone (acyl-HSL) quorum sensing signals from S-adenosyl-L-methionine and an acyl thioester. Some LuxI family members prefer acyl-CoA, and others prefer acyl-acyl carrier protein (ACP) as the acyl-thioester substrate. We sought to understand the evolutionary history and mechanisms mediating this substrate preference. Our phylogenetic and motif analysis of the LuxI acyl-HSL synthase family indicates that the acyl-CoA-utilizing enzymes evolved from an acyl-ACP-utilizing ancestor. To further understand how acyl-ACPs and acyl-CoAs are recognized by acyl-HSL synthases we studied BmaI1, an octanoyl-ACP-dependent LuxI family member from Burkholderia mallei, and BjaI, an isovaleryl-CoA-dependent LuxI family member from Bradyrhizobium japonicum. We synthesized thioether analogs of their thioester acyl-substrates to probe recognition of the acyl-phosphopantetheine moiety common to both acyl-ACP and acyl-CoA substrates. The kinetics of catalysis and inhibition of these enzymes indicate that they recognize the acyl-phosphopantetheine moiety and they recognize non-preferred substrates with this moiety. We find that CoA substrate utilization arose through exaptation of acyl-phosphopantetheine recognition in this enzyme family. PMID:25401334

  13. [Study of degradation of flavonols in the mutants of poppy (Papaver somniferum L.)].

    PubMed

    Rat'kin, A V; Evdokimova, L I; Zhanaeva, T A

    2003-01-01

    We studied flavonol-degrading activity of cell-free extracts from petals of the flower color and structure mutants. The relationship between degradation of flavonols (kaempferol, quercetin, and myricetin) and biosynthesis of anthocyanins has been revealed. The highest flavonol-degrading activity has been revealed in white flower mutants towards all substrates, particularly, quercetin. The mutations inhibiting synthesis of an anthocyanin pelargonidin provide for synthesis of various quantities of cyanidin in the petals. The flavonol-degrading activity considerably increases with the content of cyanidin. A similar relationship has been revealed in the mutants synthesizing both cyanidin and pelargonidin. The plants accumulating considerable quantities of pelargonidin in their petals have accordingly higher flavonol-degrading activity and predominantly hydrolyze kaempferol. The plants forming additional pods in their flower (pistillody) have higher flavonol-degrading activity as compared to the anther-in-petal and doubleness mutants.

  14. Biginkgosides A-I, Unexpected Minor Dimeric Flavonol Diglycosidic Truxinate and Truxillate Esters from Ginkgo biloba Leaves and Their Antineuroinflammatory and Neuroprotective Activities.

    PubMed

    Ma, Guang-Lei; Xiong, Juan; Yang, Guo-Xun; Pan, Li-Long; Hu, Chang-Ling; Wang, Wei; Fan, Hui; Zhao, Qiu-Hua; Zhang, Hai-Yan; Hu, Jin-Feng

    2016-05-27

    Nine unexpected new flavonol glycoside cyclodimers in the truxinate (1-7, biginkgosides A-G, respectively) or truxillate [biginkgosides H (8) and I (9)] forms were isolated as minor components from the extract of Ginkgo biloba leaves. The new dimers possess an unusual cyclobutane ring formed by a [2+2]-cycloaddition between two symmetric (for compounds 1-5 and 7-9) or nonsymmetric (for 6) flavonol coumaroyl glucorhamnosides. A plausible biosynthetic pathway for these new compounds based on the frontier molecular orbital theory of cycloaddition reactions is briefly discussed. An antineuroinflammatory screening revealed that biginkgosides E (5) and H (8) inhibited nitric oxide production in lipopolysaccharide-activated BV-2 microglial cells, with IC50 values of 2.91 and 17.23 μM, respectively. Additionally, biginkgoside F (6) showed a significant neuroprotective effect (34.3% increase in cell viability at 1 μM) against Aβ25-35-induced cell viability decrease in SH-SY5Y neuroblastoma cells. PMID:27140807

  15. Effects of flavonol-rich green tea cultivar (Camellia sinensis L.) on plasma oxidized LDL levels in hypercholesterolemic mice.

    PubMed

    Nomura, Sachiko; Monobe, Manami; Ema, Kaori; Matsunaga, Akiko; Maeda-Yamamoto, Mari; Horie, Hideki

    2016-01-01

    To examine the possible benefits of tea flavonols, we compared anti-atherogenic effects between common and flavonol-rich tea cultivars. The tea infusion made from a flavonol-rich cultivar, but not a common cultivar, significantly decreased the plasma oxidized low-density lipoprotein level in mice fed a high-cholesterol diet. The result suggests that tea flavonols have the potential to protect against cardiovascular diseases.

  16. Effects of flavonol-rich green tea cultivar (Camellia sinensis L.) on plasma oxidized LDL levels in hypercholesterolemic mice.

    PubMed

    Nomura, Sachiko; Monobe, Manami; Ema, Kaori; Matsunaga, Akiko; Maeda-Yamamoto, Mari; Horie, Hideki

    2016-01-01

    To examine the possible benefits of tea flavonols, we compared anti-atherogenic effects between common and flavonol-rich tea cultivars. The tea infusion made from a flavonol-rich cultivar, but not a common cultivar, significantly decreased the plasma oxidized low-density lipoprotein level in mice fed a high-cholesterol diet. The result suggests that tea flavonols have the potential to protect against cardiovascular diseases. PMID:26364623

  17. Ethylene-induced flavonol accumulation in guard cells suppresses reactive oxygen species and moderates stomatal aperture.

    PubMed

    Watkins, Justin M; Hechler, Paul J; Muday, Gloria K

    2014-04-01

    Guard cell swelling controls the aperture of stomata, pores that facilitate gas exchange and water loss from leaves. The hormone abscisic acid (ABA) has a central role in regulation of stomatal closure through synthesis of second messengers, which include reactive oxygen species (ROS). ROS accumulation must be minimized by antioxidants to keep concentrations from reaching damaging levels within the cell. Flavonols are plant metabolites that have been implicated as antioxidants; however, their antioxidant activity in planta has been debated. Flavonols accumulate in guard cells of Arabidopsis thaliana, but not surrounding pavement cells, as visualized with a flavonol-specific dye. The expression of a reporter driven by the promoter of CHALCONE SYNTHASE, a gene encoding a flavonol biosynthetic enzyme, in guard cells, but not pavement cells, suggests guard cell-specific flavonoid synthesis. Increased levels of ROS were detected using a fluorescent ROS sensor in guard cells of transparent testa4-2, which has a null mutation in CHALCONE SYNTHASE and therefore synthesizes no flavonol antioxidants. Guard cells of transparent testa4-2 show more rapid ABA-induced closure than the wild type, suggesting that flavonols may dampen the ABA-dependent ROS burst that drives stomatal closing. The levels of flavonols are positively regulated in guard cells by ethylene treatment in the wild type, but not in the ethylene-insensitive2-5 mutant. In addition, in both ethylene-overproducing1 and ethylene-treated wild-type plants, elevated flavonols lead to decreasing ROS and slower ABA-mediated stomatal closure. These results are consistent with flavonols suppressing ROS accumulation and decreasing the rate of ABA-dependent stomatal closure, with ethylene-induced increases in guard cell flavonols modulating these responses.

  18. Triterpenoid glycosides from Bacopa monnieri.

    PubMed

    Sivaramakrishna, Chillara; Rao, Chirravuri V; Trimurtulu, Golakoti; Vanisree, Mulabagal; Subbaraju, Gottumukkala V

    2005-12-01

    Two triterpenoid glycosides have been isolated along with 10 known saponins from Bacopa monnieri. Structures of the compounds have been elucidated as 3-O-[beta-D-glucopyranosyl-(1-->3)-beta-D-glucopyranosyl] jujubogenin (1) and 3-O-[beta-D-glucopyranosyl-(1-->3)-beta-D-glucopyranosyl] pseudojujubogenin (2) by high resolution NMR spectral data and chemical correlations. Further, the chemical compositions of bacosides A and B have been delineated.

  19. Iridoid glycosides from Gmelina arborea.

    PubMed

    Tiwari, Neerja; Yadav, Akhilesh K; Srivastava, Pooja; Shanker, Karuna; Verma, Ram K; Gupta, Madan M

    2008-09-01

    Three iridoid glycosides 6-O-(3''-O-benzoyl)-alpha-L-rhamnopyranosylcatalpol (1a), 6-O-(3''-O-trans-cinnamoyl)-alpha-L-rhamnopyranosylcatalpol (2a) and 6-O-(3''-O-cis-cinnamoyl)-alpha-L-rhamnopyranosylcatalpol (3a) were isolated from aerial parts of Gmelina arborea and structures were elucidated by spectral analysis. Additionally a known iridoid 6-O-(3'', 4''-O-dibenzoyl)-alpha-L-rhamnopyranosylcatalpol (4) was also isolated and identified. PMID:18684476

  20. Bioconversion of steroid glycosides by Nocardia restricta.

    PubMed

    Belic, I; Kastelic-Suhadolc, T; Kralj, B

    1985-09-01

    The bioconversion of steroid alkaloid tomatine by Nocardia restricta yields the conjugate with lactic acid. We studied the bioconversion of some steroid glycosides without a nitrogen atom in the molecule to determine the effect of the nitrogen atom. The glycosides were of three different types: sterol glycosides, bufadienolide rhamnoside and steroid saponine. The results of bioconversions showed that Nocardia restricta converts steroid glycosides differently according to the sugar bound to the steroid aglycone. It can be concluded that in the absence of a nitrogen atom in the steroid molecule no conjugation with lactic acid by Nocardia restricta occurs. PMID:4046605

  1. Lipoxygenase-inhibiting phenolic glycosides and monoterpene glycosides from Paeonia lactiflora.

    PubMed

    Zou, Liang; Hu, Lin-Feng; Guo, Yi-Dong; Song, Yu; Fu, Qiang

    2015-01-01

    The EtOH extract of the roots of Paeonia lactiflora afforded a new phenolic glycoside paenoside A (1) and a new monoterpene glycoside paeonin D (2), and five known monoterpene glycosides. Their structures were elucidated on the basis of spectroscopic means and hydrolysis products. All compounds displayed inhibitory potential against enzyme lipoxygenase.

  2. Lipoxygenase-inhibiting phenolic glycosides and monoterpene glycosides from Paeonia lactiflora.

    PubMed

    Zou, Liang; Hu, Lin-Feng; Guo, Yi-Dong; Song, Yu; Fu, Qiang

    2015-01-01

    The EtOH extract of the roots of Paeonia lactiflora afforded a new phenolic glycoside paenoside A (1) and a new monoterpene glycoside paeonin D (2), and five known monoterpene glycosides. Their structures were elucidated on the basis of spectroscopic means and hydrolysis products. All compounds displayed inhibitory potential against enzyme lipoxygenase. PMID:25798791

  3. Flavonols (kaempeferol, quercetin, myricetin) contents of selected fruits, vegetables and medicinal plants.

    PubMed

    Sultana, Bushra; Anwar, Farooq

    2008-06-01

    The concentrations of flavonols (kaempeferol, quercetin, myricetin) were determined in 22 plant materials (9 vegetables, 5 fruits, and 8 medicinal plant organs). The materials were extracted with acidified methanol (methanol/HCl, 100:1, v/v) and analyzed by reverse phase high-performance liquid chromatographic (RP-HPLC) with UV detection. The total flavonols contents varied significantly (P<0.05) among vegetables, fruits and medicinal plant organs ranged from 0 to 1720.5, 459.9 to 3575.4, and 2.42 to 6125.6mgkg(-1) of dry matter, respectively. Among vegetables, spinach and cauliflower exhibited the highest amounts of flavonols (1720.5 and 1603.9mgkg(-1), respectively), however, no flavonols were detected in garlic. Within fruits, highest level of flavonols was observed in strawberry (3575.4mgkg(-1)), whereas, the lowest in apple fruit (459.9mgkg(-1)). Of the medicinal plant organs, moringa and aloe vera leaves contained the highest contents of flavonols (6125.6 and 1636.04mgkg(-1)), respectively, whereas, lowest was present in barks (2.42-274.07mgkg(-1)). Overall, leafy green vegetables, soft fruits and medicinal plant leaves exhibited higher levels of flavonols.

  4. Flavonols Mediate Root Phototropism and Growth through Regulation of Proliferation-to-Differentiation Transition.

    PubMed

    Silva-Navas, Javier; Moreno-Risueno, Miguel A; Manzano, Concepción; Téllez-Robledo, Bárbara; Navarro-Neila, Sara; Carrasco, Víctor; Pollmann, Stephan; Gallego, F Javier; Del Pozo, Juan C

    2016-06-01

    Roots normally grow in darkness, but they may be exposed to light. After perceiving light, roots bend to escape from light (root light avoidance) and reduce their growth. How root light avoidance responses are regulated is not well understood. Here, we show that illumination induces the accumulation of flavonols in Arabidopsis thaliana roots. During root illumination, flavonols rapidly accumulate at the side closer to light in the transition zone. This accumulation promotes asymmetrical cell elongation and causes differential growth between the two sides, leading to root bending. Furthermore, roots illuminated for a long period of time accumulate high levels of flavonols. This high flavonol content decreases both auxin signaling and PLETHORA gradient as well as superoxide radical content, resulting in reduction of cell proliferation. In addition, cytokinin and hydrogen peroxide, which promote root differentiation, induce flavonol accumulation in the root transition zone. As an outcome of prolonged light exposure and flavonol accumulation, root growth is reduced and a different root developmental zonation is established. Finally, we observed that these differentiation-related pathways are required for root light avoidance. We propose that flavonols function as positional signals, integrating hormonal and reactive oxygen species pathways to regulate root growth direction and rate in response to light.

  5. Flavonols Mediate Root Phototropism and Growth through Regulation of Proliferation-to-Differentiation Transition.

    PubMed

    Silva-Navas, Javier; Moreno-Risueno, Miguel A; Manzano, Concepción; Téllez-Robledo, Bárbara; Navarro-Neila, Sara; Carrasco, Víctor; Pollmann, Stephan; Gallego, F Javier; Del Pozo, Juan C

    2016-06-01

    Roots normally grow in darkness, but they may be exposed to light. After perceiving light, roots bend to escape from light (root light avoidance) and reduce their growth. How root light avoidance responses are regulated is not well understood. Here, we show that illumination induces the accumulation of flavonols in Arabidopsis thaliana roots. During root illumination, flavonols rapidly accumulate at the side closer to light in the transition zone. This accumulation promotes asymmetrical cell elongation and causes differential growth between the two sides, leading to root bending. Furthermore, roots illuminated for a long period of time accumulate high levels of flavonols. This high flavonol content decreases both auxin signaling and PLETHORA gradient as well as superoxide radical content, resulting in reduction of cell proliferation. In addition, cytokinin and hydrogen peroxide, which promote root differentiation, induce flavonol accumulation in the root transition zone. As an outcome of prolonged light exposure and flavonol accumulation, root growth is reduced and a different root developmental zonation is established. Finally, we observed that these differentiation-related pathways are required for root light avoidance. We propose that flavonols function as positional signals, integrating hormonal and reactive oxygen species pathways to regulate root growth direction and rate in response to light. PMID:26628743

  6. Modified acyl-ACP desaturase

    DOEpatents

    Cahoon, Edgar B.; Shanklin, John; Lindgvist, Ylva; Schneider, Gunter

    1998-01-06

    Disclosed is a methods for modifying the chain length and double bond positional specificities of a soluble plant fatty acid desaturase. More specifically, the method involves modifying amino acid contact residues in the substrate binding channel of the soluble fatty acid desaturase which contact the fatty acid. Specifically disclosed is the modification of an acyl-ACP desaturase. Amino acid contact residues which lie within the substrate binding channel are identified, and subsequently replaced with different residues to effect the modification of activity.

  7. Modified Acyl-ACP desaturase

    DOEpatents

    Cahoon, Edgar B.; Shanklin, John; Lindqvist, Ylva; Schneider, Gunter

    1999-03-30

    Disclosed is a method for modifying the chain length and double bond positional specificities of a soluble plant fatty acid desaturase. More specifically, the method involves modifying amino acid contact residues in the substrate binding channel of the soluble fatty acid desaturase which contact the fatty acid. Specifically disclosed is the modification of an acyl-ACP desaturase. Amino acid contact residues which lie within the substrate binding channel are identified, and subsequently replaced with different residues to effect the modification of activity.

  8. Stearoyl-Acyl Carrier Protein and Unusual Acyl-Acyl Carrier Protein Desaturase Activities Are Differentially Influenced by Ferredoxin1

    PubMed Central

    Schultz, David J.; Suh, Mi Chung; Ohlrogge, John B.

    2000-01-01

    Acyl-acyl carrier protein (ACP) desaturases function to position a single double bond into an acyl-ACP substrate and are best represented by the ubiquitous Δ9 18:0-ACP desaturase. Several variant acyl-ACP desaturases have also been identified from species that produce unusual monoenoic fatty acids. All known acyl-ACP desaturase enzymes use ferredoxin as the electron-donating cofactor, and in almost all previous studies the photosynthetic form of ferredoxin rather than the non-photosynthetic form has been used to assess activity. We have examined the influence of different forms of ferredoxin on acyl-ACP desaturases. Using combinations of in vitro acyl-ACP desaturase assays and [14C]malonyl-coenzyme A labeling studies, we have determined that heterotrophic ferredoxin isoforms support up to 20-fold higher unusual acyl-ACP desaturase activity in coriander (Coriandrum sativum), Thunbergia alata, and garden geranium (Pelargonium × hortorum) when compared with photosynthetic ferredoxin isoforms. Heterotrophic ferredoxin also increases activity of the ubiquitous Δ9 18:0-ACP desaturase 1.5- to 3.0-fold in both seed and leaf extracts. These results suggest that ferredoxin isoforms may specifically interact with acyl-ACP desaturases to achieve optimal enzyme activity and that heterotrophic isoforms of ferredoxin may be the in vivo electron donor for this reaction. PMID:11027717

  9. Two New Triterpene Glycosides from Centella asiatica

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Phytochemical investigation of the leaves of Centella asiatica resulted in the isolation and characterization of one new ursane type triterpene glycoside; asiaticoside G along with nine known compounds, that were characterized as ursane type triterpenes and /or their glycoside; asiatic acid (2), mad...

  10. The Physiology of Protein S-acylation

    PubMed Central

    Chamberlain, Luke H.; Shipston, Michael J.

    2015-01-01

    Protein S-acylation, the only fully reversible posttranslational lipid modification of proteins, is emerging as a ubiquitous mechanism to control the properties and function of a diverse array of proteins and consequently physiological processes. S-acylation results from the enzymatic addition of long-chain lipids, most typically palmitate, onto intracellular cysteine residues of soluble and transmembrane proteins via a labile thioester linkage. Addition of lipid results in increases in protein hydrophobicity that can impact on protein structure, assembly, maturation, trafficking, and function. The recent explosion in global S-acylation (palmitoyl) proteomic profiling as a result of improved biochemical tools to assay S-acylation, in conjunction with the recent identification of enzymes that control protein S-acylation and de-acylation, has opened a new vista into the physiological function of S-acylation. This review introduces key features of S-acylation and tools to interrogate this process, and highlights the eclectic array of proteins regulated including membrane receptors, ion channels and transporters, enzymes and kinases, signaling adapters and chaperones, cell adhesion, and structural proteins. We highlight recent findings correlating disruption of S-acylation to pathophysiology and disease and discuss some of the major challenges and opportunities in this rapidly expanding field. PMID:25834228

  11. Development of Marker-Free Transgenic Potato Tubers Enriched in Caffeoylquinic Acids and Flavonols.

    PubMed

    Li, Yang; Tang, Wenzhao; Chen, Jing; Jia, Ru; Ma, Lianjie; Wang, Shaoli; Wang, Jiao; Shen, Xiangling; Chu, Zhaohui; Zhu, Changxiang; Ding, Xinhua

    2016-04-13

    Potato (Solanum tuberosum L.) is a major crop worldwide that meets human economic and nutritional requirements. Potato has several advantages over other crops: easy to cultivate and store, cheap to consume, and rich in a variety of secondary metabolites. In this study, we generated three marker-free transgenic potato lines that expressed the Arabidopsis thaliana flavonol-specific transcriptional activator AtMYB12 driven by the tuber-specific promoter Patatin. Marker-free potato tubers displayed increased amounts of caffeoylquinic acids (CQAs) (3.35-fold increases on average) and flavonols (4.50-fold increase on average). Concentrations of these metabolites were associated with the enhanced expression of genes in the CQA and flavonol biosynthesis pathways. Accumulation of CQAs and flavonols resulted in 2-fold higher antioxidant capacity compared to wild-type potatoes. Tubers from these marker-free transgenic potatoes have therefore improved antioxidant properties. PMID:27019017

  12. Impact of different stages of juice processing on the anthocyanin, flavonol, and procyanidin contents of cranberries.

    PubMed

    White, Brittany L; Howard, Luke R; Prior, Ronald L

    2011-05-11

    Juice is the most common form in which cranberries are consumed; however there is limited information on the changes of polyphenolic content of the berries during juice processing. This study investigated the effects of three different pretreatments (grinding plus blanching; only grinding; only blanching) for cranberry juice processing on the concentrations of anthocyanins, flavonols, and procyanidins throughout processing. Flavonols and procyanidins were retained in the juice to a greater extent than anthocyanins, and pressing resulted in the most significant losses in polyphenolics due to removal of the seeds and skins. Flavonol aglycones were formed during processing as a result of heat treatment. Drying of cranberry pomace resulted in increased extraction of flavonols and procyanidin oligomers but lower extraction of polymeric procyanidins. The results indicate that cranberry polyphenolics are relatively stable during processing compared to other berries; however, more work is needed to determine their fate during storage of juices.

  13. Influence of derivation on the lipophilicity and inhibitory actions of cardiac glycosides on myocardial Na+-K+-ATPase.

    PubMed Central

    Dzimiri, N.; Fricke, U.; Klaus, W.

    1987-01-01

    Lipophilicity and inhibitory actions on guinea-pig heart Na+-K+-ATPase of twenty-six digitalis and six strophanthus glycosides comprising the aglycones, mono-, bis-, tris-sugar, alkylated (acylated) tris-sugar, acyl steroid derivatives and three cardanolides were investigated. Their octanol/water partition coefficients (P), reversed phase thin layer (r.t.l.c.) and reversed phase high performance liquid chromatography (r.h.p.l.c.) were determined and the viability of these methods as a measure of the lipophilicity of the cardiotonic steroids evaluated. The influence of lipophilicity and so also structural changes on the inhibitory effects of the cardiac glycosides on myocardial Na+-K+-ATPase was then examined. It is concluded that (a) r.t.l.c. and r.h.p.l.c. are just as effective as the conventional shake-flask method for estimation of the lipophilicity of cardiac glycosides and (b) the inhibitory potencies of cardiotonic steroids on the myocardial Na+-K+-ATPase increase with growing lipophilicity. The relationship between these two parameters is, however, governed by the influence of substitution or derivation of structural components on their inhibitory potencies on the myocardial Na+-K+-ATPase. PMID:3036289

  14. Topology and acylation of spiralin.

    PubMed Central

    Wróblewski, H; Nyström, S; Blanchard, A; Wieslander, A

    1989-01-01

    Of the 51 polypeptides detected by sodium dodecyl sulfate-polyacrylamide gel electrophoresis in the plasma membrane of the helical mollicute Spiroplasma melliferum, 21 are acylated, predominantly with myristic (14:0) and palmitic (16:0) chains. This is notably the case for spiralin, the major membrane protein of this bacterium, which contains an average of 0.7 acyl chains per polypeptide, attached very probably by ester bonds to alcohol amino acids. The amphiphilicity of spiralin was demonstrated by the behavior of the protein in charge-shift electrophoresis, its incorporation into liposomes, and its ability to form in the absence of lipids and detergents, globular protein micelles (diameter, approximately 15 nm). The presence of epitopes on the two faces of the cell membrane, as probed by antibody adsorption and crossed immunoelectrophoresis, and the strong interaction between spiralin and the intracytoplasmic fibrils show that spiralin is a transmembrane protein. The mean hydropathy of the amino acid composition of spiralin (-0.30) is on the hydrophilic side of the scale. Surprisingly, the water-insoluble core of spiralin micelles, which is the putative membrane anchor, has a still more hydrophilic amino acid composition (mean hydropathy, -0.70) and is enriched in glycine and serine residues. Taking into account all these properties, we propose a topological model for spiralin featuring a transbilayer localization with hydrophilic domains protruding on the two faces of the membrane and connected by a small domain embedded within the apolar region of the lipid bilayer. In this model, the membrane anchoring of the protein is strengthened by a covalently bound acyl chain. Images PMID:2768198

  15. Versatility of acyl-acyl carrier protein synthetases.

    PubMed

    Beld, Joris; Finzel, Kara; Burkart, Michael D

    2014-10-23

    The acyl carrier protein (ACP) requires posttranslational modification with a 4'-phosphopantetheine arm for activity, and this thiol-terminated modification carries cargo between enzymes in ACP-dependent metabolic pathways. We show that acyl-ACP synthetases (AasSs) from different organisms are able to load even, odd, and unnatural fatty acids onto E. coli ACP in vitro. Vibrio harveyi AasS not only shows promiscuity for the acid substrate, but also is active upon various alternate carrier proteins. AasS activity also extends to functional activation in living organisms. We show that exogenously supplied carboxylic acids are loaded onto ACP and extended by the E. coli fatty acid synthase, including unnatural fatty acid analogs. These analogs are further integrated into cellular lipids. In vitro characterization of four different adenylate-forming enzymes allowed us to disambiguate CoA-ligases and AasSs, and further in vivo studies show the potential for functional application in other organisms. PMID:25308274

  16. Neuroprotective actions of flavones and flavonols: mechanisms and relationship to flavonoid structural features.

    PubMed

    Dajas, Federico; Andrés, Abin-Carriquiry Juan; Florencia, Arredondo; Carolina, Echeverry; Felicia, Rivera-Megret

    2013-03-01

    Epidemiological studies have shown positive preventive action of flavonoids on cardiovascular and neurodegenerative events. Among the six groups in which flavonoids are classified, the flavones and flavonols, based on the backbone of 2-phenylchromen-4-one (2-phenyl-1-benzopyran-4-one) are the most commonly encountered within the families and genera of the higher plants. Numerous studies support a neuroprotective activity of flavones such as luteolin and flavonols such as kaempherol and quercetin in experimental focal ischemia and models of neurodegeneration. Antioxidation, modulation of signaling cascades and gene expression as well as anti-inflammation appear as the main protective mechanisms and mitochondria are a likely main target mediating the preventive actions against oxidative stress. Flavones and flavonols re-establish the redox regulation of proteins, transcription factors and signaling cascades that are otherwise inhibited by elevated oxidative stress. The final survival or death of the neuron depends on flavone and flavonol concentrations, time of exposure and, mainly, metabolic and oxidative neuronal circumstances. Neuroprotection appears to be linked to specific structural motifs, beyond those involved in antioxidation. By themselves or as templates for synthetic compounds, flavone and flavonol molecules show potential as multi-targeted therapeutic tools for protecting the brain. Nonetheless, more research needs to be done on the correlation of potential beneficial effects of flavones and flavonols and their mechanisms of action. PMID:23092407

  17. Neuroprotective actions of flavones and flavonols: mechanisms and relationship to flavonoid structural features.

    PubMed

    Dajas, Federico; Andrés, Abin-Carriquiry Juan; Florencia, Arredondo; Carolina, Echeverry; Felicia, Rivera-Megret

    2013-03-01

    Epidemiological studies have shown positive preventive action of flavonoids on cardiovascular and neurodegenerative events. Among the six groups in which flavonoids are classified, the flavones and flavonols, based on the backbone of 2-phenylchromen-4-one (2-phenyl-1-benzopyran-4-one) are the most commonly encountered within the families and genera of the higher plants. Numerous studies support a neuroprotective activity of flavones such as luteolin and flavonols such as kaempherol and quercetin in experimental focal ischemia and models of neurodegeneration. Antioxidation, modulation of signaling cascades and gene expression as well as anti-inflammation appear as the main protective mechanisms and mitochondria are a likely main target mediating the preventive actions against oxidative stress. Flavones and flavonols re-establish the redox regulation of proteins, transcription factors and signaling cascades that are otherwise inhibited by elevated oxidative stress. The final survival or death of the neuron depends on flavone and flavonol concentrations, time of exposure and, mainly, metabolic and oxidative neuronal circumstances. Neuroprotection appears to be linked to specific structural motifs, beyond those involved in antioxidation. By themselves or as templates for synthetic compounds, flavone and flavonol molecules show potential as multi-targeted therapeutic tools for protecting the brain. Nonetheless, more research needs to be done on the correlation of potential beneficial effects of flavones and flavonols and their mechanisms of action.

  18. [Variability of flavonol contents during floral morphogenesis in Papaver somniferum L].

    PubMed

    Beliaeva, R G; Evdokimova, L I

    2004-01-01

    We studied the contents of flavonols (kaempferol and quercetin) in the meristem of vegetative and generative apices of the main plant shoot in floral Papaver somniferum mutants, as well as in the normal plants at successive stages of flower development. Five stages of flower development were distinguished. Flavonols (kaempferol and quercetin) were present in all flower organs at all stages of floral morphogenesis we studied. However, their contents and distribution in different organs and at different stages of flower development markedly varied. No significant differences were found in the contents of flavonols in the meristems of vegetative and generative apices of the main shoot in the lines of floral mutants, as well as between the lines with different amounts of vegetative phytomeres. In the plants with normal flower structure, the contents of flavonols (kaempferol + quercetin) sharply increased with the beginning of differentiation of flower organs, i.e. from stage 3, to reach a maximum in the open flower, when gametogenesis is terminated and fertilization takes place. The level of flavonol contents in the petals (upper part) and stamen was at a maximum at all stages of flower development, while that in the gynaecium was at a minimum. The kaempferol: quercetin ratio shifted towards quercetin at successive stages of flower development, most significantly in the stamens. The involvement of flavonols in the regulation of floral morphogenesis at stages of flower organs differentiation and functioning is discussed.

  19. Modified Acyl-ACP desaturase

    DOEpatents

    Cahoon, E.B.; Shanklin, J.; Lindqvist, Y.; Schneider, G.

    1999-03-30

    Disclosed is a method for modifying the chain length and double bond positional specificities of a soluble plant fatty acid desaturase. More specifically, the method involves modifying amino acid contact residues in the substrate binding channel of the soluble fatty acid desaturase which contact the fatty acid. Specifically disclosed is the modification of an acyl-ACP desaturase. Amino acid contact residues which lie within the substrate binding channel are identified, and subsequently replaced with different residues to effect the modification of activity. 2 figs.

  20. Modified acyl-ACP desaturase

    DOEpatents

    Cahoon, E.B.; Shanklin, J.; Lindgvist, Y.; Schneider, G.

    1998-01-06

    Disclosed is a method for modifying the chain length and double bond positional specificities of a soluble plant fatty acid desaturase. More specifically, the method involves modifying amino acid contact residues in the substrate binding channel of the soluble fatty acid desaturase which contact the fatty acid. Specifically disclosed is the modification of an acyl-ACP desaturase. Amino acid contact residues which lie within the substrate binding channel are identified, and subsequently replaced with different residues to effect the modification of activity. 1 fig.

  1. The Passiflora tripartita (Banana Passion) fruit: a source of bioactive flavonoid C-glycosides isolated by HSCCC and characterized by HPLC–DAD–ESI/MS/MS.

    PubMed

    Simirgiotis, Mario J; Schmeda-Hirschmann, Guillermo; Bórquez, Jorge; Kennelly, Edward J

    2013-01-01

    The banana passion fruit (Passiflora tripartita Breiter, Passifloraceae) known as "tumbo" is very appreciated in tropical and subtropical countries of South America. Methanolic extracts from peel and the fruit juice of P. tripartita growing in Chile were analyzed for antioxidant capacity as well as for flavonoid and phenolic content. A chromatographic method was developed for the rapid identification of the main phenolics in the samples by HPLC-DAD and HPLC-MS. The fast fingerprint analysis allowed the detection of eighteen flavonoid C-glycosides and four flavonoid O-glycoside derivatives which were characterized by UV spectra and ESI-MS-MS analysis. Several of the C-glycosides detected are structurally related to the orientin derivative 4'-methoxy-luteolin-8-C-(6"acetyl)-b-D-glucopyranoside (31), fully elucidated by spectroscopic methods. The antioxidant derivative 31 along with schaftoside, vicenin II, orientin and vitexin were isolated from the fruit extract by high-speed countercurrent chromatography (HSCCC). A suitable method for the preparative isolation of flavonol C-glycosides from "tumbo" extracts by HSCCC is reported. The pulp of the fruits showed good antioxidant capacity (12.89 ± 0.02 mg/mL in the DPPH assay). The peel presented the highest content of flavonoids (56.03 ± 4.34 mg quercetin/100 g dry weight) which is related to the highest antioxidant power (10.41 ± 0.01 mg/mL in the DPPH assay).

  2. Resin glycosides from Ipomoea tyrianthina and their sedative and vasorelaxant effects.

    PubMed

    León-Rivera, Ismael; Castro, José Manuel; Mirón-López, Gumersindo; del Río-Portilla, Federico; Enríquez, Raúl G; Reynolds, William F; Estrada-Soto, Samuel; Rendón-Vallejo, Priscilla; del Carmen Gutiérrez, María; Herrera-Ruiz, Maribel; Mendoza, Angeles; Vargas, Gabriela

    2014-10-01

    The methanol-soluble extract from the root of Ipomoea tyrianthina was studied in order to isolate compounds with activity on the central nervous system and vasorelaxant effects. Chromatographic methods were used to isolate and purify seven new glycolipids (2-8). The structures of compounds 1-8 were elucidated by a combination of NMR spectroscopy and mass spectrometry. Tyrianthinoic acid (1) is a glycosidic acid composed of a linear pentasaccharide core bonded to a 11-hydroxyhexadecanoic acid. The structure of tyrianthinic acids III (2), IV (3), and V (4) consists of a partially acylated tyrianthinoic acid. Tyrianthinic acid VI (8) is a tetrasaccharide core bonded to a jalapinolic acid, acylated by a 2-methyl-3-hydroxybutanoic acid. Tyrianthins C (5), D (6), and E (7) are ester-type heterodimers of scammonic acid A with different acylating residues in the two monomeric units. The macrolactonization site was located at C-3 of the rhamnose unit. The position of the ester linkage for monomeric unit B on the macrocyclic unit A was established at C-4 of the terminal quinovose. Compounds 5-7 increased the sleeping time induced by pentobarbital and the release of gamma-aminobutyric acid in brain cortex. In addition, compounds 5-7 showed significant in vitro relaxant effects on aortic rat rings, in endothelium- and concentration-dependent manners.

  3. Resin glycosides from Ipomoea tyrianthina and their sedative and vasorelaxant effects.

    PubMed

    León-Rivera, Ismael; Castro, José Manuel; Mirón-López, Gumersindo; del Río-Portilla, Federico; Enríquez, Raúl G; Reynolds, William F; Estrada-Soto, Samuel; Rendón-Vallejo, Priscilla; del Carmen Gutiérrez, María; Herrera-Ruiz, Maribel; Mendoza, Angeles; Vargas, Gabriela

    2014-10-01

    The methanol-soluble extract from the root of Ipomoea tyrianthina was studied in order to isolate compounds with activity on the central nervous system and vasorelaxant effects. Chromatographic methods were used to isolate and purify seven new glycolipids (2-8). The structures of compounds 1-8 were elucidated by a combination of NMR spectroscopy and mass spectrometry. Tyrianthinoic acid (1) is a glycosidic acid composed of a linear pentasaccharide core bonded to a 11-hydroxyhexadecanoic acid. The structure of tyrianthinic acids III (2), IV (3), and V (4) consists of a partially acylated tyrianthinoic acid. Tyrianthinic acid VI (8) is a tetrasaccharide core bonded to a jalapinolic acid, acylated by a 2-methyl-3-hydroxybutanoic acid. Tyrianthins C (5), D (6), and E (7) are ester-type heterodimers of scammonic acid A with different acylating residues in the two monomeric units. The macrolactonization site was located at C-3 of the rhamnose unit. The position of the ester linkage for monomeric unit B on the macrocyclic unit A was established at C-4 of the terminal quinovose. Compounds 5-7 increased the sleeping time induced by pentobarbital and the release of gamma-aminobutyric acid in brain cortex. In addition, compounds 5-7 showed significant in vitro relaxant effects on aortic rat rings, in endothelium- and concentration-dependent manners. PMID:24838512

  4. Profiling of Flavonol Derivatives for the Development of Antitrypanosomatidic Drugs.

    PubMed

    Borsari, Chiara; Luciani, Rosaria; Pozzi, Cecilia; Poehner, Ina; Henrich, Stefan; Trande, Matteo; Cordeiro-da-Silva, Anabela; Santarem, Nuno; Baptista, Catarina; Tait, Annalisa; Di Pisa, Flavio; Dello Iacono, Lucia; Landi, Giacomo; Gul, Sheraz; Wolf, Markus; Kuzikov, Maria; Ellinger, Bernhard; Reinshagen, Jeanette; Witt, Gesa; Gribbon, Philip; Kohler, Manfred; Keminer, Oliver; Behrens, Birte; Costantino, Luca; Tejera Nevado, Paloma; Bifeld, Eugenia; Eick, Julia; Clos, Joachim; Torrado, Juan; Jiménez-Antón, María D; Corral, María J; Alunda, José Ma; Pellati, Federica; Wade, Rebecca C; Ferrari, Stefania; Mangani, Stefano; Costi, Maria Paola

    2016-08-25

    Flavonoids represent a potential source of new antitrypanosomatidic leads. Starting from a library of natural products, we combined target-based screening on pteridine reductase 1 with phenotypic screening on Trypanosoma brucei for hit identification. Flavonols were identified as hits, and a library of 16 derivatives was synthesized. Twelve compounds showed EC50 values against T. brucei below 10 μM. Four X-ray crystal structures and docking studies explained the observed structure-activity relationships. Compound 2 (3,6-dihydroxy-2-(3-hydroxyphenyl)-4H-chromen-4-one) was selected for pharmacokinetic studies. Encapsulation of compound 2 in PLGA nanoparticles or cyclodextrins resulted in lower in vitro toxicity when compared to the free compound. Combination studies with methotrexate revealed that compound 13 (3-hydroxy-6-methoxy-2-(4-methoxyphenyl)-4H-chromen-4-one) has the highest synergistic effect at concentration of 1.3 μM, 11.7-fold dose reduction index and no toxicity toward host cells. Our results provide the basis for further chemical modifications aimed at identifying novel antitrypanosomatidic agents showing higher potency toward PTR1 and increased metabolic stability. PMID:27411733

  5. Lipid Acyl Chain Remodeling in Yeast

    PubMed Central

    Renne, Mike F.; Bao, Xue; De Smet, Cedric H.; de Kroon, Anton I. P. M.

    2015-01-01

    Membrane lipid homeostasis is maintained by de novo synthesis, intracellular transport, remodeling, and degradation of lipid molecules. Glycerophospholipids, the most abundant structural component of eukaryotic membranes, are subject to acyl chain remodeling, which is defined as the post-synthetic process in which one or both acyl chains are exchanged. Here, we review studies addressing acyl chain remodeling of membrane glycerophospholipids in Saccharomyces cerevisiae, a model organism that has been successfully used to investigate lipid synthesis and its regulation. Experimental evidence for the occurrence of phospholipid acyl chain exchange in cardiolipin, phosphatidylcholine, phosphatidylinositol, and phosphatidylethanolamine is summarized, including methods and tools that have been used for detecting remodeling. Progress in the identification of the enzymes involved is reported, and putative functions of acyl chain remodeling in yeast are discussed. PMID:26819558

  6. Biophysical exploration of protein-flavonol recognition: effects of molecular properties and conformational flexibility.

    PubMed

    Ding, Fei; Peng, Wei; Peng, Yu-Kui

    2016-04-28

    The current work explores the biomolecular recognition of a series of flavonols by a protein and then uncovers the influences of the structural features of flavonols and the protein's own characteristics, e.g. the dynamics and flexibility, on the bioavailability of flavonols by using the pivotal biomacromolecule hemoglobin as a model. The experimental results revealed that flavonol may lead to a notable decrease in the steady-state fluorescence intensity of the β-37 Trp residue, and in the meantime the R-T transition of the protein transpired. Such noncovalent recognition forms the ground-state adduct, with an association intensity of 3.991 × 10(4) M(-1) in the reaction process, which has already been authenticated by the detailed analysis of time-resolved fluorescence and UV/vis absorption spectra. Furthermore, flavonol can form hydrogen bonds and π-conjugation effects with several amino acid residues on the polypeptide chain, for example, Trp-37, Arg-40, Asp-99 and Asn-102, and this event would induce self-regulation of the compact, regular conformation of the protein to a certain extent, which explicitly corroborates the results of circular dichroism. According to the study of molecular docking and structure-activity relationships, we could see that the recognition capacities of the protein-flavonols are inversely interrelated with the C log P values of the flavonol molecules. Moreover, the properties of the substituents in the structural B-ring unit of flavonols, i.e. polarity, position and number, will also prominently affect the degree of affinity and bioavailability of the protein-flavonol complexes. The analytical results of molecular dynamics (MD) simulation testified that the discussions of the structure-activity relationships are entirely logical, and the conformations of the amino acid residues forming noncovalent interactions tend to be stable in the MD simulation, as further elucidated from the dynamics data. Plainly, molecular recognition of

  7. A new furostanol glycoside from Tribulus terrestris.

    PubMed

    Xu, Yajuan; Liu, Yonghong; Xu, Tunhai; Xie, Shengxu; Si, Yunshan; Liu, Yue; Zhou, Haiou; Liu, Tonghua; Xu, Dongming

    2010-01-27

    Besides two known glycosides, a new furostanol glycoside was isolated from the Fruits of Tribulus terrestris L. The structure of the new furostanol glycoside was established as 26-O-beta-D-glucopyranosyl-(25S)-5alpha-furostane-20(22)-en-12-one-3beta, 26-diol-3-O-alpha-L-rhamnopyranosyl-(1-->2)-[beta-D-glucopyranosyl-(1-->4)]-beta-D-galactopyranoside (1) on the basis of 1D and 2D-NMR techniques, including COSY, HMBC, and HMQC correlations.

  8. Hepatoprotective glycosides from Leonurus japonicus Houtt.

    PubMed

    Li, Yixiu; Chen, Zhong; Feng, Ziming; Yang, Yanan; Jiang, Jianshuang; Zhang, Peicheng

    2012-02-01

    Two new phenylethanoid glycosides 1 and 2 named leonoside E and leonoside F, and one new sesquiterpene glycoside (3) identified as 7α (H)-eudesmane-4,11 (12)-diene-3-one-2β-hydroxy-13-β-d-glucopyranoside, together with seven known glycosides (4-10), were isolated from the aerial part of Leonurus japonicus Houtt. Their structures were elucidated on the basis of spectroscopic data and chemical evidence. When tested in in vitro assays, compounds 1, 2, 4, and 6 exhibited potent hepatoprotective activity against d-galactosamine-induced toxicity in HL-7702 cells at concentration of 1×10(-5) M.

  9. 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

  10. Chelation behavior of various flavonols and transfer of flavonol-chelated zinc(II) to alanylaspartic dipeptide: A PCM/DFT investigation

    NASA Astrophysics Data System (ADS)

    Yasarawan, Nuttawisit; Thipyapong, Khajadpai; Ruangpornvisuti, Vithaya

    2016-03-01

    Alanylaspartic dipeptide (AlaAsp) and zinc(II)-flavonol complex could represent a metal-binding site in proteins and a metal-ion releasing agent, respectively. Chelation of zinc(II) by either AlaAsp or flavonol ligands in aqueous solution has been examined using DFT methods with polarizable continuum model (PCM/DFT). Coordination geometry, complexation stoichiometry, coordination bond strength, preferable metal-binding site on ligands and effect of water coordination on the stability of complexes have been addressed. In several cases, the long-range corrected density functional CAM-B3LYP allows the most accurate prediction of both structural and spectroscopic data. The preferential transfer of flavonol-chelated zinc(II) to AlaAsp under solvation is attainable through the ligand-exchange reaction. The energy barrier of such reaction is significantly dependent on the degree of hydrogen bonding within the transition state. In summary, either hydroxylation or methoxylation at particular positions on the 3-hydroxyflavone backbone significantly affects the reactivity of flavonol chelates in the metal-ion transfer.

  11. Approach to the study of flavone di-C-glycosides by high performance liquid chromatography-tandem ion trap mass spectrometry and its application to characterization of flavonoid composition in Viola yedoensis.

    PubMed

    Cao, Jie; Yin, Chengle; Qin, Yan; Cheng, Zhihong; Chen, Daofeng

    2014-10-01

    The mass spectrometric (MS) analysis of flavone di-C-glycosides has been a difficult task due to pure standards being unavailable commercially and to that the reported relative intensities of some diagnostic ions varied with MS instruments. In this study, five flavone di-C-glycoside standards from Viola yedoensis have been systematically studied by high performance liquid chromatography-electrospray ionization-tandem ion trap mass spectrometry (HPLC-ESI-IT-MS(n)) in the negative ion mode to analyze their fragmentation patterns. A new MS(2) and MS(3) hierarchical fragmentation for the identification of the sugar nature (hexoses or pentoses) at C-6 and C-8 is presented based on previously established rules of fragmentation. Here, for the first time, we report that the MS(2) and MS(3) structure-diagnostic fragments about the glycosylation types and positions are highly dependent on the configuration of the sugars at C-6 and C-8. The base peak ((0,2) X1 (0,2) X(2)(-) ion) in MS(3) spectra of di-C-glycosides could be used as a diagnostic ion for flavone aglycones. These newly proposed fragmentation behaviors have been successfully applied to the characterization of flavone di-C-glycosides found in V. yedoensis. A total of 35 flavonoid glycosides, including 1 flavone mono-C-hexoside, 2 flavone 6,8-di-C-hexosides, 11 flavone 6,8-di-C-pentosides, 13 flavone 6,8-C-hexosyl-C-pentosides, 5 acetylated flavone C-glycosides and 3 flavonol O-glycosides, were identified or tentatively identified on the base of their UV profiles, MS and MS(n) (n = 5) data, or by comparing with reference substances. Among these, the acetylated flavone C-glycosides were reported from V. yedoensis for the first time.

  12. HPLC-DAD-ESI/MS(n) profiling of phenolic compounds from Lathyrus cicera L. seeds.

    PubMed

    Ferreres, F; Magalhães, S C Q; Gil-Izquierdo, A; Valentão, P; Cabrita, A R J; Fonseca, A J M; Andrade, P B

    2017-01-01

    Lathyrus cicera L. seeds are of interest for food and feed purposes. Despite the recognized antioxidant activity of the seeds, arising from the phenolic fraction, their phenolic compounds have not been studied in depth yet. Therefore, to determine the phenolics profile of these seeds, a target analysis was performed using high-performance liquid chromatography coupled to photodiode-array detection and electrospray ionization/ion trap mass spectrometry (HPLC-DAD-ESI/MS(n)). Thirty-seven glycosylated flavonoids were identified for the first time in the seeds of this species and, according to their MS fragmentation, clustered in flavonol-3-O-di-/tri-glycosides-7-O-rhamnosides and other flavonol-glycosides, and flavonol-3-O-(cinnamoyl)glycoside-7-O-rhamnosides, flavonol-3-O-(dihydrophaseoyl, cinnamoyl)glycoside-7-O-rhamnosides and flavonol-3-O-(malonyl)glycoside-7-O-rhamnosides. Glycosides of kaempferol were the main flavonoids found (10 non-acylated and 21 acylated), followed by those of quercetin (3) and those of isorhamnetin, apigenin and luteolin (1). The most abundant flavonols were identified as kaempferol-3-O-(2-hexosyl)hexoside-7-O-rhamnosides. The methodology used allowed to increase the knowledge on a relevant phytochemical class of seeds from L. cicera. PMID:27507525

  13. HPLC-DAD-ESI/MS(n) profiling of phenolic compounds from Lathyrus cicera L. seeds.

    PubMed

    Ferreres, F; Magalhães, S C Q; Gil-Izquierdo, A; Valentão, P; Cabrita, A R J; Fonseca, A J M; Andrade, P B

    2017-01-01

    Lathyrus cicera L. seeds are of interest for food and feed purposes. Despite the recognized antioxidant activity of the seeds, arising from the phenolic fraction, their phenolic compounds have not been studied in depth yet. Therefore, to determine the phenolics profile of these seeds, a target analysis was performed using high-performance liquid chromatography coupled to photodiode-array detection and electrospray ionization/ion trap mass spectrometry (HPLC-DAD-ESI/MS(n)). Thirty-seven glycosylated flavonoids were identified for the first time in the seeds of this species and, according to their MS fragmentation, clustered in flavonol-3-O-di-/tri-glycosides-7-O-rhamnosides and other flavonol-glycosides, and flavonol-3-O-(cinnamoyl)glycoside-7-O-rhamnosides, flavonol-3-O-(dihydrophaseoyl, cinnamoyl)glycoside-7-O-rhamnosides and flavonol-3-O-(malonyl)glycoside-7-O-rhamnosides. Glycosides of kaempferol were the main flavonoids found (10 non-acylated and 21 acylated), followed by those of quercetin (3) and those of isorhamnetin, apigenin and luteolin (1). The most abundant flavonols were identified as kaempferol-3-O-(2-hexosyl)hexoside-7-O-rhamnosides. The methodology used allowed to increase the knowledge on a relevant phytochemical class of seeds from L. cicera.

  14. Auxin and Ethylene Induce Flavonol Accumulation through Distinct Transcriptional Networks1[C][W][OA

    PubMed Central

    Lewis, Daniel R.; Ramirez, Melissa V.; Miller, Nathan D.; Vallabhaneni, Prashanthi; Ray, W. Keith; Helm, Richard F.; Winkel, Brenda S.J.; Muday, Gloria K.

    2011-01-01

    Auxin and ethylene are key regulators of plant growth and development, and thus the transcriptional networks that mediate responses to these hormones have been the subject of intense research. This study dissected the hormonal cross talk regulating the synthesis of flavonols and examined their impact on root growth and development. We analyzed the effects of auxin and an ethylene precursor on roots of wild-type and hormone-insensitive Arabidopsis (Arabidopsis thaliana) mutants at the transcript, protein, and metabolite levels at high spatial and temporal resolution. Indole-3-acetic acid (IAA) and 1-aminocyclopropane-1-carboxylic acid (ACC) differentially increased flavonol pathway transcripts and flavonol accumulation, altering the relative abundance of quercetin and kaempferol. The IAA, but not ACC, response is lost in the transport inhibitor response1 (tir1) auxin receptor mutant, while ACC responses, but not IAA responses, are lost in ethylene insensitive2 (ein2) and ethylene resistant1 (etr1) ethylene signaling mutants. A kinetic analysis identified increases in transcripts encoding the transcriptional regulators MYB12, Transparent Testa Glabra1, and Production of Anthocyanin Pigment after hormone treatments, which preceded increases in transcripts encoding flavonoid biosynthetic enzymes. In addition, myb12 mutants were insensitive to the effects of auxin and ethylene on flavonol metabolism. The equivalent phenotypes for transparent testa4 (tt4), which makes no flavonols, and tt7, which makes kaempferol but not quercetin, showed that quercetin derivatives are the inhibitors of basipetal root auxin transport, gravitropism, and elongation growth. Collectively, these experiments demonstrate that auxin and ethylene regulate flavonol biosynthesis through distinct signaling networks involving TIR1 and EIN2/ETR1, respectively, both of which converge on MYB12. This study also provides new evidence that quercetin is the flavonol that modulates basipetal auxin transport

  15. A general synthetic strategy and the anti-proliferation properties on prostate cancer cell lines for natural phenylethanoid glycosides.

    PubMed

    Mulani, Shaheen K; Guh, Jih-Hwa; Mong, Kwok-Kong Tony

    2014-05-14

    A general strategy for the synthesis of phenylethanoid glycosides (PhG) including echinacoside 1, acteoside 2, calceolarioside-A 3 and calceolarioside-B 4 is reported. The strategy features the application of low substrate concentration glycosylation and N-formyl morpholine modulated glycosylation methods for the construction of 1,2-trans β- and α-glycosidic bonds. The reported strategy does not invoke the use of the participatory acyl protecting function, which is incompatible with the ester function present in target PhG compounds. A preliminary study of the anti-proliferation properties of the PhG compounds 1–4 was performed; the acteoside 2 exhibited the best inhibition on the prostatic cancer cell proliferation.

  16. Acyl-acyl-carrier protein: lysomonogalactosyldiacylglycerol acyltransferase from the cyanobacterium Anabaena variabilis.

    PubMed

    Chen, H H; Wickrema, A; Jaworski, J G

    1988-12-16

    Membranes isolated from the cyanobacterium, Anabaena variabilis, and washed free of soluble endogenous constituents, were capable of catalyzing the direct transfer of the acyl group from acyl-acyl-carrier protein to an endogenous lysomonogalactosyldiacylglycerol to form monogalactosyldiacylglycerol. Other glycolipids including monoglucosyldiacylglycerol and digalactosyldiacylglycerol were not products of this reaction. The transfer was not dependent on any added cofactors. Palmitoyl-, stearoyl- and oleoyl-acyl-carrier protein were approximately equally active as substrates. Transfer was exclusively to the C-1 of the glycerol, as demonstrated by hydrolysis of all incorporated acyl groups by the lipase from Rhizopus arrhizus delamar. In addition to the single galactolipid, a second minor reaction product was free fatty acid, presumably due to hydrolysis of the acyl-acyl-carrier protein. Using a double-labelled [14C]acyl-[14C]acyl-carrier protein, the reaction was demonstrated to be a transfer reaction, rather than a simple exchange of acyl groups with endogenous monogalactosyldiacylglycerol. The transfer reaction mechanism was also confirmed by increasing activity with the addition of liposomes of lysomonogalactosyldiacylglycerol.

  17. Characterization of Flavonoid Glycosides from Fenugreek (Trigonella foenum-graecum) Crude Seeds by HPLC–DAD–ESI/MS Analysis

    PubMed Central

    Benayad, Zakia; Gómez-Cordovés, Carmen; Es-Safi, Nour Eddine

    2014-01-01

    Fenugreek (Trigonella foenum-graecum) is a medicinal plant which is widely used for its pharmacological properties. In this study the phenolic composition of fenugreek crude seeds originating from Morocco has been investigated. Extraction was performed from defatted seeds by a hydromethanolic solution using an Accelerated Solvent Extractor. HPLC technique coupled to negative ion electrospray ionization mass spectrometry and diode array detection was employed to identify the polyphenol in the obtained extract. The obtained results allowed the detection of 32 phenolic compounds among which various flavonoid glycosides and phenolic acids have been tentatively identified on the basis of their UV and MS spectra, and comparisons with standards when available, as well as with literature data. A systematic study of the obtained MS spectra and the observed fragmentation showed that most of the identified compounds were acylated and non-acylated flavonoids with apigenin, luteolin and kaempferol as aglycons. Hydroxycinnamic acids mostly dominated by caffeic acid derivatives were also detected. The quantitative analysis of the identified compounds showed that the phenolic composition of the studied crude fenugreek seeds was predominantly acylated and non-acylated flavone derivatives with apigenin as the main aglycon. PMID:25393509

  18. Antiviral Effect of Methylated Flavonol Isorhamnetin against Influenza

    PubMed Central

    Dayem, Ahmed Abdal; Choi, Hye Yeon; Kim, Young Bong; Cho, Ssang-Goo

    2015-01-01

    Influenza is an infectious respiratory disease with frequent seasonal epidemics that causes a high rate of mortality and morbidity in humans, poultry, and animals. Influenza is a serious economic concern due to the costly countermeasures it necessitates. In this study, we compared the antiviral activities of several flavonols and other flavonoids with similar, but distinct, hydroxyl or methyl substitution patterns at the 3, 3′, and 4′ positions of the 15-carbon flavonoid skeleton, and found that the strongest antiviral effect was induced by isorhamnetin. Similar to quercetin and kaempferol, isorhamnetin possesses a hydroxyl group on the C ring, but it has a 3′-methyl group on the B ring that is absent in quercetin and kaempferol. Co-treatment and pre-treatment with isorhamnetin produced a strong antiviral effect against the influenza virus A/PR/08/34(H1N1). However, isorhamnetin showed the most potent antiviral potency when administered after viral exposure (post-treatment method) in vitro. Isorhamnetin treatment reduced virus-induced ROS generation and blocked cytoplasmic lysosome acidification and the lipidation of microtubule associated protein1 light chain 3-B (LC3B). Oral administration of isorhamnetin in mice infected with the influenza A virus significantly decreased lung virus titer by 2 folds, increased the survival rate which ranged from 70–80%, and decreased body weight loss by 25%. In addition, isorhamnetin decreased the virus titer in ovo using embryonated chicken eggs. The structure-activity relationship (SAR) of isorhamnetin could explain its strong anti-influenza virus potency; the methyl group located on the B ring of isorhamnetin may contribute to its strong antiviral potency against influenza virus in comparison with other flavonoids. PMID:25806943

  19. Antiviral effect of methylated flavonol isorhamnetin against influenza.

    PubMed

    Abdal Dayem, Ahmed; Choi, Hye Yeon; Kim, Young Bong; Cho, Ssang-Goo

    2015-01-01

    Influenza is an infectious respiratory disease with frequent seasonal epidemics that causes a high rate of mortality and morbidity in humans, poultry, and animals. Influenza is a serious economic concern due to the costly countermeasures it necessitates. In this study, we compared the antiviral activities of several flavonols and other flavonoids with similar, but distinct, hydroxyl or methyl substitution patterns at the 3, 3', and 4' positions of the 15-carbon flavonoid skeleton, and found that the strongest antiviral effect was induced by isorhamnetin. Similar to quercetin and kaempferol, isorhamnetin possesses a hydroxyl group on the C ring, but it has a 3'-methyl group on the B ring that is absent in quercetin and kaempferol. Co-treatment and pre-treatment with isorhamnetin produced a strong antiviral effect against the influenza virus A/PR/08/34(H1N1). However, isorhamnetin showed the most potent antiviral potency when administered after viral exposure (post-treatment method) in vitro. Isorhamnetin treatment reduced virus-induced ROS generation and blocked cytoplasmic lysosome acidification and the lipidation of microtubule associated protein1 light chain 3-B (LC3B). Oral administration of isorhamnetin in mice infected with the influenza A virus significantly decreased lung virus titer by 2 folds, increased the survival rate which ranged from 70-80%, and decreased body weight loss by 25%. In addition, isorhamnetin decreased the virus titer in ovo using embryonated chicken eggs. The structure-activity relationship (SAR) of isorhamnetin could explain its strong anti-influenza virus potency; the methyl group located on the B ring of isorhamnetin may contribute to its strong antiviral potency against influenza virus in comparison with other flavonoids.

  20. Dietary flavonol intake is associated with age of puberty in a longitudinal cohort of girls

    PubMed Central

    Mervish, Nancy A.; Gardiner, Eliza W.; Galvez, Maida P.; Kushi, Larry H.; Windham, Gayle C.; Biro, Frank M.; Pinney, Susan M.; Rybak, Michael; Teitelbaum, Susan L.; Wolff, Mary S.

    2013-01-01

    Lignans and flavonols are dietary phytoestrogens found at high concentrations in the Western Diet. They have potential to influence the timing of puberty. We hypothesized that greater consumption of these two phytoestrogens would be related to later age at pubertal onset among girls. Pubertal assessment and 24-hour diet recall data were available for 1178 girls, ages 6-8 yr (mean 7.3 yr) in the Breast Cancer and Environment Research Project Puberty Study. Lignan and flavonol intakes were mainly derived from fruit and vegetable consumption. Average consumption was 6.5 mg/day for flavonols and 0.6 mg/day for lignans. Highest flavonol consumption (>5mg/day) was associated with later breast development (adjusted Hazards Ratio (HR): 0.74, 95% CI: [0.61-0.91]) compared to 2-5mg/day (adjusted HR: 0.84, 95% CI: [0.70-1.0]) and <2 mg/day (referent group; p-trend=0.006). Flavonol intake was not associated with pubic hair development. Lignan intake was not associated with either breast or pubic hair development. Dietary intake was only weakly correlated with urinary enterolactone, a biomarker for lignans (RS=0.13). Consistent with biologic properties of phytoestrogens that indicate hormonal activity, their consumption may be associated with reproductive endpoints, even in childhood. PMID:23827127

  1. Regulation of fatty acid elongation and initiation by acyl-acyl carrier protein in Escherichia coli.

    PubMed

    Heath, R J; Rock, C O

    1996-01-26

    Long chain acyl-acyl carrier protein (acyl-ACP) has been implicated as a physiological inhibitor of fatty acid biosynthesis since acyl-ACP degradation by thioesterase overexpression leads to constitutive, unregulated fatty acid production. The biochemical targets for acyl-ACP inhibition were unknown, and this work identified two biosynthetic enzymes that were sensitive to acyl-ACP feedback inhibition. Palmitoyl-ACP inhibited the incorporation of [14C]malonyl-CoA into long chain fatty acids in cell-free extracts of Escherichia coli. A short chain acyl-ACP species with the electrophoretic properties of beta-hydroxybutyryl-ACP accumulated concomitant with the overall decrease in the amount of [14C]malonyl-CoA incorporation, indicating that the first elongation cycle was targeted by acyl-ACP. All of the proteins required to catalyze the first round of fatty acid synthesis from acetyl-CoA plus malonyl-CoA in vitro were isolated, and the first fatty acid elongation cycle was reconstituted with these purified components. Analysis of the individual enzymes and the pattern of intermediate accumulation in the reconstituted system identified initiation of fatty acid synthesis by beta-ketoacyl-ACP synthase III (fabH) and enoyl-ACP reductase (fabI) in the elongation cycle as two steps attenuated by long chain acyl-ACP.

  2. Apple flavonols and n-3 polyunsaturated fatty acid-rich fish oil lowers blood C-reactive protein in rats with hypercholesterolemia and acute inflammation.

    PubMed

    Sekhon-Loodu, Satvir; Catalli, Adriana; Kulka, Marianna; Wang, Yanwen; Shahidi, Fereidoon; Rupasinghe, H P Vasantha

    2014-06-01

    Both quercetin glycosides and omega-3 polyunsaturated fatty acids (n-3 PUFA) are well established for their individual health benefits in ameliorating metabolic disease. However, their combined effects are not well documented. It was hypothesized that the beneficial properties of quercetin glycosides can be enhanced when provided in combination with n-3 PUFA. Therefore, the aim of the present study was to investigate the effects of apple flavonols (AF) and fish oil (FO), alone and in combination, on proinflammatory biomarkers and lipid profiles in rats fed a high-fat diet. Sixty male Wistar rats were randomly divided into 5 groups (n = 12) and fed a high-fat diet for 4 weeks. One of the 5 groups of rats was used as the high-fat control. The other 4 groups of rats were injected with lipopolysaccharide (LPS) (5 mg/kg body weight) intraperitoneally, 5 hours before euthanization. One of these 4 groups was used as the hypercholerolemic and inflammatory control (high-fat with lipopolysaccharide [HFL]), and the other 3 received AF (HFL + 25 mg/kg per day AF), FO (HFL + 1 g/kg per day FO), or the combination (HFL + AF + FO). Compared to the HFL group, the AF, FO, and AF + FO groups showed lower serum concentrations of interleukin-6 and C-reactive protein (CRP) levels. The AF, FO, and AF + FO also had lowered serum triacylglycerol and non-high-density lipoprotein cholesterol (HDL-C) concentrations, but higher HDL-C levels relative to the HFL group. An additive effect was observed on serum CRP in the AF + FO group as compared with the AF or FO groups. The results demonstrated that AF and FO inhibited the production of proinflammatory mediators and showed an improved efficacy to lower serum CRP when administered in combination, and they significantly improved blood lipid profiles in rats with diet-induced hyperlipidemia and LPS-induced acute inflammation.

  3. Apple flavonols and n-3 polyunsaturated fatty acid-rich fish oil lowers blood C-reactive protein in rats with hypercholesterolemia and acute inflammation.

    PubMed

    Sekhon-Loodu, Satvir; Catalli, Adriana; Kulka, Marianna; Wang, Yanwen; Shahidi, Fereidoon; Rupasinghe, H P Vasantha

    2014-06-01

    Both quercetin glycosides and omega-3 polyunsaturated fatty acids (n-3 PUFA) are well established for their individual health benefits in ameliorating metabolic disease. However, their combined effects are not well documented. It was hypothesized that the beneficial properties of quercetin glycosides can be enhanced when provided in combination with n-3 PUFA. Therefore, the aim of the present study was to investigate the effects of apple flavonols (AF) and fish oil (FO), alone and in combination, on proinflammatory biomarkers and lipid profiles in rats fed a high-fat diet. Sixty male Wistar rats were randomly divided into 5 groups (n = 12) and fed a high-fat diet for 4 weeks. One of the 5 groups of rats was used as the high-fat control. The other 4 groups of rats were injected with lipopolysaccharide (LPS) (5 mg/kg body weight) intraperitoneally, 5 hours before euthanization. One of these 4 groups was used as the hypercholerolemic and inflammatory control (high-fat with lipopolysaccharide [HFL]), and the other 3 received AF (HFL + 25 mg/kg per day AF), FO (HFL + 1 g/kg per day FO), or the combination (HFL + AF + FO). Compared to the HFL group, the AF, FO, and AF + FO groups showed lower serum concentrations of interleukin-6 and C-reactive protein (CRP) levels. The AF, FO, and AF + FO also had lowered serum triacylglycerol and non-high-density lipoprotein cholesterol (HDL-C) concentrations, but higher HDL-C levels relative to the HFL group. An additive effect was observed on serum CRP in the AF + FO group as compared with the AF or FO groups. The results demonstrated that AF and FO inhibited the production of proinflammatory mediators and showed an improved efficacy to lower serum CRP when administered in combination, and they significantly improved blood lipid profiles in rats with diet-induced hyperlipidemia and LPS-induced acute inflammation. PMID:25026921

  4. Antifibrotic Activity of Acylated and Unacylated Ghrelin

    PubMed Central

    Angelino, Elia; Reano, Simone; Ferrara, Michele; Agosti, Emanuela; Graziani, Andrea; Filigheddu, Nicoletta

    2015-01-01

    Fibrosis can affect almost all tissues and organs, it often represents the terminal stage of chronic diseases, and it is regarded as a major health issue for which efficient therapies are needed. Tissue injury, by inducing necrosis/apoptosis, triggers inflammatory response that, in turn, promotes fibroblast activation and pathological deposition of extracellular matrix. Acylated and unacylated ghrelin are the main products of the ghrelin gene. The acylated form, through its receptor GHSR-1a, stimulates appetite and growth hormone (GH) release. Although unacylated ghrelin does not bind or activate GHSR-1a, it shares with the acylated form several biological activities. Ghrelin peptides exhibit anti-inflammatory, antioxidative, and antiapoptotic activities, suggesting that they might represent an efficient approach to prevent or reduce fibrosis. The aim of this review is to summarize the available evidence regarding the effects of acylated and unacylated ghrelin on different pathologies and experimental models in which fibrosis is a predominant characteristic. PMID:25960743

  5. Fatty acyl-CoA reductase

    SciTech Connect

    Reiser, Steven E.; Somerville, Chris R.

    1998-12-01

    The present invention relates to bacterial enzymes, in particular to an acyl-CoA reductase and a gene encoding an acyl-CoA reductase, the amino acid and nucleic acid sequences corresponding to the reductase polypeptide and gene, respectively, and to methods of obtaining such enzymes, amino acid sequences and nucleic acid sequences. The invention also relates to the use of such sequences to provide transgenic host cells capable of producing fatty alcohols and fatty aldehydes.

  6. Characterization of a citrus R2R3-MYB transcription factor that regulates the flavonol and hydroxycinnamic acid biosynthesis

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Flavonols and hydroxycinnamic acids are important phenylpropanoid metabolites in plants. In this study, we isolated and characterized a citrus R2R3-MYB transcription factor CsMYBF1, encoding a protein belonging to the flavonol-specific MYB subgroup. Ectopic expression of CsMYBF1 in tomato led to an ...

  7. Diterpene glycosides from Stevia phlebophylla A. Gray.

    PubMed

    Ceunen, Stijn; Wim, De Borggraeve; Compernolle, Frans; Mai, Anh Hung; Geuns, Jan M C

    2013-09-20

    The rare Mexican species Stevia phlebophylla A. Gray was long considered to be the only known Stevia species, beside the well-known S. rebaudiana, containing the highly sweet diterpenoid steviol glycosides. We report a re-evaluation of this claim after phytochemically screening leaves obtained from two herbarium specimens of S. phlebophylla for the presence of steviol glycosides. Despite extensive MS analyses, no steviol glycosides could be unambiguously verified. Instead, the main chromatographic peak eluting at retention times similar to those of steviol glycosides was identified as a new compound, namely 16β-hydroxy-17-acetoxy-ent-kauran-19-oic acid-(6-O-β-D-xylopyranosyl-β-D-glucopyranosyl) ester (1) on the basis of extensive NMR and MS data as well as the characterization of its acid hydrolysate. Seven more compounds were detected by ESIMS which are possibly structurally related to 1. It can therefore be concluded that S. phlebophylla is unlikely to contain significant amounts of steviol glycosides, if any.

  8. Ultraviolet-B radiation and water deficit interact to alter flavonol and anthocyanin profiles in grapevine berries through transcriptomic regulation.

    PubMed

    Martínez-Lüscher, Johann; Sánchez-Díaz, Manuel; Delrot, Serge; Aguirreolea, Jone; Pascual, Inmaculada; Gomès, Eric

    2014-11-01

    UV-B radiation and water deficit may trigger flavonol and anthocyanin biosynthesis in plant tissues. In addition, previous research has showed strong qualitative effects on grape berry skin flavonol and anthocyanin profiles in response to UV-B and water deficit. The aim of this study is to identify the mechanisms leading to quantitative and qualitative changes in flavonol and anthocyanin profiles, in response to separate and combined UV-B and water deficit. Grapevines (Vitis vinifera L. cv. Tempranillo) were exposed to three levels of UV-B radiation (0, 5.98 and 9.66 kJ m(-2) day(-1)) and subjected to two water regimes. A strong effect of UV-B on flavonol and anthocyanin biosynthesis was found, resulting in an increased anthocyanin concentration and a change in their profile. Concomitantly, two key biosynthetic genes (FLS1 and UFGT) were up-regulated by UV-B, leading to increased flavonol and anthocyanin skin concentration. Changes in flavonol and anthocyanin composition were explained to a large extend by transcript levels of F3'H, F3'5'H and OMT2. A significant interaction between UV-B and water deficit was found in the relative abundance of 3'4' and 3'4'5' substituted flavonols, but not in their anthocyanin homologues. The ratio between 3'4'5' and 3'4' substituted flavonols was linearly related to the ratios of F3'5'H and FLS1 transcription, two steps up-regulated independently by water deficit and UV-B radiation, respectively. Our results indicate that changes in flavonol profiles in response to environmental conditions are not only a consequence of changes in the expression of flavonoid hydroxylases; but also the result of the competition of FLS, F3'5'H and F3'H enzymes for the same flavonol substrates. PMID:25231967

  9. Flavonol acylglycosides from flower of Albizia julibrissin and their inhibitory effects on lipid accumulation in 3T3-L1 cells.

    PubMed

    Yahagi, Tadahiro; Daikonya, Akihiro; Kitanaka, Susumu

    2012-01-01

    Obesity is a serious health problem worldwide. We investigated the anti-obesity effect of the flower of Albizia julibrissin DURAZZ. (Leguminosae). A 90% EtOH extract of the flower inhibited adipogenesis in 3T3-L1 preadipocytes, as well as the activity of glycerol-3-phosphate dehydrogenase (GPDH) activity. New flavonol acylglycosides (1-4) and eighteen known compounds (5-22) were isolated by bioassay-directed fractionation. These new glycosides were elucidated to be 3″-(E)-p-coumaroylquercitrin (1), 3″-(E)-feruloylquercitrin (2), 3″-(E)-cinnamoylquercitrin (3), and 2″-(E)-cinnamoylquercitrin (4) on the basis of spectroscopic and chemical analysis. These compounds inhibited adipogenesis in 3T3-L1 preadipocytes. In particular, 2 exhibited potent inhibitory effects on triglyceride accumulation. Furthermore, GPDH activity was inhibited by 2. Additionally, 2 inhibited glucose uptake in 3T3-L1 adipocytes. These results indicate that the 90% EtOH extract and compounds isolated from the flower of A. julibrissin inhibit adipogenesis in 3T3-L1 preadipocytes and may have anti-obesity effect through the inhibition of preadipocyte differentiation. PMID:22223384

  10. Monogalactosyldiacylglycerol biosynthesis by direct acyl transfer in Anabaene variabilis

    SciTech Connect

    Chen, H.H.; Wickrema, A.; Jaworski, J.

    1987-04-01

    The authors previously reported the direct acylation of monogalactosyldiacylglycerol (MGDG) by an enzyme in the membranes of the cyanobacterium Anabaena variabilis. The enzyme requires acyl-acyl carrier protein (acyl-ACP) as substrate, but had no other additional cofactor requirements. Palmitoyl-, stearoyl- and oleoyl-ACP were all effective substrates. The A. variabilis membranes also had a hydrolase activity which metabolized the acyl-ACP to yield free fatty acid and ACP. Possible mechanisms for the acylation reaction include either acyl exchange with existing MGDG or direct acyl transfer to a lyso-MGDG, with concomitant release of free ACP. The mechanism of this reaction has been resolved using a double labelled (/sup 14/C)acyl-(/sup 14/)ACP substrate prepared with E. coli acyl-ACP synthetase. Following incubation with the enzyme, the unreacted (/sup 14/)acyl-(/sup 14/)ACP was isolated and the (/sup 14/)acyl/(/sup 14/)ACP ratio determined. Comparison of this ratio to that of the original substrate indicated no change and eliminated acyl exchange as a possible mechanism. Therefore, the direct acylation of lyso-MGDG is the proposed mechanism for this enzyme.

  11. Phenylethanoid and aliphatic alcohol glycosides from Acanthus ilicifolius.

    PubMed

    Wu, Jun; Zhang, Si; Xiao, Qiang; Li, Qingxin; Huang, Jianshe; Long, Lijuan; Huang, Liangmin

    2003-06-01

    A phenylethanoid glycoside (ilicifolioside A) and an aliphatic alcohol glycoside (ilicifolioside B), have been isolated from the aerial parts of Acanthus ilicifolius, together with eight known compounds. Their structures were determined from spectroscopic analyses.

  12. Aberrant protein acylation is a common observation in inborn errors of acyl-CoA metabolism.

    PubMed

    Pougovkina, Olga; Te Brinke, Heleen; Wanders, Ronald J A; Houten, Sander M; de Boer, Vincent C J

    2014-09-01

    Inherited disorders of acyl-CoA metabolism, such as defects in amino acid metabolism and fatty acid oxidation can present with severe clinical symptoms either neonatally or later in life, but the pathophysiological mechanisms are often incompletely understood. We now report the discovery of a novel biochemical mechanism that could contribute to the pathophysiology of these disorders. We identified increased protein lysine butyrylation in short-chain acyl-CoA dehydrogenase (SCAD) deficient mice as a result of the accumulation of butyryl-CoA. Similarly, in SCAD deficient fibroblasts, lysine butyrylation was increased. Furthermore, malonyl-CoA decarboxylase (MCD) deficient patient cells had increased levels of malonylated lysines and propionyl-CoA carboxylase (PCC) deficient patient cells had increased propionylation of lysines. Since lysine acylation can greatly impact protein function, aberrant lysine acylation in inherited disorders associated with acyl-CoA accumulation may well play a role in their disease pathophysiology. PMID:24531926

  13. Microbial Tailoring of Acyl Peptidic Siderophores

    PubMed Central

    2015-01-01

    Marine bacteria produce an abundance of suites of acylated siderophores characterized by a unique, species-dependent headgroup that binds iron(III) and one of a series of fatty acid appendages. Marinobacter sp. DS40M6 produces a suite of seven acylated marinobactins, with fatty acids ranging from saturated and unsaturated C12–C18 fatty acids. In the present study, we report that in the late log phase of growth, the fatty acids are hydrolyzed by an amide hydrolase producing the peptidic marinobactin headgroup. Halomonas aquamarina str. DS40M3, another marine bacterium isolated originally from the same sample of open ocean water as Marinobacter sp. DS40M6, produces the acyl aquachelins, also as a suite composed of a peptidic headgroup distinct from that of the marinobactins. In contrast to the acyl marinobactins, hydrolysis of the suite of acyl aquachelins is not detected, even when H. aquamarina str. DS40M3 is grown into the stationary phase. The Marinobacter cell-free extract containing the acyl amide hydrolase is active toward exogenous acyl-peptidic siderophores (e.g., aquachelin C, loihichelin C, as well as octanoyl homoserine lactone used in quorum sensing). Further, when H. aquamarina str. DS40M3 is cultured together with Marinobacter sp. DS40M6, the fatty acids of both suites of siderophores are hydrolyzed, and the aquachelin headgroup is also produced. The present study demonstrates that coculturing bacteria leads to metabolically tailored metabolites compared to growth in a single pure culture, which is interesting given the importance of siderophore-mediated iron acquisition for bacterial growth and that Marinobacter sp. DS40M6 and H. aquamarina str. DS40M3 were isolated from the same sample of seawater. PMID:24735218

  14. Bioactive phenylpropanoid glycosides from Tabebuia avellanedae.

    PubMed

    Suo, Maorong; Ohta, Tomihisa; Takano, Fumihide; Jin, Shouwen

    2013-06-24

    Three novel phenylpropanoid glycosides 2, 5, 6 were isolated from water extract of Tabebuia avellanedae, together with three known phenylpropanoid glycosides 1, 3, 4. All compounds were identified on the basis of spectroscopic analysis and chemical methods and, for known compounds, by comparison with published data. All isolated compounds showed strong antioxidant activity in the DPPH assay, and compound 5 give the highest antioxidant activity among all compounds, with an IC₅₀ of 0.12 µM. All compounds exhibited moderate inhibitory effect on cytochrome CYP3A4 enzyme.

  15. Five new phenolic glycosides from Hedyotis scandens.

    PubMed

    Wang, Guo-Cai; Li, Tao; Deng, Fang-Ye; Li, Yao-Lan; Ye, Wen-Cai

    2013-03-01

    Five new phenolic glycosides, hedyotosides A-E (1-5), including a new cyanogenic glycoside (1), along with 10 known compounds (6-15) were isolated from the whole plants of Hedyotis scandens. The structures of compounds 1-5 were established by extensive spectroscopic analyses and acid hydrolysis. All the isolated compounds were evaluated for their in vitro antiviral activity against respiratory syncytial virus (RSV) with cytopathic effect (CPE) reduction assay. Compounds 6 and 15 showed anti-RSV effects with IC(50) values of 20 and 25 μg/mL, respectively. PMID:23333151

  16. Fatty acid, flavonol, and mineral composition variability among seven macrotyloma uniflorum (Lam.) verdc. accessions

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Horse gram [Macrotyloma uniflorum (Lam.) Verdc.] seeds containing high concentrations of fatty acids, flavonols and minerals will provide government, public and private organizations with a nutritious and healthy food for use by malnourished and food deprived people worldwide. Seeds from seven horse...

  17. Naphthalene glycosides in Cassia senna and Cassia angustifolia.

    PubMed

    Lemli, J; Toppet, S; Cuveele, J; Janssen, G

    1981-09-01

    From leaves and pods of Cassia senna L. and C. angustifolia Vahl. were isolated the naphthalene glycosides 6-hydroxymusizin glycoside and the new tinnevellin glycoside. The structures were established mainly by spectroscopic methods ( (1)H NMR, (13)C NMR, MS). PMID:17402001

  18. Identification and characterization of component organic and glycosidic acids of crude resin glycoside fraction from Calystegia soldanella.

    PubMed

    Takigawa, Ayako; Setoguchi, Hiroaki; Okawa, Masafumi; Kinjo, Junei; Miyashita, Hiroyuki; Yokomizo, Kazumi; Yoshimitsu, Hitoshi; Nohara, Toshihiro; Ono, Masateru

    2011-01-01

    Alkaline hydrolysis of the crude resin glycoside fraction of the leaves, stems, and roots of Calystegia soldanella ROEM. et SCHULT. (Convolvulaceae) gave four new glycosidic acids, named calysolic acids A, B, C, and D, along with one known glycosidic acid, soldanellic acid B, and three organic acids, 2S-methylbutyric, tiglic, and 2S,3S-nilic acids. The structures of the new glycosidic acids were characterized on the basis of spectroscopic data and chemical evidence.

  19. Anticancer Activity of Sea Cucumber Triterpene Glycosides

    PubMed Central

    Aminin, Dmitry L.; Menchinskaya, Ekaterina S.; Pisliagin, Evgeny A.; Silchenko, Alexandra S.; Avilov, Sergey A.; Kalinin, Vladimir I.

    2015-01-01

    Triterpene glycosides are characteristic secondary metabolites of sea cucumbers (Holothurioidea, Echinodermata). They have hemolytic, cytotoxic, antifungal, and other biological activities caused by membranotropic action. These natural products suppress the proliferation of various human tumor cell lines in vitro and, more importantly, intraperitoneal administration in rodents of solutions of some sea cucumber triterpene glycosides significantly reduces both tumor burden and metastasis. The anticancer molecular mechanisms include the induction of tumor cell apoptosis through the activation of intracellular caspase cell death pathways, arrest of the cell cycle at S or G2/M phases, influence on nuclear factors, NF-κB, and up-down regulation of certain cellular receptors and enzymes participating in cancerogenesis, such as EGFR (epidermal growth factor receptor), Akt (protein kinase B), ERK (extracellular signal-regulated kinases), FAK (focal adhesion kinase), MMP-9 (matrix metalloproteinase-9) and others. Administration of some glycosides leads to a reduction of cancer cell adhesion, suppression of cell migration and tube formation in those cells, suppression of angiogenesis, inhibition of cell proliferation, colony formation and tumor invasion. As a result, marked growth inhibition of tumors occurs in vitro and in vivo. Some holothurian triterpene glycosides have the potential to be used as P-gp mediated MDR reversal agents in combined therapy with standard cytostatics. PMID:25756523

  20. New triterpene glycosides from Ziziphi Spinosae Semen.

    PubMed

    Wang, Yu; Ding, Bo; Luo, Dan; Chen, Liu-Yuan; Hou, Yun-Long; Dai, Yi; Yao, Xin-Sheng

    2013-10-01

    Four new dammarane-type triterpene glycosides, named jujubosides I-IV (1-4), were isolated from Ziziphi Spinosae Semen, along with seven known saponins (5-11). The structures of new compounds were established on the basis of extensive spectroscopic analysis. All compounds were evaluated for the effects on neonatal rat cardiomyocyte injury induced by hydrogen peroxide in vitro. PMID:23912064

  1. A new isoflavone glycoside from Pueraria alopecuroides.

    PubMed

    Yang, Junlin; Fan, Qingfei; Zhang, Huanli; Song, Qishi

    2016-01-01

    A new isoflavone glycoside, (-)-tuberosin-3-O-β-D-glucopyranoside (1), along with 10 known compounds 1a-10, was isolated from Pueraria alopecuroides. Their structures were determined on the basis of spectral data including 1D and 2D NMR and HREIMS. These compounds were isolated from this plant for the first time. PMID:26525177

  2. Two new glycosides from Leonurus japonicus.

    PubMed

    Chang, Jin-Ming; Shen, Chien-Chang; Huang, Yu-Ling; Shieh, Bor-Jinn; Chen, Chien-Chih

    2010-09-01

    Two new glycosides, 1,6-di-O-syringoyl-β-D-glucopyranose (1) and quercetin 3-O-[(3-O-syringoyl-α-L-rhamnopyranosyl)-(1→6)-β-D-glucopyranoside] (2), along with seven known compounds were isolated from the MeOH extract of Leonurus japonicus. The structures of these compounds were elucidated by spectral analysis.

  3. Twisting of glycosidic bonds by hydrolases

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Patterns of scissile bond twisting have been found in crystal structures of glycoside hydrolases (GHs) that are complexed with substrates and inhibitors. To estimate the increased potential energy in the substrates that results from this twisting, we have plotted torsion angles for the scissile bond...

  4. New xanthone glycosides from Securidaca inappendiculata.

    PubMed

    Yang, Xue-Dong; An, Ning; Xu, Li-Zhen; Yang, Shi-Lin

    2002-06-01

    Three new xanthone glycosides, securixanside A (1), securixanside B (2), and securixanside C (3) were isolated from the stems of Securidaca inappendiculata. These compounds were characterized by spectrometric and chemical methods, including FABMS and one- and two-dimensional NMR experiments. PMID:12067160

  5. A new sterol glycoside from Securidaca inappendiculata.

    PubMed

    Zhang, Li-Jie; Yang, Xue-Dong; Xu, Li-Zhen; Zou, Zhong-Mei; Yang, Shi-Lin

    2005-08-01

    From the roots of Securidaca inappendiculata, one new sterol glycoside securisteroside (1) has been isolated, along with two known sterols, spinasterol (2) and 3-O-beta-D-glucopyranosyl-spinasterol (3). The new sterol was characterized by chemical and spectrometric methods, including EIMS, FABMS and one- and two-dimensional NMR experiments. PMID:16087640

  6. Immunosuppressive auronol glycosides from Artocarpus tonkinensis.

    PubMed

    Thuy, T T; Kamperdick, C; Ninh, P T; Lien, T P; Thao, T T P; Sung, T V

    2004-04-01

    Activity-guided fractionation of the n-butanol extract from the leaves of Artocarpus tonkinensis led to the isolation of the auronol glycosides maesopsin 4-O-glucoside (1), as well as the new alphitonin-4-O-glucoside (2). These structures were identified on the basis of MS and NMR spectroscopic data. The lymphocyte stimulation test showed both compounds having immunosuppressive activity.

  7. A new phenylethanoid glycoside from Clerodendrum inerme.

    PubMed

    Nan, Haihan; Wu, Jun; Zhang, Si

    2005-10-01

    A new phenylethanoid glycoside, 2-(3-methoxy-4-hydroxylphenyl) ethyl-O-2",3"-diacetyl-alpha-L-rhamnopyranosyl-(1-->3)-4-O-(E)-feruloyl-beta-D-glucopyranoside, was isolated from the aerial parts of Clerodendrum inerme (L.) Gaertn, together with monomelittoside, melittoside, inerminoside A1, verbascoside, isoverbascoside, campneoside I. Their structures were determined by spectroscopic methods.

  8. Cytotoxic resin glycosides from Ipomoea aquatica and their effects on intracellular Ca2+ concentrations.

    PubMed

    Fan, Bo-Yi; Gu, Yu-Cheng; He, Ye; Li, Zhong-Rui; Luo, Jian-Guang; Kong, Ling-Yi

    2014-10-24

    Eleven new resin glycosides, aquaterins I-XI (1-11), were isolated from the whole plants of Ipomoea aquatica. The structures of 1-11 were elucidated by a combination of spectroscopic and chemical methods. They were found to be partially acylated tetra- or pentasaccharides derived from simonic acid B and operculinic acids A and C. The site of the aglycone macrolactonization was placed at C-2 or C-3 of the second saccharide moiety, while the two acylating residues could be located at C-2 (or C-3) of the second rhamnose unit and at C-4 (or C-3) on the third rhamnose moiety. All compounds were evaluated for cytotoxicity against a small panel of human cancer cell lines. Compound 4 exhibited the most potent activity against HepG2 cells with an IC50 value of 2.4 μM. Cell cycle analysis revealed 4 to inhibit the proliferation of HepG2 cells via G0/G1 arrest and apoptosis induction. In addition, compounds 1-4, 7, 9, and 10 were found to elevate Ca(2+) in HepG2 cells, which might be involved in the regulation of the cytotoxic activities observed. PMID:25314138

  9. Enzymatic Processing of Bioactive Glycosides from Natural Sources

    NASA Astrophysics Data System (ADS)

    Weignerová, Lenka; Křen, Vladimír

    A number of biologically active natural products are glycosides. Often, the glycosidic residue is crucial for their activity. In other cases, glycosylation only improves their pharmacokinetic parameters. Enzymatic modification of these glycosides - both extension of the glycoside moiety and its selective trimming - is advantageous due to their selectivity and mildness of the reaction conditions in the presence of reactive and sensitive complex aglycones. Enzymatic reactions enable the resulting products to be used as "natural products", e.g., in nutraceuticals. This chapter concentrates on naturally occurring glycosides used in medicine but also in the food and flavor industry (e.g., sweeteners). Both "classical" and modern methods will be discussed.

  10. Triterpene glycosides of sea cucumbers (Holothuroidea, Echinodermata) as taxonomic markers.

    PubMed

    Kalinin, Vladimir I; Avilov, Sergey A; Silchenko, Alexandra S; Stonik, Valentin A

    2015-01-01

    Triterpene glycosides are characteristic metabolites of sea cucumbers (Holothurioidea, Echinodermata). The majority of the glycosides belong to the holostane type {lanostane derivatives with an 18(20)-lactone}. Carbohydrate chains of these glycosides contain xylose, glucose, quinovose, 3-O-methylglucose, and, rarely, 3-O-methylxylose, 3-O-methylglucuronic acid, 3-O-methylquinovose, and 6-O-acetyl-glucose. The glycosides are specific for genera, groups of genera and even for species. The advantages and problems in the use of triterpene glycosides as taxonomic markers in the systematics of sea cucumbers are discussed.

  11. Acyl-coenzyme A:cholesterol acyltransferases

    PubMed Central

    Chang, Ta-Yuan; Li, Bo-Liang; Chang, Catherine C. Y.; Urano, Yasuomi

    2009-01-01

    The enzymes acyl-coenzyme A (CoA):cholesterol acyltransferases (ACATs) are membrane-bound proteins that utilize long-chain fatty acyl-CoA and cholesterol as substrates to form cholesteryl esters. In mammals, two isoenzymes, ACAT1 and ACAT2, encoded by two different genes, exist. ACATs play important roles in cellular cholesterol homeostasis in various tissues. This chapter summarizes the current knowledge on ACAT-related research in two areas: 1) ACAT genes and proteins and 2) ACAT enzymes as drug targets for atherosclerosis and for Alzheimer's disease. PMID:19141679

  12. Phytochemical constituents, nutritional values, phenolics, flavonols, flavonoids, antioxidant and cytotoxicity studies on Phaleria macrocarpa (Scheff.) Boerl fruits

    PubMed Central

    2014-01-01

    Background The edible fruits of Phaleria macrocarpa (Scheff.) Boerl are widely used in traditional medicine in Indonesia. It is used to treat a variety of medical conditions such as - cancer, diabetes mellitus, allergies, liver and heart diseases, kidney failure, blood diseases, high blood pressure, stroke, various skin diseases, itching, aches, and flu. Therefore, it is of great interest to determine the biochemical and cytotoxic properties of the fruit extracts. Methods The methanol, hexane, chloroform, ethyl acetate, and water extracts of P. macrocarpa fruits were examined for phytochemicals, physicochemicals, flavonols, flavonoids and phenol content. Its nutritional value (A.O.A.C method), antioxidant properties (DPPH assay) and cytotoxicity (MTT cell proliferation assay) were also determined. Results A preliminary phyotochemical screening of the different crude extracts from the fruits of P. macrocarpa showed the presence secondary metabolites such as of flavonoids, phenols, saponin glycosides and tannins. The ethyl acetate and methanol extracts displayed high antioxidant acitivity (IC50 value of 8.15±0.02 ug/mL) in the DPPH assay comparable to that of the standard gallic acid (IC50 value of 10.8±0.02 ug/mL). Evaluation of cytotoxic activity showed that the crude methanol extract possessed excellent anti-proliferative activity against SKOV-3 (IC50 7.75±2.56 μg/mL) after 72 hours of treatment whilst the hexane and ethyl acetate extracts displayed good cytotoxic effect against both SKOV-3 and MDA-MB231 cell lines. The chloroform extract however, showed selective inhibitory activity in the breast cancer cell line MDA-MB231 (IC50 7.80±1.57 μg/mL) after 48 hours of treatment. There was no cytotoxic effect observed in the Ca Ski cell line and the two normal cell lines (MRC-5 and WRL-68). Conclusion The methanol extract and the ethyl acetate fraction of P. macrocarpa fruits exhibited good nutritional values, good antioxidant and cytotoxic activities, and merits

  13. Acyl silicates and acyl aluminates as activated intermediates in peptide formation on clays

    NASA Technical Reports Server (NTRS)

    White, D. H.; Kennedy, R. M.; Macklin, J.

    1984-01-01

    Glycine reacts with heating on dried clays and other minerals to give peptides in much better yield than in the absence of mineral. This reaction was proposed to occur by way of an activated intermediate such as an acyl silicate or acyl aluminate analogous to acyl phosphates involved in several biochemical reactions including peptide bond synthesis. The proposed mechanism has been confirmed by trapping the intermediate, as well as by direct spectroscopic observation of a related intermediate. The reaction of amino acids on periodically dried mineral surfaces represents a widespead, geologically realistic setting for prebiotic peptide formation via in situ activation.

  14. Advance on the Flavonoid C-glycosides and Health Benefits.

    PubMed

    Xiao, Jianbo; Capanoglu, Esra; Jassbi, Amir Reza; Miron, Anca

    2016-07-29

    The dietary flavonoids, especially their glycosides, are the most vital phytochemicals in diets and are of great general interest due to their diverse bioactivity. Almost all natural flavonoids exist as their O-glycoside or C-glycoside forms in plants. The dietary flavonoid C-glycosides have received less attention than their corresponding O-glycosides. This review summarizes current knowledge regarding flavonoid C-glycosides and their influence on human health. Among the flavonoid C-glycosides, flavone C-glycosides, especially vitexin, isoorientin, orientin, isovitexin and their multiglycosides are more frequently mentioned than others. Flavonoid C-monoglycosides are poorly absorbed in human beings with very few metabolites in urine and blood and are deglycosylated and degraded by human intestinal bacteria in colon. However, flavonoid C-multiglycosides are absorbed unchanged in the intestine and distributed to other tissues. Flavonoid C-glycosides showed significant antioxidant activity, anticancer and antitumor activity, hepatoprotective activity, anti-inflammatory activity, anti-diabetes activity, antiviral activity, antibacterial and antifungal activity, and other biological effects. It looks like that the C-glycosylflavonoids in most cases showed higher antioxidant and anti-diabetes potential than their corresponding O-glycosylflavonoids and aglycones. However, there is a lack of in vivo data on the biological benefits of flavonoid C-glycosides. It is necessary to investigate more on how flavonoid C-glycosides prevent and handle the diseases.

  15. Identification of N-Acyl Phosphatidylserine Molecules in Eukaryotic Cells

    PubMed Central

    Guan, Ziqiang; Li, Shengrong; Smith, Dale C.; Shaw, Walter A.; Raetz, Christian R. H.

    2008-01-01

    While profiling the lipidome of the mouse brain by mass spectrometry, we discovered a novel family of N-acyl phosphatidylserine (N-acyl-PS) molecules. These N-acyl-PS species were enriched by DEAE-cellulose column chromatography, and they were then characterized by accurate mass measurements, tandem mass spectrometry, liquid chromatography/mass spectrometry, and comparison to an authentic standard. Mouse brain N-acyl-PS molecules are heterogeneous and constitute about 0.1 % of the total lipid. In addition to various ester-linked fatty acyl chains on their glycerol backbones, the complexity of the N-acyl-PS series is further increased by the presence of diverse amide-linked N-acyl chains, which include saturated, mono-unsaturated and poly-unsaturated species. N-acyl-PS molecular species were also detected in the lipids of pig brain, mouse RAW264.7 macrophage tumor cells and yeast, but not E. coli. N-acyl-PSs may be biosynthetic precursors of N-acyl serine molecules, such as the recently reported signaling lipid N-arachidonoyl serine from bovine brain. We suggest that a phospholipase D might cleave N-acyl-PS to generate N-acyl serine, in analogy to the biosynthesis of the endocannabinoid N-arachidonoyl ethanolamine (anadamide) from N-arachidonoyl phosphatidylethanolamine. PMID:18031065

  16. A novel glucosylation reaction on anthocyanins catalyzed by acyl-glucose-dependent glucosyltransferase in the petals of carnation and delphinium.

    PubMed

    Matsuba, Yuki; Sasaki, Nobuhiro; Tera, Masayuki; Okamura, Masachika; Abe, Yutaka; Okamoto, Emi; Nakamura, Haruka; Funabashi, Hisakage; Takatsu, Makoto; Saito, Mikako; Matsuoka, Hideaki; Nagasawa, Kazuo; Ozeki, Yoshihiro

    2010-10-01

    Glucosylation of anthocyanin in carnations (Dianthus caryophyllus) and delphiniums (Delphinium grandiflorum) involves novel sugar donors, aromatic acyl-glucoses, in a reaction catalyzed by the enzymes acyl-glucose-dependent anthocyanin 5(7)-O-glucosyltransferase (AA5GT and AA7GT). The AA5GT enzyme was purified from carnation petals, and cDNAs encoding carnation Dc AA5GT and the delphinium homolog Dg AA7GT were isolated. Recombinant Dc AA5GT and Dg AA7GT proteins showed AA5GT and AA7GT activities in vitro. Although expression of Dc AA5GT in developing carnation petals was highest at early stages, AA5GT activity and anthocyanin accumulation continued to increase during later stages. Neither Dc AA5GT expression nor AA5GT activity was observed in the petals of mutant carnations; these petals accumulated anthocyanin lacking the glucosyl moiety at the 5 position. Transient expression of Dc AA5GT in petal cells of mutant carnations is expected to result in the transfer of a glucose moiety to the 5 position of anthocyanin. The amino acid sequences of Dc AA5GT and Dg AA7GT showed high similarity to glycoside hydrolase family 1 proteins, which typically act as β-glycosidases. A phylogenetic analysis of the amino acid sequences suggested that other plant species are likely to have similar acyl-glucose-dependent glucosyltransferases.

  17. GOAT induced ghrelin acylation regulates hedonic feeding.

    PubMed

    Davis, J F; Perello, M; Choi, D L; Magrisso, I J; Kirchner, H; Pfluger, P T; Tschoep, M; Zigman, J M; Benoit, S C

    2012-11-01

    Ghrelin is an orexigenic hormone that regulates homeostatic and reward-related feeding behavior. Recent evidence indicates that acylation of ghrelin by the gut enzyme ghrelin O-acyl transferase (GOAT) is necessary to render ghrelin maximally active within its target tissues. Here we tested the hypothesis that GOAT activity modulates food motivation and food hedonics using behavioral pharmacology and mutant mice deficient for GOAT and the ghrelin receptor (GHSR). We evaluated operant responding following pharmacological administration of acyl-ghrelin and assessed the necessity of endogenous GOAT activity for operant responding in GOAT and GHSR-null mice. Hedonic-based feeding behavior also was examined in GOAT-KO and GHSR-null mice using a "Dessert Effect" protocol in which the intake of a palatable high fat diet "dessert" was assessed in calorically-sated mice. Pharmacological administration of acyl-ghrelin augmented operant responding; notably, this effect was dependent on intact GHSR signaling. GOAT-KO mice displayed attenuated operant responding and decreased hedonic feeding relative to controls. These behavioral results correlated with decreased expression of the orexin-1 receptor in reward-related brain regions in GOAT-KO mice. In summary, the ability of ghrelin to stimulate food motivation is dependent on intact GHSR signaling and modified by endogenous GOAT activity. Furthermore, GOAT activity is required for hedonic feeding behavior, an effect potentially mediated by forebrain orexin signaling. These data highlight the significance of the GOAT-ghrelin system for the mediation of food motivation and hedonic feeding.

  18. Regulation of flavonol content and composition in (Syrah×Pinot Noir) mature grapes: integration of transcriptional profiling and metabolic quantitative trait locus analyses

    PubMed Central

    Malacarne, Giulia; Costantini, Laura; Coller, Emanuela; Battilana, Juri; Velasco, Riccardo; Vrhovsek, Urska; Grando, Maria Stella; Moser, Claudio

    2015-01-01

    Flavonols are a ubiquitous class of flavonoids that accumulate preferentially in flowers and mature berries. Besides their photo-protective function, they play a fundamental role during winemaking, stabilizing the colour by co-pigmentation with anthocyanins and contributing to organoleptic characteristics. Although the general flavonol pathway has been genetically and biochemically elucidated, the genetic control of flavonol content and composition at harvest is still not clear. To this purpose, the grapes of 170 segregating F1 individuals from a ‘Syrah’×’Pinot Noir’ population were evaluated at the mature stage for the content of six flavonol aglycons in four seasons. Metabolic data in combination with genetic data enabled the identification of 16 mQTLs (metabolic quantitative trait loci). For the first time, major genetic control by the linkage group 2 (LG 2)/MYBA region on flavonol variation, in particular of tri-hydroxylated flavonols, is demonstrated. Moreover, seven regions specifically associated with the fine control of flavonol biosynthesis are identified. Gene expression profiling of two groups of individuals significantly divergent for their skin flavonol content identified a large set of differentially modulated transcripts. Among these, the transcripts coding for MYB and bZIP transcription factors, methyltranferases, and glucosyltranferases specific for flavonols, proteins, and factors belonging to the UV-B signalling pathway and co-localizing with the QTL regions are proposed as candidate genes for the fine regulation of flavonol content and composition in mature grapes. PMID:26071529

  19. Domestication in Murtilla (Ugni molinae) Reduced Defensive Flavonol Levels but Increased Resistance Against a Native Herbivorous Insect.

    PubMed

    Chacón-Fuentes, Manuel; Parra, Leonardo; Rodriguez-Saona, Cesar; Seguel, Ivette; Ceballos, Ricardo; Quiroz, Andres

    2015-06-01

    Plant domestication can have negative consequences for defensive traits against herbivores, potentially reducing the levels of chemical defenses in plants and consequently their resistance against herbivores. We characterized and quantified the defensive flavonols from multiple cultivated ecotypes with wild ancestors of murtilla, Ugni molinae Turcz, an endemic plant from Chile, at different times of the year, and examined their effects on a native insect herbivore, Chilesia rudis Butler (Lepidoptera: Arctiidae). We hypothesized that domestication results in a decrease in flavonol levels in U. molinae plants, and that this negatively affected C. rudis performance and preference. Ethanolic extracts were made from leaves, stems, and fruit of murtilla plants for flavonol analysis. Flavonols identified were kaempferol, quercetin, rutin, and quercetin 3-D-β-glucoside, the last two being the most abundant. More interestingly, we showed differences in flavonol composition between wild and cultivated U. molinae that persisted for most of the year. Relative amounts of all four flavonols were higher in wild U. molinae leaves; however, no differences were found in the stem and fruit between wild and cultivated plants. In choice and no-choice assays, C. rudis larvae gained more mass on, and consumed more leaf material of, wild as compared with cultivated U. molinae plants. Moreover, when applied to leaves, larvae ate more leaf material with increasing concentrations of each flavonol compound. Our study demonstrates that domestication in U. molinae reduced the amount of flavonols in leaves as well as the performance and preference of C. rudis, indicating that these compounds stimulate feeding of C. rudis.

  20. Domestication in Murtilla (Ugni molinae) Reduced Defensive Flavonol Levels but Increased Resistance Against a Native Herbivorous Insect.

    PubMed

    Chacón-Fuentes, Manuel; Parra, Leonardo; Rodriguez-Saona, Cesar; Seguel, Ivette; Ceballos, Ricardo; Quiroz, Andres

    2015-06-01

    Plant domestication can have negative consequences for defensive traits against herbivores, potentially reducing the levels of chemical defenses in plants and consequently their resistance against herbivores. We characterized and quantified the defensive flavonols from multiple cultivated ecotypes with wild ancestors of murtilla, Ugni molinae Turcz, an endemic plant from Chile, at different times of the year, and examined their effects on a native insect herbivore, Chilesia rudis Butler (Lepidoptera: Arctiidae). We hypothesized that domestication results in a decrease in flavonol levels in U. molinae plants, and that this negatively affected C. rudis performance and preference. Ethanolic extracts were made from leaves, stems, and fruit of murtilla plants for flavonol analysis. Flavonols identified were kaempferol, quercetin, rutin, and quercetin 3-D-β-glucoside, the last two being the most abundant. More interestingly, we showed differences in flavonol composition between wild and cultivated U. molinae that persisted for most of the year. Relative amounts of all four flavonols were higher in wild U. molinae leaves; however, no differences were found in the stem and fruit between wild and cultivated plants. In choice and no-choice assays, C. rudis larvae gained more mass on, and consumed more leaf material of, wild as compared with cultivated U. molinae plants. Moreover, when applied to leaves, larvae ate more leaf material with increasing concentrations of each flavonol compound. Our study demonstrates that domestication in U. molinae reduced the amount of flavonols in leaves as well as the performance and preference of C. rudis, indicating that these compounds stimulate feeding of C. rudis. PMID:26313969

  1. A new class of flavonol-based anti-prostate cancer agents: Design, synthesis, and evaluation in cell models.

    PubMed

    Li, Xiang; Chen, Guanglin; Zhang, Xiaojie; Zhang, Qiang; Zheng, Shilong; Wang, Guangdi; Chen, Qiao-Hong

    2016-09-01

    Flavonoids are a large class of polyphenolic compounds ubiquitously distributed in dietary plants with an array of biological activities. Flavonols are a major sub-class of flavonoids featuring a hydroxyl group at C-3. Certain natural flavonols, such as quercetin and fisetin, have been shown by in vitro cell-based and in vivo animal experiments to be potential anti-prostate cancer agents. However, the Achilles' heel of flavonols as drug candidates is their moderate potency and poor pharmacokinetic profiles. This study aims to explore the substitution effect of 3-OH in flavonols on the in vitro anti-proliferative potency against both androgen-sensitive and androgen-insensitive human prostate cancer cell lines. Our first lead flavonol (3',4'-dimethoxyflavonol), eight 3-O-alkyl-3',4'-dimethoxyflavonols, and six 3-O-aminoalkyl-3',4'-dimethoxyflavonols have been synthesized through aldol condensation and the Algar-Flynn-Oyamada (AFO) reaction. The WST-1 cell proliferation assay indicates (i) that all synthesized 3-O-alkyl-3',4'-dimethoxyflavonols and 3-O-aminoalkyl-3',4'-dimethoxyflavonols are more potent than the parent 3',4'-dimethoxyflavonol and the natural flavonol quercetin in suppressing prostate cancer cell proliferation; and (ii) that incorporation of a dibutylamino group to the 3-OH group through a three- to five-carbon linker leads to the optimal derivatives with up to 292-fold enhanced potency as compared with the parent flavonol. Flow cytometry analysis showed that the most potent derivative 22 can activate PC-3 cell cycle arrest at the G2/M phase and induce PC-3 cell apoptosis. No inhibitory ability of 22 up to 50μM concentration was observed against PWR-1E normal human epithelial prostate cells, suggesting its in vitro safety profile. The results indicate that chemical modulation at 3-OH is a vital strategy to optimize flavonols as anti-prostate cancer agents. PMID:27476422

  2. Protective Role of Ternatin Anthocyanins and Quercetin Glycosides from Butterfly Pea (Clitoria ternatea Leguminosae) Blue Flower Petals against Lipopolysaccharide (LPS)-Induced Inflammation in Macrophage Cells.

    PubMed

    Nair, Vimal; Bang, Woo Young; Schreckinger, Elisa; Andarwulan, Nuri; Cisneros-Zevallos, Luis

    2015-07-22

    Twelve phenolic metabolites (nine ternatin anthocyanins and three glycosylated quercetins) were identified from the blue flowers of Clitoria ternatea by high-performance liquid chromatography diode array detection and electrospray ionization/mass spectrometry (HPLC-DAD-ESI/MS(n)). Three anthocyanins not reported in this species before show fragmentation pattern of the ternatin class. Extracts were fractionated in fractions containing flavonols (F3) and ternatin anthocyanins (F4). In general, C. ternatea polyphenols showed anti-inflammatory properties in lipopolysaccharide (LPS)-induced inflammation in RAW 264.7 macrophage cells with distinct molecular targets. Flavonols (F3) showed strong inhibition of COX-2 activity and partial ROS suppression. On the other hand, the ternatin anthocyanins (F4) inhibited nuclear NF-κB translocation, iNOS protein expression, and NO production through a non-ROS suppression mechanism. Accordingly, quercetin glycosides and ternatin anthocyanins from the blue flower petals of C. ternatea may be useful in developing drugs or nutraceuticals for protection against chronic inflammatory diseases by suppressing the excessive production of pro-inflammatory mediators from macrophage cells. PMID:26120869

  3. Protective Role of Ternatin Anthocyanins and Quercetin Glycosides from Butterfly Pea (Clitoria ternatea Leguminosae) Blue Flower Petals against Lipopolysaccharide (LPS)-Induced Inflammation in Macrophage Cells.

    PubMed

    Nair, Vimal; Bang, Woo Young; Schreckinger, Elisa; Andarwulan, Nuri; Cisneros-Zevallos, Luis

    2015-07-22

    Twelve phenolic metabolites (nine ternatin anthocyanins and three glycosylated quercetins) were identified from the blue flowers of Clitoria ternatea by high-performance liquid chromatography diode array detection and electrospray ionization/mass spectrometry (HPLC-DAD-ESI/MS(n)). Three anthocyanins not reported in this species before show fragmentation pattern of the ternatin class. Extracts were fractionated in fractions containing flavonols (F3) and ternatin anthocyanins (F4). In general, C. ternatea polyphenols showed anti-inflammatory properties in lipopolysaccharide (LPS)-induced inflammation in RAW 264.7 macrophage cells with distinct molecular targets. Flavonols (F3) showed strong inhibition of COX-2 activity and partial ROS suppression. On the other hand, the ternatin anthocyanins (F4) inhibited nuclear NF-κB translocation, iNOS protein expression, and NO production through a non-ROS suppression mechanism. Accordingly, quercetin glycosides and ternatin anthocyanins from the blue flower petals of C. ternatea may be useful in developing drugs or nutraceuticals for protection against chronic inflammatory diseases by suppressing the excessive production of pro-inflammatory mediators from macrophage cells.

  4. Energy maps for glycosidic linkage conformations.

    PubMed

    French, Alfred D

    2015-01-01

    Glycosidic linkage conformations are the main factors in determining the shapes of disaccharide, oligosaccharide, and polysaccharide molecules. The conformations are expressed in terms of the torsion angles about the bonds from each ring of the disaccharide moiety to its glycosidic oxygen atom, and the probability of a given conformation is often expressed in terms of its free or potential energy. The energy surface or map for a disaccharide is a display of the energy plotted against the two torsion angles. Successful mapping allows a particular kind of energy calculation to provide the energy values for each conformation and avoids possible pitfalls. Although different methods are discussed, the main emphasis of this chapter is on the technical production of the maps and their exploitation in further understanding the shape of the molecule in question.

  5. Phenolic glycosides from berries of Pimenta dioica.

    PubMed

    Kikuzaki, Hiroe; Miyajima, Yoshiko; Nakatani, Nobuji

    2008-05-01

    Four new phenolic glycosides, (2-hydroxy-3-methoxy-5-allyl)phenyl beta- d-(6-O-E-sinapoyl)glucopyranoside (1), (1' R,5' R)-5-(5-carboxymethyl-2-oxocyclopentyl)-3 Z-pentenyl beta-D-(6-O-galloyl)glucopyranoside (2), (S)-alpha-terpinyl [alpha-L-(2-O-galloyl)arabinofuranosyl]-(1-->6)-beta-D-glucopyranoside (3), and (R)-alpha-terpinyl [alpha-L-(2-O-galloyl)arabinofuranosyl]-(1-->6)-beta-D-glucopyranoside (4), were isolated from the berries of Pimenta dioica together with eight known flavonoids. The structures of 1-4 were elucidated on the basis of MS and NMR data and enzymatic hydrolysis. All four glycosides showed radical-scavenging activity against 1,1-diphenyl-2-picrylhydrazyl (DPPH) radicals.

  6. Hepatoprotective phenylethanoid glycosides from Cirsium setosum.

    PubMed

    Ma, Qinge; Guo, Yongming; Luo, Baomin; Liu, Wenmin; Wei, Rongrui; Yang, Chunxia; Ding, Chenghua; Xu, Xuefeng; He, Minghui

    2016-08-01

    Two new phenylethanoid glycosides, namely β-D-glucopyranoside, 1″-O-(7S)-7-(3-methoxyl-4-hydroxyphenyl)-7-methoxyethyl-3″-α-L-rhamnopyranosyl-4″-[(8E)-7-(3-methoxyl-4-hydroxyphenyl)-8-propenoate] (1) and β-D-glucopyranoside, 1″-O-(7S)-7-(3-methoxyl-4-hydroxyphenyl)-7-methoxyethyl-3″-α-L-rhamnopyranosyl-4″-[(8E)-7-(4-hydroxyphenyl)-8-propenoate] (2), together with six phenylethanoid glycosides were isolated from Cirsium setosum. Their structures were elucidated by their spectroscopic data and references. Compounds 2, 4, 5, 7 and 8 (10 μM) exhibited moderate hepatoprotective activities. Compounds (3-8) were obtained from this plant for the first time.

  7. Glucosinolates, myrosinase hydrolysis products, and flavonols found in rocket (Eruca sativa and Diplotaxis tenuifolia).

    PubMed

    Bell, Luke; Wagstaff, Carol

    2014-05-21

    Rocket species have been shown to have very high concentrations of glucosinolates and flavonols, which have numerous positive health benefits with regular consumption. This review highlights how breeders and processors of rocket species can utilize genomic and phytochemical research to improve varieties and enhance the nutritive benefits to consumers. Plant breeders are increasingly looking to new technologies such as HPLC, UPLC, LC-MS, and GC-MS to screen populations for their phytochemical content to inform plant selections. This paper collates the research that has been conducted to date in rocket and summarizes all glucosinolate and flavonol compounds identified in the species. The paper emphasizes the importance of the broad screening of populations for phytochemicals and myrosinase degradation products, as well as unique traits that may be found in underutilized gene bank resources. This review also stresses that collaboration with industrial partners is becoming essential for long-term plant breeding goals through research.

  8. A New Cucurbitane Glycoside from Siraitia grosvenorii.

    PubMed

    Chaturvedula, Venkata Sai Prakash; Meneni, Srinivasa Rao

    2015-09-01

    A systematic phytochemical study of the commercial extract of Luo Han Guo (Siraitia grosvenorii) resulted in the isolation of an additional minor new cucurbitane glycoside, mogroside V Al (1). The structure of the new compound was characterized on the basis of 1D (1H and 13C NMR) and 2D (COSY, HMQC, HMBC and NOESY) NMR and high resolution mass spectral (HRMS) data, as well as hydrolysis studies. PMID:26594748

  9. Alkyl and phenolic glycosides from Saussurea stella.

    PubMed

    Wang, Tian-Min; Wang, Ru-Feng; Chen, Hu-Biao; Shang, Ming-Ying; Cai, Shao-Qing

    2013-07-01

    One alkyl glycoside, saussurostelloside A (1), two phenolic glycosides, saussurostellosides B1 (2) and B2 (3), and 27 known compounds, including eleven flavonoids, seven phenolics, six lignans, one neolignan, one phenethyl glucoside and one fatty acid, were isolated from an ethanol extract of Saussurea stella (Asteraceae). Their structures were elucidated by NMR, MS, UV, and IR spectroscopic analysis. Of the known compounds, (+)-medioresinol-di-O-β-D-glucoside (7), picraquassioside C (10), and diosmetin-3'-O-β-D-glucoside (27) were isolated from the Asteraceae family for the first time, while (+)-pinoresinol-di-O-β-D-glucoside (6), di-O-methylcrenatin (11), protocatechuic acid (14), 1,5-di-O-caffeoylquinic acid (17), formononetin (28), and phenethyl glucoside (29) were isolated from the Saussurea genus for the first time. The anti-inflammatory activities of three new compounds (1-3), five lignans ((-)-arctiin (4), (+)-pinoresinol-4-O-β-D-glucoside (5), (+)-pinoresinol-di-O-β-D-glucoside (6), (+)-medioresinol-di-O-β-D-glucoside (7) and (+)-syringaresinol-4-O-β-D-glucoside (8)), one neolignan (picraquassioside C (10)), and one phenolic glycoside (di-O-methylcrenatin (11)) were evaluated by testing their inhibition of the release of β-glucuronidase from PAF-stimulated neutrophils. Only compound 5 showed moderate inhibition of the release of β-glucuronidase, with an inhibition ratio of 39.1%.

  10. Cloning and Characterization of a Flavonol Synthase Gene from Scutellaria baicalensis

    PubMed Central

    Kim, Yeon Bok; Kim, KwangSoo; Kim, YeJi; Tuan, Pham Anh; Kim, Haeng Hoon; Cho, Jin Woong; Park, Sang Un

    2014-01-01

    Flavonols are the most abundant of all the flavonoids and play pivotal roles in a variety of plants. We isolated a cDNA clone encoding flavonol synthase from Scutellaria baicalensis (SbFLS). The SbFLS cDNA is 1011 bp long, encodes 336 amino acid residues, and belongs to a family of 2-oxoglutarate-dependent dioxygenases. The overall structure of SbFLS is very similar to that of Arabidopsis thaliana anthocyanidin synthase (AtANS), with a β jelly-roll fold surrounded by tens of short and long α-helices. SbFLS was constitutively expressed in the roots, stems, leaves, and flowers, with particularly high expression in the roots and flowers. SbFLS transcript levels in the roots were 376-, 70-, and 2.5-fold higher than in the leaves, stems, and flowers. The myricetin content was significantly higher than that of kaempferol and quercetin. Therefore, we suggest that SbFLS mediates flavonol formation in the different organs of S. baicalensis. Our study may contribute to the knowledge of the role of FLS in S. baicalensis. PMID:24672406

  11. Flavonols, alkaloids, and antioxidant capacity of edible wild berberis species from patagonia.

    PubMed

    Ruiz, Antonieta; Zapata, Moises; Sabando, Constanza; Bustamante, Luis; von Baer, Dietrich; Vergara, Carola; Mardones, Claudia

    2014-12-24

    There are 20 species of the Berberidaceae family described in Chile, whose fruits are edible and show high anthocyanin and hydroxycinnamic acid levels. Berberis microphylla G. Forst, commonly known as calafate, is the most extensively distributed. Flavonols and alkaloids in seed, pulp, skin, and whole calafate berry extracts and other Berberis were studied using HPLC-DAD-ESI-MS/MS and HPLC with fluorescence detector. Berry samples from different locations in Chilean Patagonia, including different phenological stages, were systematically addressed. Results were compared with other organs of the plant and with other Berberis species. Total flavonol concentration in calafate (n = 65) was 1.33 ± 0.54 μmol/g. Glycosyl metabolites of quercetin and isorhamnetin were the most abundant. Similar profiles were observed in calafate from distinct locations, but important differences were observed for the other edible Berberis species. Calafate pulp and skin have higher flavonol concentrations than seeds, and the maturation process reduced its levels. TEACCUPRAC and TEACABTS of whole calafate extracts and fractions are also explored. Finally, only berberine was detected in the fruit (0.001%), mainly in seeds. Results contribute to the promotion of this berry as a superfruit from Patagonia.

  12. Functional Analysis of a Predicted Flavonol Synthase Gene Family in Arabidopsis1[W][OA

    PubMed Central

    Owens, Daniel K.; Alerding, Anne B.; Crosby, Kevin C.; Bandara, Aloka B.; Westwood, James H.; Winkel, Brenda S.J.

    2008-01-01

    The genome of Arabidopsis (Arabidopsis thaliana) contains five sequences with high similarity to FLAVONOL SYNTHASE1 (AtFLS1), a previously characterized flavonol synthase gene that plays a central role in flavonoid metabolism. This apparent redundancy suggests the possibility that Arabidopsis uses multiple isoforms of FLS with different substrate specificities to mediate the production of the flavonols, quercetin and kaempferol, in a tissue-specific and inducible manner. However, biochemical and genetic analysis of the six AtFLS sequences indicates that, although several of the members are expressed, only AtFLS1 encodes a catalytically competent protein. AtFLS1 also appears to be the only member of this group that influences flavonoid levels and the root gravitropic response in seedlings under nonstressed conditions. This study showed that the other expressed AtFLS sequences have tissue- and cell type-specific promoter activities that overlap with those of AtFLS1 and encode proteins that interact with other flavonoid enzymes in yeast two-hybrid assays. Thus, it is possible that these “pseudogenes” have alternative, noncatalytic functions that have not yet been uncovered. PMID:18467451

  13. Cloning and characterization of a flavonol synthase gene from Scutellaria baicalensis.

    PubMed

    Kim, Yeon Bok; Kim, KwangSoo; Kim, Yeji; Tuan, Pham Anh; Kim, Haeng Hoon; Cho, Jin Woong; Park, Sang Un

    2014-01-01

    Flavonols are the most abundant of all the flavonoids and play pivotal roles in a variety of plants. We isolated a cDNA clone encoding flavonol synthase from Scutellaria baicalensis (SbFLS). The SbFLS cDNA is 1011 bp long, encodes 336 amino acid residues, and belongs to a family of 2-oxoglutarate-dependent dioxygenases. The overall structure of SbFLS is very similar to that of Arabidopsis thaliana anthocyanidin synthase (AtANS), with a β jelly-roll fold surrounded by tens of short and long α-helices. SbFLS was constitutively expressed in the roots, stems, leaves, and flowers, with particularly high expression in the roots and flowers. SbFLS transcript levels in the roots were 376-, 70-, and 2.5-fold higher than in the leaves, stems, and flowers. The myricetin content was significantly higher than that of kaempferol and quercetin. Therefore, we suggest that SbFLS mediates flavonol formation in the different organs of S. baicalensis. Our study may contribute to the knowledge of the role of FLS in S. baicalensis. PMID:24672406

  14. Head-group acylation of monogalactosyldiacylglycerol is a common stress response, and the acyl-galactose acyl composition varies with the plant species and applied stress.

    PubMed

    Vu, Hieu Sy; Roth, Mary R; Tamura, Pamela; Samarakoon, Thilani; Shiva, Sunitha; Honey, Samuel; Lowe, Kaleb; Schmelz, Eric A; Williams, Todd D; Welti, Ruth

    2014-04-01

    Formation of galactose-acylated monogalactosyldiacylglycerols has been shown to be induced by leaf homogenization, mechanical wounding, avirulent bacterial infection and thawing after snap-freezing. Here, lipidomic analysis using mass spectrometry showed that galactose-acylated monogalactosyldiacylglycerols, formed in wheat (Triticum aestivum) and tomato (Solanum lycopersicum) leaves upon wounding, have acyl-galactose profiles that differ from those of wounded Arabidopsis thaliana, indicating that different plant species accumulate different acyl-galactose components in response to the same stress. Additionally, the composition of the acyl-galactose component of Arabidopsis acMGDG (galactose-acylated monogalactosyldiacylglycerol) depends on the stress treatment. After sub-lethal freezing treatment, acMGDG contained mainly non-oxidized fatty acids esterified to galactose, whereas mostly oxidized fatty acids accumulated on galactose after wounding or bacterial infection. Compositional data are consistent with acMGDG being formed in vivo by transacylation with fatty acids from digalactosyldiacylglycerols. Oxophytodienoic acid, an oxidized fatty acid, was more concentrated on the galactosyl ring of acylated monogalactosyldiacylglycerols than in galactolipids in general. Also, oxidized fatty acid-containing acylated monogalactosyldiacylglycerols increased cumulatively when wounded Arabidopsis leaves were wounded again. These findings suggest that, in Arabidopsis, the pool of galactose-acylated monogalactosyldiacylglycerols may serve to sequester oxidized fatty acids during stress responses. PMID:24286212

  15. The Identification of Perillyl Alcohol Glycosides with Improved Antiproliferative Activity

    PubMed Central

    2015-01-01

    A facile route to perillyl alcohol (POH) differential glycosylation and the corresponding synthesis of a set of 34 POH glycosides is reported. Subsequent in vitro studies revealed a sugar dependent antiproliferative activity and the inhibition of S6 ribosomal protein phosphorylation as a putative mechanism of representative POH glycosides. The most active glycoside from this cumulative study (4′-azido-d-glucoside, PG9) represents one of the most cytotoxic POH analogues reported to date. PMID:25121720

  16. Steroidal glycosides from Furcraea foetida and their cytotoxic activity.

    PubMed

    Yokosuka, Akihito; Sano, Tomoe; Hashimoto, Ken; Sakagami, Hiroshi; Mimaki, Yoshihiro

    2009-10-01

    Two new spirostanol glycosides (1, 2) and a new furostanol glycoside (3), together with nine known steroidal glycosides (4-12) were isolated from the leaves of Furcraea foetida (Agavaceae). The structures of the new compounds were determined by spectroscopic analysis and the results of hydrolytic cleavage. The isolated compounds were evaluated for their cytotoxic activities against HL-60 human leukemia cells, A549 human lung adenocarcinoma cells, HSC-2 human oral squamous carcinoma cells, and HSC-4 human oral squamous carcinoma cells.

  17. Facile access to new C-glycosides and C-glycoside scaffolds incorporating functionalised aromatic moieties.

    PubMed

    Redpath, Philip; Ness, Kerry A; Rousseau, Joanne; Macdonald, Simon J F; Migaud, Marie E

    2015-01-30

    The tandem ene/intramolecular Sakurai cyclisation (IMSC) reaction has been successfully applied to the synthesis of a range of C-glycosides, with key intermediates offering opportunities for functionalisation of the glycon moiety. To demonstrate the versatility of the approach to access the 2-deoxy-C-glycoside series, we synthesised diastereomerically pure C-glucoside and galactoside derivatives incorporating functionalised aromatic, heteroaromatic and bicyclic aromatic moieties, in addition to the C-homologue of (±)-β-2-deoxy-glucose 6-phosphate. PMID:25486220

  18. A sensitive method for the detection and quantification of ginkgo flavonols from plasma.

    PubMed

    Zhao, Yang; Wang, Li; Bao, Yuanwu; Li, Chuan

    2007-01-01

    Extracts from Ginkgo biloba leaves (family Ginkgoaceae) have antioxidant and free radical scavenging effects, largely attributed to the flavonols, which are a major class of functional components in ginkgo extracts. In order to facilitate analysis of systemic exposure to ginkgo-derived products in animals and/or humans, we developed a liquid chromatography/tandem mass spectrometry (LC/MS/MS)-based method that is capable of routinely monitoring plasma levels of ginkgo flavonols. We used an initial acidic hydrolysis step to convert the plasma ginkgo flavonol conjugates into their aglycone forms [quercetin (QCT), kaempferol (KMF) and isorhamnetin (ISR)] prior to EtOAc-based extraction and subsequent LC/MS/MS-based analysis. Comparative studies showed that the use of a mobile phase containing an extremely low concentration of HCOOH (0.01 per thousand) dramatically improved the electrospray ionization efficiency of the analytes in the negative ion mode; the efficiencies were approximately 4-, approximately 8- and approximately 20-fold higher for QCT, KMF and ISR, respectively, versus the results obtained using an electrolyte-free mobile phase, or approximately 2-, approximately 3- and approximately 4-fold higher, respectively, versus the results obtained using a mobile phase containing the more commonly utilized concentration of HCOOH (1 per thousand). In addition, use of the low concentration of HCOOH also decreased undesired matrix effects. These favorable effects have been referred to as 'LC-electrolyte effects'. Due to structural differences in the B-ring substituent, different types of precursor-to-product ion pairs (m/z 301 --> 151 for QCT, 285 --> 187 for KMF, and 315 --> 300 for ISR) were used for the selected reaction monitoring of the analytes. In addition, the chromatographic conditions were optimized on the basis of an initial scouting of matrix effects on analyte ionization. Despite the absence of an internal standard, the validation results consistently

  19. Acylated but not des-acyl ghrelin is neuroprotective in an MPTP mouse model of Parkinson's disease.

    PubMed

    Bayliss, Jacqueline A; Lemus, Moyra; Santos, Vanessa V; Deo, Minh; Elsworth, John D; Andrews, Zane B

    2016-05-01

    The gut hormone ghrelin is widely beneficial in many disease states. However, ghrelin exists in two distinctive isoforms, each with its own metabolic profile. In Parkinson's Disease (PD) acylated ghrelin administration is neuroprotective, however, the role of des-acylated ghrelin remains unknown. In this study, we wanted to identify the relative contribution each isoform plays using the MPTP model of PD. Chronic administration of acylated ghrelin in mice lacking both isoforms of ghrelin (Ghrelin KO) attenuated the MPTP-induced loss on tyrosine hydroxylase (TH) neuronal number and volume and TH protein expression in the nigrostriatal pathway. Moreover, acylated ghrelin reduced the increase in glial fibrillary acidic protein and Ionized calcium binding adaptor molecule 1 microglia in the substantia nigra. However, injection of acylated ghrelin also elevated plasma des-acylated ghrelin, indicating in vivo deacetylation. Next, we chronically administered des-acylated ghrelin to Ghrelin KO mice and observed no neuroprotective effects in terms of TH cell number, TH protein expression, glial fibrillary acidic protein and ionized calcium binding adaptor molecule 1 cell number. The lack of a protective effect was mirrored in ghrelin-O-acyltransferase KO mice, which lack the ability to acylate ghrelin and consequently these mice have chronically increased plasma des-acyl ghrelin. Plasma corticosterone was elevated in ghrelin-O-acyltransferase KO mice and with des-acylated ghrelin administration. Overall, our studies suggest that acylated ghrelin is the isoform responsible for in vivo neuroprotection and that pharmacological approaches preventing plasma conversion from acyl ghrelin to des-acyl ghrelin may have clinical efficacy to help slow or prevent the debilitating effects of PD. Ghrelin exists in the plasma as acyl and des-acyl ghrelin. We determined the form responsible for in vivo neuroprotection in a mouse model of Parkinson's disease. Although exogenous acyl ghrelin

  20. Acyl glucuronides: the good, the bad and the ugly.

    PubMed

    Regan, Sophie L; Maggs, James L; Hammond, Thomas G; Lambert, Craig; Williams, Dominic P; Park, B Kevin

    2010-10-01

    Acyl glucuronidation is the major metabolic conjugation reaction of most carboxylic acid drugs in mammals. The physiological consequences of this biotransformation have been investigated incompletely but include effects on drug metabolism, protein binding, distribution and clearance that impact upon pharmacological and toxicological outcomes. In marked contrast, the exceptional but widely disparate chemical reactivity of acyl glucuronides has attracted far greater attention. Specifically, the complex transacylation and glycation reactions with proteins have provoked much inconclusive debate over the safety of drugs metabolised to acyl glucuronides. It has been hypothesised that these covalent modifications could initiate idiosyncratic adverse drug reactions. However, despite a large body of in vitro data on the reactions of acyl glucuronides with protein, evidence for adduct formation from acyl glucuronides in vivo is limited and potentially ambiguous. The causal connection of protein adduction to adverse drug reactions remains uncertain. This review has assessed the intrinsic reactivity, metabolic stability and pharmacokinetic properties of acyl glucuronides in the context of physiological, pharmacological and toxicological perspectives. Although numerous experiments have characterised the reactions of acyl glucuronides with proteins, these might be attenuated substantially in vivo by rapid clearance of the conjugates. Consequently, to delineate a relationship between acyl glucuronide formation and toxicological phenomena, detailed pharmacokinetic analysis of systemic exposure to the acyl glucuronide should be undertaken adjacent to determining protein adduct concentrations in vivo. Further investigation is required to ascertain whether acyl glucuronide clearance is sufficient to prevent covalent modification of endogenous proteins and consequentially a potential immunological response. PMID:20830700

  1. Determination of Flavonol Aglycones in Ginkgo biloba Dietary Supplement Crude Materials and Finished Products by High-Performance Liquid Chromatography: Single Laboratory Validation

    PubMed Central

    Gray, Dean; LeVanseler, Kerri; Pan, Meide

    2008-01-01

    A single laboratory validation (SLV) was completed for a method to determine the flavonol aglycones quercetin, kaempferol, and isorhamnetin in Ginkgo biloba products. The method calculates total glycosides based on these aglycones formed following acid hydrolysis. Nine matrixes were chosen for the study, including crude leaf material, standardized dry powder extract, single and multiple entity finished products, and ethanol and glycerol tinctures. For the 9 matrixes evaluated as part of this SLV, the method appeared to be selective and specific, with no observed interferences. The simplified 60 min oven heating hydrolysis procedure was effective for each of the matrixes studied, with no apparent or consistent differences between 60, 75, and 90 min at 90°C. A Youden ruggedness trial testing 7 factors with the potential to affect quantitative results showed that 2 factors (volume hydrolyzed and test sample extraction/hydrolysis weight) were the most important parameters for control during sample preparation. The method performed well in terms of precision, with 4 matrixes tested in triplicate over a 3-day period showing an overall repeatability (relative standard deviation, RSD) of 2.3%. Analysis of variance testing at α = 0.05 showed no significant differences among the within- or between-group sources of variation, although comparisons of within-day (Sw), between-day (Sb), and total (St) precision showed that a majority of the standard deviation came from within-day determinations for all matrixes. Accuracy testing at 2 levels (approximately 30 and 90% of the determined concentrations in standardized dry powder extract) from 2 complex negative control matrixes showed an overall 96% recovery and RSD of 1.0% for the high spike, and 94% recovery and RSD of 2.5% for the low spike. HorRat scores were within the limits for performance acceptability, ranging from 0.4 to 1.3. Based on the performance results presented herein, it is recommended that this method progress

  2. Determination of flavonol aglycones in Ginkgo biloba dietary supplement crude materials and finished products by high-performance liquid chromatography: single laboratory validation.

    PubMed

    Gray, Dean; LeVanseler, Kerri; Pan, Meide

    2005-01-01

    A single laboratory validation (SLV) was completed for a method to determine the flavonol aglycones quercetin, kaempferol, and isorhamnetin in Ginkgo biloba products. The method calculates total glycosides based on these aglycones formed following acid hydrolysis. Nine matrixes were chosen for the study, including crude leaf material, standardized dry powder extract, single and multiple entity finished products, and ethanol and glycerol tinctures. For the 9 matrixes evaluated as part of this SLV, the method appeared to be selective and specific, with no observed interferences. The simplified 60 min oven heating hydrolysis procedure was effective for each of the matrixes studied, with no apparent or consistent differences between 60, 75, and 90 min at 90 degrees C. A Youden ruggedness trial testing 7 factors with the potential to affect quantitative results showed that 2 factors (volume hydrolyzed and test sample extraction/hydrolysis weight) were the most important parameters for control during sample preparation. The method performed well in terms of precision, with 4 matrixes tested in triplicate over a 3-day period showing an overall repeatability (relative standard deviation, RSD) of 2.3%. Analysis of variance testing at alpha = 0.05 showed no significant differences among the within- or between-group sources of variation, although comparisons of within-day (Sw), between-day (Sb), and total (St) precision showed that a majority of the standard deviation came from within-day determinations for all matrixes. Accuracy testing at 2 levels (approximately 30 and 90% of the determined concentrations in standardized dry powder extract) from 2 complex negative control matrixes showed an overall 96% recovery and RSD of 1.0% for the high spike, and 94% recovery and RSD of 2.5% for the low spike. HorRat scores were within the limits for performance acceptability, ranging from 0.4 to 1.3. Based on the performance results presented herein, it is recommended that this method

  3. Post-transcriptional silencing of flavonol synthase mRNA in tobacco leads to fruits with arrested seed set.

    PubMed

    Mahajan, Monika; Ahuja, Paramvir Singh; Yadav, Sudesh Kumar

    2011-01-01

    Flavonoids are synthesized by phenylpropanoid pathway. They are known to participate in large number of physiological and biochemical processes in plants. Parthenocarpy and male sterility has earlier been reported by silencing chalcone synthase (CHS) encoding gene. Silencing of CHS has blocked the synthesis of most of useful flavonoids including flavan-3-ols and flavonols. Also, these studies could not identify whether parthenocarpy/male sterility were due to lack of flavan-3-ols or flavonols or both. Flavonol synthase (FLS) is an important enzyme of flavonoid pathway that catalyzes the formation of flavonols. In this article, we propose a novel strategy towards the generation of seedless or less-seeded fruits by downregulation of flavonol biosynthesis in tobacco (Nicotiana tabacum cv Xanthi) through post-transcriptional gene silencing (PTGS) of FLS encoding mRNA. The FLS silenced lines were observed for 20-80% reduction in FLS encoding gene expression and 25-93% reduction in flavonol (quercetin) content. Interestingly, these FLS silenced tobacco lines also showed reduction in their anthocyanidins content. While the content of flavan-3-ols (catechin, epi-catechin and epi-gallocatechin) was found to be increased in FLS silenced lines. The delayed flowering in FLS silenced lines could be due to decrease in level of indole acetic acid (IAA) at apical region of their shoots. Furthermore, the pollen germination was hampered and pollens were unable to produce functional pollen tube in FLS silenced tobacco lines. Pods of FLS silenced lines contained significantly less number of seeds. The in vitro and in vivo studies where 1 µM quercetin was supplied to germination media, documented the restoration of normal pollen germination and pollen tube growth. This finding identified the role of flavonols particularly quercetin in pollen germination as well as in the regulation of plant fertility. Results also suggest a novel approach towards generation of seedless

  4. Head-group acylation of monogalactosyldiacylglycerol is a common stress response, and the acyl-galactose acyl composition varies with the plant species and applied stress

    PubMed Central

    Vu, Hieu Sy; Roth, Mary R.; Tamura, Pamela; Samarakoon, Thilani; Shiva, Sunitha; Honey, Samuel; Lowe, Kaleb; Schmelz, Eric A.; Williams, Todd D.; Welti, Ruth

    2014-01-01

    Formation of galactose-acylated monogalactosyldiacylglycerols has been shown to be induced by leaf homogenization, mechanical wounding, avirulent bacterial infection, and thawing after snap-freezing. Here, lipidomic analysis using mass spectrometry showed that galactose-acylated monogalactosyldiacylglycerols, formed in wheat (Triticum aestivum) and tomato (Solanum lycopersicum) leaves upon wounding, have acyl-galactose profiles that differ from those of wounded Arabidopsis thaliana, indicating that different plant species accumulate different acyl-galactose components in response to the same stress. Additionally, the composition of the acyl-galactose component of Arabidopsis acMGDG depends on the stress treatment. After sub-lethal freezing treatment, acMGDG contained mainly non-oxidized fatty acids esterified to galactose, whereas mostly oxidized fatty acids accumulated on galactose after wounding or bacterial infection. Compositional data are consistent with acMGDG being formed in vivo by transacylation with fatty acids from digalactosyldiacylglycerols. Oxophytodienoic acid, an oxidized fatty acid, was more concentrated on the galactosyl ring of acylated monogalactosyldiacylglycerols than in galactolipids in general. Also, oxidized fatty acid-containing acylated monogalactosyldiacylglycerols increased cumulatively when wounded Arabidopsis leaves were wounded again. These findings suggest that, in Arabidopsis, the pool of galactose-acylated monogalactosyldiacylglycerols may serve to sequester oxidized fatty acids during stress responses. PMID:24286212

  5. 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.

  6. Physiological Consequences of Compartmentalized Acyl-CoA Metabolism*

    PubMed Central

    Cooper, Daniel E.; Young, Pamela A.; Klett, Eric L.; Coleman, Rosalind A.

    2015-01-01

    Meeting the complex physiological demands of mammalian life requires strict control of the metabolism of long-chain fatty acyl-CoAs because of the multiplicity of their cellular functions. Acyl-CoAs are substrates for energy production; stored within lipid droplets as triacylglycerol, cholesterol esters, and retinol esters; esterified to form membrane phospholipids; or used to activate transcriptional and signaling pathways. Indirect evidence suggests that acyl-CoAs do not wander freely within cells, but instead, are channeled into specific pathways. In this review, we will discuss the evidence for acyl-CoA compartmentalization, highlight the key modes of acyl-CoA regulation, and diagram potential mechanisms for controlling acyl-CoA partitioning. PMID:26124277

  7. A new phenylpropanoid glycoside from Cirsium setosum.

    PubMed

    Ke, Rui; Zhu, En-Yuan; Chou, Gui-xin

    2010-07-01

    To study the chemical constituents of Cirsium setosum (Willd.) MB., 70% ethanol extract of the aerial parts was subjected to column chromatography. One new phenylpropanoid glycoside, sinapyl alcohol 9-O-(E)-p-coumaroyl-4-O-beta-D-glucopyanoside (1) was isolated, along with three known compounds: lycoperodine-1 (2), apigenin-7-O-(6"-(E)-p-coumaroyl)-beta-D-galactopyranoside (3) and quercetin (4). The structures were elucidated on the basis of spectral and chemical evidence. Compound 2 was obtained from Cirsium genus for the first time, compounds 3 and 4 were obtained from this plant for the first time.

  8. Two pentasaccharide resin glycosides from Argyreia acuta.

    PubMed

    Yin, Yong-Qin; Pan, Jie-Tao; Yu, Bang-Wei; Cui, Hong-Hua; Yan, You-Shao; Chen, Yan-Fen

    2016-01-01

    Two new compounds of acutacosides 1 and 2, pentasaccharide resin glycosides were isolated from the aerial parts of Argyreia acuta. The core of the two compounds was operculinic acid A, and they were esterfied at the same position, just one substituent group was linked at C-2 of Rha. The absolute configuration of the aglycone in the two compounds was established by Mosher's method, which was (11S)-hydroxyhexadecanoic acid (jalapinolic acid). Their structures were established by a combination of spectroscopic and chemical methods.

  9. Two pentasaccharide resin glycosides from Argyreia acuta.

    PubMed

    Yin, Yong-Qin; Pan, Jie-Tao; Yu, Bang-Wei; Cui, Hong-Hua; Yan, You-Shao; Chen, Yan-Fen

    2016-01-01

    Two new compounds of acutacosides 1 and 2, pentasaccharide resin glycosides were isolated from the aerial parts of Argyreia acuta. The core of the two compounds was operculinic acid A, and they were esterfied at the same position, just one substituent group was linked at C-2 of Rha. The absolute configuration of the aglycone in the two compounds was established by Mosher's method, which was (11S)-hydroxyhexadecanoic acid (jalapinolic acid). Their structures were established by a combination of spectroscopic and chemical methods. PMID:25925631

  10. Characterization of a Citrus R2R3-MYB Transcription Factor that Regulates the Flavonol and Hydroxycinnamic Acid Biosynthesis.

    PubMed

    Liu, Chaoyang; Long, Jianmei; Zhu, Kaijie; Liu, Linlin; Yang, Wei; Zhang, Hongyan; Li, Li; Xu, Qiang; Deng, Xiuxin

    2016-01-01

    Flavonols and hydroxycinnamic acids are important phenylpropanoid metabolites in plants. In this study, we isolated and characterized a citrus R2R3-MYB transcription factor CsMYBF1, encoding a protein belonging to the flavonol-specific MYB subgroup. Ectopic expression of CsMYBF1 in tomato led to an up-regulation of a series of genes involved in primary metabolism and the phenylpropanoid pathway, and induced a strong accumulation of hydroxycinnamic acid compounds but not the flavonols. The RNAi suppression of CsMYBF1 in citrus callus caused a down-regulation of many phenylpropanoid pathway genes and reduced the contents of hydroxycinnamic acids and flavonols. Transactivation assays indicated that CsMYBF1 activated several promoters of phenylpropanoid pathway genes in tomato and citrus. Interestingly, CsMYBF1 could activate the CHS gene promoter in citrus, but not in tomato. Further examinations revealed that the MYBPLANT cis-elements were essential for CsMYBF1 in activating phenylpropanoid pathway genes. In summary, our data indicated that CsMYBF1 possessed the function in controlling the flavonol and hydroxycinnamic acid biosynthesis, and the regulatory differences in the target metabolite accumulation between two species may be due to the differential activation of CHS promoters by CsMYBF1. Therefore, CsMYBF1 constitutes an important gene source for the engineering of specific phenylpropanoid components. PMID:27162196

  11. The Balance of Expression of Dihydroflavonol 4-reductase and Flavonol Synthase Regulates Flavonoid Biosynthesis and Red Foliage Coloration in Crabapples.

    PubMed

    Tian, Ji; Han, Zhen-yun; Zhang, Jie; Hu, YuJing; Song, Tingting; Yao, Yuncong

    2015-01-01

    Red leaf color is an attractive trait of Malus families, including crabapple (Malus spp.); however, little is known about the molecular mechanisms that regulate the coloration. Dihydroflavonols are intermediates in the production of both colored anthocyanins and colorless flavonols, and this current study focused on the gene expression balance involved in the relative accumulation of these compounds in crabapple leaves. Levels of anthocyanins and the transcript abundances of the anthocyanin biosynthetic gene, dihydroflavonol 4-reductase (McDFR) and the flavonol biosynthetic gene, flavonol synthase (McFLS), were assessed during the leaf development in two crabapple cultivars, 'Royalty' and 'Flame'. The concentrations of anthocyanins and flavonols correlated with leaf color and we propose that the expression of McDFR and McFLS influences their accumulation. Further studies showed that overexpression of McDFR, or silencing of McFLS, increased anthocyanin production, resulting in red-leaf and red fruit peel phenotypes. Conversely, elevated flavonol production and green phenotypes in crabapple leaves and apple peel were observed when McFLS was overexpressed or McDFR was silenced. These results suggest that the relative activities of McDFR and McFLS are important determinants of the red color of crabapple leaves, via the regulation of the metabolic fate of substrates that these enzymes have in common. PMID:26192267

  12. The Balance of Expression of Dihydroflavonol 4-reductase and Flavonol Synthase Regulates Flavonoid Biosynthesis and Red Foliage Coloration in Crabapples

    PubMed Central

    Tian, Ji; Han, Zhen-yun; Zhang, Jie; Hu, YuJing; Song, Tingting; Yao, Yuncong

    2015-01-01

    Red leaf color is an attractive trait of Malus families, including crabapple (Malus spp.); however, little is known about the molecular mechanisms that regulate the coloration. Dihydroflavonols are intermediates in the production of both colored anthocyanins and colorless flavonols, and this current study focused on the gene expression balance involved in the relative accumulation of these compounds in crabapple leaves. Levels of anthocyanins and the transcript abundances of the anthocyanin biosynthetic gene, dihydroflavonol 4-reductase (McDFR) and the flavonol biosynthetic gene, flavonol synthase (McFLS), were assessed during the leaf development in two crabapple cultivars, ‘Royalty’ and ‘Flame’. The concentrations of anthocyanins and flavonols correlated with leaf color and we propose that the expression of McDFR and McFLS influences their accumulation. Further studies showed that overexpression of McDFR, or silencing of McFLS, increased anthocyanin production, resulting in red-leaf and red fruit peel phenotypes. Conversely, elevated flavonol production and green phenotypes in crabapple leaves and apple peel were observed when McFLS was overexpressed or McDFR was silenced. These results suggest that the relative activities of McDFR and McFLS are important determinants of the red color of crabapple leaves, via the regulation of the metabolic fate of substrates that these enzymes have in common. PMID:26192267

  13. Characterization of a Citrus R2R3-MYB Transcription Factor that Regulates the Flavonol and Hydroxycinnamic Acid Biosynthesis

    PubMed Central

    Liu, Chaoyang; Long, Jianmei; Zhu, Kaijie; Liu, Linlin; Yang, Wei; Zhang, Hongyan; Li, Li; Xu, Qiang; Deng, Xiuxin

    2016-01-01

    Flavonols and hydroxycinnamic acids are important phenylpropanoid metabolites in plants. In this study, we isolated and characterized a citrus R2R3-MYB transcription factor CsMYBF1, encoding a protein belonging to the flavonol-specific MYB subgroup. Ectopic expression of CsMYBF1 in tomato led to an up-regulation of a series of genes involved in primary metabolism and the phenylpropanoid pathway, and induced a strong accumulation of hydroxycinnamic acid compounds but not the flavonols. The RNAi suppression of CsMYBF1 in citrus callus caused a down-regulation of many phenylpropanoid pathway genes and reduced the contents of hydroxycinnamic acids and flavonols. Transactivation assays indicated that CsMYBF1 activated several promoters of phenylpropanoid pathway genes in tomato and citrus. Interestingly, CsMYBF1 could activate the CHS gene promoter in citrus, but not in tomato. Further examinations revealed that the MYBPLANT cis-elements were essential for CsMYBF1 in activating phenylpropanoid pathway genes. In summary, our data indicated that CsMYBF1 possessed the function in controlling the flavonol and hydroxycinnamic acid biosynthesis, and the regulatory differences in the target metabolite accumulation between two species may be due to the differential activation of CHS promoters by CsMYBF1. Therefore, CsMYBF1 constitutes an important gene source for the engineering of specific phenylpropanoid components. PMID:27162196

  14. Characterization of a Citrus R2R3-MYB Transcription Factor that Regulates the Flavonol and Hydroxycinnamic Acid Biosynthesis.

    PubMed

    Liu, Chaoyang; Long, Jianmei; Zhu, Kaijie; Liu, Linlin; Yang, Wei; Zhang, Hongyan; Li, Li; Xu, Qiang; Deng, Xiuxin

    2016-05-10

    Flavonols and hydroxycinnamic acids are important phenylpropanoid metabolites in plants. In this study, we isolated and characterized a citrus R2R3-MYB transcription factor CsMYBF1, encoding a protein belonging to the flavonol-specific MYB subgroup. Ectopic expression of CsMYBF1 in tomato led to an up-regulation of a series of genes involved in primary metabolism and the phenylpropanoid pathway, and induced a strong accumulation of hydroxycinnamic acid compounds but not the flavonols. The RNAi suppression of CsMYBF1 in citrus callus caused a down-regulation of many phenylpropanoid pathway genes and reduced the contents of hydroxycinnamic acids and flavonols. Transactivation assays indicated that CsMYBF1 activated several promoters of phenylpropanoid pathway genes in tomato and citrus. Interestingly, CsMYBF1 could activate the CHS gene promoter in citrus, but not in tomato. Further examinations revealed that the MYBPLANT cis-elements were essential for CsMYBF1 in activating phenylpropanoid pathway genes. In summary, our data indicated that CsMYBF1 possessed the function in controlling the flavonol and hydroxycinnamic acid biosynthesis, and the regulatory differences in the target metabolite accumulation between two species may be due to the differential activation of CHS promoters by CsMYBF1. Therefore, CsMYBF1 constitutes an important gene source for the engineering of specific phenylpropanoid components.

  15. Triterpene glycosides from the cultures of Phytolacca americana.

    PubMed

    Takahashi, H; Namikawa, Y; Tanaka, M; Fukuyama, Y

    2001-02-01

    A new triterpene glycoside I was isolated together with the five known triterpene glycosides 2-6 from the cultures of Phytolacca americana. The structure of 1 was elucidated by analysis of spectroscopic data and comparison of its NMR data with those of 2-7 and chemical degradation.

  16. Bioavailability of the flavonol quercetin in cows after intraruminal application of quercetin aglycone and rutin.

    PubMed

    Berger, L M; Wein, S; Blank, R; Metges, C C; Wolffram, S

    2012-09-01

    The bioavailability of quercetin has been intensively investigated in monogastric species, but knowledge about its bioavailability in ruminants does not exist. Thus, the aim of the present study was to determine the bioavailability of quercetin in nonlactating cows equipped with indwelling catheters placed in one jugular vein after intraruminal and additionally after i.v. application, respectively. Quercetin was administered intraruminally in equimolar amounts, either in the aglycone form or as its glucorhamnoside rutin, each at 2 dosages [10 and 50 mg of quercetin/kg of body weight (BW)]. In a second trial, 0.8 mg of quercetin aglycone/kg of BW was applied i.v. Blood samples were drawn 0.5, 1, 1.5, 2, 2.5, 3, 4, 6, 8, 12, and 24 h after intraruminal application and every 5 min (first hour), every 10 min(second hour), and at 3 and 6h after i.v. bolus application, respectively. Quercetin and quercetin metabolites with an intact flavonol structure (isorhamnetin, tamarixetin, and kaempferol) in plasma samples were analyzed by HPLC with fluorescence detection. After intraruminal application of quercetin and rutin, respectively, quercetin and its methylated (isorhamnetin, tamarixetin) and dehydroxylated (kaempferol) derivatives were present in plasma mainly as conjugated forms, whereas free quercetin and its derivatives were scarcely detected. For rutin, the relative bioavailability of total flavonols (sum of conjugated and nonconjugated quercetin and its conjugated and nonconjugated derivatives after intake of 50 mg/kg of BW) was 767.3% compared with quercetin aglycone (100%). Absolute bioavailability of total flavonols was only 0.1 and 0.5% after quercetin aglycone and rutin applications, respectively. Our data demonstrate that bioavailability of quercetin from rutin is substantially higher compared with that from quercetin aglycone in cows after intraruminal (or oral) application, unlike in monogastric species. PMID:22916908

  17. Attenuation of airway smooth muscle contractility via flavonol-mediated inhibition of phospholipase-Cβ.

    PubMed

    Brown, Amy; Danielsson, Jennifer; Townsend, Elizabeth A; Zhang, Yi; Perez-Zoghbi, Jose F; Emala, Charles W; Gallos, George

    2016-04-15

    Enhanced contractility of airway smooth muscle (ASM) is a major pathophysiological characteristic of asthma. Expanding the therapeutic armamentarium beyond β-agonists that target ASM hypercontractility would substantially improve treatment options. Recent studies have identified naturally occurring phytochemicals as candidates for acute ASM relaxation. Several flavonoids were evaluated for their ability to acutely relax human and murine ASM ex vivo and murine airways in vivo and were evaluated for their ability to inhibit procontractile signaling pathways in human ASM (hASM) cells. Two members of the flavonol subfamily, galangin and fisetin, significantly relaxed acetylcholine-precontracted murine tracheal rings ex vivo (n = 4 and n = 5, respectively, P < 0.001). Galangin and fisetin also relaxed acetylcholine-precontracted hASM strips ex vivo (n = 6-8, P < 0.001). Functional respiratory in vivo murine studies demonstrated that inhaled galangin attenuated the increase in lung resistance induced by inhaled methacholine (n = 6, P < 0.01). Both flavonols, galangin and fisetin, significantly inhibited purified phosphodiesterase-4 (PDE4) (n = 7, P < 0.05; n = 7, P < 0.05, respectively), and PLCβ enzymes (n = 6, P < 0.001 and n = 6, P < 0.001, respectively) attenuated procontractile Gq agonists' increase in intracellular calcium (n = 11, P < 0.001), acetylcholine-induced increases in inositol phosphates, and CPI-17 phosphorylation (n = 9, P < 0.01) in hASM cells. The prorelaxant effect retained in these structurally similar flavonols provides a novel pharmacological method for dual inhibition of PLCβ and PDE4 and therefore may serve as a potential treatment option for acute ASM constriction.

  18. Enzymatic synthesis of epothilone A glycosides

    PubMed Central

    2014-01-01

    Epothilones are extremely cytotoxic chemotherapeutic agents with epoxide, thiazole, and ketone groups that share equipotent kinetic similarity with taxol. The in vitro glycosylation catalyzed by uridine diphosphate glucosyltransferase (YjiC) from Bacillus licheniformis generated six novel epothilone A glycoside analouges including epothilone A 7-O-β-D-glucoside, epothilone A 7-O-β-D-galactoside, epothilone A 3,7-O-β-D-digalactoside, epothilone A 7-O-β-D-2-deoxyglucoside, epothilone A 7-O-β-L-rhamnoside, and epothilone A 7-O-β-L-fucoside. Epothilone A 7-O-β-D-glucoside was structurally elucidated by ultra-high performance liquid chromatography-photo diode array (UPLC-PDA) conjugated with high resolution quantitative time-of-flight-electrospray ionization mass spectroscopy (HR-QTOF ESI-MS/MS) supported by one-and two-dimensional nuclear magnetic resonance studies whereas other epothilone A glycosides were characterized by UPLC-PDA and HR-QTOF ESI-MS/MS analyses. The time dependent conversion study of epothilone A to epothilone A 7-O-β-D-glucoside found to be maximum (~26%) between 3 h to 5 h incubation. PMID:24949266

  19. Flavonol dimers from callus cultures of Dysosma versipellis and their in vitro neuraminidase inhibitory activities.

    PubMed

    Chen, Ridao; Duan, Ruigang; Wei, Yannan; Zou, Jianhua; Li, Junwei; Liu, Xiaoyue; Wang, Haiyan; Guo, Ying; Li, Qiuhong; Dai, Jungui

    2015-12-01

    A chemical investigation of callus cultures of Dysosma versipellis led to the isolation of five new flavonol dimers, dysoverines A-E (1-5), together with 12 known compounds (6-17). The structures of new compounds were determined by the extensive spectroscopic data analyses. The biosynthetic pathway of the new compounds was proposed to involve O-methylation, prenylation, and Diels-Alder cycloaddition, which successively occurred in cultured plant cells. Compounds 1-17 exhibited in vitro neuraminidase inhibitory activities with the IC50 values of 31.0-93.9μM. PMID:26481138

  20. A new flavonol glucoside from the aerial parts of Sida glutinosa.

    PubMed

    Das, Niranjan; Achari, Basudev; Harigaya, Yoshihiro; Dinda, Biswanath

    2011-10-01

    Phytochemical investigation on the dried aerial parts of Sida glutinosa has led to the isolation of a new flavonol glucoside, glutinoside (1), along with seven known compounds, 24(28)-dehydromakisterone A (2), 1,2,3,9-tetrahydropyrrolo[2,1-b]-quinazolin-3-amine (3), docosanoic acid, 1-triacontanol, campesterol, stigmasterol, and β-sitosterol. The structures of these compounds were elucidated by means of extensive spectroscopic techniques as well as GC/MS analysis (for sterols) and comparison with the literature data. All these seven known compounds are reported from this plant for the first time.

  1. Ultra(high)-pressure liquid chromatography-electrospray ionization-time-of-flight-ion mobility-high definition mass spectrometry for the rapid identification and structural characterization of flavonoid glycosides from cauliflower waste.

    PubMed

    Gonzales, Gerard Bryan; Raes, Katleen; Coelus, Sofie; Struijs, Karin; Smagghe, Guy; Van Camp, John

    2014-01-01

    In this paper, a strategy for the detection and structural elucidation of flavonoid glycosides from a complex matrix in a single chromatographic run using U(H)PLC-ESI-IMS-HDMS/MS(E) is presented. This system operates using alternative low and high energy voltages that is able to perform the task of conventional MS/MS in a data-independent way without re-injection of the sample, which saves analytical time. Also, ion mobility separation (IMS) was employed as an additional separation technique for compounds that are co-eluting after U(H)PLC separation. First, the fragmentation of flavonoid standards were analyzed and criteria was set for structural elucidation of flavonoids in a plant extract. Based on retention times, UV spectra, exact mass, and MS fragment characteristics, such as abundances of daughter ions and the presence of radical ions ([Y0-H](-)), a total 19 flavonoid glycosides, of which 8 non-acylated and 11 acylated, were detected and structurally characterized in a cauliflower waste extract. Kaempferol and quercetin were the main aglycones detected while sinapic and ferulic acid were the main phenolic acids. C-glycosides were also found although their structure could not be elucidated. The proposed method can be used as a rapid screening test for flavonoid identification and for routine analysis of plant extracts, such as these derived from cauliflower waste. The study also confirms that agroindustrial wastes, such as cauliflower leaves, could be seen as a valuable source of different bioactive phenolic compounds.

  2. Ultra(high)-pressure liquid chromatography-electrospray ionization-time-of-flight-ion mobility-high definition mass spectrometry for the rapid identification and structural characterization of flavonoid glycosides from cauliflower waste.

    PubMed

    Gonzales, Gerard Bryan; Raes, Katleen; Coelus, Sofie; Struijs, Karin; Smagghe, Guy; Van Camp, John

    2014-01-01

    In this paper, a strategy for the detection and structural elucidation of flavonoid glycosides from a complex matrix in a single chromatographic run using U(H)PLC-ESI-IMS-HDMS/MS(E) is presented. This system operates using alternative low and high energy voltages that is able to perform the task of conventional MS/MS in a data-independent way without re-injection of the sample, which saves analytical time. Also, ion mobility separation (IMS) was employed as an additional separation technique for compounds that are co-eluting after U(H)PLC separation. First, the fragmentation of flavonoid standards were analyzed and criteria was set for structural elucidation of flavonoids in a plant extract. Based on retention times, UV spectra, exact mass, and MS fragment characteristics, such as abundances of daughter ions and the presence of radical ions ([Y0-H](-)), a total 19 flavonoid glycosides, of which 8 non-acylated and 11 acylated, were detected and structurally characterized in a cauliflower waste extract. Kaempferol and quercetin were the main aglycones detected while sinapic and ferulic acid were the main phenolic acids. C-glycosides were also found although their structure could not be elucidated. The proposed method can be used as a rapid screening test for flavonoid identification and for routine analysis of plant extracts, such as these derived from cauliflower waste. The study also confirms that agroindustrial wastes, such as cauliflower leaves, could be seen as a valuable source of different bioactive phenolic compounds. PMID:24280615

  3. Acyl-acyl carrier protein as a source of fatty acids for bacterial bioluminescence

    SciTech Connect

    Byers, D.M.; Meighen, E.A.

    1985-09-01

    Pulse-chase experiments with (/sup 3/H)tetradecanoic acid and ATP showed that the bioluminescence-related 32-kDa acyltransferase from Vibrio harveyi can specifically catalyze the deacylation of a /sup 3/H-labeled 18-kDa protein observed in extracts of this bacterium. The 18-kDa protein has been partially purified and its physical and chemical properties strongly indicate that it is fatty acyl-acyl carrier protein (acyl-ACP). Both this V. harveyi (/sup 3/H)acylprotein and (/sup 3/H)palmitoyl-ACP from Escherichia coli were substrates in vitro for either the V. harveyi 32-kDa acyltransferase or the analogous enzyme (34K) from Photobacterium phosphoreum. TLC analysis indicated that the hexane-soluble product of the reaction is fatty acid. No significant cleavage of either E. coli or V. harveyi tetradecanoyl-ACP was observed in extracts of these bacteria unless the 32-kDa or 34K acyltransferase was present. Since these enzymes are believed to be responsible for the supply of fatty acids for reduction to form the aldehyde substrate of luciferase, the above results suggest that long-chain acyl-ACP is the source of fatty acids for bioluminescence.

  4. Acylated iridoids with cytotoxicity from Valeriana jatamansi.

    PubMed

    Lin, Sheng; Shen, Yun-Heng; Li, Hui-Liang; Yang, Xian-Wen; Chen, Tao; Lu, Long-Hai; Huang, Zheng-Sheng; Liu, Run-Hui; Xu, Xi-Ke; Zhang, Wei-Dong; Wang, Hui

    2009-04-01

    Thirteen new acylated iridoids, jatamanvaltrates A-M (1-13), together with nine known valepotriates (14-22), were isolated from the whole plants of Valeriana jatamansi (syn. Valeriana wallichii). The structures of these new compounds were assigned by detailed interpretation of spectroscopic data. Jatamanvaltrates D (4) and H (9) are the first examples of naturally occurring valepotriates containing an o-hydroxybenzoyloxy moiety at C-10. All isolated compounds were tested for their cytotoxicity against lung adenocarcinoma (A549), metastatic prostate cancer (PC-3M), colon cancer (HCT-8), and hepatoma (Bel7402) cell lines.

  5. Disequilibrium of Flavonol Synthase and Dihydroflavonol-4-Reductase Expression Associated Tightly to White vs. Red Color Flower Formation in Plants

    PubMed Central

    Luo, Ping; Ning, Guogui; Wang, Zhen; Shen, Yuxiao; Jin, Huanan; Li, Penghui; Huang, Shasha; Zhao, Jian; Bao, Manzhu

    2016-01-01

    Flower color is the main character throughout the plant kingdom. Though substantial information exists regarding the structural and regulatory genes involved in anthocyanin and flavonol biosynthesis, little is known that what make a diverse white vs. red color flower in natural species. Here, the contents of pigments in seven species from varied phylogenetic location in plants with red and white flowers were determined. Flavonols could be detected in red and white flowers, but anthocyanins were almost undetectable in the white cultivar. Comparisons of expression patterns of gene related to the flavonoid biosynthesis indicated that disequilibrium expression of flavonol synthase (FLS) and dihydroflavonol-4-reductase (DFR) genes determined the accumulation of flavonols and anothcyanins in both red and white flowers of seven species. To further investigate the role of such common regulatory patterns in determining flower color, FLS genes were isolated from Rosa rugosa (RrFLS1), Prunus persica (PpFLS), and Petunia hybrida (PhFLS), and DFR genes were isolated from Rosa rugosa (RrDFR1) and Petunia hybrida (PhDFR). Heterologous expression of the FLS genes within tobacco host plants demonstrated conservation of function, with the transgenes promoting flavonol biosynthesis and inhibiting anthocyanin accumulation, so resulting in white flowers. Conversely, overexpression of DFR genes in tobacco displayed down-regulation of the endogenous NtFLS gene, and the promotion of anthocyanin synthesis. On this basis, we propose a model in which FLS and DFR gene-products compete for common substrates in order to direct the biosynthesis of flavonols and anthocyanins, respectively, thereby determining white vs. red coloration of flowers. PMID:26793227

  6. Disequilibrium of Flavonol Synthase and Dihydroflavonol-4-Reductase Expression Associated Tightly to White vs. Red Color Flower Formation in Plants.

    PubMed

    Luo, Ping; Ning, Guogui; Wang, Zhen; Shen, Yuxiao; Jin, Huanan; Li, Penghui; Huang, Shasha; Zhao, Jian; Bao, Manzhu

    2015-01-01

    Flower color is the main character throughout the plant kingdom. Though substantial information exists regarding the structural and regulatory genes involved in anthocyanin and flavonol biosynthesis, little is known that what make a diverse white vs. red color flower in natural species. Here, the contents of pigments in seven species from varied phylogenetic location in plants with red and white flowers were determined. Flavonols could be detected in red and white flowers, but anthocyanins were almost undetectable in the white cultivar. Comparisons of expression patterns of gene related to the flavonoid biosynthesis indicated that disequilibrium expression of flavonol synthase (FLS) and dihydroflavonol-4-reductase (DFR) genes determined the accumulation of flavonols and anothcyanins in both red and white flowers of seven species. To further investigate the role of such common regulatory patterns in determining flower color, FLS genes were isolated from Rosa rugosa (RrFLS1), Prunus persica (PpFLS), and Petunia hybrida (PhFLS), and DFR genes were isolated from Rosa rugosa (RrDFR1) and Petunia hybrida (PhDFR). Heterologous expression of the FLS genes within tobacco host plants demonstrated conservation of function, with the transgenes promoting flavonol biosynthesis and inhibiting anthocyanin accumulation, so resulting in white flowers. Conversely, overexpression of DFR genes in tobacco displayed down-regulation of the endogenous NtFLS gene, and the promotion of anthocyanin synthesis. On this basis, we propose a model in which FLS and DFR gene-products compete for common substrates in order to direct the biosynthesis of flavonols and anthocyanins, respectively, thereby determining white vs. red coloration of flowers. PMID:26793227

  7. 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

  8. Acyl-ACP Substrate Recognition in Burkholderia mallei BmaI1 Acyl-Homoserine Lactone Synthase

    PubMed Central

    2015-01-01

    The acyl-homoserine lactone (AHL) autoinducer mediated quorum sensing regulates virulence in several pathogenic bacteria. The hallmark of an efficient quorum sensing system relies on the tight specificity in the signal generated by each bacterium. Since AHL signal specificity is derived from the acyl-chain of the acyl-ACP (ACP = acyl carrier protein) substrate, AHL synthase enzymes must recognize and react with the native acyl-ACP with high catalytic efficiency while keeping reaction rates with non-native acyl-ACPs low. The mechanism of acyl-ACP substrate recognition in these enzymes, however, remains elusive. In this study, we investigated differences in catalytic efficiencies for shorter and longer chain acyl-ACP substrates reacting with an octanoyl-homoserine lactone synthase Burkholderia mallei BmaI1. With the exception of two-carbon shorter hexanoyl-ACP, the catalytic efficiencies of butyryl-ACP, decanoyl-ACP, and octanoyl-CoA reacting with BmaI1 decreased by greater than 20-fold compared to the native octanoyl-ACP substrate. Furthermore, we also noticed kinetic cooperativity when BmaI1 reacted with non-native acyl-donor substrates. Our kinetic data suggest that non-native acyl-ACP substrates are unable to form a stable and productive BmaI1·acyl-ACP·SAM ternary complex and are thus effectively discriminated by the enzyme. These results offer insights into the molecular basis of substrate recognition for the BmaI1 enzyme. PMID:25215658

  9. Accumulation of Flavonols over Hydroxycinnamic Acids Favors Oxidative Damage Protection under Abiotic Stress.

    PubMed

    Martinez, Vicente; Mestre, Teresa C; Rubio, Francisco; Girones-Vilaplana, Amadeo; Moreno, Diego A; Mittler, Ron; Rivero, Rosa M

    2016-01-01

    Efficient detoxification of reactive oxygen species (ROS) is thought to play a key role in enhancing the tolerance of plants to abiotic stresses. Although multiple pathways, enzymes, and antioxidants are present in plants, their exact roles during different stress responses remain unclear. Here, we report on the characterization of the different antioxidant mechanisms of tomato plants subjected to heat stress, salinity stress, or a combination of both stresses. All the treatments applied induced an increase of oxidative stress, with the salinity treatment being the most aggressive, resulting in plants with the lowest biomass, and the highest levels of H2O2 accumulation, lipid peroxidation, and protein oxidation. However, the results obtained from the transcript expression study and enzymatic activities related to the ascorbate-glutathione pathway did not fully explain the differences in the oxidative damage observed between salinity and the combination of salinity and heat. An exhaustive metabolomics study revealed the differential accumulation of phenolic compounds depending on the type of abiotic stress applied. An analysis at gene and enzyme levels of the phenylpropanoid metabolism concluded that under conditions where flavonols accumulated to a greater degree as compared to hydroxycinnamic acids, the oxidative damage was lower, highlighting the importance of flavonols as powerful antioxidants, and their role in abiotic stress tolerance.

  10. Experimental and theoretical investigation effect of flavonols antioxidants on DNA damage.

    PubMed

    Ensafi, Ali A; Heydari-Soureshjani, E; Jafari-Asl, M; Rezaei, B; Ghasemi, Jahan B; Aghaee, Elham

    2015-08-01

    A new electrochemical biosensor was developed to demonstrate the effect of Acridine Orange (AO) on DNA damage. Then, the biosensor was used to check the inhibitors effect of three flavonols antioxidants (myricetin, fisetin and kaempferol) on DNA damage. Acridine Orange (AO) was used as a damaging agent because it shows a high affinity to nucleic acid and stretch of the double helical structure of DNA. Decreasing on the oxidation signals of adenine and guanine (in the DNA) in the presence of AO were used as probes to study the antioxidants power, using DNA-modified screen printed graphene electrode (DNA/SPGE). The results of our study showed that the DNA-biosensor could be suitable biosensor to investigate the inhibitors ability of the flavonols antioxidants on the DNA damage. The linear dependency was detected in the two regions in the ranges of 1.0-15.0 and 15.0-500.0 pmol L(-1). The detection limit was found 0.5 pmol L(-1) and 0.6 pmol L(-1) for guanine and adenine, respectively. To confirm the electrochemical results, Uv-Vis and fluorescence spectroscopic methods were used too. Finally molecular dynamic (MD) simulation was performed on the structure of DNA in a water box to study any interaction between the antioxidant, AO and DNA.

  11. Accumulation of Flavonols over Hydroxycinnamic Acids Favors Oxidative Damage Protection under Abiotic Stress

    PubMed Central

    Martinez, Vicente; Mestre, Teresa C.; Rubio, Francisco; Girones-Vilaplana, Amadeo; Moreno, Diego A.; Mittler, Ron; Rivero, Rosa M.

    2016-01-01

    Efficient detoxification of reactive oxygen species (ROS) is thought to play a key role in enhancing the tolerance of plants to abiotic stresses. Although multiple pathways, enzymes, and antioxidants are present in plants, their exact roles during different stress responses remain unclear. Here, we report on the characterization of the different antioxidant mechanisms of tomato plants subjected to heat stress, salinity stress, or a combination of both stresses. All the treatments applied induced an increase of oxidative stress, with the salinity treatment being the most aggressive, resulting in plants with the lowest biomass, and the highest levels of H2O2 accumulation, lipid peroxidation, and protein oxidation. However, the results obtained from the transcript expression study and enzymatic activities related to the ascorbate-glutathione pathway did not fully explain the differences in the oxidative damage observed between salinity and the combination of salinity and heat. An exhaustive metabolomics study revealed the differential accumulation of phenolic compounds depending on the type of abiotic stress applied. An analysis at gene and enzyme levels of the phenylpropanoid metabolism concluded that under conditions where flavonols accumulated to a greater degree as compared to hydroxycinnamic acids, the oxidative damage was lower, highlighting the importance of flavonols as powerful antioxidants, and their role in abiotic stress tolerance. PMID:27379130

  12. Effect of flavonols on wine astringency and their interaction with human saliva.

    PubMed

    Ferrer-Gallego, Raúl; Brás, Natércia F; García-Estévez, Ignacio; Mateus, Nuno; Rivas-Gonzalo, Julián C; de Freitas, Victor; Escribano-Bailón, M Teresa

    2016-10-15

    The addition of external phenolic compounds to wines in order to improve their sensory quality is an established winemaking practice. This study was aimed at evaluating the effect of the addition of quercetin 3-O-glucoside on the astringency and bitterness of wines. Sensory results showed that the addition of this flavonol to wines results in an increase in astringency and bitterness. Additionally, flavonol-human salivary protein interactions were studied using fluorescence spectroscopy, dynamic light scattering and molecular dynamic simulations (MD). The apparent Stern-Volmer (KsvApp) and the apparent bimolecular quenching constants (kqApp) were calculated from fluorescence spectra. The KsvApp was 12620±390M(-1), and the apparent biomolecular constant was 3.94×10(12)M(-1)s(-1), which suggests that a complex was formed between the human salivary proteins and quercetin 3-O-glucoside. MD simulations showed that the quercetin 3-O-glucoside molecules have the ability to bind to the IB937 model peptide.

  13. Molecular imprinted polymer for solid-phase extraction of flavonol aglycones from Moringa oleifera extracts.

    PubMed

    Pakade, Vusumzi; Cukrowska, Ewa; Lindahl, Sofia; Turner, Charlotta; Chimuka, Luke

    2013-02-01

    Molecular imprinted polymer produced using quercetin as the imprinting compound was applied for the extraction of flavonol aglycones (quercetin and kaempferol) from Moringa oleifera methanolic extracts obtained using heated reflux extraction method. Identification and quantification of these flavonols in the Moringa extracts was achieved using high performance liquid chromatography with ultra violet detection. Breakthrough volume and retention capacity of molecular imprinted polymer SPE was investigated using a mixture of myricetin, quercetin and kaempferol. The calculated theoretical number of plates was found to be 14, 50 and 8 for myricetin, quercetin and kaempferol, respectively. Calculated adsorption capacities were 2.0, 3.4 and 3.7 μmol/g for myricetin, quercetin and kaempferol, respectively. No myricetin was observed in Moringa methanol extracts. Recoveries of quercetin and kaempferol from Moringa methanol extracts of leaves and flowers ranged from 77 to 85% and 75 to 86%, respectively, demonstrating the feasibility of using the developed molecularly imprinted SPE method for quantitative clean-up of both of these flavonoids. Using heated reflux extraction combined with molecularly imprinted SPE, quercetin concentrations of 975 ± 58 and 845 ± 32 mg/kg were determined in Moringa leaves and flowers, respectively. However, the concentrations of kaempferol found in leaves and flowers were 2100 ± 176 and 2802 ± 157 mg/kg, respectively.

  14. Accumulation of Flavonols over Hydroxycinnamic Acids Favors Oxidative Damage Protection under Abiotic Stress.

    PubMed

    Martinez, Vicente; Mestre, Teresa C; Rubio, Francisco; Girones-Vilaplana, Amadeo; Moreno, Diego A; Mittler, Ron; Rivero, Rosa M

    2016-01-01

    Efficient detoxification of reactive oxygen species (ROS) is thought to play a key role in enhancing the tolerance of plants to abiotic stresses. Although multiple pathways, enzymes, and antioxidants are present in plants, their exact roles during different stress responses remain unclear. Here, we report on the characterization of the different antioxidant mechanisms of tomato plants subjected to heat stress, salinity stress, or a combination of both stresses. All the treatments applied induced an increase of oxidative stress, with the salinity treatment being the most aggressive, resulting in plants with the lowest biomass, and the highest levels of H2O2 accumulation, lipid peroxidation, and protein oxidation. However, the results obtained from the transcript expression study and enzymatic activities related to the ascorbate-glutathione pathway did not fully explain the differences in the oxidative damage observed between salinity and the combination of salinity and heat. An exhaustive metabolomics study revealed the differential accumulation of phenolic compounds depending on the type of abiotic stress applied. An analysis at gene and enzyme levels of the phenylpropanoid metabolism concluded that under conditions where flavonols accumulated to a greater degree as compared to hydroxycinnamic acids, the oxidative damage was lower, highlighting the importance of flavonols as powerful antioxidants, and their role in abiotic stress tolerance. PMID:27379130

  15. Emulsifying properties of acylated rapeseed (Brassica napus L.) peptides.

    PubMed

    Sánchez-Vioque, Raúl; Bagger, Christian L; Larré, Colette; Guéguen, Jacques

    2004-03-01

    A peptide fraction having an average size of 5.6 amino acids has been purified from a rapeseed hydrolyzate, acylated using C(10)-C(14) acyl chlorides, and the surface tension values at the air-water interface and emulsifying properties studied. As compared with standard surface-active proteins, such as bovine serum albumin (BSA), and with detergents such as sodium dodecyl sulfate (SDS), acylated peptides exhibited particular surface characteristics. The surface tension at air-water interface of acylated peptides ranged from 29.1 to 37.8 mN/m at equilibrium; these values were considerably lower than those for BSA and closer those for SDS, suggesting that acylated peptides pack at the air-water interface more like detergents than like proteins. The adsorption of acylated peptides to the oil-water interface was slower than for SDS or BSA, as deduced from the rather large size of oil droplets in emulsions (31-17 microm). Consequently, these emulsions creamed extensively during aging. Nevertheless, emulsions generated from acylated peptides were in general more stable to phase separation than those prepared from SDS. The C(14) acylated peptides were more effective for generating emulsions than the C(10) and C(12) derivatives, especially concerning the stability of emulsions against coalescence and phase separation, which was better than SDS and close to BSA.

  16. Understanding Acyl Chain and Glycerolipid Metabolism in Plants

    SciTech Connect

    Ohlrogge, John B.

    2013-11-05

    Progress is reported in these areas: acyl-editing in initial eukaryotic lipid assembly in soybean seeds; identification and characterization of two Arabidopsis thaliana lysophosphatidyl acyltransferases with preference for lysophosphatidylethanolamine; and characterization and subcellular distribution of lysolipid acyl transferase activity of pea leaves.

  17. Characterization of the "Escherichia Coli" Acyl Carrier Protein Phosphodiesterase

    ERIC Educational Resources Information Center

    Thomas, Jacob

    2009-01-01

    Acyl carrier protein (ACP) is a small essential protein that functions as a carrier of the acyl intermediates of fatty acid synthesis. ACP requires the posttranslational attachment of a 4'phosphopantetheine functional group, derived from CoA, in order to perform its metabolic function. A Mn[superscript 2+] dependent enzymatic activity that removes…

  18. Are There Acyl-Homoserine Lactones within Mammalian Intestines?

    PubMed Central

    Swearingen, Matthew C.; Sabag-Daigle, Anice

    2013-01-01

    Many Proteobacteria are capable of quorum sensing using N-acyl-homoserine lactone (acyl-HSL) signaling molecules that are synthesized by LuxI or LuxM homologs and detected by transcription factors of the LuxR family. Most quorum-sensing species have at least one LuxR and one LuxI homolog. However, members of the Escherichia, Salmonella, Klebsiella, and Enterobacter genera possess only a single LuxR homolog, SdiA, and no acyl-HSL synthase. The most obvious hypothesis is that these organisms are eavesdropping on acyl-HSL production within the complex microbial communities of the mammalian intestinal tract. However, there is currently no evidence of acyl-HSLs being produced within normal intestinal communities. A few intestinal pathogens, including Yersinia enterocolitica, do produce acyl-HSLs, and Salmonella can detect them during infection. Therefore, a more refined hypothesis is that SdiA orthologs are used for eavesdropping on other quorum-sensing pathogens in the host. However, the lack of acyl-HSL signaling among the normal intestinal residents is a surprising finding given the complexity of intestinal communities. In this review, we examine the evidence for and against the possibility of acyl-HSL signaling molecules in the mammalian intestine and discuss the possibility that related signaling molecules might be present and awaiting discovery. PMID:23144246

  19. Effects of tripterygium glycosides on restenosis following endovascular treatment

    PubMed Central

    HAN, BING; GE, CHANG-QING; ZHANG, HONG-GUANG; ZHOU, CHEN-GUANG; JI, GUO-HUI; YANG, ZHENG; ZHANG, LIANG

    2016-01-01

    The mechanism and associated factors of restenosis following intravascular stent implantation remain to be elucidated. The present two-part experimental and clinical study aimed to investigate the effects of tripterygium glycosides on in-stent restenosis subsequent to intra-arterial therapy. Following endovascular stent implantation in rabbit iliac arteries, post-stent outcomes were evaluated in cyclosporine groups, low-dose and high-dose tripterygium glycosides groups and controls. Post-operative angiography indicated that vessel diameters were similar between groups; however, at 28 days after receiving the therapeutic agents, vessels of the cyclosporine and tripterygium glycosides groups were significantly larger than those of the controls. Furthermore, three groups of patients had comparable baseline levels of interleukin (IL)-10, IL-18 and C-reactive protein, and intima-media thickness. However, 1 month after stent implantation, levels of IL-10 and IL-18 were markedly reduced in the high- and low-dose tripterygium glycosides groups compared with controls. At 6 months after surgery, the stent patency rate in patients with bare stents was significantly lower than in patients receiving tripterygium glycosides (P≤0.009). In addition, the ankle-brachial index was also higher than in those without tripterygium glycosides (P<0.001). Results of the experimental and clinical studies suggest that tripterygium glycosides may inhibit and possibly aid in the prevention of in-stent restenosis formation following endovascular treatment of lower-extremity artery disease. PMID:27108914

  20. Determination of phenylethanoid glycosides and iridoid glycosides from therapeutically used Plantago species by CE-MEKC.

    PubMed

    Gonda, Sándor; Nguyen, Nhat Minh; Batta, Gyula; Gyémánt, Gyöngyi; Máthé, Csaba; Vasas, Gábor

    2013-09-01

    CE methods are valuable tools for medicinal plant quality management, screening, and analysis. Therefore, the aim of the current study was to optimize and validate a CE-MEKC method for simultaneous quantification of four chief bioactive metabolites from Plantago species. The two most important secondary metabolite groups were aimed to be separated. Different electrolyte and surfactant types were tested. Surfactant concentration, BGE pH, electrolyte concentration, and buffering capacity were optimized. The final BGE consisted of 15 mM sodium tetraborate, 20 mM TAPS, and 250 mM DOC at pH 8.50. Acceptable precision, good stability, and accuracy were achieved, with high resolution for phenylethanoid glycosides. Analytes were separated within 20 min. The method was shown to be suitable for the quantification of the iridoid glycosides aucubin and catalpol, and the phenylethanoid glycosides acteoside (verbascoside) and plantamajoside from water extracts of different samples. The method was shown to be applicable to leaf extracts of Plantago lanceolata, Plantago major, and Plantago asiatica, the main species with therapeutic applications, and a biotechnological product, plant tissue cultures (calli) of P. lanceolata. Baseline separation of the main constituents from minor peaks was achieved, regardless of the matrix type.

  1. Determination of phenylethanoid glycosides and iridoid glycosides from therapeutically used Plantago species by CE-MEKC.

    PubMed

    Gonda, Sándor; Nguyen, Nhat Minh; Batta, Gyula; Gyémánt, Gyöngyi; Máthé, Csaba; Vasas, Gábor

    2013-09-01

    CE methods are valuable tools for medicinal plant quality management, screening, and analysis. Therefore, the aim of the current study was to optimize and validate a CE-MEKC method for simultaneous quantification of four chief bioactive metabolites from Plantago species. The two most important secondary metabolite groups were aimed to be separated. Different electrolyte and surfactant types were tested. Surfactant concentration, BGE pH, electrolyte concentration, and buffering capacity were optimized. The final BGE consisted of 15 mM sodium tetraborate, 20 mM TAPS, and 250 mM DOC at pH 8.50. Acceptable precision, good stability, and accuracy were achieved, with high resolution for phenylethanoid glycosides. Analytes were separated within 20 min. The method was shown to be suitable for the quantification of the iridoid glycosides aucubin and catalpol, and the phenylethanoid glycosides acteoside (verbascoside) and plantamajoside from water extracts of different samples. The method was shown to be applicable to leaf extracts of Plantago lanceolata, Plantago major, and Plantago asiatica, the main species with therapeutic applications, and a biotechnological product, plant tissue cultures (calli) of P. lanceolata. Baseline separation of the main constituents from minor peaks was achieved, regardless of the matrix type. PMID:23784714

  2. Steviol glycoside safety: are highly purified steviol glycoside sweeteners food allergens?

    PubMed

    Urban, Jonathan D; Carakostas, Michael C; Taylor, Steve L

    2015-01-01

    Steviol glycoside sweeteners are extracted from the plant Stevia rebaudiana (Bertoni), a member of the Asteraceae (Compositae) family. Many plants from this family can induce hypersensitivity reactions via multiple routes of exposure (e.g., ragweed, goldenrod, chrysanthemum, echinacea, chamomile, lettuce, sunflower and chicory). Based on this common taxonomy, some popular media reports and resources have issued food warnings alleging the potential for stevia allergy. To determine if such allergy warnings are warranted on stevia-based sweeteners, a comprehensive literature search was conducted to identify all available data related to allergic responses following the consumption of stevia extracts or highly purified steviol glycosides. Hypersensitivity reactions to stevia in any form are rare. The few cases documented in the peer-reviewed literature were reported prior to the introduction of high-purity products to the market in 2008 when many global regulatory authorities began to affirm the safety of steviol glycosides. Neither stevia manufacturers nor food allergy networks have reported significant numbers of any adverse events related to ingestion of stevia-based sweeteners, and there have been no reports of stevia-related allergy in the literature since 2008. Therefore, there is little substantiated scientific evidence to support warning statements to consumers about allergy to highly purified stevia extracts. PMID:25449199

  3. New steroidal glycosides from Tribulus terrestris L.

    PubMed

    Chen, Gang; Liu, Tao; Lu, Xuan; Wang, Hai-Feng; Hua, Hui-Ming; Pei, Yue-Hu

    2012-01-01

    Two new steroidal glycosides were isolated from Tribulus terrestris L. Their structures were elucidated as 26-O-β-D-glucopyranosyl-5α-furostan-12-one-20(22)-ene-3β,23,26-triol-3-O-β-D-xylopyranosyl-(1 → 2)-[β-D-xylopyranosyl-(1 → 3)]-β-D-glucopyranosyl-(1 → 4)-[α-L-rhamnopyranosyl-(1 → 2)]-β-D-galactopyranoside (1) and 26-O-β-D-glucopyranosyl-5α-furostan-20(22)-ene-3β,23,26-triol-3-O-β-D-xylopyranosyl-(1 → 2)-[β-D-xylopyranosyl-(1 → 3)]-β-D-glucopyranosyl-(1 → 4)-[α-L-rhamnopyranosyl-(1 → 2)]-β-D-galactopyranoside (2) by spectroscopic methods including 1D and 2D NMR experiments.

  4. A new phenolic glycoside from Juglans mandshurica.

    PubMed

    Yao, Dalei; Jin, Mei; Zhang, Changhao; Luo, Jie; Li, Ren; Zheng, Mingshan; Cui, Jiongmo; Li, Gao

    2014-01-01

    A new phenolic glycoside, 6-O-(4'-hydroxy-3',5'-dimethoxybenzoyl)-d-glucopyranose (4), and nine known compounds (1-3 and 5-10) were isolated from Juglans mandshurica Maxim. Compound structures were elucidated by NMR, HR-ESI-MS and acid hydrolysis. Compounds 5 and 6 are reported from this genus for the first time. Among compounds 1-10, only 1 exhibited cytotoxicity against MGC-803, A549, K562, JAR, HeLa, CaSKi and SiHa cell lines (IC50: 2.0, 5.3, 2.3, 6.9, 4.0, 6.6 and 2.7 μM, respectively).

  5. Lysine fatty acylation promotes lysosomal targeting of TNF-α

    PubMed Central

    Jiang, Hong; Zhang, Xiaoyu; Lin, Hening

    2016-01-01

    Tumor necrosis factor-α (TNF-α) is a proinflammation cytokine secreted by various cells. Understanding its secretive pathway is important to understand the biological functions of TNF-α and diseases associated with TNF-α. TNF-α is one of the first proteins known be modified by lysine fatty acylation (e.g. myristoylation). We previously demonstrated that SIRT6, a member of the mammalian sirtuin family of enzymes, can remove the fatty acyl modification on TNF-α and promote its secretion. However, the mechanistic details about how lysine fatty acylation regulates TNF-α secretion have been unknown. Here we present experimental data supporting that lysine fatty acylation promotes lysosomal targeting of TNF-α. The result is an important first step toward understanding the biological functions of lysine fatty acylation. PMID:27079798

  6. Acyl peptidic siderophores: structures, biosyntheses and post-assembly modifications.

    PubMed

    Kem, Michelle P; Butler, Alison

    2015-06-01

    Acyl peptidic siderophores are produced by a variety of bacteria and possess unique amphiphilic properties. Amphiphilic siderophores are generally produced in a suite where the iron(III)-binding headgroup remains constant while the fatty acid appendage varies by length and functionality. Acyl peptidic siderophores are commonly synthesized by non-ribosomal peptide synthetases; however, the method of peptide acylation during biosynthesis can vary between siderophores. Following biosynthesis, acyl siderophores can be further modified enzymatically to produce a more hydrophilic compound, which retains its ferric chelating abilities as demonstrated by pyoverdine from Pseudomonas aeruginosa and the marinobactins from certain Marinobacter species. Siderophore hydrophobicity can also be altered through photolysis of the ferric complex of certain β-hydroxyaspartic acid-containing acyl peptidic siderophores. PMID:25677460

  7. Spectroscopic manifestation of stretching vibrations of glycosidic linkage in polysaccharides

    NASA Astrophysics Data System (ADS)

    Nikonenko, N. A.; Buslov, D. K.; Sushko, N. I.; Zhbankov, R. G.

    2005-10-01

    Manifestation of stretching vibrations of glycosidic linkage in the infrared spectra of polysaccharides (native, microcrystalline, mercerized celluloses, amylose, starches) has been studied using the regularized method of deconvolution. It has been shown that the glycosidic linkage formation in the polysaccharides is characterized by the appearance of new absorption bands in the 1175-1140 cm -1 range as compared to their corresponding monomers. In the 1000-920 cm -1 region differences between the infrared spectra of polysaccharides due to the changes in the glycosidic linkage configuration have been found.

  8. K2CO3-promoted formation of aryl esters from primary aryl amides by the acyl-acyl exchange process.

    PubMed

    Bian, Yongjun; Qu, Xingyu

    2016-04-28

    A new acyl-acyl exchange reaction has been developed for the formation of aryl esters from primary aryl amides. The reaction could occur under mild reaction conditions with catalytic quantities of K2CO3, and could afford moderate to good yields of the desired products. PMID:27035611

  9. Friedel-Craft acylation of ar-himachalene: synthesis of acyl-ar-himachalene and a new acyl-hydroperoxide.

    PubMed

    Hossini, Issam; Harrad, Mohamed Anoir; Ait Ali, Mustapha; El Firdoussi, Larbi; Karim, Abdallah; Valerga, Pedro; Puerta, M Carmen

    2011-01-01

    Friedel-Craft acylation at 100 °C of 2,5,9,9-tetramethyl-6,7,8,9-tetrahydro-5H-benzocycloheptene [ar-himachalene], a sesquiterpenic hydrocarbon obtained by catalytic dehydrogenation of α-, β- and γ-himachalenes, produces a mixture of two compounds: (3,5,5,9-tetramethyl-6,7,8,9-tetrahydro-5H-benzocyclohepten-2-yl)-ethanone (2, in 69% yield), with a conserved reactant backbone, and 3, with a different skeleton, in 21% yield. The crystal structure of 3 reveals it to be 1-(8-ethyl-8-hydroperoxy-3,5,5-trimethyl-5,6,7,8-tetrahydronaphthalen-2-yl)-ethanone. In this compound O-H…O bonds form dimers. These hydrogen-bonds, in conjunction with weaker C-H…O interactions, form a more extended supramolecular arrangement in the crystal. PMID:21760570

  10. Calyx diversity of flavonols and fatty acids in Roselle (Hibiscus sabdariffa) for use as a potential nutraceutical crop.

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Flavonols and fatty acids in plants has potential to be used as an antioxidant, lowering of cholesterol, and for cancer prevention. Roselle is a photoperiod and frost-sensitive species requiring greenhouse production in the Griffin, GA environment. Six accessions of roselle calyces were evaluated fo...

  11. Resin glycosides from the aerial parts of Operculina turpethum.

    PubMed

    Ding, Wenbing; Jiang, Zi-Hua; Wu, Ping; Xu, Liangxiong; Wei, Xiaoyi

    2012-09-01

    Three glycosidic acids, turpethic acids A-C, and two intact resin glycosides, turpethosides A and B, all having a common pentasaccharide moiety and 12-hydroxy fatty acid aglycones of different chain lengths, were obtained from the aerial parts of Operculina turpethum. Their structures were elucidated by spectroscopic analyses and chemical correlations. The aglycones were characterized as 12-hydroxypentadecanoic acid in two compounds, 12-hydroxyhexadecanoic acid in two other components, and 12-hydroxyheptadecanoic acid in the fifth compound, which were all confirmed by synthesis. The absolute configurations of these aglycones were all established as S by Mosher's method. These compounds represent the first examples of resin glycosides with a monohydroxylated 12-hydroxy fatty acid as an aglycone, and one compound is the first described resin glycoside having a hydroxylated C(17) fatty acid as its aglycone.

  12. Acyl-acyl carrier protein thioesterase activity from sunflower (Helianthus annuus L.) seeds.

    PubMed

    Martínez-Force, E; Cantisán, S; Serrano-Vega, M J; Garcés, R

    2000-10-01

    During sunflower (Helianthus annuus L.) seed formation there was an active period of lipid biosynthesis between 12 and 28 days after flowering (DAF). The maximum in-vitro acyl-acyl carrier protein (ACP) thioesterase activities (EC 3.1.2.14) were found at 15 DAF, preceding the largest accumulation of lipid in the seed. Data from the apparent kinetic parameters, Vmax and Km, from seeds of 15 and 30 DAF, showed that changes in acyl-ACP thioesterase activity are not only quantitative, but also qualitative, since, although the preferred substrate was always oleoyl-ACP, the affinity for palmitoyl-ACP decreased, whereas that for stearoyl-ACP increased with seed maturation. Bisubstrate assays carried out at 30 DAF seemed to indicate that the total activity found in mature seeds is due to a single enzyme with 100/75/15 affinity for oleoyl-ACP/stearoyl-ACP/ palmitoyl-ACP. In contrast, at 15 DAF, enzymatic data together with partial sequences from cDNAs indicated the presence of at least two enzymes with different properties, a FatA-like thioesterase, with a high affinity for oleoyl-ACP, plus a FatB-like enzyme, with preference for long-chain saturated fatty acids, both being expressed during the active lipid biosynthesis period. Competition assays carried out with CAS-5, a mutant with a higher content of palmitic acid in the seed oil, indicated that a modified FatA-type thioesterase is involved in the mutant phenotype.

  13. Palladium-Catalyzed Environmentally Benign Acylation.

    PubMed

    Suchand, Basuli; Satyanarayana, Gedu

    2016-08-01

    Recent trends in research have gained an orientation toward developing efficient strategies using innocuous reagents. The earlier reported transition-metal-catalyzed carbonylations involved either toxic carbon monoxide (CO) gas as carbonylating agent or functional-group-assisted ortho sp(2) C-H activation (i.e., ortho acylation) or carbonylation by activation of the carbonyl group (i.e., via the formation of enamines). Contradicting these methods, here we describe an environmentally benign process, [Pd]-catalyzed direct carbonylation starting from simple and commercially available iodo arenes and aldehydes, for the synthesis of a wide variety of ketones. Moreover, this method comprises direct coupling of iodoarenes with aldehydes without activation of the carbonyl and also without directing group assistance. Significantly, the strategy was successfully applied to the synthesis n-butylphthalide and pitofenone. PMID:27377566

  14. Two new glycosides from the florets of Carthamus tinctorius.

    PubMed

    Jiang, Jian-Shuang; Chen, Zhong; Yang, Ya-Nan; Feng, Zi-Ming; Zhang, Pei-Cheng

    2013-01-01

    Two new glycoside compounds, named saffloquinoside C (1) and (-)-4-hydroxybenzoic acid-4-O-[6'-O-(2″-methylbutyryl)-β-D-glucopyranoside] (2), were isolated from the florets of Carthamus tinctorius. Their structures were elucidated by detailed spectroscopic means including UV, IR, HR-ESI-MS, 1D and 2D NMR, and CD data. Compound 1 was a rare quinochalcone glycoside with six five-membered dioxaspirocycle.

  15. Phenolic glycosides from sugar maple (Acer saccharum) bark.

    PubMed

    Yuan, Tao; Wan, Chunpeng; González-Sarrías, Antonio; Kandhi, Vamsikrishna; Cech, Nadja B; Seeram, Navindra P

    2011-11-28

    Four new phenolic glycosides, saccharumosides A-D (1-4), along with eight known phenolic glycosides, were isolated from the bark of sugar maple (Acer saccharum). The structures of 1-4 were elucidated on the basis of spectroscopic data analysis. All compounds isolated were evaluated for cytotoxicity effects against human colon tumorigenic (HCT-116 and Caco-2) and nontumorigenic (CCD-18Co) cell lines. PMID:22032697

  16. Phenolic glycosides from sugar maple (Acer saccharum) bark.

    PubMed

    Yuan, Tao; Wan, Chunpeng; González-Sarrías, Antonio; Kandhi, Vamsikrishna; Cech, Nadja B; Seeram, Navindra P

    2011-11-28

    Four new phenolic glycosides, saccharumosides A-D (1-4), along with eight known phenolic glycosides, were isolated from the bark of sugar maple (Acer saccharum). The structures of 1-4 were elucidated on the basis of spectroscopic data analysis. All compounds isolated were evaluated for cytotoxicity effects against human colon tumorigenic (HCT-116 and Caco-2) and nontumorigenic (CCD-18Co) cell lines.

  17. 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

  18. Stability of steviol glycosides in several food matrices.

    PubMed

    Jooken, Etienne; Amery, Ruis; Struyf, Tom; Duquenne, Barbara; Geuns, Jan; Meesschaert, Boudewijn

    2012-10-24

    As steviol glycosides are now allowed as a food additive in the European market, it is important to assess the stability of these steviol glycosides after they have been added to different food matrices. We analyzed and tested the stability of steviol glycosides in semiskimmed milk, soy drink, fermented milk drink, ice cream, full-fat and skimmed set yogurt, dry biscuits, and jam. The fat was removed by centrifugation from the dairy and soy drink samples. Proteins were precipitated by the addition of acetonitrile and also removed by centrifugation. Samples of jam were extracted with water. Dry biscuits were extracted with ethanol. The resulting samples were concentrated with solid-phase extraction and analyzed by high-performance liquid chromatography on a C18 stationary phase and a gradient of acetonitrile/aqueous 25 mM phosphoric acid. The accuracy was checked using a standard addition on some samples. For assessing the stability of the steviol glycosides, samples were stored in conditions relevant to each food matrix and analyzed periodically. The results indicate that steviol glycosides can be analyzed with good precision and accuracy in these food categories. The recovery was between 96 and 103%. The method was also validated by standard addition, which showed excellent agreement with the external calibration curve. No sign of decomposition of steviol glycosides was found in any of the samples.

  19. Decomposition of α-Tocopheryl Glycosides in Rat Tissues

    PubMed Central

    Knaś, Małgorzata; Wałejko, Piotr; Maj, Jadwiga; Hryniewicka, Agnieszka; Witkowski, Stanisław; Borzym-Kluczyk, Małgorzata; Dudzik, Danuta; Zwierz, Krzysztof

    2008-01-01

    Background The aim of our investigation was to estimate the stability of α-tocopheryl O-glycosides in relation to activity of exoglycosidases in selected rat tissues. Material and Methods Acetylated glycosides were obtained in glucosidation of α-tocopherol using the Helferich method. The activity of exoglycosidases was determined by the Zwierz et al. method. Protein concentrations were determined by the biuret method. The concentration of released α-tocopherol was determined with the HPLC method. Results The comparison of the amount of released α-tocopherol with the amount of released p-nitrophenol shows that glycoside bound in 2a–5a derivatives of α-tocopherol undergoes hydrolysis significantly harder than in appropriate 2b–5b p-nitrophenyl derivatives. Conclusion The results indicate that tocopheryl O-glycosides are more resistant to enzymatic hydrolysis than appropriate p-nitrophenol O-glycosides 2a–5a. Among examined tocopheryl O-glycosides, galactoside 4 is the only compound that caused the significant increase in tocopherol concentration, as compared to its endogenic content. PMID:19696909

  20. Role of acyl carrier protein isoforms in plant lipid metabolism

    SciTech Connect

    Not Available

    1990-01-01

    Although acyl carrier protein (ACP) is the best studied protein in plant fatty acid biosynthesis, the in vivo forms of ACPs and their steady state pools have not been examined previously in either seed or leaf. Information about the relative pool sizes of free ACP and its acyl-ACP intermediates is essential for understanding regulation of de novo fatty acid biosynthesis in plants. In this study we utilized antibodies directed against spinach ACP as a sensitive assay to analyze the acyl groups while they were still covalently attached to ACPs. 4 refs., 4 figs.

  1. A flavonol triglycoside and investigation of the antioxidant and cell stimulating activities of Annona muricata Linn.

    PubMed

    Nawwar, Mahmoud; Ayoub, Nahla; Hussein, Sahar; Hashim, Amani; El-Sharawy, Reham; Wende, Kristian; Harms, Manuela; Lindequist, Ulrike

    2012-05-01

    Chemical investigation on leaves of Annona muricata resulted in the isolation of the flavonol triglycoside, quercetin 3-O-α-rhamnosyl-(1″″ → 6″)-β-sophoroside, together with twelve known phenolics. The structures of these compounds were established by 1D- and 2D-nuclear magnetic resonance spectroscopic techniques and mass spectrometry data. The in vitro antioxidant studies of the investigated aqueous ethanol extract and its column fractions were accomplished using the oxygen radical absorbance capacity (ORAC) method. A stimulating effect on HaCaT human keratinocytes by the leaf extract was also assessed. Il-6 production after UV irradiation was not influenced by A. muricata leaf extract.

  2. Extraction and quantification of phenolic acids and flavonols from Eugenia pyriformis using different solvents.

    PubMed

    Haminiuk, Charles Windson Isidoro; Plata-Oviedo, Manuel Salvador Vicente; de Mattos, Gisely; Carpes, Solange Teresinha; Branco, Ivanise Guilherme

    2014-10-01

    The recovery of phenolic compounds of Eugenia pyriformis using different solvents was investigated in this study. The compounds were identified and quantified by reverse-phase high-performance liquid chromatography coupled with ultraviolet-visible diode-array detector (RP-HPLC-DAD/UV-vis). Absolute methanol was the most effective extraction agent of phenolic acids and flavonols (588.31 mg/Kg) from Eugenia pyriformis, although similar results (p ≤ 0.05) were observed using methanol/water (1:1 ratio). Our results clearly showed that higher contents of phenolic compounds were not obtained either with the most or the least polar solvents used. Several phenolic compounds were identified in the samples whereas gallic acid and quercetin were the major compounds recovered. PMID:25328239

  3. Fluorescence studies of interaction between flavonol p-coumaroylglucoside tiliroside and bovine serum albumin.

    PubMed

    Hu, Xiaoli; Cui, Shuya; Liu, Jia qin

    2010-10-01

    In this paper, the interaction between flavonol p-coumaroylglucoside tiliroside and BSA was investigated by fluorescence quenching spectra, synchronous fluorescence spectra, and three-dimensional fluorescence spectra under simulative physiological conditions. It was proved that the fluorescence quenching of BSA by tiliroside was mainly a result of the formation of a tiliroside-BSA complex. The modified Stern-Volmer quenching constant and the corresponding thermodynamic parameters DeltaH, DeltaG and DeltaS at different temperatures were calculated. The results indicated that electrostatic interactions were the predominant intermolecular forces in stabilizing the complex. The distance r=3.95 nm between the donor (BSA) and acceptor (tiliroside) was obtained according to Förster's nonradioactive energy transfer theory. The synchronous fluorescence and three-dimensional fluorescence spectra results showed the microenvironment and conformation of BSA were changed in the binding reaction.

  4. Fluorescence studies of interaction between flavonol p-coumaroylglucoside tiliroside and bovine serum albumin

    NASA Astrophysics Data System (ADS)

    Hu, Xiaoli; Cui, Shuya; Liu, Jia qin

    2010-10-01

    In this paper, the interaction between flavonol p-coumaroylglucoside tiliroside and BSA was investigated by fluorescence quenching spectra, synchronous fluorescence spectra, and three-dimensional fluorescence spectra under simulative physiological conditions. It was proved that the fluorescence quenching of BSA by tiliroside was mainly a result of the formation of a tiliroside-BSA complex. The modified Stern-Volmer quenching constant and the corresponding thermodynamic parameters Δ H, Δ G and Δ S at different temperatures were calculated. The results indicated that electrostatic interactions were the predominant intermolecular forces in stabilizing the complex. The distance r = 3.95 nm between the donor (BSA) and acceptor (tiliroside) was obtained according to Förster's nonradioactive energy transfer theory. The synchronous fluorescence and three-dimensional fluorescence spectra results showed the microenvironment and conformation of BSA were changed in the binding reaction.

  5. Characterization of Arabidopsis thaliana FLAVONOL SYNTHASE 1 (FLS1) -overexpression plants in response to abiotic stress.

    PubMed

    Nguyen, Nguyen Hoai; Kim, Jun Hyeok; Kwon, Jaeyoung; Jeong, Chan Young; Lee, Wonje; Lee, Dongho; Hong, Suk-Whan; Lee, Hojoung

    2016-06-01

    Flavonoids are an important group of secondary metabolites that are involved in plant growth and contribute to human health. Many studies have focused on the biosynthesis pathway, biochemical characters, and biological functions of flavonoids. In this report, we showed that overexpression of FLS1 (FLS1-OX) not only altered seed coat color (resulting in a light brown color), but also affected flavonoid accumulation. Whereas fls1-3 mutants accumulated higher anthocyanin levels, FLS1-OX seedlings had lower levels than those of the wild-type. Besides, shoot tissues of FLS1-OX plants exhibited lower flavonol levels than those of the wild-type. However, growth performance and abiotic stress tolerance of FLS1-OX, fls1-3, and wild-type plants were not significantly different. Taken together, FLS1 can be manipulated (i.e., silenced or overexpressed) to redirect the flavonoid biosynthetic pathway toward anthocyanin production without negative effects on plant growth and development.

  6. The effect of the flavonol morin on adhesion and aggregation of Streptococcus pyogenes.

    PubMed

    Green, Angharad E; Rowlands, Richard S; Cooper, Rose A; Maddocks, Sarah E

    2012-08-01

    The effect of the flavonol morin on Streptococcus pyogenes biofilm growth was determined using a static biofilm model, in which reduced biofilm biomass was observed in the presence of morin, suggesting that morin inhibited biofilm development. Morin at concentrations exceeding 225 μM had the greatest impact on biofilm biomass causing reductions of up to 65%, which was found to be statistically significant. Morin was also shown to induce rapid bacterial aggregation. Approximately 55% of S. pyogenes in liquid suspension aggregated when incubated with morin at concentrations of 275 and 300 μM for 120 min, compared to the control group in which only 10% of the cells aggregated, this was also shown to be statistically significant.

  7. Advanced Knowledge of Three Important Classes of Grape Phenolics: Anthocyanins, Stilbenes and Flavonols

    PubMed Central

    Flamini, Riccardo; Mattivi, Fulvio; De Rosso, Mirko; Arapitsas, Panagiotis; Bavaresco, Luigi

    2013-01-01

    Grape is qualitatively and quantitatively very rich in polyphenols. In particular, anthocyanins, flavonols and stilbene derivatives play very important roles in plant metabolism, thanks to their peculiar characteristics. Anthocyanins are responsible for the color of red grapes and wines and confer organoleptic characteristics on the wine. They are used for chemotaxonomic studies and to evaluate the polyphenolic ripening stage of grape. They are natural colorants, have antioxidant, antimicrobial and anticarcinogenic activity, exert protective effects on the human cardiovascular system, and are used in the food and pharmaceutical industries. Stilbenes are vine phytoalexins present in grape berries and associated with the beneficial effects of drinking wine. The principal stilbene, resveratrol, is characterized by anticancer, antioxidant, anti-inflammatory and cardioprotective activity. Resveratrol dimers and oligomers also occur in grape, and are synthetized by the vine as active defenses against exogenous attack, or produced by extracellular enzymes released from pathogens in an attempt to eliminate undesirable toxic compounds. Flavonols are a ubiquitous class of flavonoids with photo-protection and copigmentation (together with anthocyanins) functions. The lack of expression of the enzyme flavonoid 3′,5′-hydroxylase in white grapes restricts the presence of these compounds to quercetin, kaempferol and isorhamnetin derivatives, whereas red grapes usually also contain myricetin, laricitrin and syringetin derivatives. In the last ten years, the technological development of analytical instrumentation, particularly mass spectrometry, has led to great improvements and further knowledge of the chemistry of these compounds. In this review, the biosynthesis and biological role of these grape polyphenols are briefly introduced, together with the latest knowledge of their chemistry. PMID:24084717

  8. Advanced knowledge of three important classes of grape phenolics: anthocyanins, stilbenes and flavonols.

    PubMed

    Flamini, Riccardo; Mattivi, Fulvio; De Rosso, Mirko; Arapitsas, Panagiotis; Bavaresco, Luigi

    2013-01-01

    Grape is qualitatively and quantitatively very rich in polyphenols. In particular, anthocyanins, flavonols and stilbene derivatives play very important roles in plant metabolism, thanks to their peculiar characteristics. Anthocyanins are responsible for the color of red grapes and wines and confer organoleptic characteristics on the wine. They are used for chemotaxonomic studies and to evaluate the polyphenolic ripening stage of grape. They are natural colorants, have antioxidant, antimicrobial and anticarcinogenic activity, exert protective effects on the human cardiovascular system, and are used in the food and pharmaceutical industries. Stilbenes are vine phytoalexins present in grape berries and associated with the beneficial effects of drinking wine. The principal stilbene, resveratrol, is characterized by anticancer, antioxidant, anti-inflammatory and cardioprotective activity. Resveratrol dimers and oligomers also occur in grape, and are synthetized by the vine as active defenses against exogenous attack, or produced by extracellular enzymes released from pathogens in an attempt to eliminate undesirable toxic compounds. Flavonols are a ubiquitous class of flavonoids with photo-protection and copigmentation (together with anthocyanins) functions. The lack of expression of the enzyme flavonoid 3',5'-hydroxylase in white grapes restricts the presence of these compounds to quercetin, kaempferol and isorhamnetin derivatives, whereas red grapes usually also contain myricetin, laricitrin and syringetin derivatives. In the last ten years, the technological development of analytical instrumentation, particularly mass spectrometry, has led to great improvements and further knowledge of the chemistry of these compounds. In this review, the biosynthesis and biological role of these grape polyphenols are briefly introduced, together with the latest knowledge of their chemistry. PMID:24084717

  9. Competition between anthocyanin and flavonol biosynthesis produces spatial pattern variation of floral pigments between Mimulus species.

    PubMed

    Yuan, Yao-Wu; Rebocho, Alexandra B; Sagawa, Janelle M; Stanley, Lauren E; Bradshaw, Harvey D

    2016-03-01

    Flower color patterns have long served as a model for developmental genetics because pigment phenotypes are visually striking, yet generally not required for plant viability, facilitating the genetic analysis of color and pattern mutants. The evolution of novel flower colors and patterns has played a key role in the adaptive radiation of flowering plants via their specialized interactions with different pollinator guilds (e.g., bees, butterflies, birds), motivating the search for allelic differences affecting flower color pattern in closely related plant species with different pollinators. We have identified LIGHT AREAS1 (LAR1), encoding an R2R3-MYB transcription factor, as the causal gene underlying the spatial pattern variation of floral anthocyanin pigmentation between two sister species of monkeyflower: the bumblebee-pollinated Mimulus lewisii and the hummingbird-pollinated Mimulus cardinalis. We demonstrated that LAR1 positively regulates FLAVONOL SYNTHASE (FLS), essentially eliminating anthocyanin biosynthesis in the white region (i.e., light areas) around the corolla throat of M. lewisii flowers by diverting dihydroflavonol into flavonol biosynthesis from the anthocyanin pigment pathway. FLS is preferentially expressed in the light areas of the M. lewisii flower, thus prepatterning the corolla. LAR1 expression in M. cardinalis flowers is much lower than in M. lewisii, explaining the unpatterned phenotype and recessive inheritance of the M. cardinalis allele. Furthermore, our gene-expression analysis and genetic mapping results suggest that cis-regulatory change at the LAR1 gene played a critical role in the evolution of different pigmentation patterns between the two species. PMID:26884205

  10. Competition between anthocyanin and flavonol biosynthesis produces spatial pattern variation of floral pigments between Mimulus species

    PubMed Central

    Yuan, Yao-Wu; Rebocho, Alexandra B.; Sagawa, Janelle M.; Stanley, Lauren E.; Bradshaw, Harvey D.

    2016-01-01

    Flower color patterns have long served as a model for developmental genetics because pigment phenotypes are visually striking, yet generally not required for plant viability, facilitating the genetic analysis of color and pattern mutants. The evolution of novel flower colors and patterns has played a key role in the adaptive radiation of flowering plants via their specialized interactions with different pollinator guilds (e.g., bees, butterflies, birds), motivating the search for allelic differences affecting flower color pattern in closely related plant species with different pollinators. We have identified LIGHT AREAS1 (LAR1), encoding an R2R3-MYB transcription factor, as the causal gene underlying the spatial pattern variation of floral anthocyanin pigmentation between two sister species of monkeyflower: the bumblebee-pollinated Mimulus lewisii and the hummingbird-pollinated Mimulus cardinalis. We demonstrated that LAR1 positively regulates FLAVONOL SYNTHASE (FLS), essentially eliminating anthocyanin biosynthesis in the white region (i.e., light areas) around the corolla throat of M. lewisii flowers by diverting dihydroflavonol into flavonol biosynthesis from the anthocyanin pigment pathway. FLS is preferentially expressed in the light areas of the M. lewisii flower, thus prepatterning the corolla. LAR1 expression in M. cardinalis flowers is much lower than in M. lewisii, explaining the unpatterned phenotype and recessive inheritance of the M. cardinalis allele. Furthermore, our gene-expression analysis and genetic mapping results suggest that cis-regulatory change at the LAR1 gene played a critical role in the evolution of different pigmentation patterns between the two species. PMID:26884205

  11. Multi-substrate flavonol O-glucosyltransferases from strawberry (Fragaria x ananassa) achene and receptacle.

    PubMed

    Griesser, Markus; Vitzthum, Florian; Fink, Barbara; Bellido, Mari Luz; Raasch, Constanze; Munoz-Blanco, Juan; Schwab, Wilfried

    2008-01-01

    In an effort to characterize fruit ripening-related genes functionally, two glucosyltransferases, FaGT6 and FaGT7, were cloned from a strawberry (Fragaria x ananassa) cDNA library and the full-length open reading frames were amplified by rapid amplification of cDNA ends. FaGT6 and FaGT7 were expressed heterologously as fusion proteins in Escherichia coli and target protein was purified using affinity chromatography. Both recombinant enzymes exhibited a broad substrate tolerance in vitro, accepting numerous flavonoids, hydroxycoumarins, and naphthols. FaGT6 formed 3-O-glucosides and minor amounts of 7-O-, 4'-O-, and 3'-O-monoglucosides and one diglucoside from flavonols such as quercetin. FaGT7 converted quercetin to the 3-O-glucoside and 4'-O-glucoside and minor levels of the 7- and 3'-isomers but formed no diglucoside. Gene expression studies showed that both genes are strongly expressed in achenes of small-sized green fruits, while the expression levels were generally lower in the receptacle. Significant levels of quercetin 3-O-, 7-O-, and 4'-O-glucosides, kaempferol 3-O- and 7-O-glucosides, as well as isorhamnetin 7-O-glucoside, were identified in achenes and the receptacle. In the receptacle, the expression of both genes is negatively controlled by auxin which correlates with the ripening-related gene expression in this tissue. Salicylic acid, a known signal molecule in plant defence, induces the expression of both genes. Thus, it appears that FaGT6 and FaGT7 are involved in the glucosylation of flavonols and may also participate in xenobiotic metabolism. The latter function is supported by the proven ability of strawberries to glucosylate selected unnatural substrates injected in ripe fruits. This report presents the first biochemical characterization of enzymes mainly expressed in strawberry achenes and provides the foundation of flavonoid metabolism in the seeds. PMID:18487633

  12. A R2R3-MYB Transcription Factor Regulates the Flavonol Biosynthetic Pathway in a Traditional Chinese Medicinal Plant, Epimedium sagittatum.

    PubMed

    Huang, Wenjun; Khaldun, A B M; Chen, Jianjun; Zhang, Chanjuan; Lv, Haiyan; Yuan, Ling; Wang, Ying

    2016-01-01

    Flavonols as plant secondary metabolites with vital roles in plant development and defense against UV light, have been demonstrated to be the main bioactive components (BCs) in the genus Epimedium plants, several species of which are used as materials for Herba Epimedii, an important traditional Chinese medicine. The flavonol biosynthetic pathway genes had been already isolated from Epimedium sagittatum, but a R2R3-MYB transcription factor regulating the flavonol synthesis has not been functionally characterized so far in Epimedium plants. In this study, we isolated and characterized the R2R3-MYB transcription factor EsMYBF1 involved in regulation of the flavonol biosynthetic pathway from E. sagittatum. Sequence analysis indicated that EsMYBF1 belongs to the subgroup 7 of R2R3-MYB family which contains the flavonol-specific MYB regulators identified to date. Transient reporter assay showed that EsMYBF1 strongly activated the promoters of EsF3H (flavanone 3-hydroxylase) and EsFLS (flavonol synthase), but not the promoters of EsDFRs (dihydroflavonol 4-reductase) and EsANS (anthocyanidin synthase) in transiently transformed Nicotiana benthamiana leaves. Both yeast two-hybrid assay and transient reporter assay validated EsMYBF1 to be independent of EsTT8, or AtTT8 bHLH regulators of the flavonoid pathway as cofactors. Ectopic expression of EsMYBF1 in transgenic tobacco resulted in the increased flavonol content and the decreased anthocyanin content in flowers. Correspondingly, the structural genes involved in flavonol synthesis were upregulated in the EsMYBF1 overexpression lines, including NtCHS (chalcone synthase), NtCHI (chalcone isomerase), NtF3H and NtFLS, whereas the late biosynthetic genes of the anthocyanin pathway (NtDFR and NtANS) were remarkably downregulated, compared to the controls. These results suggest that EsMYBF1 is a flavonol-specific R2R3-MYB regulator, and involved in regulation of the biosynthesis of the flavonol-derived BCs in E. sagittatum. Thus

  13. A R2R3-MYB Transcription Factor Regulates the Flavonol Biosynthetic Pathway in a Traditional Chinese Medicinal Plant, Epimedium sagittatum

    PubMed Central

    Huang, Wenjun; Khaldun, A. B. M.; Chen, Jianjun; Zhang, Chanjuan; Lv, Haiyan; Yuan, Ling; Wang, Ying

    2016-01-01

    Flavonols as plant secondary metabolites with vital roles in plant development and defense against UV light, have been demonstrated to be the main bioactive components (BCs) in the genus Epimedium plants, several species of which are used as materials for Herba Epimedii, an important traditional Chinese medicine. The flavonol biosynthetic pathway genes had been already isolated from Epimedium sagittatum, but a R2R3-MYB transcription factor regulating the flavonol synthesis has not been functionally characterized so far in Epimedium plants. In this study, we isolated and characterized the R2R3-MYB transcription factor EsMYBF1 involved in regulation of the flavonol biosynthetic pathway from E. sagittatum. Sequence analysis indicated that EsMYBF1 belongs to the subgroup 7 of R2R3-MYB family which contains the flavonol-specific MYB regulators identified to date. Transient reporter assay showed that EsMYBF1 strongly activated the promoters of EsF3H (flavanone 3-hydroxylase) and EsFLS (flavonol synthase), but not the promoters of EsDFRs (dihydroflavonol 4-reductase) and EsANS (anthocyanidin synthase) in transiently transformed Nicotiana benthamiana leaves. Both yeast two-hybrid assay and transient reporter assay validated EsMYBF1 to be independent of EsTT8, or AtTT8 bHLH regulators of the flavonoid pathway as cofactors. Ectopic expression of EsMYBF1 in transgenic tobacco resulted in the increased flavonol content and the decreased anthocyanin content in flowers. Correspondingly, the structural genes involved in flavonol synthesis were upregulated in the EsMYBF1 overexpression lines, including NtCHS (chalcone synthase), NtCHI (chalcone isomerase), NtF3H and NtFLS, whereas the late biosynthetic genes of the anthocyanin pathway (NtDFR and NtANS) were remarkably downregulated, compared to the controls. These results suggest that EsMYBF1 is a flavonol-specific R2R3-MYB regulator, and involved in regulation of the biosynthesis of the flavonol-derived BCs in E. sagittatum. Thus

  14. Oral bioavailability of quercetin from different quercetin glycosides in dogs.

    PubMed

    Reinboth, Marianne; Wolffram, Siegfried; Abraham, Getu; Ungemach, Fritz R; Cermak, Rainer

    2010-07-01

    Although the flavonol quercetin is used as a supplement in commercial dog food, data on quercetin bioavailability in dogs are not available. Thus, we investigated quercetin bioavailability (measured as area under the concentration-time curve) in nine adult beagle dogs at an oral dose of 10 mg/kg body weight (b.w.). The major fraction (>80 %) of flavonols circulating in blood plasma were conjugated metabolites of quercetin. The absolute bioavailability of quercetin (i.e. the fraction that reaches the systemic circulation) was only about 4 %. We also compared the oral bioavailability between the aglycone quercetin and its more often used glucorhamnoside (rutin) and 3-O-glucoside (isoquercitrin) at an equimolar dose of 30 mumol/kg b.w. (corresponding to 10 mg quercetin/kg). Quercetin and isoquercitrin were mainly absorbed in the small intestine with isoquercitrin being one and a half times more bioavailable than quercetin. Maximal plasma concentration after isoquercitrin treatment was 0.89 (sem 0.07) mumol/l. Although quercetin absorption from rutin was delayed, relative bioavailability was not lower than from the aglycone itself. The latter observation is in clear contrast to findings in human subjects, pigs or rats and might indicate that rutin is a better source of quercetin in dogs than in other species. However, potential in vivo quercetin effects beyond the gastrointestinal tract are limited by the intensive metabolism as well as by the rather low bioavailability of this flavonol.

  15. Resin Glycosides from the Morning Glory Family

    NASA Astrophysics Data System (ADS)

    Pereda-Miranda, Rogelio; Rosas-Ramírez, Daniel; Castañeda-Gómez, Jhon

    Resin glycosides are part of a very extensive family of secondary metabolites known as glycolipids or lipo-oligosaccharides and are constituents of complex resins (glycoresins) (1) unique to the morning glory family, Convolvulaceae (2). These active principles are responsible for the drastic purgative action of all the important Convolvulaceous species used in traditional medicine throughout the world since ancient times. Several commercial purgative crude drugs can be prepared from the roots of different species of Mexican morning glories. Their incorporation as therapeutic agents in Europe is an outstanding example of the assimilation of botanical drugs from the Americas as substitutes for traditional Old World remedies (3). Even though phytochemical investigations on the constituents of these drugs were initiated during the second half of the nineteenth century, the structure of their active ingredients still remains poorly known for some examples of these purgative roots. During the last two decades, the higher resolution capabilities of modern analytical isolation techniques used in conjunction with powerful spectroscopic methods have facilitated the elucidation of the active principles of these relevant herbal products.

  16. Glycosidic inhibitors of melanogenesis from leaves of Passiflora edulis.

    PubMed

    Zhang, Jie; Koike, Ryosuke; Yamamoto, Ayako; Ukiya, Motohiko; Fukatsu, Makoto; Banno, Norihiro; Miura, Motofumi; Motohashi, Shigeyasu; Tokuda, Harukuni; Akihisa, Toshihiro

    2013-10-01

    A new flavonoid glycoside, chrysin 6-C-β-rutinoside (chrysin α-L-rhamnopyranosyl-(1→6)-C-β-glucopyranoside; 2), and two new triterpene glycosides, (31R)-31-O-methylpassiflorine (7) and (31S)-31-O-methylpassiflorine (8), along with 14 known glycosides, including three flavonoid glycosides, 1, 3, and 4, six triterpene glycosides, 5, 6, and 9-12, three cyano glycosides, 13-15, and two other glycosides, 16 and 17, were isolated from a MeOH extract of the leaves of Passiflora edulis (passion flower; Passifloraceae). The structures of new compounds were elucidated on the basis of extensive spectroscopic analysis and comparison with literature data. Upon evaluation of compounds 1-17 against the melanogenesis in the B16 melanoma cells induced with α-melanocyte-stimulating hormone (α-MSH), three compounds, isoorientin (1), 2, and (6S,9R)-roseoside (17), exhibited inhibitory effects with 37.3-47.2% reduction of melanin content with no, or almost no, toxicity to the cells (90.8-100.2% cell viability) at 100 μM. Western blot analysis showed that compound 2 reduced the protein levels of MITF, TRP-1, and tyrosinase, in a concentration-dependent manner while exerted almost no influence on the level of TRP-2, suggesting that this compound inhibits melanogenesis on the α-MSH-stimulated B16 melanoma cells by, at least in part, inhibiting the expression of MITF, followed by decreasing the expression of TRP-1 and tyrosinase. In addition, compounds 1-17 were evaluated for their inhibitory effects against the EpsteinBarr virus early antigen (EBV-EA) activation induced by 12-O-tetradecanoylphorbol-13-acetate (TPA) in Raji cells. PMID:24130028

  17. Amine, Alcohol and Phosphine Catalysts for Acyl Transfer Reactions

    NASA Astrophysics Data System (ADS)

    Spivey, Alan C.; Arseniyadis, Stellios

    An overview of the area of organocatalytic asymmetric acyl transfer processes is presented including O- and N-acylation. The material has been ordered according to the structural class of catalyst employed rather than reaction type with the intention to draw mechanistic parallels between the manner in which the various reactions are accelerated by the catalysts and the concepts employed to control transfer of chiral information from the catalyst to the substrates.

  18. Dietary Flavonols Intake and Risk of Esophageal and Gastric Cancer: A Meta-Analysis of Epidemiological Studies

    PubMed Central

    Xie, Yan; Huang, Shifeng; Su, Yuxi

    2016-01-01

    Background: Esophageal cancer (EC) and gastric cancer (GC) are common cancers and leading causes of cancer deaths worldwide. Many studies have investigated the association between dietary flavonols intake and the risk of EC and GC, but the results are inconsistent. Hence, we conducted a systematic analysis of relevant population-based studies to assess the association and derive a more precise estimation. Methods: The Cochrane, PubMed and Embase databases were searched to identify articles published through January 2016 that met the predetermined inclusion criterion. Twelve studies involving 4593 patients and 519,378 controls were included. Results: The summary odds ratios (ORs) of EC, GC and the two combined were respectively 0.88 (95% CI: 0.73–1.08), 0.80 (95% CI: 0.70–0.91) and 0.83 (95% CI: 0.74–0.92) for the highest category of dietary flavonols intake compared with the lowest. No significant heterogeneities were observed in these studies. Further analysis showed that the pooled ORs of EC and GC for cohort, population-based case-control and hospital-based case-control studies were 0.90 (95% CI: 0.61–1.34), 0.92 (95% CI: 0.72–1.18), 0.68 (95% CI: 0.38–1.24) and 0.83 (95% CI: 0.65–1.06), 0.84 (95% CI: 0.45–1.59), 0.70 (95% CI: 0.56–0.88). The subgroup analyses revealed a significant association of flavonol intake with a reduced risk of noncardia gastric adenocarcinoma but not gastric cardia adenocarcinoma. Moreover, significant inverse associations of flavonol intake with GC risk were observed in women but not in men, in smokers but not in nonsmokers, in European populations but not in American populations. Similarly, a significant inverse association of flavonols intake with EC risk was also observed in smokers but not in nonsmokers. Conclusion: High intake of dietary flavonols is significantly related to a reduced risk of GC, especially in women and smokers. PMID:26891324

  19. Possible Role of Different Yeast and Plant Lysophospholipid:Acyl-CoA Acyltransferases (LPLATs) in Acyl Remodelling of Phospholipids.

    PubMed

    Jasieniecka-Gazarkiewicz, Katarzyna; Demski, Kamil; Lager, Ida; Stymne, Sten; Banaś, Antoni

    2016-01-01

    Recent results have suggested that plant lysophosphatidylcholine:acyl-coenzyme A acyltransferases (LPCATs) can operate in reverse in vivo and thereby catalyse an acyl exchange between the acyl-coenzyme A (CoA) pool and the phosphatidylcholine. We have investigated the abilities of Arabidopsis AtLPCAT2, Arabidopsis lysophosphatidylethanolamine acyltransferase (LPEAT2), S. cerevisiae lysophospholipid acyltransferase (Ale1) and S. cerevisiae lysophosphatidic acid acyltransferase (SLC1) to acylate lysoPtdCho, lysoPtdEtn and lysoPtdOH and act reversibly on the products of the acylation; the PtdCho, PtdEtn and PtdOH. The tested LPLATs were expressed in an S. cervisiae ale1 strain and enzyme activities were assessed in assays using microsomal preparations of the different transformants. The results show that, despite high activity towards lysoPtdCho, lysoPtdEtn and lysoPtdOH by the ALE1, its capacities to operate reversibly on the products of the acylation were very low. Slc1 readily acylated lysoPtdOH, lysoPtdCho and lysoPtdEtn but showed no reversibility towards PtdCho, very little reversibility towards PtdEtn and very high reversibility towards PtdOH. LPEAT2 showed the highest levels of reversibility towards PtdCho and PtdEtn of all LPLATs tested but low ability to operate reversibly on PtdOH. AtLPCAT2 showed good reversible activity towards PtdCho and PtdEtn and very low reversibility towards PtdOH. Thus, it appears that some of the LPLATs have developed properties that, to a much higher degree than other LPLATs, promote the reverse reaction during the same assay conditions and with the same phospholipid. The results also show that the capacity of reversibility can be specific for a particular phospholipid, albeit the lysophospholipid derivatives of other phospholipids serve as good acyl acceptors for the forward reaction of the enzyme. PMID:26643989

  20. Characterization of a recently evolved flavonol-phenylacyltransferase gene provides signatures of natural light selection in Brassicaceae

    PubMed Central

    Tohge, Takayuki; Wendenburg, Regina; Ishihara, Hirofumi; Nakabayashi, Ryo; Watanabe, Mutsumi; Sulpice, Ronan; Hoefgen, Rainer; Takayama, Hiromitsu; Saito, Kazuki; Stitt, Mark; Fernie, Alisdair R.

    2016-01-01

    Incidence of natural light stress renders it important to enhance our understanding of the mechanisms by which plants protect themselves from harmful effects of UV-B irradiation, as this is critical for fitness of land plant species. Here we describe natural variation of a class of phenylacylated-flavonols (saiginols), which accumulate to high levels in floral tissues of Arabidopsis. They were identified in a subset of accessions, especially those deriving from latitudes between 16° and 43° North. Investigation of introgression line populations using metabolic and transcript profiling, combined with genomic sequence analysis, allowed the identification of flavonol-phenylacyltransferase 2 (FPT2) that is responsible for the production of saiginols and conferring greater UV light tolerance in planta. Furthermore, analysis of polymorphism within the FPT duplicated region provides an evolutionary framework of the natural history of this locus in the Brassicaceae. PMID:27545969

  1. Characterization of a recently evolved flavonol-phenylacyltransferase gene provides signatures of natural light selection in Brassicaceae.

    PubMed

    Tohge, Takayuki; Wendenburg, Regina; Ishihara, Hirofumi; Nakabayashi, Ryo; Watanabe, Mutsumi; Sulpice, Ronan; Hoefgen, Rainer; Takayama, Hiromitsu; Saito, Kazuki; Stitt, Mark; Fernie, Alisdair R

    2016-01-01

    Incidence of natural light stress renders it important to enhance our understanding of the mechanisms by which plants protect themselves from harmful effects of UV-B irradiation, as this is critical for fitness of land plant species. Here we describe natural variation of a class of phenylacylated-flavonols (saiginols), which accumulate to high levels in floral tissues of Arabidopsis. They were identified in a subset of accessions, especially those deriving from latitudes between 16° and 43° North. Investigation of introgression line populations using metabolic and transcript profiling, combined with genomic sequence analysis, allowed the identification of flavonol-phenylacyltransferase 2 (FPT2) that is responsible for the production of saiginols and conferring greater UV light tolerance in planta. Furthermore, analysis of polymorphism within the FPT duplicated region provides an evolutionary framework of the natural history of this locus in the Brassicaceae. PMID:27545969

  2. MK571 inhibits phase-2 conjugation of flavonols by Caco-2/TC7 cells, but does not specifically inhibit their apical efflux☆

    PubMed Central

    Barrington, Robert D.; Needs, Paul W.; Williamson, Gary; Kroon, Paul A.

    2015-01-01

    MK571 is a multidrug resistance protein-2 (ABCC2, Mrp2) inhibitor and has been widely used to demonstrate the role of Mrp2 in the cellular efflux of drugs, xenobiotics and their conjugates. Numerous reports have described modulation of Caco-2 cellular efflux and transport of flavonoids in the presence of MK571. Since flavonoids are efficiently conjugated by Caco-2/TC7 cells, we investigated the effects of MK571 on the efflux of flavonoid conjugates. The flavonol aglycones kaempferol, quercetin and galangin were efficiently taken up, conjugated and effluxed by Caco-2/TC7 cells. Apically-applied MK571 caused significant reductions in both the apical and basolateral efflux of flavonol conjugates from Caco-2/TC7 monolayers. MK571 did not significantly alter the apical:basolateral efflux ratio for flavonol conjugates, however, which is not consistent with MK571 specifically inhibiting only apical Mrp2. Since MK571 decreased the total amounts of conjugates formed, and increased cellular flavonol aglycone concentrations, we explored the possibility that MK571 also inhibits phase-2 conjugation of flavonols. MK571 dose-dependently inhibited the intracellular biosynthesis of all flavonol glucuronides and sulphates by Caco-2 cells. MK571 significantly inhibited phase-2 conjugation of kaempferol by cell-free extracts of Caco-2, and production of kaempferol-4′-O-glucuronide was competitively inhibited. These data show that MK571, in addition to inhibiting MRP2, is a potential inhibitor of enterocyte phase-2 conjugation. PMID:25801004

  3. Monogalactosyldiacylglycerol biosynthesis by direct acyl transfer in Anabaena variabilis. [Anabaena variabilis

    SciTech Connect

    Chen, H.H.; Wickrema, A.; Jaworski, J.

    1987-05-01

    The authors previously reported the direct acylation of monogalactosyldiacylglycerol (MGDG) by an enzyme in the membranes of the cyanobacterium (Anabaena variabilis. The enzyme requires acyl-acyl carrier protein (acyl-ACP) as substrate, but had no other additional cofactor requirements. Palmitoyl-, stearoyl- and oleoyl-ACP were all effective substrates. The A. variabilis membranes also had a hydrolase activity which metabolized the acyl-ACP to yield free fatty acid and ACP. Possible mechanisms for the acylation reaction include either acyl exchange with existing MGDG or direct acyl transfer to a lyso-MGDG, with concomitant release of free ACP. The mechanism of this reaction has been resolved using a double labelled (/sup 14/C)acyl-(/sup 14/C)ACP substrate prepared with E. coli acyl-ACP synthetase. Following incubation with the enzyme, the unreacted (/sup 14/C)acyl-(/sup 14/C)ACP was isolated and the (/sup 14/C)acyl/(/sup 14/C)ACP ratio determined. Comparison of this ratio to that of the original substrate indicated no change and eliminated acyl exchange as a possible mechanism. Therefore, the direct acylation of lyso-MGDG is the proposed mechanism for this enzyme. The reaction is apparently specific for MGDG synthesis, as other glycolipids and phospholipids were not labelled during incubations.

  4. Multi-substrate flavonol O-glucosyltransferases from strawberry (Fragaria×ananassa) achene and receptacle

    PubMed Central

    Griesser, Markus; Vitzthum, Florian; Fink, Barbara; Bellido, Mari Luz; Raasch, Constanze; Munoz-Blanco, Juan; Schwab, Wilfried

    2008-01-01

    In an effort to characterize fruit ripening-related genes functionally, two glucosyltransferases, FaGT6 and FaGT7, were cloned from a strawberry (Fragaria×ananassa) cDNA library and the full-length open reading frames were amplified by rapid amplification of cDNA ends. FaGT6 and FaGT7 were expressed heterologously as fusion proteins in Escherichia coli and target protein was purified using affinity chromatography. Both recombinant enzymes exhibited a broad substrate tolerance in vitro, accepting numerous flavonoids, hydroxycoumarins, and naphthols. FaGT6 formed 3-O-glucosides and minor amounts of 7-O-, 4′-O-, and 3′-O-monoglucosides and one diglucoside from flavonols such as quercetin. FaGT7 converted quercetin to the 3-O-glucoside and 4′-O-glucoside and minor levels of the 7- and 3′-isomers but formed no diglucoside. Gene expression studies showed that both genes are strongly expressed in achenes of small-sized green fruits, while the expression levels were generally lower in the receptacle. Significant levels of quercetin 3-O-, 7-O-, and 4′-O-glucosides, kaempferol 3-O- and 7-O-glucosides, as well as isorhamnetin 7-O-glucoside, were identified in achenes and the receptacle. In the receptacle, the expression of both genes is negatively controlled by auxin which correlates with the ripening-related gene expression in this tissue. Salicylic acid, a known signal molecule in plant defence, induces the expression of both genes. Thus, it appears that FaGT6 and FaGT7 are involved in the glucosylation of flavonols and may also participate in xenobiotic metabolism. The latter function is supported by the proven ability of strawberries to glucosylate selected unnatural substrates injected in ripe fruits. This report presents the first biochemical characterization of enzymes mainly expressed in strawberry achenes and provides the foundation of flavonoid metabolism in the seeds. PMID:18487633

  5. Complexation of alkyl glycosides with α-cyclodextrin can have drastically different effects on their conversion by glycoside hydrolases.

    PubMed

    Rather, Mohd Younis; Nordberg Karlsson, Eva; Adlercreutz, Patrick

    2015-04-20

    Substrates present in aggregated forms, such as micelles, are often poorly converted by enzymes. Alkyl glycosides constitute typical examples and the critical micelle concentration (CMC) decreases with increasing length of the alkyl group. In this study, possibilities to hydrolyse alkyl glycosides by glycoside hydrolases were explored, and α-cyclodextrin was used as an agent to form inclusion complexes with the alkyl glycosides, thereby preventing micelle formation. The cyclodextrin complexes were accepted as substrates by the enzymes to variable extent. The β-glucosidases originating from Thermotoga neapolitana (Tn Bgl3B) and from almond were not at all able to hydrolyse alkyl β-glucosides in the presence of 100mM α-cyclodextrin. However, Aspergillus niger amyloglucosidase readily accepted the complexes as substrates. In reactions involving decyl and dodecyl maltosides, the presence of 100mM α-cyclodextrin caused an increase in reaction rate in most cases, especially at high substrate concentrations. Surprisingly, the amyloglucosidase-catalyzed hydrolysis of octyl-β-maltoside to glucose and β-octylglucoside was faster in the presence of α-cyclodextrin than without, even at substrate concentrations below CMC. A possible explanation of the observed rate enhancement is that binding sites on the carbohydrate binding domain of amyloglucosidase, known to bind cyclodextrins, help to guide the alkyl glycoside-cyclodextrin complex to the active site, and thereby promote its conversion.

  6. Automated assembly of oligosaccharides containing multiple cis-glycosidic linkages

    NASA Astrophysics Data System (ADS)

    Hahm, Heung Sik; Hurevich, Mattan; Seeberger, Peter H.

    2016-09-01

    Automated glycan assembly (AGA) has advanced from a concept to a commercial technology that rapidly provides access to diverse oligosaccharide chains as long as 30-mers. To date, AGA was mainly employed to incorporate trans-glycosidic linkages, where C2 participating protecting groups ensure stereoselective couplings. Stereocontrol during the installation of cis-glycosidic linkages cannot rely on C2-participation and anomeric mixtures are typically formed. Here, we demonstrate that oligosaccharides containing multiple cis-glycosidic linkages can be prepared efficiently by AGA using monosaccharide building blocks equipped with remote participating protecting groups. The concept is illustrated by the automated syntheses of biologically relevant oligosaccharides bearing various cis-galactosidic and cis-glucosidic linkages. This work provides further proof that AGA facilitates the synthesis of complex oligosaccharides with multiple cis-linkages and other biologically important oligosaccharides.

  7. Temperature dependent vibrational modes of glycosidic bond in disaccharide sugars.

    PubMed

    Seo, Jeong-Ah; Kwon, Hyun-Joung; Kim, Hyung Kook; Hwang, Yoon-Hwae

    2008-03-17

    We studied the temperature dependent vibrational modes of the glycosidic bond in trehalose, sucrose, and maltose at wavenumbers ranging from 1000 to 1200 cm(-1). We found that the slope of temperature dependent Raman shifts of the glycosidic bond in trehalose and sucrose changed at temperatures around 120 degrees C, indicating a bond length or a bond angle (dihedral and torsional angles) change. However, we did not observe any slope change in maltose because the melting temperature of maltose is very close to 120 degrees C. We also found, at temperatures below 120 degrees C, that Raman shifts of the vibrational modes of the glycosidic bond in trehalose showed the strongest temperature dependence among the three disaccharides.

  8. 2-methyl-L-erythritol glycosides from Gardenia jasminoides.

    PubMed

    Yang, Liguo; Peng, Kaifeng; Zhao, Shizhe; Zhao, Feng; Chen, Lixia; Qiu, Feng

    2013-09-01

    Two new glycosides, 2-methyl-L-erythritol-4-O-(6-O-trans-sinapoyl)-β-D-glucopyranoside (1) and 2-methyl-L-erythritol-1-O-(6-O-trans-sinapoyl)-β-D-glucopyranoside (2), along with two known triterpenoids (3-4), four quinic acid derivatives (5-8) and one flavonoid (9) were isolated from the fruit of Gardenia jasminoides. Their structures were elucidated through MS and 2D NMR experiments (HMQC and HMBC). Inhibitory effects of the isolated compounds on nitric oxide production in lipopolysaccharide-activated macrophages were evaluated. Though 2-methyl-D-erythritol and its glycosides have been reported in a few references, this is the first report about 2-methyl-L-erythritol glycosides. Based on this finding, we propose that 2-methyl-L-erythritol might be a new intermediate in the non-mevalonate biosynthesis of terpenoids.

  9. Automated assembly of oligosaccharides containing multiple cis-glycosidic linkages

    PubMed Central

    Hahm, Heung Sik; Hurevich, Mattan; Seeberger, Peter H

    2016-01-01

    Automated glycan assembly (AGA) has advanced from a concept to a commercial technology that rapidly provides access to diverse oligosaccharide chains as long as 30-mers. To date, AGA was mainly employed to incorporate trans-glycosidic linkages, where C2 participating protecting groups ensure stereoselective couplings. Stereocontrol during the installation of cis-glycosidic linkages cannot rely on C2-participation and anomeric mixtures are typically formed. Here, we demonstrate that oligosaccharides containing multiple cis-glycosidic linkages can be prepared efficiently by AGA using monosaccharide building blocks equipped with remote participating protecting groups. The concept is illustrated by the automated syntheses of biologically relevant oligosaccharides bearing various cis-galactosidic and cis-glucosidic linkages. This work provides further proof that AGA facilitates the synthesis of complex oligosaccharides with multiple cis-linkages and other biologically important oligosaccharides. PMID:27580973

  10. Automated assembly of oligosaccharides containing multiple cis-glycosidic linkages.

    PubMed

    Hahm, Heung Sik; Hurevich, Mattan; Seeberger, Peter H

    2016-01-01

    Automated glycan assembly (AGA) has advanced from a concept to a commercial technology that rapidly provides access to diverse oligosaccharide chains as long as 30-mers. To date, AGA was mainly employed to incorporate trans-glycosidic linkages, where C2 participating protecting groups ensure stereoselective couplings. Stereocontrol during the installation of cis-glycosidic linkages cannot rely on C2-participation and anomeric mixtures are typically formed. Here, we demonstrate that oligosaccharides containing multiple cis-glycosidic linkages can be prepared efficiently by AGA using monosaccharide building blocks equipped with remote participating protecting groups. The concept is illustrated by the automated syntheses of biologically relevant oligosaccharides bearing various cis-galactosidic and cis-glucosidic linkages. This work provides further proof that AGA facilitates the synthesis of complex oligosaccharides with multiple cis-linkages and other biologically important oligosaccharides. PMID:27580973

  11. Studies on the flavone glycosides from Fructus Kochiae.

    PubMed

    Xu, Yun-Hui; Huang, Hao; Zhang, Nian; Kong, De-Yun; Hua, Mo-Li

    2014-01-01

    A series of flavone glycosides were isolated from Fructus Kochiae for the first time, including two new flavone glycosides. The structures were established by interpretation of their spectroscopic data. Two new flavone glycosides are quercetin 3-O-β-d-apiofuranosyl-(1 → 2)-β-d-galactopyranosyl-7-O-β-d-glucopyranoside (1) and quercetin 3-O-α-l-rhamnopyranosyl-(1 → 6)-β-d-galactopyranosyl-7-O-β-d-sophoroside (2). The others are quercetin 7-O-β-d-glucopyranoside (3), quercetin 3-O-β-d-apiofuranosyl-(1 → 2)-β-d-galactopyranoside (4), quercetin 3-O-β-d-galactopyranosyl-7-O-β-d-glucopyranoside (5), and quercetin 7-O-β-d-sophoroside (6). PMID:23919635

  12. Sesquiterpene glycosides from the roots of Codonopsis pilosula

    PubMed Central

    Jiang, Yueping; Liu, Yufeng; Guo, Qinglan; Xu, Chengbo; Zhu, Chenggen; Shi, Jiangong

    2015-01-01

    Three new sesquiterpene glycosides, named codonopsesquilosides A−C (1−3), were isolated from an aqueous extract of the dried roots of Codonopsis pilosula. Their structures including absolute configurations were determined by spectroscopic and chemical methods. These glycosides are categorized as C15 carotenoid (1), gymnomitrane (2), and eudesmane (3) types of sesquiterpenoids, respectively. Compound 1 is the first diglycoside of C15 carotenoids to be reported. Compound 2 represents the second reported example of gymnomitrane-type sesquiterpenoids from higher plants. The absolute configurations were supported by comparison of the experimental circular dichroism (CD) spectra with the calculated electronic CD (ECD) spectra of 1−3, their aglycones, and model compounds based on quantum-mechanical time-dependent density functional theory. The influences of the glycosyls on the calculated ECD spectra of the glycosidic sesquiterpenoids, as well as some nomenclature and descriptive problems with gymnomitrane-type sesquiterpenoids are discussed. PMID:26904398

  13. Cytotoxic sulfated triterpene glycosides from the sea cucumber Pseudocolochirus violaceus.

    PubMed

    Zhang, Shu-Yu; Yi, Yang-Hua; Tang, Hai-Feng

    2006-07-01

    Bioassay-guided fractionation of the active BuOH extract of the sea cucumber Pseudocolochirus violaceus resulted in the isolation of three new sulfated triterpene glycosides, i.e., violaceusides I, II, and III (1-3, resp.), as active compounds causing morphological abnormality of Pyricularia oryzae mycelia. Their structures were elucidated by spectroscopic methods including 2D-NMR and MS experiments, as well as chemical evidence. Compounds 1-3 exhibit the same structural features, i.e., the presence of a 16-oxo group in the holostane-type triterpene aglycone with the C(7)=C(8) bond, but differ in the side chains and the tetrasaccharide moieties. Compound 1 possesses one sulfate group, while 2 and 3 are disulfated glycosides. All the glycosides showed significant in vitro cytotoxicities against human gastric cancer MKN-45 and human colon cancer HCT-116 cells. PMID:17193313

  14. Bioactive triterpene glycosides from the sea cucumber Holothuria fuscocinerea.

    PubMed

    Zhang, Shu-Yu; Yi, Yang-Hua; Tang, Hai-Feng

    2006-10-01

    Bioassay-guided fractionation of the active n-BuOH extract of the sea cucumber Holothuria fuscocinerea resulted in the isolation of three new triterpene glycosides, fuscocinerosides A (1), B (2), and C (3), along with two known glycosides, pervicoside C (4) and holothurin A (5), as active compounds causing morphological abnormality of Pyricularia oryzae mycelia. Compounds 1-5 possess the same tetrasaccharide moiety, 3-O-methyl-beta-D-glucopyranosyl-(1-->3)-beta-D- glucopyranosyl-(1-->4)-beta-D-quinovopyranosyl-(1-->2)-4-O-sodiumsulfato-beta-D-xylopyranosyl, linked to C-3 of holostane triterpene aglycones that differ in their side chains and 17-substituents. Their structures were elucidated by extensive spectral studies as well as chemical evidence. All the glycosides showed in vitro cytotoxicity against two human tumor cell lines. PMID:17067169

  15. Ecdysteroid glycosides: identification, chromatographic properties, and biological significance.

    PubMed

    Maria, Annick; Girault, Jean-Pierre; Saatov, Ziyadilla; Harmatha, Juraj; Dinan, Laurence; Lafont, René

    2005-03-01

    Ecdysteroid glycosides are found in both animals and plants. The chromatographic behavior of these molecules is characteristic, as they appear much more polar than their corresponding free aglycones when analyzed by normal-phase high-performance liquid chromatography (HPLC), whereas the presence of glycosidic moieties has a very limited (if any) impact on polarity when using reversed-phase HPLC. Biological activity is greatly reduced because the presence of this bulky substituent probably impairs the interaction with ecdysteroid receptor(s). 2-Deoxy-20-hydroxyecdysone 22-O-beta-D-glucopyranoside, which has been isolated from the dried aerial parts of Silene nutans (Caryophyllaceae), is used as a model compound to describe the rationale of ecdysteroid glycoside purification and identification.

  16. Nickel-catalyzed proton-deuterium exchange (HDX) procedures for glycosidic linkage analysis of complex carbohydrates

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The structural analysis of complex carbohydrates typically requires the assignment of three parameters: monosaccharide composition, the position of glycosidic linkages between monosaccharides, and the position and nature of non-carbohydrate substituents. The glycosidic linkage positions are often de...

  17. Regioselective Acylation of Diols and Triols: The Cyanide Effect.

    PubMed

    Peng, Peng; Linseis, Michael; Winter, Rainer F; Schmidt, Richard R

    2016-05-11

    Central topics of carbohydrate chemistry embrace structural modifications of carbohydrates and oligosaccharide synthesis. Both require regioselectively protected building blocks that are mainly available via indirect multistep procedures. Hence, direct protection methods targeting a specific hydroxy group are demanded. Dual hydrogen bonding will eventually differentiate between differently positioned hydroxy groups. As cyanide is capable of various kinds of hydrogen bonding and as it is a quite strong sterically nondemanding base, regioselective O-acylations should be possible at low temperatures even at sterically congested positions, thus permitting formation and also isolation of the kinetic product. Indeed, 1,2-cis-diols, having an equatorial and an axial hydroxy group, benzoyl cyanide or acetyl cyanide as an acylating agent, and DMAP as a catalyst yield at -78 °C the thermodynamically unfavorable axial O-acylation product; acyl migration is not observed under these conditions. This phenomenon was substantiated with 3,4-O-unproteced galacto- and fucopyranosides and 2,3-O-unprotected mannopyranosides. Even for 3,4,6-O-unprotected galactopyranosides as triols, axial 4-O-acylation is appreciably faster than O-acylation of the primary 6-hydroxy group. The importance of hydrogen bonding for this unusual regioselectivity could be confirmed by NMR studies and DFT calculations, which indicate favorable hydrogen bonding of cyanide to the most acidic axial hydroxy group supported by hydrogen bonding of the equatorial hydroxy group to the axial oxygen. Thus, the "cyanide effect" is due to dual hydrogen bonding of the axial hydroxy group which enhances the nucleophilicity of the respective oxygen atom, permitting an even faster reaction for diols than for mono-ols. In contrast, fluoride as a counterion favors dual hydrogen bonding to both hydroxy groups leading to equatorial O-acylation. PMID:27104625

  18. Site-specific S-Acylation of Influenza Virus Hemagglutinin

    PubMed Central

    Brett, Katharina; Kordyukova, Larisa V.; Serebryakova, Marina V.; Mintaev, Ramil R.; Alexeevski, Andrei V.; Veit, Michael

    2014-01-01

    S-Acylation of hemagglutinin (HA), the main glycoprotein of influenza viruses, is an essential modification required for virus replication. Using mass spectrometry, we have previously demonstrated specific attachment of acyl chains to individual acylation sites. Whereas the two cysteines in the cytoplasmic tail of HA contain only palmitate, stearate is exclusively attached to a cysteine positioned at the end of the transmembrane region (TMR). Here we analyzed recombinant viruses containing HA with exchange of conserved amino acids adjacent to acylation sites or with a TMR cysteine shifted to a cytoplasmic location to identify the molecular signal that determines preferential attachment of stearate. We first developed a new protocol for sample preparation that requires less material and might thus also be suitable to analyze cellular proteins. We observed cell type-specific differences in the fatty acid pattern of HA: more stearate was attached if human viruses were grown in mammalian compared with avian cells. No underacylated peptides were detected in the mass spectra, and even mutations that prevented generation of infectious virus particles did not abolish acylation of expressed HA as demonstrated by metabolic labeling experiments with [3H]palmitate. Exchange of conserved amino acids in the vicinity of an acylation site had a moderate effect on the stearate content. In contrast, shifting the TMR cysteine to a cytoplasmic location virtually eliminated attachment of stearate. Thus, the location of an acylation site relative to the transmembrane span is the main signal for stearate attachment, but the sequence context and the cell type modulate the fatty acid pattern. PMID:25349209

  19. A new ultra-high pressure liquid chromatography method for the determination of antioxidant flavonol aglycones in six Lysimachia species.

    PubMed

    Tóth, Anita; Végh, Krisztina; Alberti, Ágnes; Béni, Szabolcs; Kéry, Ágnes

    2016-10-01

    UPLC-DAD method was developed and validated for the quantitative determination of free flavonol aglycones (kaempferol, quercetin and myricetin) after acidic hydrolysis in six Lysimachia species. Quantitative analyses showed that the amounts of various flavonol aglycones were significantly different in Lysimachia vulgaris, Lysimachia nummularia, Lysimachia punctata, Lysimachia christinae, Lysimachia ciliata and Lysimachia clethroides. The L. clethroides sample was found to be the richest in kaempferol (25.77 ± 1.29 μg/mg extract) and quercetin (97.67 ± 4.61 μg/mg extract), while the L. nummularia sample contained the highest amount of myricetin (20.79 ± 1.00 μg/mg extract). The antioxidant capacity of hydrolysed extracts was evaluated using in vitro DPPH(•) (2,2-diphenyl-1-picrylhydrazyl) and ABTS(•+) [2,2'-azino-bis-(3-ethylbenzothiazoline-6-sulphonic acid)] decolourisation tests. The observed radical scavenging capacities of the extracts showed a relationship with the measured flavonol aglycone content and composition. The acidic treatment resulted in an increased free radical scavenging activity compared to the untreated methanol extract.

  20. Iridoid glycosides from Harpagophytum procumbens D.C. (devil's claw).

    PubMed

    Qi, Jin; Chen, Ji-Jun; Cheng, Zhi-Hong; Zhou, Jia-Hong; Yu, Bo-Yang; Qiu, Samuel X

    2006-07-01

    Iridoid glycosides, harprocumbide A (6''-O-alpha-D-galactopyranosylharpagoside, 1) and harprocumbide B (6''-O-(cis-p-coumaroyl)-procumbide, 2) were isolated from the tubers of Harpagophytum prucumbens D.C., along with nine known iridoid glycosides 6-O-alpha-D-galactopyranosylharpagoside (3), and harpagoside (4), harpagide (5), 8-cinnamoylmyoporoside (6), 8-O-feruloylhapagide (7), procumbide (8), 6''-O-(p-coumaroyl)-procumbide (9), 8-O-(p-coumaroyl)-harpagide (10) and 8-O-(cis-p-coumaroyl)-harpagide (11). Compound 10 showed marginal inhibition activity against macrophages respiratory burst. PMID:16857222

  1. A glycoside of Nicotina tabacum affects mouse dopaminergic behavior.

    PubMed

    Masuda, Y; Ohnuma, S; Kawagoe, M; Sugiyama, T

    2003-01-01

    Climbing in the forced swimming test is considered a dopaminergic-specific behavior. A substance of Nicotina tabacum affecting dopamine neuronal activity was investigated using the mouse behavioral system. The substance was found to be a glycoside with the peripheral sugar chain structures Fuc alpha 1-2Gal, Gal beta 1-4GlcNAc and GalNAc alpha 1-3GalNAc and with basic polymannoses. The glycoside dose-dependently increased behavior via D2 neuronal activity, but not D1 activity. This suggests that smoking can affect human brain function not only via the nicotinic cholinergic neuron, but also via the D2 neuron.

  2. Synthesis and Photochromic Properties of Configurationally Varied Azobenzene Glycosides

    PubMed Central

    Chandrasekaran, Vijayanand; Johannes, Eugen; Kobarg, Hauke; Sönnichsen, Frank D; Lindhorst, Thisbe K

    2014-01-01

    Spatial orientation of carbohydrates is a meaningful parameter in carbohydrate recognition processes. To vary orientation of sugars with temporal and spatial resolution, photosensitive glycoconjugates with favorable photochromic properties appear to be opportune. Here, a series of azobenzene glycosides were synthesized, employing glycoside synthesis and Mills reaction, to allow “switching” of carbohydrate orientation by reversible E/Z isomerization of the azobenzene N=N double bond. Their photochromic properties were tested and effects of azobenzene substitution as well as the effect of anomeric configuration and the orientation of the sugars 2-hydroxy group were evaluated. PMID:25050228

  3. New Sesquiterpene Glycosides from the Leaves of Eriobotrya japonica.

    PubMed

    Zhaoa, Lei; Li, Han; Rena, Bingru; Wub, Hankui; Chen, Jian; Lia, Weilin

    2015-07-01

    One new sesquiterpene glycoside, named nerolidol-3-O-α-L-rhamnopyranosyl-(1 --> 6)-β-D-glucopyranoside (1), along with one novel natural product nerolidol-3-O-α-L-rhamnopyranosyl-(1 --> 2)-[α-L-rhamnopyranosyl-(1 --> 6)]-β-D-glucopyranoside (2) and two known sesquiterpene glycosides (3-4), were isolated from the leaves of Eriobotrya japonica (Thunb.) Lindl.. Their structures were elucidated on the basis of 1D, 2D NMR and HR-MS data. The chemotaxonomic significance of this type of constituents was discussed.

  4. Antioxidative glycosides from the leaves of Ligustrum robustum.

    PubMed

    He, Zhen-Dan; Lau, Kit-Man; But, Paul Pui-Hay; Jiang, Ren-Wang; Dong, Hui; Ma, Shuang-Cheng; Fung, Kwok-Pui; Ye, Wen-Cai; Sun, Han-Dong

    2003-06-01

    Phytochemical investigation of the ethanol extract of the leaves of Ligustrum robustum, monitored by a bioassay involving the hemolysis of red blood cells induced by 2,2'-azo-bis(2-amidinopropane) dihydrochloride, led to the isolation of three new glycosides, ligurobustosides M (1), N (2), and O (3), along with 10 known ones, osmanthuside B (4), osmanthuside B6 (5), acteoside (6), ligupurpuroside A (7), ligupurpuroside B (8), ligurobustoside C (9), ligurobustoside E (10), ligurobustoside I (11), cosmosiin (12), and rhoifolin (13). The structures of the new compounds were elucidated by spectroscopic methods. Seven of the glycosides showed stronger antioxidant effects than the standard, trolox. PMID:12828473

  5. Steroidal glycosides from Reineckia carnea herba and their antitussive activity.

    PubMed

    Han, Na; Chen, Ling Li; Wang, Yao; Xue, Rui; Zou, Li Bo; Liu, Fang; Yin, Jun

    2013-06-01

    Two new steroidal glycosides, 1α,3α-dihydroxy-5β-pregn-16-en-20-one 3-O-α-L-rhamnopyranoside (1) and 1β,3β,27-trihydroxycholest-16-en-22-one 1,3-di-O-α-L-rhamnoside (2), along with seven known steroidal glycosides (3-9), were isolated from Reineckia carnea herba. Their structures were determined by detailed analysis of their 1D- and 2D-NMR and MS spectra. Compound 9 was isolated for the first time from the Reineckia genus. Except for 8, compounds 2, 3, 4, 5, 6, 7, and 9 displayed clear in vitro antitussive activity.

  6. NMR Tube Degradation Method for Sugar Analysis of Glycosides.

    PubMed

    Giner, José-Luis; Feng, Ju; Kiemle, David J

    2016-09-23

    The sugar subunits of natural glycosides can be conveniently determined by acid hydrolysis and (1)H NMR spectroscopy without isolation or derivatization. The chemical shifts, coupling constants, and integral ratios of the anomeric signals allow each monosaccharide to be identified and its molar ratio to other monosaccharides to be quantified. The NMR data for the anomeric signals of 28 monosaccharides and three disaccharides are reported. Application of the method is demonstrated with the flavonoid glycoside naringin (1), the aminoglycoside antibiotics kanamycin (2) and tobramycin (3), and the saponin digitonin (4). PMID:27603739

  7. Chemical and biological properties of quinochalcone C-glycosides from the florets of Carthamus tinctorius.

    PubMed

    Yue, Shijun; Tang, Yuping; Li, Shujiao; Duan, Jin-Ao

    2013-12-10

    Quinochalcone C-glycosides are regarded as characteristic components that have only been isolated from the florets of Carthamus tinctorius. Recently, quinochalcone C-glycosides were found to have multiple pharmacological activities, which has attracted the attention of many researchers to explore these compounds. This review aims to summarize quinochalcone C-glycosides' physicochemical properties, chromatographic behavior, spectroscopic characteristics, as well as their biological activities, which will be helpful for further study and development of quinochalcone C-glycosides.

  8. Head-group acylation of monogalactosyldiacylglycerol is a common stress response, but the acyl-galactose acyl composition varies with the plant species and applied stress

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Head group acylation of monogalactosyldiacylglycerol is a plant lipid modification occurring during bacterial infection. Little is known about the range of stresses that induce this lipid modification, the molecular species induced, and the function of the modification. Lipidomic analysis using trip...

  9. Analytical methods for monoterpene glycosides in grape and wine. II. Qualitative and quantitative determination of monoterpene glycosides in grape.

    PubMed

    Voirin, S G; Baumes, R L; Sapis, J C; Bayonove, C L

    1992-03-20

    Free and glycosidically bound terpenes of five Vitis vinifera grape cultivars (muscat of Alexandria, muscat of Frontignan, muscat of Hamburg, muscat Ottonel and Gewürztraminer) were investigated. The free and bound fractions were separated by selective retention on Amberlite XAD-2 resin. The glycosidic fractions were analysed by gas chromatography and gas chromatography-mass spectrometry using either enzymic hydrolysis and subsequent analysis of the released aglycones or trimethylsilyl (TMS) and trifluoroacetyl derivatives. The known monoterpenyl, benzyl and 2-phenylethyl beta-D-glucopyranosides, beta-rutinosides, 6-O-alpha-L-arabinofuranosyl-beta-D-glucopyranosides and 6-O-beta-D-apiofuranosyl-beta-D-glucopyranosides were determined. A number of other glycosides were detected and the structures of some of them, mainly apiosylglucosides and glucosides with aglycones in higher oxidation state than linalol, were tentatively identified using the mass spectra of their TMS and TFA derivatives and the results obtained from the analysis of their aglycones. PMID:1577909

  10. Steviol glycosides in purified stevia leaf extract sharing the same metabolic fate.

    PubMed

    Purkayastha, Sidd; Markosyan, Avetik; Prakash, Indra; Bhusari, Sachin; Pugh, George; Lynch, Barry; Roberts, Ashley

    2016-06-01

    The safety of steviol glycosides is based on data available on several individual steviol glycosides and on the terminal absorbed metabolite, steviol. Many more steviol glycosides have been identified, but are not yet included in regulatory assessments. Demonstration that these glycosides share the same metabolic fate would indicate applicability of the same regulatory paradigm. In vitro incubation assays with pooled human fecal homogenates, using rebaudiosides A, B, C, D, E, F and M, as well as steviolbioside and dulcoside A, at two concentrations over 24-48 h, were conducted to assess the metabolic fate of various steviol glycoside classes and to demonstrate that likely all steviol glycosides are metabolized to steviol. The data show that glycosidic side chains containing glucose, rhamnose, xylose, fructose and deoxy-glucose, including combinations of α(1-2), β-1, β(1-2), β(1-3), and β(1-6) linkages, were degraded to steviol mostly within 24 h. Given a common metabolite structure and a shared metabolic fate, safety data available for individual steviol glycosides can be used to support safety of purified steviol glycosides in general. Therefore, steviol glycosides specifications adopted by the regulatory authorities should include all steviol glycosides belonging to the five groups of steviol glycosides and a group acceptable daily intake established. PMID:26924787

  11. Genetically engineered flavonol enriched tomato fruit modulates chondrogenesis to increase bone length in growing animals.

    PubMed

    Choudhary, Dharmendra; Pandey, Ashutosh; Adhikary, Sulekha; Ahmad, Naseer; Bhatia, Chitra; Bhambhani, Sweta; Trivedi, Prabodh Kumar; Trivedi, Ritu

    2016-01-01

    Externally visible body and longitudinal bone growth is a result of proliferation of chondrocytes. In growth disorder, there is delay in the age associated increase in height. The present study evaluates the effect of extract from transgenic tomato fruit expressing AtMYB12 transcription factor on bone health including longitudinal growth. Constitutive expression of AtMYB12 in tomato led to a significantly enhanced biosynthesis of flavonoids in general and the flavonol biosynthesis in particular. Pre-pubertal ovary intact BALB/c mice received daily oral administration of vehicle and ethanolic extract of wild type (WT-TOM) and transgenic AtMYB12-tomato (MYB12-TOM) fruits for six weeks. Animal fed with MYB12-TOM showed no inflammation in hepatic tissues and normal sinusoidal Kupffer cell morphology. MYB12-TOM extract significantly increased tibial and femoral growth and subsequently improved the bone length as compared to vehicle and WT-TOM. Histomorphometry exhibited significantly wider distal femoral and proximal tibial growth plate, increased number and size of hypertrophic chondrocytes in MYB12-TOM which corroborated with micro-CT and expression of BMP-2 and COL-10, marker genes for hypertrophic cells. We conclude that metabolic reprogramming of tomato by AtMYB12 has the potential to improve longitudinal bone growth thus helping in achievement of greater peak bone mass during adolescence. PMID:26917158

  12. New Flavonol Glucuronides from the Flower Buds of Syzygium aromaticum (Clove).

    PubMed

    Ryu, Byeol; Kim, Hye Mi; Lee, Jin Su; Lee, Chan Kyu; Sezirahiga, Jurdas; Woo, Jeong-Hwa; Choi, Jung-Hye; Jang, Dae Sik

    2016-04-20

    Repeated chromatography of the EtOAc-soluble fraction from the 70% EtOH extract of the flower buds of Syzygium aromaticum (clove) led to the isolation and characterization of four new flavonol glucuronides, rhamnetin-3-O-β-d-glucuronide (1), rhamnazin-3-O-β-d-glucuronide (2), rhamnazin-3-O-β-d-glucuronide-6″-methyl ester (3), and rhamnocitrin-3-O-β-d-glucuronide-6″-methyl ester (4), together with 15 flavonoids (5-19) having previously known chemical structures. The structures of the new compounds 1-4 were determined by interpretation of spectroscopic data, particularly by 1D- and 2D-NMR studies. Six flavonoids (6, 7, 9, 14, 18, and 19) were isolated from the flower buds of S. aromaticum for the first time in this study. The flavonoids were examined for their cytotoxicity against human ovarian cancer cells (A2780) using MTT assays. Among the isolates, pachypodol (19) showed the most potent cytotoxicity on A2780 cells with an IC50 value of 8.02 μM. PMID:27045836

  13. Genetically engineered flavonol enriched tomato fruit modulates chondrogenesis to increase bone length in growing animals

    PubMed Central

    Choudhary, Dharmendra; Pandey, Ashutosh; Adhikary, Sulekha; Ahmad, Naseer; Bhatia, Chitra; Bhambhani, Sweta; Trivedi, Prabodh Kumar; Trivedi, Ritu

    2016-01-01

    Externally visible body and longitudinal bone growth is a result of proliferation of chondrocytes. In growth disorder, there is delay in the age associated increase in height. The present study evaluates the effect of extract from transgenic tomato fruit expressing AtMYB12 transcription factor on bone health including longitudinal growth. Constitutive expression of AtMYB12 in tomato led to a significantly enhanced biosynthesis of flavonoids in general and the flavonol biosynthesis in particular. Pre-pubertal ovary intact BALB/c mice received daily oral administration of vehicle and ethanolic extract of wild type (WT-TOM) and transgenic AtMYB12-tomato (MYB12-TOM) fruits for six weeks. Animal fed with MYB12-TOM showed no inflammation in hepatic tissues and normal sinusoidal Kupffer cell morphology. MYB12-TOM extract significantly increased tibial and femoral growth and subsequently improved the bone length as compared to vehicle and WT-TOM. Histomorphometry exhibited significantly wider distal femoral and proximal tibial growth plate, increased number and size of hypertrophic chondrocytes in MYB12-TOM which corroborated with micro-CT and expression of BMP-2 and COL-10, marker genes for hypertrophic cells. We conclude that metabolic reprogramming of tomato by AtMYB12 has the potential to improve longitudinal bone growth thus helping in achievement of greater peak bone mass during adolescence. PMID:26917158

  14. New Flavonol Glucuronides from the Flower Buds of Syzygium aromaticum (Clove).

    PubMed

    Ryu, Byeol; Kim, Hye Mi; Lee, Jin Su; Lee, Chan Kyu; Sezirahiga, Jurdas; Woo, Jeong-Hwa; Choi, Jung-Hye; Jang, Dae Sik

    2016-04-20

    Repeated chromatography of the EtOAc-soluble fraction from the 70% EtOH extract of the flower buds of Syzygium aromaticum (clove) led to the isolation and characterization of four new flavonol glucuronides, rhamnetin-3-O-β-d-glucuronide (1), rhamnazin-3-O-β-d-glucuronide (2), rhamnazin-3-O-β-d-glucuronide-6″-methyl ester (3), and rhamnocitrin-3-O-β-d-glucuronide-6″-methyl ester (4), together with 15 flavonoids (5-19) having previously known chemical structures. The structures of the new compounds 1-4 were determined by interpretation of spectroscopic data, particularly by 1D- and 2D-NMR studies. Six flavonoids (6, 7, 9, 14, 18, and 19) were isolated from the flower buds of S. aromaticum for the first time in this study. The flavonoids were examined for their cytotoxicity against human ovarian cancer cells (A2780) using MTT assays. Among the isolates, pachypodol (19) showed the most potent cytotoxicity on A2780 cells with an IC50 value of 8.02 μM.

  15. Mechanism of CYP2C9 inhibition by flavones and flavonols.

    PubMed

    Si, Dayong; Wang, Ying; Zhou, Yi-Han; Guo, Yingjie; Wang, Juan; Zhou, Hui; Li, Ze-Sheng; Fawcett, J Paul

    2009-03-01

    This article describes an in vitro investigation of the inhibition of cytochrome P450 (P450) 2C9 by a series of flavonoids made up of flavones (flavone, 6-hydroxyflavone, 7-hydroxyflavone, chrysin, baicalein, apigenin, luteolin, scutellarein, and wogonin) and flavonols (galangin, fisetin, kaempferol, morin, and quercetin). With the exception of flavone, all flavonoids were shown to inhibit CYP2C9-mediated diclofenac 4'-hydroxylation in the CYP2C9 RECO system, with K(i) value

  16. Crystal structure of a human cyclin-dependent kinase 6 complexwith a flavonol inhibitor, Fisetin

    SciTech Connect

    Lu, Heshu; Chang, Debbie J.; Baratte, Blandine; Meijer, Laurent; Schulze-Gahmen, Ursula

    2005-01-10

    Cyclin-dependent kinases (CDKs) play a central role in cell cycle control, apoptosis, transcription and neuronal functions. They are important targets for the design of drugs with anti-mitotic and/or anti-neurodegenerative effects. CDK4 and CDK6 form a subfamily among the CDKs in mammalian cells, as defined by sequence similarities. Compared to CDK2 and CDK5, structural information on CDK4 and CDK6 is sparse. We describe here the crystal structure of human CDK6 in complex with a viral cyclin and a flavonol inhibitor, fisetin. Fisetin binds to the active form of CDK6, forming hydrogen bonds with the side chains of residues in the binding pocket that undergo large conformational changes during CDK activation by cyclin binding. The 4-keto group and the 3-hydroxyl group of fisetin are hydrogen bonded with the backbone in the hinge region between the N-terminal and C-terminal kinase domain, as has been observed for many CDK inhibitors. However, CDK2 and HCK kinase in complex with other flavone inhibitors such as quercetin and flavopiridol showed a different binding mode with the inhibitor rotated by about 180. The structural information of the CDK6-fisetin complex is correlated with the binding affinities of different flavone inhibitors for CDK6. This complex structure is the first description of an inhibitor complex with a kinase from the CDK4/6 subfamily and can provide a basis for selecting and designing inhibitor compounds with higher affinity and specificity.

  17. Fisetin, a bioactive flavonol, attenuates allergic airway inflammation through negative regulation of NF-κB.

    PubMed

    Goh, Fera Y; Upton, Nadine; Guan, Shouping; Cheng, Chang; Shanmugam, Muthu K; Sethi, Gautam; Leung, Bernard P; Wong, W S Fred

    2012-03-15

    Persistent activation of nuclear factor-κB (NF-κB) has been associated with the development of asthma. Fisetin (3,7,3',4'-tetrahydroxyflavone), a naturally occurring bioactive flavonol, has been shown to inhibit NF-κB activity. We hypothesized that fisetin may attenuate allergic asthma via negative regulation of the NF-κB activity. Female BALB/c mice sensitized and challenged with ovalbumin developed airway inflammation. Bronchoalveolar lavage fluid was assessed for total and differential cell counts, and cytokine and chemokine levels. Lung tissues were examined for cell infiltration and mucus hypersecretion, and the expression of inflammatory biomarkers. Airway hyperresponsiveness was monitored by direct airway resistance analysis. Fisetin dose-dependently inhibited ovalbumin-induced increases in total cell count, eosinophil count, and IL-4, IL-5 and IL-13 levels recovered in bronchoalveolar lavage fluid. It attenuated ovalbumin-induced lung tissue eosinophilia and airway mucus production, mRNA expression of adhesion molecules, chitinase, IL-17, IL-33, Muc5ac and inducible nitric oxide synthase in lung tissues, and airway hyperresponsiveness to methacholine. Fisetin blocked NF-κB subunit p65 nuclear translocation and DNA-binding activity in the nuclear extracts from lung tissues of ovalbumin-challenged mice. In normal human bronchial epithelial cells, fisetin repressed TNF-α-induced NF-κB-dependent reporter gene expression. Our findings implicate a potential therapeutic value of fisetin in the treatment of asthma through negative regulation of NF-κB pathway.

  18. Regioselective self-acylating cyclodextrins in organic solvent

    PubMed Central

    Cho, Eunae; Yun, Deokgyu; Jeong, Daham; Im, Jieun; Kim, Hyunki; Dindulkar, Someshwar D.; Choi, Youngjin; Jung, Seunho

    2016-01-01

    Amphiphilic cyclodextrins have been synthesized with self-acylating reaction using vinyl esters in dimethylformamide. In the present study no base, catalyst, or enzyme was used, and the structural analyses using thin layer chromatography, nuclear magnetic resonance spectroscopy and mass spectrometry show that the cyclodextrin is substituted preferentially by one acyl moiety at the C2 position of the glucose unit, suggesting that cyclodextrin functions as a regioselective catalytic carbohydrate in organic solvent. In the self-acylation, the most acidic OH group at the 2-position and the inclusion complexing ability of cyclodextrin were considered to be significant. The substrate preference was also observed in favor of the long-chain acyl group, which could be attributed to the inclusion ability of cyclodextrin cavity. Furthermore, using the model amphiphilic building block, 2-O-mono-lauryl β-cyclodextrin, the self-organized supramolecular architecture with nano-vesicular morphology in water was investigated by fluorescence spectroscopy, dynamic light scattering and transmission electron microscopy. The cavity-type nano-assembled vesicle and the novel synthetic methods for the preparation of mono-acylated cyclodextrin should be of great interest with regard to drug/gene delivery systems, functional surfactants, and carbohydrate derivatization methods. PMID:27020946

  19. Regioselective self-acylating cyclodextrins in organic solvent

    NASA Astrophysics Data System (ADS)

    Cho, Eunae; Yun, Deokgyu; Jeong, Daham; Im, Jieun; Kim, Hyunki; Dindulkar, Someshwar D.; Choi, Youngjin; Jung, Seunho

    2016-03-01

    Amphiphilic cyclodextrins have been synthesized with self-acylating reaction using vinyl esters in dimethylformamide. In the present study no base, catalyst, or enzyme was used, and the structural analyses using thin layer chromatography, nuclear magnetic resonance spectroscopy and mass spectrometry show that the cyclodextrin is substituted preferentially by one acyl moiety at the C2 position of the glucose unit, suggesting that cyclodextrin functions as a regioselective catalytic carbohydrate in organic solvent. In the self-acylation, the most acidic OH group at the 2-position and the inclusion complexing ability of cyclodextrin were considered to be significant. The substrate preference was also observed in favor of the long-chain acyl group, which could be attributed to the inclusion ability of cyclodextrin cavity. Furthermore, using the model amphiphilic building block, 2-O-mono-lauryl β-cyclodextrin, the self-organized supramolecular architecture with nano-vesicular morphology in water was investigated by fluorescence spectroscopy, dynamic light scattering and transmission electron microscopy. The cavity-type nano-assembled vesicle and the novel synthetic methods for the preparation of mono-acylated cyclodextrin should be of great interest with regard to drug/gene delivery systems, functional surfactants, and carbohydrate derivatization methods.

  20. Regioselective self-acylating cyclodextrins in organic solvent.

    PubMed

    Cho, Eunae; Yun, Deokgyu; Jeong, Daham; Im, Jieun; Kim, Hyunki; Dindulkar, Someshwar D; Choi, Youngjin; Jung, Seunho

    2016-01-01

    Amphiphilic cyclodextrins have been synthesized with self-acylating reaction using vinyl esters in dimethylformamide. In the present study no base, catalyst, or enzyme was used, and the structural analyses using thin layer chromatography, nuclear magnetic resonance spectroscopy and mass spectrometry show that the cyclodextrin is substituted preferentially by one acyl moiety at the C2 position of the glucose unit, suggesting that cyclodextrin functions as a regioselective catalytic carbohydrate in organic solvent. In the self-acylation, the most acidic OH group at the 2-position and the inclusion complexing ability of cyclodextrin were considered to be significant. The substrate preference was also observed in favor of the long-chain acyl group, which could be attributed to the inclusion ability of cyclodextrin cavity. Furthermore, using the model amphiphilic building block, 2-O-mono-lauryl β-cyclodextrin, the self-organized supramolecular architecture with nano-vesicular morphology in water was investigated by fluorescence spectroscopy, dynamic light scattering and transmission electron microscopy. The cavity-type nano-assembled vesicle and the novel synthetic methods for the preparation of mono-acylated cyclodextrin should be of great interest with regard to drug/gene delivery systems, functional surfactants, and carbohydrate derivatization methods. PMID:27020946

  1. Two fatty acyl reductases involved in moth pheromone biosynthesis

    PubMed Central

    Antony, Binu; Ding, Bao-Jian; Moto, Ken’Ichi; Aldosari, Saleh A.; Aldawood, Abdulrahman S.

    2016-01-01

    Fatty acyl reductases (FARs) constitute an evolutionarily conserved gene family found in all kingdoms of life. Members of the FAR gene family play diverse roles, including seed oil synthesis, insect pheromone biosynthesis, and mammalian wax biosynthesis. In insects, FAR genes dedicated to sex pheromone biosynthesis (pheromone-gland-specific fatty acyl reductase, pgFAR) form a unique clade that exhibits substantial modifications in gene structure and possesses unique specificity and selectivity for fatty acyl substrates. Highly selective and semi-selective ‘single pgFARs’ produce single and multicomponent pheromone signals in bombycid, pyralid, yponomeutid and noctuid moths. An intriguing question is how a ‘single reductase’ can direct the synthesis of several fatty alcohols of various chain lengths and isomeric forms. Here, we report two active pgFARs in the pheromone gland of Spodoptera, namely a semi-selective, C14:acyl-specific pgFAR and a highly selective, C16:acyl-specific pgFAR, and demonstrate that these pgFARs play a pivotal role in the formation of species-specific signals, a finding that is strongly supported by functional gene expression data. The study envisages a new area of research for disclosing evolutionary changes associated with C14- and C16-specific FARs in moth pheromone biosynthesis. PMID:27427355

  2. Two fatty acyl reductases involved in moth pheromone biosynthesis.

    PubMed

    Antony, Binu; Ding, Bao-Jian; Moto, Ken'Ichi; Aldosari, Saleh A; Aldawood, Abdulrahman S

    2016-01-01

    Fatty acyl reductases (FARs) constitute an evolutionarily conserved gene family found in all kingdoms of life. Members of the FAR gene family play diverse roles, including seed oil synthesis, insect pheromone biosynthesis, and mammalian wax biosynthesis. In insects, FAR genes dedicated to sex pheromone biosynthesis (pheromone-gland-specific fatty acyl reductase, pgFAR) form a unique clade that exhibits substantial modifications in gene structure and possesses unique specificity and selectivity for fatty acyl substrates. Highly selective and semi-selective 'single pgFARs' produce single and multicomponent pheromone signals in bombycid, pyralid, yponomeutid and noctuid moths. An intriguing question is how a 'single reductase' can direct the synthesis of several fatty alcohols of various chain lengths and isomeric forms. Here, we report two active pgFARs in the pheromone gland of Spodoptera, namely a semi-selective, C14:acyl-specific pgFAR and a highly selective, C16:acyl-specific pgFAR, and demonstrate that these pgFARs play a pivotal role in the formation of species-specific signals, a finding that is strongly supported by functional gene expression data. The study envisages a new area of research for disclosing evolutionary changes associated with C14- and C16-specific FARs in moth pheromone biosynthesis. PMID:27427355

  3. Mammalian acyl-CoA:lysophosphatidylcholine acyltransferase enzymes.

    PubMed

    Soupene, Eric; Fyrst, Henrik; Kuypers, Frans A

    2008-01-01

    The mammalian RBC lacks de novo lipid synthesis but maintains its membrane composition by rapid turnover of acyl moieties at the sn-2 position of phospholipids. Plasma-derived fatty acids are esterified to acyl-CoA by acyl-CoA synthetases and transferred to lysophospholipids by acyl-CoA:lysophospholipid acyltransferases. We report the characterization of three lysophosphatidylcholine (lysoPC) acyltransferases (LPCATs), products of the AYTL1, -2, and -3 genes. These proteins are three members of a LPCAT family, of which all three genes are expressed in an erythroleukemic cell line. Aytl2 mRNA was detected in mouse reticulocytes, and the presence of the product of the human ortholog was confirmed in adult human RBCs. The three murine Aytl proteins generated phosphatidylcholine from long-chain acyl-CoA and lysoPC when expressed in Escherichia coli membranes. Spliced variants of Aytl1, affecting a conserved catalytic motif, were identified. Calcium and magnesium modulated LPCAT activity of both Aytl1 and -2 proteins that exhibit EF-hand motifs at the C terminus. Characterization of the product of the Aytl2 gene as the phosphatidylcholine reacylating enzyme in RBCs represents the identification of a plasma membrane lysophospholipid acyltransferase and establishes the function of a LPCAT protein.

  4. Morinlongosides A-C, Two New Naphthalene Glycoside and a New Iridoid Glycoside from the Roots of Morinda longissima.

    PubMed

    Cuong, Nguyen Manh; Huong, Tran Thu; Son, Ninh The; Cuong, To Dao; Van, Doan Thi; Khanh, Pham Ngoc; Ha, Vu Thi; Tram, Nguyen Cong Thuy; Long, Pham Quoc; Kim, Young Ho

    2016-01-01

    Two new naphthalene glycosides, morinlongosides A and B (1, 2) and a new iridoid glycoside, morinlongoside C (3), together with four known ones, geniposidic acid (4), (3R)-3-O-[β-D-xylopyranosyl-(1→6)-β-D-glucopyranosyl]-l-octen-3-ol (5), lucidin-3-O-β-primeveroside (6), and morindone-6-O-β-gentiobioside (7), were isolated from the roots of Morinda longissima Y. Z. RUAN. The structures of all isolated compounds (1-7) were elucidated on the basis of spectroscopic data (high resolution (HR)-MS, one and two dimensional (1/2D)-NMR). PMID:27477665

  5. Bioactive saponins and glycosides. XXVII. Structures of new cucurbitane-type triterpene glycosides and antiallergic constituents from Citrullus colocynthis.

    PubMed

    Yoshikawa, Masayuki; Morikawa, Toshio; Kobayashi, Hisanori; Nakamura, Akihiko; Matsuhira, Koudai; Nakamura, Seikou; Matsuda, Hisashi

    2007-03-01

    The methanolic extract from the fruit of Citrullus colocynthis showed an inhibitory effect on ear passive cutaneous anaphylaxis reactions as a type I allergic model in mice. From the methanolic extract, two new cucurbitane-type triterpene glycosides, colocynthosides A and B, were isolated together with 17 known constituents. The structures of colocynthosides A and B were elucidated on the basis of chemical and physicochemical evidence. In addition, the principal cucurbitane-type triterpene glycoside, cucurbitacin E 2-O-beta-D-glucopyranoside, and its aglycon, cucurbitacin E, exhibited the antiallergic activity at a dose of 100 and 1.25 mg/kg, p.o., respectively.

  6. Phenolic profiling of an extract from Eugenia jambos L. (Alston)--the structure of three flavonoid glycosides--antioxidant and cytotoxic activities.

    PubMed

    Nawwar, M A; Hashem, A N; Hussein, S A; Swilam, N F; Becker, A; Haertel, B; Lindequist, U; El-Khatib, A; Linscheid, M W

    2016-03-01

    Phenolic metabolite profiling and identification using high performance liquid chromatography (HPLC) coupled to high resolution accurate mass spectrometry (HR-ESI-MS) with detection of negative ions was used for assaying the complex mixture of phenolics of an aqueous ethanol leaf extract of Eugeniajambos L. (Myrtaceae). Eight known polyphenolics were tentatively identified, and, in addition, three hitherto unknown flavonol-O-glycosides were detected in the extract. These unknowns were taken as the targets and isolated by means of consecutive polyamide S6, MCI gel and repeated Sephadex LH-20 column fractionation. The isolation and purification were monitored by HPLC/ESI-MS. The isolates were subsequently identified as quercetin 3-O-xylosyl-(1"' --> 2")-O-xyloside, myricetin 7-methylether 3-O-xylosyl-(1"' --> 2")-rhamnoside and myricetin 3',5'-dimethyl ether 3-O-xylosyl-(1"'-->* 2")-O-rhamnoside. All known metabolites were also separated by applying the same chromatographic techniques. ESI-MS, ¹H and ¹³C NMR spectra were then recorded, completely interpreted and confirmed by HR-ESI-MS and 2D NMR spectroscopy. In order to get information about biological activities of E. jambos the extract was tested for radical scavenging activity by DPPH and ORAC assay. In addition, its cytotoxicity was assessed by the neutral red assay against non-tumorigenic HaCaT keratinocytes and the human bladder carcinoma cell line 5637.

  7. Phenolic profiling of an extract from Eugenia jambos L. (Alston)--the structure of three flavonoid glycosides--antioxidant and cytotoxic activities.

    PubMed

    Nawwar, M A; Hashem, A N; Hussein, S A; Swilam, N F; Becker, A; Haertel, B; Lindequist, U; El-Khatib, A; Linscheid, M W

    2016-03-01

    Phenolic metabolite profiling and identification using high performance liquid chromatography (HPLC) coupled to high resolution accurate mass spectrometry (HR-ESI-MS) with detection of negative ions was used for assaying the complex mixture of phenolics of an aqueous ethanol leaf extract of Eugeniajambos L. (Myrtaceae). Eight known polyphenolics were tentatively identified, and, in addition, three hitherto unknown flavonol-O-glycosides were detected in the extract. These unknowns were taken as the targets and isolated by means of consecutive polyamide S6, MCI gel and repeated Sephadex LH-20 column fractionation. The isolation and purification were monitored by HPLC/ESI-MS. The isolates were subsequently identified as quercetin 3-O-xylosyl-(1"' --> 2")-O-xyloside, myricetin 7-methylether 3-O-xylosyl-(1"' --> 2")-rhamnoside and myricetin 3',5'-dimethyl ether 3-O-xylosyl-(1"'-->* 2")-O-rhamnoside. All known metabolites were also separated by applying the same chromatographic techniques. ESI-MS, ¹H and ¹³C NMR spectra were then recorded, completely interpreted and confirmed by HR-ESI-MS and 2D NMR spectroscopy. In order to get information about biological activities of E. jambos the extract was tested for radical scavenging activity by DPPH and ORAC assay. In addition, its cytotoxicity was assessed by the neutral red assay against non-tumorigenic HaCaT keratinocytes and the human bladder carcinoma cell line 5637. PMID:27183713

  8. Remote control of regioselectivity in acyl-acyl carrier protein-desaturases

    PubMed Central

    Guy, Jodie E.; Whittle, Edward; Moche, Martin; Lengqvist, Johan; Lindqvist, Ylva; Shanklin, John

    2011-01-01

    Regiospecific desaturation of long-chain saturated fatty acids has been described as approaching the limits of the discriminatory power of enzymes because the substrate entirely lacks distinguishing features close to the site of dehydrogenation. To identify the elusive mechanism underlying regioselectivity, we have determined two crystal structures of the archetypal Δ9 desaturase from castor in complex with acyl carrier protein (ACP), which show the bound ACP ideally situated to position C9 and C10 of the acyl chain adjacent to the diiron active site for Δ9 desaturation. Analysis of the structures and modeling of the complex between the highly homologous ivy Δ4 desaturase and ACP, identified a residue located at the entrance to the binding cavity, Asp280 in the castor desaturase (Lys275 in the ivy desaturase), which is strictly conserved within Δ9 and Δ4 enzymes but differs between them. We hypothesized that interaction between Lys275 and the phosphate of the pantetheine, seen in the ivy model, is key to positioning C4 and C5 adjacent to the diiron center for Δ4 desaturation. Mutating castor Asp280 to Lys resulted in a major shift from Δ9 to Δ4 desaturation. Thus, interaction between desaturase side-chain 280 and phospho-serine 38 of ACP, approximately 27 Å from the site of double-bond formation, predisposes ACP binding that favors either Δ9 or Δ4 desaturation via repulsion (acidic side chain) or attraction (positively charged side chain), respectively. Understanding the mechanism underlying remote control of regioselectivity provides the foundation for reengineering desaturase enzymes to create designer chemical feedstocks that would provide alternatives to those currently obtained from petrochemicals. PMID:21930947

  9. Remote control of regioselectivity in acyl-acyl carrier protein-desaturases.

    PubMed

    Guy, Jodie E; Whittle, Edward; Moche, Martin; Lengqvist, Johan; Lindqvist, Ylva; Shanklin, John

    2011-10-01

    Regiospecific desaturation of long-chain saturated fatty acids has been described as approaching the limits of the discriminatory power of enzymes because the substrate entirely lacks distinguishing features close to the site of dehydrogenation. To identify the elusive mechanism underlying regioselectivity, we have determined two crystal structures of the archetypal Δ9 desaturase from castor in complex with acyl carrier protein (ACP), which show the bound ACP ideally situated to position C9 and C10 of the acyl chain adjacent to the diiron active site for Δ9 desaturation. Analysis of the structures and modeling of the complex between the highly homologous ivy Δ4 desaturase and ACP, identified a residue located at the entrance to the binding cavity, Asp280 in the castor desaturase (Lys275 in the ivy desaturase), which is strictly conserved within Δ9 and Δ4 enzymes but differs between them. We hypothesized that interaction between Lys275 and the phosphate of the pantetheine, seen in the ivy model, is key to positioning C4 and C5 adjacent to the diiron center for Δ4 desaturation. Mutating castor Asp280 to Lys resulted in a major shift from Δ9 to Δ4 desaturation. Thus, interaction between desaturase side-chain 280 and phospho-serine 38 of ACP, approximately 27 Å from the site of double-bond formation, predisposes ACP binding that favors either Δ9 or Δ4 desaturation via repulsion (acidic side chain) or attraction (positively charged side chain), respectively. Understanding the mechanism underlying remote control of regioselectivity provides the foundation for reengineering desaturase enzymes to create designer chemical feedstocks that would provide alternatives to those currently obtained from petrochemicals. PMID:21930947

  10. Two new non-glycosidic iridoids from Sambucus ebulus.

    PubMed

    Tomassini, Lamberto; Foddai, Sebastiano; Ventrone, Antonio; Nicoletti, Marcello

    2013-01-01

    Two new 'Valeriana-type' non-glycosidic iridoids were isolated from the aerial parts (leaves and young branches) of Sambucus ebulus L., a perennial herbaceous species widespread in Europe. The structures were elucidated, by spectroscopic means, as 7-O-acetylpatrinoside aglycone (1) and 10-O-acetylpatrinoside aglycone (2).

  11. New glycosides of acetophenone derivatives and phenylpropanoids from Juniperus occidentalis.

    PubMed

    Inatomi, Yuka; Murata, Hiroko; Inada, Akira; Nakanishi, Tsutomu; Lang, Frank A; Murata, Jin; Iinuma, Munekazu

    2013-04-01

    New glycosides of seven acetophenone derivatives (1-7) and two phenylpropanoids (8, 9), named juniperosides III-XI, have been isolated from the MeOH extract of the leaves and stems of Juniperus occidentalis Hook. (Cupressaceae), together with eleven other known compounds. The structures of these compounds have been successfully elucidated using a variety of spectroscopic techniques.

  12. Marruboside, a new phenylethanoid glycoside from Marrubium vulgare L.

    PubMed

    Sahpaz, Sevser; Hennebelle, Thierry; Bailleul, François

    2002-06-01

    A new phenylethanoid glycoside, marruboside, has been isolated from the aerial parts of Marrubium vulgare L. Its structure was established as 3,4-dihydroxy-beta-phenylethoxy-O-[beta-D-apiofuranosyl-(1-->2)-alpha-L-rhamnopyranosyl-(1-->3)]-[beta-D-apiofuranosyl-(1-->6)]-4-O-caffeoyl-beta-D-glucopyranoside, on the basis of spectroscopic evidence.

  13. Triterpenoid glycosides from the leaves of Meliosma henryi.

    PubMed

    Alabdul Magid, Abdulmagid; Morjani, Hamid; Harakat, Dominique; Madoulet, Claudie; Dumontet, Vincent; Lavaud, Catherine

    2015-01-01

    Seven triterpenoid glycosides, named meliosmosides A-G, were isolated from the leaves of Meliosma henryi Diels (Sabiaceae). Their structures were elucidated by different spectroscopic methods including 1D and 2D NMR experiments as well as HRESIMS analysis. Isolated compounds were evaluated for their cytotoxic activity against KB cell line. PMID:25468712

  14. Glycosidation of Methanol with Ribose: An Interdisciplinary Undergraduate Laboratory Experiment

    ERIC Educational Resources Information Center

    Simon, Erin; Cook, Katie; Pritchard, Meredith R.; Stripe, Wayne; Bruch, Martha; Bendinskas, Kestutis

    2010-01-01

    This exercise provides students hands-on experience with the topics of glycosidation, hemiacetal and acetal formation, proton nuclear magnetic resonance ([superscript 1]H NMR) spectroscopy, and kinetic and thermodynamic product formation. In this laboratory experiment, the methyl acetal of ribose is synthesized, and the kinetic and thermodynamic…

  15. Three new hecogenin glycosides from fermented leaves of Agave americana.

    PubMed

    Jin, Jian-Ming; Liu, Xi-Kui; Yang, Chong-Ren

    2003-06-01

    Eight steroidal compounds, including three new hecogenin glycosides, agamenosides D-F, were isolated from the fermented leaves of Agave americana. The structures of the new steroidal saponins were elucidated by spectroscopic data and chemical methods. The activity of the isolated compounds on deformations of mycelia germinated from conidia of Pyricularia oaryzae P-2b was evaluated.

  16. Identification of Unusual Phospholipid Fatty Acyl Compositions of Acanthamoeba castellanii

    PubMed Central

    Palusinska-Szysz, Marta; Kania, Magdalena; Turska-Szewczuk, Anna; Danikiewicz, Witold; Russa, Ryszard; Fuchs, Beate

    2014-01-01

    Acanthamoeba are opportunistic protozoan pathogens that may lead to sight-threatening keratitis and fatal granulomatous encephalitis. The successful prognosis requires early diagnosis and differentiation of pathogenic Acanthamoeba followed by aggressive treatment regimen. The plasma membrane of Acanthamoeba consists of 25% phospholipids (PL). The presence of C20 and, recently reported, 28- and 30-carbon fatty acyl residues is characteristic of amoeba PL. A detailed knowledge about this unusual PL composition could help to differentiate Acanthamoeba from other parasites, e.g. bacteria and develop more efficient treatment strategies. Therefore, the detailed PL composition of Acanthamoeba castellanii was investigated by 31P nuclear magnetic resonance spectroscopy, thin-layer chromatography, gas chromatography, high performance liquid chromatography and liquid chromatography-mass spectrometry. Normal and reversed phase liquid chromatography coupled with mass spectrometric detection was used for detailed characterization of the fatty acyl composition of each detected PL. The most abundant fatty acyl residues in each PL class were octadecanoyl (18∶0), octadecenoyl (18∶1 Δ9) and hexadecanoyl (16∶0). However, some selected PLs contained also very long fatty acyl chains: the presence of 28- and 30-carbon fatty acyl residues was confirmed in phosphatidylethanolamine (PE), phosphatidylserine, phosphatidic acid and cardiolipin. The majority of these fatty acyl residues were also identified in PE that resulted in the following composition: 28∶1/20∶2, 30∶2/18∶1, 28∶0/20∶2, 30∶2/20∶4 and 30∶3/20∶3. The PL of amoebae are significantly different in comparison to other cells: we describe here for the first time unusual, very long chain fatty acids with Δ5-unsaturation (30∶35,21,24) and 30∶221,24 localized exclusively in specific phospholipid classes of A. castellanii protozoa that could serve as specific biomarkers for the presence of these

  17. Quantum chemical study of penicillin: Reactions after acylation

    NASA Astrophysics Data System (ADS)

    Li, Rui; Feng, Dacheng; Zhu, Feng

    The density functional theory methods were used on the model molecules of penicillin to determine the possible reactions after their acylation on ?-lactamase, and the results were compared with sulbactam we have studied. The results show that, the acylated-enzyme tetrahedral intermediate can evolves with opening of ?-lactam ring as well as the thiazole ring; the thiazole ring-open products may be formed via ?-lactam ring-open product or from tetrahedral intermediate directly. Those products, in imine or enamine form, can tautomerize via hydrogen migration. In virtue of the water-assisted, their energy barriers are obviously reduced.

  18. Diverse Activities of Histone Acylations Connect Metabolism to Chromatin Function.

    PubMed

    Dutta, Arnob; Abmayr, Susan M; Workman, Jerry L

    2016-08-18

    Modifications of histones play important roles in balancing transcriptional output. The discovery of acyl marks, besides histone acetylation, has added to the functional diversity of histone modifications. Since all modifications use metabolic intermediates as substrates for chromatin-modifying enzymes, the prevalent landscape of histone modifications in any cell type is a snapshot of its metabolic status. Here, we review some of the current findings of how differential use of histone acylations regulates gene expression as response to metabolic changes and differentiation programs. PMID:27540855

  19. Novel approach in LC-MS/MS using MRM to generate a full profile of acyl-CoAs: discovery of acyl-dephospho-CoAs[S

    PubMed Central

    Li, Qingling; Zhang, Shenghui; Berthiaume, Jessica M.; Simons, Brigitte; Zhang, Guo-Fang

    2014-01-01

    A metabolomic approach to selectively profile all acyl-CoAs was developed using a programmed multiple reaction monitoring (MRM) method in LC-MS/MS and was employed in the analysis of various rat organs. The programmed MRM method possessed 300 mass ion transitions with the mass difference of 507 between precursor ion (Q1) and product ion (Q3), and the precursor ion started from m/z 768 and progressively increased one mass unit at each step. Acyl-dephospho-CoAs resulting from the dephosphorylation of acyl-CoAs were identified by accurate MS and fragmentation. Acyl-dephospho-CoAs were also quantitatively scanned by the MRM method with the mass difference of 427 between Q1 and Q3 mass ions. Acyl-CoAs and dephospho-CoAs were assayed with limits of detection ranging from 2 to 133 nM. The accuracy of the method was demonstrated by assaying a range of concentrations of spiked acyl-CoAs with the results of 80–114%. The distribution of acyl-CoAs reflects the metabolic status of each organ. The physiological role of dephosphorylation of acyl-CoAs remains to be further characterized. The methodology described herein provides a novel strategy in metabolomic studies to quantitatively and qualitatively profile all potential acyl-CoAs and acyl-dephospho-CoAs. PMID:24367045

  20. Chemoenzymatic Synthesis of Acyl Coenzyme A Substrates Enables in Situ Labeling of Small Molecules and Proteins.

    PubMed

    Agarwal, Vinayak; Diethelm, Stefan; Ray, Lauren; Garg, Neha; Awakawa, Takayoshi; Dorrestein, Pieter C; Moore, Bradley S

    2015-09-18

    A chemoenzymatic approach to generate fully functional acyl coenzyme A molecules that are then used as substrates to drive in situ acyl transfer reactions is described. Mass spectrometry based assays to verify the identity of acyl coenzyme A enzymatic products are also illustrated. The approach is responsive to a diverse array of carboxylic acids that can be elaborated to their corresponding coenzyme A thioesters, with potential applications in wide-ranging chemical biology studies that utilize acyl coenzyme A substrates.

  1. Chlamydia trachomatis Scavenges Host Fatty Acids for Phospholipid Synthesis via an Acyl-Acyl Carrier Protein Synthetase*

    PubMed Central

    Yao, Jiangwei; Dodson, V. Joshua; Frank, Matthew W.; Rock, Charles O.

    2015-01-01

    The obligate intracellular parasite Chlamydia trachomatis has a reduced genome but relies on de novo fatty acid and phospholipid biosynthesis to produce its membrane phospholipids. Lipidomic analyses showed that 8% of the phospholipid molecular species synthesized by C. trachomatis contained oleic acid, an abundant host fatty acid that cannot be made by the bacterium. Mass tracing experiments showed that isotopically labeled palmitic, myristic, and lauric acids added to the medium were incorporated into C. trachomatis-derived phospholipid molecular species. HeLa cells did not elongate lauric acid, but infected HeLa cell cultures elongated laurate to myristate and palmitate. The elongated fatty acids were incorporated exclusively into C. trachomatis-produced phospholipid molecular species. C. trachomatis has adjacent genes encoding the separate domains of the bifunctional acyl-acyl carrier protein (ACP) synthetase/2-acylglycerolphosphoethanolamine acyltransferase gene (aas) of Escherichia coli. The CT775 gene encodes an acyltransferase (LpaT) that selectively transfers fatty acids from acyl-ACP to the 1-position of 2-acyl-glycerophospholipids. The CT776 gene encodes an acyl-ACP synthetase (AasC) with a substrate preference for palmitic compared with oleic acid in vitro. Exogenous fatty acids were elongated and incorporated into phospholipids by Escherichia coli-expressing AasC, illustrating its function as an acyl-ACP synthetase in vivo. These data point to an AasC-dependent pathway in C. trachomatis that selectively scavenges host saturated fatty acids to be used for the de novo synthesis of its membrane constituents. PMID:26195634

  2. Chlamydia trachomatis Scavenges Host Fatty Acids for Phospholipid Synthesis via an Acyl-Acyl Carrier Protein Synthetase.

    PubMed

    Yao, Jiangwei; Dodson, V Joshua; Frank, Matthew W; Rock, Charles O

    2015-09-01

    The obligate intracellular parasite Chlamydia trachomatis has a reduced genome but relies on de novo fatty acid and phospholipid biosynthesis to produce its membrane phospholipids. Lipidomic analyses showed that 8% of the phospholipid molecular species synthesized by C. trachomatis contained oleic acid, an abundant host fatty acid that cannot be made by the bacterium. Mass tracing experiments showed that isotopically labeled palmitic, myristic, and lauric acids added to the medium were incorporated into C. trachomatis-derived phospholipid molecular species. HeLa cells did not elongate lauric acid, but infected HeLa cell cultures elongated laurate to myristate and palmitate. The elongated fatty acids were incorporated exclusively into C. trachomatis-produced phospholipid molecular species. C. trachomatis has adjacent genes encoding the separate domains of the bifunctional acyl-acyl carrier protein (ACP) synthetase/2-acylglycerolphosphoethanolamine acyltransferase gene (aas) of Escherichia coli. The CT775 gene encodes an acyltransferase (LpaT) that selectively transfers fatty acids from acyl-ACP to the 1-position of 2-acyl-glycerophospholipids. The CT776 gene encodes an acyl-ACP synthetase (AasC) with a substrate preference for palmitic compared with oleic acid in vitro. Exogenous fatty acids were elongated and incorporated into phospholipids by Escherichia coli-expressing AasC, illustrating its function as an acyl-ACP synthetase in vivo. These data point to an AasC-dependent pathway in C. trachomatis that selectively scavenges host saturated fatty acids to be used for the de novo synthesis of its membrane constituents. PMID:26195634

  3. Potentiation of luteolin cytotoxicity by flavonols fisetin and quercetin in human chronic lymphocytic leukemia cell lines.

    PubMed

    Sak, Katrin; Kasemaa, Kristi; Everaus, Hele

    2016-09-14

    Despite numerous studies chronic lymphocytic leukemia (CLL) still remains an incurable disease. Therefore, all new compounds and novel strategies which are able to eradicate CLL cells should be considered as valuable clues for a potential future remedy against this malignancy. In the present study, the cytotoxic profiles of natural flavonoids were described in two human CLL cell lines, HG-3 and EHEB, indicating the flavone luteolin as the most potent flavonoid with half-maximal inhibitory constants (IC50) of 37 μM and 26 μM, respectively. Luteolin significantly increased the apoptotic cell population in both cell lines by increasing the activities of caspases-3 and -9 and triggering the intrinsic apoptotic pathway. Two flavonols, fisetin and quercetin, were somewhat less efficient in suppressing cellular viability, whereas baicalein, chrysin, (+)-catechin and hesperetin exerted only a small or no response at doses as high as 100 μM. Both fisetin and quercetin were able to augment the cytotoxic activity of luteolin in both cell lines by reducing the IC50 values up to four fold. As a result of this, luteolin displayed cytotoxicity activity already at low micromolar concentrations that could potentially be physiologically achievable through oral ingestion. No other tested flavonoids were capable of sensitizing CLL cells to luteolin pointing to a specific binding of fisetin and quercetin to the cellular targets which interfere with the signaling pathways induced by luteolin. Although further molecular studies to unravel this potentiating mechanism are certainly needed, this phenomenon could contribute to future remedies for prevention and treatment of chronic lymphocytic leukemia.

  4. Flavonol-rich dark cocoa significantly decreases plasma endothelin-1 and improves cognition in urban children.

    PubMed

    Calderón-Garcidueñas, Lilian; Mora-Tiscareño, Antonieta; Franco-Lira, Maricela; Cross, Janet V; Engle, Randall; Aragón-Flores, Mariana; Gómez-Garza, Gilberto; Jewells, Valerie; Medina-Cortina, Humberto; Solorio, Edelmira; Chao, Chih-Kai; Zhu, Hongtu; Mukherjee, Partha S; Ferreira-Azevedo, Lara; Torres-Jardón, Ricardo; D'Angiulli, Amedeo

    2013-01-01

    Air pollution exposures are linked to systemic inflammation, cardiovascular and respiratory morbidity and mortality, neuroinflammation and neuropathology in young urbanites. In particular, most Mexico City Metropolitan Area (MCMA) children exhibit subtle cognitive deficits, and neuropathology studies show 40% of them exhibiting frontal tau hyperphosphorylation and 51% amyloid-β diffuse plaques (compared to 0% in low pollution control children). We assessed whether a short cocoa intervention can be effective in decreasing plasma endothelin 1 (ET-1) and/or inflammatory mediators in MCMA children. Thirty gram of dark cocoa with 680 mg of total flavonols were given daily for 10.11 ± 3.4 days (range 9-24 days) to 18 children (10.55 years, SD = 1.45; 11F/7M). Key metabolite ratios in frontal white matter and in hippocampus pre and during cocoa intervention were quantified by magnetic resonance spectroscopy. ET-1 significantly decreased after cocoa treatment (p = 0.0002). Fifteen children (83%) showed a marginally significant individual improvement in one or both of the applied simple short memory tasks. Endothelial dysfunction is a key feature of exposure to particulate matter (PM) and decreased endothelin-1 bioavailability is likely useful for brain function in the context of air pollution. Our findings suggest that cocoa interventions may be critical for early implementation of neuroprotection of highly exposed urban children. Multi-domain nutraceutical interventions could limit the risk for endothelial dysfunction, cerebral hypoperfusion, neuroinflammation, cognitive deficits, structural volumetric detrimental brain effects, and the early development of the neuropathological hallmarks of Alzheimer's and Parkinson's diseases. PMID:23986703

  5. Flavonol-rich dark cocoa significantly decreases plasma endothelin-1 and improves cognition in urban children

    PubMed Central

    Calderón-Garcidueñas, Lilian; Mora-Tiscareño, Antonieta; Franco-Lira, Maricela; Cross, Janet V.; Engle, Randall; Aragón-Flores, Mariana; Gómez-Garza, Gilberto; Jewells, Valerie; Weili, Lin; Medina-Cortina, Humberto; Solorio, Edelmira; Chao, Chih-kai; Zhu, Hongtu; Mukherjee, Partha S.; Ferreira-Azevedo, Lara; Torres-Jardón, Ricardo; D'Angiulli, Amedeo

    2013-01-01

    Air pollution exposures are linked to systemic inflammation, cardiovascular and respiratory morbidity and mortality, neuroinflammation and neuropathology in young urbanites. In particular, most Mexico City Metropolitan Area (MCMA) children exhibit subtle cognitive deficits, and neuropathology studies show 40% of them exhibiting frontal tau hyperphosphorylation and 51% amyloid-β diffuse plaques (compared to 0% in low pollution control children). We assessed whether a short cocoa intervention can be effective in decreasing plasma endothelin 1 (ET-1) and/or inflammatory mediators in MCMA children. Thirty gram of dark cocoa with 680 mg of total flavonols were given daily for 10.11 ± 3.4 days (range 9–24 days) to 18 children (10.55 years, SD = 1.45; 11F/7M). Key metabolite ratios in frontal white matter and in hippocampus pre and during cocoa intervention were quantified by magnetic resonance spectroscopy. ET-1 significantly decreased after cocoa treatment (p = 0.0002). Fifteen children (83%) showed a marginally significant individual improvement in one or both of the applied simple short memory tasks. Endothelial dysfunction is a key feature of exposure to particulate matter (PM) and decreased endothelin-1 bioavailability is likely useful for brain function in the context of air pollution. Our findings suggest that cocoa interventions may be critical for early implementation of neuroprotection of highly exposed urban children. Multi-domain nutraceutical interventions could limit the risk for endothelial dysfunction, cerebral hypoperfusion, neuroinflammation, cognitive deficits, structural volumetric detrimental brain effects, and the early development of the neuropathological hallmarks of Alzheimer's and Parkinson's diseases. PMID:23986703

  6. Potentiation of luteolin cytotoxicity by flavonols fisetin and quercetin in human chronic lymphocytic leukemia cell lines.

    PubMed

    Sak, Katrin; Kasemaa, Kristi; Everaus, Hele

    2016-09-14

    Despite numerous studies chronic lymphocytic leukemia (CLL) still remains an incurable disease. Therefore, all new compounds and novel strategies which are able to eradicate CLL cells should be considered as valuable clues for a potential future remedy against this malignancy. In the present study, the cytotoxic profiles of natural flavonoids were described in two human CLL cell lines, HG-3 and EHEB, indicating the flavone luteolin as the most potent flavonoid with half-maximal inhibitory constants (IC50) of 37 μM and 26 μM, respectively. Luteolin significantly increased the apoptotic cell population in both cell lines by increasing the activities of caspases-3 and -9 and triggering the intrinsic apoptotic pathway. Two flavonols, fisetin and quercetin, were somewhat less efficient in suppressing cellular viability, whereas baicalein, chrysin, (+)-catechin and hesperetin exerted only a small or no response at doses as high as 100 μM. Both fisetin and quercetin were able to augment the cytotoxic activity of luteolin in both cell lines by reducing the IC50 values up to four fold. As a result of this, luteolin displayed cytotoxicity activity already at low micromolar concentrations that could potentially be physiologically achievable through oral ingestion. No other tested flavonoids were capable of sensitizing CLL cells to luteolin pointing to a specific binding of fisetin and quercetin to the cellular targets which interfere with the signaling pathways induced by luteolin. Although further molecular studies to unravel this potentiating mechanism are certainly needed, this phenomenon could contribute to future remedies for prevention and treatment of chronic lymphocytic leukemia. PMID:27489195

  7. Total Phenolic, Phenolic Acid, Anthocyanin, Flavan-3-ol, and Flavonol Profiles and Antioxidant Properties of Pinto and Black Beans ( Phaseolus vulgaris L.) as Affected by Thermal Processing.

    PubMed

    Xu, Baojun; Chang, Sam K C

    2009-06-10

    The effects of boiling and steaming processes at atmospheric and high pressures on the phenolic components and antioxidant properties of pinto and black beans were investigated. In comparison to the original raw beans, all processing methods caused significant (p < 0.05) decreases in total phenolic content (TPC), total flavonoid content (TFC), condensed tannin content (CTC), monomeric anthocyanin content (MAC), DPPH free-radical scavenging activity (DPPH), ferric-reducing antioxidant power (FRAP), and oxygen radical absorbing capacity (ORAC) values in both pinto and black beans. Steaming processing resulted in a greater retention of TPC, DPPH, FRAP, and ORAC values than the boiling processes in both pinto and black beans. To further investigate how thermal processing affected phenolic compositions and to elucidate the contribution of individual phenolic compounds to antioxidant properties, phenolic acids, anthocyanins, flavan-3-ols, and flavonols were quantitatively analyzed by high-performance liquid chromatography (HPLC). All thermal processing significantly (p < 0.05) affected individual phenolic acids, anthocyanins, flavan-3-ols, and flavonols, significantly (p < 0.05) reduced total phenolic acid contents in both pinto and black beans and total flavonol contents in pinto beans, and dramatically reduced anthocyanin contents in black beans. Phenolic acids and flavonols may play important roles on the overall antioxidant activities of pinto beans, while anthocyanins, flavan-3-ols, and flavonols may play important roles on the overall antioxidant activities of black beans.

  8. Mechanistic studies of malonic acid-mediated in situ acylation.

    PubMed

    Chandra, Koushik; Naoum, Johnny N; Roy, Tapta Kanchan; Gilon, Chaim; Gerber, R Benny; Friedler, Assaf

    2015-09-01

    We have previously introduced an easy to perform, cost-effective and highly efficient acetylation technique for solid phase synthesis (SPPS). Malonic acid is used as a precursor and the reaction proceeds via a reactive ketene that acetylates the target amine. Here we present a detailed mechanistic study of the malonic acid-mediated acylation. The influence of reaction conditions, peptide sequence and reagents was systematically studied. Our results show that the methodology can be successfully applied to different types of peptides and nonpeptidic molecules irrespective of their structure, sequence, or conformation. Using alkyl, phenyl, and benzyl malonic acid, we synthesized various acyl peptides with almost quantitative yields. The ketenes obtained from the different malonic acid derived precursors were characterized by in situ (1) H-NMR. The reaction proceeded in short reaction times and resulted in excellent yields when using uronium-based coupling agents, DIPEA as a base, DMF/DMSO/NMP as solvents, Rink amide/Wang/Merrifield resins, temperature of 20°C, pH 8-12 and 5 min preactivation at inert atmosphere. The reaction was unaffected by Lewis acids, transition metal ions, surfactants, or salt. DFT studies support the kinetically favorable concerted mechanism for CO2 and ketene formation that leads to the thermodynamically stable acylated products. We conclude that the malonic acid-mediated acylation is a general method applicable to various target molecules. PMID:25846609

  9. Acyl-CoA-Binding Proteins (ACBPs) in Plant Development.

    PubMed

    Lung, Shiu-Cheung; Chye, Mee-Len

    2016-01-01

    Acyl-CoA-binding proteins (ACBPs) play a pivotal role in fatty acid metabolism because they can transport medium- and long-chain acyl-CoA esters. In eukaryotic cells, ACBPs are involved in intracellular trafficking of acyl-CoA esters and formation of a cytosolic acyl-CoA pool. In addition to these ubiquitous functions, more specific non-redundant roles of plant ACBP subclasses are implicated by the existence of multigene families with variable molecular masses, ligand specificities, functional domains (e.g. protein-protein interaction domains), subcellular locations and gene expression patterns. In this chapter, recent progress in the characterization of ACBPs from the model dicot plant, Arabidopsis thaliana, and the model monocot, Oryza sativa, and their emerging roles in plant growth and development are discussed. The functional significance of respective members of the plant ACBP families in various developmental and physiological processes such as seed development and germination, stem cuticle formation, pollen development, leaf senescence, peroxisomal fatty acid β-oxidation and phloem-mediated lipid transport is highlighted.

  10. Preservation of polyunsaturated fatty acyl glycerides via intramolecular antioxidant coupling

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Ferulic acid and its esters are known to be effective antioxidants. Feruloyl di-gamma-linolenoylglycerol was assessed for its ability to serve as an antioxidant for preventing the oxidation of its gamma-linolenoyl polyunsaturated fatty acyl groups in model membrane phospholipid vesicles. The molec...

  11. Lubricity characteristics of seed oils modified by acylation

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Chemically modified seed oils via acylation of epoxidized and polyhydroxylated derivatives were investigated for their potential as candidates for lubrication. The native oil was preliminarily epoxidized and ring-opened in a one-pot reaction using formic acid-H2O2 followed by aqueous HCl treatment t...

  12. Acyl-CoA-Binding Proteins (ACBPs) in Plant Development.

    PubMed

    Lung, Shiu-Cheung; Chye, Mee-Len

    2016-01-01

    Acyl-CoA-binding proteins (ACBPs) play a pivotal role in fatty acid metabolism because they can transport medium- and long-chain acyl-CoA esters. In eukaryotic cells, ACBPs are involved in intracellular trafficking of acyl-CoA esters and formation of a cytosolic acyl-CoA pool. In addition to these ubiquitous functions, more specific non-redundant roles of plant ACBP subclasses are implicated by the existence of multigene families with variable molecular masses, ligand specificities, functional domains (e.g. protein-protein interaction domains), subcellular locations and gene expression patterns. In this chapter, recent progress in the characterization of ACBPs from the model dicot plant, Arabidopsis thaliana, and the model monocot, Oryza sativa, and their emerging roles in plant growth and development are discussed. The functional significance of respective members of the plant ACBP families in various developmental and physiological processes such as seed development and germination, stem cuticle formation, pollen development, leaf senescence, peroxisomal fatty acid β-oxidation and phloem-mediated lipid transport is highlighted. PMID:27023243

  13. Cell-based and in silico evidence against quercetin and structurally-related flavonols as activators of vitamin D receptor.

    PubMed

    Lau, Aik Jiang; Politi, Regina; Yang, Guixiang; Chang, Thomas K H

    2016-10-01

    It has been reported that quercetin is an activator of rat vitamin D receptor (rVDR). However, the conclusion was based on experiments performed without all the appropriate control groups, raising the possibility of a false-positive finding. Furthermore, distinct differences exist in the chemical structures of quercetin and 1α,25-dihydroxyvitamin D3, which is a prototypic agonist of VDR. Therefore, we investigated systematically whether quercetin and other flavonols are agonists of rVDR, mouse VDR (mVDR), or human VDR (hVDR). Quercetin, 3-hydroxyflavone, galangin, datiscetin, kaempferol, morin, isorhamnetin, tamarixetin, myricetin, and syringetin did not activate rVDR, mVDR, or hVDR in HEK-293 and HepG2 cells transfected with the corresponding receptor expression plasmid and either the secreted phosphoprotein 1 (Spp1) or cytochrome P450 24A1 (CYP24A1) reporter plasmid, when compared to the respective empty vector control group transfected with one or the other reporter plasmid and treated with one of the flavonols. Control analysis indicated that lithocholic acid and 1α,25-dihydroxyvitamin D3, but not rifampicin, activated rVDR, mVDR, and hVDR. As shown in transfected HEK293 and HepG2 cells, the flavonols did not influence hVDR ligand binding domain transactivation, steroid receptor coactivator-1 recruitment, or hVDR target gene expression (transient receptor potential cation channel 6 and CYP24A1) in hVDR-expressing Caco-2 or LS180 cells. The cumulative data from the cell-based experiments were corroborated by results obtained from molecular docking analysis. In conclusion, quercetin, 3-hydroxyflavone, galangin, datiscetin, kaempferol, morin, isorhamnetin, tamarixetin, myricetin, and syringetin are not agonists of rVDR, mVDR, or hVDR, as judged by cell-based and in silico evidence. PMID:27041117

  14. Cell-based and in silico evidence against quercetin and structurally-related flavonols as activators of vitamin D receptor.

    PubMed

    Lau, Aik Jiang; Politi, Regina; Yang, Guixiang; Chang, Thomas K H

    2016-10-01

    It has been reported that quercetin is an activator of rat vitamin D receptor (rVDR). However, the conclusion was based on experiments performed without all the appropriate control groups, raising the possibility of a false-positive finding. Furthermore, distinct differences exist in the chemical structures of quercetin and 1α,25-dihydroxyvitamin D3, which is a prototypic agonist of VDR. Therefore, we investigated systematically whether quercetin and other flavonols are agonists of rVDR, mouse VDR (mVDR), or human VDR (hVDR). Quercetin, 3-hydroxyflavone, galangin, datiscetin, kaempferol, morin, isorhamnetin, tamarixetin, myricetin, and syringetin did not activate rVDR, mVDR, or hVDR in HEK-293 and HepG2 cells transfected with the corresponding receptor expression plasmid and either the secreted phosphoprotein 1 (Spp1) or cytochrome P450 24A1 (CYP24A1) reporter plasmid, when compared to the respective empty vector control group transfected with one or the other reporter plasmid and treated with one of the flavonols. Control analysis indicated that lithocholic acid and 1α,25-dihydroxyvitamin D3, but not rifampicin, activated rVDR, mVDR, and hVDR. As shown in transfected HEK293 and HepG2 cells, the flavonols did not influence hVDR ligand binding domain transactivation, steroid receptor coactivator-1 recruitment, or hVDR target gene expression (transient receptor potential cation channel 6 and CYP24A1) in hVDR-expressing Caco-2 or LS180 cells. The cumulative data from the cell-based experiments were corroborated by results obtained from molecular docking analysis. In conclusion, quercetin, 3-hydroxyflavone, galangin, datiscetin, kaempferol, morin, isorhamnetin, tamarixetin, myricetin, and syringetin are not agonists of rVDR, mVDR, or hVDR, as judged by cell-based and in silico evidence.

  15. Dietary Intakes of Individual Flavanols and Flavonols Are Inversely Associated with Incident Type 2 Diabetes in European Populations123

    PubMed Central

    Zamora-Ros, Raul; Forouhi, Nita G.; Sharp, Stephen J.; González, Carlos A.; Buijsse, Brian; Guevara, Marcela; van der Schouw, Yvonne T.; Amiano, Pilar; Boeing, Heiner; Bredsdorff, Lea; Fagherazzi, Guy; Feskens, Edith J.; Franks, Paul W.; Grioni, Sara; Katzke, Verena; Key, Timothy J.; Khaw, Kay-Tee; Kühn, Tilman; Masala, Giovanna; Mattiello, Amalia; Molina-Montes, Esther; Nilsson, Peter M.; Overvad, Kim; Perquier, Florence; Redondo, M. Luisa; Ricceri, Fulvio; Rolandsson, Olov; Romieu, Isabelle; Roswall, Nina; Scalbert, Augustin; Schulze, Matthias; Slimani, Nadia; Spijkerman, Annemieke M. W.; Tjonneland, Anne; Tormo, Maria Jose; Touillaud, Marina; Tumino, Rosario; van der A, Daphne L.; van Woudenbergh, Geertruida J.; Langenberg, Claudia; Riboli, Elio; Wareham, Nicholas J.

    2014-01-01

    Dietary flavanols and flavonols, flavonoid subclasses, have been recently associated with a lower risk of type 2 diabetes (T2D) in Europe. Even within the same subclass, flavonoids may differ considerably in bioavailability and bioactivity. We aimed to examine the association between individual flavanol and flavonol intakes and risk of developing T2D across European countries. The European Prospective Investigation into Cancer and Nutrition (EPIC)–InterAct case-cohort study was conducted in 8 European countries across 26 study centers with 340,234 participants contributing 3.99 million person-years of follow-up, among whom 12,403 incident T2D cases were ascertained and a center-stratified subcohort of 16,154 individuals was defined. We estimated flavonoid intake at baseline from validated dietary questionnaires using a database developed from Phenol-Explorer and USDA databases. We used country-specific Prentice-weighted Cox regression models and random-effects meta-analysis methods to estimate HRs. Among the flavanol subclass, we observed significant inverse trends between intakes of all individual flavan-3-ol monomers and risk of T2D in multivariable models (all P-trend < 0.05). We also observed significant trends for the intakes of proanthocyanidin dimers (HR for the highest vs. the lowest quintile: 0.81; 95% CI: 0.71, 0.92; P-trend = 0.003) and trimers (HR: 0.91; 95% CI: 0.80, 1.04; P-trend = 0.07) but not for proanthocyanidins with a greater polymerization degree. Among the flavonol subclass, myricetin (HR: 0.77; 95% CI: 0.64, 0.93; P-trend = 0.001) was associated with a lower incidence of T2D. This large and heterogeneous European study showed inverse associations between all individual flavan-3-ol monomers, proanthocyanidins with a low polymerization degree, and the flavonol myricetin and incident T2D. These results suggest that individual flavonoids have different roles in the etiology of T2D. PMID:24368432

  16. A covalent adduct of MbtN, an acyl-ACP dehydrogenase from Mycobacterium tuberculosis, reveals an unusual acyl-binding pocket.

    PubMed

    Chai, Ai-Fen; Bulloch, Esther M M; Evans, Genevieve L; Lott, J Shaun; Baker, Edward N; Johnston, Jodie M

    2015-04-01

    Mycobacterium tuberculosis (Mtb) is the causative agent of tuberculosis. Access to iron in host macrophages depends on iron-chelating siderophores called mycobactins and is strongly correlated with Mtb virulence. Here, the crystal structure of an Mtb enzyme involved in mycobactin biosynthesis, MbtN, in complex with its FAD cofactor is presented at 2.30 Å resolution. The polypeptide fold of MbtN conforms to that of the acyl-CoA dehydrogenase (ACAD) family, consistent with its predicted role of introducing a double bond into the acyl chain of mycobactin. Structural comparisons and the presence of an acyl carrier protein, MbtL, in the same gene locus suggest that MbtN acts on an acyl-(acyl carrier protein) rather than an acyl-CoA. A notable feature of the crystal structure is the tubular density projecting from N(5) of FAD. This was interpreted as a covalently bound polyethylene glycol (PEG) fragment and resides in a hydrophobic pocket where the substrate acyl group is likely to bind. The pocket could accommodate an acyl chain of 14-21 C atoms, consistent with the expected length of the mycobactin acyl chain. Supporting this, steady-state kinetics show that MbtN has ACAD activity, preferring acyl chains of at least 16 C atoms. The acyl-binding pocket adopts a different orientation (relative to the FAD) to other structurally characterized ACADs. This difference may be correlated with the apparent ability of MbtN to catalyse the formation of an unusual cis double bond in the mycobactin acyl chain.

  17. Separation and quantification of 2-acyl-1-lysophospholipids and 1-acyl-2-lysophospholipids in biological samples by LC-MS/MS

    PubMed Central

    Okudaira, Michiyo; Inoue, Asuka; Shuto, Akira; Nakanaga, Keita; Kano, Kuniyuki; Makide, Kumiko; Saigusa, Daisuke; Tomioka, Yoshihisa; Aoki, Junken

    2014-01-01

    Lysophospholipids (LysoGPs) serve as lipid mediators and precursors for synthesis of diacyl phospholipids (GPs). LysoGPs detected in cells have various acyl chains attached at either the sn-1 or sn-2 position of the glycerol backbone. In general, acyl chains at the sn-2 position of 2-acyl-1-LysoGPs readily move to the sn-1 position, generating 1-acyl-2-lyso isomers by a nonenzymatic reaction called intra-molecular acyl migration, which has hampered the detection of 2-acyl-1-LysoGPs in biological samples. In this study, we developed a simple and versatile method to separate and quantify 2-acyl-1- and 1-acyl-2-LysoGPs. The main point of the method was to extract LysoGPs at pH 4 and 4°C, conditions that were found to completely eliminate the intra-molecular acyl migration. Under the present conditions, the relative amounts of 2-acyl-1-LysoGPs and 1-acyl-2-LysoGPs did not change at least for 1 week. Further, in LysoGPs extracted from cells and tissues under the present conditions, most of the saturated fatty acids (16:0 and 18:0) were found in the sn-1 position of LysoGPs, while most of the PUFAs (18:2, 20:4, 22:6) were found in the sn-2 position. Thus the method can be used to elucidate the in vivo role of 2-acyl-1-LysoGPs. PMID:25114169

  18. Ethanol Metabolism Modifies Hepatic Protein Acylation in Mice

    PubMed Central

    Fritz, Kristofer S.; Green, Michelle F.; Petersen, Dennis R.; Hirschey, Matthew D.

    2013-01-01

    Mitochondrial protein acetylation increases in response to chronic ethanol ingestion in mice, and is thought to reduce mitochondrial function and contribute to the pathogenesis of alcoholic liver disease. The mitochondrial deacetylase SIRT3 regulates the acetylation status of several mitochondrial proteins, including those involved in ethanol metabolism. The newly discovered desuccinylase activity of the mitochondrial sirtuin SIRT5 suggests that protein succinylation could be an important post-translational modification regulating mitochondrial metabolism. To assess the possible role of protein succinylation in ethanol metabolism, we surveyed hepatic sub-cellular protein fractions from mice fed a control or ethanol-supplemented diet for succinyl-lysine, as well as acetyl-, propionyl-, and butyryl-lysine post-translational modifications. We found mitochondrial protein propionylation increases, similar to mitochondrial protein acetylation. In contrast, mitochondrial protein succinylation is reduced. These mitochondrial protein modifications appear to be primarily driven by ethanol metabolism, and not by changes in mitochondrial sirtuin levels. Similar trends in acyl modifications were observed in the nucleus. However, comparatively fewer acyl modifications were observed in the cytoplasmic or the microsomal compartments, and were generally unchanged by ethanol metabolism. Using a mass spectrometry proteomics approach, we identified several candidate acetylated, propionylated, and succinylated proteins, which were enriched using antibodies against each modification. Additionally, we identified several acetyl and propionyl lysine residues on the same sites for a number of proteins and supports the idea of the overlapping nature of lysine-specific acylation. Thus, we show that novel post-translational modifications are present in hepatic mitochondrial, nuclear, cytoplasmic, and microsomal compartments and ethanol ingestion, and its associated metabolism, induce specific

  19. Mammalian long-chain acyl-CoA synthetases.

    PubMed

    Soupene, Eric; Kuypers, Frans A

    2008-05-01

    Acyl-CoA synthetase enzymes are essential for de novo lipid synthesis, fatty acid catabolism, and remodeling of membranes. Activation of fatty acids requires a two-step reaction catalyzed by these enzymes. In the first step, an acyl-AMP intermediate is formed from ATP. AMP is then exchanged with CoA to produce the activated acyl-CoA. The release of AMP in this reaction defines the superfamily of AMP-forming enzymes. The length of the carbon chain of the fatty acid species defines the substrate specificity for the different acyl-CoA synthetases (ACS). On this basis, five sub-families of ACS have been characterized. The purpose of this review is to report on the large family of mammalian long-chain acyl-CoA synthetases (ACSL), which activate fatty acids with chain lengths of 12 to 20 carbon atoms. Five genes and several isoforms generated by alternative splicing have been identified and limited information is available on their localization. The structure of these membrane proteins has not been solved for the mammalian ACSLs but homology to a bacterial form, whose structure has been determined, points at specific structural features that are important for these enzymes across species. The bacterial form acts as a dimer and has a conserved short motif, called the fatty acid Gate domain, that seems to determine substrate specificity. We will discuss the characterization and identification of the different spliced isoforms, draw attention to the inconsistencies and errors in their annotations, and their cellular localizations. These membrane proteins act on membrane-bound substrates probably as homo- and as heterodimer complexes but have often been expressed as single recombinant isoforms, apparently purified as monomers and tested in Triton X-100 micelles. We will argue that such studies have failed to provide an accurate assessment of the activity and of the distinct function of these enzymes in mammalian cells.

  20. Crystallization and preliminary X-ray crystallographic analysis of UDP-glucuronic acid:flavonol-3-O-glucuronosyltransferase (VvGT5) from the grapevine Vitis vinifera

    PubMed Central

    Mizohata, Eiichi; Okuda, Takuma; Hatanaka, Seika; Nakayama, Taisuke; Horikawa, Manabu; Nakayama, Toru; Ono, Eiichiro; Inoue, Tsuyoshi

    2013-01-01

    Grapevine (Vitis vinifera) glycosyltransferase 5 (VvGT5) is a UDP-glucuronic acid:flavonol-3-O-glucuronosyltransferase that catalyses the 3-O-specific glucuronosylation of flavonols using UDP-glucuronic acid as a sugar donor to produce flavonol 3-O-glucosides, which are important bioactive phytochemicals. Recombinant VvGT5 expressed in Escherichia coli cells was purified and crystallized by the sitting-drop vapour-diffusion method. A full set of X-ray diffraction data was collected to 2.2 Å Bragg spacing from a single crystal using a synchrotron-radiation source. The crystal was hexagonal, belonging to space group P6122, with unit-cell parameters a = b = 102.70, c = 535.92 Å. The initial phases were determined by the molecular-replacement method. PMID:23295490

  1. Acylated monogalactosyl diacylglycerol: prevalence in the plant kingdom and identification of an enzyme catalyzing galactolipid head group acylation in Arabidopsis thaliana.

    PubMed

    Nilsson, Anders K; Johansson, Oskar N; Fahlberg, Per; Kommuri, Murali; Töpel, Mats; Bodin, Lovisa J; Sikora, Per; Modarres, Masoomeh; Ekengren, Sophia; Nguyen, Chi T; Farmer, Edward E; Olsson, Olof; Ellerström, Mats; Andersson, Mats X

    2015-12-01

    The lipid phase of the thylakoid membrane is mainly composed of the galactolipids mono- and digalactosyl diacylglycerol (MGDG and DGDG, respectively). It has been known since the late 1960s that MGDG can be acylated with a third fatty acid to the galactose head group (acyl-MGDG) in plant leaf homogenates. In certain brassicaceous plants like Arabidopsis thaliana, the acyl-MGDG frequently incorporates oxidized fatty acids in the form of the jasmonic acid precursor 12-oxo-phytodienoic acid (OPDA). In the present study we further investigated the distribution of acylated and OPDA-containing galactolipids in the plant kingdom. While acyl-MGDG was found to be ubiquitous in green tissue of plants ranging from non-vascular plants to angiosperms, OPDA-containing galactolipids were only present in plants from a few genera. A candidate protein responsible for the acyl transfer was identified in Avena sativa (oat) leaf tissue using biochemical fractionation and proteomics. Knockout of the orthologous gene in A. thaliana resulted in an almost total elimination of the ability to form both non-oxidized and OPDA-containing acyl-MGDG. In addition, heterologous expression of the A. thaliana gene in E. coli demonstrated that the protein catalyzed acylation of MGDG. We thus demonstrate that a phylogenetically conserved enzyme is responsible for the accumulation of acyl-MGDG in A. thaliana. The activity of this enzyme in vivo is strongly enhanced by freezing damage and the hypersensitive response. PMID:26566971

  2. The Golgi S-acylation machinery comprises zDHHC enzymes with major differences in substrate affinity and S-acylation activity

    PubMed Central

    Lemonidis, Kimon; Gorleku, Oforiwa A.; Sanchez-Perez, Maria C.; Grefen, Christopher; Chamberlain, Luke H.

    2014-01-01

    S-acylation, the attachment of fatty acids onto cysteine residues, regulates protein trafficking and function and is mediated by a family of zDHHC enzymes. The S-acylation of peripheral membrane proteins has been proposed to occur at the Golgi, catalyzed by an S-acylation machinery that displays little substrate specificity. To advance understanding of how S-acylation of peripheral membrane proteins is handled by Golgi zDHHC enzymes, we investigated interactions between a subset of four Golgi zDHHC enzymes and two S-acylated proteins—synaptosomal-associated protein 25 (SNAP25) and cysteine-string protein (CSP). Our results uncover major differences in substrate recognition and S-acylation by these zDHHC enzymes. The ankyrin-repeat domains of zDHHC17 and zDHHC13 mediated strong and selective interactions with SNAP25/CSP, whereas binding of zDHHC3 and zDHHC7 to these proteins was barely detectable. Despite this, zDHHC3/zDHHC7 could S-acylate SNAP25/CSP more efficiently than zDHHC17, whereas zDHHC13 lacked S-acylation activity toward these proteins. Overall the results of this study support a model in which dynamic intracellular localization of peripheral membrane proteins is achieved by highly selective recruitment by a subset of zDHHC enzymes at the Golgi, combined with highly efficient S-acylation by other Golgi zDHHC enzymes. PMID:25253725

  3. New flav-3-en-3-ol glycosides, kaempferiaosides C and D, and acetophenone glycosides, kaempferiaosides E and F, from the rhizomes of Kaempferia parviflora.

    PubMed

    Chaipech, Saowanee; Morikawa, Toshio; Ninomiya, Kiyofumi; Yoshikawa, Masayuki; Pongpiriyadacha, Yutana; Hayakawa, Takao; Muraoka, Osamu

    2012-07-01

    Two new flav-3-en-3-ol glycosides, kaempferiaosides C (3) and D(4), and two new acetophenone glycosides, kaempferiaosides E (5) and F (6), were isolated from the Thai natural medicine Krachai Dum, the rhizomes of Kaempferia parviflora Wall. ex Baker. Their structures were established mainly on the basis of 1D and 2D NMR spectral data. PMID:22101441

  4. Palmitoyl-acyl carrier protein (ACP) thioesterase and the evolutionary origin of plant acyl-ACP thioesterases.

    PubMed Central

    Jones, A; Davies, H M; Voelker, T A

    1995-01-01

    Acyl-acyl carrier protein (ACP) thioesterases play an essential role in chain termination during de novo fatty acid synthesis and in the channeling of carbon flux between the two lipid biosynthesis pathways in plants. We have discovered that there are two distinct but related thioesterase gene classes in higher plants, termed FatA and FatB, whose evolutionary divergence appears to be ancient. FatA encodes the already described 18:1-ACP thioesterase. In contrast, FatB representatives encode thioesterases preferring acyl-ACPs having saturated acyl groups. We unexpectedly obtained a 16:0-ACP thioesterase cDNA from Cuphea hookeriana seed, which accumulate predominantly 8:0 and 10:0. The 16:0 thioesterase transcripts were found in non-seed tissues, and expression in transgenic Brassica napus led to the production of a 16:0-rich oil. We present evidence that this type of FatB gene is ancient and ubiquitous in plants and that specialized plant medium-chain thioesterases have evolved independently from such enzymes several times during angiosperm evolution. Also, the ubiquitous 18:1-ACP thioesterase appears to be a derivative of a 16:0 thioesterase. PMID:7734968

  5. Palmitoyl-acyl carrier protein (ACP) thioesterase and the evolutionary origin of plant acyl-ACP thioesterases.

    PubMed

    Jones, A; Davies, H M; Voelker, T A

    1995-03-01

    Acyl-acyl carrier protein (ACP) thioesterases play an essential role in chain termination during de novo fatty acid synthesis and in the channeling of carbon flux between the two lipid biosynthesis pathways in plants. We have discovered that there are two distinct but related thioesterase gene classes in higher plants, termed FatA and FatB, whose evolutionary divergence appears to be ancient. FatA encodes the already described 18:1-ACP thioesterase. In contrast, FatB representatives encode thioesterases preferring acyl-ACPs having saturated acyl groups. We unexpectedly obtained a 16:0-ACP thioesterase cDNA from Cuphea hookeriana seed, which accumulate predominantly 8:0 and 10:0. The 16:0 thioesterase transcripts were found in non-seed tissues, and expression in transgenic Brassica napus led to the production of a 16:0-rich oil. We present evidence that this type of FatB gene is ancient and ubiquitous in plants and that specialized plant medium-chain thioesterases have evolved independently from such enzymes several times during angiosperm evolution. Also, the ubiquitous 18:1-ACP thioesterase appears to be a derivative of a 16:0 thioesterase.

  6. Activation of Exogenous Fatty Acids to Acyl-Acyl Carrier Protein Cannot Bypass FabI Inhibition in Neisseria.

    PubMed

    Yao, Jiangwei; Bruhn, David F; Frank, Matthew W; Lee, Richard E; Rock, Charles O

    2016-01-01

    Neisseria is a Gram-negative pathogen with phospholipids composed of straight chain saturated and monounsaturated fatty acids, the ability to incorporate exogenous fatty acids, and lipopolysaccharides that are not essential. The FabI inhibitor, AFN-1252, was deployed as a chemical biology tool to determine whether Neisseria can bypass the inhibition of fatty acid synthesis by incorporating exogenous fatty acids. Neisseria encodes a functional FabI that was potently inhibited by AFN-1252. AFN-1252 caused a dose-dependent inhibition of fatty acid synthesis in growing Neisseria, a delayed inhibition of growth phenotype, and minimal inhibition of DNA, RNA, and protein synthesis, showing that its mode of action is through inhibiting fatty acid synthesis. Isotopic fatty acid labeling experiments showed that Neisseria encodes the ability to incorporate exogenous fatty acids into its phospholipids by an acyl-acyl carrier protein-dependent pathway. However, AFN-1252 remained an effective antibacterial when Neisseria were supplemented with exogenous fatty acids. These results demonstrate that extracellular fatty acids are activated by an acyl-acyl carrier protein synthetase (AasN) and validate type II fatty acid synthesis (FabI) as a therapeutic target against Neisseria.

  7. Lupane-triterpene glycosides from the leaves of Acanthopanax gracilistylus.

    PubMed

    Yook, Chang-Soo; Liu, Xiang-Qian; Chang, Seung-Yeup; Park, Sang-Yong; Nohara, Toshihiro

    2002-10-01

    A novel lupane-triterpene glycoside, called wujiapioside B (1), was isolated from the leaves of Acanthopanax gracilistylus (Araliaceae) together with three known lupane-triterpene glycosides, acankoreoside C (2), acantrifoside A (3) and 3-epibetulinic acid 28-O-alpha-L-rhamnopyranosyl-(1-->4)-beta-D-glucopyranosyl-(1-->6)-beta-D-glucopyranosyl ester (4). Based on spectroscopic data, the chemical structure of 1 was determined as 3alpha,23-dihydroxy-lup-20(29)-en-28-oic acid 28-O-alpha-L-rhamnopyranosyl-(1-->4)-beta-D-glucopyranosyl-(1-->6)-beta-D-glucopyranosyl ester. Compounds 2-3 were obtained for the first time from this plant and compound 4 has not been isolated from Acanthopanax genus yet. PMID:12372869

  8. Croton ruizianus: platelet proaggregating activity of two new pregnane glycosides.

    PubMed

    Piacente, S; Belisario, M A; Del Castillo, H; Pizza, C; De Feo, V

    1998-03-01

    The MeOH extract of the aerial parts of Croton ruizianus afforded two new pregnane glycosides 1 and 2, together with the morphinandienone alkaloids flavinantine (3) and O-methylflavinantine (4). Their structures were elucidated by NMR experiments including 1H-1H (1D TOCSY and 2D DQF-COSY) and 1H-13C (HSQC, HMBC) spectroscopy. The proaggregating activity of the MeOH extract and the isolates were evaluated. Although the MeOH extract and pregnane glycosides (at different doses) were found to promote platelet aggregation, flavinantine (3) and O-methylflavinantine (4) showed only slight activity. The ability of the MeOH extract and the four compounds to act synergistically with thrombin was also evaluated. All the tested compounds were successful in augmenting the aggregating effect of thrombin, although to different degrees.

  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. 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

  12. 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.

  13. Direct N-acylation of azoles via a metal-free catalyzed oxidative cross-coupling strategy.

    PubMed

    Zhao, Jingjing; Li, Pan; Xia, Chungu; Li, Fuwei

    2014-05-11

    The KI-catalyzed N-acylation of azoles via direct oxidative coupling of C-H and N-H bonds has been developed. It could be smoothly scaled up to gram synthesis of acyl azoles. The reaction occurred by the coupling of acyl radicals and azoles to form the acyl azole radical anion, followed by its further oxidation.

  14. Phenylpropanoid glycosides from the leaves of Paulownia coreana.

    PubMed

    Kim, Jin-Kyu; Si, Chuan-Ling; Bae, Young-Soo

    2008-02-15

    Study on the water soluble fraction from the leaves of Paulownia coreana led to the isolation of verbascoside (1), isoverbascoside (2), campneoside II (3), and a new phenylpropanoid glycoside, (R,S)-7-hydroxy-7-(3,4-dihydroxyphenyl)-ethyl-O-alpha-L-rhamnopyranosyl(1 --> 3)-beta-d-(6-O-caffeoyl)-glucopyranoside (4). The structures of these compounds were established on the basis of spectroscopic evidence. PMID:18266154

  15. A new triterpene glycoside from the roots of Symphytum officinale.

    PubMed

    Ahmad, V U; Noorwala, M; Mohammad, F V; Sener, B

    1993-03-01

    Chemical investigation of the EtOH-soluble portion of Symphytum officinale roots has resulted in the isolation of a new pentacyclic triterpene glycoside of oleanolic acid. Its structure was elucidated by spectroscopic studies, including 2D nmr, and chemical evidences as 3-O-[beta-D-glucopyranosyl-(1-->4)-beta-D-glucopyranosyl-(1-->4)-alpha-L -arabinopyranosyl]-oleanolic acid [1]. PMID:8482944

  16. Two aurone glycosides from heartwood of Pterocarpus santalinus.

    PubMed

    Kesari, Achyut Narayan; Gupta, Rajesh Kumar; Watal, Geeta

    2004-12-01

    Two new aurone glycosides, 6 hydroxy 5 methyl 3',4',5' trimethoxy aurone 4-O-alpha-L-rhamnopyranoside and 6,4' dihydroxy aurone 4-O-rutinoside have been isolated from the ethanolic extract of the wood of Pterocarpus santalinus. Their structures were determined on the basis of chemical and spectroscopic analysis (UV, IR, EIMS, (1)H and (13)C NMR). PMID:15541741

  17. New phenolic glycosides from the seeds of Cucurbita moschata.

    PubMed

    Li, Fa-Sheng; Dou, De-Qiang; Xu, Liang; Chi, Xiao-Feng; Kang, Ting-Guo; Kuang, Hai-Xue

    2009-07-01

    Two new phenolic glycosides were isolated from the seeds of Cucurbita moschata. Their structures were elucidated as (2-hydroxy)phenylcarbinyl 5-O-benzoyl-beta-D-apiofuranosyl(1-->2)-beta-D-glucopyranoside (1) and 4-beta-D-(glucopyranosyl hydroxymethyl)phenyl 5-O-benzoyl-beta-D-apiofuranosyl(1-->2)-beta-D-glucopyranoside (2) on the basis of spectroscopic analysis and chemical evidence.

  18. Vina-Carb: Improving Glycosidic Angles during Carbohydrate Docking.

    PubMed

    Nivedha, Anita K; Thieker, David F; Makeneni, Spandana; Hu, Huimin; Woods, Robert J

    2016-02-01

    Molecular docking programs are primarily designed to align rigid, drug-like fragments into the binding sites of macromolecules and frequently display poor performance when applied to flexible carbohydrate molecules. A critical source of flexibility within an oligosaccharide is the glycosidic linkages. Recently, Carbohydrate Intrinsic (CHI) energy functions were reported that attempt to quantify the glycosidic torsion angle preferences. In the present work, the CHI-energy functions have been incorporated into the AutoDock Vina (ADV) scoring function, subsequently termed Vina-Carb (VC). Two user-adjustable parameters have been introduced, namely, a CHI- energy weight term (chi_coeff) that affects the magnitude of the CHI-energy penalty and a CHI-cutoff term (chi_cutoff) that negates CHI-energy penalties below a specified value. A data set consisting of 101 protein-carbohydrate complexes and 29 apoprotein structures was used in the development and testing of VC, including antibodies, lectins, and carbohydrate binding modules. Accounting for the intramolecular energies of the glycosidic linkages in the oligosaccharides during docking led VC to produce acceptable structures within the top five ranked poses in 74% of the systems tested, compared to a success rate of 55% for ADV. An enzyme system was employed in order to illustrate the potential application of VC to proteins that may distort glycosidic linkages of carbohydrate ligands upon binding. VC represents a significant step toward accurately predicting the structures of protein-carbohydrate complexes. Furthermore, the described approach is conceptually applicable to any class of ligands that populate well-defined conformational states. PMID:26744922

  19. Two new monoterpenoid glycosides from Mentha spicata L.

    PubMed

    Zheng, Jian; Wu, Li-Jun; Zheng, Lu; Wu, Bin; Song, Ai-Hua

    2003-03-01

    Two new monoterpenoid glycosides, spicatoside A and spicatoside B, were isolated from the whole herbs of Mentha spicata L. which have anti-inflammatory and hemostatic activities. Their structures have been determined on the basis of spectral and chemical analysis. They are (+)-5-[1-(beta-D-glucopyranosyloxymethyl)ethenyl]-2-methyl-2-cyclohexen-1-one (1), and (-)-5-[[2-(beta-D-glucopyranosyloxy)-1-hydroxy-l-methyl]ethyl]-2-methyl-2-cyclohexen-1-one (2).

  20. New Iridoid Glycosides with Antidepressant Activity Isolated from Cyperus rotundus.

    PubMed

    Zhou, Zhong-Liu; Yin, Wen-Qing; Yang, Ya-Mei; He, Chun-Hong; Li, Xiao-Na; Zhou, Cui-Ping; Guo, Hong

    2016-01-01

    Based on bioactive screening results, two new iridoid glycosides, named rotunduside G (1) and rotunduside H (2), were isolated from the rhizomes of Cyperus rotundus, together with four known ones, negundoside (3), nishindaside (4), isooleuropein (5) and neonuezhenide (6). Their structures were elucidated on the basis of spectroscopic methods and from literature values. In mice models of despair, 1 and 2 showed significant antidepressant activity. PMID:26726748

  1. Production of a Brassica napus low-molecular mass acyl-coenzyme A-binding protein in Arabidopsis alters the acyl-coenzyme A pool and acyl composition of oil in seeds

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Low-molecular mass (10 kD) cytosolic acyl-coenzyme A-binding protein (ACBP) has a substantial influence over fatty acid (FA) composition in oilseeds, possibly via an effect on the partitioning of acyl groups between elongation and desaturation pathways. Previously, we demonstrated that the expressio...

  2. Simultaneous separation by reversed-phase high-performance liquid chromatography and mass spectral identification of anthocyanins and flavonols in Shiraz grape skin.

    PubMed

    Downey, Mark O; Rochfort, Simone

    2008-08-01

    A limitation of large-scale viticultural trials is the time and cost of comprehensive compositional analysis of the fruit by high-performance liquid chromatography (HPLC). In addition, separate methods have generally been required to identify and quantify different classes of metabolites. To address these shortcomings a reversed-phase HPLC method was developed to simultaneously separate the anthocyanins and flavonols present in grape skins. The method employs a methanol and water gradient acidified with 10% formic acid with a run-time of 48 min including re-equilibration. Identity of anthocyanins and flavonols in Shiraz (Vitis vinifera L.) skin was confirmed by mass spectral analysis. PMID:18573501

  3. Glycosidic linkage conformation of methyl-α-mannopyranoside

    NASA Astrophysics Data System (ADS)

    Coskuner, Orkid; Bergeron, Denis E.; Rincon, Luis; Hudgens, Jeffrey W.; Gonzalez, Carlos A.

    2008-07-01

    We study the preferred conformation of the glycosidic linkage of methyl-α-mannopyranoside in the gas phase and in aqueous solution. Results obtained utilizing Car-Parrinello molecular dynamics (CPMD) simulations are compared to those obtained from classical molecular dynamics (MD) simulations. We describe classical simulations performed with various water potential functions to study the impact of the chosen water potential on the predicted conformational preference of the glycosidic linkage of the carbohydrate in aqueous solution. In agreement with our recent studies, we find that results obtained with CPMD simulations differ from those obtained from classical simulations. In particular, this study shows that the trans (t) orientation of the glycosidic linkage of methyl-α-mannopyranoside is preferred over its gauche anticlockwise (g-) orientation in aqueous solution. CPMD simulations indicate that this preference is due to intermolecular hydrogen bonding with surrounding water molecules, whereas no such information could be demonstrated by classical MD simulations. This study emphasizes the importance of ab initio MD simulations for studying the structural properties of carbohydrates in aqueous solution.

  4. Minor diterpene glycosides from the leaves of Stevia rebaudiana.

    PubMed

    Ibrahim, Mohamed A; Rodenburg, Douglas L; Alves, Kamilla; Fronczek, Frank R; McChesney, James D; Wu, Chongming; Nettles, Brian J; Venkataraman, Sylesh K; Jaksch, Frank

    2014-05-23

    Two new diterpene glycosides in addition to five known glycosides have been isolated from a commercial extract of the leaves of Stevia rebaudiana. Compound 1 (rebaudioside KA) was shown to be 13-[(O-β-d-glucopyranosyl)oxy]ent-kaur-16-en-19-oic acid 2-O-β-d-glucopyranosyl-β-d-glucopyranosyl ester and compound 2, 12-α-[(2-O-β-d-glucopyranosyl-β-d-glucopyranosyl)oxy]ent-kaur-16-en-19-oic acid β-d-glucopyranosyl ester. Five additional known compounds were identified, rebaudioside E, rebaudioside M, rebaudioside N, rebaudioside O, and stevioside, respectively. Enzymatic hydrolysis of stevioside afforded the known ent-kaurane aglycone 13-hydroxy-ent-kaur-16-en-19-oic acid (steviol) (3). The isolated metabolite 1 possesses the ent-kaurane aglycone steviol (3), while compound 2 represents the first example of the isomeric diterpene 12-α-hydroxy-ent-kaur-16-en-19-oic acid existing as a glycoside in S. rebaudiana. The structures of the isolated metabolites 1 and 2 were determined based on comprehensive 1D- and 2D-NMR (COSY, HSQC, and HMBC) studies. A high-quality crystal of compound 3 has formed, which allowed the acquisition of X-ray diffraction data that confirmed its structure. The structural similarities between the new metabolites and the commercially available stevioside sweeteners suggest the newly isolated metabolites should be examined for their organoleptic properties. Accordingly rebaudiosides E, M, N, O, and KA have been isolated in greater than gram quantities.

  5. Flavonol Glucoside and Antioxidant Enzyme Biosynthesis Affected by Mycorrhizal Fungi in Various Cultivars of Onion (Allium cepa L.).

    PubMed

    Mollavali, Mohanna; Bolandnazar, Saheb Ali; Schwarz, Dietmar; Rohn, Sascha; Riehle, Peer; Zaare Nahandi, Fariborz

    2016-01-13

    The objective of this study was to investigate the impact of mycorrhizal symbiosis on qualitative characteristics of onion (Allium cepa L.). For this reason, five onion cultivars with different scale color and three different strains of arbuscular mycorrhizal fungi (Diversispora versiformis, Rhizophagus intraradices, Funneliformis mosseae) were used. Red cultivars, mainly 'Red Azar-shahr', showed the highest content in vitamin C, flavonols, and antioxidant enzymes. Mycorrhizal inoculation increased total phenolic, pyruvic acid, and vitamin C of onion plants. Considerable increase was observed in quercetin-4'-O-monoglucoside and isorhamnetin-4'-O-monoglucoside content in plants inoculated with Diversispora versiformis, but quercetin-3,4'-O-diglucoside was not significantly influenced. Analyses for phenylalanine ammonia-lyase (PAL) and antioxiodant enzyme activities such as polyphenol oxidase (PPO), catalase (CAT), and peroxidase (POD) revealed that all except PPO were enhanced by mycorrhizal inoculation. Overall, these findings suggested that mycorrhizal inoculation influenced biosynthesis of flavonol glucosides and antioxidant enzymes by increasing nutrient uptake or by induction of the plant defense system. PMID:26694086

  6. Developmental profile of anthocyanin, flavonol, and proanthocyanidin type, content, and localization in saskatoon fruits (Amelanchier alnifolia Nutt.).

    PubMed

    Jin, Alena L; Ozga, Jocelyn A; Kennedy, James A; Koerner-Smith, Jayma L; Botar, Gabor; Reinecke, Dennis M

    2015-02-11

    Saskatoons (Amelanchier alnifolia Nutt.) are small fruits that contain substantial quantities of flavonoids. To further characterize and understand the role of these flavonoids during fruit development, anthocyanins, flavonols, and proanthocyanidins were identified, quantified, and localized over development in cultivars that produce blue-purple or white fruit at maturity. Anthocyanin content was low in young fruit and then dramatically increased as the fruit transitioned into ripening only in the pigmented-fruit (blue-purple) cultivars. Proanthocyanidins with both A-type and B-type linkages were detected in fruit, with (-)-epicatechin as the most abundant proanthocyanidin subunit. Flavonol and proanthocyanidin content was high in, and localized throughout, the tissues of young fruit and in the developing seed coats, with levels decreasing as the fruit expanded. Our data show that flavonoid type, content, and tissue localization vary throughout development in saskatoon fruit. These data can be used to target specific fruit developmental stages and flavonoid classes for optimization of health-beneficial flavonoid content.

  7. Flavonol Glucoside and Antioxidant Enzyme Biosynthesis Affected by Mycorrhizal Fungi in Various Cultivars of Onion (Allium cepa L.).

    PubMed

    Mollavali, Mohanna; Bolandnazar, Saheb Ali; Schwarz, Dietmar; Rohn, Sascha; Riehle, Peer; Zaare Nahandi, Fariborz

    2016-01-13

    The objective of this study was to investigate the impact of mycorrhizal symbiosis on qualitative characteristics of onion (Allium cepa L.). For this reason, five onion cultivars with different scale color and three different strains of arbuscular mycorrhizal fungi (Diversispora versiformis, Rhizophagus intraradices, Funneliformis mosseae) were used. Red cultivars, mainly 'Red Azar-shahr', showed the highest content in vitamin C, flavonols, and antioxidant enzymes. Mycorrhizal inoculation increased total phenolic, pyruvic acid, and vitamin C of onion plants. Considerable increase was observed in quercetin-4'-O-monoglucoside and isorhamnetin-4'-O-monoglucoside content in plants inoculated with Diversispora versiformis, but quercetin-3,4'-O-diglucoside was not significantly influenced. Analyses for phenylalanine ammonia-lyase (PAL) and antioxiodant enzyme activities such as polyphenol oxidase (PPO), catalase (CAT), and peroxidase (POD) revealed that all except PPO were enhanced by mycorrhizal inoculation. Overall, these findings suggested that mycorrhizal inoculation influenced biosynthesis of flavonol glucosides and antioxidant enzymes by increasing nutrient uptake or by induction of the plant defense system.

  8. Characterization of a Bifunctional Archaeal Acyl Coenzyme A Carboxylase

    PubMed Central

    Chuakrut, Songkran; Arai, Hiroyuki; Ishii, Masaharu; Igarashi, Yasuo

    2003-01-01

    Acyl coenzyme A carboxylase (acyl-CoA carboxylase) was purified from Acidianus brierleyi. The purified enzyme showed a unique subunit structure (three subunits with apparent molecular masses of 62, 59, and 20 kDa) and a molecular mass of approximately 540 kDa, indicating an α4β4γ4 subunit structure. The optimum temperature for the enzyme was 60 to 70°C, and the optimum pH was around 6.4 to 6.9. Interestingly, the purified enzyme also had propionyl-CoA carboxylase activity. The apparent Km for acetyl-CoA was 0.17 ± 0.03 mM, with a Vmax of 43.3 ± 2.8 U mg−1, and the Km for propionyl-CoA was 0.10 ± 0.008 mM, with a Vmax of 40.8 ± 1.0 U mg−1. This result showed that A. brierleyi acyl-CoA carboxylase is a bifunctional enzyme in the modified 3-hydroxypropionate cycle. Both enzymatic activities were inhibited by malonyl-CoA, methymalonyl-CoA, succinyl-CoA, or CoA but not by palmitoyl-CoA. The gene encoding acyl-CoA carboxylase was cloned and characterized. Homology searches of the deduced amino acid sequences of the 62-, 59-, and 20-kDa subunits indicated the presence of functional domains for carboxyltransferase, biotin carboxylase, and biotin carboxyl carrier protein, respectively. Amino acid sequence alignment of acetyl-CoA carboxylases revealed that archaeal acyl-CoA carboxylases are closer to those of Bacteria than to those of Eucarya. The substrate-binding motifs of the enzymes are highly conserved among the three domains. The ATP-binding residues were found in the biotin carboxylase subunit, whereas the conserved biotin-binding site was located on the biotin carboxyl carrier protein. The acyl-CoA-binding site and the carboxybiotin-binding site were found in the carboxyltransferase subunit. PMID:12533469

  9. Annotation and comparative analysis of the glycoside hydrolase genes in Brachypodium distachyon

    SciTech Connect

    Tyler, Ludmila; Bragg, Jennifer; Wu, Jiajie; Yang, Xiaohan; Tuskan, Gerald A; Vogel, John

    2010-01-01

    Background Glycoside hydrolases cleave the bond between a carbohydrate and another carbohydrate, a protein, lipid or other moiety. Genes encoding glycoside hydrolases are found in a wide range of organisms, from archea to animals, and are relatively abundant in plant genomes. In plants, these enzymes are involved in diverse processes, including starch metabolism, defense, and cell-wall remodeling. Glycoside hydrolase genes have been previously cataloged for Oryza sativa (rice), the model dicotyledonous plant Arabidopsis thaliana, and the fast-growing tree Populus trichocarpa (poplar). To improve our understanding of glycoside hydrolases in plants generally and in grasses specifically, we annotated the glycoside hydrolase genes in the grasses Brachypodium distachyon (an emerging monocotyledonous model) and Sorghum bicolor (sorghum). We then compared the glycoside hydrolases across species, both at the whole-genome level and at the level of individual glycoside hydrolase families. Results We identified 356 glycoside hydrolase genes in Brachypodium and 404 in sorghum. The corresponding proteins fell into the same 34 families that are represented in rice, Arabidopsis, and poplar, helping to define a glycoside hydrolase family profile which may be common to flowering plants. Examination of individual glycoside hydrolase familes (GH5, GH13, GH18, GH19, GH28, and GH51) revealed both similarities and distinctions between monocots and dicots, as well as between species. Shared evolutionary histories appear to be modified by lineage-specific expansions or deletions. Within families, the Brachypodium and sorghum proteins generally cluster with those from other monocots. Conclusions This work provides the foundation for further comparative and functional analyses of plant glycoside hydrolases. Defining the Brachypodium glycoside hydrolases sets the stage for Brachypodium to be a monocot model for investigations of these enzymes and their diverse roles in planta. Insights

  10. Multidrug resistance-reversal effects of resin glycosides from Dichondra repens.

    PubMed

    Song, Wei-Bin; Wang, Wen-Qiong; Zhang, Shu-Wei; Xuan, Li-Jiang

    2015-02-15

    Investigation of hydrophobic extract of Dichondra repens (Convolvulaceae) led to the isolation of three new resin glycosides dichondrins A-C (1-3), and three known resin glycosides cus-1, cus-2, and cuse 3. All the isolated resin glycosides with an acyclic core were evaluated for their multidrug resistance reversal activities, and the combined use of these compounds at a concentration of 25μM increased the cytotoxicity of vincristine by 1.03-1.78-fold.

  11. New aliphatic alcohol and (Z)-4-coumaric acid glycosides from Acanthus ilicifolius.

    PubMed

    Wu, Jun; Zhang, Si; Huang, Jianshe; Xiao, Qiang; Li, Qingxin; Long, Lijuan; Huang, Liangmin

    2003-10-01

    From the aerial parts of Acanthus ilicifolius, a new aliphatic alcohol glycoside (ilicifolioside C) and two new (Z)-4-coumaric acid glycosides, (Z)-4-coumaric acid 4-O-beta-D-glucopyranoside and (Z)-4-coumaric acid 4-O-beta-D-apiofuranosyl-(1"-->2')-O-beta-D-glucopyranoside were isolated. The structural elucidations were based on the analyses of spectroscopic data. Z-Form 4-coumaric acid glycosides were first isolated from plant.

  12. 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

  13. Three new alkaloids and three new phenolic glycosides from Liparis odorata.

    PubMed

    Jiang, Piao; Liu, Hongdong; Xu, Xianghong; Liu, Bo; Zhang, Dongming; Lai, Xuewen; Zhu, Genghua; Xu, Peng; Li, Bin

    2015-12-01

    Three new alkaloids, liparis alkaloid A (1), B (2), C (3), and three new phenolic glycosides, liparis glycoside H (4), I (5), J (6), together with three known phenolic glycosides (7-9) were isolated from the whole plant of Liparis odorata. Their structures were characterized on the basis of extensive 1D-, 2D-NMR and HR-ESI-MS experiments. In addition, compounds 1-3 revealed hypolipidemic effects in the in vitro bioassays, and the ability to inhibit LPS-induced NO production of these isolated phenolic glycosides (4-9) was also evaluated.

  14. Glycosides from marine sponges (Porifera, Demospongiae): structures, taxonomical distribution, biological activities and biological roles.

    PubMed

    Kalinin, Vladimir I; Ivanchina, Natalia V; Krasokhin, Vladimir B; Makarieva, Tatyana N; Stonik, Valentin A

    2012-08-01

    Literature data about glycosides from sponges (Porifera, Demospongiae) are reviewed. Structural diversity, biological activities, taxonomic distribution and biological functions of these natural products are discussed.

  15. Glycosides from Marine Sponges (Porifera, Demospongiae): Structures, Taxonomical Distribution, Biological Activities and Biological Roles

    PubMed Central

    Kalinin, Vladimir I.; Ivanchina, Natalia V.; Krasokhin, Vladimir B.; Makarieva, Tatyana N.; Stonik, Valentin A.

    2012-01-01

    Literature data about glycosides from sponges (Porifera, Demospongiae) are reviewed. Structural diversity, biological activities, taxonomic distribution and biological functions of these natural products are discussed. PMID:23015769

  16. Reaction of Acylated Homoserine Lactone Bacterial Signaling Molecules with Oxidized Halogen Antimicrobials

    PubMed Central

    Borchardt, S. A.; Allain, E. J.; Michels, J. J.; Stearns, G. W.; Kelly, R. F.; McCoy, W. F.

    2001-01-01

    Oxidized halogen antimicrobials, such as hypochlorous and hypobromous acids, have been used extensively for microbial control in industrial systems. Recent discoveries have shown that acylated homoserine lactone cell-to-cell signaling molecules are important for biofilm formation in Pseudomonas aeruginosa, suggesting that biofouling can be controlled by interfering with bacterial cell-to-cell communication. This study was conducted to investigate the potential for oxidized halogens to react with acylated homoserine lactone-based signaling molecules. Acylated homoserine lactones containing a 3-oxo group were found to rapidly react with oxidized halogens, while acylated homoserine lactones lacking the 3-oxo functionality did not react. The Chromobacterium violaceum CV026 bioassay was used to determine the effects of such reactions on acylated homoserine lactone activity. The results demonstrated that 3-oxo acyl homoserine lactone activity was rapidly lost upon exposure to oxidized halogens; however, acylated homoserine lactones lacking the 3-oxo group retained activity. Experiments with the marine alga Laminaria digitata demonstrated that natural haloperoxidase systems are capable of mediating the deactivation of acylated homoserine lactones. This may illustrate a natural defense mechanism to prevent biofouling on the surface of this marine alga. The Chromobacterium violaceum activity assay illustrates that reactions between 3-oxo acylated homoserine lactone molecules and oxidized halogens do occur despite the presence of biofilm components at much greater concentrations. This work suggests that oxidized halogens may control biofilm not only via a cidal mechanism, but also by possibly interfering with 3-oxo acylated homoserine lactone-based cell signaling. PMID:11425738

  17. 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.

  18. Glycosyltransferases from oat (Avena) implicated in the acylation of avenacins.

    PubMed

    Owatworakit, Amorn; Townsend, Belinda; Louveau, Thomas; Jenner, Helen; Rejzek, Martin; Hughes, Richard K; Saalbach, Gerhard; Qi, Xiaoquan; Bakht, Saleha; Roy, Abhijeet Deb; Mugford, Sam T; Goss, Rebecca J M; Field, Robert A; Osbourn, Anne

    2013-02-01

    Plants produce a huge array of specialized metabolites that have important functions in defense against biotic and abiotic stresses. Many of these compounds are glycosylated by family 1 glycosyltransferases (GTs). Oats (Avena spp.) make root-derived antimicrobial triterpenes (avenacins) that provide protection against soil-borne diseases. The ability to synthesize avenacins has evolved since the divergence of oats from other cereals and grasses. The major avenacin, A-1, is acylated with N-methylanthranilic acid. Previously, we have cloned and characterized three genes for avenacin synthesis (for the triterpene synthase SAD1, a triterpene-modifying cytochrome P450 SAD2, and the serine carboxypeptidase-like acyl transferase SAD7), which form part of a biosynthetic gene cluster. Here, we identify a fourth member of this gene cluster encoding a GT belonging to clade L of family 1 (UGT74H5), and show that this enzyme is an N-methylanthranilic acid O-glucosyltransferase implicated in the synthesis of avenacin A-1. Two other closely related family 1 GTs (UGT74H6 and UGT74H7) are also expressed in oat roots. One of these (UGT74H6) is able to glucosylate both N-methylanthranilic acid and benzoic acid, whereas the function of the other (UGT74H7) remains unknown. Our investigations indicate that UGT74H5 is likely to be key for the generation of the activated acyl donor used by SAD7 in the synthesis of the major avenacin, A-1, whereas UGT74H6 may contribute to the synthesis of other forms of avenacin that are acylated with benzoic acid.

  19. The ɛ-Amino Group of Protein Lysine Residues Is Highly Susceptible to Nonenzymatic Acylation by Several Physiological Acyl-CoA Thioesters.

    PubMed

    Simic, Zeljko; Weiwad, Matthias; Schierhorn, Angelika; Steegborn, Clemens; Schutkowski, Mike

    2015-11-01

    Mitochondrial enzymes implicated in the pathophysiology of diabetes, cancer, and metabolic syndrome are highly regulated by acetylation. However, mitochondrial acetyltransferases have not been identified. Here, we show that acetylation and also other acylations are spontaneous processes that depend on pH value, acyl-CoA concentration and the chemical nature of the acyl residue. In the case of a peptide derived from carbamoyl phosphate synthetase 1, the rates of succinylation and glutarylation were up to 150 times than for acetylation. These results were confirmed by using the protein substrate cyclophilin A (CypA). Deacylation experiments revealed that SIRT3 exhibits deacetylase activity but is not able to remove any of the succinyl groups from CypA, whereas SIRT5 is an effective protein desuccinylase. Thus, the acylation landscape on lysine residues might largely depend on the enzymatic activity of specific sirtuins, and the availability and reactivity of acyl-CoA compounds. PMID:26382620

  20. The functional size of acyl-coenzyme A (CoA):cholesterol acyltransferase and acyl-CoA hydrolase as determined by radiation inactivation

    SciTech Connect

    Billheimer, J.T.; Cromley, D.A.; Kempner, E.S. )

    1990-05-25

    Frozen rat liver microsomes and rough endoplasmic reticulum were irradiated with high energy electrons. The surviving enzymatic activity of acyl-CoA:cholesterol acyltransferase and activity for esterification of 25-hydroxycholesterol decreased as a simple exponential function of radiation exposure, leading to a target size of 170-180 kDa. The loss of acyl-CoA hydrolase activity with a radiation dose was complex and resolved as a 45-kDa enzyme associated with a large inhibitor. It is interpreted that acyl-CoA hydrolase is the acyl-CoA-binding component and the inhibitor is the cholesterol-binding component of acyl-CoA:cholesterol acyltransferase.

  1. Metabolism of acyl-lipids in Chlamydomonas reinhardtii.

    PubMed

    Li-Beisson, Yonghua; Beisson, Fred; Riekhof, Wayne

    2015-05-01

    Microalgae are emerging platforms for production of a suite of compounds targeting several markets, including food, nutraceuticals, green chemicals, and biofuels. Many of these products, such as biodiesel or polyunsaturated fatty acids (PUFAs), derive from lipid metabolism. A general picture of lipid metabolism in microalgae has been deduced from well characterized pathways of fungi and land plants, but recent advances in molecular and genetic analyses of microalgae have uncovered unique features, pointing out the necessity to study lipid metabolism in microalgae themselves. In the past 10 years, in addition to its traditional role as a model for photosynthetic and flagellar motility processes, Chlamydomonas reinhardtii has emerged as a model organism to study lipid metabolism in green microalgae. Here, after summarizing data on total fatty acid composition, distribution of acyl-lipid classes, and major acyl-lipid molecular species found in C. reinhardtii, we review the current knowledge on the known or putative steps for fatty acid synthesis, glycerolipid desaturation and assembly, membrane lipid turnover, and oil remobilization. A list of characterized or putative enzymes for the major steps of acyl-lipid metabolism in C. reinhardtii is included, and subcellular localizations and phenotypes of associated mutants are discussed. Biogenesis and composition of Chlamydomonas lipid droplets and the potential importance of lipolytic processes in increasing cellular oil content are also highlighted.

  2. 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

  3. Naphthalene Derivatives Induce Acyl Chain Interdigitation in Dipalmitoylphosphatidylcholine Bilayers.

    PubMed

    Kamal, Md Arif; Raghunathan, V A

    2016-01-14

    The interdigitated phase of the lipid bilayer results when acyl chains from opposing monolayers fully interpenetrate such that the terminal methyl groups of the respective lipid chains are located at the interfacial region on the opposite sides of the bilayer. Usually, chain interdigitation is not encountered in a symmetric chain phosphatidylcholine (PC) membrane but can be induced under certain special conditions. In this article, we elucidate the contribution of small amphiphatic molecules in altering the physical properties of a symmetric chain PC bilayer membrane, which results in acyl chain interdigitation. Using small-angle X-ray scattering (SAXS), we have carried out a systematic investigation of the physical interactions of three naphthalene derivatives containing hydroxyl groups: β-naphthol, 2,3-dihydroxynaphthalene, and 2,7-dihydroxynaphthalene, with dipalmitoylphosphatidylcholine (DPPC) bilayers. On the basis of the diffraction patterns, we have determined the temperature-composition phase diagrams of these binary mixtures. The present study not only enables us to gain insight into the role played by small molecules in altering the packing arrangement of the acyl chains of the constituting PC lipids of the bilayer but also brings to light some important features that have not yet been reported hitherto. One such feature is the stabilization of the enigmatic asymmetric ripple phase over a wide temperature and concentration range. The results presented here strongly point toward a clear correlation between chain interdigitation and the stability of the ripple phase.

  4. Fatty acid acylation of salivary mucin in rat submandibular glands

    SciTech Connect

    Slomiany, B.L.; Murty, V.L.; Takagi, A.; Tsukada, H.; Kosmala, M.; Slomiany, A.

    1985-11-01

    The acylation of salivary mucin with fatty acids and its biosynthesis was investigated by incubating rat submandibular salivary gland cells with (/sup 3/H)palmitic acid and (/sup 3/H)proline. The elaborated extracellular and intracellular mucus glycoproteins following delipidation, Bio-Gel P-100 chromatography, and CsCl equilibrium density gradient centrifugation were analyzed for the distribution of the labeled tracers. The incorporation of both markers into mucus glycoprotein increased steadily with time up to 4 h, at which time about 65% of (/sup 3/H)palmitate and (/sup 3/H)proline were found in the extracellular glycoprotein and 35% in the intracellular glycoprotein. The incorporation ratio of proline/palmitate, while showing an increase with incubation time in the extracellular glycoprotein, remained essentially unchanged with time in the intracellular glycoprotein and at 4 h reached respective values of 0.14 and 1.12. The fact that the proline/palmitate incorporation ratio in the intracellular glycoprotein at 1 h of incubation was 22 times higher than in the extracellular and 8 times higher after 4 h suggests that acylation occurs intracellularly and that fatty acids are added after apomucin polypeptide synthesis. As the incorporation of palmitate within the intracellular mucin was greater in the mucus glycoprotein subunit, it would appear that fatty acid acylation of mucin subunits preceeds their assembly into the mucus glycoprotein polymer.

  5. Determination of Ginkgolides and Flavonols in Ginkgo Biloba Products and NIST Ginkgo Reference Standard by LC/UV/MS (Experimental Biology, April, 2007, Washington, D.C.)

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The leaf extract of Ginkgo biloba has purported value for improving mental capacities in Alzheimer’s patients. The flavonols and the terpene lactones are considered to be the two main active components that influence human health. Almost all the clinical studies regarding Ginkgo biloba used either...

  6. Antioxidant and antiatherogenic properties of phenolic acid and flavonol fractions of fruits of 'Amari' and 'Hallawi' date (Phoenix dactylifera L.) varieties.

    PubMed

    Borochov-Neori, Hamutal; Judeinstein, Sylvie; Greenberg, Amnon; Volkova, Nina; Rosenblat, Mira; Aviram, Michael

    2015-04-01

    Date (Phoenix dactylifera L.) fruit phenolic-acid or flavonol fractions were examined in vitro for antioxidant and antiatherogenic properties. Two fractions of each subgroup were prepared from two date varieties, 'Amari' and 'Hallawi', by solid phase extraction on C18. The fractions were analyzed for phenolics composition by RP-HPLC and tested for ferric-reducing antioxidant power, free radical scavenging capacity, inhibition of Cu(2+)-induced LDL oxidation, and enhancement of HDL-mediated cholesterol efflux from macrophages. All four fractions exhibited variable capacities to reduce ferric ions, scavenge radicals, and inhibit LDL oxidation. Flavonol fractions were considerably better inhibitors of LDL oxidation compared to phenolic acid fractions, with IC50's of 9-31 nmol GAE mL(-1) compared to 85-116 nmol GAE mL(-1), respectively. Only the flavonol fractions stimulated cholesterol removal from macrophages. Within each subgroup, the levels of all the activities varied with fraction composition. The results demonstrated strong structure-activity relationships for date phenolics and identified date flavonols as potential antiatherogenic bioactives. PMID:25765921

  7. Genetic resources of the functional food, teramnus labialis (L.f.) spreng for improving seed number, flavonol content, oil %, and fatty acid compositions

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Teramnus labialis is used as food in India and has potential to be used as a functional food vegetable in the U.S.A. Photoperiod-sensitive T. labialis accessions were grown in the greenhouse from 2010 to 2011 and evaluated for flavonol content, oil %, and fatty acid compositions. Significant variati...

  8. Characterization of new glycolipid biosurfactants, tri-acylated mannosylerythritol lipids, produced by Pseudozyma yeasts.

    PubMed

    Fukuoka, Tokuma; Morita, Tomotake; Konishi, Masaaki; Imura, Tomohiro; Kitamoto, Dai

    2007-07-01

    Mannosylerythritol lipids (MELs) are glycolipid biosurfactants produced by Pseudozyma yeasts. They show not only the excellent interfacial properties but also versatile biochemical actions. In the course of MEL production from soybean oil by P. antarctica and P. rugulosa, some new extracellular glycolipids (more hydrophobic than the previously reported di-acylated MELs) were found in the culture medium. The most hydrophobic one was identified as 1-O-alka(e)noyl-4-O-[(4',6'-di-O-acetyl-2',3'-di-O-alka(e)noyl)-beta-D-mannopyranosyl]-D-erythritol, namely tri-acylated MEL. Others were tri-acylated MELs bearing only one acetyl group. The tri-acylated MEL could be prepared by the lipase-catalyzed esterification of a di-acylated MEL with oleic acid implying that the new glycolipids are synthesized from di-acylated MELs in the culture medium containing the residual fatty acids. PMID:17417694

  9. Active Site and Laminarin Binding in Glycoside Hydrolase Family 55*

    PubMed Central

    Bianchetti, Christopher M.; Takasuka, Taichi E.; Deutsch, Sam; Udell, Hannah S.; Yik, Eric J.; Bergeman, Lai F.; Fox, Brian G.

    2015-01-01

    The Carbohydrate Active Enzyme (CAZy) database indicates that glycoside hydrolase family 55 (GH55) contains both endo- and exo-β-1,3-glucanases. The founding structure in the GH55 is PcLam55A from the white rot fungus Phanerochaete chrysosporium (Ishida, T., Fushinobu, S., Kawai, R., Kitaoka, M., Igarashi, K., and Samejima, M. (2009) Crystal structure of glycoside hydrolase family 55 β-1,3-glucanase from the basidiomycete Phanerochaete chrysosporium. J. Biol. Chem. 284, 10100–10109). Here, we present high resolution crystal structures of bacterial SacteLam55A from the highly cellulolytic Streptomyces sp. SirexAA-E with bound substrates and product. These structures, along with mutagenesis and kinetic studies, implicate Glu-502 as the catalytic acid (as proposed earlier for Glu-663 in PcLam55A) and a proton relay network of four residues in activating water as the nucleophile. Further, a set of conserved aromatic residues that define the active site apparently enforce an exo-glucanase reactivity as demonstrated by exhaustive hydrolysis reactions with purified laminarioligosaccharides. Two additional aromatic residues that line the substrate-binding channel show substrate-dependent conformational flexibility that may promote processive reactivity of the bound oligosaccharide in the bacterial enzymes. Gene synthesis carried out on ∼30% of the GH55 family gave 34 active enzymes (19% functional coverage of the nonredundant members of GH55). These active enzymes reacted with only laminarin from a panel of 10 different soluble and insoluble polysaccharides and displayed a broad range of specific activities and optima for pH and temperature. Application of this experimental method provides a new, systematic way to annotate glycoside hydrolase phylogenetic space for functional properties. PMID:25752603

  10. A series of Ni(II)-flavonolate complexes as structural and functional ES (enzyme-substrate) models of the Ni(II)-containing quercetin 2,3-dioxygenase.

    PubMed

    Sun, Ying-Ji; Huang, Qian-Qian; Zhang, Jian-Jun

    2014-05-01

    Ni(II)-flavonolate complexes [Ni(II)L(R)(fla)] (L(R)H: 2-{[bis(pyridin-2-ylmethyl)amino]methyl}-p/m-R-benzoic acid, R: p-OMe (1), p-Me (2), m-Br (4) and m-NO2 (5), fla: flavonolate) were synthesized and characterized with relevance to structural and functional models for the ES (enzyme-substrate) adduct of the Ni(II)-containing quercetin 2,3-dioxygenase (2,3-QD). Their structures, spectroscopic features, redox properties and the reactivity toward molecular oxygen have been investigated. The complexes show a similar distorted octahedral structure and higher enzyme-type dioxygenation reactivity than other reported metal-flavonolate complexes in the oxidative O-heterocyclic ring-opening of the bound substrate flavonolate at lower temperature owing to the introduced carboxylate group in the supporting model ligands. The reaction rate shows first-order dependence on both of the complex and O2 and the second-order rate constant k fits a Hammett linear free energy relationship (ρ = -0.71) for the substituent group in the supporting model ligand L(R). The complexes exhibit substituent group dependent structures, properties and reactivity and there are some relationship among them, which could be ascribed to the electronic nature of the substituent group via the benzoate, Ni(II) ion and O(4)=C(27)-C(21)=C(22) "electron conduit". In a word, the stronger electron donating group could induce a smaller torsion angle, larger λ(max) and lower redox potential of the bound flavonolate, making a higher reactivity finally. This study is the first example of a series of structural and functional ES models of the Ni(II)-containing 2,3-QD, providing important insights into the structure-property-reactivity relationship, the electronic substituent effects and carboxylate effects on the enzymatic reactivity and the catalytic role of the Ni(II)-containing 2,3-QD.

  11. Bioactive Iridoid Glycosides from the Whole Plants of Rehmannia chingii.

    PubMed

    Liu, Yan-Fei; Shi, Guo-Ru; Wang, Xin; Zhang, Chun-Lei; Wang, Yan; Chen, Ruo-Yun; Yu, De-Quan

    2016-02-26

    Nine new iridoid glycosides, rehmachingiiosides A-I (1-9), together with 16 known analogues, were isolated from the whole plants of Rehmannia chingii. The structures of compounds 1-9 were elucidated on the basis of spectroscopic data analysis and from chemical evidence. Furthermore, in two vitro assays, compounds 5 and 10 showed an inhibitory effect on LPS-induced NO production with IC50 values of 2.5 and 7.3 μM, and compounds 4, 6, and 10-12 (when evaluated at 10 μM) exhibited evidence of hepatoprotective effects against APAP-induced HepG2 cell damage.

  12. Phenylpropanoid Glycosides from the Leaves of Ananas comosus.

    PubMed

    Chen, Wen-Hao; Huang, Xiao-Juan; Shu, Huo-Ming; Hui, Yang; Guo, Fei-Yan; Song, Xiao-Ping; Ji, Ming-Hui; Chen, Guang-Ying

    2015-12-01

    Two new phenylpropanoid glycosides, named β-D-(1-O-acetyl-3,6-O-diferuloyl) fructofuranosyl β-D-6'-O-acetylglucopyranoside (1) and β-D-(1-O-acetyl-3,6-O-diferuloyl) fructofuranosyl α-D-glucopyranoside (2), along with two known analogues (3-4) and four glycerides (5-8), were isolated from the EtOAc extract of the leaves of Ananas comosus. Their structures were elucidated on the basis of 1D- and 2D-NMR analyses, as well as HR-ESI-MS experiments. Compounds 1-4 showed significant antibacterial activities against Staphylococcus aureus and Escherichia coli.

  13. Three New Cytotoxic Polyhydroxysteroidal Glycosides from Starfish Craspidaster hesperus

    PubMed Central

    Kang, Jun-Xia; Kang, Yong-Feng; Han, Hua

    2016-01-01

    Three new polyhydroxysteroidal glycosides, hesperuside A (1), B (2), and C (3), as well as a known novaeguinoside A (4), were isolated from the ethanol extract of starfish Craspidaster hesperus collected from the South China Sea. Their structures were elucidated by extensive spectroscopic methods and chemical evidence. The compounds 1–3 present unprecedented carbohydrate chain 3-O-methyl-β-d-galactopyranose, which differ from each other in the side chains. These compounds exhibited cytotoxicity against human tumor cells BEL-7402, MOLT-4, and A-549 in vitro. PMID:27775561

  14. Two new glycosides from the fruits of Morinda citrifolia L.

    PubMed

    Hu, Ming-Xu; Zhang, Hong-Cai; Wang, Yu; Liu, Shu-Min; Liu, Li

    2012-01-01

    To study the chemical constituents of the fruits of noni (Morinda citrifolia L.), and find novel compounds, an n-butanol extract of the ethanol soluble fraction was subjected to repeated silica gel and ODS column chromatography and HPLC. Two new glycosides were isolated and their structures elucidated by NMR and HRFAB-MS spectrometry as (2E,4E,7Z)-deca-2,4,7-trienoate-2-O-β-D-glucopyranosyl-β-D-glucopyranoside and amyl-1-O-β-D-apio-furanosyl-1,6-O-β-D-glucopyranoside, respectively.

  15. Two new flavonoid glycosides from Semen Ziziphi Spinosae.

    PubMed

    Zhang, Lin; Xu, Zhi-Lin; Wu, Chun-Fu; Yang, Jing-Yu; Kano, Yoshihiro; Yuan, Dan

    2012-01-01

    Two novel flavonoid glycosides, 6"'-dihydrophaseoylspinosin (1) and 6″,6"'-diferuloylspinosin (2), were isolated from the MeOH extract of Semen Ziziphi Spinosae, together with six known flavonoids, isovitexin-2″-O-β-(6-O-E-feruloyl)glucopyranoside (3), spinosin (4), isospinosin (5), 6"'-feruloylspinosin (6), swertisin (7), and isovitexin-2″-O-β-d-glucopyranoside (8). The structures of 1 and 2 were elucidated by spectroscopic methods including UV, IR, ESI-TOF-MS, 1D NMR, and 2D NMR experiments. PMID:22296152

  16. Flavonoid Glycosides from Arnica montana and Arnica chamissonis.

    PubMed

    Merfort, I; Wendisch, D

    1987-10-01

    Five flavonoid glycosides were identified from flowers of ARNICA MONTANA, four from A. CHAMISSONIS subsp. FOLIOSA var. INCANA. The structures were established on the basis of total acid hydrolysis and spectral data (UV, (1)H-NMR, (13)C-NMR, MS) as hispidulin 7- O-beta-glucoside, isorhamnetin 3- O-beta-glucoside, 3- O-beta- D-glucopyranosides of spinacetin, 6-methoxykaempferol and patuletin and querectin 3- O-(6''- O-acetyl)-beta- D-glucopyranoside. The latter compound can serve as distinctive marker between these two ARNICA species. The (1)H-NMR spectra in CD (3)OD are discussed.

  17. A novel sulfated holostane glycoside from sea cucumber Holothuria leucospilota.

    PubMed

    Han, Hua; Zhang, Wen; Yi, Yang-Hua; Liu, Bao-Shu; Pan, Min-Xiang; Wang, Xiao-Hua

    2010-07-01

    A new sulfated holostane glycoside, leucospilotaside B (1), together with the two related structurally known compounds holothurin B(2) (2) and holothurin B (3), was isolated from sea cucumber Holothuria leucospilota collected from the South China Sea. The structure of 1 was elucidated by spectral analysis (1H-, 13C-, and 2D-NMR, ESI-MS, and HR-ESI-MS) and chemical methods. The compounds 1-3 possess the same disaccharide moiety, but were different in the side chains of the triterpene aglycone. Compound 1 showed significant cytotoxicities against four human tumor cell lines, HL-60, MOLT-4, A-549, and BEL-7402.

  18. Effects of temperature and photoperiod on sensory quality and contents of glucosinolates, flavonols and vitamin C in broccoli florets.

    PubMed

    Mølmann, Jørgen A B; Steindal, Anne L H; Bengtsson, Gunnar B; Seljåsen, Randi; Lea, Per; Skaret, Josefine; Johansen, Tor J

    2015-04-01

    Broccoli is grown around the world at a wide range of photoperiods and temperatures, which may influence both sensory quality and phytochemical contents. Florets produced in phytotron and at two semi-field sites (70 °N and 58 °N) were examined for effects of contrasting temperatures and photoperiods on sensory quality and contents of glucosinolates, flavonols and vitamin C. Growth conditions associated with high northern latitudes of low temperature and long photoperiods, produced bigger floral buds, and florets with sweeter taste and less colour hue than more southern conditions. The contents of vitamin C did not vary, while the response of individual glucosinolates varied with temperature and day length, and contents of quercetin and kaempferol were lower in phytotron than under semi-field conditions. Thus, our results show that contrasting temperatures and photoperiods influence the sensory quality of broccoli florets, while contents of different bioactive phytochemicals are not influenced in a unidirectional pattern.

  19. [Full-length cDNA cloning of flavonol synthase genes of Carthamus tinctorius and construction plant expression vector].

    PubMed

    Yang, Wen-ting; Liu, Xiu-ming; Wan, Qiu; Yao, Na; Wang, Nan; Zhang, Xue-meng; Jiao, Zhong-da; Li, Hai-yan; Li, Xiao-kun

    2015-02-01

    Flavonol synthase (FLS) is one of the key enzymes in flavonoids metabolic pathways. In this study, middle sequence was obtained from Carthamus tinctorius transcriptome sequencing results. Full-length cDNAs of FLS was cloned from petals of C. tinctorius to FLS by using RT-PCR and RACE technology. Its full-length cDNA was 1,201 bp, with an open reading frame of 1,101 bp and 336 encoded amino acids. The phylogenetic analysis showed that, FLS gene encoded amino acids in C. tinctorius were highly homologous with amino acids in congeneric Compositae species, especially Rudbeckia laciniata. The pBASTA-FLS plant expression vector was successfully built by the molecular biology method, which lays a foundation for further studying biology functions of the gene and biosynthesis mechanism of flavonoids.

  20. A novel insulin mimetic vanadium-flavonol complex: synthesis, characterization and in vivo evaluation in STZ-induced rats.

    PubMed

    Pillai, Subramanian Iyyam; Subramanian, Sorimuthu Pillai; Kandaswamy, Muthusamy

    2013-05-01

    Since 1985, when Heyliger et al., first demonstrated a serendipitous discovery that oral administration of 0.8 mg/ml of sodium orthovanadate in drinking water to streptozotocin-induced diabetic rats resulted in normoglycemia, numerous extensive studies have been pursued on the anti-diabetic and insulinomimetic actions of vanadium. The acceptance of vanadium compounds as promising therapeutic antidiabetic agents has been slowed due to the concern for chronic toxicity associated with vanadium accumulation. In order to circumvent the toxic effects of vanadium, we have taken up a combinational approach wherein a novel vanadium-flavonol complex was synthesized, characterized and its toxic as well as insulin mimetic potential was evaluated in STZ-induced experimental diabetes in rats. The results indicate that the complex is non-toxic and possess anti-diabetic activity.

  1. Two new nor-triterpene glycosides from peruvian "Uña de Gato" (Uncaria tomentosa).

    PubMed

    Kitajima, Mariko; Hashimoto, Ken-Ichiro; Yokoya, Masashi; Takayama, Hiromitsu; Sandoval, Manuel; Aimi, Norio

    2003-02-01

    Two new 27-nor-triterpene glycosides, tomentosides A (1) and B (2), were isolated from Peruvian "Uña de Gato" (cat's claw, plant of origin: Uncaria tomentosa), a traditional herbal medicine in Peru. Their structures were determined by spectroscopic analysis and chemical interconversions. This is the first report of naturally occurring pyroquinovic acid glycosides.

  2. Two new nor-triterpene glycosides from peruvian "Uña de Gato" (Uncaria tomentosa).

    PubMed

    Kitajima, Mariko; Hashimoto, Ken-Ichiro; Yokoya, Masashi; Takayama, Hiromitsu; Sandoval, Manuel; Aimi, Norio

    2003-02-01

    Two new 27-nor-triterpene glycosides, tomentosides A (1) and B (2), were isolated from Peruvian "Uña de Gato" (cat's claw, plant of origin: Uncaria tomentosa), a traditional herbal medicine in Peru. Their structures were determined by spectroscopic analysis and chemical interconversions. This is the first report of naturally occurring pyroquinovic acid glycosides. PMID:12608878

  3. Species and ionic influences on the accumulation of digitalis glycosides by isolated perfused hearts

    PubMed Central

    Dutta, S.; Marks, B. H.

    1972-01-01

    1. The ability of isolated perfused guinea-pig (digitalis-sensitive species) and rat (digitalis-resistant species) hearts to accumulate radio-labelled digitalis glycosides was studied in relation to the ionic composition of the perfusion medium. 2. It was observed that in both species much less digoxin was accumulated than was digitoxin or proscillaridin. 3. The accumulation of digoxin was markedly inhibited in a low sodium or in high potassium medium. These effects were similar, but relatively less marked, with digitoxin and proscillaridin. Calcium and magnesium removal had relatively smaller effects on the accumulation of both polar and non-polar glycosides. 4. The low accumulation of all digitaloids by the rat heart in comparison to the guinea-pig heart may be due to the formation of unstable complexes between the cellular membranes in the rat heart and the various digitaloids used in this study. Although digitaloids have a reduced affinity for rat hearts and rat heart membranes in comparison to guinea-pigs, the order of the accumulation of different glycosides in both species is the same, i.e. much less with polar glycosides than with non-polar glycosides. 5. It was concluded that non-polar glycosides such as digitoxin and proscillaridin demonstrate the same ion-dependent accumulation mechanism as do the more polar glycosides such as digoxin and ouabain. In addition, the non-polar glycosides possess high capacity for ion-independent binding presumably due to lipophilic interactions with membranes. PMID:4656603

  4. Bebrycoside, a new steroidal glycoside from the Chinese gorgonian coral Bebryce indica.

    PubMed

    Yang, Jin; Qi, Shu-Hua; Zhang, Si; Xiao, Zhi-Hui; Li, Qing-Xin

    2007-02-01

    A new steroidal glycoside, bebrycoside (1), was isolated from the South China Sea gorgonian coral Bebryce indica. The structure of 1 was established by extensive spectroscopic analysis, including 1D and 2D NMR data. This was the first time that the steroidal glycoside was isolated from the genus of Bebryce.

  5. Complete assignments of 1H and 13C NMR data for 10 phenylethanoid glycosides.

    PubMed

    Wu, Jun; Huang, Jianshe; Xiao, Qiang; Zhang, Si; Xiao, Zhihui; Li, Qingxin; Long, Lijuan; Huang, Liangmin

    2004-07-01

    Ten phenylethanoid glycosides, including two new ones, isolated from the aerial parts of the mangrove plant Acanthus ilicifolius were identified. The first complete assignments of the 1H and 13C NMR chemical shifts for these glycosides were achieved by means of 2D NMR techniques, including 1H-1H COSY, TOCSY, HSQC and HMBC spectra.

  6. Host plant influences on iridoid glycoside sequestration of generalist and specialist caterpillars.

    PubMed

    Lampert, Evan C; Bowers, M Deane

    2010-10-01

    The effect of diet on sequestration of iridoid glycosides was examined in larvae of three lepidopteran species. Larvae were reared upon Plantago major, or P. lanceolata, or switched from one to the other in the penultimate instar. Junonia coenia is a specialist on iridoid glycoside-producing plants, whereas the arctiids, Spilosoma congrua and Estigmene acrea, are both polyphagous and eat iridoid-producing plants. All species sequestered iridoids. The specialist J. coenia sequestered from three to seven times the amounts sequestered by the two generalist species. Junonia coenia iridoid glycoside content depended on diet, and they sequestered from 5 to 15% dry weight iridoid glycosides. Estigmene acrea iridoid glycoside sequestration was relatively low, around 2% dry weight and did not vary with diet. Spilosoma congrua sequestration varied with diet and ranged from approximately 3 to 6% dry weight. PMID:20809144

  7. Merremins A-G, resin glycosides from Merremia hederacea with multidrug resistance reversal activity.

    PubMed

    Wang, Wen-qiong; Song, Wei-bin; Lan, Xiao-jing; Huang, Min; Xuan, Li-jiang

    2014-10-24

    Five new pentasaccharide resin glycosides, named merremins A-E (1-5), two new pentasaccharide resin glycoside methyl esters, named merremins F and G (6, 7), and four known resin glycosides, murucoidin IV, murucoidin V, stoloniferin IV, and murucoidin XVII, were obtained from the aerial parts of Merremia hederacea. This is the first report of resin glycosides obtained from M. hederacea. In addition, the new compounds can be divided into three types: those possessing an 18-membered ring (1-4), compound 5 with a 20-membered ring, and those with an acyclic core (6, 7). Furthermore, the different types of resin glycosides were evaluated for their multidrug resistance reversal activities. Compounds 1, 5, 6, and murucoidin V were noncytotoxic and enhanced the cytotoxicity of vinblastine by 2.3-142.5-fold at 25 μM. Compound 5 and murucoidin V, with 20-membered rings, were more active than compound 1, with an 18-membered ring.

  8. Mass spectrometric imaging of flavonoid glycosides and biflavonoids in Ginkgo biloba L.

    PubMed

    Beck, Sebastian; Stengel, Julia

    2016-10-01

    Ginkgo biloba L. is known to be rich in flavonoids and flavonoid glycosides. However, the distribution within specific plant organs (e.g. within leaves) is not known. By using HPLC-MS and MS/MS we have identified a number of previously known G. biloba flavonoid glycosides and biflavonoids from leaves. Namely, kaempferol, quercetin, isorhamnetin, myricetin, laricitrin/mearnsetin and apigenin glycosides were identified. Furthermore, biflavonoids like ginkgetin/isoginkgetin were also detected. The application of MALDI mass spectrometric imaging, enabled the compilation of concentration profiles of flavonoid glycosides and biflavonoids in G. biloba L. leaves. Both, flavonoid glycosides and biflavonoids show a distinct distribution in leaf thin sections of G. biloba L. PMID:27233155

  9. Mass spectrometric imaging of flavonoid glycosides and biflavonoids in Ginkgo biloba L.

    PubMed

    Beck, Sebastian; Stengel, Julia

    2016-10-01

    Ginkgo biloba L. is known to be rich in flavonoids and flavonoid glycosides. However, the distribution within specific plant organs (e.g. within leaves) is not known. By using HPLC-MS and MS/MS we have identified a number of previously known G. biloba flavonoid glycosides and biflavonoids from leaves. Namely, kaempferol, quercetin, isorhamnetin, myricetin, laricitrin/mearnsetin and apigenin glycosides were identified. Furthermore, biflavonoids like ginkgetin/isoginkgetin were also detected. The application of MALDI mass spectrometric imaging, enabled the compilation of concentration profiles of flavonoid glycosides and biflavonoids in G. biloba L. leaves. Both, flavonoid glycosides and biflavonoids show a distinct distribution in leaf thin sections of G. biloba L.

  10. Quantitation of sweet steviol glycosides by means of a HILIC-MS/MS-SIDA approach.

    PubMed

    Well, Caroline; Frank, Oliver; Hofmann, Thomas

    2013-11-27

    Meeting the rising consumer demand for natural food ingredients, steviol glycosides, the sweet principle of Stevia rebaudiana Bertoni (Bertoni), have recently been approved as food additives in the European Union. As regulatory constraints require sensitive methods to analyze the sweet-tasting steviol glycosides in foods and beverages, a HILIC-MS/MS method was developed enabling the accurate and reliable quantitation of the major steviol glycosides stevioside, rebaudiosides A-F, steviolbioside, rubusoside, and dulcoside A by using the corresponding deuterated 16,17-dihydrosteviol glycosides as suitable internal standards. This quantitation not only enables the analysis of the individual steviol glycosides in foods and beverages but also can support the optimization of breeding and postharvest downstream processing of Stevia plants to produce preferentially sweet and least bitter tasting Stevia extracts.

  11. New Glycosides and Trypanocidal Metabolites from Vangueria edulis

    PubMed Central

    Mohamed, Shaymaa M. M.; Elokely, Khaled M.; Bachkeet, Enaam Y.; Bayoumi, Soad A. L.; Carnevale, Vincenzo; Klein, Michael L.; Cutler, Stephen J.

    2016-01-01

    A new iridoid glucoside, 10-methoxy apodanthoside (1), and a new monoterpene glycoside, (3S,6S)-cis linalool-3,7-oxide O-β-D-glucopyranosyl-(1″→5′)-β-D-xylofuranoside (2), were isolated from V. edulis (Rubiaceae), along with eighteen known compounds (3–20), including monoterpenes, iridoid glycosides, and a lignin, which were encountered for the first time in the genus Vangueria,. The structural elucidation of the isolates was based on the analysis of spectroscopic (1D and 2D NMR) and HR-ESI-MS data. Detailed stereochemical studies of 1 and related iridoid glucosides (compounds 3, 4 and 8) were made by matching the calculated ECD peaks with the experimental ones. All isolates were tested for their antiprotozoal, antifungal, and antiplasmodial activities. Compounds 9, 15 and 16 showed good trypanocidal activities against Trypanosoma brucei brucei with IC50 values of 8.18, 9.02 and 7.80 μg/mL, respectively and IC90 values of >10, >10 and 9.76 μg/mL, respectively. Compound 16 showed a moderate activity against Candida glabrata with an IC50 value of 8.66 μg/mL. Compound 20 showed a weak antiplasmodial activity against chloroquine-sensitive (D6) and resistant (W2) Plasmodium falciparum with IC50 values of 3.29 (SI, >1.4) and 4.53 (SI, >1) μg/mL, respectively. PMID:26749819

  12. Separation of phenylpropanoid glycosides from a Chinese herb by HSCCC.

    PubMed

    Chen, Chen; Zhao, Xiao-Hui; Yue, Hui-Lan; Li, Yu-Lin; Chen, Tao

    2014-01-01

    An effective high-speed counter-current chromatography method was established for the preparative isolation and purification of two phenylpropanoid glycosides from the Tibetan medicinal plant Pedicularis longiflora Rudolph. var. tubiformis (Klotz). Tsoong. With a two-phase solvent system composed of chloroform-n-butanol-methanol-water (4:3:4:5, v/v), 40 mg of an extract of Pedicularis longiflora Rudolph. var. tubiformis (Klotz). Tsoong was separated to yield 20 mg of verbascoside and 18 mg of isoacteoside, with purity values of 97 and 98%, respectively. The chemical structures of these two components were identified by proton and carbon nuclear magnetic resonance. In addition, the antioxidant activity of the two phenylpropanoid glycosides was evaluated by 2,2-diphenyl-1-picrylhydrazyl (DPPH)-high-performance liquid chromatography, and the results showed that the two components exhibited strong antioxidant DPPH radical scavenging activity, with IC50 values of 15.6 and 18.9 µg/mL, respectively.

  13. Steviol Glycosides Modulate Glucose Transport in Different Cell Types

    PubMed Central

    Rizzo, Benedetta; Zambonin, Laura; Leoncini, Emanuela; Vieceli Dalla Sega, Francesco; Prata, Cecilia; Fiorentini, Diana; Hrelia, Silvana

    2013-01-01

    Extracts from Stevia rebaudiana Bertoni, a plant native to Central and South America, have been used as a sweetener since ancient times. Currently, Stevia extracts are largely used as a noncaloric high-potency biosweetener alternative to sugar, due to the growing incidence of type 2 diabetes mellitus, obesity, and metabolic disorders worldwide. Despite the large number of studies on Stevia and steviol glycosides in vivo, little is reported concerning the cellular and molecular mechanisms underpinning the beneficial effects on human health. The effect of four commercial Stevia extracts on glucose transport activity was evaluated in HL-60 human leukaemia and in SH-SY5Y human neuroblastoma cells. The extracts were able to enhance glucose uptake in both cellular lines, as efficiently as insulin. Our data suggest that steviol glycosides could act by modulating GLUT translocation through the PI3K/Akt pathway since treatments with both insulin and Stevia extracts increased the phosphorylation of PI3K and Akt. Furthermore, Stevia extracts were able to revert the effect of the reduction of glucose uptake caused by methylglyoxal, an inhibitor of the insulin receptor/PI3K/Akt pathway. These results corroborate the hypothesis that Stevia extracts could mimic insulin effects modulating PI3K/Akt pathway. PMID:24327825

  14. Anti HIV-1 flavonoid glycosides from Ochna integerrima.

    PubMed

    Reutrakul, Vichai; Ningnuek, Niwat; Pohmakotr, Manat; Yoosook, Chalobon; Napaswad, Chanita; Kasisit, Jitra; Santisuk, Thawatchai; Tuchinda, Patoomratana

    2007-06-01

    Bioassay-guided fractionation of the anti-HIV-1 active EtOAc extract from leaves and twigs of Ochna integerrima led to the isolation of five new flavonoid glycosides 1 - 5, five known flavonoids 6 - 10, and two known flavonoid glycosides 11 and 12. Structures were determined based on spectroscopic analyses. 6- gamma, gamma-Dimethylallyldihydrokaempferol 7- O- beta-D-glucoside (1), 6-gamma, gamma-dimethylallylquercetin 7- O- beta- D-glucoside (3), 6-(3-hydroxy-3-methylbutyl)taxifolin 7- O- beta-D-glucoside (4), 6-(3-hydroxy-3-methylbutyl)quercetin 7- O-beta-D-glucoside (5), and 6-gamma, gamma-dimethylallyltaxifolin 7-O-beta-D-glucoside (11) showed anti-HIV-1 activities in the syncytium assay using the (Delta Tat/rev)MC99 virus and the 1A2 cell line system with EC(50) values ranging from 14.0 - 102.4 microg/mL. Furthermore, ochnaflavone 7''-O-methyl ether (7) and 2'', 3''-dihydroochnaflavone 7''-O-methyl ether (8) were very active; they exerted activities in the syncytium assay with EC(50) values of 2.0 and 0.9 microg/mL, respectively, and likewise inhibited HIV-1 reverse transcriptase (RT) with IC(50) values of 2.0 and 2.4 microg/mL, respectively.

  15. A new glycosidic flavonoid from Jwarhar mahakashay (antipyretic) Ayurvedic preparation

    PubMed Central

    Gupta, Mradu; Shaw, B. P.; Mukherjee, A.

    2010-01-01

    The aqueous extract of Jwarhar mahakashay Ayurvedic preparation (from the roots of Hemidesmus indicus R. Br., Rubia cordifolia L., Cissampelos pareira L.; fruits of Terminalia chebula Retz., Emblica officinalis Gaertn., Terminalia bellirica Roxb., Vitis vinifera L., Grewia asiatica L., Salvadora persica L. and granules of Saccharum officinarum L.) has been used as a traditional antipyretic. Experimental studies confirmed its antipyretic–analgesic effect with very low ulcerogenicity and toxicity. Flavonoids, glycosides and tannins were later found to be present in the extract. Detailed chemical investigations were undertaken after hydrolysis of extract using spectroscopic and chromatography methods to determine its active chemical constituent. UV-Visible spectroscopy showed absorbance maxima at 220 and 276 nm, while fourier transform infra-red investigations indicated an end carboxylic O–H structure at 2940 cm−1 suggesting the presence of glycoside-linked flavonoids. Thin layer chromatography and high performance liquid chromatography also confirmed the possibility of at least one major and two minor compounds in this abstract. Detailed examination using gas chromatography-mass spectrometry led to the identification of the principal component as 2-(1-oxopropyl)-benzoic acid, which is quite similar to the active compound found in the standard drug Aspirin (2-acetyl-oxybenzoic acid). PMID:20814525

  16. Cycloartane and oleanane-type glycosides from Astragalus pennatulus.

    PubMed

    Un, Rabia; Horo, Ibrahim; Masullo, Milena; Falco, Antonia; Senol, Serdar G; Piacente, Sonia; Alankuş-Çalıskan, Özgen

    2016-03-01

    Four new cycloartane and one new oleanane-type glycosides were isolated from Astragalus pennatulus along with five known cycloartane-type glycosides. The structures of the new compounds were established as 3-O-β-D-xylopyranosyl-6-O-β-D-glucopyranosyl-3β,6α,16β-trihydroxy-24-oxo-20(R),25-epoxycycloartane (1), 3-O-[β-D-glucuronopyranosyl-(1 → 2)-β-D-xylopyranosyl]-3β,16β,24α-trihydroxy-20(R),25-epoxycycloartane (2), 3-O-[β-D-glucuronopyranosyl-(1 → 2)-β-D-xylopyranosyl]-3β,16β,25-trihydroxy-20(R),24(S)-epoxycycloartane (3), 3,25-di-O-β-D-glucopyranosyl-6-O-β-D-xylopyranosyl-3β,6α,16β,25-tetrahydroxy-20(R),24(S)-epoxycycloartane (4), 29-O-α-L-rhamnopyranosyl-abrisapogenol B (5) by 1D and 2D-NMR experiments along with ESIMS and HRMS analyses. The aglycone of compound 1, 3β,6α,16β-trihydroxy-24-oxo-20(R),25-epoxycycloartane, is reported for the first time. The cytotoxic activity of the isolated compounds was evaluated against three cancer cell lines including A549 (human lung adenocarcinoma), A375 (human melanoma) and DeFew (human B lymphoma) cells. None of the tested compounds caused a significant reduction of the cell number. PMID:26804373

  17. Recovering glycoside hydrolase genes from active tundra cellulolytic bacteria.

    PubMed

    Pinnell, Lee J; Dunford, Eric; Ronan, Patrick; Hausner, Martina; Neufeld, Josh D

    2014-07-01

    Bacteria responsible for cellulose hydrolysis in situ are poorly understood, largely because of the relatively recent development of cultivation-independent methods for their detection and characterization. This study combined DNA stable-isotope probing (DNA-SIP) and metagenomics for identifying active bacterial communities that assimilated carbon from glucose and cellulose in Arctic tundra microcosms. Following DNA-SIP, bacterial fingerprint analysis of gradient fractions confirmed isotopic enrichment. Sequenced fingerprint bands and clone library analysis of 16S rRNA genes identified active bacterial taxa associated with cellulose-associated labelled DNA, including Bacteroidetes (Sphingobacteriales), Betaproteobacteria (Burkholderiales), Alphaproteobacteria (Caulobacteraceae), and Chloroflexi (Anaerolineaceae). We also compared glycoside hydrolase metagenomic profiles from bulk soil and heavy DNA recovered from DNA-SIP incubations. Active populations consuming [(13)C]glucose and [(13)C]cellulose were distinct, based on ordinations of light and heavy DNA. Metagenomic analysis demonstrated a ∼3-fold increase in the relative abundance of glycoside hydrolases in DNA-SIP libraries over bulk-soil libraries. The data also indicate that multiple displacement amplification introduced bias into the resulting metagenomic analysis. This research identified DNA-SIP incubation conditions for glucose and cellulose that were suitable for Arctic tundra soil and confirmed that DNA-SIP enrichment can increase target gene frequencies in metagenomic libraries.

  18. Synthesis of Indoxyl-glycosides for Detection of Glycosidase Activities.

    PubMed

    Böttcher, Stephan; Thiem, Joachim

    2015-01-01

    Indoxyl glycosides proved to be valuable and versatile tools for monitoring glycosidase activities. Indoxyls are released by enzymatic hydrolysis and are rapidly oxidized, for example by atmospheric oxygen, to indigo type dyes. This reaction enables fast and easy screening in vivo without isolation or purification of enzymes, as well as rapid tests on agar plates or in solution (e.g., blue-white screening, micro-wells) and is used in biochemistry, histochemistry, bacteriology and molecular biology. Unfortunately the synthesis of such substrates proved to be difficult, due to various side reactions and the low reactivity of the indoxyl hydroxyl function. Especially for glucose type structures low yields were observed. Our novel approach employs indoxylic acid ester as key intermediates. Indoxylic acid esters with varied substitution patterns were prepared on scalable pathways. Phase transfer glycosylations with those acceptors and peracetylated glycosyl halides can be performed under common conditions in high yields. Ester cleavage and subsequent mild silver mediated glycosylation yields the peracetylated indoxyl glycosides in high yields. Finally deprotection is performed according to Zemplén. PMID:26068577

  19. Tissue factor inhibitory sesquiterpene glycoside from Eriobotrya japonica.

    PubMed

    Lee, Ming Hong; Son, Yeon Kyoung; Han, Yong Nam

    2004-06-01

    Tissue factor (TF, tissue thromboplastin) is a membrane bound glycoprotein, which accelerates the blood clotting, activating both the intrinsic and the extrinsic pathways to serve as a cofactor for activated factor VII (VIIa). The TF-factor VIIa complex (TF/VIIa) proteolytically activates factors IX and X, which leads to the generation of thrombin and fibrin clots. In order to isolate TF inhibitors, by means of a bioassay-directed chromatographic separation technique, from the leaves of Eriobotrya japonica Lindley (Rosaceae), a known sesquiterpene glycoside (2) and ferulic acid (3) were isolated as inhibitors that were evaluated using a single-clotting assay method for determining TF activity. Another sesquiterpene glycoside (1) was also isolated but was inactive in the assay system. Compound 3 was yielded by alkaline hydrolysis of compound 2. The structures of compounds 1, 2, and 3 were identified by means of spectral analysis as 3-O-alpha-L-rhamnopyranosyl-(1-->4)-alpha-L-rhamnopyranosyl-(1-->2)-[alpha-L-rhamnopyranosyl-(1-->6)]-beta-D-glucopyranosyl nerolidol (1), 3-O-alpha-L-rhamnopyranosyl-(1-->4)-alpha-L-rhamnopyranosyl-(1-->2)-[alpha-L-(4-trans-feruloyl)-rhamnopyranosyl-(1-->6)]-beta-D-glucopyranosyl nerolidol (2) and ferulic acid (3), respectively. Compounds 2 and 3 inhibited 50% of the TF activity at concentrations of 2 and 369 microM/TF units, respectively.

  20. Cycloartane and oleanane-type glycosides from Astragalus pennatulus.

    PubMed

    Un, Rabia; Horo, Ibrahim; Masullo, Milena; Falco, Antonia; Senol, Serdar G; Piacente, Sonia; Alankuş-Çalıskan, Özgen

    2016-03-01

    Four new cycloartane and one new oleanane-type glycosides were isolated from Astragalus pennatulus along with five known cycloartane-type glycosides. The structures of the new compounds were established as 3-O-β-D-xylopyranosyl-6-O-β-D-glucopyranosyl-3β,6α,16β-trihydroxy-24-oxo-20(R),25-epoxycycloartane (1), 3-O-[β-D-glucuronopyranosyl-(1 → 2)-β-D-xylopyranosyl]-3β,16β,24α-trihydroxy-20(R),25-epoxycycloartane (2), 3-O-[β-D-glucuronopyranosyl-(1 → 2)-β-D-xylopyranosyl]-3β,16β,25-trihydroxy-20(R),24(S)-epoxycycloartane (3), 3,25-di-O-β-D-glucopyranosyl-6-O-β-D-xylopyranosyl-3β,6α,16β,25-tetrahydroxy-20(R),24(S)-epoxycycloartane (4), 29-O-α-L-rhamnopyranosyl-abrisapogenol B (5) by 1D and 2D-NMR experiments along with ESIMS and HRMS analyses. The aglycone of compound 1, 3β,6α,16β-trihydroxy-24-oxo-20(R),25-epoxycycloartane, is reported for the first time. The cytotoxic activity of the isolated compounds was evaluated against three cancer cell lines including A549 (human lung adenocarcinoma), A375 (human melanoma) and DeFew (human B lymphoma) cells. None of the tested compounds caused a significant reduction of the cell number.

  1. Flacourtosides A-F, phenolic glycosides isolated from Flacourtia ramontchi.

    PubMed

    Bourjot, Mélanie; Leyssen, Pieter; Eydoux, Cécilia; Guillemot, Jean-Claude; Canard, Bruno; Rasoanaivo, Philippe; Guéritte, Françoise; Litaudon, Marc

    2012-04-27

    In an effort to identify novel inhibitors of chikungunya (CHIKV) and dengue (DENV) virus replication, a systematic study with 820 ethyl acetate extracts of madagascan plants was performed in a virus-cell-based assay for CHIKV, and a DENV NS5 RNA-dependent RNA polymerase (RdRp) assay. The extract obtained from the stem bark of Flacourtia ramontchi was selected for its significant activity in both assays. Six new phenolic glycosides, named flacourtosides A-F (1-6), phenolic glycosides itoside H, xylosmin, scolochinenoside D, and poliothrysoside, and betulinic acid 3β-caffeate were obtained using the bioassay-guided isolation process. Their structures were elucidated by comprehensive analyses of NMR spectroscopic and mass spectrometric data. Even though several extracts and fractions showed significant selective antiviral activity in the CHIKV virus-cell-based assay, none of the purified compounds did. However, in the DENV RNA polymerase assay, significant inhibition was observed with betulinic acid 3β-caffeate (IC(50) = 0.85 ± 0.1 μM) and to a lesser extent for the flacourtosides A and E (1 and 5, respectively), and scolochinenoside D (IC(50) values ~10 μM). PMID:22439591

  2. Acyl-Protein Thioesterase 2 Catalizes the Deacylation of Peripheral Membrane-Associated GAP-43

    PubMed Central

    Tomatis, Vanesa M.; Trenchi, Alejandra; Gomez, Guillermo A.; Daniotti, Jose L.

    2010-01-01

    An acylation/deacylation cycle is necessary to maintain the steady-state subcellular distribution and biological activity of S-acylated peripheral proteins. Despite the progress that has been made in identifying and characterizing palmitoyltransferases (PATs), much less is known about the thioesterases involved in protein deacylation. In this work, we investigated the deacylation of growth-associated protein-43 (GAP-43), a dually acylated protein at cysteine residues 3 and 4. Using fluorescent fusion constructs, we measured in vivo the rate of deacylation of GAP-43 and its single acylated mutants in Chinese hamster ovary (CHO)-K1 and human HeLa cells. Biochemical and live cell imaging experiments demonstrated that single acylated mutants were completely deacylated with similar kinetic in both cell types. By RT-PCR we observed that acyl-protein thioesterase 1 (APT-1), the only bona fide thioesterase shown to mediate deacylation in vivo, is expressed in HeLa cells, but not in CHO-K1 cells. However, APT-1 overexpression neither increased the deacylation rate of single acylated GAP-43 nor affected the steady-state subcellular distribution of dually acylated GAP-43 both in CHO-K1 and HeLa cells, indicating that GAP-43 deacylation is not mediated by APT-1. Accordingly, we performed a bioinformatic search to identify putative candidates with acyl-protein thioesterase activity. Among several candidates, we found that APT-2 is expressed both in CHO-K1 and HeLa cells and its overexpression increased the deacylation rate of single acylated GAP-43 and affected the steady-state localization of diacylated GAP-43 and H-Ras. Thus, the results demonstrate that APT-2 is the protein thioesterase involved in the acylation/deacylation cycle operating in GAP-43 subcellular distribution. PMID:21152083

  3. Small-molecule inhibitor binding to an N-acyl-homoserine lactone synthase.

    PubMed

    Chung, Jiwoung; Goo, Eunhye; Yu, Sangheon; Choi, Okhee; Lee, Jeehyun; Kim, Jinwoo; Kim, Hongsup; Igarashi, Jun; Suga, Hiroaki; Moon, Jae Sun; Hwang, Ingyu; Rhee, Sangkee

    2011-07-19

    Quorum sensing (QS) controls certain behaviors of bacteria in response to population density. In gram-negative bacteria, QS is often mediated by N-acyl-L-homoserine lactones (acyl-HSLs). Because QS influences the virulence of many pathogenic bacteria, synthetic inhibitors of acyl-HSL synthases might be useful therapeutically for controlling pathogens. However, rational design of a potent QS antagonist has been thwarted by the lack of information concerning the binding interactions between acyl-HSL synthases and their ligands. In the gram-negative bacterium Burkholderia glumae, QS controls virulence, motility, and protein secretion and is mediated by the binding of N-octanoyl-L-HSL (C8-HSL) to its cognate receptor, TofR. C8-HSL is synthesized by the acyl-HSL synthase TofI. In this study, we characterized two previously unknown QS inhibitors identified in a focused library of acyl-HSL analogs. Our functional and X-ray crystal structure analyses show that the first inhibitor, J8-C8, binds to TofI, occupying the binding site for the acyl chain of the TofI cognate substrate, acylated acyl-carrier protein. Moreover, the reaction byproduct, 5'-methylthioadenosine, independently binds to the binding site for a second substrate, S-adenosyl-L-methionine. Closer inspection of the mode of J8-C8 binding to TofI provides a likely molecular basis for the various substrate specificities of acyl-HSL synthases. The second inhibitor, E9C-3oxoC6, competitively inhibits C8-HSL binding to TofR. Our analysis of the binding of an inhibitor and a reaction byproduct to an acyl-HSL synthase may facilitate the design of a new class of QS-inhibiting therapeutic agents.

  4. Identification and quantification of glucosinolate and flavonol compounds in rocket salad (Eruca sativa, Eruca vesicaria and Diplotaxis tenuifolia) by LC-MS: highlighting the potential for improving nutritional value of rocket crops.

    PubMed

    Bell, Luke; Oruna-Concha, Maria Jose; Wagstaff, Carol

    2015-04-01

    Liquid chromatography mass spectrometry (LC-MS) was used to obtain glucosinolate and flavonol content for 35 rocket accessions and commercial varieties. 13 glucosinolates and 11 flavonol compounds were identified. Semi-quantitative methods were used to estimate concentrations of both groups of compounds. Minor glucosinolate composition was found to be different between accessions; concentrations varied significantly. Flavonols showed differentiation between genera, with Diplotaxis accumulating quercetin glucosides and Eruca accumulating kaempferol glucosides. Several compounds were detected in each genus that have only previously been reported in the other. We highlight how knowledge of phytochemical content and concentration can be used to breed new, nutritionally superior varieties. We also demonstrate the effects of controlled environment conditions on the accumulations of glucosinolates and flavonols and explore the reasons for differences with previous studies. We stress the importance of consistent experimental design between research groups to effectively compare and contrast results.

  5. Acylation of Antioxidant of Bamboo Leaves with Fatty Acids by Lipase and the Acylated Derivatives' Efficiency in the Inhibition of Acrylamide Formation in Fried Potato Crisps.

    PubMed

    Ma, Xiang; Wang, Erpei; Lu, Yuyun; Wang, Yong; Ou, Shiyi; Yan, Rian

    2015-01-01

    This study selectively acylated the primary hydroxyl groups on flavonoids in antioxidant of bamboo leaves (AOB) using lauric acid with Candida antarctica lipase B in tert-amyl-alcohol. The separation and isolation of acylated derivatives were performed using silica gel column chromatography with a mixture of dichloromethane/diethyl ether/methanol as eluents. Both thin layer chromatography and high-performance liquid chromatography analyses confirmed the high efficiency of the isolation process with the purified orientin-6″-laurate, isoorientin-6″-laurate, vitexin-6″-laurate, and isovitexin-6″-laurate that were obtained. The addition of AOB and acylated AOB reduced acrylamide formation in fried potato crisps. Results showed that 0.05% AOB and 0.05% and 0.1% acylated AOB groups significantly (p < 0.05) reduced the content of acrylamide in potato crisps by 30.7%, 44.5%, and 46.9%, respectively. PMID:26098744

  6. Acylation of Antioxidant of Bamboo Leaves with Fatty Acids by Lipase and the Acylated Derivatives’ Efficiency in the Inhibition of Acrylamide Formation in Fried Potato Crisps

    PubMed Central

    Ma, Xiang; Wang, Erpei; Lu, Yuyun; Wang, Yong; Ou, Shiyi; Yan, Rian

    2015-01-01

    This study selectively acylated the primary hydroxyl groups on flavonoids in antioxidant of bamboo leaves (AOB) using lauric acid with Candida antarctica lipase B in tert-amyl-alcohol. The separation and isolation of acylated derivatives were performed using silica gel column chromatography with a mixture of dichloromethane/diethyl ether/methanol as eluents. Both thin layer chromatography and high-performance liquid chromatography analyses confirmed the high efficiency of the isolation process with the purified orientin-6″-laurate, isoorientin-6″-laurate, vitexin-6″-laurate, and isovitexin-6″-laurate that were obtained. The addition of AOB and acylated AOB reduced acrylamide formation in fried potato crisps. Results showed that 0.05% AOB and 0.05% and 0.1% acylated AOB groups significantly (p < 0.05) reduced the content of acrylamide in potato crisps by 30.7%, 44.5%, and 46.9%, respectively. PMID:26098744

  7. FlavonQ: An Automated Data Processing Tool for Profiling Flavone/flavonol Glycosides Using Ultra High-performance Liquid Chromatography Diode Array Detection and High-Resolution Accurate-Mass Mass Spectrometry (UHPLC HRAM-MS)

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Flavonoids are well-known for their health benefits and can be found in nearly every plant. There are more than 5,000 known flavonoids existing in foods. Profiling flavonoids in natural products poses great challenges due to the diversity of flavonoids, the lack of commercially available standards, ...

  8. Insights into the Inhibition of the p90 Ribosomal S6 Kinase (RSK) by the Flavonol Glycoside SL0101 from the 1.5 Å Crystal Structure of the N-Terminal Domain of RSK2 with Bound Inhibitor

    SciTech Connect

    Utepbergenov, Darkhan; Derewenda, Urszula; Olekhnovich, Natalya; Szukalska, Gabriela; Banerjee, Budhaditya; Hilinski, Michael K.; Lannigan, Deborah A.; Stukenberg, P. Todd; Derewenda, Zygmunt S.

    2012-09-11

    The p90 ribosomal S6 family of kinases (RSK) are potential drug targets, due to their involvement in cancer and other pathologies. There are currently only two known selective inhibitors of RSK, but the basis for selectivity is not known. One of these inhibitors is a naturally occurring kaempferol-a-l-diacetylrhamnoside, SL0101. Here, we report the crystal structure of the complex of the N-terminal kinase domain of the RSK2 isoform with SL0101 at 1.5 {angstrom} resolution. The refined atomic model reveals unprecedented structural reorganization of the protein moiety, as compared to the nucleotide-bound form. The entire N-lobe, the hinge region, and the aD-helix undergo dramatic conformational changes resulting in a rearrangement of the nucleotide binding site with concomitant formation of a highly hydrophobic pocket spatially suited to accommodate SL0101. These unexpected results will be invaluable in further optimization of the SL0101 scaffold as a promising lead for a novel class of kinase inhibitors.

  9. Ortho C-H Acylation of Aryl Iodides by Palladium/Norbornene Catalysis.

    PubMed

    Dong, Zhe; Wang, Jianchun; Ren, Zhi; Dong, Guangbin

    2015-10-19

    Reported herein is a palladium/norbornene-catalyzed ortho-arene acylation of aryl iodides by a Catellani-type C-H functionalization. This transformation is enabled by isopropyl carbonate anhydrides, which serve as both an acyl cation equivalent and a hydride source.

  10. Structural properties of pepsin-solubilized collagen acylated by lauroyl chloride along with succinic anhydride.

    PubMed

    Li, Conghu; Tian, Zhenhua; Liu, Wentao; Li, Guoying

    2015-10-01

    The structural properties of pepsin-solubilized calf skin collagen acylated by lauroyl chloride along with succinic anhydride were investigated in this paper. Compared with native collagen, acylated collagen retained the unique triple helix conformation, as determined by amino acid analysis, circular dichroism and X-ray diffraction. Meanwhile, the thermostability of acylated collagen using thermogravimetric measurements was enhanced as the residual weight increased by 5%. With the temperature increased from 25 to 115 °C, the secondary structure of native and acylated collagens using Fourier transform infrared spectroscopy measurements was destroyed since the intensity of the major amide bands decreased and the positions of the major amide bands shifted to lower wavenumber, respectively. Meanwhile, two-dimensional correlation spectroscopy revealed that the most sensitive bands for acylated and native collagens were amide I and II bands, respectively. Additionally, the corresponding order of the groups between native and acylated collagens was different and the correlation degree for acylated collagen was weaker than that of native collagen, suggesting that temperature played a small influence on the conformation of acylated collagen, which might be concluded that the hydrophobic interaction improved the thermostability of collagen.

  11. Nitrite-Oxidizing Bacterium Nitrobacter winogradskyi Produces N-Acyl-Homoserine Lactone Autoinducers

    PubMed Central

    Bottomley, Peter J.

    2015-01-01

    Nitrobacter winogradskyi is a chemolithotrophic bacterium that plays a role in the nitrogen cycle by oxidizing nitrite to nitrate. Here, we demonstrate a functional N-acyl-homoserine lactone (acyl-HSL) synthase in this bacterium. The N. winogradskyi genome contains genes encoding a putative acyl-HSL autoinducer synthase (nwi0626, nwiI) and a putative acyl-HSL autoinducer receptor (nwi0627, nwiR) with amino acid sequences 38 to 78% identical to those in Rhodopseudomonas palustris and other Rhizobiales. Expression of nwiI and nwiR correlated with acyl-HSL production during culture. N. winogradskyi produces two distinct acyl-HSLs, N-decanoyl-l-homoserine lactone (C10-HSL) and a monounsaturated acyl-HSL (C10:1-HSL), in a cell-density- and growth phase-dependent manner, during batch and chemostat culture. The acyl-HSLs were detected by bioassay and identified by ultraperformance liquid chromatography with information-dependent acquisition mass spectrometry (UPLC-IDA-MS). The C=C bond in C10:1-HSL was confirmed by conversion into bromohydrin and detection by UPLC-IDA-MS. PMID:26092466

  12. Synthesis of photoactivatable azido-acyl caged oxazine fluorophores for live-cell imaging.

    PubMed

    Anzalone, Andrew V; Chen, Zhixing; Cornish, Virginia W

    2016-07-19

    We report the design and synthesis of a photoactivatable azido-acyl oxazine fluorophore. Photoactivation is achieved cleanly and rapidly with UV light, producing a single fluorescent oxazine photoproduct. We demonstrate the utility of azido-acyl caged oxazines for protein specific labeling in living mammalian cells using the TMP-tag technology. PMID:27377037

  13. Nitrite-Oxidizing Bacterium Nitrobacter winogradskyi Produces N-Acyl-Homoserine Lactone Autoinducers.

    PubMed

    Mellbye, Brett L; Bottomley, Peter J; Sayavedra-Soto, Luis A

    2015-09-01

    Nitrobacter winogradskyi is a chemolithotrophic bacterium that plays a role in the nitrogen cycle by oxidizing nitrite to nitrate. Here, we demonstrate a functional N-acyl-homoserine lactone (acyl-HSL) synthase in this bacterium. The N. winogradskyi genome contains genes encoding a putative acyl-HSL autoinducer synthase (nwi0626, nwiI) and a putative acyl-HSL autoinducer receptor (nwi0627, nwiR) with amino acid sequences 38 to 78% identical to those in Rhodopseudomonas palustris and other Rhizobiales. Expression of nwiI and nwiR correlated with acyl-HSL production during culture. N. winogradskyi produces two distinct acyl-HSLs, N-decanoyl-l-homoserine lactone (C10-HSL) and a monounsaturated acyl-HSL (C10:1-HSL), in a cell-density- and growth phase-dependent manner, during batch and chemostat culture. The acyl-HSLs were detected by bioassay and identified by ultraperformance liquid chromatography with information-dependent acquisition mass spectrometry (UPLC-IDA-MS). The C=C bond in C10:1-HSL was confirmed by conversion into bromohydrin and detection by UPLC-IDA-MS.

  14. Turnover of the 4'-phosphopantetheine prosthetic group of acyl carrier protein.

    PubMed

    Jackowski, S; Rock, C O

    1984-02-10

    Acyl carrier protein is an essential cofactor in fatty acid biosynthesis, and in contrast to the stability of the protein moiety during growth, its 4'-phosphopantetheine prosthetic group is metabolically active. The biosynthetic incorporation of deuterium into nonexchangeable positions of acyl carrier protein was found to enhance the sensitivity of the protein to pH-induced hydrodynamic expansion. This constitutional isotope effect was exploited to separate deuterated from normal acyl carrier protein by conformationally sensitive gel electrophoresis, thus providing the analytical framework for separating pre-existing (deuterated) from newly synthesized acyl carrier protein in pulse-chase experiments. The rate of acyl carrier protein prosthetic group turnover was found to depend on the intracellular concentration of coenzyme A. At low coenzyme A levels, prosthetic group turnover was four times faster than the rate of new acyl carrier protein biosynthesis but at the higher coenzyme A concentrations characteristic of logarithmic growth, turnover was an order of magnitude slower, amounting to approximately 25% of the acyl carrier protein pool per generation. These observations suggest that the acyl carrier protein prosthetic group turnover cycle may be related to coenzyme A metabolism rather than to lipid biosynthesis.

  15. Quantitative analysis of the flavonoid glycosides and terpene trilactones in the extract of Ginkgo biloba and evaluation of their inhibitory activity towards fibril formation of β-amyloid peptide.

    PubMed

    Xie, Haiyan; Wang, Jing-Rong; Yau, Lee-Fong; Liu, Yong; Liu, Liang; Han, Quan-Bin; Zhao, Zhongzhen; Jiang, Zhi-Hong

    2014-04-10

    The standard extract of Ginkgo biloba leaves (EGb761) is used clinically in Europe for the symptomatic treatment of impaired cerebral function in primary degenerative dementia syndromes, and the results of numerous in vivo and in vitro studies have supported such clinical use. The abnormal production and aggregation of amyloid β peptide (Aβ) and the deposition of fibrils in the brain are regarded as key steps in the onset of Alzheimer's Disease (AD), and the inhibition of Aβ aggregation and destabilization of the preformed fibrils represent viable approaches for the prevention and treatment of AD. Flavonoid glycosides and terpene trilactones (TTLs) are the two main components of EGb761 which represent 24 and 6% of the overall content, respectively. In our research, seven abundant flavonoid glycosides 1-7 were isolated from the extract of Ginkgo biloba leaves and characterized by spectroscopic analysis. Furthermore, an ultra-high performance liquid chromatography method was established for the simultaneous quantification of these seven flavonoids. The inhibitory activities of these flavonoids, as well as four TTLs, i.e., ginkgolides A, B, and C and bilobalide (compounds 8-11), were evaluated towards Aβ42 fibril formation using a thioflavin T fluorescence assay. It was found that three flavonoids 1, 3 and 4 exhibited moderate inhibitory activities, whereas the other four flavonoids 2, 5, 6 and 7, as well as the four terpene trilactones, showed poor activity. This is the first report of the inhibition of Aβ fibril formation of two characteristic acylated flavonoid glycosides 6, 7 in Ginkgo leaves, on the basis of which the structure-activity relationship of these flavonoids 1-7 was discussed.

  16. Measurement of tissue acyl-CoAs using flow-injection tandem mass spectrometry: acyl-CoA profiles in short-chain fatty acid oxidation defects

    PubMed Central

    Palladino, Andrew A.; Chen, Jie; Kallish, Staci; Stanley, Charles A.; Bennett, Michael J.

    2013-01-01

    The primary accumulating metabolites in fatty acid oxidation defects are intramitochondrial acyl-CoAs. Typically, secondary metabolites such as acylcarnitines, acylglycines and dicarboxylic acids are measured to study these disorders. Methods have not been adapted for tissue acyl-CoA measurement in defects with primarily acyl-CoA accumulation. Our objective was to develop a method to measure fatty acyl-CoA species that are present in tissues of mice with fatty acid oxidation defects using flow-injection tandem mass spectrometry. Following the addition of internal standards of [13C2] acetyl-CoA, [13C8] octanoyl-CoA, and [C17] heptadecanoic CoA, acyl-CoA’s are extracted from tissue samples and are injected directly into the mass spectrometer. Data is acquired using a 506.9 neutral loss scan and multiple reaction-monitoring (MRM). This method can identify all long, medium and short-chain acyl-CoA species in wild type mouse liver including predicted 3-hydroxyacyl-CoA species. We validated the method using liver of the short-chain-acyl-CoA dehydrogenase (SCAD) knock-out mice. As expected, there is a significant increase in [C4] butyryl-CoA species in the SCAD −/− mouse liver compared to wild type. We then tested the assay in liver from the short-chain 3-hydroxyacyl-CoA dehydrogenase (SCHAD) deficient mice to determine the profile of acyl-CoA accumulation in this less predictable model. There was more modest accumulation of medium chain species including 3-hydroxyacyl-CoA’s consistent with the known chain-length specificity of the SCHAD enzyme. PMID:23117082

  17. Membrane Topology and Transient Acylation of Toxoplasma gondii Glycosylphosphatidylinositols

    PubMed Central

    Kimmel, Jürgen; Smith, Terry K.; Azzouz, Nahid; Gerold, Peter; Seeber, Frank; Lingelbach, Klaus; Dubremetz, Jean-François; Schwarz, Ralph T.

    2006-01-01

    Using hypotonically permeabilized Toxoplasma gondii tachyzoites, we investigated the topology of the free glycosylphosphatidylinositols (GPIs) within the endoplasmic reticulum (ER) membrane. The morphology and permeability of parasites were checked by electron microscopy and release of a cytosolic protein. The membrane integrity of organelles (ER and rhoptries) was checked by protease protection assays. In initial experiments, GPI biosynthetic intermediates were labeled with UDP-[6-3H]GlcNAc in permeabilized parasites, and the transmembrane distribution of the radiolabeled lipids was probed with phosphatidylinositol-specific phospholipase C (PI-PLC). A new early intermediate with an acyl modification on the inositol was identified, indicating that inositol acylation also occurs in T. gondii. A significant portion of the early GPI intermediates (GlcN-PI and GlcNAc-PI) could be hydrolyzed following PI-PLC treatment, indicating that these glycolipids are predominantly present in the cytoplasmic leaflet of the ER. Permeabilized T. gondii parasites labeled with either GDP-[2-3H]mannose or UDP-[6-3H]glucose showed that the more mannosylated and side chain (Glc-GalNAc)-modified GPI intermediates are also preferentially localized in the cytoplasmic leaflet of the ER. PMID:16896225

  18. Fatty acid hydrolysis of acyl marinobactin siderophores by Marinobacter acylases.

    PubMed

    Kem, Michelle P; Naka, Hiroaki; Iinishi, Akira; Haygood, Margo G; Butler, Alison

    2015-01-27

    The marine bacteria Marinobacter sp. DS40M6 and Marinobacter nanhaiticus D15-8W produce a suite of acyl peptidic marinobactin siderophores to acquire iron under iron-limiting conditions. During late-log phase growth, the marinobactins are hydrolyzed to form the marinobactin headgroup with release of the corresponding fatty acid tail. The bntA gene, a homologue of the Pseudomonas aeruginosa pyoverdine acylase gene, pvdQ, was identified from Marinobacter sp. DS40M6. A bntA knockout mutant of Marinobacter sp. DS40M6 produced the suite of acyl marinobactins A-E, without the usual formation of the marinobactin headgroup. Another marinobactin-producing species, M. nanhaiticus D15-8W, is predicted to have two pvdQ homologues, mhtA and mhtB. MhtA and MhtB have 67% identical amino acid sequences. MhtA catalyzes hydrolysis of the apo-marinobactin siderophores as well as the quorum sensing signaling molecule, dodecanoyl-homoserine lactone. In contrast to hydrolysis of the suite of apo-marinobactins by MhtA, hydrolysis of the iron(III)-bound marinobactins was not observed. PMID:25588131

  19. Site‐Selective Acylations with Tailor‐Made Catalysts

    PubMed Central

    Huber, Florian

    2016-01-01

    Abstract The acylation of alcohols catalyzed by N,N‐dimethylamino pyridine (DMAP) is, despite its widespread use, sometimes confronted with substrate‐specific problems: For example, target compounds with multiple hydroxy groups may show insufficient selectivity for one hydroxyl, and the resulting product mixtures are hardly separable. Here we describe a concept that aims at tailor‐made catalysts for the site‐specific acylation. To this end, we introduce a catalyst library where each entry is constructed by connecting a variable and readily tuned peptide scaffold with a catalytically active unit based on DMAP. For selected examples, we demonstrate how library screening leads to the identification of optimized catalysts, and the substrates of interest can be converted with a markedly enhanced site‐selectivity compared with only DMAP. Furthermore, substrate‐optimized catalysts of this type can be used to selectively convert “their” substrate in the presence of structurally similar compounds, an important requisite for reactions with mixtures of substances. PMID:26970553

  20. Acylation of salmon calcitonin modulates in vitro intestinal peptide flux through membrane permeability enhancement.

    PubMed

    Trier, Sofie; Linderoth, Lars; Bjerregaard, Simon; Strauss, Holger M; Rahbek, Ulrik L; Andresen, Thomas L

    2015-10-01

    Acylation of peptide drugs with fatty acid chains has proven beneficial for prolonging systemic circulation, as well as increasing enzymatic stability and interactions with lipid cell membranes. Thus, acylation offers several potential benefits for oral delivery of therapeutic peptides, and we hypothesize that tailoring the acylation may be used to optimize intestinal translocation. This work aims to characterize acylated analogues of the therapeutic peptide salmon calcitonin (sCT), which lowers blood calcium, by systematically increasing acyl chain length at two positions, in order to elucidate its influence on intestinal cell translocation and membrane interaction. We find that acylation drastically increases in vitro intestinal peptide flux and confers a transient permeability enhancing effect on the cell layer. The analogues permeabilize model lipid membranes, indicating that the effect is due to a solubilization of the cell membrane, similar to transcellular oral permeation enhancers. The effect is dependent on pH, with larger effect at lower pH, and is impacted by acylation chain length and position. Compared to the unacylated peptide backbone, N-terminal acylation with a short chain provides 6- or 9-fold increase in peptide translocation at pH 7.4 and 5.5, respectively. Prolonging the chain length appears to hamper translocation, possibly due to self-association or aggregation, although the long chain acylated analogues remain superior to the unacylated peptide. For K(18)-acylation a short chain provides a moderate improvement, whereas medium and long chain analogues are highly efficient, with a 12-fold increase in permeability compared to the unacylated peptide backbone, on par with currently employed oral permeation enhancers. For K(18)-acylation the medium chain acylation appears to be optimal, as elongating the chain causes greater binding to the cell membrane but similar permeability, and we speculate that increasing the chain length further may