Ethylene promotes mycelial growth and ganoderic acid biosynthesis in Ganoderma lucidum.
Zhang, Guang; Ren, Ang; Wu, Fengli; Yu, Hanshou; Shi, Liang; Zhao, Mingwen
2017-02-01
To investigate the effects of ethylene, in the form of ethephon (2-chloroethylphosphonic acid), on mycelial growth and ganoderic acid (GA) accumulation in the higher basidiomycete Ganoderma lucidum. Treatment with both 10 and 15 mM ethephon enhanced the growth of G. lucidum on solid CYM plates and in CYM liquid medium. After optimization using response surface methodology, GA reached 33 mg/g dry cell weight (DW), an increase of 90 %, compared with the control. Lanosterol and squalene contents were 31 and 2.4 μg/g DW, being increased by 1.2- and 0.6-fold, respectively, in response to ethephon. Additionally, the transcriptional levels of hydroxymethylglutaryl-CoA reductase, squalene synthase and oxidosqualene cyclase were up-regulated by 2.6-, 4.3- and 3.8-fold, respectively, compared with the control group. This approach provides an efficient strategy for improving GA accumulation in G. lucidum, with potential future applications.
Transport and Metabolism of 3H-Gibberellin A1 in Dioecious Cucumber Seedlings 1
Rudich, Jehoshua; Sell, Harold M.; Baker, Larry R.
1976-01-01
The transport of 3H-GA1 through hypocotyl segments of cucumber (Cucumis sativus L.) was found to be nonpolar. The transport of 3H-GA1 was increased by pretreatment with relatively high concentrations of either IAA or Ethephon (2-chloroethylphosphonic acid). Hypocotyl segments from plants of a gynoecious genotype transported more 3H-GA1 than those of an androecious. The metabolism of 3H-GA1 in hypocotyl segments was neither related to the sex genotype of the cucumber plant nor influenced by pretreatment with Ethephon. The primary metabolite of GA1 was suggested to be GA8. Two other suspected metabolites were not identified. Differences in the endogenous GA of gynoecious and androecious plants could not be accounted for by transport differences. PMID:16659561
Skrzypek, Edyta; Miyamoto, Kensuke; Saniewski, Marian; Ueda, Junichi
2005-05-01
The purpose of this study was to know the mechanism of jasmonates to induce gummosis in tulip (Tulipa gesneriana L. cv. Apeldoorn) shoots, especially on the focus of sugar metabolism. Gummosis in the first internode of tulip plants was induced by the application of methyl jasmonate (JA-Me, 1% w/w in lanolin) and jasmonic acid (JA, 1% w/w in lanolin) 5 days after application and strongly stimulated by the simultaneous application of ethylene-releasing compound, ethephon (2-chloroethylphosphonic acid, 1% w/w in lanolin), although ethephon alone had little effect. JA-Me stimulated ethylene production of the first internodes of tulips, ethylene production increasing up to more than 5 times at day 1 and day 3 after the application. On the other hand, application of ethephon did not increase endogenous levels of jasmonates in tulip stems. Analysis of composition of tulip gums revealed that they were consisted of glucuronoarabinoxylan with an average molecular weight of ca. 700 kDa. JA-Me strongly decreased the total amount of soluble sugars in tulip stems even in 1 day after application, being ca. 50% of initial values 5 days after application, but ethephon did not. However, both JA-Me and ethephon had almost no effect on the neutral sugar compositions of soluble sugars mainly consisting of glucose, mannose and xylose in ratio of 20:2:1 and traces of arabinose. Both JA-Me and ethephon applied exogenously stimulated senescence of tulip shoots shown by the loss of chlorophyll. These results strongly suggest that the essential factor of gummosis in tulips is jasmonates affecting the sugar metabolism in tulip shoots. The mode of action of jasmonates to induce gummosis of tulip shoots is discussed in relation to ethylene production, sugar metabolism and senescence.
Kinetic Studies of the Thermal Decomposition of 2-Chloroethylphosphonic Acid in Aqueous Solution
Biddle, Eric; Kerfoot, Douglas G. S.; Kho, Yioe Hwa; Russell, Kenneth E.
1976-01-01
The decomposition of 2-chloroethylphosphonic acid in aqueous solution has been studied at pH values from 6 to 9 and at temperatures in the 30 to 55 C range. The rate of decomposition is estimated from the rate of formation of ethylene. The rate is proportional to the concentration of the phosphonate dianion and is independent of the hydroxyl ion concentration. The rate constant at 40 C is 1.9 × 10−4 sec−1 and the activation energy is 29.8 kcal mol−1. The rate of reaction is not affected significantly by the presence of potassium iodide or urea (substances which increase the rate of leaf abscission in trees sprayed by 2-chloroethylphosphonic acid). The rate decreases slightly in the presence of low concentrations of magnesium and calcium ions. PMID:16659748
Martin, Maria Teresa; Pedranzani, Hilda; García-Molinero, Patricia; Pando, Valentin; Sierra-de-Grado, Rosario
2009-12-01
Two independent parameters, epicotyl height (cm) and number of induced buds were studied on Pinus pinaster explants to analyse the effects of three phytohormones (6-benzylaminopurine, jasmonic acid, ethylene) which were combined or not in 11 different treatments. Epicotyle length diminished significantly in relation to the control medium (medium without exogen phytohormones) in presence of jasmonic acid, 6-benzylaminopurine or Ethephon (which is converted to ethylene in plants) in any of treatments. Concentrations of 100 microM of jasmonic acid and Ethephon had a greater inhibitory effect than the treatments with 10 microM. In addition to that, jasmonic acid was a stronger inhibitor than Ethephon in any of the tried combinations. There were no significant differences between the control treatment and the treatments with only 10 microM of jasmonic acid or Ethephon. However, 10 microM 6-benzylaminopurine induced bud formation. The different combinations of 6-benzylaminopurine with jasmonic acid and Ethephon showed that concentrations of 10 to 100 microM did not affect the number of induced buds. Jasmonic acid had an inhibitory effect which Ethephon only showed when combined with 100 microM of jasmonic acid and 10 microM of 6-benzylaminopurine. Three response groups were defined by cluster analysis: group 1 produced the greatest mean number of buds (4 to 5) and a mean epicotyl growth of 1 to 1.5 cm; group 2 produced 2 to 4 buds and a mean growth of 0.5 to 1.2 cm; group 3 produced only one bud and a mean epicotyl length of 1.2 to 2 cm.
Effect of Ethephon as an Ethylene-Releasing Compound on the Metabolic Profile of Chlorella vulgaris.
Kim, So-Hyun; Lim, Sa Rang; Hong, Seong-Joo; Cho, Byung-Kwan; Lee, Hookeun; Lee, Choul-Gyun; Choi, Hyung-Kyoon
2016-06-15
In this study, Chlorella vulgaris (C. vulgaris) was treated with ethephon at low (50 μM) and high (200 μM) concentrations in medium and harvested at 0, 7, and 14 days, respectively. The presence of ethephon led to significant metabolic changes in C. vulgaris, with significantly higher levels of α-tocopherol, γ-aminobutyric acid (GABA), asparagine, and proline, but lower levels of glycine, citrate, and galactose relative to control. Ethephon induced increases in saturated fatty acids but decreases in unsaturated fatty acids. The levels of highly saturated sulfoquinovosyldiacylglycerol species and palmitic acid bound phospholipids were increased on day 7 of ethephon treatment. Among the metabolites, the productivities of α-tocopherol (0.70 μg/L/day) and GABA (1.90 μg/L/day) were highest for 50 and 200 μM ethephon on day 7, respectively. We propose that ethephon treatment involves various metabolic processes in C. vulgaris and can be an efficient way to enrich the contents of α-tocopherol and GABA.
Khan, NA
2004-01-01
Background The stimulatory effect of CO2 on ethylene evolution in plants is known, but the extent to which ethylene controls photosynthesis is not clear. Studies on the effects of ethylene on CO2 metabolism have shown conflicting results. Increase or inhibition of photosynthesis by ethylene has been reported. To understand the physiological processes responsible for ethylene-mediated changes in photosynthesis, stomatal and mesophyll effects on photosynthesis and ethylene biosynthesis in response to ethephon treatment in mustard (Brassica juncea) cultivars differing in photosynthetic capacity were studied. Results The effects of ethephon on photosynthetic rate (PN), stomatal conductance (gS), carbonic anhydrase (CA) activity, 1-aminocyclopropane carboxylic acid synthase (ACS) activity and ethylene evolution were similar in both the cultivars. Increasing ethephon concentration up to 1.5 mM increased PN, gS and CA maximally, whereas 3.0 mM ethephon proved inhibitory. ACS activity and ethylene evolution increased with increasing concentrations of ethephon. The corresponding changes in gs and CA activity suggest that the changes in photosynthesis in response to ethephon were triggered by altered stomatal and mesophyll processes. Stomatal conductance changed in parallel with changes in mesophyll photosynthetic properties. In both the cultivars ACS activity and ethylene increased up to 3.0 mM ethephon, but 1.5 mM ethephon caused maximum effects on photosynthetic parameters. Conclusion These results suggest that ethephon affects foliar gas exchange responses. The changes in photosynthesis in response to ethephon were due to stomatal and mesophyll effects. The changes in gS were a response maintaining stable intercellular CO2 concentration (Ci) under the given treatment in both the cultivars. Also, the high photosynthetic capacity cultivar, Varuna responded less to ethephon than the low photosynthetic capacity cultivar, RH30. The photosynthetic capacity of RH30 increased with the increase in ethylene evolution due to 1.5 mM ethephon application. PMID:15625009
Chen, Bingxian; Ma, Jun; Xu, Zhenjiang; Wang, Xiaofeng
2016-10-01
The purpose of this study was to investigate the role of cellulase in endosperm cap weakening and radicle elongation during lettuce (Lactuca sativa L.) seed germination. The application of abscisic acid (ABA) or ethephon inhibits or promotes germination, respectively, by affecting endosperm cap weakening and radicle elongation. Cellulase activities, and related protein and transcript abundances of two lettuce cellulase genes, LsCEL1 and LsCEL2, increase in the endosperm cap and radicle prior to radicle protrusion following imbibition in water. ABA or ethephon reduce or elevate, respectively, cellulase activity, and related protein and transcript abundances in the endosperm cap. Taken together, these observations suggest that cellulase plays a role in endosperm cap weakening and radicle elongation during lettuce seed germination, and that the regulation of cellulase in the endosperm cap by ABA and ethephon play a role in endosperm cap weakening. However, the influence of ABA and ethephon on radicle elongation may not be through their effects on cellulase. © 2016 Institute of Botany, Chinese Academy of Sciences.
Royer, A; Laporte, F; Bouchonnet, S; Communal, P-Y
2006-03-03
An analytical method has been developed for the determination of residues of ethephon (2-chloroethyl phosphonic acid) in drinking and surface water. The procedure is based on de-ionisation with an anion/cation-exchange resin, solid phase extraction by means of anion-exchange polystyrene-divinylbenzene extraction disks, elution with a mixture of methanol and 10 M hydrochloric acid (98/2, v/v), redisolution into acetonitrile after evaporation and silylation with N-(tert-butyldimethylsilyl)-N-methyltrifluoroacetamide (MTBSTFA). Quantification is performed by gas chromatography with ion-trap cubic mass spectrometric detection in the electron impact mode (GC-EI-MS3). Method validation was conducted using samples of mineral, tap, and river water that were fortified with ethephon at concentration levels ranging from 0.1 to 1.0 microg/L. The mean recovery from all the fortified samples (n = 36) amounted to 88% with a relative standard deviation of 17%. The method, therefore, was shown to allow accurate determination of ethephon residues in drinking and surface water with a limit of quantification of 0.1 microg/L.
Goldental-Cohen, S; Burstein, C; Biton, I; Ben Sasson, S; Sadeh, A; Many, Y; Doron-Faigenboim, A; Zemach, H; Mugira, Y; Schneider, D; Birger, R; Meir, S; Philosoph-Hadas, S; Irihomovitch, V; Lavee, S; Avidan, B; Ben-Ari, G
2017-05-16
Table olives (Olea europaea L.), despite their widespread production, are still harvested manually. The low efficiency of manual harvesting and the rising costs of labor have reduced the profitability of this crop. A selective abscission treatment, inducing abscission of fruits but not leaves, is crucial for the adoption of mechanical harvesting of table olives. In the present work we studied the anatomical and molecular differences between the three abscission zones (AZs) of olive fruits and leaves. The fruit abscission zone 3 (FAZ3), located between the fruit and the pedicel, was found to be the active AZ in mature fruits and is sensitive to ethephon, whereas FAZ2, between the pedicel and the rachis, is the flower active AZ as well as functioning as the most ethephon induced fruit AZ. We found anatomical differences between the leaf AZ (LAZ) and the two FAZs. Unlike the FAZs, the LAZ is characterized by small cells with less pectin compared to neighboring cells. In an attempt to differentiate between the fruit and leaf AZs, we examined the effect of treating olive-bearing trees with ethephon, an ethylene-releasing compound, with or without antioxidants, on the detachment force (DF) of fruits and leaves 5 days after the treatment. Ethephon treatment enhanced pectinase activity and reduced DF in all the three olive AZs. A transcriptomic analysis of the three olive AZs after ethephon treatment revealed induction of several genes encoding for hormones (ethylene, auxin and ABA), as well as for several cell wall degrading enzymes. However, up-regulation of cellulase genes was found only in the LAZ. Many genes involved in oxidative stress were induced by the ethephon treatment in the LAZ alone. In addition, we found that reactive oxygen species (ROS) mediated abscission in response to ethephon only in leaves. Thus, adding antioxidants such as ascorbic acid or butyric acid to the ethephon inhibited leaf abscission but enhanced fruit abscission. Our findings suggest that treating olive-bearing trees with a combination of ethephon and antioxidants reduces the detachment force (DF) of fruit without weakening that of the leaves. Hence, this selective abscission treatment may be used in turn to promote mechanized harvest of olives.
Ferrara, Giuseppe; Mazzeo, Andrea; Matarrese, Angela M. S.; Pacucci, Carmela; Trani, Antonio; Fidelibus, Matthew W.; Gambacorta, Giuseppe
2016-01-01
Some plant growth regulators, including ethephon, can stimulate abscission of mature grape berries. The stimulation of grape berry abscission reduces fruit detachment force (FDF) and promotes the development of a dry stem scar, both of which could facilitate the production of high quality stemless fresh-cut table grapes. The objective of this research was to determine how two potential abscission treatments, 1445 and 2890 mg/L ethephon, affected FDF, pre-harvest abscission, fruit quality, and ethephon residue of Thompson Seedless and Crimson Seedless grapes. Both ethephon treatments strongly induced abscission of Thompson Seedless berries causing >90% pre-harvest abscission. Lower ethephon rates, a shorter post-harvest interval, or berry retention systems such as nets, would be needed to prevent excessive pre-harvest losses. The treatments also slightly affected Thompson Seedless berry skin color, with treated fruit being darker, less uniform in color, and with a more yellow hue than non-treated fruit. Ethephon residues on Thompson Seedless grapes treated with the lower concentration of ethephon were below legal limits at harvest. Ethephon treatments also promoted abscission of Crimson Seedless berries, but pre-harvest abscission was much lower (≅49%) in Crimson Seedless compared to Thompson Seedless. Treated fruits were slightly darker than non-treated fruits, but ethephon did not affect SSC, acidity, or firmness of Crimson Seedless, and ethephon residues were below legal limits. PMID:27303407
Chen, Hsien-Jung; Huang, Yu-Hsuan; Huang, Guan-Jhong; Huang, Shyh-Shyun; Chow, Te-Jin; Lin, Yaw-Huei
2015-05-15
Plant aspartic proteases are generally divided into three categories: typical, nucellin-like, and atypical aspartic proteases based on their gene and protein structures. In this report, a full-length cDNA SPAP1 was cloned from sweet potato leaves, which contained 1515 nucleotides (504 amino acids) and exhibited high amino acid sequence identity (ca. 51-72%) with plant typical aspartic proteases, including tomato LeAspP, potato StAsp, and wheat WAP2. SPAP1 also contained conserved DTG and DSG amino acid residues within its catalytic domain and plant specific insert (PSI) at the C-terminus. The cDNA corresponding to the mature protein (starting from the 66th to 311th amino acid residues) without PSI domain was constructed with pET30a expression vector for fusion protein and antibody production. RT-PCR and protein blot hybridization showed that SPAP1 expression level was the highest in L3 mature leaves, then gradually declined until L5 completely yellow leaves. Ethephon, an ethylene-releasing compound, also enhanced SPAP1 expression at the time much earlier than the onset of leaf senescence. Exogenous application of SPAP1 fusion protein promoted ethephon-induced leaf senescence, which could be abolished by pre-treatment of SPAP1 fusion protein with (a) 95 °C for 5 min, (b) aspartic protease inhibitor pepstatin A, and (c) anti-SPAP1 antibody, respectively. Exogenous SPAP1 fusion protein, whereas, did not significantly affect leaf senescence under dark. These data conclude that sweet potato SPAP1 is a functional typical aspartic protease and participates in ethephon-mediated leaf senescence. The SPAP1-promoted leaf senescence and its activity are likely not associated with the PSI domain. Interaction of ethephon-inducible components for effective SPAP1 promotion on leaf senescence is also suggested. Copyright © 2015 Elsevier GmbH. All rights reserved.
Gravitropism in Higher Plant Shoots 1
Wheeler, Raymond M.; White, Rosemary G.; Salisbury, Frank B.
1986-01-01
Ethylene at 1.0 and 10.0 cubic centimeters per cubic meter decreased the rate of gravitropic bending in stems of cocklebur (Xanthium strumarium L.) and tomato (Lycopersicon esculentum Mill), but 0.1 cubic centimeter per cubic meter ethylene had little effect. Treating cocklebur plants with 1.0 millimolar aminoethoxyvinylglycine (AVG) (ethylene synthesis inhibitor) delayed stem bending compared with controls, but adding 0.1 cubic centimeter per cubic meter ethylene in the surrounding atmosphere (or applying 0.1% ethephon solution) partially restored the rate of bending of AVG-treated plants. Ethylene increases in bending stems, and AVG inhibits this. Virtually all newly synthesized ethylene appeared in bottom halves of horizontal stems, where ethylene concentrations were as much as 100 times those in upright stems or in top halves of horizontal stems. This was especially true when horizontal stems were physically restrained from bending. Ethylene might promote cell elongation in bottom tissues of a horizontal stem or indicate other factors there (e.g. a large amount of `functioning' auxin). Or top and bottom tissues may become differentially sensitive to ethylene. Auxin applied to one side of a vertical stem caused extreme bending away from that side; gibberellic acid, kinetin, and abscisic acid were without effect. Acidic ethephon solutions applied to one side of young seedlings of cocklebur, tomato, sunflower (Helianthus annuus L.), and soybean (Glycine max [L.] Merr.) caused bending away from that side, but neutral ethephon solutions did not cause bending. Buffered or unbuffered acid (HCl) caused similar bending. Neutral ethephon solutions produced typical ethylene symptoms (i.e. epinasty, inhibition of stem elongation). HCl or acidic ethephon applied to the top of horizontal stems caused downward bending, but these substances applied to the bottom of such stems inhibited growth and upward bending—an unexpected result. PMID:11539089
Gravitropism in Leafy Dicot Stems
NASA Technical Reports Server (NTRS)
Salisbury, F. B.
1985-01-01
A polarizing research microscope with rotating stage and associated camera equipment were ordered, and techniques of fixation and preparation of specimens were perfected for studying possible changes in orientation of cellulose microfibrils in cell walls of gravistimulated dicot stems. Acid ethephon solutions or acid without ethephon caused elongation of stem tissues where they were applied; stems bent away from the side of application. Acid solutions applied to the bottom of horizontal stems greatly delayed bending. Research in tissue sensitivity changes during gravitropic bending of soybean hypocotyls while immersed in auxin and in castor bean stems is also reported.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Vera, P.; Conejero, V.
The effect of ethephon (2-chloroetylphosphonic acid) on the degradation of proteins and on the induction of Lycopersicon esculentum pathogenesis-related (PR) proteins was studied in tomato leaf discs. The rate of ribulose, -1,5-bisphosphate carboxylase/oxygenase (Rubisco) degradation was maximal in discs after 48 hours of incubation with 1 millimolar ethephon, leading to complete disappearance of Rubisco after 96 hours. This effect was correlated with an increase in PR protein synthesis and the induction of the previously reported alkaline proteolytic enzyme PR-P69. In vivo pulse-chase experiments demonstrated that ethephon not only affected Rubisco content but that of many other {sup 35}S-labeled proteins asmore » well, indicating that ethylene activates a general and nonspecific mechanism of protein degradation. This effect was partially inhibited in vivo by the action of pCMB, a selective inhibitor of cysteine-proteinases such as P69. These data reinforce the hypothesis that P69 and perhaps other PR proteins are involved in the mechanism of accelerated protein degradation activated by ethylene.« less
Deng, Lili; Yuan, Ziyi; Xie, Jiao; Yao, Shixiang; Zeng, Kaifang
2017-08-02
Although citrus fruits are not climacteric, exogenous ethylene is widely used in the degreening treatment of citrus fruits. Irradiation with blue light-emitting diode (LED) light (450 nm) for 10 h can promote the formation of good coloration of ethephon-degreened fruit. This study evaluated the effect of blue LED light irradiation on the pigments contents of ethephon-degreened fruit and evaluated whether the blue LED light irradiation could influence the sensitivity of mandarin fruit to ethylene. The results indicated that blue light can accelerate the color change of ethephon-degreened fruit, accompanied by changes in plastid ultrastructure and chlorophyll and carotenoid contents. Ethephon-induced expressions of CitACS1, CitACO, CitETR1, CitEIN2, CitEIL1, and CitERF2 were enhanced by blue LED light irradiation, which increased the sensitivity to ethylene in ethephon-degreened fruits. These results indicate that blue LED light-induced changes in sensitivity to ethylene in mandarin fruit may be responsible for the improved coloration of ethephon-degreened mandarin fruits.
Ethylene-induced transcriptional and hormonal responses at the onset of sugarcane ripening
Cunha, Camila P.; Roberto, Guilherme G.; Vicentini, Renato; Lembke, Carolina G.; Souza, Glaucia M.; Ribeiro, Rafael V.; Machado, Eduardo C.; Lagôa, Ana M. M. A.; Menossi, Marcelo
2017-01-01
The effects of ethephon as a sugarcane ripener are attributed to ethylene. However, the role of this phytohormone at the molecular level is unknown. We performed a transcriptome analysis combined with the evaluation of sucrose metabolism and hormone profiling of sugarcane plants sprayed with ethephon or aminoethoxyvinylglycine (AVG), an ethylene inhibitor, at the onset of ripening. The differential response between ethephon and AVG on sucrose level and sucrose synthase activity in internodes indicates ethylene as a potential regulator of sink strength. The correlation between hormone levels and transcriptional changes suggests ethylene as a trigger of multiple hormone signal cascades, with approximately 18% of differentially expressed genes involved in hormone biosynthesis, metabolism, signalling, and response. A defence response elicited in leaves favoured salicylic acid over the ethylene/jasmonic acid pathway, while the upper internode was prone to respond to ethylene with strong stimuli on ethylene biosynthesis and signalling genes. Besides, ethylene acted synergistically with abscisic acid, another ripening factor, and antagonistically with gibberellin and auxin. We identified potential ethylene target genes and characterized the hormonal status during ripening, providing insights into the action of ethylene at the site of sucrose accumulation. A molecular model of ethylene interplay with other hormones is proposed. PMID:28266527
Costa, Anne P; Vendrame, Wagner; Nietsche, Sílvia; Crane, Jonathan; Moore, Kimberly; Schaffer, Bruce
2016-05-31
Jatropha curcas L. has been identified for biofuel production but it presents limited commercial yields due to limited branching and a lack of yield uniformity. The objective of this study was to evaluate the effects of single application of ethephon or a combination of 6-benzyladenine (BA) with gibberellic acid isomers A4 and A7 (GA4+7) on branch induction, flowering and fruit production in jatropha plants with and without leaves. Plants with and without leaves showed differences for growth and reproductive variables. For all variables except inflorescence set, there were no significant statistical interactions between the presence of leaves and plant growth regulators concentration. The total number of flowers per inflorescence was reduced as ethephon concentration was increased. As BA + GA4 +7 concentration increased, seed dry weight increased. Thus, ethephon and BA + GA4 +7 applications appeared to affect flowering and seed production to a greater extent than branching. The inability to discern significant treatment effects for most variables might have been due to the large variability within plant populations studied and thus resulting in an insufficient sample size. Therefore, data collected from this study were used for statistical estimations of sample sizes to provide a reference for future studies.
Hypobaric Control of Ethylene-Induced Leaf Senescence in Intact Plants of Phaseolus vulgaris L. 1
Nilsen, Karl N.; Hodges, Clinton F.
1983-01-01
A controlled atmospheric-environment system (CAES) designed to sustain normal or hypobaric ambient growing conditions was developed, described, and evaluated for its effectiveness as a research tool capable of controlling ethylene-induced leaf senescence in intact plants of Phaseolus vulgaris L. Senescence was prematurely-induced in primary leaves by treatment with 30 parts per million ethephon. Ethephon-derived endogenous ethylene reached peak levels within 6 hours at 26°C. Total endogenous ethylene levels then temporarily stabilized at approximately 1.75 microliters per liter from 6 to 24 hours. Thereafter, a progressive rise in ethylene resulted from leaf tissue metabolism and release. Throughout the study, the endogenous ethylene content of ethephon-treated leaves was greater than that of nontreated leaves. Subjecting ethephon-treated leaves to atmospheres of 200 millibars, with O2 and CO2 compositions set to approximate normal atmospheric partial pressures, prevented chlorophyll loss. Alternately, subjecting ethephon-treated plants to 200 millibars of air only partially prevented chlorophyll loss. Hypobaric conditions (200 millibars), with O2 and CO2 at normal atmospheric availability, could be delayed until 48 hours after ethephon treatment and still prevent most leaf senescence. In conclusion, hypobaric conditions established and maintained within the CAES prevented ethylene-induced senescence (chlorosis) in intact plants, provided O2 and CO2 partial pressures were maintained at levels approximating normal ambient availability. An unexpected increase in endogenous ethylene was detected within nontreated control leaves 48 hours subsequent to relocation from winter greenhouse conditions (latitude, 42°00″ N) to the CAES operating at normal ambient pressure. The longer photoperiod and/or higher temperature utilized within the CAES are hypothesized to influence ethylene metabolism directly and growth-promotive processes (e.g. response thresholds) indirectly. PMID:16662806
Nie, Zhiyi; Kang, Guijuan; Duan, Cuifang; Li, Yu; Dai, Longjun; Zeng, Rizhong
2016-01-01
Ethylene is commonly used as a latex stimulant of Hevea brasiliensis by application of ethephon (chloro-2-ethylphosphonic acid); however, the molecular mechanism by which ethylene increases latex production is not clear. To better understand the effects of ethylene stimulation on the laticiferous cells of rubber trees, a latex expressed sequence tag (EST)-based complementary DNA microarray containing 2,973 unique genes (probes) was first developed and used to analyze the gene expression changes in the latex of the mature virgin rubber trees after ethephon treatment at three different time-points: 8, 24 and 48 h. Transcript levels of 163 genes were significantly altered with fold-change values ≥ 2 or ≤ –2 (q-value < 0.05) in ethephon-treated rubber trees compared with control trees. Of the 163 genes, 92 were up-regulated and 71 down-regulated. The microarray results were further confirmed using real-time quantitative reverse transcript-PCR for 20 selected genes. The 163 ethylene-responsive genes were involved in several biological processes including organic substance metabolism, cellular metabolism, primary metabolism, biosynthetic process, cellular response to stimulus and stress. The presented data suggest that the laticifer water circulation, production and scavenging of reactive oxygen species, sugar metabolism, and assembly and depolymerization of the latex actin cytoskeleton might play important roles in ethylene-induced increase of latex production. The results may provide useful insights into understanding the molecular mechanism underlying the effect of ethylene on latex metabolism of H. brasiliensis. PMID:26985821
Montoro, Pascal; Wu, Shuangyang; Favreau, Bénédicte; Herlinawati, Eva; Labrune, Cécile; Martin-Magniette, Marie-Laure; Pointet, Stéphanie; Rio, Maryannick; Leclercq, Julie; Ismawanto, Sigit; Kuswanhadi
2018-05-31
Tapping Panel Dryness (TPD) affects latex production in Hevea brasiliensis. This physiological syndrome involves the agglutination of rubber particles, which leads to partial or complete cessation of latex flow. Latex harvesting consists in tapping soft bark. Ethephon can be applied to stimulate latex flow and its regeneration in laticifers. Several studies have reported transcriptome changes in bark tissues. This study is the first report on deep RNA sequencing of latex to compare the effect of ethephon stimulation and TPD severity. Trees were carefully selected for paired-end sequencing using an Illumina HiSeq 2000. In all, 43 to 60 million reads were sequenced for each treatment in three biological replicates (slight TPD trees without ethephon stimulation, and slight and severe TPD trees with ethephon treatment). Differentially expressed genes were identified and annotated, giving 8,111 and 728 in response to ethephon in slight TPD trees and in ethephon-induced severe TPD trees, respectively. A biological network of responses to ethephon and TPD highlighted the major influence of metabolic processes and the response to stimulus, especially wounding and jasmonate depression in TPD-affected trees induced by ethephon stimulation.
Ethephon induced abscission in mango: physiological fruitlet responses
Hagemann, Michael H.; Winterhagen, Patrick; Hegele, Martin; Wünsche, Jens N.
2015-01-01
Fruitlet abscission of mango is typically very severe, causing considerable production losses worldwide. Consequently, a detailed physiological and molecular characterization of fruitlet abscission in mango is required to describe the onset and time-dependent course of this process. To identify the underlying key mechanisms of abscission, ethephon, an ethylene releasing substance, was applied at two concentrations (600 and 7200 ppm) during the midseason drop stage of mango. The abscission process is triggered by ethylene diffusing to the abscission zone where it binds to specific receptors and thereby activating several key physiological responses at the cellular level. The treatments reduced significantly the capacity of polar auxin transport through the pedicel at 1 day after treatment and thereafter when compared to untreated pedicels. The transcript levels of the ethylene receptor genes MiETR1 and MiERS1 were significantly upregulated in the pedicel and pericarp at 1, 2, and 3 days after the ethephon application with 7200 ppm, except for MiETR1 in the pedicel, when compared to untreated fruitlet. In contrast, ethephon applications with 600 ppm did not affect expression levels of MiETR1 in the pedicel and of MiERS1 in the pericarp; however, MiETR1 in the pericarp at day 2 and MiERS1 in the pedicel at days 2 and 3 were significantly upregulated over the controls. Moreover, two novel short versions of the MiERS1 were identified and detected more often in the pedicel of treated than untreated fruitlets at all sampling times. Sucrose concentration in the fruitlet pericarp was significantly reduced to the control at 2 days after both ethephon treatments. In conclusion, it is postulated that the ethephon-induced abscission process commences with a reduction of the polar auxin transport capacity in the pedicel, followed by an upregulation of ethylene receptors and finally a decrease of the sucrose concentration in the fruitlets. PMID:26442021
Mitamura, Toshiaki; Shite, Masato; Yamamura, Yoshimi; Kurosaki, Fumiya
2009-06-01
A cDNA clone, designated Sd-racrop (969 bp), was isolated from seedlings of Scoparia dulcis. This gene contains an open reading frame encoding the protein of 197 amino acid residues with high homology to Rac/Rop small guanosine 5'-triphosphate-binding proteins from various plant sources. In Southern hybridization analysis, the restriction digests prepared from genomic DNA of S. dulcis showed a main signal together with a few weakly hybridized bands. The transcriptional level of Sd-racrop showed a transient decrease by exposure of the leaf tissues of S. dulcis to the ethylene-generating reagent 2-chloroethylphosphonic acid. However, an appreciable increase in gene expression was reproducibly observed upon treatment of the plant with methyl jasmonate. These results suggest that the Sd-racrop product plays roles in ethylene- and methyl jasmonate-induced responses of S. dulcis accompanying the change in the transcriptional level, however, the cellular events mediated by this protein toward these external stimuli would be regulated by various mechanisms.
Novel insights of ethylene role in strawberry cell wall metabolism.
Villarreal, Natalia M; Marina, María; Nardi, Cristina F; Civello, Pedro M; Martínez, Gustavo A
2016-11-01
Due to its organoleptic and nutraceutical qualities, strawberry fruit (Fragaria x ananassa, Duch) is a worldwide important commodity. The role of ethylene in the regulation of strawberry cell wall metabolism was studied in fruit from Toyonoka cultivar harvested at white stage, when most changes associated with fruit ripening have begun. Fruit were treated with ethephon, an ethylene-releasing reagent, or with 1-methylcyclopropene (1-MCP), a competitive inhibitor of ethylene action, maintaining a set of non-treated fruit as controls for each condition. Ethephon treated-fruit showed higher contents of hemicelluloses, cellulose and neutral sugars regarding controls, while 1-MCP-treated fruit showed a lower amount of those fractions. On the other hand, ethephon-treated fruit presented a lower quantity of galacturonic acid from ionically and covalently bound pectins regarding controls, while 1-MCP-treated fruit showed higher contents of those components. We also explored the ethylene effect over the mRNA accumulation of genes related to pectins and hemicelluloses metabolism, and a relationship between gene expression patterns and cell wall polysaccharides contents was shown. Moreover, we detected that strawberry necrotrophic pathogens growth more easily on plates containing cell walls from ethephon-treated fruit regarding controls, while a lower growth rate was observed when cell walls from 1-MCP treated fruit were used as the only carbon source, suggesting an effect of ethylene on cell wall structure. Around 60% of strawberry cell wall is made up of pectins, which in turns is 70% made by homogalacturonans. Our findings support the idea of a central role for pectins on strawberry fruit softening and a participation of ethylene in the regulation of this process. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.
Evaluation of tannins interactions in grape (Vitis vinifera L.) skins.
Rustioni, Laura; Fiori, Simone; Failla, Osvaldo
2014-09-15
Tannins have a central role in grapevine berries both for their physiological and enological implications. In the skin tissue they can be in vacuolar solution, or associated to the cell walls through weak or strong physicochemical interactions. The present work aims to separate vacuolar, non-covalently and covalently bonded tannins fractions. A specific extraction procedure was developed. A first extraction in ethanol at low temperature allowed the quantification of vacuolar tannins. An urea treatment followed by an ethanol extraction at room temperature was able to separate non-covalently bonded compounds. Finally an acid catalysis was used to break down proanthocyanidin covalent bonds. The method was validated on ripe grape samples of three cultivars, on berries developed in two sun exposure conditions. The Ethephon treatment effect was also evaluated. Beside the method development, a preliminary evaluation of the cultivar, exposition and Ethephon treatment effects are discussed. Copyright © 2014 Elsevier Ltd. All rights reserved.
BnNHL18A shows a localization change by stress-inducing chemical treatments
DOE Office of Scientific and Technical Information (OSTI.GOV)
Lee, Suk-Bae; Ham, Byung-Kook; Park, Jeong Mee
2006-01-06
The two genes, named BnNHL18A and BnNHL18B, showing sequence homology with Arabidopsis NDR1/HIN1-like (NHL) genes, were isolated from cDNA library prepared with oilseed rape (Brassica napus) seedlings treated with NaCl. The transcript level of BnNHL18A was increased by sodium chloride, ethephon, hydrogen peroxide, methyl jasmonate, or salicylic acid treatment. The coding regions of BnNHL18A and BnNHL18B contain a sarcolipin (SLN)-like sequence. Analysis of the localization of smGFP fusion proteins showed that BnNHL18A is mainly localized to endoplasmic reticulum (ER). This result suggests that the SLN-like sequence plays a role in retaining proteins in ER membrane in plants. In response tomore » NaCl, hydrogen peroxide, ethephon, and salicylic acid treatments, the protein localization of BnNHL18A was changed. Our findings suggest a common function of BnNHL18A in biotic and abiotic stresses, and demonstrate the presence of the shared mechanism of protein translocalization between the responses to plant pathogen and to osmotic stress.« less
Li, Caiqin; Wang, Yan; Ying, Peiyuan; Ma, Wuqiang; Li, Jianguo
2015-01-01
The high level of physiological fruitlet abscission in litchi (Litchi chinensis Sonn.) causes severe yield loss. Cell separation occurs at the fruit abscission zone (FAZ) and can be triggered by ethylene. However, a deep knowledge of the molecular events occurring in the FAZ is still unknown. Here, genome-wide digital transcript abundance (DTA) analysis of putative fruit abscission related genes regulated by ethephon in litchi were studied. More than 81 million high quality reads from seven ethephon treated and untreated control libraries were obtained by high-throughput sequencing. Through DTA profile analysis in combination with Gene Ontology and KEGG pathway enrichment analyses, a total of 2730 statistically significant candidate genes were involved in the ethephon-promoted litchi fruitlet abscission. Of these, there were 1867 early-responsive genes whose expressions were up- or down-regulated from 0 to 1 d after treatment. The most affected genes included those related to ethylene biosynthesis and signaling, auxin transport and signaling, transcription factors (TFs), protein ubiquitination, ROS response, calcium signal transduction, and cell wall modification. These genes could be clustered into four groups and 13 subgroups according to their similar expression patterns. qRT-PCR displayed the expression pattern of 41 selected candidate genes, which proved the accuracy of our DTA data. Ethephon treatment significantly increased fruit abscission and ethylene production of fruitlet. The possible molecular events to control the ethephon-promoted litchi fruitlet abscission were prompted out. The increased ethylene evolution in fruitlet would suppress the synthesis and polar transport of auxin and trigger abscission signaling. To the best of our knowledge, it is the first time to monitor the gene expression profile occurring in the FAZ-enriched pedicel during litchi fruit abscission induced by ethephon on the genome-wide level. This study will contribute to a better understanding for the molecular regulatory mechanism of fruit abscission in litchi. PMID:26217356
Integrated Risk Information System (IRIS)
Ethephon ; CASRN 16672 - 87 - 0 Human health assessment information on a chemical substance is included in the IRIS database only after a comprehensive review of toxicity data , as outlined in the IRIS assessment development process . Sections I ( Health Hazard Assessments for Noncarcinogenic Effect
Nahar, Kamrun; Kyndt, Tina; De Vleesschauwer, David; Höfte, Monica; Gheysen, Godelieve
2011-01-01
Complex defense signaling pathways, controlled by different hormones, are involved in the reaction of plants to a wide range of biotic and abiotic stress factors. We studied the ability of salicylic acid, jasmonate (JA), and ethylene (ET) to induce systemic defense in rice (Oryza sativa) against the root knot nematode Meloidogyne graminicola. Exogenous ET (ethephon) and JA (methyl jasmonate) supply on the shoots induced a strong systemic defense response in the roots, exemplified by a major up-regulation of pathogenesis-related genes OsPR1a and OsPR1b, while the salicylic acid analog BTH (benzo-1,2,3-thiadiazole-7-carbothioic acid S-methyl ester) was a less potent systemic defense inducer from shoot to root. Experiments with JA biosynthesis mutants and ET-insensitive transgenics showed that ET-induced defense requires an intact JA pathway, while JA-induced defense was still functional when ET signaling was impaired. Pharmacological inhibition of JA and ET biosynthesis confirmed that JA biosynthesis is needed for ET-induced systemic defense, and quantitative real-time reverse transcription-polymerase chain reaction data revealed that ET application onto the shoots strongly activates JA biosynthesis and signaling genes in the roots. All data provided in this study point to the JA pathway to play a pivotal role in rice defense against root knot nematodes. The expression of defense-related genes was monitored in root galls caused by M. graminicola. Different analyzed defense genes were attenuated in root galls caused by the nematode at early time points after infection. However, when the exogenous defense inducers ethephon and methyl jasmonate were supplied to the plant, the nematode was less effective in counteracting root defense pathways, hence making the plant more resistant to nematode infection. PMID:21715672
40 CFR 180.300 - Ethephon; tolerances for residues.
Code of Federal Regulations, 2013 CFR
2013-07-01
... 40 Protection of Environment 25 2013-07-01 2013-07-01 false Ethephon; tolerances for residues. 180.300 Section 180.300 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) PESTICIDE PROGRAMS TOLERANCES AND EXEMPTIONS FOR PESTICIDE CHEMICAL RESIDUES IN FOOD Specific Tolerances § 180.300...
Control of Western Dwarf Mistletoe with the plant-growth regulator Ethephon.
Catherine A. Parks; James T. Hoffman
1991-01-01
Ethephon (Ethrel), an ethylene-releasing plant-growth regulator, was applied with a hydraulic sprayer to ponderosa pine (Pinus ponderosa Dougl. ex Laws.) infected with dwarf mistletoe (Arceuthobium campylopodum Engelm. f. tsugense (Rosend.) Gill) in the Emmett Ranger District, Boise National Forest. Abscission rates of 60 to...
Alferez, Fernando; Pozo, Luis V; Rouseff, Russell R; Burns, Jacqueline K
2013-03-27
The effect of 5-chloro-3-methyl-4-nitro-1H-pyrazole (CMNP) and ethephon on peel color, flavedo carotenoid gene expression, and carotenoid accumulation was investigated in mature 'Valencia' orange ( Citrus sinensis L. Osbeck) fruit flavedo at three maturation stages. Abscission agent application altered peel color. CMNP was more effective than ethephon in promoting green-to-red (a) and blue-to-yellow (b) color at the middle and late maturation stages and total carotenoid changes at all maturation stages. Altered flow of carotenoid precursors during maturation due to abscission agents was suggested by changes in phytoene desaturase (Pds) and ζ-carotene desaturase (Zds) gene expression. However, each abscission agent affected downstream expression differentially. Ethephon application increased β-carotene hydroxilase (β-Chx) transcript accumulation 12-fold as maturation advanced from the early to middle and late stages. CMNP markedly increased β- and ε-lycopene cyclase (Lcy) transcript accumulation 45- and 15-fold, respectively, at midmaturation. Patterns of carotenoid accumulation in flavedo were supported in part by gene expression changes. CMNP caused greater accumulation of total flavedo carotenoids at all maturation stages when compared with ethephon or controls. In general, CMNP treatment increased total red carotenoids more than ethephon or the control but decreased total yellow carotenoids at each maturation stage. In control fruit flavedo, total red carotenoids increased and yellow carotenoids decreased as maturation progressed. Trends in total red carotenoids during maturation were consistent with measured a values. Changes in carotenoid accumulation and expression patterns in flavedo suggest that regulation of carotenoid accumulation is under transcriptional, translational, and post-translational control.
Chamkasem, Narong
2017-08-30
A simple high-throughput liquid chromatography/tandem mass spectrometry (LC-MS-MS) method was developed for the determination of maleic hydrazide, glyphosate, fosetyl aluminum, and ethephon in grapes using a reversed-phase column with weak anion-exchange and cation-exchange mixed mode. A 5 g test portion was shaken with 50 mM HOAc and 10 mM Na 2 EDTA in 1/3 (v/v) MeOH/H 2 O for 10 min. After centrifugation, the extract was passed through an Oasis HLB cartridge to retain suspended particulates and nonpolar interferences. The final solution was injected and directly analyzed in 17 min by LC-MS-MS. Two MS-MS transitions were monitored in the method for each target compound to achieve true positive identification. Four isotopically labeled internal standards corresponding to each analyte were used to correct for matrix suppression effects and/or instrument signal drift. The linearity of the detector response was demonstrated in the range from 10 to 1000 ng/mL for each analyte with a coefficient of determination (R 2 ) of ≥0.995. The average recovery for all analytes at 100, 500, and 2000 ng/g (n = 5) ranged from 87 to 111%, with a relative standard deviation of less than 17%. The estimated LOQs for maleic hydrazide, glyphosate, fosetyl-Al, and ethephon were 38, 19, 29, and 34 ng/g, respectively.
Whole Plant and Leaf Steady State Gas Exchange during Ethylene Exposure in Xanthium strumarium L. 1
Woodrow, Lorna; Jiao, Jirong; Tsujita, M. James; Grodzinski, Bernard
1989-01-01
The effects of ethylene evolved from ethephon on leaf and whole plant photosynthesis in Xanthium strumarium L. were examined. Ethylene-induced epinasty reduced light interception by the leaves of ethephon treated plants by up to 60%. Gas exchange values of individual, attached leaves under identical assay conditions were not inhibited even after 36 hours of ethylene exposure, although treated leaves required a longer induction period to achieve steady state photosynthesis. The speed of translocation of recently fixed 11C-assimilate movement was not seriously impaired following ethephon treatment; however, a greater proportion of the assimilate was partitioned downward toward the roots. Within 24 hours of ethephon treatment, the whole plant net carbon exchange rate expressed on a per plant basis or a leaf area basis had dropped by 35%. The apparent inhibition of net carbon exchange rate was reversed by physically repositioning the leaves with respect to the light source. Ethylene exposure also inhibited expansion of young leaves which was partially reversed when the leaves were repositioned. The data indicated that ethylene indirectly affected net C gain and plant growth through modification of light interception and altered sink demand without directly inhibiting leaf photosynthesis. Images Figure 1 PMID:16666773
Whole Plant and Leaf Steady State Gas Exchange during Ethylene Exposure in Xanthium strumarium L.
Woodrow, L; Jiao, J; Tsujita, M J; Grodzinski, B
1989-05-01
The effects of ethylene evolved from ethephon on leaf and whole plant photosynthesis in Xanthium strumarium L. were examined. Ethylene-induced epinasty reduced light interception by the leaves of ethephon treated plants by up to 60%. Gas exchange values of individual, attached leaves under identical assay conditions were not inhibited even after 36 hours of ethylene exposure, although treated leaves required a longer induction period to achieve steady state photosynthesis. The speed of translocation of recently fixed (11)C-assimilate movement was not seriously impaired following ethephon treatment; however, a greater proportion of the assimilate was partitioned downward toward the roots. Within 24 hours of ethephon treatment, the whole plant net carbon exchange rate expressed on a per plant basis or a leaf area basis had dropped by 35%. The apparent inhibition of net carbon exchange rate was reversed by physically repositioning the leaves with respect to the light source. Ethylene exposure also inhibited expansion of young leaves which was partially reversed when the leaves were repositioned. The data indicated that ethylene indirectly affected net C gain and plant growth through modification of light interception and altered sink demand without directly inhibiting leaf photosynthesis.
NASA Technical Reports Server (NTRS)
Takahashi, H.; Jaffe, M. J.
1984-01-01
The present study was designed to establish the role of an essential hormone controlling sex expression in cucumber. A potent anti-ethylene agent, AgNO3, completely inhibited pistillate flower formation caused by IAA, ACC or ethephon. Inhibitors of ethylene biosynthesis, AVG and CoCl2 also suppressed feminization due to exogenous IAA or ACC. Though AVG also suppressed ethephon-induced feminization, this may be due to the second effect of AVG rather than the effect on ACC biosynthesis. These results confirm that ethylene is a major factor regulating feminization and that exogenous auxin induces pistillate flower formation through its stimulation of ethylene production, rather than ACC production.
Thomas Nicholls
2009-01-01
This is a summary of the 25-year history of studies of mammal and bird vectors of lodgepole pine dwarf mistletoe (Arceuthobium americanum), ethephon control of dwarf mistletoe, and the ecology of the most important dwarf mistletoe vector, the gray jay (Persisoreus canadensis), on the USDA Forest Service, Fraser Experimental Forest...
Iqbal, Noushina; Umar, Shahid; Per, Tasir S; Khan, Nafees A
2017-05-04
Salinity is a serious threat to plant growth and development worldwide reducing agricultural productivity each year. Ethylene is an important phytohormone that affects plants performance under normal and abiotic stress conditions. In this study, role of ethylene was investigated in mitigating salinity stress (100 mM NaCl) effects on photosynthesis in mustard plants subjected to different nitrogen (N; 5 and 10 mM) levels. Plants under salinity stress exhibited marked increase in proline and reduced glutathione (GSH) content and activity of antioxidant enzymes. Nitrogen supplementation at 10 mM was better than 200 µl l -1 ethephon treatment under no stress. However, under salinity stress, both N and ethephon were equally effective. The combined application of 10 mM N and ethephon to salinity stressed plants produced greatest increase in photosynthesis by increasing proline and antioxidant metabolism. Ethylene evolution was high under salinity stress, but treatment of 10 mM N and 200 µl l -1 ethephon greatly decreased ethylene evolution that was equivalent to the 10 mM N treatment alone. This concentration of ethylene decreased the oxidative stress and increased the photosynthetic nitrogen use efficiency (NUE) maximally to increase photosynthesis. The use of ethylene action inhibitor, norbornadiene (NBD) showed reduction in ethylene mediated effects in alleviating salinity. Norbornadiene decreased the photosynthetic-NUE, proline and GSH content that resulted in decrease in photosynthesis under salinity stress. This study indicated that ethylene regulated the proline and antioxidant metabolism under salinity stress to increase photosynthetic functions of mustard grown with low and optimum N. The modulation of ethylene could be adopted in agricultural practices to increase photosynthesis under salinity stress.
Characterization and expression profiles of MaACS and MaACO genes from mulberry (Morus alba L.)*
Liu, Chang-ying; Lü, Rui-hua; Li, Jun; Zhao, Ai-chun; Wang, Xi-ling; Diane, Umuhoza; Wang, Xiao-hong; Wang, Chuan-hong; Yu, Ya-sheng; Han, Shu-mei; Lu, Cheng; Yu, Mao-de
2014-01-01
1-Aminocyclopropane-1-carboxylic acid synthase (ACS) and 1-aminocyclopropane-1-carboxylic acid oxidase (ACO) are encoded by multigene families and are involved in fruit ripening by catalyzing the production of ethylene throughout the development of fruit. However, there are no reports on ACS or ACO genes in mulberry, partly because of the limited molecular research background. In this study, we have obtained five ACS gene sequences and two ACO gene sequences from Morus Genome Database. Sequence alignment and phylogenetic analysis of MaACO1 and MaACO2 showed that their amino acids are conserved compared with ACO proteins from other species. MaACS1 and MaACS2 are type I, MaACS3 and MaACS4 are type II, and MaACS5 is type III, with different C-terminal sequences. Quantitative reverse transcriptase polymerase chain reaction (qRT-PCR) expression analysis showed that the transcripts of MaACS genes were strongly expressed in fruit, and more weakly in other tissues. The expression of MaACO1 and MaACO2 showed different patterns in various mulberry tissues. MaACS and MaACO genes demonstrated two patterns throughout the development of mulberry fruit, and both of them were strongly up-regulated by abscisic acid (ABA) and ethephon. PMID:25001221
Liu, Chuan-He; Fan, Chao
2016-01-01
A remarkable characteristic of pineapple is its ability to undergo floral induction in response to external ethylene stimulation. However, little information is available regarding the molecular mechanism underlying this process. In this study, the differentially expressed genes (DEGs) in plants exposed to 1.80 mL·L−1 (T1) or 2.40 mL·L−1 ethephon (T2) compared with Ct plants (control, cleaning water) were identified using RNA-seq and gene expression profiling. Illumina sequencing generated 65,825,224 high-quality reads that were assembled into 129,594 unigenes with an average sequence length of 1173 bp. Of these unigenes, 24,775 were assigned to specific KEGG pathways, of which metabolic pathways and biosynthesis of secondary metabolites were the most highly represented. Gene Ontology (GO) analysis of the annotated unigenes revealed that the majority were involved in metabolic and cellular processes, cell and cell part, catalytic activity and binding. Gene expression profiling analysis revealed 3788, 3062, and 758 DEGs in the comparisons of T1 with Ct, T2 with Ct, and T2 with T1, respectively. GO analysis indicated that these DEGs were predominantly annotated to metabolic and cellular processes, cell and cell part, catalytic activity, and binding. KEGG pathway analysis revealed the enrichment of several important pathways among the DEGs, including metabolic pathways, biosynthesis of secondary metabolites and plant hormone signal transduction. Thirteen DEGs were identified as candidate genes associated with the process of floral induction by ethephon, including three ERF-like genes, one ETR-like gene, one LTI-like gene, one FT-like gene, one VRN1-like gene, three FRI-like genes, one AP1-like gene, one CAL-like gene, and one AG-like gene. qPCR analysis indicated that the changes in the expression of these 13 candidate genes were consistent with the alterations in the corresponding RPKM values, confirming the accuracy and credibility of the RNA-seq and gene expression profiling results. Ethephon-mediated induction likely mimics the process of vernalization in the floral transition in pineapple by increasing LTI, FT, and VRN1 expression and promoting the up-regulation of floral meristem identity genes involved in flower development. The candidate genes screened can be used in investigations of the molecular mechanisms of the flowering pathway and of various other biological mechanisms in pineapple. PMID:26955375
Luang, Sukanya; Cho, Jung-Il; Mahong, Bancha; Opassiri, Rodjana; Akiyama, Takashi; Phasai, Kannika; Komvongsa, Juthamath; Sasaki, Nobuhiro; Hua, Yan-ling; Matsuba, Yuki; Ozeki, Yoshihiro; Jeon, Jong-Seong; Cairns, James R. Ketudat
2013-01-01
Glycosylation is an important mechanism of controlling the reactivities and bioactivities of plant secondary metabolites and phytohormones. Rice (Oryza sativa) Os9BGlu31 is a glycoside hydrolase family GH1 transglycosidase that acts to transfer glucose between phenolic acids, phytohormones, and flavonoids. The highest activity was observed with the donors feruloyl-glucose, 4-coumaroyl-glucose, and sinapoyl-glucose, which are known to serve as donors in acyl and glucosyl transfer reactions in the vacuole, where Os9BGlu31 is localized. The free acids of these compounds also served as the best acceptors, suggesting that Os9BGlu31 may equilibrate the levels of phenolic acids and carboxylated phytohormones and their glucoconjugates. The Os9BGlu31 gene is most highly expressed in senescing flag leaf and developing seed and is induced in rice seedlings in response to drought stress and treatment with phytohormones, including abscisic acid, ethephon, methyljasmonate, 2,4-dichlorophenoxyacetic acid, and kinetin. Although site-directed mutagenesis of Os9BGlu31 indicated a function for the putative catalytic acid/base (Glu169), catalytic nucleophile residues (Glu387), and His386, the wild type enzyme displays an unusual lack of inhibition by mechanism-based inhibitors of GH1 β-glucosidases that utilize a double displacement retaining mechanism. PMID:23430256
Cloning and characterization of a novel NAC family gene CarNAC1 from chickpea (Cicer arietinum L.).
Peng, Hui; Yu, Xingwang; Cheng, Huiying; Shi, Qinghua; Zhang, Hua; Li, Jiangui; Ma, Hao
2010-01-01
The plant-specific NAC (for NAM, ATAF1,2 and CUC2) proteins have been found to play important roles in plant development and stress responses. In this study, a NAC gene CarNAC1 (for Cicer arietinum L. NAC gene 1) was isolated from a cDNA library constructed with chickpea seedling leaves treated by polyethylene glycol. CarNAC1 encoded a putative protein with 239 amino acids and contained 3 exons and 2 introns within genomic DNA sequence. CarNAC1 had a conserved NAC domain in the N-terminus and the CarNAC1:GFP (green fluorescent protein) fusion protein was localized in the nucleus of onion epidermal cells. Additionally, CarNAC1 exhibited the trans-activation activity which was mapped to the C-terminus. The CarNAC1 transcript was detected in many chickpea organs including seedling leaves, stems, roots, flowers, and young pods, but less accumulated in young seeds. CarNAC1 was induced by leaf age and showed changes in expression during seed development and germination. Furthermore, the expression of CarNAC1 was strongly induced by drought, salt, cold, wounding, H(2)O(2), ethephon, salicylic acid, indole-3-acetic acid, and gibberellin. Our results suggest that CarNAC1 encodes a novel NAC-domain protein and may be a transcriptional activator involved in plant development and various stress responses.
Balaguera-López, Helber E; Espinal-Ruiz, Mauricio; Zacarías, Lorenzo; Herrera, Aníbal O
2017-01-01
Cape gooseberry (Physalis peruviana L.) fruits are highly perishable berries that exhibit a climacteric respiratory behavior. The objective of this study was to evaluate the effect of ethylene and the ethylene action inhibitor 1-methylcyclopropene on the postharvest behavior of cape gooseberry fruits (ecotype Colombia). Fruits were treated with ethylene, in an ethephon application (1000 µL L -1 ), and pretreated with 1-methylcyclopropene (1 µL L -1 ), 1-methylcyclopropene+ethylene, and results compared with a control without application. Subsequently, the fruits were maintained at room temperature (20 ℃, 75% RH) for up to 11 days. The pretreatment of the cape gooseberry fruits with 1-methylcyclopropene delayed most of the ripening-associated parameters, with a reduction in the respiration rate and ethylene production, skin color development, total soluble solids, total carotenoid content, loss of firmness, loss of total titratable acidity and emission of volatile compounds such as ethyl octanoate, ethyl butanoate, ethyl decanoate, and hexyl decanoate. Conversely, application of ethephon accelerated most of these physiological changes and also overcame most of the effects prevented by the ethylene action inhibitor. Altogether, the results supported the idea of a climacteric-like behavior for cape gooseberry fruits and pointing out that the pretreatment with 1-methylcyclopropene may be a promising and efficient postharvest treatment to delay maturity and extend the postharvest period. © The Author(s) 2016.
Li, Yun-He; Wu, Qing-Song; Huang, Xia; Liu, Sheng-Hui; Zhang, Hong-Na; Zhang, Zhi; Sun, Guang-Ming
2016-01-01
Exogenous ethylene, or ethephon, has been widely used to induce pineapple flowering, but the molecular mechanism behind ethephon induction is still unclear. In this study, we cloned four genes encoding ethylene receptors (designated AcERS1a, AcERS1b, AcETR2a, and AcETR2b). The 5' flanking sequences of these four genes were also cloned by self-formed adaptor PCR and SiteFinding-PCR, and a group of putative cis-acting elements was identified. Phylogenetic tree analysis indicated that AcERS1a, AcERS1b, AcETR2a, and AcETR2b belonged to the plant ERS1s and ETR2/EIN4-like groups. Quantitative real-time PCR showed that AcETR2a and AcETR2b (subfamily 2) were more sensitive to ethylene treatment compared with AcERS1a and AcERS1b (subfamily 1). The relative expression of AcERS1b, AcETR2a, and AcETR2b was significantly increased during the earlier period of pineapple inflorescence formation, especially at 1-9 days after ethylene treatment (DAET), whereas AcERS1a expression changed less than these three genes. In situ hybridization results showed that bract primordia (BP) and flower primordia (FP) appeared at 9 and 21 DAET, respectively, and flowers were formed at 37 DAET. AcERS1a, AcERS1b, AcETR2a, and AcETR2b were mainly expressed in the shoot apex at 1-4 DAET; thereafter, with the appearance of BP and FP, higher expression of these genes was found in these new structures. Finally, at 37 DAET, the expression of these genes was mainly focused in the flower but was also low in other structures. These findings indicate that these four ethylene receptor genes, especially AcERS1b, AcETR2a, and AcETR2b, play important roles during pineapple flowering induced by exogenous ethephon.
Li, Yun-He; Wu, Qing-Song; Huang, Xia; Liu, Sheng-Hui; Zhang, Hong-Na; Zhang, Zhi; Sun, Guang-Ming
2016-01-01
Exogenous ethylene, or ethephon, has been widely used to induce pineapple flowering, but the molecular mechanism behind ethephon induction is still unclear. In this study, we cloned four genes encoding ethylene receptors (designated AcERS1a, AcERS1b, AcETR2a, and AcETR2b). The 5′ flanking sequences of these four genes were also cloned by self-formed adaptor PCR and SiteFinding-PCR, and a group of putative cis-acting elements was identified. Phylogenetic tree analysis indicated that AcERS1a, AcERS1b, AcETR2a, and AcETR2b belonged to the plant ERS1s and ETR2/EIN4-like groups. Quantitative real-time PCR showed that AcETR2a and AcETR2b (subfamily 2) were more sensitive to ethylene treatment compared with AcERS1a and AcERS1b (subfamily 1). The relative expression of AcERS1b, AcETR2a, and AcETR2b was significantly increased during the earlier period of pineapple inflorescence formation, especially at 1–9 days after ethylene treatment (DAET), whereas AcERS1a expression changed less than these three genes. In situ hybridization results showed that bract primordia (BP) and flower primordia (FP) appeared at 9 and 21 DAET, respectively, and flowers were formed at 37 DAET. AcERS1a, AcERS1b, AcETR2a, and AcETR2b were mainly expressed in the shoot apex at 1–4 DAET; thereafter, with the appearance of BP and FP, higher expression of these genes was found in these new structures. Finally, at 37 DAET, the expression of these genes was mainly focused in the flower but was also low in other structures. These findings indicate that these four ethylene receptor genes, especially AcERS1b, AcETR2a, and AcETR2b, play important roles during pineapple flowering induced by exogenous ethephon. PMID:27252725
Malladi, Anish; Burns, Jacqueline K
2008-01-01
Understanding leaf and fruit abscission is essential in order to develop strategies for controlling the process in fruit crops. Mechanisms involved in signalling leaf and fruit abscission upon induction by abscission agents were investigated in Citrus sinensis cv. 'Valencia'. Previous studies have suggested a role for phospholipid signalling; hence, two phospholipase D cDNA sequences, CsPLDalpha1 and CsPLDgamma1, were isolated and their role was examined. CsPLDalpha1 expression was reduced in leaves but unaltered in fruit peel tissue treated with an ethylene-releasing compound (ethephon), or a fruit-specific abscission agent, 5-chloro-3-methyl-4-nitro-1H-pyrazole (CMNP). By contrast, CsPLDgamma1 expression was up-regulated within 6 h (leaves) and 24 h (fruit peel) after treatment with ethephon or CMNP, respectively. CsPLDalpha1 expression was diurnally regulated in leaf blade but not fruit peel. CsPLDgamma1 exhibited strong diurnal oscillation in expression in leaves and fruit peel with peak expression around midday. While diurnal fluctuation in CsPLDalpha1 expression appeared to be light-entrained in leaves, CsPLDgamma1 expression was regulated by light and the circadian clock. The diurnal expression of both genes was modulated by ethylene-signalling. The ethephon-induced leaf abscission and the ethephon- and CMNP-induced decrease in fruit detachment force were enhanced by application during rising diurnal expression of CsPLDgamma1. The results indicate differential regulation of CsPLDalpha1 and CsPLDgamma1 in leaves and fruit, and suggest possible roles for PLD-dependent signalling in regulating abscission responses in citrus.
Malladi, Anish; Burns, Jacqueline K.
2008-01-01
Understanding leaf and fruit abscission is essential in order to develop strategies for controlling the process in fruit crops. Mechanisms involved in signalling leaf and fruit abscission upon induction by abscission agents were investigated in Citrus sinensis cv. ‘Valencia’. Previous studies have suggested a role for phospholipid signalling; hence, two phospholipase D cDNA sequences, CsPLDα1 and CsPLDγ1, were isolated and their role was examined. CsPLDα1 expression was reduced in leaves but unaltered in fruit peel tissue treated with an ethylene-releasing compound (ethephon), or a fruit-specific abscission agent, 5-chloro-3-methyl-4-nitro-1H-pyrazole (CMNP). By contrast, CsPLDγ1 expression was up-regulated within 6 h (leaves) and 24 h (fruit peel) after treatment with ethephon or CMNP, respectively. CsPLDα1 expression was diurnally regulated in leaf blade but not fruit peel. CsPLDγ1 exhibited strong diurnal oscillation in expression in leaves and fruit peel with peak expression around midday. While diurnal fluctuation in CsPLDα1 expression appeared to be light-entrained in leaves, CsPLDγ1 expression was regulated by light and the circadian clock. The diurnal expression of both genes was modulated by ethylene-signalling. The ethephon-induced leaf abscission and the ethephon- and CMNP-induced decrease in fruit detachment force were enhanced by application during rising diurnal expression of CsPLDγ1. The results indicate differential regulation of CsPLDα1 and CsPLDγ1 in leaves and fruit, and suggest possible roles for PLD-dependent signalling in regulating abscission responses in citrus. PMID:18799715
Auxin-Induced Ethylene Triggers Abscisic Acid Biosynthesis and Growth Inhibition1
Hansen, Hauke; Grossmann, Klaus
2000-01-01
The growth-inhibiting effects of indole-3-acetic acid (IAA) at high concentration and the synthetic auxins 7-chloro-3-methyl-8-quinolinecarboxylic acid (quinmerac), 2-methoxy-3,6-dichlorobenzoic acid (dicamba), 4-amino-3,6,6-trichloropicolinic acid (picloram), and naphthalene acetic acid, were investigated in cleavers (Galium aparine). When plants were root treated with 0.5 mm IAA, shoot epinasty and inhibition of root and shoot growth developed during 24 h. Concomitantly, 1-aminocyclopropane-1-carboxylic acid (ACC) synthase activity, and ACC and ethylene production were transiently stimulated in the shoot tissue within 2 h, followed by increases in immunoreactive (+)-abscisic acid (ABA) and its precursor xanthoxal (xanthoxin) after 5 h. After 24 h of treatment, levels of xanthoxal and ABA were elevated up to 2- and 24-fold, relative to control, respectively. In plants treated with IAA, 7-chloro-3-methyl-8-quinolinecarboxylic acid, naphthalene acetic acid, 2-methoxy-3,6-dichlorobenzoic acid, and 4-amino-3,6,6-trichloropicolinic acid, levels of ethylene, ACC, and ABA increased in close correlation with inhibition of shoot growth. Aminoethoxyvinyl-glycine and cobalt ions, which inhibit ethylene synthesis, decreased ABA accumulation and growth inhibition, whereas the ethylene-releasing ethephon promoted ABA levels and growth inhibition. In accordance, tomato mutants defective in ethylene perception (never ripe) did not produce the xanthoxal and ABA increases and growth inhibition induced by auxins in wild-type plants. This suggests that auxin-stimulated ethylene triggers ABA accumulation and the consequent growth inhibition. Reduced catabolism most probably did not contribute to ABA increase, as indicated by immunoanalyses of ABA degradation and conjugation products in shoot tissue and by pulse experiments with [3H]-ABA in cell suspensions of G. aparine. In contrast, studies using inhibitors of ABA biosynthesis (fluridone, naproxen, and tungstate), ABA-deficient tomato mutants (notabilis, flacca, and sitiens), and quantification of xanthophylls indicate that ABA biosynthesis is influenced, probably through stimulated cleavage of xanthophylls to xanthoxal in shoot tissue. PMID:11080318
Auxin-induced ethylene triggers abscisic acid biosynthesis and growth inhibition.
Hansen, H; Grossmann, K
2000-11-01
The growth-inhibiting effects of indole-3-acetic acid (IAA) at high concentration and the synthetic auxins 7-chloro-3-methyl-8-quinolinecarboxylic acid (quinmerac), 2-methoxy-3,6-dichlorobenzoic acid (dicamba), 4-amino-3,6, 6-trichloropicolinic acid (picloram), and naphthalene acetic acid, were investigated in cleavers (Galium aparine). When plants were root treated with 0.5 mM IAA, shoot epinasty and inhibition of root and shoot growth developed during 24 h. Concomitantly, 1-aminocyclopropane-1-carboxylic acid (ACC) synthase activity, and ACC and ethylene production were transiently stimulated in the shoot tissue within 2 h, followed by increases in immunoreactive (+)-abscisic acid (ABA) and its precursor xanthoxal (xanthoxin) after 5 h. After 24 h of treatment, levels of xanthoxal and ABA were elevated up to 2- and 24-fold, relative to control, respectively. In plants treated with IAA, 7-chloro-3-methyl-8-quinolinecarboxylic acid, naphthalene acetic acid, 2-methoxy-3,6-dichlorobenzoic acid, and 4-amino-3,6,6-trichloropicolinic acid, levels of ethylene, ACC, and ABA increased in close correlation with inhibition of shoot growth. Aminoethoxyvinyl-glycine and cobalt ions, which inhibit ethylene synthesis, decreased ABA accumulation and growth inhibition, whereas the ethylene-releasing ethephon promoted ABA levels and growth inhibition. In accordance, tomato mutants defective in ethylene perception (never ripe) did not produce the xanthoxal and ABA increases and growth inhibition induced by auxins in wild-type plants. This suggests that auxin-stimulated ethylene triggers ABA accumulation and the consequent growth inhibition. Reduced catabolism most probably did not contribute to ABA increase, as indicated by immunoanalyses of ABA degradation and conjugation products in shoot tissue and by pulse experiments with [(3)H]-ABA in cell suspensions of G. aparine. In contrast, studies using inhibitors of ABA biosynthesis (fluridone, naproxen, and tungstate), ABA-deficient tomato mutants (notabilis, flacca, and sitiens), and quantification of xanthophylls indicate that ABA biosynthesis is influenced, probably through stimulated cleavage of xanthophylls to xanthoxal in shoot tissue.
Transient Overexpression of HvSERK2 Improves Barley Resistance to Powdery Mildew.
Li, Yingbo; Li, Qingwei; Guo, Guimei; He, Ting; Gao, Runhong; Faheem, Muhammad; Huang, Jianhua; Lu, Ruiju; Liu, Chenghong
2018-04-18
Somatic embryogenesis receptor-like kinases (SERKs) play an essential role in plant response to pathogen infection. Here we identified three SERK genes ( HvSERK1/2/3 ) from barley, and aimed to determine their implication in defense responses to barley powdery mildew ( Bgh ). Although HvSERK1/2/3 share the characteristic domains of the SERK family, only HvSERK2 was significantly induced in barley leaves during Bgh infection. The expression of HvSERK2 was rapidly induced by hydrogen peroxide (H₂O₂) treatment, but not by treatment with salicylic acid (SA), methyl jasmonate (MeJA), ethephon (ETH), or abscisic acid (ABA). Bioinformatics analysis of the cloned HvSERK2 promoter revealed that it contains several elements responsible for defense responses against pathogens. Promoter functional analysis showed that the HvSERK2 promoter was induced by Bgh and H₂O₂. Subcellular localization analysis of HvSERK2 indicated that it is mainly located on the plasma membrane. Transient overexpression of HvSERK2 in epidermal cells of the susceptible barley cultivar Hua 30 reduced the Bgh haustorium index from 58.6% to 43.2%. This study suggests that the HvSERK2 gene plays a positive role in the improvement of barley resistance to powdery mildew, and provides new insight into the function of SERK genes in the biotic stress response of plants.
40 CFR 180.300 - Ethephon; tolerances for residues.
Code of Federal Regulations, 2010 CFR
2010-07-01
... Blackberry 30.0 Blueberry 20.0 Cantaloupe 2.0 Cattle, fat 0.02 Cattle, kidney 1.0 Cattle, meat 0.02 Cattle, meat byproducts, except kidney 0.2 Cherry 10.0 Coffee, bean, green 0.5 Cotton, gin byproducts 180.0 Cotton, undelinted seed 6.0 Cucumber 0.1 Egg 0.002 Goat, fat 0.02 Goat, kidney 1.0 Goat, meat 0.02 Goat...
40 CFR 180.300 - Ethephon; tolerances for residues.
Code of Federal Regulations, 2011 CFR
2011-07-01
... Blackberry 30.0 Blueberry 20.0 Cantaloupe 2.0 Cattle, fat 0.02 Cattle, kidney 1.0 Cattle, meat 0.02 Cattle, meat byproducts, except kidney 0.2 Cherry 10.0 Coffee, bean, green 0.5 Cotton, gin byproducts 180.0 Cotton, undelinted seed 6.0 Cucumber 0.1 Egg 0.002 Goat, fat 0.02 Goat, kidney 1.0 Goat, meat 0.02 Goat...
Identification of jasmonic acid and its methyl ester as gum-inducing factors in tulips.
Skrzypek, Edyta; Miyamoto, Kensuke; Saniewski, Marian; Ueda, Junichi
2005-02-01
The purpose of this study was to identify endogenous factors that induce gummosis and to show their role in gummosis in tulip (Tulipa gesneriana L. cv. Apeldoorn) stems. Using procedures to detect endogenous factors that induce gum in the stem of tulips, jasmonic acid (JA) and methyl jasmonate (JA-Me) were successfully identified using gas-liquid chromatography-mass spectrometry. Total amounts of JA and JA-Me designated as jasmonates in tulip stems were also estimated at about 70-80 ng/g fresh weight, using deuterium-labeled jasmonates as internal standards. The application of JA and JA-Me as lanolin pastes substantially induced gums in tulip stems with ethylene production. The application of ethephon, an ethylene-generating compound, however, induced no gummosis although it slightly affected jasmonate content in tulip stems. These results strongly suggest that JA and JA-Me are endogenous factors that induce gummosis in tulip stems.
Wang, Yonglin; Xiong, Dianguang; Jiang, Ning; Li, Xuewu; Yang, Qiqing; Tian, Chengming
2016-01-01
Arceuthobium (dwarf mistletoes) are hemiparasites that may cause great damage to infected trees belonging to Pinaceae and Cupressaceae. Currently, dwarf mistletoe control involves the use of the ethylene-producing product ethephon (ETH), which acts by inducing dwarf mistletoe shoot abscission. However, the process by which ETH functions is mostly unknown. Therefore, the transcriptome of the ETH-exposed plants was compared to non-exposed controls to identify genes associated with the response to ethephon. In this study, the reference transcriptome was contained 120,316 annotated unigenes, with a total of 21,764 ETH-responsive differentially expressed unigenes were identified. These ETH-associated genes clustered into 20 distinctly expressed pattern groups, providing a view of molecular events with good spatial and temporal resolution. As expected, the greatest number of unigenes with changed expression were observed at the onset of abscission, suggesting induction by ethylene. ETH also affected genes associated with shoot abscission processes including hormone biosynthesis and signaling, cell wall hydrolysis and modification, lipid transference, and more. The comprehensive transcriptome data set provides a wealth of genomic resources for dwarf mistletoe communities and contributes to a better understanding of the molecular regulatory mechanism of ethylene-caused shoots abscission. PMID:27941945
Improving field production of ergot alkaloids by application of gametocide on rye host plants.
Hanosová, Helena; Koprna, Radoslav; Valík, Josef; Knoppová, Lucie; Frébort, Ivo; Dzurová, Lenka; Galuszka, Petr
2015-12-25
Ergot alkaloids are widely used in the pharmaceutical industry in drug preparations for treating migraines and Parkinson's disease, inducing uterine contraction, and other purposes. Phytopathogenic fungi of the genus Claviceps (e.g. C. purpurea) comprise a major biological source of ergot alkaloids. Worldwide industrial production of these alkaloids derives almost equally from two biotechnological procedures: submerged culture of the fungus in fermenters and field parasitic production in dormant fungal organs known as sclerotia (also termed ergot). Ergot yields from field cultivation are greatly affected by weather and also can be much reduced by pollen contamination from imperfectly male-sterile rye, as only unfertilized ovaries can be infected by C. purpurea spores. Two substances with gametocidal effect - maleic hydrazide and 2-chloroethylphosphonic acid - were tested during three consecutive seasons in small field experiments for the ability to induce or amplify the male sterility of rye as well as the impacts on germination of C. purpurea spores and general vitality of rye host plants. Maleic hydrazide was proven to be a highly effective gametocide on both a fertile rye variety and a variety with imperfectly induced cytoplasmic male sterility. It showed negligible effect on germination of C. purpurea spores. Both accurate dosaging of the active gametocidal compound and timing of the application just 2-3 weeks before onset of anthesis proved crucial to achieving high ergot yield with minimum grain impurities. Copyright © 2015 Elsevier B.V. All rights reserved.
Stotz, Henrik U.; Pittendrigh, Barry R.; Kroymann, Jürgen; Weniger, Kerstin; Fritsche, Jacqueline; Bauke, Antje; Mitchell-Olds, Thomas
2000-01-01
The induction of plant defenses by insect feeding is regulated via multiple signaling cascades. One of them, ethylene signaling, increases susceptibility of Arabidopsis to the generalist herbivore Egyptian cotton worm (Spodoptera littoralis; Lepidoptera: Noctuidae). The hookless1 mutation, which affects a downstream component of ethylene signaling, conferred resistance to Egyptian cotton worm as compared with wild-type plants. Likewise, ein2, a mutant in a central component of the ethylene signaling pathway, caused enhanced resistance to Egyptian cotton worm that was similar in magnitude to hookless1. Moreover, pretreatment of plants with ethephon (2-chloroethanephosphonic acid), a chemical that releases ethylene, elevated plant susceptibility to Egyptian cotton worm. By contrast, these mutations in the ethylene-signaling pathway had no detectable effects on diamondback moth (Plutella xylostella) feeding. It is surprising that this is not due to nonactivation of defense signaling, because diamondback moth does induce genes that relate to wound-response pathways. Of these wound-related genes, jasmonic acid regulates a novel β-glucosidase 1 (BGL1), whereas ethylene controls a putative calcium-binding elongation factor hand protein. These results suggest that a specialist insect herbivore triggers general wound-response pathways in Arabidopsis but, unlike a generalist herbivore, does not react to ethylene-mediated physiological changes. PMID:11080278
Control of Abscission in Agricultural Crops and Its Physiological Basis 1
Cooper, W. C.; Rasmussen, G. K.; Rogers, B. J.; Reece, P. C.; Henry, W. H.
1968-01-01
Some naphthalene and phenoxy compounds prevent preharvest drop of apples, pears, and citrus fruits. These studies have been complicated by an unrecognized high level of ethylene produced by leaves and fruit on trees sprayed with these growth regulators. An apparent contradiction is the effectiveness of both 2,4-dichlorophenoxyacetic acid and n-dimethylaminosuccinamic acid (a growth retardant which retards biosynthesis of auxin) in preventing abscission of apples. Thus, in the presence of low auxin concentrations in the tissue, this growth retardant prevents fruit abscission even more effectively than 2,4-dichlorophenoxyacetic acid at high auxin concentrations in the tissue. This anomaly is clarified on the basis that n-dimethylaminosuccinamic acid, in the presence of a known low ethylene biosynthesis, delays maturity of the fruit and thus prevents fruit abscission. On the other hand, 2,4-dichlorophenoxyacetic acid prevents abscission by direct growth hormone action, in spite of the side effects of ethylene production which speeds ripening of the fruit. With the promotion of abscission of leaves and fruit of agricultural crops, attention is given to the use of chemicals which induce ethylene production when applied to the plant, but which have no growth promotion effect to retard abscission. We can distinguish 5 kinds of such chemicals. One group includes gibberellic and abscisic acids that induce treated leaves to produce ethylene and abscise (under certain circumstances). However, they do not induce ethylene production by fruit and do not promote fruit abscission. A second group includes ascorbic acid, which, when used at relatively high levels, induces fruit to produce enough ethylene to promote abscission. Ascorbic acid-treated leaves also produce ethylene but not enough to cause much defoliation. A third group includes protein-synthesis inhibitors, such as cycloheximide. When low concentrations (about 30 μmoles/l) are sprayed on the fruit, the rapid effect of the freely moving ethylene (produced by the treated fruit) appears to mask temporarily any potential effect of the slowly moving inhibitor. A fourth group includes 2-chloroethylphosphonic and cupric ethylenediaminetetracetic acids, which induce ethylene production of fruit and leaves; production by leaves is substantially greater than by fruit and substantial defoliation results. A fifth group includes the cotton defoliation chemicals which clearly produce ethylene primarily as a result of chemical injury to the leaf blade. Another group of compounds, represented by beta-hydroxyethylhydrazine, produces ethylene by a chemical reaction with formaldehyde and water, and the presence of leaves or fruit is not required. At this time we are unaware of how chemicals in groups one to four act to promote ethylene evolution in leaves and fruit, but possible biological and chemical paths of ethylene production are discussed. Images PMID:16657019
Effects of Ethylene on Seed Germination of Halophyte Plants Under Salt Stress.
Li, Weiqiang; Tran, Lam-Son Phan
2017-01-01
Halophyte plant species are those that can finish their life cycle in the presence of 50% or more seawater concentration. Ethylene, as a natural plant hormone produced at later stages of seed germination, plays an important role in regulating seed germination. However, its regulatory role in seed dormancy and germination of halophyte plants under salt stress is still not well understood. In this chapter, we describe methods used for applications of two ethylene donors, ethephon and 1-aminocyclopropane-1-carboxylic acid, in studies aimed at examining the effects of ethylene on seed germination of a representative halophyte plant Suaeda salsa under high salinity. Similar approaches can be applied to the study of ethylene and salt interactions in other plant species, when taking into account that salt sensitivities may differ.
Wu, Zhencai; Burns, Jacqueline K
2004-07-01
beta-galactosidases have been detected in a wide range of plants and are characterized by their ability to hydrolyse terminal non-reducing beta-D-galactosyl residues from beta-D-galactosides. These enzymes have been detected in a wide range of plant organs and tissues. In a search for differentially expressed genes during the abscission process in citrus, sequences encoding beta-galactosidase were identified. Three cDNA fragments of a beta-galactosidase gene were isolated from a cDNA subtraction library constructed from mature fruit abscission zones 48 h after the application of a mature fruit-specific abscission agent, 5-chloro-3-methyl-4-nitro-1H-pyrazole (CMN-pyrazole). Based on sequence information derived from these fragments, a full-length cDNA of 2847 nucleotides (GenBank accession number AY029198) encoding beta-galactosidase was isolated from mature fruit abscission zones by 5'- and 3'-RACE approaches. The beta-galactosidase cDNA encoded a protein of 737 amino acid residues with a calculated molecular weight of 82 kDa. The deduced protein was highly homologous to plant beta-galactosidases expressed in fruit ripening. Southern blot analysis demonstrated that at least two closely related beta-galactosidase genes were present in 'Valencia' orange. Temporal expression patterns in mature fruit abscission zones indicated beta-galactosidase mRNA was detected 48 h after treatment of CMN-pyrazole and ethephon in mature fruit abscission zones. beta-galactosidase transcripts were detected in leaf abscission zones only after ethephon application. The citrus beta-galactosidase was expressed in stamens and petals of fully opened flowers and young fruitlets. The results suggest that this beta-galactosidase may play a role during abscission as well as early growth and development processes in flowers and fruitlets.
Perovic, Sanja; Seack, Jürgen; Gamulin, Vera; Müller, Werner EG; Schröder, Heinz C
2001-01-01
Background Ethylene is a widely distributed alkene product which is formed enzymatically (e.g., in plants) or by photochemical reactions (e.g., in the upper oceanic layers from dissolved organic carbon). This gaseous compound was recently found to induce in cells from the marine sponge Suberites domuncula, an increase in intracellular Ca2+ level ([Ca2+]i) and an upregulation of the expression of two genes, the potential ethylene-responsive gene, SDERR, and a Ca2+/calmodulin-dependent protein kinase. Results Here we describe for the first time, that besides sponge cells, mammalian cell lines (mouse NIH-3T3 and human HeLa and SaOS-2 cells) respond to ethylene, generated by ethephon, with an immediate and strong, transient increase in [Ca2+]i level, as demonstrated using Fura-2 imaging method. A rise of [Ca2+]i level was also found following exposure to ethylene gas of cells kept under pressure (SaOS-2 cells). The upregulation of [Ca2+]i was associated with an increase in the level of the cell cycle-associated Ki-67 antigen. In addition, we show that the effect of ethephon addition to S. domuncula cells depends on the presence of calcium in the extracellular milieu. Conclusion The results presented in this paper indicate that ethylene, previously known to act as a mediator (hormone) in plants only, deserves also attention as a potential signaling molecule in higher vertebrates. Further studies are necessary to clarify the specificity and physiological significance of the effects induced by ethylene in mammalian cells. PMID:11401726
Ormerod, J G; Nesbakken, T; Beale, S I
1990-01-01
The green sulfur bacterium Chlorobium vibrioforme contains two types of bacteriochlorophyll (Bchl). The minor pigment, Bchl a, is associated primarily with the cell membrane and its reaction centers; and the major light-harvesting antenna pigment, Bchl d, is found primarily in the chlorosomes, which are attached to the inner surface of the cell membrane. Anesthetic gases, such as N2O, ethylene, and acetylene, were found to inhibit the synthesis of Bchl d, but not of Bchl a, thus allowing the cells to grow at high light intensities with a greatly diminished content of antenna pigment. Chlorosomes were absent or sparse in inhibited cells. Porphyrins accumulated in the inhibited cells. The major one was identified as the Bchl precursor magnesium-protoporphyrin IX monomethyl ester (Mg-PPME) by comparative absorption and fluorescence spectroscopy and thin-layer chromatography of the porphyrin and its derivatives with those of authentic protoporphyrin IX. Small amounts of Mg-PPME were present in control cells, but the addition of inhibitor caused a rapid increase in the Mg-PPME concentration, accompanying the inhibition of Bchl d synthesis. Cells grown in the presence of ethephon (as a source of ethylene) and allowed to stand in dim light for long periods accumulated large amounts of PPME and other porphyrins and excreted or released porphyrins, which accumulated as a brown precipitate in the culture. Inhibition of Bchl d synthesis was relieved upon removal of the inhibitor. These results suggest that the gases act at a step in pigment biosynthesis that affects the utilization of Mg-PPME for isocyclic ring formation. Synthesis of Bchl d and Bchl a may be differentially affected by the gases because of compartmentation of their biosynthetic apparatus or because competition for precursors favors Bchl a synthesis. An ethephon-resistant mutant strain was isolated by selection for growth in dim, long-wavelength light. The mutant cells were also resistant to acetylene, but not to N2O. The ability to reversibly generate viable Chlorobium cells that lack antenna pigments may be useful in photosynthesis research. The ethephon- and acetylene-resistant strain may be useful in the study of the enzymes and genes that are involved in the biosynthetic step that the gases affect. Images FIG. 2 PMID:2307651
Characterization of physical and aerodynamic properties of walnuts
USDA-ARS?s Scientific Manuscript database
The objective of this research was to study the physical and aerodynamic properties of freshly harvested walnuts. Measurements were carried out for three walnut varieties, Tulare, Howard and Chandler cultivated in California, USA. The nuts treated with and without Ethephon were collected from mechan...
Koyama, Renata; Roberto, Sergio R.; de Souza, Reginaldo T.; Borges, Wellington F. S.; Anderson, Mauri; Waterhouse, Andrew L.; Cantu, Dario; Fidelibus, Matthew W.; Blanco-Ulate, Barbara
2018-01-01
Hybrid (Vitis vinifera ×Vitis labrusca) table grape cultivars grown in the subtropics often fail to accumulate sufficient anthocyanins to achieve good uniform berry color. Growers of V. vinifera table grapes in temperate regions generally use ethephon and, more recently, (S)-cis-abscisic acid (S-ABA) to overcome this problem. The objective of this study was to determine if S-ABA applications at different timings and concentrations have an effect on anthocyanin regulatory and biosynthetic genes, pigment accumulation, and berry color of the Selection 21 cultivar, a new V. vinifera ×V. labrusca hybrid seedless grape that presents lack of red color when grown in subtropical areas. Applications of S-ABA 400 mg/L resulted in a higher accumulation of total anthocyanins and of the individual anthocyaninsanthocyanins: delphinidin-3-glucoside, cyanidin-3-glucoside, peonidin-3-glucoside, and malvidin-3-glucoside in the berry skin and improved the color attributes of the berries. Treatment with two applications at 7 days after véraison (DAV) and 21 DAV of S-ABA 400 mg/L resulted in a higher accumulation of total anthocyanins in the skin of berries and increased the gene expression of CHI, F3H, DFR, and UFGT and of the VvMYBA1 and VvMYBA2 transcription factors in the seedless grape cultivar. PMID:29632542
Rahman, Alamgir; Kuldau, Gretchen A; Uddin, Wakar
2014-06-01
Incorporation of plant defense activators is an innovative approach to development of an integrated strategy for the management of turfgrass diseases. The effects of salicylic acid (SA), benzothiadiazole (BTH, chemical analog of SA), jasmonic acid (JA), and ethephon (ET, an ethylene-releasing compound) on development of gray leaf spot in perennial ryegrass (Lolium perenne L.) caused by Magnaporthe oryzae were evaluated. Gray leaf spot disease incidence and severity were significantly decreased when plants were treated prior to inoculation with SA, BTH, and partially by ET but not by JA. Accumulation of endogenous SA and elevated expression of pathogenesis-related (PR)-1, PR-3.1, and PR-5 genes were associated with inoculation of plants by M. oryzae. Treatment of plants with SA enhanced expression levels of PR-3.1 and PR-5 but did not affect the PR-1 level, whereas BTH treatment enhanced relative expression levels of all three PR genes. Microscopic observations of leaves inoculated with M. oryzae revealed higher frequencies of callose deposition at the penetration sites in SA- and BTH-treated plants compared with the control plants (treated with water). These results suggest that early and higher induction of these genes by systemic resistance inducers may provide perennial ryegrass with a substantial advantage to defend against infection by M. oryzae.
Wei, Junya; Liu, Debing; Liu, Guoyin; Tang, Jie; Chen, Yeyuan
2016-01-01
MADS-box transcription factor plays a crucial role in plant development, especially controlling the formation and development of floral organs. Mango ( Mangifera indica L) is an economically important fruit crop, but its molecular control of flowering is largely unknown. To better understand the molecular basis of flowering regulation in mango, we isolated and characterized the MiSOC1, a putative mango orthologs for the Arabidopsis SUPPRESSOR OF OVEREXPRESSION OF CONSTANS1/AGAMOUS-LIKE 20 (SOC1/AGL20) with homology-based cloning and RACE. The full-length cDNA (GenBank accession No.: KP404094) is 945 bp in length including a 74 bp long 5' UTR and a 189 bp long 3' UTR and the open reading frame was 733 bps, encoding 223 amino acids with molecular weight 25.6 kD. Both sequence alignment and phylogenetic analysis all indicated that deduced protein contained a conservative MADS-box and semi-conservative K domain and belonged to the SOC1/TM3 subfamily of the MADS-box family. Quantitative real-time PCR was performed to investigate the expression profiles of MiSOC1 gene in different tissues/organs including root, stem, leaves, flower bud, and flower. The result indicated MiSOC1 was widely expressed at different levels in both vegetative and reproductive tissues/organs with the highest expression level in the stems' leaves and inflorescences, low expression in roots and flowers. The expression of MiSOC1 in different flower developmental stages was different while same tissue -specific pattern among different varieties. In addition, MiSOC1 gene expression was affect by ethephon while high concentration ethephon inhibit the expression of MiSOC1. Overexpression of MiSOC1 resulted in early flowering in Arabidopsis . In conclusion, these results suggest that MiSOC1 may act as induce flower function in mango.
Wei, Junya; Liu, Debing; Liu, Guoyin; Tang, Jie; Chen, Yeyuan
2016-01-01
MADS-box transcription factor plays a crucial role in plant development, especially controlling the formation and development of floral organs. Mango (Mangifera indica L) is an economically important fruit crop, but its molecular control of flowering is largely unknown. To better understand the molecular basis of flowering regulation in mango, we isolated and characterized the MiSOC1, a putative mango orthologs for the Arabidopsis SUPPRESSOR OF OVEREXPRESSION OF CONSTANS1/AGAMOUS-LIKE 20 (SOC1/AGL20) with homology-based cloning and RACE. The full-length cDNA (GenBank accession No.: KP404094) is 945 bp in length including a 74 bp long 5′ UTR and a 189 bp long 3′ UTR and the open reading frame was 733 bps, encoding 223 amino acids with molecular weight 25.6 kD. Both sequence alignment and phylogenetic analysis all indicated that deduced protein contained a conservative MADS-box and semi-conservative K domain and belonged to the SOC1/TM3 subfamily of the MADS-box family. Quantitative real-time PCR was performed to investigate the expression profiles of MiSOC1 gene in different tissues/organs including root, stem, leaves, flower bud, and flower. The result indicated MiSOC1 was widely expressed at different levels in both vegetative and reproductive tissues/organs with the highest expression level in the stems’ leaves and inflorescences, low expression in roots and flowers. The expression of MiSOC1 in different flower developmental stages was different while same tissue –specific pattern among different varieties. In addition, MiSOC1 gene expression was affect by ethephon while high concentration ethephon inhibit the expression of MiSOC1. Overexpression of MiSOC1 resulted in early flowering in Arabidopsis. In conclusion, these results suggest that MiSOC1 may act as induce flower function in mango. PMID:27965680
Cheng, Qun; Li, Ninghui; Dong, Lidong; Zhang, Dayong; Fan, Sujie; Jiang, Liangyu; Wang, Xin; Xu, Pengfei; Zhang, Shuzhen
2015-01-01
Isoflavone reductase (IFR) is an enzyme involved in the biosynthetic pathway of isoflavonoid phytoalexin in plants. IFRs are unique to the plant kingdom and are considered to have crucial roles in plant response to various biotic and abiotic environmental stresses. Here, we report the characterization of a novel member of the soybean isoflavone reductase gene family GmIFR. Overexpression of GmIFR transgenic soybean exhibited enhanced resistance to Phytophthora sojae. Following stress treatments, GmIFR was significantly induced by P. sojae, ethephon (ET), abscisic acid (placeCityABA), salicylic acid (SA). It is located in the cytoplasm when transiently expressed in soybean protoplasts. The daidzein levels reduced greatly for the seeds of transgenic plants, while the relative content of glyceollins in transgenic plants was significantly higher than that of non-transgenic plants. Furthermore, we found that the relative expression levels of reactive oxygen species (ROS) of transgenic soybean plants were significantly lower than those of non-transgenic plants after incubation with P. sojae, suggesting an important role of GmIFR might function as an antioxidant to reduce ROS in soybean. The enzyme activity assay suggested that GmIFR has isoflavone reductase activity. PMID:26635848
Cheng, Qun; Li, Ninghui; Dong, Lidong; Zhang, Dayong; Fan, Sujie; Jiang, Liangyu; Wang, Xin; Xu, Pengfei; Zhang, Shuzhen
2015-01-01
Isoflavone reductase (IFR) is an enzyme involved in the biosynthetic pathway of isoflavonoid phytoalexin in plants. IFRs are unique to the plant kingdom and are considered to have crucial roles in plant response to various biotic and abiotic environmental stresses. Here, we report the characterization of a novel member of the soybean isoflavone reductase gene family GmIFR. Overexpression of GmIFR transgenic soybean exhibited enhanced resistance to Phytophthora sojae. Following stress treatments, GmIFR was significantly induced by P. sojae, ethephon (ET), abscisic acid (placeCityABA), salicylic acid (SA). It is located in the cytoplasm when transiently expressed in soybean protoplasts. The daidzein levels reduced greatly for the seeds of transgenic plants, while the relative content of glyceollins in transgenic plants was significantly higher than that of non-transgenic plants. Furthermore, we found that the relative expression levels of reactive oxygen species (ROS) of transgenic soybean plants were significantly lower than those of non-transgenic plants after incubation with P. sojae, suggesting an important role of GmIFR might function as an antioxidant to reduce ROS in soybean. The enzyme activity assay suggested that GmIFR has isoflavone reductase activity.
Yan, Qiang; Cui, Xiaoxia; Lin, Shuai; Gan, Shuping; Xing, Han; Dou, Daolong
2016-01-01
The cytochrome P450 monooxygenases (P450s) represent a large and important enzyme superfamily in plants. They catalyze numerous monooxygenation/hydroxylation reactions in biochemical pathways, P450s are involved in a variety of metabolic pathways and participate in the homeostasis of phytohormones. The CYP82 family genes specifically reside in dicots and are usually induced by distinct environmental stresses. However, their functions are largely unknown, especially in soybean (Glycine max L.). Here, we report the function of GmCYP82A3, a gene from soybean CYP82 family. Its expression was induced by Phytophthora sojae infection, salinity and drought stresses, and treatment with methyl jasmonate (MeJA) or ethephon (ETH). Its expression levels were consistently high in resistant cultivars. Transgenic Nicotiana benthamiana plants overexpressing GmCYP82A3 exhibited strong resistance to Botrytis cinerea and Phytophthora parasitica, and enhanced tolerance to salinity and drought stresses. Furthermore, transgenic plants were less sensitive to jasmonic acid (JA), and the enhanced resistance was accompanied with increased expression of the JA/ET signaling pathway-related genes. PMID:27588421
NASA Technical Reports Server (NTRS)
Pressman, E.; Huberman, M.; Aloni, B.; Jaffe, M. J.
1984-01-01
Mechanical perturbation (MP) applied to celery (Appium graveolens L. cv. Florida 683) leaf petioles or ethephon application to the plant did not induce thigmomorphogenesis (inhibition of elongation and increase in thickness of the petiole). However, the two treatments did cause the parenchyma breakdown which leads to pithiness or increased natural pithiness, mainly at the base of the petiole. Nevertheless, MP (but not ethephon) decreased the severity of drought-stress or GA3-induced pithiness. Although MP stimulates ethylene production, mainly at the middle part of the petiole, it seems that the protection by MP of the petiole may not be directly mediated by ethylene production. The exposure of the plant to drought stress brought about an increase in ethylene evolution. Upon reirrigating the plants, the first steps of pithiness were accompanied by a sharp decline in ethylene production. This decrease might be due to membrane disruption. The increase in ethylene production during drought stress may be one of the events which stimulate pithiness of the celery leaf petiole.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Ormerod, J.G.; Nesbakken, T.; Beale, S.I.
1990-03-01
The green sulfur bacterium Chlorobium vibrioforme contains two types of bacteriochlorophll (Bchl). The minor pigment, Bchl a, is associated primarily with the cell membrane and its reaction centers; and the major light-harvesting antenna pigment, Bchl d, is found primarily in the chlorosomes, which are attached to the inner surface of the cell membrane. Anesthetic gases, such as N{sub 2}O, ethylene, and acetylene, were found to inhibit the synthesis of Bchl d, but not of Bchl a, thus allowing the cells to grow at high light intensities with a greatly diminished content of antenna pgiment. Chlorosomes were absent or sparse inmore » inhibited cells. Porphyrins accumulated in the inhibited cells. Result suggest that the gases act at a step in pigment biosynthesis that affect the utilization of the major one was identified as the Bchl precursor magnesium-protoporphyrin IX monomethyl ester (Mg-PPME) for isocyclic ring formation. Synthesis of Bchl d and Bchl a may be differentially affected by the gases because of compartmentation of their biosynthetic apparatus or because competition for precursors favors Bchl a synthesis. An ethephon-resistant mutant strain was isolated by selection for growth in dim, long-wavelength light. The mutant cells were also resistant to acetylene, but not to N{sub 2}O. The ability to reversibly generate viable Chlorobium cells that lack antenna pigments may be useful in photosynthesis research. The ethephon-and acetylene-resistant strain may be useful in the study of the enzymes and genes that are involved in the biosynthetic step that the gases affect.« less
Hu, Yang; Han, Yong-Tao; Wei, Wei; Li, Ya-Juan; Zhang, Kai; Gao, Yu-Rong; Zhao, Feng-Li; Feng, Jia-Yue
2015-01-01
Heat shock transcription factors (Hsfs) are known to play dominant roles in plant responses to heat, as well as other abiotic or biotic stress stimuli. While the strawberry is an economically important fruit plant, little is known about the Hsf family in the strawberry. To explore the functions of strawberry Hsfs in abiotic and biotic stress responses, this study identified 17 Hsf genes (FvHsfs) in a wild diploid woodland strawberry (Fragaria vesca, 2n = 2x = 14) and isolated 14 of these genes. Phylogenetic analysis divided the strawberry FvHsfs genes into three main groups. The evolutionary and structural analyses revealed that the FvHsf family is conserved. The promoter sequences of the FvHsf genes contain upstream regulatory elements corresponding to different stress stimuli. In addition, 14 FvHsf-GFP fusion proteins showed differential subcellular localization in Arabidopsis mesophyll protoplasts. Furthermore, we examined the expression of the 17 FvHsf genes in wild diploid woodland strawberries under various conditions, including abiotic stresses (heat, cold, drought, and salt), biotic stress (powdery mildew infection), and hormone treatments (abscisic acid, ethephon, methyl jasmonate, and salicylic acid). Fifteen of the seventeen FvHsf genes exhibited distinct changes on the transcriptional level during heat treatment. Of these 15 FvHsfs, 8 FvHsfs also exhibited distinct responses to other stimuli on the transcriptional level, indicating versatile roles in the response to abiotic and biotic stresses. Taken together, the present work may provide the basis for further studies to dissect FvHsf function in response to stress stimuli. PMID:26442049
Yuk, Heung Joo; Song, Yeong Hun; Curtis-Long, Marcus J; Kim, Dae Wook; Woo, Su Gyeong; Lee, Yong Bok; Uddin, Zia; Kim, Cha Young; Park, Ki Hun
2016-10-05
Dietary isoflavones, daidzein and genistein are of huge interest in the nutraceutical field due to their practical application to postmenopause complications. This study is the first report an efficient method to prepare isoflavone rich soybean leaves (soyleaves) which is an edible food stuff in Asian countries. The preharvest treatment of ethylene highly stimulated the level of isoflavone in soyleaves. Annotation and quantification of metabolites were determined by UPLC-Q-TOF-MS and HPLC. Phenolic metabolites of soyleaves are mostly kaempferol glycosides, but not dietary isoflavones. The accumulated isoflavones by ethylene treatment were determined to be daidzin 1, genistin 2, malonyldaidzin 3 and malonylgenistin 4, which were easily hydrolyzed to daidzein and genistein by β-glucosidase. Total content of dietary isoflavones was increased up to 13854 μg/g. The most suitable condition was estimated to be 250 μg/g ethylene or 200 μg/g ethephon (ethylene donor) treatment at the R3 growth stage. The ratio of daidzein and genistein glycosides was approximately 5 to 3. The accumulated isoflavonoid biosynthesis pathway genes were identified within the transcriptome of soyleaves tissues at 1 day after treatment of ethephon. The quantitative RT-PCR analysis of these genes indicated significantly higher expression of CHS, CHI, IFS, HID, IF7GT, and IF7MaT compared to control leaves. These findings suggest that ethylene activates a set of structural genes involved in isoflavonoid biosynthesis, thereby leading to enhanced production of isoflavones in soybean plants.
Gravitropism in leafy dicot stems
NASA Technical Reports Server (NTRS)
Salisbury, F. B.
1984-01-01
In an attempt to separate plant responses to mechanical stresses from responses to gravity compensation, six treatments were automated: (1) upright stationary controls; (2) horizontal clinostat; (3) intermittent clinostat (plants upright 3.3 minutes out of every 4 minutes, horizontal and rotated once in the remaining time); (4) inversion every ten minutes (plants upside down half the time); (5) inversion and immediate return to the vertical; and (6) vertical rotation. Epinasty appeared only on clinostated and on inverted plants, both subjected to gravity compensation. The mechanics of gravitropic stem bending and the effects of a unilateral application of ethephon of gravitropic bending were also investigated.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Lee, Boo-Ja; Park, Chang-Jin; Kim, Sung-Kyu
2006-05-26
We find that salicylic acid and ethephon treatment in hot pepper increases the expression of a putative basic/leucine zipper (bZIP) transcription factor gene, CabZIP1. CabZIP1 mRNA is expressed ubiquitously in various organs. The green fluorescent protein-fused transcription factor, CabZIP1::GFP, can be specifically localized to the nucleus, an action that is consistent with the presence of a nuclear localization signal in its protein sequence. Transient overexpression of the CabZIP1 transcription factor results in an increase in PR-1 transcripts level in Nicotiana benthamiana leaves. Using chromatin immunoprecipitation, we demonstrate that CabZIP1 binds to the G-box elements in native promoter of the hotmore » pepper pathogenesis-related protein 1 (CaPR-1) gene in vivo. Taken together, our results suggest that CabZIP1 plays a role as a transcriptional regulator of the CaPR-1 gene.« less
Yang, Yuwen; Chen, Tianzi; Ling, Xitie; Ma, Zhengqiang
2018-01-01
Verticillium wilt is a soil-borne disease that can cause devastating losses in cotton production. Because there is no effective chemical means to combat the disease, the only effective way to control Verticillium wilt is through genetic improvement. Therefore, the identification of additional disease-resistance genes will benefit efforts toward the genetic improvement of cotton resistance to Verticillium wilt. Based on screening of a BAC library with a partial Ve homologous fragment and expression analysis, a V. dahliae-induced gene, Gbvdr6, was isolated and cloned from the Verticillium wilt-resistant cotton G. barbadense cultivar Hai7124. The gene was located in the gene cluster containing Gbve1 and Gbvdr5 and adjacent to the Verticillium wilt-resistance QTL hotspot. Gbvdr6 was induced by Verticillium dahliae Kleb and by the plant hormones salicylic acid (SA), methyl jasmonate (MeJA) and ethephon (ETH) but not by abscisic acid (ABA). Gbvdr6 was localized to the plasma membrane. Overexpression of Gbvdr6 in Arabidopsis and cotton enhanced resistance to V. dahliae. Moreover, the JA/ET signaling pathway-related genes PR3, PDF 1.2, ERF1 and the SA-related genes PR1 and PR2 were constitutively expressed in transgenic plants. Gbvdr6-overexpressing Arabidopsis was less sensitive than the wild-type plant to MeJA. Furthermore, the accumulation of reactive oxygen species and callose was triggered at early time points after V. dahliae infection. These results suggest that Gbvdr6 confers resistance to V. dahliae through regulation of the JA/ET and SA signaling pathways. PMID:29387078
Wei, Wei; Hu, Yang; Han, Yong-Tao; Zhang, Kai; Zhao, Feng-Li; Feng, Jia-Yue
2016-08-01
WRKY proteins comprise a large family of transcription factors that play important roles in response to biotic and abiotic stresses and in plant growth and development. To date, little is known about the WRKY gene family in strawberry. In this study, we identified 62 WRKY genes (FvWRKYs) in the wild diploid woodland strawberry (Fragaria vesca, 2n = 2x = 14) accession Heilongjiang-3. According to the phylogenetic analysis and structural features, these identified strawberry FvWRKY genes were classified into three main groups. In addition, eight FvWRKY-GFP fusion proteins showed distinct subcellular localizations in Arabidopsis mesophyll protoplasts. Furthermore, we examined the expression of the 62 FvWRKY genes in 'Heilongjiang-3' under various conditions, including biotic stress (Podosphaera aphanis), abiotic stresses (drought, salt, cold, and heat), and hormone treatments (abscisic acid, ethephon, methyl jasmonate, and salicylic acid). The expression levels of 33 FvWRKY genes were upregulated, while 12 FvWRKY genes were downregulated during powdery mildew infection. FvWRKY genes responded to drought and salt treatment to a greater extent than to temperature stress. Expression profiles derived from quantitative real-time PCR suggested that 11 FvWRKY genes responded dramatically to various stimuli at the transcriptional level, indicating versatile roles in responses to biotic and abiotic stresses. Interaction networks revealed that the crucial pathways controlled by WRKY proteins may be involved in the differential response to biotic stress. Taken together, the present work may provide the basis for future studies of the genetic modification of WRKY genes for pathogen resistance and stress tolerance in strawberry. Copyright © 2016 Elsevier Masson SAS. All rights reserved.
Involvement of Ethylene in the Latex Metabolism and Tapping Panel Dryness of Hevea brasiliensis
Putranto, Riza-Arief; Herlinawati, Eva; Rio, Maryannick; Leclercq, Julie; Piyatrakul, Piyanuch; Gohet, Eric; Sanier, Christine; Oktavia, Fetrina; Pirrello, Julien; Kuswanhadi; Montoro, Pascal
2015-01-01
Ethephon, an ethylene releaser, is used to stimulate latex production in Hevea brasiliensis. Ethylene induces many functions in latex cells including the production of reactive oxygen species (ROS). The accumulation of ROS is responsible for the coagulation of rubber particles in latex cells, resulting in the partial or complete stoppage of latex flow. This study set out to assess biochemical and histological changes as well as changes in gene expression in latex and phloem tissues from trees grown under various harvesting systems. The Tapping Panel Dryness (TPD) susceptibility of Hevea clones was found to be related to some biochemical parameters, such as low sucrose and high inorganic phosphorus contents. A high tapping frequency and ethephon stimulation induced early TPD occurrence in a high latex metabolism clone and late occurrence in a low latex metabolism clone. TPD-affected trees had smaller number of laticifer vessels compared to healthy trees, suggesting a modification of cambial activity. The differential transcript abundance was observed for twenty-seven candidate genes related to TPD occurrence in latex and phloem tissues for ROS-scavenging, ethylene biosynthesis and signalling genes. The predicted function for some Ethylene Response Factor genes suggested that these candidate genes should play an important role in regulating susceptibility to TPD. PMID:26247941
Involvement of Ethylene in the Latex Metabolism and Tapping Panel Dryness of Hevea brasiliensis.
Putranto, Riza-Arief; Herlinawati, Eva; Rio, Maryannick; Leclercq, Julie; Piyatrakul, Piyanuch; Gohet, Eric; Sanier, Christine; Oktavia, Fetrina; Pirrello, Julien; Kuswanhadi; Montoro, Pascal
2015-08-04
Ethephon, an ethylene releaser, is used to stimulate latex production in Hevea brasiliensis. Ethylene induces many functions in latex cells including the production of reactive oxygen species (ROS). The accumulation of ROS is responsible for the coagulation of rubber particles in latex cells, resulting in the partial or complete stoppage of latex flow. This study set out to assess biochemical and histological changes as well as changes in gene expression in latex and phloem tissues from trees grown under various harvesting systems. The Tapping Panel Dryness (TPD) susceptibility of Hevea clones was found to be related to some biochemical parameters, such as low sucrose and high inorganic phosphorus contents. A high tapping frequency and ethephon stimulation induced early TPD occurrence in a high latex metabolism clone and late occurrence in a low latex metabolism clone. TPD-affected trees had smaller number of laticifer vessels compared to healthy trees, suggesting a modification of cambial activity. The differential transcript abundance was observed for twenty-seven candidate genes related to TPD occurrence in latex and phloem tissues for ROS-scavenging, ethylene biosynthesis and signalling genes. The predicted function for some Ethylene Response Factor genes suggested that these candidate genes should play an important role in regulating susceptibility to TPD.
A plant EPF-type zinc-finger protein, CaPIF1, involved in defence against pathogens.
Oh, Sang-Keun; Park, Jeong Mee; Joung, Young Hee; Lee, Sanghyeob; Chung, Eunsook; Kim, Soo-Yong; Yu, Seung Hun; Choi, Doil
2005-05-01
SUMMARY To understand better the defence responses of plants to pathogen attack, we challenged hot pepper plants with bacterial pathogens and identified transcription factor-encoding genes whose expression patterns were altered during the subsequent hypersensitive response. One of these genes, CaPIF1 (Capsicum annuum Pathogen-Induced Factor 1), was characterized further. This gene encodes a plant-specific EPF-type protein that contains two Cys(2)/His(2) zinc fingers. CaPIF1 expression was rapidly and specifically induced when pepper plants were challenged with bacterial pathogens to which they are resistant. In contrast, challenge with a pathogen to which the plants are susceptible only generated weak CaPIF1 expression. CaPIF1 expression was also strongly induced in pepper leaves by the exogenous application of ethephon, an ethylene-releasing compound, and salicylic acid, whereas methyl jasmonate had only moderate effects. CaPIF1 localized to the nuclei of onion epidermis when expressed as a CaPIF1-smGFP fusion protein. Transgenic tobacco plants over-expressing CaPIF1 driven by the CaMV 35S promoter showed increased resistance to challenge with a tobacco-specific pathogen or non-host bacterial pathogens. These plants also showed constitutive up-regulation of multiple defence-related genes. Moreover, virus-induced silencing of the CaPIF1 orthologue in Nicotiana benthamiana enhanced susceptibility to the same host or non-host bacterial pathogens. These observations provide evidence that an EPF-type Cys(2)/His(2) zinc-finger protein plays a crucial role in the activation of the pathogen defence response in plants.
Wei, Wei; Chai, Zhuangzhuang; Xie, Yinge; Gao, Kuan; Cui, Mengyuan; Jiang, Ying
2017-01-01
Mitogen-activated protein kinases (MAPKs) play essential roles in mediating biotic and abiotic stress responses in plants. However, the MAPK gene family in strawberry has not been systematically characterized. Here, we performed a genome-wide survey and identified 12 MAPK genes in the Fragaria vesca genome. Protein domain analysis indicated that all FvMAPKs have typical protein kinase domains. Sequence alignments and phylogenetic analysis classified the FvMAPK genes into four different groups. Conserved motif and exon-intron organization supported the evolutionary relationships inferred from the phylogenetic analysis. Analysis of the stress-related cis-regulatory element in the promoters and subcellular localization predictions of FvMAPKs were also performed. Gene transcript profile analysis showed that the majority of the FvMAPK genes were ubiquitously transcribed in strawberry leaves after Podosphaera aphanis inoculation and after treatment with cold, heat, drought, salt and the exogenous hormones abscisic acid, ethephon, methyl jasmonate, and salicylic acid. RT-qPCR showed that six selected FvMAPK genes comprehensively responded to various stimuli. Additionally, interaction networks revealed that the crucial signaling transduction controlled by FvMAPKs may be involved in the biotic and abiotic stress responses. Our results may provide useful information for future research on the function of the MAPK gene family and the genetic improvement of strawberry resistance to environmental stresses. PMID:28562633
Yi, S Y; Hwang, B K
1998-10-31
Differential display techniques were used to isolate cDNA clones corresponding to genes which were expressed in soybean hypocotyls by Phytophthora sojae f.sp. glycines infection. With a partial cDNA clone C20CI4 from the differential display PCR as a probe, a new basic peroxidase cDNA clone, designated GMIPER1, was isolated from a cDNA library of soybean hypocotyls infected with P. sojae f.sp. glycines. Sequence analysis revealed that the peroxidase clone encodes a mature protein of 35,813 Da with a putative signal peptide of 27 amino acids in its N-terminus. The amino acid sequence of the soybean peroxidase GMIPER1 is between 54-75% identical to other plant peroxidases including a soybean seed coat peroxidase. Southern blot analysis indicated that multiple copies of sequences related to GMIPER1 exist in the soybean genome. The mRNAs corresponding to the GMIPER1 cDNA accumulated predominantly in the soybean hypocotyls infected with the incompatible race of P. sojae f.sp. glycines, but were expressed at low levels in the compatible interaction. Soybean GMIPER1 mRNAs were not expressed in hypocotyls, leaves, stems, and roots of soybean seedlings. However, treatments with ethephon, salicylic acid or methyl jasmonate induced the accumulation of the GMIPER1 mRNAs in the different organs of soybean. These results suggest that the GMIPER1 gene encoding a putative pathogen-induced peroxidase may play an important role in induced resistance of soybean to P. sojae f.sp. glycines and in response to various external stresses.
Effects of pre-harvest chemical application on rice desiccation and seed quality*
HE, Yong-qi; CHENG, Jin-ping; LIU, Liang-feng; LI, Xiao-dan; YANG, Bin; ZHANG, Hong-sheng; WANG, Zhou-fei
2015-01-01
Pre-harvest desiccation may increase the efficiency of seed production. Field studies were conducted to determine the effects of diquat, paraquat, and ethephon applications on grain moisture, grain weight, and seed germination of hybrid rice Yanliangyou 88 (Oryza sativa ssp. indica) and conventional rice Wuyunjing 7 (Oryza sativa ssp. japonica). In 2013, we tested 12 treatments applied at four weeks (Yanliangyou 88) and six weeks (Wuyunjing 7) after heading. Results showed that reductions in moisture content were significant two and four days after chemical application. Chemical applications had no adverse effects on 1000-grain weight, germination percentage, or germination index, but there were negative effects on the percentage of normal seedlings. Desiccation effects increased with increase in the period after application, while the effect of ethephon combined with diquat or paraquat on desiccation was limited compared with that of diquat or paraquat alone in a short period after application. In 2013, chemical applications reduced the moisture content by from 0.5% to 6.4%, the germination percentage by from 0% to 3.3%, and the percentage of normal seedlings by from 13.3% to 100.0%. Among the treatments, diquat applied at 120 g/ha resulted in effective desiccation with fewer negative effects on grain weight and seed germination in 2013 and 2014. Therefore, diquat may have potential as a pre-harvest chemical desiccation treatment for rice. These results may provide a basis for developing and implementing protocols for large scale field trials. PMID:26465129
Effects of pre-harvest chemical application on rice desiccation and seed quality.
He, Yong-qi; Cheng, Jin-ping; Liu, Liang-feng; Li, Xiao-dan; Yang, Bin; Zhang, Hong-sheng; Wang, Zhou-fei
2015-10-01
Pre-harvest desiccation may increase the efficiency of seed production. Field studies were conducted to determine the effects of diquat, paraquat, and ethephon applications on grain moisture, grain weight, and seed germination of hybrid rice Yanliangyou 88 (Oryza sativa ssp. indica) and conventional rice Wuyunjing 7 (Oryza sativa ssp. japonica). In 2013, we tested 12 treatments applied at four weeks (Yanliangyou 88) and six weeks (Wuyunjing 7) after heading. Results showed that reductions in moisture content were significant two and four days after chemical application. Chemical applications had no adverse effects on 1000-grain weight, germination percentage, or germination index, but there were negative effects on the percentage of normal seedlings. Desiccation effects increased with increase in the period after application, while the effect of ethephon combined with diquat or paraquat on desiccation was limited compared with that of diquat or paraquat alone in a short period after application. In 2013, chemical applications reduced the moisture content by from 0.5% to 6.4%, the germination percentage by from 0% to 3.3%, and the percentage of normal seedlings by from 13.3% to 100.0%. Among the treatments, diquat applied at 120 g/ha resulted in effective desiccation with fewer negative effects on grain weight and seed germination in 2013 and 2014. Therefore, diquat may have potential as a pre-harvest chemical desiccation treatment for rice. These results may provide a basis for developing and implementing protocols for large scale field trials.
Hu, Lan-Ying; Chen, Xiao-Yan; Li, Yan-Hong; Yang, Ying; Yang, Feng
2017-01-01
Accumulating evidence shows that hydrogen sulfide (H2S) acts as a multifunctional signaling molecule in plants, whereas the interaction between H2S and ethylene is still unclear. In the present study we investigated the role of H2S in ethylene-promoted banana ripening and senescence by the application of ethylene released from 1.0 g·L−1 ethephon solution or H2S with 1 mM sodium hydrosulfide (NaHS) as the donor or in combination. Fumigation with ethylene was found to accelerate banana ripening and H2S treatment effectively alleviated ethylene-induced banana peel yellowing and fruit softening in parallel with decreased activity of polygalacturonase (PG). Ethylene+H2S treatment also delayed the decreases in chlorophyll and total phenolics, and increased the accumulation of flavonoid, whereas decreased the contents of carotenoid, soluble protein in banana peel and reducing sugar in pulp compared with ethylene treatment alone. Besides, ethylene+H2S treatment suppressed the accumulation of superoxide radicals (·O2−), hydrogen peroxide (H2O2) and malondialdehyde (MDA) which accumulated highly in ethylene-treated banana peels. Furthermore H2S enhanced total antioxidant capacity in ethylene-treated banana peels with the 2,2’-azobis(3-ethylbenz-thiazoline-6-sulfonic acid (ABTS) assay. The result of quantitative real-time PCR showed that the combined treatment of ethylene with H2S down-regulated the expression of ethylene synthesis genes MaACS1, MaACS2 and MaACO1 and pectate lyase MaPL compared with ethylene treatment, while the expression of ethylene receptor genes MaETR, MaERS1 and MaERS2 was enhanced in combination treatment compared with ethylene alone. In all, it can be concluded that H2S alleviates banana fruit ripening and senescence by antagonizing the effect of ethylene through reduction of oxidative stress and inhibition of ethylene signaling pathway. PMID:28662156
Ge, Yun; Hu, Kang-Di; Wang, Sha-Sha; Hu, Lan-Ying; Chen, Xiao-Yan; Li, Yan-Hong; Yang, Ying; Yang, Feng; Zhang, Hua
2017-01-01
Accumulating evidence shows that hydrogen sulfide (H2S) acts as a multifunctional signaling molecule in plants, whereas the interaction between H2S and ethylene is still unclear. In the present study we investigated the role of H2S in ethylene-promoted banana ripening and senescence by the application of ethylene released from 1.0 g·L-1 ethephon solution or H2S with 1 mM sodium hydrosulfide (NaHS) as the donor or in combination. Fumigation with ethylene was found to accelerate banana ripening and H2S treatment effectively alleviated ethylene-induced banana peel yellowing and fruit softening in parallel with decreased activity of polygalacturonase (PG). Ethylene+H2S treatment also delayed the decreases in chlorophyll and total phenolics, and increased the accumulation of flavonoid, whereas decreased the contents of carotenoid, soluble protein in banana peel and reducing sugar in pulp compared with ethylene treatment alone. Besides, ethylene+H2S treatment suppressed the accumulation of superoxide radicals (·O2-), hydrogen peroxide (H2O2) and malondialdehyde (MDA) which accumulated highly in ethylene-treated banana peels. Furthermore H2S enhanced total antioxidant capacity in ethylene-treated banana peels with the 2,2'-azobis(3-ethylbenz-thiazoline-6-sulfonic acid (ABTS) assay. The result of quantitative real-time PCR showed that the combined treatment of ethylene with H2S down-regulated the expression of ethylene synthesis genes MaACS1, MaACS2 and MaACO1 and pectate lyase MaPL compared with ethylene treatment, while the expression of ethylene receptor genes MaETR, MaERS1 and MaERS2 was enhanced in combination treatment compared with ethylene alone. In all, it can be concluded that H2S alleviates banana fruit ripening and senescence by antagonizing the effect of ethylene through reduction of oxidative stress and inhibition of ethylene signaling pathway.
Grzesik, Mieczysław; Górnik, Krzysztof; Janas, Regina; Lewandowki, Mariusz; Romanowska-Duda, Zdzislawa; Duijn, Bert van
2017-12-01
The aim of the study was to improve the effect of stratification of apple "Ligol" seeds by application of selected compounds, phytohormones, and physical methods For this purpose the seeds were stratified at 3°C in distilled water or in the presence of potassium nitrate (KNO 3 ), ethephon (ET), carbon monoxide (CO), hydrogen peroxide (H 2 O 2 ), a mixture of KNO 3 , ET, CO, H 2 O 2 , gibberellins (GA 3 ), 6-benzylaminopurine (BAP), jasmonic acid (JA), salicylic acid (SA) and a mixture of SA, GA 3 , BAP, JA, nitric oxide (NO), hydrogen chloride (HCL). Arranged protocols included various durations and combinations of selected compounds and phytohormones as well as laser and red light, heat shock - 2h heat shock (45°C) and Pulsed Radio Frequency (PRF) were investigated by germination tests and the activity of selected enzymes, gas exchange and index of chlorophyll in leaves. The obtained results showed the possibility to shorten more effectively the time of the apple 'Ligol' dormancy removal by treatments of the stratified seeds at 3°C with different biological and physical methods Selected compounds and phytohormones acted collectively as a regulatory complex controlling the course of release from dormancy. Physical methods (PRF and heat shock) additionally contributed to dormancy breakage. Duration of phytohormones or compounds impacts during stratification should be prolonged to minimum 7days to assure more balanced conditions of the regulatory complex for the acceleration of dormancy a removal. The most beneficial results were obtained after seed stratification for 7days on filter paper moistened in KNO 3 +Etephon+CO+H 2 O 2 at 3°C, and then on filter paper moistened in phytohormones (GA 3 +BAP+JA) till the end of seed germination (3°C). The application of this protocol could be a very useful tool in a shortening the apple breeding cycle since the period of removing dormancy was reduced by 38days in comparison to stratified in water. PRF has also the additive role in breaking dormancy of apple 'Ligol' seed. Positive effects of compounds and phytohormones applied during stratification remarkably accelerated the growth of developed from them seedlings. Further research is needed to optimize stratification methods with appropriate contents and concentrations of compounds and phytohormones combined with PRF exposure. Copyright © 2017 Elsevier GmbH. All rights reserved.
Salleh, Faezah Mohd; Mariotti, Lorenzo; Spadafora, Natasha D; Price, Anna M; Picciarelli, Piero; Wagstaff, Carol; Lombardi, Lara; Rogers, Hilary
2016-04-02
In many species floral senescence is coordinated by ethylene. Endogenous levels rise, and exogenous application accelerates senescence. Furthermore, floral senescence is often associated with increased reactive oxygen species, and is delayed by exogenously applied cytokinin. However, how these processes are linked remains largely unresolved. Erysimum linifolium (wallflower) provides an excellent model for understanding these interactions due to its easily staged flowers and close taxonomic relationship to Arabidopsis. This has facilitated microarray analysis of gene expression during petal senescence and provided gene markers for following the effects of treatments on different regulatory pathways. In detached Erysimum linifolium (wallflower) flowers ethylene production peaks in open flowers. Furthermore senescence is delayed by treatments with the ethylene signalling inhibitor silver thiosulphate, and accelerated with ethylene released by 2-chloroethylphosphonic acid. Both treatments with exogenous cytokinin, or 6-methyl purine (which is an inhibitor of cytokinin oxidase), delay petal senescence. However, treatment with cytokinin also increases ethylene biosynthesis. Despite the similar effects on senescence, transcript abundance of gene markers is affected differentially by the treatments. A significant rise in transcript abundance of WLS73 (a putative aminocyclopropanecarboxylate oxidase) was abolished by cytokinin or 6-methyl purine treatments. In contrast, WFSAG12 transcript (a senescence marker) continued to accumulate significantly, albeit at a reduced rate. Silver thiosulphate suppressed the increase in transcript abundance both of WFSAG12 and WLS73. Activity of reactive oxygen species scavenging enzymes changed during senescence. Treatments that increased cytokinin levels, or inhibited ethylene action, reduced accumulation of hydrogen peroxide. Furthermore, although auxin levels rose with senescence, treatments that delayed early senescence did not affect transcript abundance of WPS46, an auxin-induced gene. A model for the interaction between cytokinins, ethylene, reactive oxygen species and auxin in the regulation of floral senescence in wallflowers is proposed. The combined increase in ethylene and reduction in cytokinin triggers the initiation of senescence and these two plant growth regulators directly or indirectly result in increased reactive oxygen species levels. A fall in conjugated auxin and/or the total auxin pool eventually triggers abscission.
Genomic Organization, Phylogenetic and Expression Analysis of the B-BOX Gene Family in Tomato
Chu, Zhuannan; Wang, Xin; Li, Ying; Yu, Huiyang; Li, Jinhua; Lu, Yongen; Li, Hanxia; Ouyang, Bo
2016-01-01
The B-BOX (BBX) proteins encode a class of zinc-finger transcription factors possessing one or two B-BOX domains and in some cases an additional CCT (CO, CO-like and TOC1) motif, which play important roles in regulating plant growth, development and stress response. Nevertheless, no systematic study of BBX genes has undertaken in tomato (Solanum lycopersicum). Here we present the results of a genome-wide analysis of the 29 BBX genes in this important vegetable species. Their structures, conserved domains, phylogenetic relationships, subcellular localizations, and promoter cis-regulatory elements were analyzed; their tissue expression profiles and expression patterns under various hormones and stress treatments were also investigated in detail. Tomato BBX genes can be divided into five subfamilies, and twelve of them were found to be segmentally duplicated. Real-time quantitative PCR analysis showed that most BBX genes exhibited different temporal and spatial expression patterns. The expression of most BBX genes can be induced by drought, polyethylene glycol-6000 or heat stress. Some BBX genes were induced strongly by phytohormones such as abscisic acid, gibberellic acid, or ethephon. The majority of tomato BBX proteins was predicted to be located in nuclei, and the transient expression assay using Arabidopsis mesophyll protoplasts demonstrated that all the seven BBX members tested (SlBBX5, 7, 15, 17, 20, 22, and 24) were localized in nucleus. Our analysis of tomato BBX genes on the genome scale would provide valuable information for future functional characterization of specific genes in this family. PMID:27807440
Yu, Yan; Jin, Chongwei; Sun, Chengliang; Wang, Jinghong; Ye, Yiquan; Zhou, Weiwei; Lu, Lingli; Lin, Xianyong
2016-01-08
Inhibition of root elongation is one of the most distinct symptoms of aluminium (Al) toxicity. Although putrescine (Put) has been identified as an important signaling molecule involved in Al tolerance, it is yet unknown how Put mitigates Al-induced root inhibition. Here, the possible mechanism was investigated by using two wheat genotypes differing in Al resistance: Al-tolerant Xi Aimai-1 and Al-sensitive Yangmai-5. Aluminium caused more root inhibition in Yangmai-5 and increased ethylene production at the root apices compared to Xi Aimai-1, whereas the effects were significantly reversed by ethylene biosynthesis inhibitors. The simultaneous exposure of wheat seedlings to Al and ethylene donor, ethephon, or ethylene biosynthesis precursor, 1-aminocyclopropane-1-carboxylic acid (ACC), increased ethylene production and aggravated root inhibition, which was more pronounced in Xi Aimai-1. In contrast, Put treatment decreased ethylene production and alleviated Al-induced root inhibition in both genotypes, and the effects were more conspicuous in Yangmai-5. Furthermore, our results indicated that Al-induced ethylene production was mediated by ACC synthase (ACS) and ACC oxidase, and that Put decreased ethylene production by inhibiting ACS. Altogether, these findings indicate that ethylene is involved in Al-induced root inhibition and this process could be alleviated by Put through inhibiting ACS activity.
Cai, Hanyang; Yang, Sheng; Yan, Yan; Xiao, Zhuoli; Cheng, Junbin; Wu, Ji; Qiu, Ailian; Lai, Yan; Mou, Shaoliang; Guan, Deyi; Huang, Ronghua; He, Shuilin
2015-06-01
High temperature (HT), high humidity (HH), and pathogen infection often co-occur and negatively affect plant growth. However, these stress factors and plant responses are generally studied in isolation. The mechanisms of synergistic responses to combined stresses are poorly understood. We isolated the subgroup IIb WRKY family member CaWRKY6 from Capsicum annuum and performed quantitative real-time PCR analysis. CaWRKY6 expression was upregulated by individual or simultaneous treatment with HT, HH, combined HT and HH (HTHH), and Ralstonia solanacearum inoculation, and responded to exogenous application of jasmonic acid (JA), ethephon, and abscisic acid (ABA). Virus-induced gene silencing of CaWRKY6 enhanced pepper plant susceptibility to R. solanacearum and HTHH, and downregulated the hypersensitive response (HR), JA-, ethylene (ET)-, and ABA-induced marker gene expression, and thermotolerance-associated expression of CaHSP24, ER-small CaSHP, and Chl-small CaHSP. CaWRKY6 overexpression in pepper attenuated the HTHH-induced suppression of resistance to R. solanacearum infection. CaWRKY6 bound to and activated the CaWRKY40 promoter in planta, which is a pepper WRKY that regulates heat-stress tolerance and R. solanacearum resistance. CaWRKY40 silencing significantly blocked HR-induced cell death and reduced transcriptional expression of CaWRKY40. These data suggest that CaWRKY6 is a positive regulator of R. solanacearum resistance and heat-stress tolerance, which occurs in part by activating CaWRKY40. © The Author 2015. Published by Oxford University Press on behalf of the Society for Experimental Biology. All rights reserved. For permissions, please email: journals.permissions@oup.com.
Meng, Xiangxiang; Song, Qiling; Ye, Jiabao; Wang, Lanlan; Xu, Feng
2017-10-12
3-Hydroxy-3-methylglutaryl-CoA synthase (HMGS) is one of the rate-limiting enzymes in the mevalonate pathway as it catalyzes the condensation of acetoacetyl-CoA to form 3-hydroxy-3-methylglutaryl-CoA. In this study, A HMGS gene (designated as GbHMGS1 ) was cloned from Ginkgo biloba for the first time. GbHMGS1 contained a 1422-bp open-reading frame encoding 474 amino acids. Comparative and bioinformatics analysis revealed that GbHMGS1 was extensively homologous to HMGSs from other plant species. Phylogenetic analysis indicated that the GbHMGS1 belonged to the plant HMGS superfamily, sharing a common evolutionary ancestor with other HMGSs, and had a further relationship with other gymnosperm species. The yeast complement assay of GbHMGS1 in HMGS -deficient Saccharomyces cerevisiae strain YSC6274 demonstrated that GbHMGS1 gene encodes a functional HMGS enzyme. The recombinant protein of GbHMGS1 was successfully expressed in E. coli . The in vitro enzyme activity assay showed that the k cat and K m values of GbHMGS1 were 195.4 min -1 and 689 μM, respectively. GbHMGS1 was constitutively expressed in all tested tissues, including the roots, stems, leaves, female flowers, male flowers and fruits. The transcript accumulation for GbHMGS1 was highest in the leaves. Expression profiling analyses revealed that GbHMGS1 expression was induced by abiotic stresses (ultraviolet B and cold) and hormone treatments (salicylic acid, methyl jasmonate, and ethephon) in G. biloba , indicating that GbHMGS1 gene was involved in the response to environmental stresses and plant hormones.
Lee, Yun Sun; Ju, Hyun Kyoung; Kim, Yeon Jeong; Lim, Tae-Gyu; Uddin, Md Romij; Kim, Yeon Bok; Baek, Jin Hong; Kwon, Sung Won; Lee, Ki Won; Seo, Hak Soo; Park, Sang Un; Yang, Tae-Jin
2013-01-01
Aloe vera (Asphodeloideae) is a medicinal plant in which useful secondary metabolites are plentiful. Among the representative secondary metabolites of Aloe vera are the anthraquinones including aloe emodin and chrysophanol, which are tricyclic aromatic quinones synthesized via a plant-specific type III polyketide biosynthesis pathway. However, it is not yet clear which cellular responses can induce the pathway, leading to production of tricyclic aromatic quinones. In this study, we examined the effect of endogenous elicitors on the type III polyketide biosynthesis pathway and identified the metabolic changes induced in elicitor-treated Aloe vera adventitious roots. Salicylic acid, methyl jasmonate, and ethephon were used to treat Aloe vera adventitious roots cultured on MS liquid media with 0.3 mg/L IBA for 35 days. Aloe emodin and chrysophanol were remarkably increased by the SA treatment, more than 10-11 and 5-13 fold as compared with untreated control, respectively. Ultra-performance liquid chromatography-electrospray ionization mass spectrometry analysis identified a total of 37 SA-induced compounds, including aloe emodin and chrysophanol, and 3 of the compounds were tentatively identified as tricyclic aromatic quinones. Transcript accumulation analysis of polyketide synthase genes and gas chromatography mass spectrometry showed that these secondary metabolic changes resulted from increased expression of octaketide synthase genes and decreases in malonyl-CoA, which is the precursor for the tricyclic aromatic quinone biosynthesis pathway. In addition, anti-inflammatory activity was enhanced in extracts of SA-treated adventitious roots. Our results suggest that SA has an important role in activation of the plant specific-type III polyketide biosynthetic pathway, and therefore that the efficacy of Aloe vera as medicinal agent can be improved through SA treatment.
Lee, Yun Sun; Ju, Hyun Kyoung; Kim, Yeon Jeong; Lim, Tae-Gyu; Uddin, Md Romij; Kim, Yeon Bok; Baek, Jin Hong; Kwon, Sung Won; Lee, Ki Won; Seo, Hak Soo; Park, Sang Un; Yang, Tae-Jin
2013-01-01
Aloe vera (Asphodeloideae) is a medicinal plant in which useful secondary metabolites are plentiful. Among the representative secondary metabolites of Aloe vera are the anthraquinones including aloe emodin and chrysophanol, which are tricyclic aromatic quinones synthesized via a plant-specific type III polyketide biosynthesis pathway. However, it is not yet clear which cellular responses can induce the pathway, leading to production of tricyclic aromatic quinones. In this study, we examined the effect of endogenous elicitors on the type III polyketide biosynthesis pathway and identified the metabolic changes induced in elicitor-treated Aloe vera adventitious roots. Salicylic acid, methyl jasmonate, and ethephon were used to treat Aloe vera adventitious roots cultured on MS liquid media with 0.3 mg/L IBA for 35 days. Aloe emodin and chrysophanol were remarkably increased by the SA treatment, more than 10–11 and 5–13 fold as compared with untreated control, respectively. Ultra-performance liquid chromatography-electrospray ionization mass spectrometry analysis identified a total of 37 SA-induced compounds, including aloe emodin and chrysophanol, and 3 of the compounds were tentatively identified as tricyclic aromatic quinones. Transcript accumulation analysis of polyketide synthase genes and gas chromatography mass spectrometry showed that these secondary metabolic changes resulted from increased expression of octaketide synthase genes and decreases in malonyl-CoA, which is the precursor for the tricyclic aromatic quinone biosynthesis pathway. In addition, anti-inflammatory activity was enhanced in extracts of SA-treated adventitious roots. Our results suggest that SA has an important role in activation of the plant specific-type III polyketide biosynthetic pathway, and therefore that the efficacy of Aloe vera as medicinal agent can be improved through SA treatment. PMID:24358188
Liu, Zhiqin; Shi, Lanping; Liu, Yanyan; Tang, Qian; Shen, Lei; Yang, Sheng; Cai, Jinsen; Yu, Huanxin; Wang, Rongzhang; Wen, Jiayu; Lin, Youquan; Hu, Jiong; Liu, Cailing; Zhang, Yangwen; Mou, Shaoliang; He, Shuilin
2015-01-01
The tripartite mitogen-activated protein kinase (MAPK) signaling cascades have been implicated in plant growth, development, and environment adaptation, but a comprehensive understanding of MAPK signaling at genome-wide level is limited in Capsicum annuum. Herein, genome-wide identification and transcriptional expression analysis of MAPK and MAPK kinase (MAPKK) were performed in pepper. A total of 19 pepper MAPK (CaMAPKs) genes and five MAPKK (CaMAPKKs) genes were identified. Phylogenetic analysis indicated that CaMAPKs and CaMAPKKs could be classified into four groups and each group contains similar exon-intron structures. However, significant divergences were also found. Notably, five members of the pepper MAPKK family were much less conserved than those found in Arabidopsis, and 9 Arabidopsis MAPKs did not have orthologs in pepper. Additionally, 7 MAPKs in Arabidopsis had either two or three orthologs in the pepper genome, and six pepper MAPKs and one MAPKK differing in sequence were found in three pepper varieties. Quantitative real-time RT-PCR analysis showed that the majority of MAPK and MAPKK genes were ubiquitously expressed and transcriptionally modified in pepper leaves after treatments with heat, salt, and Ralstonia solanacearum inoculation as well as exogenously applied salicylic acid, methyl jasmonate, ethephon, and abscisic acid. The MAPKK-MAPK interactome was tested by yeast two-hybrid assay, the results showed that one MAPKK might interact with multiple MAPKs, one MAPK might also interact with more than one MAPKKs, constituting MAPK signaling networks which may collaborate in transmitting upstream signals into appropriate downstream cellular responses and processes. These results will facilitate future functional characterization of MAPK cascades in pepper. PMID:26442088
Yin, Jing; Li, Xin; Zhan, Yaguang; Li, Ying; Qu, Ziyue; Sun, Lu; Wang, Siyao; Yang, Jie; Xiao, Jialei
2017-11-21
Birch (Betula platyphylla Suk.) contains triterpenoids with anti-HIV and anti-tumor pharmacological activities. However, the natural abundance of these triterpenoids is low, and their chemical synthesis is costly. Transcription factors have the ability to regulate the metabolite pathways of triterpenoids via multi-gene control, thereby improving metabolite yield. Thus, transcription factors have the potential to facilitate the production of birch triterpenoids. Plant bHLH (basic helix-loop-helix) transcription factors play important roles in stress response and secondary metabolism. In this study, we cloned two genes, BpMYC4 and BpbHLH9, that encode bHLH transcription factors in Betula platyphylla Suk. The open reading frame (ORF) of BpMYC4 was 1452 bp and encoded 483 amino acids, while the ORF of BpbHLH9 was 1140 bp and encoded 379 amino acids. The proteins of BpMYC4 and BpbHLH9 were localized in the cell membrane and nucleus. The tissue-specific expression patterns revealed that BpMYC4 expression in leaves was similar to that in the stem and higher than in the roots. The expression of BpbHLH9 was higher in the leaves than in the root and stem. The expressions of BpMYC4 and BpbHLH9 increased after treatment with abscisic acid, methyl jasmonate, and gibberellin and decreased after treatment with ethephon. The promoters of BpMYC4 and BpbHLH9 were isolated using a genome walking approach, and 900-bp and 1064-bp promoter sequences were obtained for BpMYC4 and BpbHLH9, respectively. The ORF of BpbHLH9 was ligated into yeast expression plasmid pYES3 and introduced into INVScl and INVScl1-pYES2-SS yeast strains. The squalene and total triterpenoid contents in the different INVScl1 transformants decreased in the following order INVScl1-pYES-SS-bHLH9 > INVScl1-pYES3-bHLH9 > INVScl1-pYES2- BpSS > INVScl-pYES2. In BpbHLH9 transgenic birch, the relative expression of the genes that encodes for enzymes critical for triterpenoid synthesis showed a different level of up-regulation compair with wild birch(control), and the contents of betulinic acid, oleanolic acid and betulin in bHLH9-8 transgenic birch were increased by 11.35%, 88.34% and 23.02% compared to in wild birch, respectively. Our results showed that the modulation of BpbHLH9 by different hormones affected triterpenoid synthesis and triterpenoid contents. This is the first report of the cloning of BpbHLH9, and the findings are important for understanding the regulatory role of BpbHLH9 in the synthesis of birch triterpenoids.
Wang, Zemin; Zhang, Ning; Zhou, Xiangyan; Fan, Qiang; Si, Huaijun; Wang, Di
2015-04-01
Ethylene response factor (ERF) is a major subfamily of the AP2/ERF family and plays significant roles in the regulation of abiotic- and biotic-stress responses. ERF proteins can interact with the GCC-box cis-element and then initiate a transcriptional cascade activating downstream ethylene response and enhancing plant stress tolerance. In this research, we cloned five StERF genes from potato (Solanum tuberosum L.). The expressional analysis of StERF genes revealed that they showed tissue- or organ-specific expression patterns and the expression levels in leaf, stem, root, flower, and tuber were different. The assays of quantitative real-time polymerase chain reaction (qRT-PCR) and the reverse transcription-PCR (RT-PCR) showed that the expression of five StERF genes was regulated by ethephon, methyl jasmonate (MeJA), salt and drought stress. The result from the yeast one-hybrid experiment showed that five StERFs had trans-activation activity and could specifically bind to the GCC-box cis-elements. The StERFs responded to abiotic factors and hormones suggested that they possibly had diverse roles in stress and hormone regulation of potato. Copyright © 2015 Académie des sciences. Published by Elsevier SAS. All rights reserved.
Dang, Fengfeng; Wang, Yuna; She, Jianju; Lei, Yufen; Liu, Zhiqin; Eulgem, Thomas; Lai, Yan; Lin, Jing; Yu, Lu; Lei, Dan; Guan, Deyi; Li, Xia; Yuan, Qian; He, Shuilin
2014-03-01
WRKY proteins are encoded by a large gene family and are linked to many biological processes across a range of plant species. The functions and underlying mechanisms of WRKY proteins have been investigated primarily in model plants such as Arabidopsis and rice. The roles of these transcription factors in non-model plants, including pepper and other Solanaceae, are poorly understood. Here, we characterize the expression and function of a subgroup IIe WRKY protein from pepper (Capsicum annuum), denoted as CaWRKY27. The protein localized to nuclei and activated the transcription of a reporter GUS gene construct driven by the 35S promoter that contained two copies of the W-box in its proximal upstream region. Inoculation of pepper cultivars with Ralstonia solanacearum induced the expression of CaWRKY27 transcript in 76a, a bacterial wilt-resistant pepper cultivar, whereas it downregulated the expression of CaWRKY27 transcript in Gui-1-3, a bacterial wilt-susceptible pepper cultivar. CaWRKY27 transcript levels were also increased by treatments with salicylic acid (SA), methyl jasmonate (MeJA) and ethephon (ETH). Transgenic tobacco plants overexpressing CaWRKY27 exhibited resistance to R. solanacearum infection compared to that of wild-type plants. This resistance was coupled with increased transcript levels in a number of marker genes, including hypersensitive response genes, and SA-, JA- and ET-associated genes. By contrast, virus-induced gene silencing (VIGS) of CaWRKY27 increased the susceptibility of pepper plants to R. solanacearum infection. These results suggest that CaWRKY27 acts as a positive regulator in tobacco resistance responses to R. solanacearum infection through modulation of SA-, JA- and ET-mediated signaling pathways. © 2013 Scandinavian Plant Physiology Society.
Wu, Zhencai; Burns, Jacqueline K
2003-04-01
The genetics and expression of a lipid transfer protein (LTP) gene was examined during abscission of mature fruit of 'Valencia' orange. A cDNA encoding an LTP, CsLTP, was isolated from a cDNA subtraction library constructed from mature fruit abscission zones 48 h after application of a mature fruit-specific abscission agent, 5-chloro-3-methyl-4-nitro-pyrazole (CMN-pyrazole). A full-length cDNA clone of 652 nucleotides was isolated using 5' and 3' RACE followed by cDNA library screening and PCR amplification. The cDNA clone encoded a protein of 155 amino acid residues with a molecular mass and isoelectric point of 9.18 kDa and 9.12, respectively. A partial genomic clone of 505 nucleotides containing one intron of 101 base pairs was amplified from leaf genomic DNA. Southern blot hybridization demonstrated that at least two closely related CsLTP genes are present in 'Valencia' orange. Temporal expression patterns in mature fruit abscission zones were examined by northern hybridization. Increased expression of CsLTP mRNA was detected in RNA of mature fruit abscission zones 6, 24, 48, and 72 h after application of a non-specific abscission agent, ethephon. Low expression of CsLTP transcripts was observed after treatment of CMN-pyrazole until 24 h after application. After this time, expression markedly increased. The results suggest that CsLTP has a role in the abscission process, possibly by assisting transport of cutin monomers to the fracture plane of the abscission zone or through its anti-microbial activity by reducing the potential of microbial attack.
Puranik, Swati; Bahadur, Ranjit Prasad; Srivastava, Prem S; Prasad, Manoj
2011-10-01
The plant-specific NAC (NAM, ATAF, and CUC) transcription factors have diverse role in development and stress regulation. A transcript encoding NAC protein, termed SiNAC was identified from a salt stress subtractive cDNA library of S. italica seedling (Puranik et al., J Plant Physiol 168:280-287, 2011). This single/low copy gene containing four exons and four introns within the genomic-sequence encoded a protein of 462 amino acids. Structural analysis revealed that highly divergent C terminus contains a transmembrane domain. The NAC domain consisted of a twisted antiparallel beta-sheet packing against N terminal alpha helix on one side and a shorter helix on the other side. The domain was predicted to homodimerize and control DNA-binding specificity. The physicochemical features of the SiNAC homodimer interface justified the dimeric form of the predicted model. A 1539 bp fragment upstream to the start codon of SiNAC gene was cloned and in silico analysis revealed several putative cis-acting regulatory elements within the promoter sequence. Transactivation analysis indicated that SiNAC activated expression of reporter gene and the activation domain lied at the C terminal. The SiNAC:GFP was detected in the nucleus and cytoplasm while SiNAC ΔC(1-158):GFP was nuclear localized in onion epidermal cells. SiNAC transcripts mostly accumulated in young spikes and were strongly induced by dehydration, salinity, ethephon, and methyl jasmonate. These results suggest that SiNAC encodes a membrane associated NAC-domain protein that may function as a transcriptional activator in response to stress and developmental regulation in plants.
Loh, Swee Cheng; Thottathil, Gincy P; Othman, Ahmad Sofiman
2016-10-01
The natural rubber of Para rubber tree, Hevea brasiliensis, is the main crop involved in industrial rubber production due to its superior quality. The Hevea bark is commercially exploited to obtain latex, which is produced from the articulated secondary laticifer. The laticifer is well defined in the aspect of morphology; however, only some genes associated with its development have been reported. We successfully induced secondary laticifer in the jasmonic acid (JA)-treated and linolenic acid (LA)-treated Hevea bark but secondary laticifer is not observed in the ethephon (ET)-treated and untreated Hevea bark. In this study, we analysed 27,195 gene models using NimbleGen microarrays based on the Hevea draft genome. 491 filtered differentially expressed (FDE) transcripts that are common to both JA- and LA-treated bark samples but not ET-treated bark samples were identified. In the Eukaryotic Orthologous Group (KOG) analysis, 491 FDE transcripts belong to different functional categories that reflect the diverse processes and pathways involved in laticifer differentiation. In the Kyoto Encyclopedia of Genes and Genomes (KEGG) and KOG analysis, the profile of the FDE transcripts suggest that JA- and LA-treated bark samples have a sufficient molecular basis for secondary laticifer differentiation, especially regarding secondary metabolites metabolism. FDE genes in this category are from the cytochrome (CYP) P450 family, ATP-binding cassette (ABC) transporter family, short-chain dehydrogenase/reductase (SDR) family, or cinnamyl alcohol dehydrogenase (CAD) family. The data includes many genes involved in cell division, cell wall synthesis, and cell differentiation. The most abundant transcript in FDE list was SDR65C, reflecting its importance in laticifer differentiation. Using the Basic Local Alignment Search Tool (BLAST) as part of annotation and functional prediction, several characterised as well as uncharacterized transcription factors and genes were found in the dataset. Hence, the further characterization of these genes is necessary to unveil their role in laticifer differentiation. This study provides a platform for the further characterization and identification of the key genes involved in secondary laticifer differentiation. Copyright © 2016 Elsevier Masson SAS. All rights reserved.
Death of mitochondria during programmed cell death of leaf mesophyll cells.
Selga, Tūrs; Selga, Maija; Pāvila, Vineta
2005-12-01
The role of plant mitochondria in the programmed cell death (PCD) is widely discussed. However, spectrum and sequence of mitochondrial structural changes during different types of PCD in leaves are poorly described. Pea, cucumber and rye plants were grown under controlled growing conditions. A part of them were sprinkled with ethylene releaser to accelerate cell death. During yellowing the palisade parenchyma mitochondria were attracted to nuclear envelope. Mitochondrial matrix became electron translucent. Mitochondria entered vacuole by invagination of tonoplast and formed multivesicular bodies. Ethephon treatment increased the frequency of sticking of mitochondria to the nuclear envelope or chloroplasts and peroxisomes. Mitochondria divided by different mechanisms and became enclosed in Golgi and ER derived authopagic vacuoles or in the central vacuole. Several fold increase of the diameter of cristae became typical. In all cases mitochondria were attached to nuclear envelope. It can be considered as structural mechanism of promoting of PCD.
Liu, Xin; Guan, Huirui; Song, Min; Fu, Yanping; Han, Xiaomin; Lei, Meng; Ren, Jingyu; Guo, Bin; He, Wei; Wei, Yahui
2018-01-01
Stellera chamaejasme Linn, an important poisonous plant of the China grassland, is toxic to humans and livestock. The rapid expansion of S. chamaejasme has greatly damaged the grassland ecology and, consequently, seriously endangered the development of animal husbandry. To draft efficient prevention and control measures, it has become more urgent to carry out research on its adaptive and expansion mechanisms in different unfavorable habitats at the genetic level. Quantitative real-time polymerase chain reaction (qRT-PCR) is a widely used technique for studying gene expression at the transcript level; however, qRT-PCR requires reference genes (RGs) as endogenous controls for data normalization and only through appropriate RG selection and qRT-PCR can we guarantee the reliability and robustness of expression studies and RNA-seq data analysis. Unfortunately, little research on the selection of RGs for gene expression data normalization in S. chamaejasme has been reported. In this study, 10 candidate RGs namely, 18S , 60S , CYP , GAPCP1 , GAPDH2 , EF1B , MDH , SAND , TUA1 , and TUA6 , were singled out from the transcriptome database of S. chamaejasme , and their expression stability under three abiotic stresses (drought, cold, and salt) and three hormone treatments (abscisic acid, ABA; gibberellin, GA; ethephon, ETH) were estimated with the programs geNorm, NormFinder, and BestKeeper. Our results showed that GAPCP1 and EF1B were the best combination for the three abiotic stresses, whereas TUA6 and SAND , TUA1 and CYP , GAPDH2 and 60S were the best choices for ABA, GA, and ETH treatment, respectively. Moreover, GAPCP1 and 60S were assessed to be the best combination for all samples, and 18S was the least stable RG for use as an internal control in all of the experimental subsets. The expression patterns of two target genes ( P5CS2 and GI ) further verified that the RGs that we selected were suitable for gene expression normalization. This work is the first attempt to comprehensively estimate the stability of RGs in S. chamaejasme . Our results provide suitable RGs for high-precision normalization in qRT-PCR analysis, thereby making it more convenient to analyze gene expression under these experimental conditions.
Pan, Ya-Jie; Liu, Jia; Guo, Xiao-Rui; Zu, Yuan-Gang; Tang, Zhong-Hua
2015-05-01
Research on transcriptional regulation of terpenoid indole alkaloid (TIA) biosynthesis of the medicinal plant, Catharanthus roseus, has largely been focused on gene function and not clustering analysis of multiple genes at the transcript level. Here, more than ten key genes encoding key enzyme of alkaloid synthesis in TIA biosynthetic pathways were chosen to investigate the integrative responses to exogenous elicitor ethylene and copper (Cu) at both transcriptional and metabolic levels. The ethylene-induced gene transcripts in leaves and roots, respectively, were subjected to principal component analysis (PCA) and the results showed the overall expression of TIA pathway genes indicated as the Q value followed a standard normal distribution after ethylene treatments. Peak gene expression was at 15-30 μM of ethephon, and the pre-mature leaf had a higher Q value than the immature or mature leaf and root. Treatment with elicitor Cu found that Cu up-regulated overall TIA gene expression more in roots than in leaves. The combined effects of Cu and ethephon on TIA gene expression were stronger than their separate effects. It has been documented that TIA gene expression is tightly regulated by the transcriptional factor (TF) ethylene responsive factor (ERF) and mitogen-activated protein kinase (MAPK) cascade. The loading plot combination with correlation analysis for the genes of C. roseus showed that expression of the MPK gene correlated with strictosidine synthase (STR) and strictosidine b-D-glucosidase(SGD). In addition, ERF expression correlated with expression of secologanin synthase (SLS) and tryptophan decarboxylase (TDC), specifically in roots, whereas MPK and myelocytomatosis oncogene (MYC) correlated with STR and SGD genes. In conclusion, the ERF regulates the upstream pathway genes in response to heavy metal Cu mainly in C. roseus roots, while the MPK mainly participates in regulating the STR gene in response to ethylene in pre-mature leaf. Interestingly, the change in TIA accumulation does not correlate with expression of the associated genes. Our previous research found significant accumulation of vinblastine in response to high concentration of ethylene and Cu suggesting the involvement of posttranscriptional and posttranslational mechanisms in a spatial and temporal manner. In this study, meta-analysis reveals ERF and MPK form a positive feedback loop connecting two pathways actively involved in response of TIA pathway genes to ethylene and copper in C. roseus.
Zhang, Mengyan; Wang, Siyao; Yin, Jing; Li, Chunxiao; Zhan, Yaguang; Xiao, Jialei; Liang, Tian; Li, Xin
2016-09-01
Betula platyphylla is a rich repository of pharmacologically active secondary metabolites known as birch triterpenoids (TBP). Here, we cloned the squalene synthase (SS) and squalene epoxidase genetic (SE) sequences from B. platyphylla that encode the key enzymes that are involved in triterpenoid biosynthesis and analyzed the conserved domains and phylogenetics of their corresponding proteins. The full-length sequence of BpSS is 1588 bp with a poly-A tail, which contained an open reading frame (ORF) of 1241 bp that encoded a protein of 413 amino acids. Additionally, the BpSE full-length sequence of 2040 bp with a poly-A tail was also obtained, which contained an ORF of 1581 bp encoding a protein of 526 amino acids. Their organ-specific expression patterns in 4-week-old tissue culture seedlings of B. platyphylla were detected by real-time PCR and showed that they were all highly expressed in leaves, as compared to stem and root tissues. Additionaly, both BpSS and BpSE were enhanced following stimulation with ethephon and MeJA. The expression of BpSS was enhanced by ABA, whereas BpSE was not. The SA treatment did not affect the BpSS and BpSE transcripts notably. Using a genome walking approach, promoter sequences of 965 and 1193 bp, respectively, for BpSS and BpSE were isolated, and they revealed several key cis-regulatory elements known to be involved in the response to phytohormone and abiotic plant stress. We also found that the BpSS protein is localized in the cytoplasm. Opening reading frames of BpSS and BpSE were ligated into yeast expression plasmid pYES2 under control of GAL1 promoter and introduced into the yeast INVScl1 strain. The transformants were cultured for 12 h, the squalene content of galactose-induced BpSS expression yeast cells was 13.2 times of control (empty vector control yeast cells) by high-performance liquid chromatography (HPLC) test method. And, the squalene epoxidase activity of induced BpSE expression yeast cell was about 11.8 times of control. These indicated that we cloned birch BpSS and BpSE that were indeed involved in the synthesis of triteropenoids. This is the first report wherein SS and SE from B. platyphylla were cloned and may be of significant interest to understand the regulatory role of SS and SE in the triterpenoids biosynthesis of B. platyphylla. This is the first report wherein SS and SE from B. platyphylla were cloned and may be of significant interest to understand the regulatory role of SS and SE in the biosynthesis of birch triterpenoids.
Huang, Yacheng; Fang, Yongjun; Long, Xiangyu; Liu, Linya; Wang, Jia; Zhu, Jinheng; Ma, Yanyan; Qin, Yunxia; Qi, Jiyan; Hu, Xinwen; Tang, Chaorong
2018-06-01
Metallothioneins (MTs) as reactive oxygen species (ROS) scavengers play important roles in stress response and heavy metal homeostasis. In Hevea brasiliensis (the para rubber tree that is the source of commercial natural rubber) and in other trees, the functions of MTs are not well understood. Latex exudes when the rubber tree is tapped. The flow of latex and its regeneration can be enhanced by tapping, wounding and ethylene treatment, all of which produce ROS as a by-product. Here, we show the presence of four MT genes in H. brasiliensis, comprising three Type 2 (HbMT2, -2a and -2b) and one Type 3 (HbMT3L) isoforms, representing one of the smallest MT gene families among angiosperms. The four HbMTs exhibited distinct tissue expression patterns: HbMT2 and HbMT3L mainly in leaves, HbMT2a specifically in flowers and HbMT2b in diverse tissues. The expression of HbMT2b, an isoform present in latex, decreased significantly in the latex following the stress-inducing treatments of tapping, wounding and ethephon (an ethylene generator). The expressions of the leaf-abundant isoforms, HbMT2 and -3L were up-regulated following pathogenic fungus infection and high-temperature stress, but down-regulated by low-temperature stress. These reactions were consistent with multiple defense- and hormone-responsive cis-acting elements in the HbMT promoters. Nine transcription factors were shown to implicate in the high-temperature responsiveness of HbMT2 and -3L in leaves. Overexpression of HbMT2 in Escherichia coli enhanced the bacterium's tolerance to heavy metals and ROS, consistent with its predicted role as an ROS scavenger. Taken together, our results, along with other relevant studies, suggest an important role of HbMTs in latex regeneration as well as species adaptation via the regulation of ROS homeostasis.
Bonvallot, Nathalie; Canlet, Cécile; Blas-Y-Estrada, Florence; Gautier, Roselyne; Tremblay-Franco, Marie; Chevolleau, Sylvie; Cordier, Sylvaine; Cravedi, Jean-Pierre
2018-01-01
The use of pesticides exposes humans to numerous harmful molecules. Exposure in early-life may be responsible for adverse effects in later life. This study aimed to assess the metabolic modifications induced in pregnant rats and their offspring by a pesticide mixture representative of human exposure. Ten pregnant rats were exposed to a mixture of eight pesticides: acetochlor (246 μg/kg bw/d) + bromoxynil (12 μg/kg bw/d) + carbofuran (22.5 μg/kg bw/d) + chlormequat (35 μg/kg bw/d) + ethephon (22.5 μg/kg bw/d) + fenpropimorph (15.5 μg/kg bw/d) + glyphosate (12 μg/kg bw/d) + imidacloprid (12.5 μg/kg bw/d) representing the main environmental pesticide exposure in Brittany (France) in 2004. Another group of 10 pregnant rats served as controls. Females were fed ad libitum from early pregnancy, which is from gestational day (GD) 4 to GD 21. Urine samples were collected at GD 15. At the end of the exposure, mothers and pups were euthanized and blood, liver, and brain samples collected. 1H NMR-based metabolomics and GC-FID analyses were performed and PCA and PLS-DA used to discriminate between control and exposed groups. Metabolites for which the levels were significantly modified were then identified using the Kruskal-Wallis test, and p-values were adjusted for multiple testing correction using the False Discovery Rate. The metabolomics analysis revealed many differences between dams of the two groups, especially in the plasma, liver and brain. The modified metabolites are involved in TCA cycle, energy production and storage, lipid and carbohydrate metabolism, and amino-acid metabolism. These modifications suggest that the pesticide mixture may induce oxidative stress associated with mitochondrial dysfunction and the impairment of glucose and lipid metabolism. These observations may reflect liver dysfunction with increased relative liver weight and total lipid content. Similar findings were observed for glucose and energy metabolism in the liver of the offspring, and oxidative stress was also suggested in the brains of male offspring.
Hormonal and metabolic regulation of tomato fruit sink activity and yield under salinity
Albacete, Alfonso; Cantero-Navarro, Elena; Balibrea, María E.; Großkinsky, Dominik K.; de la Cruz González, María; Martínez-Andújar, Cristina; Smigocki, Ann C.; Roitsch, Thomas; Pérez-Alfocea, Francisco
2014-01-01
Salinization of water and soil has a negative impact on tomato (Solanum lycopersicum L.) productivity by reducing growth of sink organs and by inducing senescence in source leaves. It has been hypothesized that yield stability implies the maintenance or increase of sink activity in the reproductive structures, thus contributing to the transport of assimilates from the source leaves through changes in sucrolytic enzymes and their regulation by phytohormones. In this study, classical and functional physiological approaches have been integrated to study the influence of metabolic and hormonal factors on tomato fruit sink activity, growth, and yield: (i) exogenous hormones were applied to plants, and (ii) transgenic plants overexpressing the cell wall invertase (cwInv) gene CIN1 in the fruits and de novo cytokinin (CK) biosynthesis gene IPT in the roots were constructed. Although salinity reduces fruit growth, sink activity, and trans-zeatin (tZ) concentrations, it increases the ethylene precursor 1-aminocyclopropane-1-carboxylic acid (ACC) during the actively growing period (25 days after anthesis). Indeed, exogenous application of the CK analogue kinetin to salinized actively growing fruits recovered sucrolytic activities (mainly cwInv and sucrose synthase), sink strength, and fruit weight, whereas the ethylene-releasing compound ethephon had a negative effect in equivalent non-stressed fruits. Fruit yield was increased by both the constitutive expression of CIN1 in the fruits (up to 4-fold) or IPT in the root (up to 30%), owing to an increase in the fruit number (lower flower abortion) and in fruit weight. This is possibly related to a recovery of sink activity in reproductive tissues due to both (i) increase in sucrolytic activities (cwInv, sucrose synthase, and vacuolar and cytoplasmic invertases) and tZ concentration, and (ii) a decrease in the ACC levels and the activity of the invertase inhibitor. This study provides new functional evidences about the role of metabolic and hormonal inter-regulation of local sink processes in controlling tomato fruit sink activity, growth, and yield under salinity. PMID:25170099
Wu, Jianyang; Zhang, Hongna; Liu, Liqin; Li, Weicai; Wei, Yongzan; Shi, Shengyou
2016-01-01
Reverse transcription quantitative PCR (RT-qPCR) as the accurate and sensitive method is use for gene expression analysis, but the veracity and reliability result depends on whether select appropriate reference gene or not. To date, several reliable reference gene validations have been reported in fruits trees, but none have been done on preharvest and postharvest longan fruits. In this study, 12 candidate reference genes, namely, CYP, RPL, GAPDH, TUA, TUB, Fe-SOD, Mn-SOD, Cu/Zn-SOD, 18SrRNA, Actin, Histone H3, and EF-1a, were selected. Expression stability of these genes in 150 longan samples was evaluated and analyzed using geNorm and NormFinder algorithms. Preharvest samples consisted of seven experimental sets, including different developmental stages, organs, hormone stimuli (NAA, 2,4-D, and ethephon) and abiotic stresses (bagging and girdling with defoliation). Postharvest samples consisted of different temperature treatments (4 and 22°C) and varieties. Our findings indicate that appropriate reference gene(s) should be picked for each experimental condition. Our data further showed that the commonly used reference gene Actin does not exhibit stable expression across experimental conditions in longan. Expression levels of the DlACO gene, which is a key gene involved in regulating fruit abscission under girdling with defoliation treatment, was evaluated to validate our findings. In conclusion, our data provide a useful framework for choice of suitable reference genes across different experimental conditions for RT-qPCR analysis of preharvest and postharvest longan fruits. PMID:27375640
Ethylene Response Factors Are Controlled by Multiple Harvesting Stresses in Hevea brasiliensis
Putranto, Riza-Arief; Duan, Cuifang; Kuswanhadi; Chaidamsari, Tetty; Rio, Maryannick; Piyatrakul, Piyanuch; Herlinawati, Eva; Pirrello, Julien; Dessailly, Florence; Leclercq, Julie; Bonnot, François; Tang, Chaorong; Hu, Songnian; Montoro, Pascal
2015-01-01
Tolerance of recurrent mechanical wounding and exogenous ethylene is a feature of the rubber tree. Latex harvesting involves tapping of the tree bark and ethephon is applied to increase latex flow. Ethylene is an essential element in controlling latex production. The ethylene signalling pathway leads to the activation of Ethylene Response Factor (ERF) transcription factors. This family has been identified in Hevea brasiliensis. This study set out to understand the regulation of ERF genes during latex harvesting in relation to abiotic stress and hormonal treatments. Analyses of the relative transcript abundance were carried out for 35 HbERF genes in latex, in bark from mature trees and in leaves from juvenile plants under multiple abiotic stresses. Twenty-one HbERF genes were regulated by harvesting stress in laticifers, revealing an overrepresentation of genes in group IX. Transcripts of three HbERF-IX genes from HbERF-IXc4, HbERF-IXc5 and HbERF-IXc6 were dramatically accumulated by combining wounding, methyl jasmonate and ethylene treatments. When an ethylene inhibitor was used, the transcript accumulation for these three genes was halted, showing ethylene-dependent induction. Subcellular localization and transactivation experiments confirmed that several members of HbERF-IX are activator-type transcription factors. This study suggested that latex harvesting induces mechanisms developed for the response to abiotic stress. These mechanisms probably depend on various hormonal signalling pathways. Several members of HbERF-IX could be essential integrators of complex hormonal signalling pathways in Hevea. PMID:25906196
Manzano, Susana; Martínez, Cecilia; García, Juan Manuel; Megías, Zoraida; Jamilena, Manuel
2014-12-01
Although it is known that ethylene has a masculinizing effect on watermelon, the specific role of this hormone in sex expression and flower development has not been analyzed in depth. By using different approaches the present work demonstrates that ethylene regulates differentially two sex-related developmental processes: sexual expression, i.e. the earliness and the number of female flowers per plant, and the development of individual floral buds. Ethylene production in the shoot apex as well as in male, female and bisexual flowers demonstrated that the female flower requires much more ethylene than the male one to develop, and that bisexual flowers result from a decrease in ethylene production in the female floral bud. The occurrence of bisexual flowers was found to be associated with elevated temperatures in the greenhouse, concomitantly with a reduction of ethylene production in the shoot apex. External treatments with ethephon and AVG, and the use of Cucurbita rootstocks with different ethylene production and sensitivity, confirmed that, as occurs in other cucurbit species, ethylene is required to arrest the development of stamens in the female flower. Nevertheless, in watermelon ethylene inhibits the transition from male to female flowering and reduces the number of pistillate flowers per plant, which runs contrary to findings in other cucurbit species. The use of Cucurbita rootstocks with elevated ethylene production delayed the production of female flowers but reduced the number of bisexual flowers, which is associated with a reduced fruit set and altered fruit shape.
Improving the Performance of Semiconductor Sensor Devices Using Surface Functionalization
NASA Astrophysics Data System (ADS)
Rohrbaugh, Nathaniel W.
As production and understanding of III-nitride growth has progressed, this class of material has been used for its semiconducting properties in the fields of computer processing, microelectronics, and LEDs. As understanding of materials properties has advanced, devices were fabricated to be sensitive to environmental surroundings such as pH, gas, or ionic concentration. Simultaneously the world of pharmaceuticals and environmental science has come to the age where the use of wearable devices and active environmental sensing can not only help us learn more about our surroundings, but help save lives. At the crossroads of these two fields work has been done in marrying the high stability and electrical properties of the III-nitrides with the needs of a growing sensor field for various environments and stimuli. Device architecture can only get one so far, and thus the need for well understood surface functionalization techniques has arisen in the field of III-nitride environmental sensing. Many existing schemes for functionalization involve chemistries that may be unfriendly to a biological environment, unstable in solution, or expensive to produce. One possible solution to these issues is the work presented here, which highlights a surface modification scheme utilizing phosphonic acid based chemistry and biomolecular attachment. This dissertation presents a set of studies and experiments quantifying and analyzing the response behaviors of AlGaN/GaN field effect transistor (FET) devices via their interfacial electronic properties. Additional investigation was done on the modification of these surfaces, effects of stressful environmental conditions, and the utility of the phosphonic acid surface treatments. Signals of AlGaN/GaN FETs were measured as IDrain values and in the earliest study an average signal increase of 96.43% was observed when surfaces were incubated in a solution of a known recognition peptide sequence (SVSVGMKPSPRP). This work showed that even without a form of surface modification the devices were capable of generating a response in the presence of a charged biomolecule. Solution exposure tests done devices showed that incubating peptides on the device surfaces produced a weak interaction and following 24 hrs of soaking no signs of peptide remained via XPS analysis. Subsequent testing was done to incorporate the phosphonic acid functionalization techniques shown previously by other members of this lab to the AlGaN/GaN surfaces as a remedy to this solution instability. In this second study FETs were modified using a heated phosphoric acid:ethephon etch followed by an incubation in TAT-C peptide. Resulting IV measurements done on the samples showed a shift in threshold voltage of the FETs following the etching procedure followed by a recovery of this shift from prolonged solution exposure. In total samples were given 168 hours of soaking and showed persistent peptide presence through the N 1s peak from XPS scans. FETs modified with this phosphonic acid derivative were examined in a third study under a simulated pollutant sensing scenario by measuring varied concentrations of Hg via a phytochelatin peptide bound to FET surfaces. HNO3 used in the Hg stock solution led to degradation of the FET signal but did not remove the phytochelatin layer. This led to a compensation effect in sensing the highest levels of Hg, lower concentrations however were successfully tested and showed varied responses from the FETs relative to the Hg content. In a concluding study on devices work was done to understand broader effects on the AlGaN/GaN FETs relative to a simulated biological sensing environment. Here an effect was noted from the addition of a biological fouling solution to the FETs and an increase in this effect when the biofouling was done to a phosphonic modified FET surface. Additionally devices were modified and soaked for 5 weeks and showed no shift or degradation in signal. Lastly in controlling for gate width of the FET it was found that the shorter 50 im gates were more susceptible to environmental interference than the 100 and 150 im gated devices. Thus this work has shown that modifying AlGaN/GaN devices with phosphonic acid derivatives is a viable functionalization method that is both adaptable and stable in solution over time. In moving forward, opportunities are available for testing a larger variety of analytes in both the medical and environmental fields. The final goal for this technology would be the fabrication and design of a multi-device sensing unit leading to eventual production of these sensors on an industrial scale for the use in future personal medical devices or environmental monitoring systems.
Oh, Sang-Keun; Yoon, Joonseon; Choi, Gyung Ja; Jang, Hyun A; Kwon, Suk-Yoon; Choi, Doil
2013-12-06
Homeodomain-leucine zipper (HD-Zip) family proteins are unique to plants, but little is known about their role in defense responses. CaHB1 is a nuclear factor in peppers, belonging to subfamily II of HD-Zip proteins. Here, we determined the role of CaHB1 in the defense response. CaHB1 expression was induced when pepper plants were challenged with Phytophthora capsici, a plant pathogen to which peppers are susceptible, or environmental stresses such as drought and salt stimuli. CaHB1 was also highly expressed in pepper leaves following application of SA, whereas ethephon and MeJA had a moderate effect. To further investigate the function of CaHB1 in plants, we performed gain-of-function study by overexpression of CaHB1 in tomato. CaHB1-transgenic tomatoes showed significant growth enhancement including increased leaf thickness and enlarged cell size (1.8-fold larger than control plants). Microscopic analysis revealed that leaves from CaHB1-transgenic plants had thicker cell walls and cuticle layers than those from controls. Moreover, CaHB1-transgenic plants displayed enhanced resistance against Phytophthora infestans and increased tolerance to salt stress. Additionally, RT-PCR analysis of CaHB1-transgenic tomatoes revealed constitutive up-regulation of multiple genes involved in plant defense and osmotic stress. Therefore, our findings suggest roles for CaHB1 in development, salt stress, and pathogen defense. Copyright © 2013 Elsevier Inc. All rights reserved.
Rawat, Reetika; Xu, Zeng-Fu; Yao, Kwok-Ming; Chye, Mee-Len
2005-03-01
We have previously shown that the expression of SmCP which encodes Solanum melongena cysteine proteinase is ethylene-inducible and is under circadian control. To understand the regulation of SmCP, a 1.34-kb SmCP 5'-flanking region and its deletion derivatives were analyzed for cis-elements using GUS and luc fusions and by in vitro binding assays. Analysis of transgenic tobacco transformed with SmCP promoter-GUS constructs confirmed that the promoter region -415/+54 containing Ethylene Responsive Element ERE(-355/-348) conferred threefold ethylene-induction of GUS expression, while -827/+54 which also contains ERE(-683/-676), produced fivefold induction. Using gel mobility shift assays, we demonstrated that each ERE binds nuclear proteins from both ethephon-treated and untreated 5-week-old seedlings, suggesting that different transcriptions factors bind each ERE under varying physiological conditions. Binding was also observed in extracts from senescent, but not young, fruits. The variation in binding at the EREs in fruits and seedlings imply that organ-specific factors may participate in binding. Analysis of transgenic tobacco expressing various SmCP promoter-luc constructs containing wild-type or mutant Evening Elements (EEs) confirmed that both conserved EEs at -795/-787 and -785/-777 are important in circadian control. We confirmed the binding of total nuclear proteins to EEs in gel mobility shift assays and in DNase I footprinting. Our results suggest that multiple proteins bind the EEs which are conserved in plants other than Arabidopsis and that functional EEs and EREs are present in the 5'-flanking region of a gene encoding cysteine proteinase.
Solid-phase extraction of acidic herbicides.
Wells, M J; Yu, L Z
2000-07-14
A discussion of solid-phase extraction method development for acidic herbicides is presented that reviews sample matrix modification, extraction sorbent selection, derivatization procedures for gas chromatographic analysis, and clean-up procedures for high-performance liquid chromatographic analysis. Acidic herbicides are families of compounds that include derivatives of phenol (dinoseb, dinoterb and pentachlorophenol), benzoic acid (acifluorfen, chloramben, dicamba, 3,5-dichlorobenzoic acid and dacthal--a dibenzoic acid derivative), acetic acid [2,4-dichlorophenoxyacetic acid (2,4-D), 4-chloro-2-methylphenoxyacetic acid (MCPA) and 2,4,5-trichlorophenoxyacetic acid (2,4,5-T)], propanoic acid [dichlorprop, fluazifop, haloxyfop, 2-(4-chloro-2-methylphenoxy)propanoic acid (MCPP) and silvex], butanoic acid [4-(2,4-dichlorophenoxy)butanoic acid (2,4-DB) and 4-(4-chloro-2-methylphenoxy)butanoic acid (MCPB)], and other miscellaneous acids such as pyridinecarboxylic acid (picloram) and thiadiazine dioxide (bentazon).
Cox-2 inhibitory effects of naturally occurring and modified fatty acids.
Ringbom, T; Huss, U; Stenholm , A; Flock, S; Skattebøl, L; Perera, P; Bohlin, L
2001-06-01
In the search for new cyclooxygenase-2 (COX-2) selective inhibitors, the inhibitory effects of naturally occurring fatty acids and some of their structural derivatives on COX-2-catalyzed prostaglandin biosynthesis were investigated. Among these fatty acids, linoleic acid (LA), alpha-linolenic acid (alpha-LNA), myristic acid, and palmitic acid were isolated from a CH(2)Cl(2) extract of the plant Plantago major by bioassay-guided fractionation. Inhibitory effects of other natural, structurally related fatty acids were also investigated: stearic acid, oleic acid, pentadecanoic acid, eicosapentaenoic acid (EPA), and docosahexaenoic acid (DHA). Further, the inhibitory effects of these compounds on COX-2- and COX-1-catalyzed prostaglandin biosynthesis was compared with the inhibition of some synthesized analogues of EPA and DHA with ether or thioether functions. The most potent COX-2-catalyzed prostaglandin biosynthesis inhibitor was all-(Z)-5-thia-8,11,14,17-eicosatetraenoic acid (2), followed by EPA, DHA, alpha-LNA, LA, (7E,11Z,14Z,17Z)-5-thiaeicosa-7,11,14,17-tetraenoic acid, all-(Z)-3-thia-6,9,12,15-octadecatetraenoic acid, and (5E,9Z,12Z,15Z,18Z)-3-oxaheneicosa-5,9,12,15,18-pentaenoic acid, with IC(50) values ranging from 3.9 to180 microM. The modified compound 2 and alpha-LNA were most selective toward COX-2, with COX-2/COX-1 ratios of 0.2 and 0.1, respectively. This study shows that several of the natural fatty acids as well as all of the semisynthetic thioether-containing fatty acids inhibited COX-2-catalyzed prostaglandin biosynthesis, where alpha-LNA and compound 2 showed selectivity toward COX-2.
Electrophilic properties of common MALDI matrix molecules
NASA Astrophysics Data System (ADS)
Lippa, T. P.; Eustis, S. N.; Wang, D.; Bowen, K. H.
2007-11-01
The negative ion photoelectron spectra of the following MALDI matrix molecules have been measured: 3-carboxypyridine (nicotinic acid), 2,5-dihydroxybenzoic acid (DHB), 3,5-dimethoxy-4-hydroxycinnamic acid (sinapinic acid), 2,6-dihydroxyacetophenone (DHAP), 3-(4-hydroxy-3-methoxyphenyl)-2-propenoic acid (ferulic acid), 3-hydroxy-2-pyridinecarboxylic acid (3HPA), and 2,6-pyridinedicarboxylic acid (dipicolinic acid). Adiabatic electron affinities and vertical detachment energies were extracted from these spectra and reported. In addition, electron affinities were calculated for DHAP, ferulic acid, dipicolinic acid and sinapinic acid. Photoelectron spectra were also measured for the dimer anions of DHB and nicotinic acid and for the fragment anion in which alpha-cyano-cinnamic acid had lost a CO2 unit. Together, these results augment the database of presently available electrophilic data on common matrix molecules along with some of their dimers and fragments.
The role of ethylene in the development of constant-light injury of potato and tomato
NASA Technical Reports Server (NTRS)
Cushman, K. E.; Tibbitts, T. W.
1998-01-01
The role of ethylene in the development of constant-light injury of potato (Solanum tuberosum L.) and tomato (Lycopersicon esculentum Mill.) was investigated. In one study, silver thiosulfate (STS) was applied to the foliage of four potato cultivars growing under constant light. Leaf area and shoot dry mass of 'Kennebec' and 'Superior', cultivars normally injured by constant light, were greater (P < 0.05) than those of control plants given foliar applications of distilled water. Examination of STS-treated 'Kennebec' leaflets revealed significantly less injury (necrotic spotting and reduced starch content) than the water-treated controls. 'Norland' and 'Denali', cultivars tolerant of constant light, exhibited no differences in growth between treatments. In a second study, injury (necrotic spotting and reduced starch content) was induced in leaflets of 'Denali' when exposed to spray applications of 0.5 mmol L-1 ethephon or air containing 0.5 to 0.8 microL L-1 ethylene. In a third study, three genotypes of 'Ailsa Craig' tomato were grown under constant light. Leaves of the normal 'Ailsa Craig' exhibited epinasty, reduced chlorophyll concentration, and reduced starch content. Leaves of a mutant 'Ailsa Craig', containing the Never ripe mutation, did not exhibit epinasty but exhibited the same amount of reduced chlorophyll concentration and starch content as normal plants. Leaves of a transgenic 'Ailsa Craig', containing an antisense gene of 1-aminocyclopropane 1-carboxylate (ACC) oxidase, were epinastic, but chlorophyll concentration and starch content were greater than in leaves of normal and mutant plants. These results suggest that transgenic plants were more tolerant of constant light than the other genotypes. Evidence from these studies indicates that ethylene, combined with constant light, has an important role in the development of constant-light injury.
[Determination of peracetic acid and hydrogen peroxide in a preparation].
Bodiroga, Milanka; Ognjanović, Jasminka
2002-01-01
Iodometric and permanganometric titrations were used for determination of peracetic acid and hydrogen peroxide (H2O2) in the mixture. Two procedures were described and compared. Titrations could be done in only one vessel, in the same reaction mixture, when iodometric titration of peracetic acid was continued after the permanganometric titration of H2O2, (procedure A). Peracetic acid and H2O2, as oxidizing agents, reacted with potassium iodide in an acid medium, evolving iodine. This reaction was used for the quantitative iodometric determination of total peroxide in procedure B. H2O2 reacted with potassium permanganate in acid medium, but peracetic acid did not react under the same conditions. That made possible the selective permanganometric determination of H2O2 in the presence of peracetic acid. The procedure B was performed in two titration vessels (KV = 3.4% for peracetic acid, 0.6% for H2O2). The procedure A for iodometric determination of peracetic acid in one titration vessel after permanganometric titration of H2O2 was recommended (KV = 2.5% for peracetic acid, 0.45% for H2O2).
Singh, Namrata; Bhattacharyya, Debasish
2016-04-15
An ether extract of nine different bacterial metabolites in combination with two solvent extract (ether followed by ethanol) of bile lipids from ox gall bladder is used as an immune stimulator drug. Over the years bile acids are discussed regarding their anti-oxidant and lipid peroxidation properties. Since some of the bile acids are known to be potent antioxidants, presence of similar activity in the solvent extract of ox bile lipid was investigated using TLC and reverse phase HPLC systems. Fractions from HPLC were analyzed with mass spectrometry using electrospray ionization. The presence of twelve different bile acids along with other substances in small proportions including fatty acids, sulfate conjugates and bile pigments were confirmed. The twelve separated peaks had similar retention times as those of tauroursodeoxycholic acid, glycoursodeoxycholic acid, taurocholic acid, glycocholic acid, glycochenodeoxycholic acid, taurochenodeoxycholic acid, taurodeoxycholic acid, cholic acid, ursodeoxycholic acid, chenodeoxycholic acid, deoxycholic acid, and lithocholic acid. Subsequently, all fractions were tested for their anti-oxidative property on HepG2 cells exposed to H2O2 that served as an oxidative injury model. Four fluorescent dyes H2DCF DA, MitoSOX red, Amplex red and DAF-2 DA were used for estimation of reactive radicals in the HepG2 cells. Among the separated bile acids, tauroursodeoxycholic acid, glycoursodeoxycholic acid and ursodeoxycholic acid prevented the HepG2 cells from H2O2-induced oxidative stress. Copyright © 2015 Elsevier B.V. All rights reserved.
NASA Astrophysics Data System (ADS)
Zhang, Jing; Jin, Shouwen; Tao, Lin; Liu, Bin; Wang, Daqi
2014-08-01
Eight supramolecular complexes with 2-methylquinoline and acidic components as 4-aminobenzoic acid, 2-aminobenzoic acid, salicylic acid, 5-chlorosalicylic acid, 3,5-dinitrosalicylic acid, malic acid, sebacic acid, and 1,5-naphthalenedisulfonic acid were synthesized and characterized by X-ray crystallography, IR, mp, and elemental analysis. All of the complexes are organic salts except compound 2. All supramolecular architectures of 1-8 involve extensive classical hydrogen bonds as well as other noncovalent interactions. The results presented herein indicate that the strength and directionality of the classical hydrogen bonds (ionic or neutral) between acidic components and 2-methylquinoline are sufficient to bring about the formation of binary organic acid-base adducts. The role of weak and strong noncovalent interactions in the crystal packing is ascertained. These weak interactions combined, the complexes 1-8 displayed 2D-3D framework structure.
Huang, Yu-Ting; Onose, Jun-ichi; Abe, Naoki; Yoshikawa, Kunie
2009-04-23
Increasing attention has been focused on food-drug interactions. We have investigated the inhibitory effect of Chinese edible mushrooms, Boletus calopus and Suillus bovinus, on cytochrome P450 (CYP) 1A2, 2C9, 2D6, and 3A4, the main drug-metabolizing enzymes. Three pulvinic acid derivatives, atromentic acid (1), variegatic acid (2), and xerocomic acid (3), isolated from Boletus calopus and Suillus bovinus, revealed nonspecific inhibitory effects on all four CYPs. Using these compounds, the maximum IC50 values obtained with CYP3A4 in vitro were atromentic acid (1), 65.1+/-3.9 microM; variegatic acid (2), 2.2+/-0.1 microM; and xerocomic acid (3), 2.4+/-0.1 microM. Variegatic acid (2) and xerocomic acid (3) were effective inhibitors, comparable to cimetidine, dicoumarol, erythromycin, safrole, and uniconazole. Variegatic acid (2) and xerocomic acid (3) efficiently reduced ferryl myoglobin in CYPs. Reduction of ferryl heme to ferric heme is likely the mechanism of the nonspecific inhibitory effects of these compounds on CYPs.
Liao, James C.; Cho, Kwang Myung; Yan, Yajun; Huo, Yixin
2016-03-15
Provided herein are metabolically modified microorganisms characterized by having an increased keto-acid flux when compared with the wild-type organism and comprising at least one polynucleotide encoding an enzyme that when expressed results in the production of a greater quantity of a chemical product when compared with the wild-type organism. The recombinant microorganisms are useful for producing a large number of chemical compositions from various nitrogen containing biomass compositions and other carbon sources. More specifically, provided herein are methods of producing alcohols, acetaldehyde, acetate, isobutyraldehyde, isobutyric acid, n-butyraldehyde, n-butyric acid, 2-methyl-1-butyraldehyde, 2-methyl-1-butyric acid, 3-methyl-1-butyraldehyde, 3-methyl-1-butyric acid, ammonia, ammonium, amino acids, 2,3-butanediol, 1,4-butanediol, 2-methyl-1,4-butanediol, 2-methyl-1,4-butanediamine, isobutene, itaconate, acetoin, acetone, isobutene, 1,5-diaminopentane, L-lactic acid, D-lactic acid, shikimic acid, mevalonate, polyhydroxybutyrate (PHB), isoprenoids, fatty acids, homoalanine, 4-aminobutyric acid (GABA), succinic acid, malic acid, citric acid, adipic acid, p-hydroxy-cinnamic acid, tetrahydrofuran, 3-methyl-tetrahydrofuran, gamma-butyrolactone, pyrrolidinone, n-methylpyrrolidone, aspartic acid, lysine, cadeverine, 2-ketoadipic acid, and/or S-adenosyl-methionine (SAM) from a suitable nitrogen rich biomass.
Aerobic biodegradation of 2,2'-dithiodibenzoic acid produced from dibenzothiophene metabolites
DOE Office of Scientific and Technical Information (OSTI.GOV)
Young, R.F.; Cheng, S.M.; Fedorak, P.M.
Dibenzothiophene is a sulfur heterocycle found in crude oils and coal. The biodegradation of dibenzothiophene through the Kodama pathway by Pseudomonas sp. strain BT1d leads to the formation of three disulfides: 2-oxo-2-(2-thiophenyl)ethanoic acid disulfide, 2-oxo-2-(2-thiophenyl)ethanoic acid-2-benzoic acid disulfide, and 2,2'-dithiodibenzoic acid. When provided as the carbon and sulfur source in liquid medium, 2,2'-dithiodibenzoic acid was degraded by soil enrichment cultures. Two bacterial isolates, designated strains RM1 and RM6, degraded 2,2'-dithiodibenzoic acid when combined in the medium. Isolate RM6 was found to have an absolute requirement for vitamin B{sub 12}, and it degraded 2,2'-dithiodibenzoic acid in pure culture when the mediummore » was supplemented with this vitamin. Isolate RM6 also degraded 2,2'-dithiodibenzoic acid in medium containing sterilized supernatants from cultures of isolate RM1 grown on glucose or benzoate. Isolate RM6 was identified as a member of the genus Variovorax using the Biolog system and 16S rRNA gene analysis. Although the mechanism of disulfide metabolism could not be determined, benzoic acid was detected as a transient metabolite of 2,2'-dithiodibenzoic acid biodegradation by Variovorax sp. strain RM6. In pure culture, this isolate mineralized 2,2'-dithiodibenzoic acid, releasing 59% of the carbon as carbon dioxide and 88% of the sulfur as sulfate.« less
Ren, Wan-Xia; Li, Pei-Jun; Zheng, Le; Fan, Shu-Xiu; Verhozina, V A
2009-02-15
A few researchers have reported on work concerning bioleaching of heavy-metal-contaminated soil using Acidithiobacillus ferrooxidans, since this acidophile is sensitive to dissolved low molecular weight (LMW) organic acids. Iron oxidation by A. ferrooxidans R2 as well as growth on ferrous iron was inhibited by a variety of dissolved LMW organic acids. Growth experiments with ferrous iron as an oxidant showed that the inhibition capability sequence was formic acid>acetic acid>propionic acid>oxalic acid>malic acid>citric acid. The concentrations that R2 might tolerate were formic acid 0.1mmolL(-1) (2mmolkg(-1)soil), acetic and propionic acids 0.4mmolL(-1) (8mmolkg(-1)soil), oxalic acid 2.0mmolL(-1) (40mmolkg(-1)soil), malic acid 20mmolL(-1) (400mmolkg(-1)soil), citric acid 40mmolL(-1) (800mmolkg(-1)soil), respectively. Although R2 was sensitive to organic acids, the concentrations of LMW organic acids in the contaminated soils were rather lower than the tolerable levels. Hence, it is feasible that R2 might be used for bioleaching of soils contaminated with metals or metals coupled with organic compounds because of the higher concentrations of LMW organic acids to which R2 is tolerant.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Li, Zhong; Matus, Myrna H; Velazquez, Hector A
Gas-phase acidities (GA or ΔG acid) for the two most acidic common amino acids, aspartic acid and glutamic acid, have been determined for the first time. Because of the amide linkage’s importance in peptides and as an aid in studying side chain versus main chain deprotonation, aspartic acid amide and glutamic acid amide were also studied. Experimental GA values were measured by proton transfer reactions in an electrospray ionization/Fourier transform ion cyclotron resonance mass spectrometer. Calculated GAs were obtained by density functional and molecular orbital theory approaches. The best agreement with experiment was found at the G3MP2 level; the MP2/CBSmore » and B3LYP/aug-cc-pVDZ results are 3–4 kcal/mol more acidic than the G3MP2 results. Experiment shows that aspartic acid is more acidic than glutamic acid by ca. 3 kcal/mol whereas the G3MP2 results show a smaller acidity difference of 0.2 kcal/mol. Similarly, aspartic acid amide is experimentally observed to be ca. 2 kcal/mol more acidic than glutamic acid amide whereas the G3MP2 results show a correspondingly smaller energy difference of 0.7 kcal/mol. The computational results clearly show that the anions are all ring-like structures with strong hydrogen bonds between the OH or NH 2 groups and the CO 2 - group from which the proton is removed. The two amino acids are main-chain deprotonated. In addition, use of the COSMO model for the prediction of the free energy differences in aqueous solution gave values in excellent agreement with the most recent experimental values for pK a. Glutamic acid is predicted to be more acidic than aspartic acid in aqueous solution due to differential solvation effects.« less
Carballeira, Néstor M; Oyola, Delise; Vicente, Jan; Rodriguez, Abimael D
2007-11-01
The phospholipid fatty acid composition of the Caribbean sponge Erylus goffrilleri is described for the first time. A total of 70 fatty acids with chain lengths between 13 and 29 carbons were identified in the sponge. Methyl-branched fatty acids predominated in E. goffrilleri suggesting the presence of a considerable number of bacterial symbionts. The novel fatty acids (5Z,9Z)-2-methoxy-5,9-hexadecadienoic acid, (5Z,9Z)-2-methoxy-5,9-octadecadienoic acid, (5Z,9Z)-2-methoxy-5,9-nonadecadienoic acid, and (5Z,9Z)-2-methoxy-5,9-eicosadienoic acid are described for the first time in the literature. In addition, the iso-methyl-branched fatty acids (9Z)-2-methoxy-15-methyl-9-hexadecenoic acid and (5Z,9Z)-2-methoxy-15-methyl-5,9-hexadecadienoic acid, also identified in E. goffrilleri, were identified for the first time in nature. Based on the identified metabolites it is proposed that the unprecedented biosynthetic sequence: i-17:1Delta9 --> 2-OMe-i-17:1Delta9 --> 2-OMe-i-17:2Delta5,9 might be responsible for the biosynthesis of the novel iso-alpha-methoxylated fatty acids in E. goffrilleri.
Antagonism of histamine-activated adenylate cyclase in brain by D-lysergic acid diethylamide.
Green, J P; Johnson, C L; Weinstein, H; Maayani, S
1977-12-01
D-Lysergic acid diethylamide and D-2-bromolysergic acid diethylamide are competitive antagonists of the histamine activation of adenylate cyclase [ATP pyrophosphate-lyase (cyclizing); E.C. 4.6.1.1] in broken cell preparations of the hippocampus and cortex of guinea pig brain. The adenylate cyclase is linked to the histamine H2-receptor. Both D-lysergic acid diethylamide and D-2-bromolysergic acid diethylamide show topological congruency with potent H2-antagonists. D-2-Bromolysergic acid diethylamide is 10 times more potent as an H2-antagonist than cimetidine, which has been the most potent H2-antagonist reported, and D-lysergic acid diethylamide is about equipotent to cimetidine. Blockade of H2-receptors could contribute to the behavioral effects of D-2-bromolysergic acid diethylamide and D-lysergic acid diethylamide.
Shibata, Katsumi; Nakata, Chifumi; Fukuwatari, Tsutomu
2016-01-01
B-group vitamins are involved in the catabolism of 2-oxo acids. To identify the functional biomarkers of B-group vitamins, we developed a high-performance liquid chromatographic method for profiling 2-oxo acids in urine and applied this method to urine samples from rats deficient in vitamins B1 and B6 and pantothenic acid. 2-Oxo acids were reacted with 1,2-diamino-4,5-methylenebenzene to produce fluorescent derivatives, which were then separated using a TSKgel ODS-80Ts column with 30 mmol/L of KH2PO4 (pH 3.0):acetonitrile (7:3) at a flow rate of 1.0 mL/min. Vitamin B1 deficiency increased urinary levels of all 2-oxo acids, while vitamin B6 deficiency only increased levels of sum of 2-oxaloacetic acid and pyruvic acid, and pantothenic acid deficiency only increased levels of 2-oxoisovaleric acid. Profiles of 2-oxo acids in urine samples might be a non-invasive way of clarifying the functional biomarker of B-group vitamins.
Wegener, Steffen; Bornik, Maria-Anna; Kroh, Lothar W
2015-07-22
Thermal treatment of aqueous solutions of D-galacturonic acid and L-alanine at pH 3, 5, and 8 led to rapid and more intensive nonenzymatic browning reactions compared to similar solutions of other uronic acids and to Maillard reactions of reducing sugars. The hemiacetal ring structures of uronic acids had a high impact on browning behavior and reaction pathways. Besides reductic acid (1,2-dihydroxy-2-cyclopenten-1-one), 4,5-dihydroxy-2-cyclopenten-1-one (DHCP), furan-2-carboxaldehyde, and norfuraneol (4-hydroxy-5-methyl-3-(2H)-furanone) could be detected as typical products of nonenzymatic uronic acid browning reactions. 2-(2-Formyl-1H-pyrrole-1-yl)propanoic acid (FPA) and 1-(1-carboxyethyl)-3-hydroxypyridin-1-ium (HPA) were identified as specific reaction products of uronic acids with amine participation like l-alanine. In contrast, the structurally related D-galacturonic acid methyl ester showed less browning activity and degradation under equal reaction conditions. Pectin-specific degradation products such as 5-formyl-2-furanoic acid and 2-furanoic acid were found but could not be verified for d-galacturonic acid monomers alone.
Identification of dicarboxylic acids and aldehydes of PM10 and PM2.5 aerosols in Nanjing, China
NASA Astrophysics Data System (ADS)
Wang, Gehui; Niu, Sulian; Liu, Caie; Wang, Liansheng
In this study aerosol samples of PM10 and PM2.5 collected from 18 February 2001 to 1 May 2001 in Nanjing, China were analyzed for their water-soluble organic compounds. A series of homologous dicarboxylic acids (C 2-10) and two kinds of aldehydes (methylglyoxal and 2-oxo-malonaldehyde) were detected by GC and GC/MS. Among the identified compounds, the concentration of oxalic acid was the highest at all the five sites, which ranged from 178 to 1423 ng/m 3. The second highest concentration of dicarboxylic acids were malonic and succinic acids, which ranged from 26.9 to 243 ng/m 3. Higher level of azelaic acid was also observed, of which the maximum was 301 ng/m 3. As the highest fraction of dicarboxylic acids, oxalic acid comprised from 28% to 86% of total dicarboxylic acids in PM10 and from 41% to 65% of total dicarboxylic acids in PM2.5. The dicarboxylic acids (C 2, C 3, C 4) together accounted for 38-95% of total dicarboxylic acids in PM10 and 59-87% of dicarboxylic acids in PM2.5. In this study, the total dicarboxylic acids accounted for 2.8-7.9% of total organic carbon (TOC) of water-soluble matters for PM10 and 3.4-11.8% of TOC for PM2.5. All dicarboxylic acids detected in this study together accounted for about 1% of particle mass. The concentration of azelaic acid was higher at one site than others, which may be resulted from higher level of volatile fat used for cooking. The amounts of dicarboxyic acids (C 2,3,4,9) and 2-oxo-malonaldehyde of PM2.5 were higher in winter and lower in spring. Compared with other major metropolitans in the world, the level of oxalic acid concentration of Nanjing is much higher, which may be contributed to higher level of particle loadings, especially for fine particles.
Li, Mei; Li, Ji-Tai; Sun, Han-Wen
2008-07-01
At its natural pH (6.95), the decolorization of Reactive red 24 in ultrasound, ultrasound/H2O2, exfoliated graphite, ultrasound/exfoliated graphite, exfoliated graphite/H2O2 and ultrasound/exfoliated graphite/H2O2 systems were compared. An enhancement was observed for the decolorization in ultrasound/exfoliated graphite/H2O2 system. The effect of solution pH, H2O2 and exfoliated graphite dosages, and temperature on the decolorization of Reactive red 24 was investigated. The sonochemical treatment in combination with exfoliated graphite/H2O2 showed a synergistic effect for the decolorization of Reactive red 24. The results indicated that under proper conditions, there was a possibility to remove Reactive red 24 very efficient from aqueous solution. The decolorization of other azo dyes (Reactive red 2, Methyl orange, Acid red 1, Acid red 73, Acid red 249, Acid orange 7, Acid blue 113, Acid brown 75, Acid green 20, Acid yellow 42, Acid mordant brown 33, Acid mordant yellow 10 and Direct green 1) was also investigated, at their natural pH.
Fautz, E; Rosenfelder, G; Grotjahn, L
1979-01-01
The fatty acids present in the total hydrolysates of several gliding bacteria (Myxococcus fulvus, Stigmatella aurantiaca, Cytophaga johnsonae, Cytophaga sp. strain samoa and Flexibacter elegans) were analyzed by combined gas-liquid chromatography and mass spectrometry. In addition to 13-methyl-tetradecanoic acid, 15-methyl-hexadecanoic acid, hexadecanoic acid, and hexadecenoic acid, 2- and 3-hydroxy fatty acids comprised up to 50% of the total fatty acids. The majority was odd-numbered and iso-branched. Small amounts of even-numbered and unbranched fatty acids were also present. Whereas 2-hydroxy-15-methyl hexadecanoic acid was characteristic for myxobacteria, 2-hydroxy-13-methyl-tetradecanoic acid, 3-hydroxy-13-methyl-tetradecanoic acid, and 3-hydroxy-15-methyl-hexadecanoic acid were dominant in the Cytophaga-Flexibacter group. PMID:118159
Mastelić, Josip; Politeo, Olivera; Jerković, Igor
2008-04-07
The essential oil of Helichrysum italicum (Roth) G. Don (everlasting or Immortelle essential oil) was isolated by hydrodistillation and analysed by GC and GCMS. Forty four compounds were identified. The main components were alpha-pinene(12.8%), 2-methyl-cyclohexyl pentanoate (11.1 %), neryl acetate (10.4%), 1,7-di-epi-alpha-cedrene (6.8%) and other compounds. The oil was fractionated and ester-containing fraction was hydrolysed with KOH/H(2)SO(4). The liberated volatiles were analysed by GC and GC-MS: three phenols and twenty seven volatile carboxylic acids were identified[70% low fatty acids (C(2)-C(5)), 15% C(10)-C(12) acids and 15% other acids]. The main acids were acetic acid (24.3%) propanoic acid (17.2%), 2-methylpropanoic acid (11.4%),dodecanoic acid (8.7%), 2-methylbutanoic acid (8.3%), (Z)-2-methylbutenoic acid(5.1%) and decanoic acid (4.6%). With respect to the identified bonded carboxylic acids,the minimal number of esters in the oil was twenty seven, but their overall quantity was probably larger due to different possible combinations of alcohols with acids to form esters. On the other hand, only six main esters were identified in the oil before fractionation and hydrolysis.
NASA Astrophysics Data System (ADS)
Xu, Dandan; He, Gen; Mai, Kangsen; Zhou, Huihui; Xu, Wei; Song, Fei
2016-04-01
Turbot ( Scophthalmus maximus L.), a carnivorous fish species with high dietary protein requirement, was chosen to examine the expression pattern of peptide and amino acid transporter genes along its digestive tract which was divided into six segments including stomach, pyloric caeca, rectum, and three equal parts of the remainder of the intestine. The results showed that the expression of two peptide and eleven amino acid transporters genes exhibited distinct patterns. Peptide transporter 1 (PepT1) was rich in proximal intestine while peptide transporter 2 (PepT2) was abundant in distal intestine. A number of neutral and cationic amino acid transporters expressed richly in whole intestine including B0-type amino acid transporter 1 (B0AT1), L-type amino acid transporter 2 (LAT2), T-type amino acid transporter 1 (TAT1), proton-coupled amino acid transporter 1 (PAT1), y+L-type amino acid transporter 1 (y+LAT1), and cationic amino acid transporter 2 (CAT2) while ASC amino acid transporter 2 (ASCT2), sodium-coupled neutral amino acid transporter 2 (SNAT2), and y+L-type amino acid transporter 2 (y+LAT2) abundantly expressed in stomach. In addition, system b0,+ transporters (rBAT and b0,+AT) existed richly in distal intestine. These findings comprehensively characterized the distribution of solute carrier family proteins, which revealed the relative importance of peptide and amino acid absorption through luminal membrane. Our findings are helpful to understand the mechanism of the utilization of dietary protein in fish with a short digestive tract.
Hsu, Shu-Shong; Chou, Chiang-Ting; Liao, Wei-Chuan; Shieh, Pochuen; Kuo, Daih-Huang; Kuo, Chun-Chi; Jan, Chung-Ren; Liang, Wei-Zhe
2016-05-25
Gallic acid, a polyhydroxylphenolic compound, is widely distributed in various plants, fruits and foods. It has been shown that gallic acid passes into blood brain barrier and reaches the brain tissue of middle cerebral artery occlusion rats. However, the effect of gallic acid on Ca(2+) signaling in glia cells is unknown. This study explored whether gallic acid affected Ca(2+) homeostasis and induced Ca(2+)-associated cytotoxicity in DBTRG-05MG human glioblastoma cells and CTX TNA2 rat astrocytes. Gallic acid (20-40 μM) concentration-dependently induced cytotoxicity and intracellular Ca(2+) level ([Ca(2+)]i) increases in DBTRG-05MG cells but not in CTX TNA2 cells. In DBTRG-05MG cells, the Ca(2+) response was decreased by half by removal of extracellular Ca(2+). In Ca(2+)-containing medium, gallic acid-induced Ca(2+) entry was inhibited by store-operated Ca(2+) channel inhibitors (2-APB, econazole and SKF96365). In Ca(2+)-free medium, pretreatment with the endoplasmic reticulum Ca(2+) pump inhibitor thapsigargin abolished gallic acid-induced [Ca(2+)]i increases. Conversely, incubation with gallic acid also abolished thapsigargin-induced [Ca(2+)]i increases. Inhibition of phospholipase C with U73122 abolished gallic acid-induced [Ca(2+)]i increases. Gallic acid significantly caused cytotoxicity in DBTRG-05MG cells, which was partially prevented by prechelating cytosolic Ca(2+) with BAPTA-AM. Moreover, gallic acid activated mitochondrial apoptotic pathways that involved ROS production. Together, in DBTRG-05MG cells but not in CTX TNA2 cells, gallic acid induced [Ca(2+)]i increases by causing Ca(2+) entry via 2-APB, econazole and SKF96365-sensitive store-operated Ca(2+) entry, and phospholipase C-dependent release from the endoplasmic reticulum. This Ca(2+) signal subsequently evoked mitochondrial pathways of apoptosis that involved ROS production. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.
Avula, Satya Girish Chandra; Belovich, Joanne M; Xu, Yan
2017-05-01
Algae can synthesize, accumulate and store large amounts of lipids in its cells, which holds immense potential as a renewable source of biodiesel. In this work, we have developed and validated a GC-MS method for quantitation of fatty acids and glycerolipids in forms of fatty acid methyl esters derived from algae biomass. Algae Scenedesmus dimorphus dry mass was pulverized by mortar and pestle, then extracted by the modified Folch method and fractionated into free fatty acids and glycerolipids on aminopropyl solid-phase extraction cartridges. Fatty acid methyl esters were produced by an optimized one-step esterification of fatty acids and transesterification of glycerolipids with boron trichloride/methanol. The matrix effect, recoveries and stability of fatty acids and glycerolipids in algal matrix were first evaluated by spiking stable isotopes of pentadecanoic-2,2-d 2 acid and glyceryl tri(hexadecanoate-2,2-d 2 ) as surrogate analytes and tridecanoic-2,2-d 2 acid as internal standard into algal matrix prior to sample extraction. Later, the method was validated in terms of lower limits of quantitation, linear calibration ranges, intra- and inter-assay precision and accuracy using tridecanoic-2,2-d 2 acid as internal standard. The method developed has been applied to the quantitation of fatty acid methyl esters from free fatty acid and glycerolipid fractions of algae Scenedesmus dimorphus. © 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.
Pham, Anh-Tung; Shannon, J Grover; Bilyeu, Kristin D
2012-08-01
High oleic acid soybeans were produced by combining mutant FAD2-1A and FAD2-1B genes. Despite having a high oleic acid content, the linolenic acid content of these soybeans was in the range of 4-6 %, which may be high enough to cause oxidative instability of the oil. Therefore, a study was conducted to incorporate one or two mutant FAD3 genes into the high oleic acid background to further reduce the linolenic acid content. As a result, soybean lines with high oleic acid and low linolenic acid (HOLL) content were produced using different sources of mutant FAD2-1A genes. While oleic acid content of these HOLL lines was stable across two testing environments, the reduction of linolenic acid content varied depending on the number of mutant FAD3 genes combined with mutant FAD2-1 genes, on the severity of mutation in the FAD2-1A gene, and on the testing environment. Combination of two mutant FAD2-1 genes and one mutant FAD3 gene resulted in less than 2 % linolenic acid content in Portageville, Missouri (MO) while four mutant genes were needed to achieve the same linolenic acid in Columbia, MO. This study generated non-transgenic soybeans with the highest oleic acid content and lowest linolenic acid content reported to date, offering a unique alternative to produce a fatty acid profile similar to olive oil.
Studies on the oxidation of hexamethylbenzene 1: Oxidation of hexamethylbenzene with nitric acid
NASA Technical Reports Server (NTRS)
Chiba, K.; Tomura, S.; Mizuno, T.
1986-01-01
The oxidative reaction of hexamethylbenzene (HMB) with nitric acid was studied, and the hitherto unknown polymethylbenzenepolycarboxylic acids were isolated: tetramethylphthalic anhydride, tetramethylisophthalic acid, 1,3,5-, 1,2,4- and 1,2,3-trimethylbenzenetricarboxylic acids. When HMB was warmed with 50% nitric acid at about 80 C, tetramethylphthalic anhydride and tetramethylisophthalic acid were initially produced. The continued reaction led to the production of trimethylbenzenetricarboxylic acids, but only slight amounts of dimethylbenzenetetracarboxylic acids were detected in the reaction mixture. Whereas tetramethylphthalic anydride and tetramethylisophthalic acid were obtained, pentamethylbenzoic acid, a possible precursor of them, was scarcely produced. On the other hand, a yellow material extracted with ether from the initial reaction mixture contained bis-(nitromethyl)prehnitene (CH3)4C6(CH2NO2)2, which was easily converted into the phthalic anhydride.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Gilkey, Matthew J.; Balakumar, Rachana; Vlachos, Dionisios G.
We recently reported biomass-derived tetrahydrofuran-2,5-dicarboxylic acid (THFDCA) as a potential renewable feedstock for adipic acid (AA) production by combining HI and molecular H 2 in organic acid solvents.
Gilkey, Matthew J.; Balakumar, Rachana; Vlachos, Dionisios G.; ...
2018-01-01
We recently reported biomass-derived tetrahydrofuran-2,5-dicarboxylic acid (THFDCA) as a potential renewable feedstock for adipic acid (AA) production by combining HI and molecular H 2 in organic acid solvents.
ω-Oxidation of α-Chlorinated Fatty Acids
Brahmbhatt, Viral V.; Albert, Carolyn J.; Anbukumar, Dhanalakshmi S.; Cunningham, Bryce A.; Neumann, William L.; Ford, David A.
2010-01-01
Myeloperoxidase-derived HOCl targets tissue- and lipoprotein-associated plasmalogens to generate α-chlorinated fatty aldehydes, including 2-chlorohexadecanal. Under physiological conditions, 2-chlorohexadecanal is oxidized to 2-chlorohexadecanoic acid (2-ClHA). This study demonstrates the catabolism of 2-ClHA by ω-oxidation and subsequent β-oxidation from the ω-end. Mass spectrometric analyses revealed that 2-ClHA is ω-oxidized in the presence of liver microsomes with initial ω-hydroxylation of 2-ClHA. Subsequent oxidation steps were examined in a human hepatocellular cell line (HepG2). Three different α-chlorinated dicarboxylic acids, 2-chlorohexadecane-(1,16)-dioic acid, 2-chlorotetradecane-(1,14)-dioic acid, and 2-chloroadipic acid (2-ClAdA), were identified. Levels of 2-chlorohexadecane-(1,16)-dioic acid, 2-chlorotetradecane-(1,14)-dioic acid, and 2-ClAdA produced by HepG2 cells were dependent on the concentration of 2-ClHA and the incubation time. Synthetic stable isotope-labeled 2-ClHA was used to demonstrate a precursor-product relationship between 2-ClHA and the α-chlorinated dicarboxylic acids. We also report the identification of endogenous 2-ClAdA in human and rat urine and elevations in stable isotope-labeled urinary 2-ClAdA in rats subjected to intraperitoneal administration of stable isotope-labeled 2-ClHA. Furthermore, urinary 2-ClAdA and plasma 2-ClHA levels are increased in LPS-treated rats. Taken together, these data show that 2-ClHA is ω-oxidized to generate α-chlorinated dicarboxylic acids, which include α-chloroadipic acid that is excreted in the urine. PMID:20956542
The suppression of the N-nitrosating reaction by chlorogenic acid.
Kono, Y; Shibata, H; Kodama, Y; Sawa, Y
1995-01-01
N-Nitrosation of a model aromatic amine (2,3-diamino-naphthalene) by the N-nitrosating agent produced by nitrite in acidic solution was inhibited by a polyphenol, chlorogenic acid, which is an ester of caffeic acid quinic acid. Caffeic acid also inhibited the N-nitrosation, but quinic acid did not. 1,2-Benzenediols and 3,4-dihydroxybenzoic acid had inhibitory activities. Chlorogenic acid, caffeic acid, 1,2-benzenediols and 3,4-dihydroxybenzoic acid were able to scavenge the stable free radical, 1,1-diphenyl-2-picrylhydrazyl. Chlorogenic acid was found to be nitrated by acidic nitrite. The kinetic studies and the nitration observed only by bubbling of nitric oxide plus nitrogen dioxide gases indicated that the nitrating agent was nitrogen sesquioxide. The observations showed that the mechanism by which chlorogenic acid inhibited N-nitrosation of 2,3-diamino-naphthalene is due to its ability to scavenge the nitrosating agent, nitrogen sesquioxide. Chlorogenic acid may be effective not only in protecting against oxidative damage but also in inhibiting potentially mutagenic and carcinogenic reactions in vivo. PMID:8554543
Detailed mechanistic investigation into the S-nitrosation of cysteamine.
Morakinyo, Moshood K; Chipinda, Itai; Hettick, Justin; Siegel, Paul D; Abramson, Jonathan; Strongin, Robert; Martincigh, Bice S; Simoyi, Reuben H
The nitrosation of cysteamine (H 2 NCH 2 CH 2 SH) to produce cysteamine- S -nitrosothiol (CANO) was studied in slightly acidic medium by using nitrous acid prepared in situ. The stoichiometry of the reaction was H 2 NCH 2 CH 2 SH + HNO 2 → H 2 NCH 2 CH 2 SNO + H 2 O. On prolonged standing, the nitrosothiol decomposed quantitatively to yield the disulfide, cystamine: 2H 2 NCH 2 CH 2 SNO → H 2 NCH 2 CH 2 S-SCH 2 CH 2 NH 2 + 2NO. NO 2 and N 2 O 3 are not the primary nitrosating agents, since their precursor (NO) was not detected during the nitrosation process. The reaction is first order in nitrous acid, thus implicating it as the major nitrosating agent in mildly acidic pH conditions. Acid catalyzes nitrosation after nitrous acid has saturated, implicating the protonated nitrous acid species, the nitrosonium cation (NO + ) as a contributing nitrosating species in highly acidic environments. The acid catalysis at constant nitrous acid concentrations suggests that the nitrosonium cation nitrosates at a much higher rate than nitrous acid. Bimolecular rate constants for the nitrosation of cysteamine by nitrous acid and by the nitrosonium cation were deduced to be 17.9 ± 1.5 (mol/L) -1 s -1 and 6.7 × 10 4 (mol/L) -1 s -1 , respectively. Both Cu(I) and Cu(II) ions were effective catalysts for the formation and decomposition of the cysteamine nitrosothiol. Cu(II) ions could catalyze the nitrosation of cysteamine in neutral conditions, whereas Cu(I) could only catalyze in acidic conditions. Transnitrosation kinetics of CANO with glutathione showed the formation of cystamine and the mixed disulfide with no formation of oxidized glutathione (GSSG). The nitrosation reaction was satisfactorily simulated by a simple reaction scheme involving eight reactions.
Detailed mechanistic investigation into the S-nitrosation of cysteamine
Morakinyo, Moshood K.; Chipinda, Itai; Hettick, Justin; Siegel, Paul D.; Abramson, Jonathan; Strongin, Robert; Martincigh, Bice S.; Simoyi, Reuben H.
2015-01-01
The nitrosation of cysteamine (H2NCH2CH2SH) to produce cysteamine-S-nitrosothiol (CANO) was studied in slightly acidic medium by using nitrous acid prepared in situ. The stoichiometry of the reaction was H2NCH2CH2SH + HNO2 → H2NCH2CH2SNO + H2O. On prolonged standing, the nitrosothiol decomposed quantitatively to yield the disulfide, cystamine: 2H2NCH2CH2SNO → H2NCH2CH2S–SCH2CH2NH2 + 2NO. NO2 and N2O3 are not the primary nitrosating agents, since their precursor (NO) was not detected during the nitrosation process. The reaction is first order in nitrous acid, thus implicating it as the major nitrosating agent in mildly acidic pH conditions. Acid catalyzes nitrosation after nitrous acid has saturated, implicating the protonated nitrous acid species, the nitrosonium cation (NO+) as a contributing nitrosating species in highly acidic environments. The acid catalysis at constant nitrous acid concentrations suggests that the nitrosonium cation nitrosates at a much higher rate than nitrous acid. Bimolecular rate constants for the nitrosation of cysteamine by nitrous acid and by the nitrosonium cation were deduced to be 17.9 ± 1.5 (mol/L)−1 s−1 and 6.7 × 104 (mol/L)−1 s−1, respectively. Both Cu(I) and Cu(II) ions were effective catalysts for the formation and decomposition of the cysteamine nitrosothiol. Cu(II) ions could catalyze the nitrosation of cysteamine in neutral conditions, whereas Cu(I) could only catalyze in acidic conditions. Transnitrosation kinetics of CANO with glutathione showed the formation of cystamine and the mixed disulfide with no formation of oxidized glutathione (GSSG). The nitrosation reaction was satisfactorily simulated by a simple reaction scheme involving eight reactions. PMID:26594054
Triterpenoids from the roots of Rubus parvifolius.
Zhang, Xu; Zhu, Zhi-Xiang; Wang, Juan; Yang, Wan-Qing; Su, Cong; Li, Jun; Zhang, Yuan; Zheng, Jiao; Shi, She-Po; Tu, Peng-Fei
2016-05-01
Two new oleanane-type triterpenoids, parvifolactone A (1) and rubuside P (2), together with 11 known triterpenoids, fupenzic acid (3), 18,19-seco,2α,3α-dihydroxyl-19-oxo-urs-11,13(18)-dien-28-oic acid (4), euscaphic acid (5), maslinic acid (6), 1β- hydroxyeuscaphic acid (7), 2α,3α,19α,23-tetrahydroxyolean-12-en-28-oic acid (8), 2α,3β,19α,23-tetrahydroxyurs-12-en-28-oic acid (9), glucosyl pinfaensate (10), rubuside J (11), 2α,3α,19α,23-tetrahydroxyurs-12-en-24,28-dioic acid (12), and 2α,3β,19α- trihydroxyurs-12-en-23,28-dioic acid (13), were isolated from the roots of Rubus parvifolius. Copyright © 2016 China Pharmaceutical University. Published by Elsevier B.V. All rights reserved.
NASA Astrophysics Data System (ADS)
Treadaway, Victoria; Heikes, Brian G.; McNeill, Ashley S.; Silwal, Indira K. C.; O'Sullivan, Daniel W.
2018-04-01
A chemical ionization mass spectrometry (CIMS) method utilizing a reagent gas mixture of O2, CO2, and CH3I in N2 is described and optimized for quantitative gas-phase measurements of hydrogen peroxide (H2O2), methyl peroxide (CH3OOH), formic acid (HCOOH), and the sum of acetic acid (CH3COOH) and hydroxyacetaldehyde (HOCH2CHO; also known as glycolaldehyde). The instrumentation and methodology were designed for airborne in situ field measurements. The CIMS quantification of formic acid, acetic acid, and hydroxyacetaldehyde used I- cluster formation to produce and detect the ion clusters I-(HCOOH), I-(CH3COOH), and I-(HOCH2CHO), respectively. The CIMS also produced and detected I- clusters with hydrogen peroxide and methyl peroxide, I-(H2O2) and I-(CH3OOH), though the sensitivity was lower than with the O2- (CO2) and O2- ion clusters, respectively. For that reason, while the I- peroxide clusters are presented, the focus is on the organic acids. Acetic acid and hydroxyacetaldehyde were found to yield equivalent CIMS responses. They are exact isobaric compounds and indistinguishable in the CIMS used. Consequently, their combined signal is referred to as the acetic acid equivalent sum
. Within the resolution of the quadrupole used in the CIMS (1 m/z), ethanol and 1- and 2-propanol were potential isobaric interferences to the measurement of formic acid and the acetic acid equivalent sum, respectively. The CIMS response to ethanol was 3.3 % that of formic acid and the response to either 1- or 2-propanol was 1 % of the acetic acid response; therefore, the alcohols were not considered to be significant interferences to formic acid or the acetic acid equivalent sum. The multi-reagent ion system was successfully deployed during the Front Range Air Pollution and Photochemistry Éxperiment (FRAPPÉ) in 2014. The combination of FRAPPÉ and laboratory calibrations allowed for the post-mission quantification of formic acid and the acetic acid equivalent sum observed during the Deep Convective Clouds and Chemistry Experiment in 2012.
Roser, Kurt S.; Brookes, Paul S.; Wojtovich, Andrew P.; Olson, Leif P.; Shojaie, Jalil; Parton, Richard L.; Anders, M. W.
2010-01-01
Mitochondrial reactive oxygen species (ROS) generation and the attendant mitochondrial dysfunction are implicated in a range of disease states. The objective of the present studies was to test the hypothesis that the mitochondrial β-oxidation pathway could be exploited to deliver and biotransform the prodrugs ω-(phenoxy)alkanoic acids, 3-(phenoxy)acrylic acids, and ω-(1-methyl-1H-imidazol-2-ylthio)alkanoic acids to the corresponding phenolic antioxidants or methimazole. 3 -and 5-(Phenoxy)alkanoic acids and methyl-substituted analogs were biotransformed to phenols; rates of biotransformation decreased markedly with methyl-group substitution on the phenoxy moiety. 2,6-Dimethylphenol formation from the analogs 3-([2,6-dimethylphenoxy]methylthio)propanoic acid and 3-(2,6-dimethylphenoxy)acrylic acid was greater than that observed with ω-(2,6-dimethylphenoxy)alkanoic acids. 3- and 5-(1-Methyl-1H-imidazol-2-ylthio)alkanoic acids were rapidly biotransformed to the antioxidant methimazole and conferred significant cytoprotection against hypoxia-reoxygenation injury in isolated cardiomyocytes. Both 3-(2,6-dimethylphenoxy)propanoic acid and 3-(2,6-dimethylphenoxy)acrylic acid also afforded cytoprotection against hypoxia-reoxygenation injury in isolated cardiomyocytes. These results demonstrate that mitochondrial β-oxidation is a potentially useful delivery system for targeting antioxidants to mitochondria. PMID:20129794
2013-12-01
degradation 2 Pipecolic acid II 2-keto-6- aminocaproate II Pyruvate metabolism 1 Malic acid I Purine metabolism 1 Guanine I Propanoate metabolism 1...acetamidobutanoic acid II cis-4-hydroxy-D-proline II D-arginine and D-ornithine metabolism 4 Ornithine II 5-amino-2-oxopentanoic acid II 2-amino-4-oxo...pentanoic acid II (2R,4S)-2,4-diaminopentanoate II Gly, Ser, and Thr metabolism 3 L-cystathionine II Choline II 5-aminolevulinic acid II Val
Meier, Anna K.; Worch, Sebastian; Böer, Erik; Hartmann, Anja; Mascher, Martin; Marzec, Marek; Scholz, Uwe; Riechen, Jan; Baronian, Kim; Schauer, Frieder; Bode, Rüdiger; Kunze, Gotthard
2017-01-01
Tannins and hydroxylated aromatic acids, such as gallic acid (3,4,5-trihydroxybenzoic acid), are plant secondary metabolites which protect plants against herbivores and plant-associated microorganisms. Some microbes, such as the yeast Arxula adeninivorans are resistant to these antimicrobial substances and are able to use tannins and gallic acid as carbon sources. In this study, the Arxula gallic acid decarboxylase (Agdc1p) which degrades gallic acid to pyrogallol was characterized and its function in tannin catabolism analyzed. The enzyme has a higher affinity for gallic acid (Km −0.7 ± 0.2 mM, kcat −42.0 ± 8.2 s−1) than to protocatechuic acid (3,4-dihydroxybenzoic acid) (Km −3.2 ± 0.2 mM, kcat −44.0 ± 3.2 s−1). Other hydroxylated aromatic acids, such as 3-hydroxybenzoic acid, 4-hydroxybenzoic acid, 2,3-dihydroxybenzoic acid, 2,4-dihydroxybenzoic acid and 2,5-dihydroxybenzoic acid are not gallic acid decarboxylase substrates. A. adeninivorans G1212/YRC102-AYNI1-AGDC1, which expresses the AGDC1 gene under the control of the strong nitrate inducible AYNI1 promoter achieved a maximum gallic acid decarboxylase activity of 1064.4 U/l and 97.5 U/g of dry cell weight in yeast grown in minimal medium with nitrate as nitrogen source and glucose as carbon source. In the same medium, gallic acid decarboxylase activity was not detected for the control strain G1212/YRC102 with AGDC1 expression under the control of the endogenous promoter. Gene expression analysis showed that AGDC1 is induced by gallic acid and protocatechuic acid. In contrast to G1212/YRC102-AYNI1-AGDC1 and G1212/YRC102, A. adeninivorans G1234 [Δagdc1] is not able to grow on medium with gallic acid as carbon source but can grow in presence of protocatechuic acid. This confirms that Agdc1p plays an essential role in the tannic acid catabolism and could be useful in the production of catechol and cis,cis-muconic acid. However, the protocatechuic acid catabolism via Agdc1p to catechol seems to be not the only degradation pathway. PMID:28966611
Meier, Anna K; Worch, Sebastian; Böer, Erik; Hartmann, Anja; Mascher, Martin; Marzec, Marek; Scholz, Uwe; Riechen, Jan; Baronian, Kim; Schauer, Frieder; Bode, Rüdiger; Kunze, Gotthard
2017-01-01
Tannins and hydroxylated aromatic acids, such as gallic acid (3,4,5-trihydroxybenzoic acid), are plant secondary metabolites which protect plants against herbivores and plant-associated microorganisms. Some microbes, such as the yeast Arxula adeninivorans are resistant to these antimicrobial substances and are able to use tannins and gallic acid as carbon sources. In this study, the Arxula gallic acid decarboxylase (Agdc1p) which degrades gallic acid to pyrogallol was characterized and its function in tannin catabolism analyzed. The enzyme has a higher affinity for gallic acid (K m -0.7 ± 0.2 mM, k cat -42.0 ± 8.2 s -1 ) than to protocatechuic acid (3,4-dihydroxybenzoic acid) (K m -3.2 ± 0.2 mM, k cat -44.0 ± 3.2 s -1 ). Other hydroxylated aromatic acids, such as 3-hydroxybenzoic acid, 4-hydroxybenzoic acid, 2,3-dihydroxybenzoic acid, 2,4-dihydroxybenzoic acid and 2,5-dihydroxybenzoic acid are not gallic acid decarboxylase substrates. A. adeninivorans G1212/YRC102-AYNI1-AGDC1, which expresses the AGDC1 gene under the control of the strong nitrate inducible AYNI1 promoter achieved a maximum gallic acid decarboxylase activity of 1064.4 U/l and 97.5 U/g of dry cell weight in yeast grown in minimal medium with nitrate as nitrogen source and glucose as carbon source. In the same medium, gallic acid decarboxylase activity was not detected for the control strain G1212/YRC102 with AGDC1 expression under the control of the endogenous promoter. Gene expression analysis showed that AGDC1 is induced by gallic acid and protocatechuic acid. In contrast to G1212/YRC102-AYNI1-AGDC1 and G1212/YRC102, A. adeninivorans G1234 [Δ agdc1 ] is not able to grow on medium with gallic acid as carbon source but can grow in presence of protocatechuic acid. This confirms that Agdc1p plays an essential role in the tannic acid catabolism and could be useful in the production of catechol and cis,cis -muconic acid. However, the protocatechuic acid catabolism via Agdc1p to catechol seems to be not the only degradation pathway.
Thermometric titration of acids in pyridine.
Vidal, R; Mukherjee, L M
1974-04-01
Thermometric titration of HClO(4), HI, HNO(3), HBr, picric acid o-nitrobenzoic acid, 2,4- and 2,5-dinitrophenol, acetic acid and benzoic acid have been attempted in pyridine as solvent, using 1,3-diphenylguanidine as the base. Except in the case of 2,5-dinitrophenol, acetic acid and benzoic acid, the results are, in general, reasonably satisfactory. The approximate molar heats of neutralization have been calculated.
Catabolism of Naphthalenesulfonic Acids by Pseudomonas sp. A3 and Pseudomonas sp. C22
Brilon, C.; Beckmann, W.; Knackmuss, H.-J.
1981-01-01
Naphthalene and two naphthalenesulfonic acids were degraded by Pseudomonas sp. A3 and Pseudomonas sp. C22 by the same enzymes. Gentisate is a major metabolite. Catabolic activities for naphthalene, 1-naphthalenesulfonic acid, and 2-naphthalenesulfonic acid are induced by growth with naphthalene, 1-naphthalenesulfonic acid, 2-naphthalenesulfonic acid, methylnaphthalene, or salicylate. Gentisate is also an inducer in strain A3. Inhibition kinetics show that naphthalene and substituted naphthalenes are hydroxylated by the same naphthalene dioxygenase. Substrates with nondissociable substituents such as CH3, OCH3, Cl, or NO2 are hydroxylated in the 7,8-position, and 4-substituted salicylates are accumulated. If CO2H, CH2CO2H, or SO3H are substituents, hydroxylation occurs with high regioselectivity in the 1,2-position. Thus, 1,2-dihydroxy-1,2-dihydronaphthalene-2-carboxylic acids are formed quantitatively from the corresponding naphthalenecarboxylic acids. Utilization of naphthalenesulfonic acids proceeds by the same regioselective 1,2-dioxygenation which labilizes the C—SO3− bond and eliminates sulfite. PMID:16345814
Hanzawa, Yohko; Hashimoto, Kahoko; Kasashima, Yoshio; Takahashi, Yoshiko; Mino, Takashi; Sakamoto, Masami; Fujita, Tsutomu
2012-01-01
3-hydroxy acids, 3-hydroxy-3,7-dimethyloct-6-enoic acid (1) and 3-hydroxy-2,2,3,7-tetramethyloct-6-enoic acid (2), were prepared from 6-methyl-5-hepten-2-one, and they were subsequently used to prepare (2,6,6-trimethyltetrahydropyran-2-yl)acetic acid (3) and 2-methyl-2-(2,6,6-trimethyltetrahydropyran-2-yl)propanoic acid (4), respectively, via cyclization with an acidic catalyst such as boron trifluoride diethyl etherate or iodine. The reaction of carboxylic acids 3 and 4 with alcohols, including methanol, ethanol, and 1-propanol, produced the corresponding methyl, ethyl, and propyl esters, which all contained a tetrahydropyran ring. Reduction of carboxylic acids 3 and 4 afforded the corresponding alcohols. Subsequent reactions of these alcohols with several acyl chlorides produced novel esters. The alcohols also reacted with methyl iodide and sodium hydride to provide novel ethers. A one-pot cyclization-esterification of 1 to produce esters containing a tetrahydropyran ring, using iodine as a catalyst, was also investigated.
NASA Astrophysics Data System (ADS)
Selvakumar, Rajendran; Geib, Steven J.; Muthu Sankar, Aathi; Premkumar, Thathan; Govindarajan, Subbaiah
2015-11-01
The reaction of aminoguanidine bicarbonate (Amg) with oxamic, oxalic, malonic and sulfoacetic acids yielded (AmgH)H2NOC-COO (1), OOC-CONHNHC(NH2)NH2 (2) (AmgH)HOOC-CH2-COO (3) and O3S-CH2-CONHNHC(NH2)NH2 (4), respectively. For the first time, we studied the salt-forming ability of aminoguanidine with several carboxylic acids, such as oxamic, oxalic, malonic and sulphoacetic acids. We also compared the structural and thermal properties of these salts. Oxamic and malonic acids form only mono-aminoguanidinium salts, whereas oxalic acid mainly forms di-aminoguanidinium oxalate. In addition, oxalic acid forms guanylhydrazido-oxalic acid which exists as zwitter ion. Unlike other acids, sulfoacetic acid readily forms only the zwitter ionic salts (2-guanylhydrazido-oxo-methanesulfonic acid) rather than the usual simple salt. This result may be a result of the highly acidic nature of the sulfonic group, which favors acid catalyzed condensation. More significantly, for the first time, the ability guanylhydrazido-oxalic acid (2) and 2-guanylhydrazido-oxo-methanesulfonic acid (4) to inhibit human butyrylcholinesterase (human BChE) receptor has been studied with a molecular docking approach. The binding of the compounds to human BChE was examined as it is crucial to understanding the biological significance of aminoguanidine derivatives. The compounds were identified and characterized by analytical, FT-IR spectroscopic and thermal studies. Furthermore, the structures of compounds 1, 2 and 4 were confirmed by single X-ray diffraction studies. Compounds 1 and 2 crystallized in a monoclinic crystal system with P21/c and Cc space groups, respectively, whereas compound 4 crystalized in an orthorhombic system with a Pbca space group. All the compounds (1-4) underwent endo- followed by exothermic decomposition in the temperature range from 130 to 600 °C to yield gaseous products.
Occurrence and metabolism of 7-hydroxy-2-indolinone-3-acetic acid in Zea mays
NASA Technical Reports Server (NTRS)
Lewer, P.; Bandurski, R. S.
1987-01-01
7-Hydroxy-2-indolinone-3-acetic acid was identified as a catabolite of indole-3-acetic acid in germinating kernels of Zea mays and found to be present in amounts of ca 3.1 nmol/kernel. 7-Hydroxy-2-indolinone-3-acetic acid was shown to be a biosynthetic intermediate between 2-indolinone-3-acetic acid and 7-hydroxy-2-indolinone-3-acetic acid-7'-O-glucoside in both kernels and roots of Zea mays. Further metabolism of 7-hydroxy-2-[5-3H]-indolinone-3-acetic acid-7'-O-glucoside occurred to yield tritiated water plus, as yet, uncharacterized products.
López-López, A; López-Sabater, M C; Campoy-Folgoso, C; Rivero-Urgell, M; Castellote-Bargalló, A I
2002-12-01
To investigate differences in fatty acid and sn-2 fatty acid composition in colostrum, transitional and mature human milk, and in term infant formulas. Departament de Nutrició i Bromatologia, University of Barcelona, Spain and University Hospital of Granada, Spain. One-hundred and twenty mothers and 11 available types of infant formulas for term infants. We analysed the fatty acid composition of colostrum (n=40), transitional milk (n=40), mature milk (n=40) and 11 infant formulas. We also analysed the fatty acid composition at sn-2 position in colostrum (n=12), transitional milk (n=12), mature milk (n=12), and the 11 infant formulas. Human milk in Spain had low saturated fatty acids, high monounsaturated fatty acids and high linolenic acid. Infant formulas and mature human milk had similar fatty acid composition. In mature milk, palmitic acid was preferentially esterified at the sn-2 position (86.25%), and oleic and linoleic acids were predominantly esterified at the sn-1,3 positions (12.22 and 22.27%, respectively, in the sn-2 position). In infant formulas, palmitic acid was preferentially esterified at the sn-1,3 positions and oleic and linoleic acids had higher percentages at the sn-2 position than they do in human milk. Fatty acid composition of human milk in Spain seems to reflect the Mediterranean dietary habits of mothers. Infant formulas resemble the fatty acid profile of human milk, but the distribution of fatty acids at the sn-2 position is markedly different.
Code of Federal Regulations, 2010 CFR
2010-07-01
... 40 Protection of Environment 30 2010-07-01 2010-07-01 false Hexanoic acid, 2-ethyl-, mixed... SUBSTANCES Significant New Uses for Specific Chemical Substances § 721.10109 Hexanoic acid, 2-ethyl-, mixed... to reporting. (1) The chemical substance identified as hexanoic acid, 2-ethyl-, mixed triesters with...
Code of Federal Regulations, 2012 CFR
2012-07-01
... 40 Protection of Environment 32 2012-07-01 2012-07-01 false Hexanoic acid, 2-ethyl-, mixed... SUBSTANCES Significant New Uses for Specific Chemical Substances § 721.10109 Hexanoic acid, 2-ethyl-, mixed... to reporting. (1) The chemical substance identified as hexanoic acid, 2-ethyl-, mixed triesters with...
Code of Federal Regulations, 2011 CFR
2011-07-01
... 40 Protection of Environment 31 2011-07-01 2011-07-01 false Hexanoic acid, 2-ethyl-, mixed... SUBSTANCES Significant New Uses for Specific Chemical Substances § 721.10109 Hexanoic acid, 2-ethyl-, mixed... to reporting. (1) The chemical substance identified as hexanoic acid, 2-ethyl-, mixed triesters with...
Code of Federal Regulations, 2013 CFR
2013-07-01
... 40 Protection of Environment 32 2013-07-01 2013-07-01 false Hexanoic acid, 2-ethyl-, mixed... SUBSTANCES Significant New Uses for Specific Chemical Substances § 721.10109 Hexanoic acid, 2-ethyl-, mixed... to reporting. (1) The chemical substance identified as hexanoic acid, 2-ethyl-, mixed triesters with...
Code of Federal Regulations, 2014 CFR
2014-07-01
... 40 Protection of Environment 31 2014-07-01 2014-07-01 false Hexanoic acid, 2-ethyl-, mixed... SUBSTANCES Significant New Uses for Specific Chemical Substances § 721.10109 Hexanoic acid, 2-ethyl-, mixed... to reporting. (1) The chemical substance identified as hexanoic acid, 2-ethyl-, mixed triesters with...
Metabolism of valine and 3-methyl-2-oxobutanoate by the isolated perfused rat kidney.
Miller, R H; Harper, A E
1984-01-01
Metabolism of branched-chain amino and 2-oxo acids was studied in the isolated perfused kidney. Significant amounts of 2-oxo acids were released by perfused kidney with all concentrations of amino acids tested (0.1-1.0 mM each), despite the high activity of branched-chain 2-oxo acid dehydrogenase in kidney. As perfusate valine concentration was increased from 0.2 to 1.0 mM, [1-14C]valine transamination (2-oxo acid oxidized + released) increased roughly linearly; [1-14C]valine oxidation, however, increased exponentially. Increasing perfusate concentration of 3-methyl-2-oxo[1-14C]butanoate from 0 to 1.0 mM resulted in a linear increase in the rate of its oxidation and a rise in perfusate valine concentration; at the same time significant decreases occurred in perfusate isoleucine and leucine concentrations, with corresponding increases in rates of release of their respective 2-oxo acids. Comparison of rates of oxidation of [1-14C]valine and 3-methyl-2-oxo[1-14C]butanoate suggests that 2-oxo acid arising from [1-14C]valine transamination has freer access to the 2-oxo acid dehydrogenase than has the 2-oxo acid from the perfusate. The observations indicate that, when branched-chain amino and 2-oxo acids are present in perfusate at near-physiological concentrations, rates of transamination of the amino and 2-oxo acids by isolated perfused kidney are greater than rates of oxidation. PMID:6508752
Acetylcholinesterase inhibitory properties of some benzoic acid derivatives
NASA Astrophysics Data System (ADS)
Yildiz, Melike; Kiliç, Deryanur; Ünver, Yaǧmur; Şentürk, Murat; Askin, Hakan; Küfrevioǧlu, Ömer Irfan
2016-04-01
Acetylcholinesterase (AChE) hydrolyses the neurotransmitter acetylcholine to acetic acid and choline. AChE inhibitors are used in treatment of several neurodegeneartive disorder and Alzheimer's disease. In the present study, inhibition of AChE with some benzoic acid derivatives were investigated. 3-Chloro-benzoic acid (1), 2-hydroxy-5-sulfobenzoic acid (2), 2-(sulfooxy) benzoic acid (3), 2-hydroxybenzoic acid (4), 2,3-dimethoxybenzoic (5), and 3,4,5-trimethoxybenzoic (6) were calculated IC50 values AChE enzyme. Kinetic investigations showed that similarly to AChE inhibitors. Benzoic acid derivatives (1-6) investigated are encouraging agents which may be used as lead molecules in order to derivative novel AChE inhibitors that might be useful in medical applications.
Code of Federal Regulations, 2014 CFR
2014-07-01
... 40 Protection of Environment 31 2014-07-01 2014-07-01 false Phosphonic acid, P-[2-[bis(2... SUBSTANCES Significant New Uses for Specific Chemical Substances § 721.10243 Phosphonic acid, P-[2-[bis(2... to reporting. (1) The chemical substance identified as phosphonic acid, P-[2-[bis(2-hydroxyethyl...
Code of Federal Regulations, 2013 CFR
2013-07-01
... 40 Protection of Environment 32 2013-07-01 2013-07-01 false Phosphonic acid, P-[2-[bis(2... SUBSTANCES Significant New Uses for Specific Chemical Substances § 721.10243 Phosphonic acid, P-[2-[bis(2... to reporting. (1) The chemical substance identified as phosphonic acid, P-[2-[bis(2-hydroxyethyl...
Foliar Fatty Acids and Sterols of Soybean Field Fumigated with SO2
Grunwald, Claus
1981-01-01
Sixty-day-old soybean plants were exposed in the field to 78.7 parts per one-hundred million of SO2 in an open-air fumigation system for 20 days. Leaves from the top one-fourth and bottom one-fourth of the plants were analyzed for chlorophyll, free fatty acids, fatty acid esters, polar lipid fatty acids, and sterols. Fumigated plants had a lower chlorophyll, free fatty acid, and polar lipid content, but a higher fatty acid ester content. Of the individual fatty acids, linoleic and linolenic acid increased with SO2 fumigation while palmitic acid decreased. SO2 fumigations had only a minor effect on leaf sterols. In general, the lower, more mature leaves showed a greater response to SO2 exposure. PMID:16662015
Demorest, Zachary L; Coffman, Andrew; Baltes, Nicholas J; Stoddard, Thomas J; Clasen, Benjamin M; Luo, Song; Retterath, Adam; Yabandith, Ann; Gamo, Maria Elena; Bissen, Jeff; Mathis, Luc; Voytas, Daniel F; Zhang, Feng
2016-10-13
The ability to modulate levels of individual fatty acids within soybean oil has potential to increase shelf-life and frying stability and to improve nutritional characteristics. Commodity soybean oil contains high levels of polyunsaturated linoleic and linolenic acid, which contribute to oxidative instability - a problem that has been addressed through partial hydrogenation. However, partial hydrogenation increases levels of trans-fatty acids, which have been associated with cardiovascular disease. Previously, we generated soybean lines with knockout mutations within fatty acid desaturase 2-1A (FAD2-1A) and FAD2-1B genes, resulting in oil with increased levels of monounsaturated oleic acid (18:1) and decreased levels of linoleic (18:2) and linolenic acid (18:3). Here, we stack mutations within FAD2-1A and FAD2-1B with mutations in fatty acid desaturase 3A (FAD3A) to further decrease levels of linolenic acid. Mutations were introduced into FAD3A by directly delivering TALENs into fad2-1a fad2-1b soybean plants. Oil from fad2-1a fad2-1b fad3a plants had significantly lower levels of linolenic acid (2.5 %), as compared to fad2-1a fad2-1b plants (4.7 %). Furthermore, oil had significantly lower levels of linoleic acid (2.7 % compared to 5.1 %) and significantly higher levels of oleic acid (82.2 % compared to 77.5 %). Transgene-free fad2-1a fad2-1b fad3a soybean lines were identified. The methods presented here provide an efficient means for using sequence-specific nucleases to stack quality traits in soybean. The resulting product comprised oleic acid levels above 80 % and linoleic and linolenic acid levels below 3 %.
Properties of the branched-chain 2-hydroxy acid/2-oxo acid shuttle in mouse spermatozoa.
Coronel, C E; Gallina, F G; Gerez de Burgos, N M; Burgos, C; Blanco, A
1986-05-01
Operation of the branched-chain 2-hydroxy acid/2-oxo acid shuttle for the transfer of reducing equivalents in mitochondria of mouse spermatozoa was studied in vitro in reconstituted systems. Results show that the branched-chain 2-oxo acids within the mitochondria are offered several metabolic pathways. (a) Decarboxylation: mouse sperm mitochondria possess high branched-chain 2-oxo acid decarboxylase activity. (b) Recycling to the cytosol by using a transport system which can be inhibited by alpha-cyano-3-hydroxycinnamate and pH 6.8. (c) Transamination to the corresponding amino acids: experiments presented indicate that leucine formed from 4-methyl-2-oxopentanoate may pass to the external phase, re-initiating the cycle. These two last possibilities would allow autocatalytic operation of the shuttle. The branched-chain 2-hydroxy acids apparently do not utilize the monocarboxylate carrier to penetrate the mitochondria.
40 CFR 721.10140 - Phosphoric acid, tin (2+) salt (2:3).
Code of Federal Regulations, 2010 CFR
2010-07-01
... 40 Protection of Environment 30 2010-07-01 2010-07-01 false Phosphoric acid, tin (2+) salt (2:3... Specific Chemical Substances § 721.10140 Phosphoric acid, tin (2+) salt (2:3). (a) Chemical substance and significant new uses subject to reporting. (1) The chemical substance identified as phosphoric acid, tin (2...
40 CFR 721.10140 - Phosphoric acid, tin (2+) salt (2:3).
Code of Federal Regulations, 2012 CFR
2012-07-01
... 40 Protection of Environment 32 2012-07-01 2012-07-01 false Phosphoric acid, tin (2+) salt (2:3... Specific Chemical Substances § 721.10140 Phosphoric acid, tin (2+) salt (2:3). (a) Chemical substance and significant new uses subject to reporting. (1) The chemical substance identified as phosphoric acid, tin (2...
40 CFR 721.10140 - Phosphoric acid, tin (2+) salt (2:3).
Code of Federal Regulations, 2013 CFR
2013-07-01
... 40 Protection of Environment 32 2013-07-01 2013-07-01 false Phosphoric acid, tin (2+) salt (2:3... Specific Chemical Substances § 721.10140 Phosphoric acid, tin (2+) salt (2:3). (a) Chemical substance and significant new uses subject to reporting. (1) The chemical substance identified as phosphoric acid, tin (2...
40 CFR 721.10140 - Phosphoric acid, tin (2+) salt (2:3).
Code of Federal Regulations, 2011 CFR
2011-07-01
... 40 Protection of Environment 31 2011-07-01 2011-07-01 false Phosphoric acid, tin (2+) salt (2:3... Specific Chemical Substances § 721.10140 Phosphoric acid, tin (2+) salt (2:3). (a) Chemical substance and significant new uses subject to reporting. (1) The chemical substance identified as phosphoric acid, tin (2...
40 CFR 721.10140 - Phosphoric acid, tin (2+) salt (2:3).
Code of Federal Regulations, 2014 CFR
2014-07-01
... 40 Protection of Environment 31 2014-07-01 2014-07-01 false Phosphoric acid, tin (2+) salt (2:3... Specific Chemical Substances § 721.10140 Phosphoric acid, tin (2+) salt (2:3). (a) Chemical substance and significant new uses subject to reporting. (1) The chemical substance identified as phosphoric acid, tin (2...
Varani, J.; Shayevitz, J.; Perry, D.; Mitra, R. S.; Nickoloff, B. J.; Voorhees, J. J.
1990-01-01
Human dermal fibroblasts failed to proliferate when cultured in medium containing 0.15 mmol/l (millimolar) Ca2+ (keratinocyte growth medium [KGM]) but did when the external Ca2+ concentration was raised to 1.4 mmol/l. All-trans retinoic acid (retinoic acid) stimulated proliferation in KGM but did not further stimulate growth in Ca2(+)-supplemented KGM. The ability of retinoic acid to stimulate proliferation was inhibited in KGM prepared without Ca2+ or prepared with 0.03 mmol/l Ca2+ and in KGM treated with 1 mmol/l ethylene-glycol-bis-(beta-aminoethyl ether)N,N'-tetra acetic acid. Using 45Ca2+ to measure Ca2+ influx and efflux, it was found that retinoic acid minimally increased Ca2+ uptake into fibroblasts. In contrast, retinoic acid treatment of fibroblasts that had been pre-equilibrated for 1 day with 45Ca2+ inhibited release of intracellular Ca2+ into the extracellular fluid. Retinoic acid also stimulated 35S-methionine incorporation into trichloroacetic acid-precipitable material but in contrast to its effect on proliferation, stimulation of 35S-methionine incorporation occurred in both high-Ca2+ and low-Ca2+ medium. These data indicate that retinoic acid stimulation of proliferation, but not protein synthesis, is dependent on the concentration of Ca2+ in the extracellular environment. PMID:2356860
Effect of Sulfuric Acid on the Uptake of Sulfur Dioxide on Soot
NASA Astrophysics Data System (ADS)
Slowik, J. G.; Koehler, B. G.
2001-05-01
The uptake of SO2 on soot may lead to the formation of sulfuric acid on the soot. The sulfuric acid then can affect the further uptake of SO2 on the soot. We are interested in the effect of submonolayer H2SO4 on the uptake of SO2. We measured the uptake of SO2 on n-hexane soot as a function SO2 pressure (10-7 to 10-4 Torr) and sulfuric acid coverage between -140\\deg and -120\\deg C. We generate sulfuric acid by adsorbing varying amounts of SO3 on soot, covering the SO3 with a thick layer of condensed H2O, and heating to 193 K to react the SO3 and H2O and to remove the excess H2O. The sulfuric acid coverage is in the range of monolayer or sub-monolayer. Adsorption of SO2 on soot with and without the sulfuric acid shows that the acid reduces the SO2 uptake by a factor of two or more. Varying the amount of acid has little effect on uptake. However, increasing the thickness of the soot substrate causes a significant increase in SO2 uptake.
Tsai, Chin-Shaw Stella; Luo, Shue-Fen; Ning, Chung-Chu; Lin, Chien-Liang; Jiang, Ming-Chung; Liao, Ching-Fong
2009-08-01
Epidemiological studies indicate that acetylsalicylic acid may reduce the risk of mortality due to colon cancers. Metastasis is the major cause of cancer death. Matrix metalloproteinases (MMPs) play important roles in tumor invasion regulation, and prostaglandin F(2)alpha (PGF(2)alpha) is a key stimulator of MMP production. Thus, we investigated whether acetylsalicylic acid regulated MMP activity and the invasion of cancer cells and whether PGF(2)alpha attenuated acetylsalicylic acid-inhibited invasion of cancer cells. Gelatin-based zymography assays showed that acetylsalicylic acid inhibited the MMP-2 activity of B16F0 melanoma cells. Matrigel-based chemoinvasion assays showed that acetylsalicylic acid inhibited the invasion of B16F0 cells. Acetylsalicylic acid can inhibit PGF(2)alpha synthesis and PGF(2)alpha is a key stimulator of MMP-2 production. Our data showed that PGF(2)alpha treatment attenuated the acetylsalicylic acid-inhibited invasion of B16F0 cells. In animal experiments, acetylsalicylic acid reduced colorectal metastasis of B16F0 cells in C57BL/6J mice by 44%. Our results suggest that PGF(2)alpha is a therapeutic target for metastasis inhibition and acetylsalicylic acid may possess anti-metastasis ability.
Chen, Yingying; Stabryla, Lisa
2016-01-01
Development of acetic acid-resistant Saccharomyces cerevisiae is important for economically viable production of biofuels from lignocellulosic biomass, but the goal remains a critical challenge due to limited information on effective genetic perturbation targets for improving acetic acid resistance in the yeast. This study employed a genomic-library-based inverse metabolic engineering approach to successfully identify a novel gene target, WHI2 (encoding a cytoplasmatic globular scaffold protein), which elicited improved acetic acid resistance in S. cerevisiae. Overexpression of WHI2 significantly improved glucose and/or xylose fermentation under acetic acid stress in engineered yeast. The WHI2-overexpressing strain had 5-times-higher specific ethanol productivity than the control in glucose fermentation with acetic acid. Analysis of the expression of WHI2 gene products (including protein and transcript) determined that acetic acid induced endogenous expression of Whi2 in S. cerevisiae. Meanwhile, the whi2Δ mutant strain had substantially higher susceptibility to acetic acid than the wild type, suggesting the important role of Whi2 in the acetic acid response in S. cerevisiae. Additionally, overexpression of WHI2 and of a cognate phosphatase gene, PSR1, had a synergistic effect in improving acetic acid resistance, suggesting that Whi2 might function in combination with Psr1 to elicit the acetic acid resistance mechanism. These results improve our understanding of the yeast response to acetic acid stress and provide a new strategy to breed acetic acid-resistant yeast strains for renewable biofuel production. PMID:26826231
Chen, Yingying; Stabryla, Lisa; Wei, Na
2016-01-29
Development of acetic acid-resistant Saccharomyces cerevisiae is important for economically viable production of biofuels from lignocellulosic biomass, but the goal remains a critical challenge due to limited information on effective genetic perturbation targets for improving acetic acid resistance in the yeast. This study employed a genomic-library-based inverse metabolic engineering approach to successfully identify a novel gene target, WHI2 (encoding a cytoplasmatic globular scaffold protein), which elicited improved acetic acid resistance in S. cerevisiae. Overexpression of WHI2 significantly improved glucose and/or xylose fermentation under acetic acid stress in engineered yeast. The WHI2-overexpressing strain had 5-times-higher specific ethanol productivity than the control in glucose fermentation with acetic acid. Analysis of the expression of WHI2 gene products (including protein and transcript) determined that acetic acid induced endogenous expression of Whi2 in S. cerevisiae. Meanwhile, the whi2Δ mutant strain had substantially higher susceptibility to acetic acid than the wild type, suggesting the important role of Whi2 in the acetic acid response in S. cerevisiae. Additionally, overexpression of WHI2 and of a cognate phosphatase gene, PSR1, had a synergistic effect in improving acetic acid resistance, suggesting that Whi2 might function in combination with Psr1 to elicit the acetic acid resistance mechanism. These results improve our understanding of the yeast response to acetic acid stress and provide a new strategy to breed acetic acid-resistant yeast strains for renewable biofuel production. Copyright © 2016, American Society for Microbiology. All Rights Reserved.
Kumar, Sandeep; Kayastha, Arvind M
2010-10-01
Various inhibitors were tested for their inhibitory effects on soybean urease. The K(i) values for boric acid, 4-bromophenylboronic acid, butylboronic acid, and phenylboronic acid were 0.20 +/- 0.05 mM, 0.22 +/- 0.04 mM, 1.50 +/- 0.10 mM, and 2.00 +/- 0.11 mM, respectively. The inhibition was competitive type with boric acid and boronic acids. Heavy metal ions including Ag(+), Hg(2+), and Cu(2+) showed strong inhibition on soybean urease, with the silver ion being a potent inhibitor (IC(50) = 2.3 x 10(-8) mM). Time-dependent inhibition studies exhibited biphasic kinetics with all heavy metal ions. Furthermore, inhibition studies with sodium salts of mineral acids (NaF, NaCl, NaNO(3), and Na(2)SO(4)) showed that only F(-) inhibited soybean urease significantly (IC(50) = 2.9 mM). Competitive type of inhibition was observed for this anion with a K(i) value of 1.30 mM.
40 CFR 721.10110 - Hexanoic acid, 2-ethyl-, mixed diesters with benzoic acid and neopentlyl glycol.
Code of Federal Regulations, 2011 CFR
2011-07-01
... 40 Protection of Environment 31 2011-07-01 2011-07-01 false Hexanoic acid, 2-ethyl-, mixed... SUBSTANCES Significant New Uses for Specific Chemical Substances § 721.10110 Hexanoic acid, 2-ethyl-, mixed... to reporting. (1) The chemical substance identified as hexanoic acid, 2-ethyl-, mixed diesters with...
40 CFR 721.10111 - Hexanoic acid, 2-ethyl-, mixed diesters with benzoic acid and diethylene glycol.
Code of Federal Regulations, 2011 CFR
2011-07-01
... 40 Protection of Environment 31 2011-07-01 2011-07-01 false Hexanoic acid, 2-ethyl-, mixed... SUBSTANCES Significant New Uses for Specific Chemical Substances § 721.10111 Hexanoic acid, 2-ethyl-, mixed... to reporting. (1) The chemical substance identified as hexanoic acid, 2-ethyl-, mixed diesters with...
40 CFR 721.10111 - Hexanoic acid, 2-ethyl-, mixed diesters with benzoic acid and diethylene glycol.
Code of Federal Regulations, 2013 CFR
2013-07-01
... 40 Protection of Environment 32 2013-07-01 2013-07-01 false Hexanoic acid, 2-ethyl-, mixed... SUBSTANCES Significant New Uses for Specific Chemical Substances § 721.10111 Hexanoic acid, 2-ethyl-, mixed... to reporting. (1) The chemical substance identified as hexanoic acid, 2-ethyl-, mixed diesters with...
40 CFR 721.10110 - Hexanoic acid, 2-ethyl-, mixed diesters with benzoic acid and neopentlyl glycol.
Code of Federal Regulations, 2013 CFR
2013-07-01
... 40 Protection of Environment 32 2013-07-01 2013-07-01 false Hexanoic acid, 2-ethyl-, mixed... SUBSTANCES Significant New Uses for Specific Chemical Substances § 721.10110 Hexanoic acid, 2-ethyl-, mixed... to reporting. (1) The chemical substance identified as hexanoic acid, 2-ethyl-, mixed diesters with...
40 CFR 721.10111 - Hexanoic acid, 2-ethyl-, mixed diesters with benzoic acid and diethylene glycol.
Code of Federal Regulations, 2012 CFR
2012-07-01
... 40 Protection of Environment 32 2012-07-01 2012-07-01 false Hexanoic acid, 2-ethyl-, mixed... SUBSTANCES Significant New Uses for Specific Chemical Substances § 721.10111 Hexanoic acid, 2-ethyl-, mixed... to reporting. (1) The chemical substance identified as hexanoic acid, 2-ethyl-, mixed diesters with...
40 CFR 721.10111 - Hexanoic acid, 2-ethyl-, mixed diesters with benzoic acid and diethylene glycol.
Code of Federal Regulations, 2014 CFR
2014-07-01
... 40 Protection of Environment 31 2014-07-01 2014-07-01 false Hexanoic acid, 2-ethyl-, mixed... SUBSTANCES Significant New Uses for Specific Chemical Substances § 721.10111 Hexanoic acid, 2-ethyl-, mixed... to reporting. (1) The chemical substance identified as hexanoic acid, 2-ethyl-, mixed diesters with...
40 CFR 721.10111 - Hexanoic acid, 2-ethyl-, mixed diesters with benzoic acid and diethylene glycol.
Code of Federal Regulations, 2010 CFR
2010-07-01
... 40 Protection of Environment 30 2010-07-01 2010-07-01 false Hexanoic acid, 2-ethyl-, mixed... SUBSTANCES Significant New Uses for Specific Chemical Substances § 721.10111 Hexanoic acid, 2-ethyl-, mixed... to reporting. (1) The chemical substance identified as hexanoic acid, 2-ethyl-, mixed diesters with...
40 CFR 721.10110 - Hexanoic acid, 2-ethyl-, mixed diesters with benzoic acid and neopentlyl glycol.
Code of Federal Regulations, 2014 CFR
2014-07-01
... 40 Protection of Environment 31 2014-07-01 2014-07-01 false Hexanoic acid, 2-ethyl-, mixed... SUBSTANCES Significant New Uses for Specific Chemical Substances § 721.10110 Hexanoic acid, 2-ethyl-, mixed... to reporting. (1) The chemical substance identified as hexanoic acid, 2-ethyl-, mixed diesters with...
40 CFR 721.10110 - Hexanoic acid, 2-ethyl-, mixed diesters with benzoic acid and neopentlyl glycol.
Code of Federal Regulations, 2012 CFR
2012-07-01
... 40 Protection of Environment 32 2012-07-01 2012-07-01 false Hexanoic acid, 2-ethyl-, mixed... SUBSTANCES Significant New Uses for Specific Chemical Substances § 721.10110 Hexanoic acid, 2-ethyl-, mixed... to reporting. (1) The chemical substance identified as hexanoic acid, 2-ethyl-, mixed diesters with...
40 CFR 721.10110 - Hexanoic acid, 2-ethyl-, mixed diesters with benzoic acid and neopentlyl glycol.
Code of Federal Regulations, 2010 CFR
2010-07-01
... 40 Protection of Environment 30 2010-07-01 2010-07-01 false Hexanoic acid, 2-ethyl-, mixed... SUBSTANCES Significant New Uses for Specific Chemical Substances § 721.10110 Hexanoic acid, 2-ethyl-, mixed... to reporting. (1) The chemical substance identified as hexanoic acid, 2-ethyl-, mixed diesters with...
Kahleova, Hana; Malinska, Hana; Kazdova, Ludmila; Belinova, Lenka; Tura, Andrea; Hill, Martin; Pelikanova, Terezie
2016-01-01
Fatty acids are important cellular constituents that can affect many metabolic processes relevant for the development of diabetes and its complications. We previously demonstrated a positive effect of eating just 2 meals a day, breakfast and lunch, compared to 6 small meals. The aim of this secondary analysis was to explore the effect of meal frequency on the fatty acid composition of serum phospholipids in subjects with type 2 diabetes (T2D). In a randomized, crossover study, we assigned 54 patients with T2D to follow one of 2 regimens of a hypocaloric diet (-500 kcal/day), each for 12 weeks: 6 meals (A6) or 2 meals a day, breakfast and lunch (B2). The diet in both regimens had the same macronutrient and energy content. The fatty acid composition of serum phospholipids was measured at weeks 0, 12, and 24, using gas liquid chromatography. Insulin sensitivity was derived as an oral glucose insulin sensitivity (OGIS) index. Saturated fatty acids (mainly myristic and palmitic acids) decreased (p < 0.001) and n6 polyunsaturated fatty acids increased (p < 0.001) in response to both regimens but more with B2 (p < 0.001 for both). Monounsaturated fatty acids decreased (p < 0.05) and n3 polyunsaturated fatty acids increased (p < 0.001) in response to both regimens, with no difference between the regimens. An increase in OGIS correlated positively with changes in the proportion of linoleic acid in B2. This correlation remained significant even after adjustment for changes in body mass index (BMI; r = +0.38; p = 0.012). We demonstrated that meal frequency affects the fatty acid composition of serum phospholipids. The B2 regimen had more marked positive effects, with saturated fatty acids and the ratio of saturated to unsaturated fatty acids decreasing more. The increase in linoleic acid could partly explain the insulin-sensitizing effect of B2 in T2D.
DOE Office of Scientific and Technical Information (OSTI.GOV)
McEntee, Monica; Tang, Wenjie; Neurock, Matthew
Here, the partial oxidation of model C 2–C 4 (acetic, propionic, and butyric) carboxylic acids on Au/TiO 2 catalysts consisting of Au particles ~3 nm in size was investigated using transmission infrared spectroscopy and density functional theory. All three acids readily undergo oxidative dehydrogenation on Au/TiO 2. Propionic and butyric acid dehydrogenate at the C2–C3 positions, whereas acetic acid dehydrogenates at the C1–C2 position. The resulting acrylate and crotonate intermediates are subsequently oxidized to form β-keto acids that decarboxylate. All three acids form a gold ketenylidene intermediate, Au 2C=C=O, along the way to their full oxidation to form CO 2.more » Infrared measurements of Au 2C=C=O formation as a function of time provides a surface spectroscopic probe of the kinetics for the activation and oxidative dehydrogenation of the alkyl groups in the carboxylate intermediates that form.« less
McEntee, Monica; Tang, Wenjie; Neurock, Matthew; ...
2014-12-12
Here, the partial oxidation of model C 2–C 4 (acetic, propionic, and butyric) carboxylic acids on Au/TiO 2 catalysts consisting of Au particles ~3 nm in size was investigated using transmission infrared spectroscopy and density functional theory. All three acids readily undergo oxidative dehydrogenation on Au/TiO 2. Propionic and butyric acid dehydrogenate at the C2–C3 positions, whereas acetic acid dehydrogenates at the C1–C2 position. The resulting acrylate and crotonate intermediates are subsequently oxidized to form β-keto acids that decarboxylate. All three acids form a gold ketenylidene intermediate, Au 2C=C=O, along the way to their full oxidation to form CO 2.more » Infrared measurements of Au 2C=C=O formation as a function of time provides a surface spectroscopic probe of the kinetics for the activation and oxidative dehydrogenation of the alkyl groups in the carboxylate intermediates that form.« less
NASA Astrophysics Data System (ADS)
Lin, Zhihao; Jin, Shouwen; Li, Xiaoliang; Xiao, Xiao; Hu, Kaikai; Guo, Ming; Chi, Xinchen; Liu, Hui; Wang, Daqi
2017-10-01
Cocrystallization of the aromatic brønsted bases with a series of mineral acids gave a total of ten hybrid salts with the compositions: (2-methylquinoline)2: (hydrochloride acid): 3H2O [(HL1)+. (L1)·· (Cl-) · (H2O)3] (1), (6-bromobenzo[d]thiazol-2-amine): (hydrochloride acid) [(HL2)+. (Cl-)] (2), (6-bromobenzo[d]thiazol-2-amine): (nitric acid) [(HL2)+. (NO3-)] (3), (6-bromobenzo[d]thiazol-2-amine): (sulfuric acid) [(HL2)+ · (HSO4)-] (4), (6-bromobenzo[d]thiazol-2-amine): (phosphoric acid) [(HL2)+ · (H2PO4)-] (5), (5,7-dimethyl-1,8-naphthyridine-2-amine): (hydrochloride acid): 3H2O [(HL3)+ · (Cl-) (H2O)3] (6), (5,7-dimethyl-1,8-naphthyridine-2-amine): (hydrobromic acid): CH3OH [(HL3)+ · (Br)- · CH3OH] (7), (5,7-dimethyl-1,8-naphthyridine-2-amine): (sulfuric acid): H2O [(HL3)+ · (HSO4)- · H2O] (8), (2-aminophenol): (phosphoric acid) [(HL4)+ · (H2PO4)-] (9), and (2-amino-4-chlorophenol): (phosphoric acid) [(HL5)+ · (H2PO4)-] (10). The ten salts have been characterized by X-ray diffraction analysis, IR, and elemental analysis, and the melting points of all the salts were also reported. And their structural and supramolecular aspects are fully analyzed. The result reveals that among the ten investigated crystals the ring N of the heterocycle or the NH2 in the aminophenol are protonated when the acids are deprotonated, and the crystal packing is interpreted in terms of the strong charge-assisted classical hydrogen bonds between the NH+/NH3+ and deprotonated acidic groups. Further analysis of the crystal packing of the salts indicated that a different family of additional CHsbnd O, CHsbnd Cl, CH3sbnd N, CH3sbnd O, CHsbnd Br, CH3sbnd Br, Brsbnd Cl, Clsbnd S, Osbnd S, Osbnd O, Brsbnd S, Hsbnd H, and π-π associations contribute to the stabilization and expansion of the total high-dimensional frameworks. For the coexistence of the various weak nonbonding interactions these structures adopted homo or hetero supramolecular synthons or both. Some classical supramolecular synthons, such as R22(8), R42(8), R43(10) and R44(12), usually observed in the organic solids, were again shown to be involved in constructing most of these H-bonding networks.
Fukushima, Keijo; Takahashi, Tadanobu; Ito, Seigo; Takaguchi, Masahiro; Takano, Maiko; Kurebayashi, Yuuki; Oishi, Kenta; Minami, Akira; Kato, Tatsuya; Park, Enoch Y; Nishimura, Hidekazu; Takimoto, Toru; Suzuki, Takashi
2014-09-01
Human parainfluenza virus type 1 (hPIV1) and type 3 (hPIV3) initiate infection by sialic acid binding. Here, we investigated sialic acid linkage specificities for binding and infection of hPIV1 and hPIV3 by using sialic acid linkage-modified cells treated with sialidases or sialyltransferases. The hPIV1 is bound to only α2,3-linked sialic acid residues, whereas hPIV3 is bound to α2,6-linked sialic acid residues in addition to α2,3-linked sialic acid residues in human red blood cells. α2,3 linkage-specific sialidase treatment of LLC-MK2 cells and A549 cells decreased the infectivity of hPIV1 but not that of hPIV3. Treatment of A549 cells with α2,3 linkage-specific sialyltransferase increased infectivities of both hPIV1 and hPIV3, whereas α2,6 linkage-specific sialyltransferase treatment increased only hPIV3 infectivity. Clinical isolates also showed similar sialic acid linkage specificities. We concluded that hPIV1 utilizes only α2,3 sialic acid linkages and that hPIV3 makes use of α2,6 sialic acid linkages in addition to α2,3 sialic acid linkages as viral receptors. Copyright © 2014. Published by Elsevier Inc.
Qin, Xiaopeng; Liu, Fei; Wang, Guangcai; Weng, Liping
2012-12-01
An accurate and fast method for simultaneous determination of small organic acids and much larger humic acids was developed using high performance size exclusion chromatography. Two small organic acids, i.e. salicylic acid and 2,3-dihydroxybenzoic acid, and one purified humic acid material were used in this study. Under the experimental conditions, the UV peaks of salicylic acid and 2,3-dihydroxybenzoic acid were well separated from the peaks of humic acid in the chromatogram. Concentrations of the two small organic acids could be accurately determined from their peak areas. The concentration of humic acid in the mixture could then be derived from mass balance calculations. The measured results agreed well with the nominal concentrations. The detection limits are 0.05 mg/L and 0.01 mg/L for salicylic acid and 2,3-dihydroxybenzoic acid, respectively. Applicability of the method to natural samples was tested using groundwater, glacier, and river water samples (both original and spiked with salicylic acid and 2,3-dihydroxybenzoic acid) with a total organic carbon concentration ranging from 2.1 to 179.5 mg C/L. The results obtained are promising, especially for groundwater samples and river water samples with a total organic carbon concentration below 9 mg C/L. © 2012 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.
Cahoon, E B; Ripp, K G; Hall, S E; Kinney, A J
2001-01-26
Divergent forms of the plant Delta(12)-oleic-acid desaturase (FAD2) have previously been shown to catalyze the formation of acetylenic bonds, epoxy groups, and conjugated Delta(11),Delta(13)-double bonds by modification of an existing Delta(12)-double bond in C(18) fatty acids. Here, we report a class of FAD2-related enzymes that modifies a Delta(9)-double bond to produce the conjugated trans-Delta(8),trans-Delta(10)-double bonds found in calendic acid (18:3Delta(8trans,10trans,12cis)), the major component of the seed oil of Calendula officinalis. Using an expressed sequence tag approach, cDNAs for two closely related FAD2-like enzymes, designated CoFADX-1 and CoFADX-2, were identified from a C. officinalis developing seed cDNA library. The deduced amino acid sequences of these polypeptides share 40-50% identity with those of other FAD2 and FAD2-related enzymes. Expression of either CoFADX-1 or CoFADX-2 in somatic soybean embryos resulted in the production of calendic acid. In embryos expressing CoFADX-2, calendic acid accumulated to as high as 22% (w/w) of the total fatty acids. In addition, expression of CoFADX-1 and CoFADX-2 in Saccharomyces cerevisiae was accompanied by calendic acid accumulation when induced cells were supplied exogenous linoleic acid (18:2Delta(9cis,12cis)). These results are thus consistent with a route of calendic acid synthesis involving modification of the Delta(9)-double bond of linoleic acid. Regiospecificity for Delta(9)-double bonds is unprecedented among FAD2-related enzymes and further expands the functional diversity found in this family of enzymes.
Lu, Yapeng; Liu, Siyuan; Wang, Ying; Wang, Dang; Gao, Jing; Zhu, Li
2016-09-05
Asiatic acid, one of the triterpenoid components isolated from Centella asiatica, has received increasing attention due to a wide variety of biological activities. To date, little is known about its mechanisms of action. Here we examined the cytotoxic effect of asiatic acid on HepG2 cells and elucidated some of the underlying mechanisms. Asiatic acid induced rapid cell death, as well as mitochondrial membrane potential (MMP) dissipation, ATP depletion and cytochrome c release from mitochondria to the cytosol in HepG2 cells. In mitochondria isolated from mouse liver, asiatic acid treatment significantly stimulated the succinate-supported state 4 respiration rate, dissipated the MMP, increased Ca(2+) release from Ca(2+)-loaded mitochondria, decreased ATP content and promoted cytochrome c release, indicating the uncoupling effect of asiatic acid. Hydrogen peroxide (H2O2) produced by succinate-supported mitochondrial respiration was also significantly inhibited by asiatic acid. In addition, asiatic acid inhibited Ca(2+)-induced mitochondrial swelling but did not induce mitochondrial swelling in hyposmotic potassium acetate medium which suggested that asiatic acid may not act as a protonophoric uncoupler. Inhibition of uncoupling proteins (UCPs) or blockade of adenine nucleotide transporter (ANT) attenuated the effect of asiatic acid on MMP dissipation, Ca(2+) release, mitochondrial respiration and HepG2 cell death. When combined inhibition of UCPs and ANT, asiatic acid-mediated uncoupling effect was noticeably alleviated. These results suggested that both UCPs and ANT partially contribute to the uncoupling properties of asiatic acid. In conclusion, asiatic acid is a novel mitochondrial uncoupler and this property is potentially involved in its toxicity on HepG2 cells. Copyright © 2016 Elsevier B.V. All rights reserved.
Nunn, Peter B; Codd, Geoffrey A
2017-12-01
The non-encoded diaminomonocarboxylic acids, 3-N-methyl-2,3-diaminopropanoic acid (syn: α-amino-β-methylaminopropionic acid, MeDAP; β-N-methylaminoalanine, BMAA) and 2,4-diaminobutanoic acid (2,4-DAB), are distributed widely in cyanobacterial species in free and bound forms. Both amino acids are neurotoxic in whole animal and cell-based bioassays. The biosynthetic pathway to 2,4-DAB is well documented in bacteria and in one higher plant species, but has not been confirmed in cyanobacteria. The biosynthetic pathway to BMAA is unknown. This review considers possible metabolic routes, by analogy with reactions used in other species, by which these amino acids might be biosynthesised by cyanobacteria, which are a widespread potential environmental source of these neurotoxins. Where possible, the gene expression that might be implicated in these biosyntheses is discussed. Copyright © 2017 Elsevier Ltd. All rights reserved.
Spectroscopic and thermodynamic studies on ferulic acid - Alpha-2-macroglobulin interaction
NASA Astrophysics Data System (ADS)
Rehman, Ahmed Abdur; Sarwar, Tarique; Arif, Hussain; Ali, Syed Saqib; Ahsan, Haseeb; Tabish, Mohammad; Khan, Fahim Halim
2017-09-01
Ferulic acid is a major phenolic acid found in numerous plant species in conjugated form. It binds to enzymes and oligomeric proteins and modifies their structure and function. This study was designed to examine the interaction of ferulic acid, an active ingredient of some important medicines, with α2M, a key serum proteinase, under physiological conditions. The mechanism of interaction was studied by spectroscopic techniques such as, UV-visible absorption, fluorescence spectroscopy, circular dichroism along with isothermal titration calorimetry. Fluorescence quenching of α2M by ferulic acid demonstrated the formation of α2M-ferulic acid complex by static quenching mechanism. Binding parameters calculated by Stern-Volmer method showed that ferulic acid binds to α2M with moderate affinity of the order of ∼104 M-1. The thermodynamic signatures reveal that binding was enthalpy driven and hydrogen bonding played a major role in ferulic acid-α2M binding. CD spectra analysis suggests very little conformational changes in α2M on ferulic acid binding.
Additive free preparative chiral SFC separations of 2,2-dimethyl-3-aryl-propanoic acids.
Wu, Dauh-Rurng; Yip, Shiuhang Henry; Li, Peng; Sun, Dawn; Kempson, James; Mathur, Arvind
2016-11-30
A series of racemic 2,2-dimethyl-3-aryl-propanoic acids were resolved by chiral supercritical fluid chromatography (SFC) without the use of an acidic additive, trifluoroacetic acid (TFA). The use of additive-free protic methanol as co-solvent in CO 2 was expanded to successfully resolve other series of carboxylic acid containing racemates. Large-scale SFC of racemic acid 4, 3-(1-(4-fluorophenyl)-1H-indazol-5-yl)-2,2-dimethyl-3-phenylpropanoic acid, in methanol without TFA as additive on both Chiralpak AD-H and Chiralcel OJ-H will be discussed, along with impact on throughput and solvent consumption. Investigation of co-solvent effect on peak sharpening of acid racemate 20, 2-(2-chloro-9-fluoro-5H-chromeno[2,3-b]pyridin-5-yl)-2-methylpropanoic acid, without TFA further indicated that methanol in CO 2 provided improved peak shape compared with isopropanol (IPA) and acetonitrile. Finally, we discuss the resolution of basic aromatic chiral amines without the addition of basic additives such as diethylamine (DEA) and application of this protocol for the large-scale SFC separation of weakly basic indazole-containing racemate 14, methyl 3-(1H-indazol-5-yl)-2,2-dimethyl-3-phenylpropanoate, in methanol without DEA. Copyright © 2016 Elsevier B.V. All rights reserved.
Jones, Rachel A; Cheung, Charles Y; Black, Fiona E; Zia, Jasmine K; Stayton, Patrick S; Hoffman, Allan S; Wilson, Mark R
2003-05-15
The permeability barrier posed by cell membranes represents a challenge for the delivery of hydrophilic molecules into cells. We previously proposed that poly(2-alkylacrylic acid)s are endocytosed by cells into acidified vesicles and are there triggered by low pH to disrupt membranes and release the contents of endosomes/lysosomes to the cytosol. If this hypothesis is correct, these polymers could be valuable in drug-delivery applications. The present paper reports functional comparisons of a family of three poly(2-alkylacrylic acid)s. Poly(2-propylacrylic acid) (PPAA), poly(2-ethylacrylic acid) (PEAA) and poly(2-methylacrylic acid) (PMAA) were compared in red-blood-cell haemolysis assays and in a lipoplex (liposome-DNA complex) assay. We also directly examined the ability of these polymers to disrupt endosomes and lysosomes in cultured human cells. Our results show that: (i) unlike membrane-disruptive peptides, the endosomal-disruptive ability of poly(2-alkylacrylic acid)s cannot necessarily be predicted from their haemolytic activity at low pH, (ii) PPAA (but not PEAA or PMAA) potently facilitates gene transfection by cationic lipoplexes and (iii) endocytosed poly(2-alkylacrylic acid)s are triggered by luminal acidification to selectively disrupt endosomes (not lysosomes) and release their contents to the cytosol. These results will facilitate the rational design of future endosomal-disrupting polymers for drug delivery.
Aromatic Hydroxylation of Salicylic Acid and Aspirin by Human Cytochromes P450
Bojić, Mirza; Sedgeman, Carl A.; Nagy, Leslie D.; Guengerich, F. Peter
2015-01-01
Aspirin (acetylsalicylic acid) is a well-known and widely-used analgesic. It is rapidly deacetylated to salicylic acid, which forms two hippuric acids—salicyluric acid and gentisuric acid—and two glucuronides. The oxidation of aspirin and salicylic acid has been reported with human liver microsomes, but data on individual cytochromes P450 involved in oxidation is lacking. In this study we monitored oxidation of these compounds by human liver microsomes and cytochrome P450 (P450) using UPLC with fluorescence detection. Microsomal oxidation of salicylic acid was much faster than aspirin. The two oxidation products were 2,5-dihydroxybenzoic acid (gentisic acid, documented by its UV and mass spectrum) and 2,3-dihydroxybenzoic acid. Formation of neither product was inhibited by desferrioxamine, suggesting a lack of contribution of oxygen radicals under these conditions. Although more liphophilic, aspirin was oxidized less efficiently, primarily to the 2,5-dihydroxy product. Recombinant human P450s 2C8, 2C9, 2C19, 2D6, 2E1, and 3A4 all catalyzed the 5-hydroxylation of salicylic acid. Inhibitor studies with human liver microsomes indicated that all six of the previously mentioned P450s could contribute to both the 5- and 3-hydroxylation of salicylic acid and that P450s 2A6 and 2B6 have contributions to 5-hydroxylation. Inhibitor studies indicated that the major human P450 involved in both 3- and 5-hydroxylation of salicylic acid is P450 2E1. PMID:25840124
Lamberto, M; Ackman, R G
1995-09-20
The effect of derivatization with 2-amino-2-methyl-propanol on trans-3-hexadecenoic acid was investigated as part of the identification of the trans-3-hexadecenoic acid in two Nova Scotian seaweeds. After the extraction of the total fatty acids and their methylation, the monoenoic trans fraction was isolated by thin-layer chromatography on silica gels impregnated with silver nitrate. This fraction was first analyzed by gas chromatography and showed the presence of the trans-3-hexadecenoic acid; other fatty acids were not present. The isolated fraction was derivatized with 2-amino-2-methyl-propanol prior to analysis by gas chromatography/mass spectrometry. The chromatogram obtained showed the presence of a positional isomer formed during the derivatization of the trans-3-hexadecenoic acid. The mass spectrum showed a prominent [M+H] and diagnostic ions for the identification of the unknown isomer, corresponding to the 4,4-dimethyloxazoline (DMOX) derivative of a presumed 2-hexadecenoic acid. Definitive confirmation of the ethylenic bond position was obtained by oxidative ozonolysis of the DMOX derivatives of the fatty acids under investigation. Infrared spectroscopy showed that the artifact formed during the DMOX derivatization of trans-3-hexadecenoic acid was the DMOX derivative of cis-2-hexadecenoic acid.
EVALUATION OF THE SYNTHESIS AND STRUCTURE OF NEW AZETIDIN-2-ONES OF FERULIC ACID.
Stan, Cătălina Daniela; Drăgan, Maria; Pânzariu, Andreea; Profire, Lenuţa
2016-01-01
To synthesize some new azetidin-2-ones of ferulic acid and to evaluate them from physicochemical and spectral point of view. The synthesis was carried out in several steps: (i) obtaining the ferulic acid chloride; (ii) obtaining the ferulic acid hydrazide with hydrazine hydrate (98%); (iii) condensation of ferulic acid hydrazide with different benzaldehydes (2-hydroxy-/2-nitro-/4-chloro-/4- fluoro-/4-bromo-benzaldehyde) in order to obtain the corresponding hydrazones; (iv) cy- clization of ferulic acid hydrazones with chloroacethyl chloride in freshly distilled toluene medium and in the presence of triethylamine, resulting in the corresponding azetidin-2-ones. Six new azetidin-2-ones of ferulic acid were synthesized. They were characterized in terms of their physicochemical properties and their structure was confirmed by IR and 1H-NMR spectroscopy. Six new azetidin-2-ones of ferulic acid were synthesized, physicochemically characterized and validated spectrally. A
Bosco, Renato; Daeseleire, Els; Van Pamel, Els; Scariot, Valentina; Leus, Leen
2014-07-09
This paper describes a method to detect and quantitate the endogenous plant hormones (±)-2-cis-4-trans-abscisic acid, (-)-jasmonic acid, and salicylic acid by means of ultrahigh-performance liquid chromatography-tandem mass spectrometry (UHPLC-MS/MS) in hybrid rose leaf matrices. Deuterium-labeled [(2)H6] (+)-2-cis-4-trans-abscisic acid, [(2)H6] (±)-jasmonic acid, and [(2)H4]-salicylic acid were used as internal standards. Rose samples (10 mg) were extracted with methanol/water/acetic acid (10:89:1) and subsequently purified on an Oasis MCX 1 cm(3) Vac SPE cartridge. Performance characteristics were validated according to Commission Decision 2002/657/EC. Recovery, repeatability, and within-laboratory reproducibility were acceptable for all phytohormones tested at three different concentrations. The decision limit and detection capability for (±)-2-cis-4-trans-abscisic acid, (-)-jasmonic acid, and salicylic acid were 0.0075 and 0.015 μg/g, 0.00015 and 0.00030 μg/g, and 0.0089 and 0.018 μg/g, respectively. Matrix effects (signal suppression or enhancement) appeared to be high for all substances considered, implying the need for quantitation based on matrix-matched calibration curves.
Liu, Linna; Liu, Zhenxiong; Zhang, Tian; Shi, Lei; Zhang, Wenjuan; Zhang, Yan
2015-06-01
The most common conventional therapy for inflammatory bowel disease in clinical practice involves the use of nonsteroidal anti-inflammatory drugs, such as 5-amino salicylic acid. However, a high dose of 5-amino salicylic acid may bring about severe side effects. Chinese people have used Rheum tanguticum as a folk remedy for gastrointestinal disease for two thousand years. Our group has isolated R. tanguticum polysaccharide 1 from R. tanguticum and verified that it can attenuate 2,4,6-trinitrobenzene sulfonic acid-induced colitis in murines/rats. The present study aims to evaluate whether the addition of R. tanguticum polysaccharide 1 can improve efficacy and limit subsequent side effects of conventional treatment (5-amino salicylic acid) in rats with 2,4,6-trinitrobenzene sulfonic acid-induced colitis. Sixty Sprague-Dawley male rats were randomized into five groups and treated with (1) saline (saline, 0.2 mL/day × 5, p. o.), (2) 2,4,6-trinitrobenzene sulfonic acid alone (saline, 0.2 mL/day × 5, p. o.), (3) 2,4,6-trinitrobenzene sulfonic acid + 5-amino salicylic acid (5-amino salicylic acid, 75 mg/kg/day × 5, p.o), (4) 2,4,6-trinitrobenzene sulfonic acid + R. tanguticum polysaccharide 1 (R. tanguticum polysaccharide 1, 200 mg/kg/day × 5, p. o.), and (5) 2,4,6-trinitrobenzene sulfonic acid + 5-amino salicylic acid + R. tanguticum polysaccharide 1 (5-amino salicylic acid, 25 mg/kg/day × 5, p.o; R. tanguticum polysaccharide 1, 200 mg/kg/day × 5, p. o.). All the rats were sacrificed on the 6th day after treatment using an overdose of anesthesia. A histological assessment was performed using semiquantitative scores; nuclear factor-kappa B and tumor necrosis factor-α were measured with Western blot, cyclooxygenase 1 and cyclooxygenase 2 protein expressions were investigated by RT-polymerase chain reaction, and prostoglandin E2 and inducible nitric oxide synthase productions were investigated by ELISA. The extent and severity of histological signs were attenuated significantly in the 2,4,6-trinitrobenzene sulfonic acid + 5-amino salicylic acid + R. tanguticum polysaccharide 1 group. Treatment with R. tanguticum polysaccharide 1 plus 5-amino salicylic acid markedly decreased nuclear factor-kappa Bp65 and tumor necrosis factor-α protein expressions. R. tanguticum polysaccharide 1 and 5-amino salicylic acid had no effect on cyclooxygenase 1 protein expression, but inhibited the overexpression of the cyclooxygenase 2 protein. After treatment with 5-amino salicylic acid and R. tanguticum polysaccharide 1, the prostoglandin E2 level increased significantly and the inducible nitric oxide synthase level decreased considerably in the 2,4,6-trinitrobenzene sulfonic acid + 5-amino salicylic acid + R. tanguticum polysaccharide 1 group compared with the 2,4,6-trinitrobenzene sulfonic acid alone group. These results demonstrate that combined therapy with R. tanguticum polysaccharide 1 and low-dose 5-amino salicylic acid had more favorable effects on 2,4,6-trinitrobenzene sulfonic acid-induced colitis in rats, and its effects may be associated with inhibiting nuclear factor-kappa Bp65 protein expression and tumor necrosis factor-α production, resulting in a decrease of cyclooxygenase 2 and inducible nitric oxide synthase protein expressions. Georg Thieme Verlag KG Stuttgart · New York.
Ohta, Kazutoku; Ohashi, Masayoshi; Jin, Ji-Ye; Takeuchi, Toyohide; Fujimoto, Chuzo; Choi, Seong-Ho; Ryoo, Jae-Jeong; Lee, Kwang-Pill
2003-05-16
The application of various hydrophilic cation-exchange resins for high-performance liquid chromatography (sulfonated silica gel: TSKgel SP-2SW, carboxylated silica gel: TSKgel CM-2SW, sulfonated polymethacrylate resin: TSKgel SP-5PW, carboxylated polymethacrylate resins: TSKgel CM-5PW and TSKgel OA-Pak A) as stationary phases in ion-exclusion chromatography for C1-C7 aliphatic carboxylic acids (formic, acetic, propionic, butyric, isovaleric, valeric, isocaproic, caproic, 2-methylhexanoic and heptanoic acids) and benzenecarboxylic acids (pyromellitic, trimellitic, hemimellitic, o-phthalic, m-phthalic, p-phthalic, benzoic, salicylic acids and phenol) was carried out using diluted sulfuric acid as the eluent. Silica-based cation-exchange resins (TSKgel SP-2SW and TSKgel CM-2SW) were very suitable for the ion-exclusion chromatographic separation of these benzenecarboxylic acids. Excellent simultaneous separation of these benzenecarboxylic acids was achieved on a TSKgel SP-2SW column (150 x 6 mm I.D.) in 17 min using a 2.5 mM sulfuric acid at pH 2.4 as the eluent. Polymethacrylate-based cation-exchange resins (TSKgel SP-5PW, TSKgel CM-5PW and TSKgel OA-Pak A) acted as advanced stationary phases for the ion-exclusion chromatographic separation of these C1-C7 aliphatic carboxylic acids. Excellent simultaneous separation of these C1-C7 acids was achieved on a TSKgel CM-5PW column (150 x 6 mm I.D.) in 32 min using a 0.05 mM sulfuric acid at pH 4.0 as the eluent.
Olson, Robert J.; Trumble, Thomas E.; Gamble, Wilbert
1974-01-01
2,4-Dichlorophenoxyacetic acid and 2,4,5-trichlorophenoxyacetic acid inhibited the incorporation of [2-14C]mevalonate into cholesterol and non-saponifiable lipids. Both compounds inhibited the conversion of [1-14C]isopentenyl pyrophosphate into cholesterol and the synthesis of cholesterol and fatty acids from [2-14C]acetate. There was no inhibition of the conversion of [1-14C]mevalonate into CO2. At low concentrations (0.5mm) of the compounds there was a stimulation of acetate incorporation into fatty acids. PMID:4441387
Occurrence ofCis-6-hexadecenoic acid as the major component ofThunbergia alata seed oil.
Spencer, G F; Kleiman, R; Miller, R W; Earle, F R
1971-10-01
An unusual series of monoenoic fatty acids constitutes about 85% of the total acids in seed oil fromThunbergia alata. The major component in the oil,cis-6-hexadecenoic acid (82%), is accompanied by the homologous 4-tetradecenoic (ca. 0.2%) and 8-octadecenoic (1.8%) acids. Another homologous series is represented by 5-tetradecenoic (ca. 0.2%), 7-hexadecenoic (1.8%) and the familiar 9-octadecenoic (4.4%) acids. Traces (<0.1%) of three other acids, 6-tetradecenoic and 10- and 11-octadecenoic, are also present along with palmitic (5.8%), stearic (0.6%) and linoleic (2.2%) acids. Some of the monoenoic acids have not previously been known to occur in seed oils.
Dachineni, Rakesh; Kumar, D. Ramesh; Callegari, Eduardo; Kesharwani, Siddharth S.; Sankaranarayanan, Ranjini; Seefeldt, Teresa; Tummala, Hemachand; Bhat, G. Jayarama
2017-01-01
Aspirin's potential as a drug continues to be evaluated for the prevention of colorectal cancer (CRC). Although multiple targets for aspirin and its metabolite, salicylic acid, have been identified, no unifying mechanism has been proposed to clearly explain its chemopreventive effects. Our goal here was to investigate the ability of salicylic acid metabolites, known to be generated through cytochrome P450 (CYP450) enzymes, and its derivatives as cyclin dependent kinase (CDK) inhibitors to gain new insights into aspirin's chemopreventive actions. Using in vitro kinase assays, for the first time, we demonstrate that salicylic acid metabolites, 2,3-dihydroxy-benzoic acid (2,3-DHBA) and 2,5-dihydroxybenzoic acid (2,5-DHBA), as well as derivatives 2,4-dihydroxybenzoic acid (2,4-DHBA), 2,6-dihydroxybenzoic acid (2,6-DHBA), inhibited CDK1 enzyme activity. 2,3-DHBA and 2,6-DHBA did not inhibit CDK2 and 4; however, both inhibited CDK-6 activity. Interestingly, another derivative, 2,4,6-trihydroxybenzoic acid (2,4,6-THBA) was highly effective in inhibiting CDK1, 2, 4 and 6 activity. Molecular docking studies showed that these compounds potentially interact with CDK1. Immunoblotting experiments showed that aspirin acetylated CDK1, and pre-incubation with salicylic acid and its derivatives prevented aspirin-mediated CDK1 acetylation, which supported the data obtained from molecular docking studies. We suggest that intracellularly generated salicylic acid metabolites through CYP450 enzymes within the colonic epithelial cells, or the salicylic acid metabolites generated by gut microflora may significantly contribute to the preferential chemopreventive effect of aspirin against CRC through inhibition of CDKs. This novel hypothesis and mechanism of action in aspirin's chemopreventive effects opens a new area for future research. In addition, structural modification to salicylic acid derivatives may prove useful in the development of novel CDK inhibitors in cancer prevention and treatment. PMID:29075787
Cao, Fang; Zhang, Shi-Chun; Kawamura, Kimitaka; Liu, Xiaoyan; Yang, Chi; Xu, Zufei; Fan, Meiyi; Zhang, Wenqi; Bao, Mengying; Chang, Yunhua; Song, Wenhuai; Liu, Shoudong; Lee, Xuhui; Li, Jun; Zhang, Gan; Zhang, Yan-Lin
2017-12-01
Fine particulate matter (PM2.5) samples were collected using a high-volume air sampler and pre-combusted quartz filters during May 2013 to January 2014 at a background rural site (47 ∘ 35 N, 133 ∘ 31 E) in Sanjiang Plain, Northeast China. A homologous series of dicarboxylic acids (C 2 -C 11 ) and related compounds (oxoacids, α-dicarbonyls and fatty acids) were analyzed by using a gas chromatography (GC) and GC-MS method employing a dibutyl ester derivatization technique. Intensively open biomass-burning (BB) episodes during the harvest season in fall were characterized by high mass concentrations of PM2.5, dicarboxylic acids and levoglucosan. During the BB period, mass concentrations of dicarboxylic acids and related compounds were increased by up to >20 times with different factors for different organic compounds (i.e., succinic (C 4 ) acid > oxalic (C 2 ) acid > malonic (C 3 ) acid). High concentrations were also found for their possible precursors such as glyoxylic acid (ωC 2 ), 4-oxobutanoic acid, pyruvic acid, glyoxal, and methylglyoxal as well as fatty acids. Levoglucosan showed strong correlations with carbonaceous aerosols (OC, EC, WSOC) and dicarboxylic acids although such good correlations were not observed during non-biomass-burning seasons. Our results clearly demonstrate biomass burning emissions are very important contributors to dicarboxylic acids and related compounds. The selected ratios (e.g., C 3 /C 4 , maleic acid/fumaric acid, C 2 /ωC 2 , and C 2 /levoglucosan) were used as tracers for secondary formation of organic aerosols and their aging process. Our results indicate that organic aerosols from biomass burning in this study are fresh without substantial aging or secondary production. The present chemical characteristics of organic compounds in biomass-burning emissions are very important for better understanding the impacts of biomass burning on the atmosphere aerosols. Copyright © 2017 Elsevier Ltd. All rights reserved.
Interaction of model aryl- and alkyl-boronic acids and 1,2-diols in aqueous solution.
Marinaro, William A; Prankerd, Richard; Kinnari, Kaisa; Stella, Valentino J
2015-04-01
The goal of this work was to quantitate ester formation between alkyl and aryl boronic acids and vicinal-diols or 1,2-diols in aqueous solution. As used here, 1,2-diols includes polyols with one or more 1,2-diol pairs. Multiple techniques were used including apparent pKa shifts of the boronic acids using UV spectrophotometry (for aryl acids) and titration (for aryl and alkyl acids). Isothermal microcalorimetry was also used, with all reactions being enthalpically favored. For all the acids and 1,2-diols and the conditions studied, evidence only supported 1:1 ester formation. All the esters formed were found to be significantly more acidic, as Lewis acids, by 3-3.5 pKa units than the corresponding nonesterified boronic acid. The equilibrium constants for ester formation increased with increasing number of 1,2-diol pairs but stereochemistry may also play a role as sorbitol with five possible 1,2-diol pairs and five isomers (taking into account the stereochemistry of the alcohol groups) was twice as efficient at ester formation compared with mannitol, also with five possible 1,2-diol pairs but only three isomers. Alkyl boronic acids formed esters to a greater extent than aryl acids. Although some quantitative differences were seen between the various techniques used, rank ordering of the structure/reactivity was consistent. Formulation implications of ester formation between boronic acids and 1,2-diols are discussed. © 2015 Wiley Periodicals, Inc. and the American Pharmacists Association.
A Novel Concept of Amino Acid Supplementation to Improve the Growth of Young Malnourished Male Rats.
Furuta, Chie; Murakami, Hitoshi
2018-01-01
This study was aimed at understanding the relationship between plasma amino acids and protein malnutrition and at determining whether amino acid supplementation associated with malnutrition and growth improves linear growth in growing rats. Body length and plasma amino acids were measured in young male rats that were fed the following diet for 3 weeks, mimicking a low and imbalanced protein diets based on maize, a major staple consumed in developing countries: a 70% calorically restricted cornmeal-based diet (C), C + micronutrients (CM), CM + casein (CMC), CM + soy protein (CMS) or CMS + 0.3% lysine. A correlation analysis of linear growth and plasma amino acids indicated that lysine, tryptophan, branched-chain amino acids, methionine, and phenylalanine significantly correlated with body length. Supplementation with these 5 amino acids (AA1) significantly improved the body length in rats compared to CMC treatment whereas, nitrogen-balanced amino acid supplemented controls (AA2) did not (CM +1.2 ± 0.2, CMC +2.7 ± 0.3, CMS +2.1 ± 0.3, AA1 +2.8 ± 0.2, and AA2 +2.5 ± 0.3 cm). With securing proper amino acid balance, supplementing growth-related amino acids is more effective in improving linear growth in malnourished growing male rats. Analysis of the correlation between plasma amino acids and growth represents a powerful tool to determine candidate amino acids for supplementation to prevent malnutrition. This technology is adaptable to children in developing countries. © 2018 S. Karger AG, Basel.
Synthesis and Hydrolytic Degradation of Substituted Poly(DL-Lactic Acid)s
Tsuji, Hideto; Eto, Takehiko; Sakamoto, Yuzuru
2011-01-01
Non-substituted racemic poly(DL-lactic acid) (PLA) and substituted racemic poly(DL-lactic acid)s or poly(DL-2-hydroxyalkanoic acid)s with different side-chain lengths, i.e., poly(DL-2-hydroxybutanoic acid) (PBA), poly(DL-2-hydroxyhexanoic acid) (PHA), and poly(DL-2-hydroxydecanoic acid) (PDA) were synthesized by acid-catalyzed polycondensation of DL-lactic acid (LA), DL-2-hydroxybutanoic acid (BA), DL-2-hydroxyhexanoic acid (HA), and DL-2-hydroxydecanoic acid (DA), respectively. The hydrolytic degradation behavior was investigated in phosphate-buffered solution at 80 and 37 °C by gravimetry and gel permeation chromatography. It was found that the reactivity of monomers during polycondensation as monitored by the degree of polymerization (DP) decreased in the following order: LA > DA > BA > HA. The hydrolytic degradation rate traced by DP and weight loss at 80 °C decreased in the following order: PLA > PDA > PHA > PBA and that monitored by DP at 37 °C decreased in the following order: PLA > PDA > PBA > PHA. LA and PLA had the highest reactivity during polymerization and hydrolytic degradation rate, respectively, and were followed by DA and PDA. BA, HA, PBA, and PHA had the lowest reactivity during polymerization and hydrolytic degradation rate. The findings of the present study strongly suggest that inter-chain interactions play a major role in the reactivity of non-substituted and substituted LA monomers and degradation rate of the non-substituted and substituted PLA, along with steric hindrance of the side chains as can be expected. PMID:28824149
DOE Office of Scientific and Technical Information (OSTI.GOV)
Melton, Elaina M.; Center for Cardiovascular Sciences, Albany Medical College, Albany, NY; Cerny, Ronald L.
Highlights: •Roles of FATP2 in fatty acid transport/activation contribute to lipid homeostasis. •Use of 13C- and D-labeled fatty acids provide novel insights into FATP2 function. •FATP2-dependent trafficking of FA into phospholipids results in distinctive profiles. •FATP2 functions in the transport and activation pathways for exogenous fatty acids. -- Abstract: In mammals, the fatty acid transport proteins (FATP1 through FATP6) are members of a highly conserved family of proteins, which function in fatty acid transport proceeding through vectorial acylation and in the activation of very long chain fatty acids, branched chain fatty acids and secondary bile acids. FATP1, 2 and 4,more » for example directly function in fatty acid transport and very long chain fatty acids activation while FATP5 does not function in fatty acid transport but activates secondary bile acids. In the present work, we have used stable isotopically labeled fatty acids differing in carbon length and saturation in cells expressing FATP2 to gain further insights into how this protein functions in fatty acid transport and intracellular fatty acid trafficking. Our previous studies showed the expression of FATP2 modestly increased C16:0-CoA and C20:4-CoA and significantly increased C18:3-CoA and C22:6-CoA after 4 h. The increases in C16:0-CoA and C18:3-CoA suggest FATP2 must necessarily partner with a long chain acyl CoA synthetase (Acsl) to generate C16:0-CoA and C18:3-CoA through vectorial acylation. The very long chain acyl CoA synthetase activity of FATP2 is consistent in the generation of C20:4-CoA and C22:6-CoA coincident with transport from their respective exogenous fatty acids. The trafficking of exogenous fatty acids into phosphatidic acid (PA) and into the major classes of phospholipids (phosphatidylcholine (PC), phosphatidylethanolamine (PE), phosphatidylinositol (PI), and phosphatidyserine (PS)) resulted in distinctive profiles, which changed with the expression of FATP2. The trafficking of exogenous C16:0 and C22:6 into PA was significant where there was 6.9- and 5.3-fold increased incorporation, respectively, over the control; C18:3 and C20:4 also trended to increase in the PA pool while there were no changes for C18:1 and C18:2. The trafficking of C18:3 into PC and PI trended higher and approached significance. In the case of C20:4, expression of FATP2 resulted in increases in all four classes of phospholipid, indicating little selectivity. In the case of C22:6, there were significant increases of this exogenous fatty acids being trafficking into PC and PI. Collectively, these data support the conclusion that FATP2 has a dual function in the pathways linking the transport and activation of exogenous fatty acids. We discuss the differential roles of FATP2 and its role in both fatty acid transport and fatty acid activation in the context of lipid homeostasis.« less
Spectroscopic studies on the antioxidant activity of p-coumaric acid
NASA Astrophysics Data System (ADS)
Kiliç, Ismail; Yeşiloğlu, Yeşim
2013-11-01
p-coumaric acid (4-hydroxycinnamic acid), a phenolic acid, is a hydroxyl derivative of cinnamic acid. It decreases low density lipoprotein (LDL) peroxidation and reduces the risk of stomach cancer. In vitro radical scavenging and antioxidant capacity of p-coumaric acid were clarified using different analytical methodologies such as total antioxidant activity determination by ferric thiocyanate, hydrogen peroxide scavenging, 1,1-diphenyl-2-picryl-hydrazyl free radical (DPPH) scavenging, 2,2‧-azino-bis(3-ethylbenzthiazoline-6-sulphonic acid) (ABTS) radical scavenging activity and superoxide anion radical scavenging, ferrous ions (Fe2+) chelating activity and ferric ions (Fe3+) reducing ability. p-Coumaric acid inhibited 71.2% lipid peroxidation of a linoleic acid emulsion at 45 μg/mL concentration. On the other hand, butylated hydroxyanisole (BHA), butylated hydroxytoluene (BHT), α-tocopherol and ascorbic acid displayed 66.8%, 69.8%, 64.5% and 59.7% inhibition on the peroxidation of linoleic acid emulsion at the same concentration, respectively. In addition, p-coumaric acid had an effective DPPHrad scavenging, ABTSrad + scavenging, superoxide anion radical scavenging, hydrogen peroxide scavenging, ferric ions (Fe3+) reducing power and ferrous ions (Fe2+) chelating activities. Also, those various antioxidant activities were compared to BHA, BHT, α-tocopherol and ascorbic acid as references antioxidant compounds. These results suggested that p-coumaric acid can be used in the pharmacological and food industry because of these properties.
NASA Astrophysics Data System (ADS)
Chaudhary, Manchal; Shen, Po-fan; Chang, Sue-min
2018-05-01
Porous tungstated and phosphated TiO2-ZrO2 (TZ) binary oxides with high and strong acidity were successfully prepared by means of sol-gel or impregnation approaches. In addition, the influences of the two types of modifiers on the microstructures and acidity were systematically examined, compared, and clarified. The TZ oxide derived from a surfactant-templating method exhibited a high surface area of 195 m2/g with a pore size of 6.3 nm. Moreover, it had a high acidity of 859 μmol/g with a density of 4.4 μmol/nm2 because of defective surface. Phosphation significantly increased the acidity to 1547 μmol/g and showed the highest acid density of 6.7 μmol/nm2 at a surface P density of 22.7P/nm2. On the other hand, tungstated compounds just showed the highest acidity of 972 μmol/g and the highest acid density of 4.8 μmol/nm2 at 4.7 W/nm2. Compared to tungstate species, phosphate anions are more capable of promoting the acidity because they are able to distort the host network and inhibit elemental rearrangement. While Lewis acidity prevailed in the tungstated compounds, Brønsted acidity was dominant in the phosphated oxides. The Wdbnd O and Psbnd OH groups were responsible for strong acidity in the modified compounds. Phosphated compounds formed strong Brønsted acid sites on the Psbnd OH groups with a particular strength, and tungstation produced Lewis acid sites with a continuous strength on the metal ions adjacent to the tungstate moieties. Cyclic NH3 adsorption-desorption processes revealed that the active sites for NH3 adsorption were stable in both the tungstate and phosphate modified compounds, revealing that these solid acids are promising as the adsorbents for removal of base gases.
Inhibition of hepatic lipogenesis by 2-tetradecylglycidic acid.
McCune, S A; Nomura, T; Harris, R A
1979-10-01
2-Tetradecylglycidic acid (TDGA), a hypoglycemic agent, has been found to be a very effective inhibitor of de novo fatty acid synthesis by isolated hepatocytes. A comparison was made between the effectiveness of TDGA and 5-(tetradecyloxy)-2-furoic acid (TOFA), a hypolipidemic agent, on the metabolic processes of isolated hepatocytes. These compounds are structurally related and both inhibit fatty acid synthesis; however, they have opposite effects from each other on the oxidation and esterification of fatty acids. TDGA inhibits whereas TOFA stimulates fatty acid oxidation. TDGA stimulates whereas TOFA inhibits fatty acid esterification.
Process Research and Development of Antibodies as Countermeasures for C. Botulinum
2006-03-01
acid , lipoic acid , phenol red, putrescine 2HCl, sodium pyruvate, and HEPES is same as HAM’SF12:IMDM (1:1). The concentrations of the glucose...Na2SeO3 0.0085 D-glucose 4000 Linoleic Acid 0.04 Lipoic Acid 0.105 Phenol Red 8.1 Putrescine 2HCl 0.0805 Sodium Pyruvate 110 HEPES 2979 L-Alanine...0.0134 Arachidonic acid 0.014 cholestrol 1.54 DL- alpha -tocopherol- acetate 0.49 Linoleic acid 0.07 linolenic acid 0.07 myristic acid 0.07
Mohana, Marimuthu; Thomas Muthiah, Packianathan; McMillen, Colin D
2017-06-01
In solid-state engineering, cocrystallization is a strategy actively pursued for pharmaceuticals. Two 1:1 cocrystals of 5-fluorouracil (5FU; systematic name: 5-fluoro-1,3-dihydropyrimidine-2,4-dione), namely 5-fluorouracil-5-bromothiophene-2-carboxylic acid (1/1), C 5 H 3 BrO 2 S·C 4 H 3 FN 2 O 2 , (I), and 5-fluorouracil-thiophene-2-carboxylic acid (1/1), C 4 H 3 FN 2 O 2 ·C 5 H 4 O 2 S, (II), have been synthesized and characterized by single-crystal X-ray diffraction studies. In both cocrystals, carboxylic acid molecules are linked through an acid-acid R 2 2 (8) homosynthon (O-H...O) to form a carboxylic acid dimer and 5FU molecules are connected through two types of base pairs [homosynthon, R 2 2 (8) motif] via a pair of N-H...O hydrogen bonds. The crystal structures are further stabilized by C-H...O interactions in (II) and C-Br...O interactions in (I). In both crystal structures, π-π stacking and C-F...π interactions are also observed.
Rui, Liyun; Xie, Minhao; Hu, Bing; Zhou, Li; Saeeduddin, Muhammad; Zeng, Xiaoxiong
2017-08-15
Chlorogenic acid-chitosan conjugate was synthesized by introducing of chlorogenic acid onto chitosan with the aid of 1-ethyl-3-(3-dimethylaminopropyl) carbodiimide and hydroxybenzotriazole. The data of UV-vis, FT-IR and NMR for chlorogenic acid-chitosan conjugates demonstrated the successful conjugation of chlorogenic acid with chitosan. Compared to chitosan, chlorogenic acid-chitosan conjugates exhibited increased solubility in distilled water, 1% acetic acid solution (v/v) or 50% ethanol solution (v/v) containing 0.5% acetic acid. Moreover, chlorogenic acid-chitosan conjugates showed dramatic enhancements in metal ion chelating activity, total antioxidant capacity, scavenging activities on 2,2'-azino-bis-(3-ethylbenzothiazoline-6-sulphonic acid) and superoxide radicals, inhibitory effects on lipid peroxidation and β-carotene-linoleic acid bleaching, and protective effect on H 2 O 2 -induced oxidative injury of PC12 cells. Particularly, chlorogenic acid-chitosan conjugate exhibited higher inhibitory effects on lipid peroxidation and β-carotene-linoleic acid bleaching than chlorogenic acid. The results suggested that chlorogenic acid-chitosan conjugates could serve as food supplements to enhance the function of foods in future. Copyright © 2017 Elsevier Ltd. All rights reserved.
Effect of uric acid on inflammatory COX-2 and ROS pathways in vascular smooth muscle cells.
Oğuz, Nurgül; Kırça, Mustafa; Çetin, Arzu; Yeşilkaya, Akın
2017-10-01
Hyperuricemia is thought to play a role in cardiovascular diseases (CVD), including hypertension, coronary artery disease and atherosclerosis. However, exactly how uric acid contributes to these pathologies is unknown. An underlying mechanism of inflammatory diseases, such as atherosclerosis, includes enhanced production of cyclooxygenase-2 (COX-2) and superoxide anion. Here, we aimed to examine the effect of uric acid on inflammatory COX-2 and superoxide anion production and to determine the role of losartan. Primarily cultured vascular smooth muscle cells (VSMCs) were time and dose-dependently induced by uric acid and COX-2 and superoxide anion levels were measured. COX-2 levels were determined by ELISA, and superoxide anion was measured by the superoxide dismutase (SOD)-inhibitable reduction of ferricytochrome c method. Uric acid elevated COX-2 levels in a time-dependent manner. Angiotensin-II receptor blocker, losartan, diminished uric-acid-induced COX-2 elevation. Uric acid also increased superoxide anion level in VSMCs. Uric acid plays an important role in CVD pathogenesis by inducing inflammatory COX-2 and ROS pathways. This is the first study demonstrating losartan's ability to reduce uric-acid-induced COX-2 elevation.
Epoxy Pipelining Composition and Method of Manufacture.
1994-12-14
exemplary curing agent blend was prepared by reacting azelaic acid 3 (nonanedioic acid ), hexanoic acid , triethylene tetramine 4 (NH 2CH2CH2NHCH2CH2NHCH2CH...2NH2; TETA) and benzyl alcohol. The exemplary 5 curing agent blend was prepared as follows: 6 (a) Azelaic acid (solid; 90.9 gm.; 0.483 moles; C 9H 16 0...heated to 230 ’C over 10 - 20 11 minutes in a silicone oil bath. As the azelaic acid melted into a liquid, the 12 reaction mixture was stirred using a
21 CFR 184.1328 - Glyceryl behenate.
Code of Federal Regulations, 2010 CFR
2010-04-01
... glyceryl esters of behenic acid made from glycerin and behenic acid (a saturated C22 fatty acid). The... not more than 2.5 percent free fatty acids. (2) Behenic acid. Between 80 and 90 percent of the total fatty acid content. (3) Acid value. Not more than 4. (4) Saponification value. Between 145 and 165. (5...
21 CFR 184.1328 - Glyceryl behenate.
Code of Federal Regulations, 2011 CFR
2011-04-01
... glyceryl esters of behenic acid made from glycerin and behenic acid (a saturated C22 fatty acid). The... not more than 2.5 percent free fatty acids. (2) Behenic acid. Between 80 and 90 percent of the total fatty acid content. (3) Acid value. Not more than 4. (4) Saponification value. Between 145 and 165. (5...
Lee, Ho-Joo; Choi, Mun Hwan; Kim, Tae-Un; Yoon, Sung Chul
2001-01-01
A psychrotrophic bacterium, Pseudomonas fluorescens BM07, which is able to accumulate polyhydroxyalkanoic acid (PHA) containing large amounts of 3-hydroxy-cis-5-dodecenoate unit up to 35 mol% in the cell from unrelated substrates such as fructose, succinate, etc., was isolated from an activated sludge in a municipal wastewater treatment plant. When it was grown on heptanoic acid (C7) to hexadecanoic acid (C16) as the sole carbon source, the monomer compositional characteristics of the synthesized PHA were similar to those observed in other fluorescent pseudomonads belonging to rRNA homology group I. However, growth on stearic acid (C18) led to no PHA accumulation, but instead free stearic acid was stored in the cell. The existence of the linkage between fatty acid de novo synthesis and PHA synthesis was confirmed by using inhibitors such as acrylic acid and two other compounds, 2-bromooctanoic acid and 4-pentenoic acid, which are known to inhibit β-oxidation enzymes in animal cells. Acrylic acid completely inhibited PHA synthesis at a concentration of 4 mM in 40 mM octanoate-grown cells, but no inhibition of PHA synthesis occurred in 70 mM fructose-grown cells in the presence of 1 to 5 mM acrylic acid. 2-Bromooctanoic acid and 4-pentenoic acid were found to much inhibit PHA synthesis much more strongly in fructose-grown cells than in octanoate-grown cells over concentrations ranging from 1 to 5 mM. However, 2-bromooctanoic acid and 4-pentenoic acid did not inhibit cell growth at all in the fructose media. Especially, with the cells grown on fructose, 2-bromooctanoic acid exhibited a steep rise in the percent PHA synthesis inhibition over a small range of concentrations below 100 μM, a finding indicative of a very specific inhibition, whereas 4-pentenoic acid showed a broad, featureless concentration dependence, suggesting a rather nonspecific inhibition. The apparent inhibition constant Ki (the concentration for 50% inhibition of PHA synthesis) for 2-bromooctanoic acid was determined to be 60 μM, assuming a single-site binding of the inhibitor at a specific inhibition site. Thus, it seems likely that a coenzyme A thioester derivative of 2-bromooctanoic acid specifically inhibits an enzyme linking the two pathways, fatty acid de novo synthesis and PHA synthesis. We suggest that 2-bromooctanoic acid can substitute for the far more expensive (2,000 times) and cell-growth-inhibiting PHA synthesis inhibitor, cerulenin. PMID:11679314
Ionescu, Michael; Yokota, Kenji; Antonova, Elena; Garcia, Angelica; Beaulieu, Ellen; Hayes, Terry; Iavarone, Anthony T.
2016-01-01
ABSTRACT Cell density-dependent regulation of gene expression in Xylella fastidiosa that is crucial to its switching between plant hosts and insect vectors is dependent on RpfF and its production of 2-enoic acids known as diffusible signal factor (DSF). We show that X. fastidiosa produces a particularly large variety of similar, relatively long-chain-length 2-enoic acids that are active in modulating gene expression. Both X. fastidiosa itself and a Pantoea agglomerans surrogate host harboring X. fastidiosa RpfF (XfRpfF) is capable of producing a variety of both saturated and unsaturated free fatty acids. However, only 2-cis unsaturated acids were found to be biologically active in X. fastidiosa. X. fastidiosa produces, and is particularly responsive to, a novel DSF species, 2-cis-hexadecanoic acid that we term XfDSF2. It is also responsive to other, even longer 2-enoic acids to which other taxa such as Xanthomonas campestris are unresponsive. The 2-enoic acids that are produced by X. fastidiosa are strongly affected by the cellular growth environment, with XfDSF2 not detected in culture media in which 2-tetradecenoic acid (XfDSF1) had previously been found. X. fastidiosa is responsive to much lower concentrations of XfDSF2 than XfDSF1. Apparently competitive interactions can occur between various saturated and unsaturated fatty acids that block the function of those agonistic 2-enoic fatty acids. By altering the particular 2-enoic acids produced and the relative balance of free enoic and saturated fatty acids, X. fastidiosa might modulate the extent of DSF-mediated quorum sensing. PMID:27435463
Weerachayaphorn, Jittima; Mennone, Albert; Soroka, Carol J.; Harry, Kathy; Hagey, Lee R.; Kensler, Thomas W.
2012-01-01
The transcription factor nuclear factor-E2-related factor 2 (Nrf2) is a key regulator for induction of hepatic detoxification and antioxidant mechanisms, as well as for certain hepatobiliary transporters. To examine the role of Nrf2 in bile acid homeostasis and cholestasis, we assessed the determinants of bile secretion and bile acid synthesis and transport before and after bile duct ligation (BDL) in Nrf2−/− mice. Our findings indicate reduced rates of biliary bile acid and GSH excretion, higher levels of intrahepatic bile acids, and decreased expression of regulators of bile acid synthesis, Cyp7a1 and Cyp8b1, in Nrf2−/− compared with wild-type control mice. The mRNA expression of the bile acid transporters bile salt export pump (Bsep) and organic solute transporter (Ostα) were increased in the face of impaired expression of the multidrug resistance-associated proteins Mrp3 and Mrp4. Deletion of Nrf2 also decreased ileal apical sodium-dependent bile acid transporter (Asbt) expression, leading to reduced bile acid reabsorption and increased loss of bile acid in feces. Finally, when cholestasis is induced by BDL, liver injury was not different from that in wild-type BDL mice. These Nrf2−/− mice also had increased pregnane X receptor (Pxr) and Cyp3a11 mRNA expression in association with enhanced hepatic bile acid hydroxylation. In conclusion, this study finds that Nrf2 plays a major role in the regulation of bile acid homeostasis in the liver and intestine. Deletion of Nrf2 results in a cholestatic phenotype but does not augment liver injury following BDL. PMID:22345550
Sivanathan, Sivatharushan; Körber, Florian; Tent, Jannis Aron; Werner, Svenja; Scherkenbeck, Jürgen
2015-03-06
Phenyllactic acids are found in numerous natural products as well as in active substances used in medicine or plant protection. Enantiomerically pure phenyllactic acids are available by transition-metal-catalyzed hydrogenations or chemoenzymatic reductions of the corresponding 3-aryl-2-oxopropanoic acids. We show here that d-lactate dehydrogenase from Staphylococcus epidermidis reduces a broad spectrum of 2-oxo acids, which are difficult substrates for transition-metal-catalyzed reactions, with excellent enantioselectivities in a simple experimental setup.
Response of soybean seed germination to cadmium and acid rain.
Liu, Ting Ting; Wu, Peng; Wang, Li Hong; Zhou, Qing
2011-12-01
Cadmium (Cd) pollution and acid rain are the main environmental issues, and they often occur in the same agricultural region. Nevertheless, up to now, little information on the combined pollution of Cd(2+) and acid rain action on crops were presented. Here, we investigated the combined effect of Cd(2+) and acid rain on the seed germination of soybean. The results indicated that the single treatment with the low level of Cd(2+) (0.18, 1.0, 3.0 mg L(-1)) or acid rain (pH ≥3.0) could not affect the seed germination of soybean, which was resulted in the increased activities of peroxidase and catalase. The single treatment with the high concentration of Cd(2+) (>6 mg L(-1)) or acid rain at pH 2.5 decreased the activities of peroxidase and catalase, damaged the cell membrane and then decreased the seed germination of soybean. Meanwhile, the same toxic effect was observed in the combined treatment with Cd(2+) and acid rain, and the combined treatment had more toxic effect than the single treatment with Cd(2+) or acid rain. Thus, the combined pollution of Cd(2+) and acid rain had more potential threat to the seed germination of soybean than the single pollution of Cd(2+) or acid rain.
NASA Astrophysics Data System (ADS)
Xing, Peiqi; Li, Qingyun; Li, Yingying; Wang, Kunpeng; Zhang, Qi; Wang, Lei
2017-05-01
By using solvent evaporation method, 2,4,6-triaminopyrimidine (TAPI) is employed to crystallize with a variety of acids, including 3,5-dihydroxybenzoic acid (HDHBA), 3-nitrophthalic acid (H2NPA), 5-amino-2,4,6-triiodoisophthalic acid (H2ATIPIA), 2,5-dibromoterephthalic acid (H2DBTPA), 1,5-naphthalenedisulfonic acid (H2NDSA), sebacic acid (H2SA), 1,2,4-benzenetricarboxylic acid (H3BTA), and biphenyl-2,2‧,5,5'-tetracarboxylic acid (H4BPTA). In all eight complexes, protons are completely exchanged from O atom of acid to nitrogen of TAPI in 1, 3, 4, and, 5, partly transferred in 2, 6, 7, and 8. The crystal structure of all eight complexes exhibit that classical robust hydrogen bonds X-H⋯X (X = O/N) direct the molecular crystals to bind together in a stacking modes. Classical hydrogen bond Nsbnd H⋯O is participated in forming all eight organic salts, while hydrogen bonding Osbnd H⋯O are found in constructing the diversity structures in salts 1, 2, 3, 4, 6, and 7. The analysis shows that some classical supramolecular synthons, such as I R22(8), V R24(12), and VI S(6), are observed again in the construction of hydrogen-bonding networks. In the formation of layered and reticular structure, strong hydrogen bonds between water molecules and ligands having well-refined hydrogen atoms have been considered. Water molecules play an important role in building supramolecular structures of 1, 2, 3, 4, 7, and 8. Moreover, salts 1-8 are further characterized and analyzed by element analysis, infrared radiation, thermogravimetric analysis, proton nuclear magnetic resonance spectra, and mass spectra.
Code of Federal Regulations, 2014 CFR
2014-07-01
... 40 Protection of Environment 31 2014-07-01 2014-07-01 false 1,2-Benzenedicarboxylic acid, mixed... Substances § 721.10457 1,2-Benzenedicarboxylic acid, mixed esters with benzyl alc., cyclohexanol, 2-ethyl-1... reporting. (1) The chemical substance identified as 1,2-benzenedicarboxylic acid, mixed esters with benzyl...
Code of Federal Regulations, 2013 CFR
2013-07-01
... 40 Protection of Environment 32 2013-07-01 2013-07-01 false 1,2-Benzenedicarboxylic acid, mixed... Substances § 721.10457 1,2-Benzenedicarboxylic acid, mixed esters with benzyl alc., cyclohexanol, 2-ethyl-1... reporting. (1) The chemical substance identified as 1,2-benzenedicarboxylic acid, mixed esters with benzyl...
2-Alkynoic fatty acids inhibit topoisomerase IB from Leishmania donovani.
Carballeira, Néstor M; Cartagena, Michelle; Sanabria, David; Tasdemir, Deniz; Prada, Christopher F; Reguera, Rosa M; Balaña-Fouce, Rafael
2012-10-01
2-Alkynoic fatty acids display antimycobacterial, antifungal, and pesticidal activities but their antiprotozoal activity has received little attention. In this work we synthesized the 2-octadecynoic acid (2-ODA), 2-hexadecynoic acid (2-HDA), and 2-tetradecynoic acid (2-TDA) and show that 2-ODA is the best inhibitor of the Leishmania donovani DNA topoisomerase IB enzyme (LdTopIB) with an EC(50)=5.3±0.7μM. The potency of LdTopIB inhibition follows the trend 2-ODA>2-HDA>2-TDA, indicating that the effectiveness of inhibition depends on the fatty acid carbon chain length. All of the studied 2-alkynoic fatty acids were less potent inhibitors of the human topoisomerase IB enzyme (hTopIB) as compared to LdTopIB. 2-ODA also displayed in vitro activity against Leishmania donovani (IC(50)=11.0μM), but it was less effective against other protozoa, Trypanosoma cruzi (IC(50)=48.1μM) and Trypanosoma brucei rhodesiense (IC(50)=64.5μM). The antiprotozoal activity of the 2-alkynoic fatty acids, in general, followed the trend 2-ODA>2-HDA>2-TDA. The experimental information gathered so far indicates that 2-ODA is a promising antileishmanial compound. Copyright © 2012 Elsevier Ltd. All rights reserved.
Koide, M; Okahashi, N; Tanaka, R; Kazuno, K; Shibasaki, K; Yamazaki, Y; Kaneko, K; Ueda, N; Ohguchi, M; Ishihara, Y; Noguchi, T; Nishihara, T
1999-09-01
It is known that bone resorption is mediated by osteoclasts, and lipopolysaccharide (LPS) and inflammatory mediators such as interleukin-1 (IL-1) and prostaglandin E2 (PGE2) induce osteoclast differentiation from haemopoietic cells, 2-aminoethanesulphonic acid, which is known as taurine, is an important nutrient and is added to most synthetic human infant milk formulas. In this study, it was found that 2-aminoethanesulphonic acid inhibits the stimulation of bone resorption mediated by LPS of the periodontopathic microorganism Actinobacillus actinomycetemcomitans Y4 in organ cultures of newborn mouse calvaria. The effect of 2-aminoethanesulphonic acid on the development and survival of osteoclast-like multinucleated cells produced in a mouse bone-marrow culture system was also examined. 2-aminoethanesulphonic acid (100 microg/ml) suppressed the formation of these osteoclast-like cells in the presence of LPS of A. actinomycetemcomitans Y4, IL-1alpha or PGE2 in mouse marrow cultures. On the other hand, 2-aminoethanesulphonic acid did not inhibit 1alpha, 25-dihydroxyvitamin D3-mediated osteoclast differentiation. Although IL-1alpha elongated the survival of the osteoclast-like cells, 2-aminoethanesulphonic acid blocked the supportive effect of IL-1alpha on osteoclast survival. 2-aminoethanesulphonic acid showed no effect on the growth of mouse osteoblasts. Finally, it was found that 2-aminoethanesulphonic acid inhibited alveolar bone resorption in experimental periodontitis in hamsters. These results suggest that 2-aminoethanesulphonic acid is an effective agent in preventing inflammatory bone resorption in periodontal diseases.
Fatty acid constituents of Peganum harmala plant using Gas Chromatography-Mass Spectroscopy.
Moussa, Tarek A A; Almaghrabi, Omar A
2016-05-01
Fatty acid contents of the Peganum harmala plant as a result of hexane extraction were analyzed using GC-MS. The saturated fatty acid composition of the harmal plant was tetradecanoic, pentadecanoic, tridecanoic, hexadecanoic, heptadecanoic and octadecanoic acids, while the saturated fatty acid derivatives were 12-methyl tetradecanoic, 5,9,13-trimethyl tetradecanoic and 2-methyl octadecanoic acids. The most abundant fatty acid was hexadecanoic with concentration 48.13% followed by octadecanoic with concentration 13.80%. There are four unsaturated fatty acids called (E)-9-dodecenoic, (Z)-9-hexadecenoic, (Z,Z)-9,12-octadecadienoic and (Z,Z,Z)-9,12,15-octadecatrienoic. The most abundant unsaturated fatty acid was (Z,Z,Z)-9,12,15-octadecatrienoic with concentration 14.79% followed by (Z,Z)-9,12-octadecadienoic with concentration 10.61%. Also, there are eight non-fatty acid compounds 1-octadecene, 6,10,14-trimethyl-2-pentadecanone, (E)-15-heptadecenal, oxacyclohexadecan-2 one, 1,2,2,6,8-pentamethyl-7-oxabicyclo[4.3.1]dec-8-en-10-one, hexadecane-1,2-diol, n-heneicosane and eicosan-3-ol.
Fatty acid constituents of Peganum harmala plant using Gas Chromatography–Mass Spectroscopy
Moussa, Tarek A.A.; Almaghrabi, Omar A.
2015-01-01
Fatty acid contents of the Peganum harmala plant as a result of hexane extraction were analyzed using GC–MS. The saturated fatty acid composition of the harmal plant was tetradecanoic, pentadecanoic, tridecanoic, hexadecanoic, heptadecanoic and octadecanoic acids, while the saturated fatty acid derivatives were 12-methyl tetradecanoic, 5,9,13-trimethyl tetradecanoic and 2-methyl octadecanoic acids. The most abundant fatty acid was hexadecanoic with concentration 48.13% followed by octadecanoic with concentration 13.80%. There are four unsaturated fatty acids called (E)-9-dodecenoic, (Z)-9-hexadecenoic, (Z,Z)-9,12-octadecadienoic and (Z,Z,Z)-9,12,15-octadecatrienoic. The most abundant unsaturated fatty acid was (Z,Z,Z)-9,12,15-octadecatrienoic with concentration 14.79% followed by (Z,Z)-9,12-octadecadienoic with concentration 10.61%. Also, there are eight non-fatty acid compounds 1-octadecene, 6,10,14-trimethyl-2-pentadecanone, (E)-15-heptadecenal, oxacyclohexadecan-2 one, 1,2,2,6,8-pentamethyl-7-oxabicyclo[4.3.1]dec-8-en-10-one, hexadecane-1,2-diol, n-heneicosane and eicosan-3-ol. PMID:27081366
Code of Federal Regulations, 2013 CFR
2013-07-01
... 40 Protection of Environment 32 2013-07-01 2013-07-01 false 2-Propenoic acid, 2-methyl-, 1,1â²-[2... SUBSTANCES Significant New Uses for Specific Chemical Substances § 721.10122 2-Propenoic acid, 2-methyl-, 1,1... new uses subject to reporting. (1) The chemical substance identified as 2-propenoic acid, 2-methyl-, 1...
Code of Federal Regulations, 2012 CFR
2012-07-01
... 40 Protection of Environment 32 2012-07-01 2012-07-01 false 2-Propenoic acid, 2-methyl-, 1,1â²-[2... SUBSTANCES Significant New Uses for Specific Chemical Substances § 721.10122 2-Propenoic acid, 2-methyl-, 1,1... new uses subject to reporting. (1) The chemical substance identified as 2-propenoic acid, 2-methyl-, 1...
Code of Federal Regulations, 2014 CFR
2014-07-01
... 40 Protection of Environment 31 2014-07-01 2014-07-01 false 2-Propenoic acid, 2-methyl-, 1,1â²-[2... SUBSTANCES Significant New Uses for Specific Chemical Substances § 721.10122 2-Propenoic acid, 2-methyl-, 1,1... new uses subject to reporting. (1) The chemical substance identified as 2-propenoic acid, 2-methyl-, 1...
Fischer, Klaus; Bipp, Hans-Peter
2005-05-01
Carbohydrate-rich biomass residues, i.e. sugar beet molasses, whey powder, wine yeast, potato peel sludge, spent hops, malt dust and apple marc, were tested as starting materials for the generation of marketable chemicals, e.g. aliphatic acids, sugar acids and mono-/disaccharides. Residues were oxidized or hydrolyzed under acidic or alkaline conditions applying conventional laboratory digestion methods and microwave assisted techniques. Yields and compositions of the oxidation products differed according to the oxidizing agent used. Main products of oxidation by 30% HNO(3) were acetic, glucaric, oxalic and glycolic acids. Applying H(2)O(2)/CuO in alkaline solution, the organic acid yields were remarkably lower with formic, acetic and threonic acids as main products. Gluconic acid was formed instead of glucaric acid throughout. Reaction of a 10% H(2)O(2) solution with sugar beet molasses generated formic and lactic acids mainly. Na(2)S(2)O(8) solutions were very inefficient at oxidizing the residues. Glucose, arabinose and galactose were formed during acidic hydrolysis of malt dust and apple marc. The glucose content reached 0.35 g per gram of residue. Important advantages of the microwave application were lower reaction times and reduced reagent demands.
Mlakar, A; Spiteller, G
1997-01-01
2-Hydroxy-succinaldehyde was detected by a GC/MS analysis of trapped aldehydic compounds obtained after Fe2+/ascorbate lipid peroxidation of arachidonic acid. Precursor molecules of aldehydes are hydroperoxy compounds. Thus the generation of the two aldehydic groups in 2-hydroxysuccinaldehyde requires a precursor molecule with two hydroperoxy groups. The hydroxy group in 2-position is generated by a third hydroperoxidation reaction. The detection of 2-hydroxysuccinaldehyde--although found only in traces--is the first example for triple dioxigenation of unsaturated fatty acid. Linolenic acid produces 2-hydroxysuccinaldehyde in much lower amounts than arachidonic acid. A similar oxidation of linoleic acid was not observed.
Ding, Xuemei; Lin, Shuhai; Weng, Hongbo; Liang, Jianying
2018-06-01
Lactic acid and 2-hydroxyglutaric acid are chiral metabolites that have two distinct d- and l-enantiomers with distinct biochemical properties. Perturbations of a single enantiomeric form have been found to be closely related to certain diseases. Therefore, the ability to differentiate the d and l enantiomers is important for these disease studies. Herein, we describe a method for the separation and determination of lactic acid and 2-hydroxyglutaric acid enantiomers by chiral derivatization (with l-menthol and acetyl chloride) combined with gas chromatography and mass spectrometry. The two pairs of above-mentioned enantiomers exhibited linear calibration curves with a correlation coefficient (R 2 ) exceeding 0.99. The measured data were accurate in the acceptable recovery range of 88.17-102.30% with inter- and intraday precisions (relative standard deviations) in the range of 4.23-17.26%. The limits of detection for d-lactic acid, l-lactic acid, d-2-hydroxyglutaric acid, and l-2-hydroxyglutaric acid were 0.13, 0.11, 1.12, and 1.16 μM, respectively. This method was successfully applied to analyze mouse plasma. The d-lactic acid levels in type 2 diabetes mellitus mouse plasma were observed to be significantly higher (P < 0.05, t-test) than those of normal mice, suggesting that d-lactic acid may serve as an indicator for type 2 diabetes mellitus. © 2018 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.
Analysis of Chemical Signatures of Alkaliphiles using Fatty Acid Methyl Ester Analysis
Sreenivasulu, Basha; Paramageetham, Chinthala; Sreenivasulu, Dasari; Suman, Bukke; Umamahesh, Katike; Babu, Gundala Prasada
2017-01-01
Background: Fatty acids occur in nearly all living organisms as the important predominant constituents of lipids. While all fatty acids have essentially the same chemical nature, they are an extremely diverse group of compounds. Materials and Methods: To test the hypothesis, fatty acids of alkaliphiles isolates, Bacillus subtilis SVUNM4, Bacillus licheniformis SVUNM8, Bacillus methylotrohicus SVUNM9, and Paenibacillus dendritiformis SVUNM11, were characterized compared using gas chromatography-mass spectrometry (GC-MS) analysis. Results: The content of investigated ten fatty acids, 1, 2-benzenedicarboxylic acid butyl 2-methylpropyl ester, phthalic acid, isobutyl 2-pentyl ester, dibutyl phthalate, cyclotrisiloxane, hexamethyl, cyclotetrasiloxane, octamethyl, dodecamethyl, heptasiloxane 1,1,3,3,5,5,7,7,9,9,11,11,13,13-etradecamethyl, 7,15-dihydroxydehydroabietic acid, methyl ester, di (trimethylsilyl) ether, hentriacontane, 2-thiopheneacetic acid, undec-2-enyl ester, obviously varied among four species, suggesting each species has its own fatty acid pattern. Conclusions: These findings demonstrated that GC-MS-based fatty acid profiling analysis provides the reliable platform to classify these four species, which is helpful for ensuring their biotechnological interest and novel chemotaxonomic. PMID:28717333
Seo, Jong-Su; Keum, Young-Soo; Hu, Yuting; Lee, Sung-Eun; Li, Qing X
2007-02-01
Burkholderia sp. C3 was isolated from a polycyclic aromatic hydrocarbon (PAH)-contaminated site in Hilo, Hawaii, USA, and studied for its degradation of phenanthrene as a sole carbon source. The initial 3,4-C dioxygenation was faster than 1,2-C dioxygenation in the first 3-day culture. However, 1-hydroxy-2-naphthoic acid derived from 3,4-C dioxygenation degraded much slower than 2-hydroxy-1-naphthoic acid derived from 1,2-C dioxygenation. Slow degradation of 1-hydroxy-2-naphthoic acid relative to 2-hydroxy-1-naphthoic acid may trigger 1,2-C dioxygenation faster after 3 days of culture. High concentrations of 5,6- and 7,8-benzocoumarins indicated that meta-cleavage was the major degradation mechanism of phenanthrene-1,2- and -3,4-diols. Separate cultures with 2-hydroxy-1-naphthoic acid and 1-hydroxy-2-naphthoic acid showed that the degradation rate of the former to naphthalene-1,2-diol was much faster than that of the latter. The two upper metabolic pathways of phenanthrene are converged into naphthalene-1,2-diol that is further metabolized to 2-carboxycinnamic acid and 2-hydroxybenzalpyruvic acid by ortho- and meta-cleavages, respectively. Transformation of naphthalene-1,2-diol to 2-carboxycinnamic acid by this strain represents the first observation of ortho-cleavage of two rings-PAH-diols by a Gram-negative species.
Sen, Suranjana; Sirobhushanam, Sirisha; Hantak, Michael P; Lawrence, Peter; Brenna, J Thomas; Gatto, Craig; Wilkinson, Brian J
2015-10-01
Listeria monocytogenes is a psychrotolerant food borne pathogen, responsible for the high fatality disease listeriosis, and expensive food product recalls. Branched-chain fatty acids (BCFAs) of the membrane play a critical role in providing appropriate membrane fluidity and optimum membrane biophysics. The fatty acid composition of a BCFA-deficient mutant is characterized by high amounts of straight-chain fatty acids and even-numbered iso fatty acids, in contrast to the parent strain where odd-numbered anteiso fatty acids predominate. The presence of 2-methylbutyrate (C5) stimulated growth of the mutant at 37°C and restored growth at 10°C along with the content of odd-numbered anteiso fatty acids. The C6 branched-chain carboxylic acids 2-ethylbutyrate and 2-methylpentanoate also stimulated growth to a similar extent as 2-methylbutyrate. However, 3-methylpentanoate was ineffective in rescuing growth. 2-Ethylbutyrate and 2-methylpentanoate led to novel major fatty acids in the lipid profile of the membrane that were identified as 12-ethyltetradecanoic acid and 12-methylpentadecanoic acid respectively. Membrane anisotropy studies indicated that growth of strain MOR401 in the presence of these precursors increased its membrane fluidity to levels of the wild type. Cells supplemented with 2-methylpentanoate or 2-ethylbutyrate at 10°C shortened the chain length of novel fatty acids, thus showing homeoviscous adaptation. These experiments use the mutant as a tool to modulate the membrane fatty acid compositions through synthetic precursor supplementation, and show how existing enzymes in L. monocytogenes adapt to exhibit non-native activity yielding unique 'unnatural' fatty acid molecules, which nevertheless possess the correct biophysical properties for proper membrane function in the BCFA-deficient mutant. Copyright © 2015 Elsevier B.V. All rights reserved.
Kang, Nam Joo; Lee, Ki Won; Shin, Bong Jik; Jung, Sung Keun; Hwang, Mun Kyung; Bode, Ann M.; Heo, Yong-Seok; Dong, Zigang
2009-01-01
Caffeic acid (3,4-dihydroxycinnamic acid) is a well-known phenolic phytochemical present in many foods, including coffee. Recent studies suggested that caffeic acid exerts anticarcinogenic effects, but little is known about the underlying molecular mechanisms and specific target proteins. In this study, we found that Fyn, one of the members of the non-receptor protein tyrosine kinase family, was required for ultraviolet (UV) B-induced cyclooxygenase-2 (COX-2) expression, and caffeic acid suppressed UVB-induced skin carcinogenesis by directly inhibiting Fyn kinase activity. Caffeic acid more effectively suppressed UVB-induced COX-2 expression and subsequent prostaglandin E2 production in JB6 P+ mouse skin epidermal (JB6 P+) cells compared with chlorogenic acid (5-O-caffeoylquinic acid), an ester of caffeic acid with quinic acid. Data also revealed that caffeic acid more effectively induced the downregulation of COX-2 expression at the transcriptional level mediated through the inhibition of activator protein-1 (AP-1) and nuclear factor-κB transcription activity compared with chlorogenic acid. Fyn kinase activity was suppressed more effectively by caffeic acid than by chlorogenic acid, and downstream mitogen-activated protein kinases (MAPKs) were subsequently blocked. Pharmacological Fyn kinase inhibitor (3-(4-chlorophenyl)1-(1,1-dimethylethyl)-1H-pyrazolo[3,4-d]pyrimidin-4-amine and leflunomide) data also revealed that Fyn is involved in UVB-induced COX-2 expression mediated through the phosphorylation of MAPKs in JB6 P+ cells. Pull-down assays revealed that caffeic acid directly bound with Fyn and non-competitively with adenosine triphosphate. In vivo data from mouse skin also supported the idea that caffeic acid suppressed UVB-induced COX-2 expression by blocking Fyn kinase activity. These results suggested that this compound could act as a potent chemopreventive agent against skin cancer. PMID:19073879
Glutamic Acid – the Main Dietary Amino Acid – and Blood Pressure: The INTERMAP Study
Stamler, Jeremiah; Brown, Ian J; Daviglus, Martha L; Chan, Queenie; Kesteloot, Hugo; Ueshima, Hirotsugu; Zhao, Liancheng; Elliott, Paul
2009-01-01
Background Data are available indicating an independent inverse relationship of dietary vegetable protein to the blood pressure (BP) of individuals. Here we assess whether BP is associated with glutamic acid intake (the predominant dietary amino acid, especially in vegetable protein) and with each of four other amino acids higher relatively in vegetable than animal protein (proline, phenylalanine, serine, cystine). Methods and Results Cross-sectional epidemiological study; 4,680 persons ages 40–59 -- 17 random population samples in China, Japan, U.K., U.S.A.; BP measurement 8 times at 4 visits; dietary data (83 nutrients, 18 amino acids) from 4 standardized multi-pass 24-hour dietary recalls and 2 timed 24-hour urine collections. Dietary glutamic acid (percent of total protein intake) was inversely related to BP. Across multivariate regression models (Model 1 controlled for age, gender, sample, through Model 5 controlled for 16 non-nutrient and nutrient possible confounders) estimated average BP differences associated with glutamic acid intake higher by 4.72% total dietary protein (2 s.d.) were −1.5 to −3.0 mm Hg systolic and −1.0 to −1.6 mm Hg diastolic (Z-values −2.15 to −5.11). Results were similar for the glutamic acid-BP relationship with each other amino acid also in the model, e.g., with control for 15 variables plus proline, systolic/diastolic pressure differences −2.7/−2.0 (Z −2.51, −2.82). In these 2-amino acid models, higher intake (2 s.d.) of each other amino acid was associated with small BP differences and Z-values. Conclusions Dietary glutamic acid may have independent BP lowering effects, possibly contributing to the inverse relation of vegetable protein to BP. PMID:19581495
Sireesha, Pedaballi; Sun, Wei-Gang; Su, Chaochin; Kathirvel, Sasipriya; Lekphet, Woranan; Akula, Suri Babu; Li, Wen-Ri
2017-01-01
The surface modification of the TiO2 photoelectrode film is one of the promising ways to improve the photovoltaic performance of dye-sensitized solar cell (DSSC). In this work for the acid treatment of TiO2 powder, fluorine containing compounds such as trifluoroacetic acid was carried out to enhance the properties of photoanode. In order to investigate the effect of trifluoroacetyl group, the TiO2 nanopowders were also treated with different acids such as acetic acid, nitric acid, hydrochloric acid, and sulfuric acid and their properties were compared. The TiO2 powders treated with both acetic acid and TFA have possessed smooth surface morphologies as well as enhanced particle dispersions with reduced particle sizes. Photoelectrodes prepared for these two kinds of TiO2 powders accommodated high amounts of dye loading and exhibited excellent light transmittance (wavelength region of 400–600 nm). Electrochemical impedance spectroscopy analysis showed the smallest radius of the semicircle which indicates the enhanced rate of electron transport for the cell based photoelectrode with trifluoroacetic acid treated TiO2 powder. The solar cell from the untreated TiO2 film showed the power conversion efficiency of 8.86% and the highest efficiency of 9.51% was achieved by the cell fabricated from trifluoroacetic acid treated TiO2 film.
Anoxic and oxic removal of humic acids with Fe@Fe2O3 core-shell nanowires: a comparative study.
Wu, Hao; Ai, Zhihui; Zhang, Lizhi
2014-04-01
In this study we comparatively investigate the removal of humic acids with Fe@Fe2O3 core-shell nanowires under anoxic and oxic conditions. The products of humic acids after reacting with Fe@Fe2O3 core-shell nanowires under anoxic and oxic conditions were carefully examined with three-dimensional excitation emission matrix fluorescence spectroscopy and gas chromatography mass spectrometry. It was found that humic acids were removed by Fe@Fe2O3 core-shell nanowires via adsorption under anoxic condition. Langmuir adsorption isotherm was applicable to describe the adsorption processes. Kinetics of humic acids adsorption onto Fe@Fe2O3 core-shell nanowires was found to follow pseudo-second-order rate equation. By contrast, the oxic removal of humic acids with Fe@Fe2O3 core-shell nanowires involved adsorption and subsequent oxidation of humic acids because Fe@Fe2O3 core-shell nanowires could activate molecular oxygen to produce reactive oxygen species to oxidize humic acids. This subsequent oxidation of humic acids could improve the oxic removal rate to 2.5 times that of anoxic removal, accompanying with about 8.4% of mineralization. This study provides a new method for humic acids removal and also sheds light on the effects of humic acids on the pollutant removal by nano zero-valent iron. Copyright © 2014 Elsevier Ltd. All rights reserved.
Code of Federal Regulations, 2011 CFR
2011-07-01
... 40 Protection of Environment 31 2011-07-01 2011-07-01 false Benzoic acid, 5-amino-2-chloro-, 1,1... SUBSTANCES Significant New Uses for Specific Chemical Substances § 721.10020 Benzoic acid, 5-amino-2-chloro... subject to reporting. (1) The chemical substance identified as benzoic acid, 5-amino-2-chloro-, 1,1...
Code of Federal Regulations, 2010 CFR
2010-07-01
... 40 Protection of Environment 30 2010-07-01 2010-07-01 false Benzoic acid, 5-amino-2-chloro-, 1,1... SUBSTANCES Significant New Uses for Specific Chemical Substances § 721.10020 Benzoic acid, 5-amino-2-chloro... subject to reporting. (1) The chemical substance identified as benzoic acid, 5-amino-2-chloro-, 1,1...
Water-enhanced solvation of organics
DOE Office of Scientific and Technical Information (OSTI.GOV)
Lee, Jane H.
1993-07-01
Water-enhanced solvation (WES) was explored for Lewis acid solutes in Lewis base organic solvents, to develop cheap extract regeneration processes. WES for solid solutes was determined from ratios of solubilities of solutes in water-sat. and low-water solvent; both were determined from solid-liquid equilibrium. Vapor-headspace analysis was used to determine solute activity coefficients as function of organic phase water concentration. WES magnitudes of volatile solutes were normalized, set equal to slope of log γ s vs x w/x s curve. From graph shape Δ(log γ s) represents relative change in solute activity coefficient. Solutes investigated by vapor-headspace analysis were acetic acid,more » propionic acid, ethanol, 1,2-propylene glycol, 2,3-butylene glycol. Monocarboxylic acids had largest decrease in activity coefficient with water addition followed by glycols and alcohols. Propionic acid in cyclohexanone showed greatest water-enhancement Δ(log γ acid)/Δ(x w/x acid) = -0.25. In methylcyclohexanone, the decrease of the activity coefficient of propionic acid was -0.19. Activity coefficient of propionic acid in methylcyclohexanone stopped decreasing once the water reached a 2:1 water to acid mole ratio, implying a stoichiometric relation between water, ketone, and acid. Except for 2,3-butanediol, activity coefficients of the solutes studied decreased monotonically with water content. Activity coefficient curves of ethanol, 1,2-propanediol and 2,3-butanediol did not level off at large water/solute mole ratio. Solutes investigated by solid-liquid equilibrium were citric acid, gallic acid, phenol, xylenols, 2-naphthol. Saturation concentration of citric acid in anhydrous butyl acetate increased from 0.0009 to 0.087 mol/L after 1.3 % (g/g) water co-dissolved into organic phase. Effect of water-enhanced solvation for citric acid is very large but very small for phenol and its derivatives.« less
Prostaglandin E(2) mediates acid-induced heartburn in healthy volunteers.
Kondo, Takashi; Oshima, Tadayuki; Tomita, Toshihiko; Fukui, Hirokazu; Watari, Jiro; Okada, Hiroki; Kikuchi, Shojiro; Sasako, Mitsuru; Matsumoto, Takayuki; Knowles, Charles H; Miwa, Hiroto
2013-03-15
Prostaglandin E(2) (PGE(2)) plays a major role in pain processing and hypersensitivity. This study investigated whether PGE(2) levels are increased in the esophageal mucosa after acid infusion and whether increases in PGE(2) are associated with heartburn. Furthermore, expression of the PGE(2) receptor EP1 was investigated in human esophageal mucosa. Fourteen healthy male volunteers were randomized to 30-min lower esophageal acid (1% HCl) or saline perfusion. Before and after acid perfusion, endoscopic biopsies were taken from the distal esophagus. PGE(2) concentration (pg/mg protein) and EP1 mRNA and protein in biopsy samples were measured by ELISA, RT-PCR, and Western blotting. Symptom status of heartburn was evaluated with a validated categorical rating scale with a higher values corresponding to increasing intensity. PGE(2) levels in the esophageal mucosa significantly increased after acid infusion (before vs. after acid infusion: 23.2 ± 8.6 vs. 68.6 ± 18.3, P < 0.05), but not after saline infusion (before vs. after saline infusion: 9.3 ± 2.5 vs. 9.0 ± 3.2, NS). Time to first sensation (min) after acid infusion was less than after saline (saline vs. acid infusion: 22.1 ± 4.1 vs. 5.4 ± 1.5, P < 0.05). Intensity of heartburn in the acid-infusion group was also significantly greater compared with saline (saline vs. acid infusion: 54.3 ± 13.1 vs. 178.5 ± 22.8, P < 0.01). Changes in PGE(2) levels in the esophagus correlated with symptom intensity score (r = 0.80, P = 0.029). EP1 mRNA and protein expression were observed in the normal human esophageal mucosa. Esophageal PGE(2) expression is associated with mucosal acid exposure and heartburn.
Takebayashi, Jun; Tai, Akihiro; Gohda, Eiichi; Yamamoto, Itaru
2006-04-01
The aim of this study was to characterize the antioxidant activity of three ascorbic acid (AA) derivatives O-substituted at the C-2 position of AA: ascorbic acid 2-glucoside (AA-2G), ascorbic acid 2-phosphate (AA-2P), and ascorbic acid 2-sulfate (AA-2S). The radical-scavenging activities of these AA derivatives and some common low molecular-weight antioxidants such as uric acid or glutathione against 1,1-diphenyl-picrylhydrazyl (DPPH) radical, 2,2'-azinobis(3-ethylbenzothiazoline-6-sulfonic acid) radical cation (ABTS+), or galvinoxyl radical were kinetically and stoichiometrically evaluated under pH-controlled conditions. Those AA derivatives slowly and continuously reacted with DPPH radical and ABTS+, but not with galvinoxyl radical. They effectively reacted with DPPH radical under acidic conditions and with ABTS+ under neutral conditions. In contrast, AA immediately quenched all species of radicals tested at all pH values investigated. The reactivity of Trolox, a water-soluble vitamin E analogue, was comparable to that of AA in terms of kinetics and stoichiometrics. Uric acid and glutathione exhibited long-lasting radical-scavenging activity against these radicals under certain pH conditions. The radical-scavenging profiles of AA derivatives were closer to those of uric acid and glutathione rather than to that of AA. The number of radicals scavenged by one molecule of AA derivatives, uric acid, or glutathione was equal to or greater than that by AA or Trolox under the appropriate conditions. These data suggest the potential usage of AA derivatives as radical scavengers.
Spectroscopic studies on the antioxidant activity of p-coumaric acid.
Kiliç, Ismail; Yeşiloğlu, Yeşim
2013-11-01
p-coumaric acid (4-hydroxycinnamic acid), a phenolic acid, is a hydroxyl derivative of cinnamic acid. It decreases low density lipoprotein (LDL) peroxidation and reduces the risk of stomach cancer. In vitro radical scavenging and antioxidant capacity of p-coumaric acid were clarified using different analytical methodologies such as total antioxidant activity determination by ferric thiocyanate, hydrogen peroxide scavenging, 1,1-diphenyl-2-picryl-hydrazyl free radical (DPPH) scavenging, 2,2'-azino-bis(3-ethylbenzthiazoline-6-sulphonic acid) (ABTS) radical scavenging activity and superoxide anion radical scavenging, ferrous ions (Fe(2+)) chelating activity and ferric ions (Fe(3+)) reducing ability. p-Coumaric acid inhibited 71.2% lipid peroxidation of a linoleic acid emulsion at 45μg/mL concentration. On the other hand, butylated hydroxyanisole (BHA), butylated hydroxytoluene (BHT), α-tocopherol and ascorbic acid displayed 66.8%, 69.8%, 64.5% and 59.7% inhibition on the peroxidation of linoleic acid emulsion at the same concentration, respectively. In addition, p-coumaric acid had an effective DPPH scavenging, ABTS(+) scavenging, superoxide anion radical scavenging, hydrogen peroxide scavenging, ferric ions (Fe(3+)) reducing power and ferrous ions (Fe(2+)) chelating activities. Also, those various antioxidant activities were compared to BHA, BHT, α-tocopherol and ascorbic acid as references antioxidant compounds. These results suggested that p-coumaric acid can be used in the pharmacological and food industry because of these properties. Copyright © 2013 Elsevier B.V. All rights reserved.
Extraction and the Fatty Acid Profile of Rosa acicularis Seed Oil.
Du, Huanan; Zhang, Xu; Zhang, Ruchun; Zhang, Lu; Yu, Dianyu; Jiang, Lianzhou
2017-12-01
Rosa acicularis seed oil was extracted from Rosa acicularis seeds by the ultrasonic-assisted aqueous enzymatic method using cellulase and protease. Based on a single experiment, Plackett-Burman design was applied to ultrasonic-assisted aqueous enzymatic extraction of wild rose seed oil. The effects of enzyme amount, hydrolysis temperature and initial pH on total extraction rate of wild rose seed oil was studied by using Box-Behnken optimize methodology. Chemical characteristics of a sample of Rosa acicularis seeds and Rosa acicularis seed oil were characterized in this work. The tocopherol content was 200.6±0.3 mg/100 g oil. The Rosa acicularis seed oil was rich in linoleic acid (56.5%) and oleic acid (34.2%). The saturated fatty acids included palmitic acid (4%) and stearic acid (2.9%). The major fatty acids in the sn-2 position of triacylglycerol in Rosa acicularis oil were linoleic acid (60.6%), oleic acid (33.6%) and linolenic acid (3.2%). According to the 1,3-random-2-random hypothesis, the dominant triacylglycerols were LLL (18%), LLnL (1%), LLP (2%), LOL (10%), LLSt (1.2%), PLP (0.2%), LLnP (0.1%), LLnO (0.6%) and LOP (1.1%). This work could be useful for developing applications for Rosa acicularis seed oil.
Vogna, Davide; Marotta, Raffaele; Napolitano, Alessandra; D'Ischia, Marco
2002-08-23
The advanced oxidation chemistry of the antipyretic drug paracetamol (1) with the UV/H(2)O(2) system was investigated by an integrated methodology based on (15)N-labeling and GC-MS, HPLC, and 2D (1)H, (13)C, and (15)N NMR analysis. Main degradation pathways derived from three hydroxylation steps, leading to 1,4-hydroquinone/1,4-benzoquinone, 4-acetylaminocatechol and, to a much lesser extent, 4-acetylaminoresorcine. Oxidation of the primary aromatic intermediates, viz. 4-acetylaminocatechol, 1,4-hydroquinone, 1,4-benzoquinone, and 1,2,4-benzenetriol, resulted in a series of nitrogenous and non-nitrogenous degradation products. The former included N-acetylglyoxylamide, acetylaminomalonic acid, acetylaminohydroxymalonic acid, acetylaminomaleic acid, diastereoisomeric 2-acetylamino-3-hydroxybutanedioic acids, 2-acetylaminobutenedioic acid, 3-acetylamino-4-hydroxy-2-pentenedioic acid, and 2,4-dihydroxy-3-acetylamino-2-pentenedioic acid, as well as two muconic and hydroxymuconic acid derivatives. (15)N NMR spectra revealed the accumulation since the early stages of substantial amounts of acetamide and oxalic acid monoamide. These results provide the first insight into the advanced oxidation chemistry of a 4-aminophenol derivative by the UV/H(2)O(2) system, and highlight the investigative potential of integrated GC-MS/NMR methodologies based on (15)N-labeling to track degradation pathways of nitrogenous species.
Pham, Anh-Tung; Lee, Jeong-Dong; Shannon, J Grover; Bilyeu, Kristin D
2011-09-01
The alteration of fatty acid profiles in soybean to improve soybean oil quality has been a long-time goal of soybean researchers. Soybean oil with elevated oleic acid is desirable because this monounsaturated fatty acid improves the nutrition and oxidative stability of soybean oil compared to other oils. In the lipid biosynthetic pathway, the enzyme fatty acid desaturase 2 (FAD2) is responsible for the conversion of oleic acid precursors to linoleic acid precursors in developing soybean seeds. Two genes encoding FAD2-1A and FAD2-1B were identified to be expressed specifically in seeds during embryogenesis and have been considered to hold an important role in controlling the seed oleic acid content. A total of 22 soybean plant introduction (PI) lines identified to have an elevated oleic acid content were characterized for sequence mutations in the FAD 2-1A and FAD2-1B genes. PI 603452 was found to contain a deletion of a nucleotide in the second exon of FAD2-1A. These important SNPs were used in developing molecular marker genotyping assays. The assays appear to be a reliable and accurate tool to identify the FAD 2-1A and FAD2-1B genotype of wild-type and mutant plants. PI 603452 was subsequently crossed with PI 283327, a soybean line that has a mutation in FAD2-1B. Interestingly, soybean lines carrying both homozygous insertion/deletion mutation (indel) FAD2-1A alleles and mutant FAD2-1B alleles have an average of 82-86% oleic acid content, compared to 20% in conventional soybean, and low levels of linoleic and linolenic acids. The newly identified indel mutation in the FAD2-1A gene offers a simple method for the development of high oleic acid commercial soybean varieties.
NASA Technical Reports Server (NTRS)
Nonhebel, H. M.; Bandurski, R. S.
1984-01-01
Radiolabeled oxindole-3-acetic acid was metabolized by roots, shoots, and caryopses of dark grown Zea mays seedlings to 2,3-dihydro-7-hydroxy-2-oxo-1H indole-3-acetic acid-7'-O-beta-D-glycopyranoside with the simpler name of 7-hydroxyoxindole-3-acetic acid-glucoside. This compound was also formed from labeled indole-3-acetic acid supplied to intact seedlings and root segments. The glucoside of 7-hydroxyoxindole-3-acetic acid was also isolated as an endogenous compound in the caryopses and shoots of 4-day-old seedlings. It accumulates to a level of 4.8 nanomoles per plant in the kernel, more than 10 times the amount of oxindole-3-acetic acid. In the shoot it is present at levels comparable to that of oxindole-3-acetic acid and indole-3-acetic acid (62 picomoles per shoot). We conclude that 7-hydroxyoxindole-3-acetic acid-glucoside is a natural metabolite of indole-3-acetic acid in Z. mays seedlings. From the data presented in this paper and in previous work, we propose the following route as the principal catabolic pathway for indole-3-acetic acid in Zea seedlings: Indole-3-acetic acid --> Oxindole-3-acetic acid --> 7-Hydroxyoxindole-3-acetic acid --> 7-Hydroxyoxindole-3-acetic acid-glucoside.
Ferruz, Elena; Atanasova-Pénichon, Vessela; Bonnin-Verdal, Marie-Noëlle; Marchegay, Gisèle; Pinson-Gadais, Laëtitia; Ducos, Christine; Lorán, Susana; Ariño, Agustín; Barreau, Christian; Richard-Forget, Florence
2016-04-04
The effect of natural phenolic acids was tested on the growth and production of T-2 and HT-2 toxins by Fusarium langsethiae and F. sporotrichioides, on Mycotoxin Synthetic medium. Plates treated with 0.5 mM of each phenolic acid (caffeic, chlorogenic, ferulic and p-coumaric) and controls without phenolic acid were incubated for 14 days at 25 °C. Fungal biomass of F. langsethiae and F. sporotrichioides was not reduced by the phenolic acids. However, biosynthesis of T-2 toxin by F. langsethiae was significantly reduced by chlorogenic (23.1%) and ferulic (26.5%) acids. Production of T-2 by F. sporotrichioides also decreased with ferulic acid by 23% (p < 0.05). In contrast, p-coumaric acid significantly stimulated the production of T-2 and HT-2 toxins for both strains. A kinetic study of F. langsethiae with 1 mM ferulic acid showed a significant decrease in fungal biomass, whereas T-2 production increased after 10 days of incubation. The study of gene expression in ferulic supplemented cultures of F. langsethiae revealed a significant inhibition for Tri5, Tri6 and Tri12 genes, while for Tri16 the decrease in gene expression was not statistically significant. Overall, results indicated that phenolic acids had a variable effect on fungal growth and mycotoxin production, depending on the strain and the concentration and type of phenolic acid assayed.
Enhanced Synthesis of Alkyl Amino Acids in Miller's 1958 H2S Experiment
NASA Technical Reports Server (NTRS)
Parker, Eric T.; Cleaves, H. James; Callahan, Michael P.; Dworkin, James P.; Glavin, Daniel P.; Lazcano, Antonio; Bada, Jeffrey L.
2011-01-01
Stanley Miller's 1958 H2S-containing experiment, which included a simulated prebiotic atmosphere of methane (CH4), ammonia (NH3), carbon dioxide (CO2), and hydrogen sulfide (H2S) produced several alkyl amino acids, including the alpha-, beta-, and gamma-isomers of aminobutyric acid (ABA) in greater relative yields than had previously been reported from his spark discharge experiments. In the presence of H2S, aspariic and glutamic acids could yield alkyl amino acids via the formation of thioimide intermediates. Radical chemistry initiated by passing H2S through a spark discharge could have also enhanced alkyl amino acid synthesis by generating alkyl radicals that can help form the aldehyde and ketone precursors to these amino acids. We propose mechanisms that may have influenced the synthesis of certain amino acids in localized environments rich in H2S and lightning discharges, similar to conditions near volcanic systems on the early Earth, thus contributing to the prebiotic chemical inventory of the primordial Earth.
40 CFR 180.331 - 4-(2,4-Dichlorophenoxy) butyric acid; tolerances for residues.
Code of Federal Regulations, 2010 CFR
2010-07-01
... 40 Protection of Environment 23 2010-07-01 2010-07-01 false 4-(2,4-Dichlorophenoxy) butyric acid... Tolerances § 180.331 4-(2,4-Dichlorophenoxy) butyric acid; tolerances for residues. (a) General. Tolerances are established for residues of the herbicide 4-(2,4-dichlorophenoxy) butyric acid (2,4-DB), both free...
40 CFR 180.331 - 4-(2,4-Dichlorophenoxy) butyric acid; tolerances for residues.
Code of Federal Regulations, 2013 CFR
2013-07-01
... 40 Protection of Environment 25 2013-07-01 2013-07-01 false 4-(2,4-Dichlorophenoxy) butyric acid... Tolerances § 180.331 4-(2,4-Dichlorophenoxy) butyric acid; tolerances for residues. (a) General. Tolerances are established for residues of the herbicide 4-(2,4-dichlorophenoxy) butyric acid (2,4-DB), both free...
40 CFR 180.331 - 4-(2,4-Dichlorophenoxy) butyric acid; tolerances for residues.
Code of Federal Regulations, 2011 CFR
2011-07-01
... 40 Protection of Environment 24 2011-07-01 2011-07-01 false 4-(2,4-Dichlorophenoxy) butyric acid... Tolerances § 180.331 4-(2,4-Dichlorophenoxy) butyric acid; tolerances for residues. (a) General. Tolerances are established for residues of the herbicide 4-(2,4-dichlorophenoxy) butyric acid (2,4-DB), both free...
40 CFR 180.331 - 4-(2,4-Dichlorophenoxy) butyric acid; tolerances for residues.
Code of Federal Regulations, 2014 CFR
2014-07-01
... 40 Protection of Environment 24 2014-07-01 2014-07-01 false 4-(2,4-Dichlorophenoxy) butyric acid... Tolerances § 180.331 4-(2,4-Dichlorophenoxy) butyric acid; tolerances for residues. (a) General. Tolerances are established for residues of the herbicide 4-(2,4-dichlorophenoxy) butyric acid (2,4-DB), both free...
40 CFR 180.331 - 4-(2,4-Dichlorophenoxy) butyric acid; tolerances for residues.
Code of Federal Regulations, 2012 CFR
2012-07-01
... 40 Protection of Environment 25 2012-07-01 2012-07-01 false 4-(2,4-Dichlorophenoxy) butyric acid... Tolerances § 180.331 4-(2,4-Dichlorophenoxy) butyric acid; tolerances for residues. (a) General. Tolerances are established for residues of the herbicide 4-(2,4-dichlorophenoxy) butyric acid (2,4-DB), both free...
Cho, Hui Hun; Kim, Si Hyun; Heo, Jun Hyuk; Moon, Young Eel; Choi, Young Hun; Lim, Dong Cheol; Han, Kwon-Hoon; Lee, Jung Heon
2016-06-21
We report the development of a colorimetric sensor that allows for the quantitative measurement of the acid content via acid-base titration in a single-step. In order to create the sensor, we used a cobalt coordination system (Co-complex sensor) that changes from greenish blue colored Co(H2O)4(OH)2 to pink colored Co(H2O)6(2+) after neutralization. Greenish blue and pink are two complementary colors with a strong contrast. As a certain amount of acid is introduced to the Co-complex sensor, a portion of greenish blue colored Co(H2O)4(OH)2 changes to pink colored Co(H2O)6(2+), producing a different color. As the ratio of greenish blue and pink in the Co-complex sensor is determined by the amount of neutralization reaction occurring between Co(H2O)4(OH)2 and an acid, the sensor produced a spectrum of green, yellow green, brown, orange, and pink colors depending on the acid content. In contrast, the color change appeared only beyond the end point for normal acid-base titration. When we mixed this Co-complex sensor with different concentrations of citric acid, tartaric acid, and malic acid, three representative organic acids in fruits, we observed distinct color changes for each sample. This color change could also be observed in real fruit juice. When we treated the Co-complex sensor with real tangerine juice, it generated diverse colors depending on the concentration of citric acid in each sample. These results provide a new angle on simple but quantitative measurements of analytes for on-site usage in various applications, such as in food, farms, and the drug industry.
Rup, Sandrine; Zimmermann, François; Meux, Eric; Schneider, Michel; Sindt, Michele; Oget, Nicolas
2009-02-01
Carboxylic acids and diacids were synthesized from monoenic fatty acids by using RuO4 catalysis, under ultrasonic irradiation, in various mixtures of solvents. Ultrasound associated with Aliquat 336 have promoted in water, the quantitative oxidative cleavage of the CH=CH bond of oleic acid. A design of experiment (DOE) shows that the optimal mixture of solvents (H2O/MeCN, ratio 1/1, 2.2% RuCl3/4.1 eq. NaIO4) gives 81% azelaic acid and 97% pelargonic acid. With the binary heterogeneous mixture H2O/AcOEt, the oxidation of the oleic acid leads to a third product, the alpha-dione 9,10-dioxostearic acid.
Jeong, Tae Su; Choi, Chang Ho; Lee, Ji Ye; Oh, Kyeong Keun
2012-07-01
Acid-catalyzed hydrothermal hydrolysis is one path to cellulosic glucose and subsequently to its dehydration end products such as hydroxymethyl furfural (HMF), formic acid and levulinic acid. The effect of sugar decomposition not only lowers the yield of fermentable sugars but also forms decomposition products that inhibit subsequent fermentation. The present experiments were conducted with four different acid catalysts (H(2)SO(4), HNO(3), HCl, and H(3)PO(4)) at various acid normalities (0.5-2.1N) in batch reactors at 180-210 °C. From the results, H(2)SO(4) was the most suitable catalyst for glucose production, but glucose decomposition occurred during the hydrolysis. The glucose production was maximized at 160.7 °C, 2.0% (w/v) H(2)SO(4), and 40 min, but resulted in a low glucan yield of 33.05% due to the decomposition reactions, which generated formic acid and levulinic acid. The highest concentration of levulinic acid, 7.82 g/L, was obtained at 181.2 °C, 2.0% (w/v) H(2)SO(4), and 40 min. Copyright © 2012 Elsevier Ltd. All rights reserved.
Toyota, S; Hirosawa, S; Aoki, N
1994-02-01
Alpha 2-plasmin inhibitor (alpha 2PI) deficiency Okinawa results from defective secretion of the inhibitor from the liver and appears to be a direct consequence of the deletion of Glu137 in the amino acid sequence of alpha 2PI. To examine the effects of replacing the amino acid occupying position 137 or deleting its neighboring amino acid on alpha 2PI secretion, we used oligonucleotide-directed mutagenesis of alpha 2PI cDNA to change the codon specifying Glu137 or delete a codon specifying its neighboring amino acid. The effects were determined by pulse-chase experiments and by enzyme-linked immunosorbent assay of media from transiently transfected COS-7 cells. Replacement of Glu137 with an amino acid other than Cys had little effect on alpha 2PI secretion. In contrast, deletion of an amino acid in a region spanning a sequence of less than 30 amino acids including positions 127 and 137 severely impaired the secretion. The results suggest that structural integrity of the region, rather than its component amino acids, is important for the intracellular transport and secretion of alpha 2PI.
Jones, J A; Blecher, M
1966-05-01
The chemical synthesis and characterization of three intermediates in the Beta oxidation of palmitic acid-1-(14)C by rat liver mitochondria, namely, 3-ketohexadecanoic acid-1-(14)C, DL-3-hydroxyhexadecanoic acid-1-(14)C, and trans-2-hexadecenoic acid-1-(14)C, are described.
Sonolytic degradation of butyric acid in aqueous solutions.
Dükkancı, Meral; Gündüz, Gönül
2013-11-15
The sonolytic degradation of butyric acid was investigated in an ultrasonic reactor emitting waves at 850 kHz. The effects of the ultrasonic power, the initial concentration of butyric acid, and the addition of H2O2 were studied on the degradation of butyric acid. In the sonication of butyric acid, degradation degrees as high as 31.5% could be achieved at a power of 31 W, at an initial concentration of 2.8 mM butyric acid with the addition of 0.34 M H2O2 for a sonication time of 5 h. The degradation of butyric acid increased with irradiation time, indicating first order kinetics. Copyright © 2013 Elsevier Ltd. All rights reserved.
40 CFR 180.473 - Glufosinate ammonium; tolerances for residues.
Code of Federal Regulations, 2010 CFR
2010-07-01
... residues of the herbicide glufosinate-ammonium (butanoic acid, 2-amino-4-(hydroxymethylphosphinyl...-propionic acid, expressed as 2-amino-4-(hydroxymethylphosphinyl)butanoic acid equivalents, in or on the... herbicide glufosinate ammonium, butanoic acid, 2-amino-4-(hydroxymethylphosphinyl)-, monoammonium salt and...
Melton, Elaina M.; Cerny, Ronald L.; DiRusso, Concetta C.; Black, Paul N.
2014-01-01
In mammals, the fatty acid transport proteins (FATP1 through FATP6) are members of a highly conserved family of proteins, which function in fatty acid transport proceeding through vectorial acylation and in the activation of very long chain fatty acids, branched chain fatty acids and secondary bile acids. FATP1, 2 and 4, for example directly function in fatty acid transport and very long chain fatty acids activation while FATP5 does not function in fatty acid transport but activates secondary bile acids. In the present work, we have used stable isotopically labeled fatty acids differing in carbon length and saturation in cells expressing FATP2 to gain further insights into how this protein functions in fatty acid transport and intracellular fatty acid trafficking. Our previous studies showed the expression of FATP2 modestly increased C16:0-CoA and C20:4-CoA and significantly increased C18:3-CoA and C22:6-CoA after 4hr. The increases in C16:0-CoA and C18:3-CoA suggest FATP2 must necessarily partner with a long chain acyl CoA synthetase (Acsl) to generate C16:0-CoA and C18:3-CoA through vectorial acylation. The very long chain acyl CoA synthetase activity of FATP2 is consistent in the generation of C20:4-CoA and C22:6-CoA coincident with transport from their respective exogenous fatty acids. The trafficking of exogenous fatty acids into phosphatidic acid (PA) and into the major classes of phospholipids (phosphatidylcholine (PC), phosphatidylethanolamine (PE), phosphatidylinositol (PI), and phosphatidyserine (PS)) resulted in distinctive profiles, which changed with the expression of FATP2. The trafficking of exogenous C16:0 and C22:6 into PA was significant where there was 6.9- and 5.3-fold increased incorporation, respectively, over the control; C18:3 and C20:4 also trended to increase in the PA pool while there were no changes for C18:1 and C18:2. The trafficking of C18:3 into PC and PI trended higher and approached significance. In the case of C20:4, expression of FATP2 resulted in increases in all four classes of phospholipid, indicating little selectivity. In the case of C22:6, there were significant increases of this exogenous fatty acids being trafficking into PC and PI. Collectively, these data support the conclusion that FATP2 has a dual function in the pathways linking the transport and activation of exogenous fatty acids. We discuss the differential roles of FATP2 and its role in both fatty acid transport and fatty acid activation in the context of lipid homeostasis. PMID:24113382
Melton, Elaina M; Cerny, Ronald L; DiRusso, Concetta C; Black, Paul N
2013-11-01
In mammals, the fatty acid transport proteins (FATP1 through FATP6) are members of a highly conserved family of proteins, which function in fatty acid transport proceeding through vectorial acylation and in the activation of very long chain fatty acids, branched chain fatty acids and secondary bile acids. FATP1, 2 and 4, for example directly function in fatty acid transport and very long chain fatty acids activation while FATP5 does not function in fatty acid transport but activates secondary bile acids. In the present work, we have used stable isotopically labeled fatty acids differing in carbon length and saturation in cells expressing FATP2 to gain further insights into how this protein functions in fatty acid transport and intracellular fatty acid trafficking. Our previous studies showed the expression of FATP2 modestly increased C16:0-CoA and C20:4-CoA and significantly increased C18:3-CoA and C22:6-CoA after 4h. The increases in C16:0-CoA and C18:3-CoA suggest FATP2 must necessarily partner with a long chain acyl CoA synthetase (Acsl) to generate C16:0-CoA and C18:3-CoA through vectorial acylation. The very long chain acyl CoA synthetase activity of FATP2 is consistent in the generation of C20:4-CoA and C22:6-CoA coincident with transport from their respective exogenous fatty acids. The trafficking of exogenous fatty acids into phosphatidic acid (PA) and into the major classes of phospholipids (phosphatidylcholine (PC), phosphatidylethanolamine (PE), phosphatidylinositol (PI), and phosphatidyserine (PS)) resulted in distinctive profiles, which changed with the expression of FATP2. The trafficking of exogenous C16:0 and C22:6 into PA was significant where there was 6.9- and 5.3-fold increased incorporation, respectively, over the control; C18:3 and C20:4 also trended to increase in the PA pool while there were no changes for C18:1 and C18:2. The trafficking of C18:3 into PC and PI trended higher and approached significance. In the case of C20:4, expression of FATP2 resulted in increases in all four classes of phospholipid, indicating little selectivity. In the case of C22:6, there were significant increases of this exogenous fatty acids being trafficking into PC and PI. Collectively, these data support the conclusion that FATP2 has a dual function in the pathways linking the transport and activation of exogenous fatty acids. We discuss the differential roles of FATP2 and its role in both fatty acid transport and fatty acid activation in the context of lipid homeostasis. Copyright © 2013 Elsevier Inc. All rights reserved.
Code of Federal Regulations, 2013 CFR
2013-07-01
...-bis(2-hydroxyethyl)-, diester with C12-18 fatty acids, ethyl sulfates (salts). 721.3152 Section 721... Ethanaminium, N-ethyl-2-hydroxy-N,N-bis(2-hydroxyethyl)-, diester with C12-18 fatty acids, ethyl sulfates... ethanaminium, N-ethyl-2-hydroxy-N,N-bis(2-hydroxyethyl)-, diester with C12-18 fatty acids, ethyl sulfates...
Code of Federal Regulations, 2014 CFR
2014-07-01
...-bis(2-hydroxyethyl)-, diester with C12-18 fatty acids, ethyl sulfates (salts). 721.3152 Section 721... Ethanaminium, N-ethyl-2-hydroxy-N,N-bis(2-hydroxyethyl)-, diester with C12-18 fatty acids, ethyl sulfates... ethanaminium, N-ethyl-2-hydroxy-N,N-bis(2-hydroxyethyl)-, diester with C12-18 fatty acids, ethyl sulfates...
Code of Federal Regulations, 2012 CFR
2012-07-01
...-bis(2-hydroxyethyl)-, diester with C12-18 fatty acids, ethyl sulfates (salts). 721.3152 Section 721... Ethanaminium, N-ethyl-2-hydroxy-N,N-bis(2-hydroxyethyl)-, diester with C12-18 fatty acids, ethyl sulfates... ethanaminium, N-ethyl-2-hydroxy-N,N-bis(2-hydroxyethyl)-, diester with C12-18 fatty acids, ethyl sulfates...
Code of Federal Regulations, 2011 CFR
2011-07-01
...-bis(2-hydroxyethyl)-, diester with C12-18 fatty acids, ethyl sulfates (salts). 721.3152 Section 721... Ethanaminium, N-ethyl-2-hydroxy-N,N-bis(2-hydroxyethyl)-, diester with C12-18 fatty acids, ethyl sulfates... ethanaminium, N-ethyl-2-hydroxy-N,N-bis(2-hydroxyethyl)-, diester with C12-18 fatty acids, ethyl sulfates...
Anderson, J. W.; Fowden, L.
1970-01-01
1. Phenylalanyl-tRNA synthetases have been partially purified from cotyledons of seeds of Aesculus californica, which contains 2-amino-4-methylhex-4-enoic acid, and from four other species of Aesculus that do not contain this amino acid. The A. californica preparation was free from other aminoacyl-tRNA synthetases, and the contaminating synthetase activity in preparations from A. hippocastanum was decreased to acceptable limits by conducting assays of pyrophosphate exchange activity in 0.5m-potassium chloride. 2. The phenylalanyl-tRNA synthetase from each species activated 2-amino-4-methylhex-4-enoic acid with Km 30–40 times that for phenylalanine. The maximum velocity for 2-amino-4-methylhex-4-enoic acid was only 30% of that for phenylalanine with the A. californica enzyme, but the maximum velocities for the two substrates were identical for the other four species. 3. 2-Amino-4-methylhex-4-enoic acid was not found in the protein of A. californica, so discrimination against this amino acid probably occurs in the step of transfer to tRNA, though subcellular localization, or subsequent steps of protein synthesis could be involved. 4. Crotylglycine, methallylglycine, ethallylglycine, 2-aminohex-4,5-dienoic acid, 2-amino-5-methylhex-4-enoic acid, 2-amino-4-methylhex-4-enoic acid, β-(thien-2-yl)alanine, β-(pyrazol-1-yl)alanine, phenylserine and m-fluorophenylalanine were substrates for pyrophosphate exchange catalysed by the phenylalanyl-tRNA synthetases of A. californica or A. hippocastanum. Allylglycine, phenylglycine and 2-amino-4-phenylbutyric acid were inactive. PMID:5493504
Wang, Jiabin; Wu, Fangling; Zhao, Qi
2015-08-01
A C18 monolithic capillary column was utilized as the solid phase microextraction column to construct an in-tube SPME-HPLC system which was used to simultaneously extract and detect five phenoxy acid herbicides, including 2,4-dichlorophenoxyacetic acid (2,4-D), 2- (2-chloro)-phenoxy propionic acid (2,2-CPPA), 2-(3-chloro)-phenoxy propionic acid (2,3- CPPA), phenoxy propionic acid (PPA) and 2-(2,4-dichlorophenoxy) propionic acid (2,4-DP). The operating parameters of the in-tube SPME-HPLC system, including the length of the monolithic column, the sampling flow rate, the sampling time, the elution flow rate and the elution time, had been investigated in detail. The optimized operating parameters of the in-tube SPME-HPLC system were as follow: the length of the monolithic column was 20 cm, the sampling flow rate was 0. 04 mL/min, sampling time was 13 min; the elution flow rate was 0.02 mL/min, elution time was 5 min. Under the optimized conditions, the detection limits of the five phenoxy acid herbicides were as follows: 9 µg/L for PPA, 4 µg/L for 2,2-CPPA, 4 µg/L for 2,3-CPPA, 5 µg/L for 2,4-D, 5 µg/L for 2,4-DP. Compared with the HPLC method with direct injection, the combined system showed a good enrichment factors to the analytes. The recoveries of the five phenoxy acid herbicides were between 79.0% and 98.0% (RSD ≤ 3.9%). This method was successfully used to detect the five phenoxy acid herbicides in water samples with satisfactory results.
Effects of phosphoric acid on the lead-acid battery reactions
NASA Astrophysics Data System (ADS)
Ikeda, Osamu; Iwakura, Chiaki; Yoneyama, Hiroshi; Tamura, Hideo
1986-10-01
The addition of a small amount of phosphoric acid to 5 M H2SO4 (commercial electrolyte of lead-acid batteries) results in various positive effects on the lead-acid battery reactions: (1) depression of the corrosion rate of the lead substrate through a preferential formation of alpha-PbO2 on the substrate surface; (2) retardation of hard sulfate formation or of deactivation of active materials; and (3) change in the crystal morphology of PbSO2 formed on the discharge of PbO2. Most of these effects results from chemisorption of phosphoric acid on PbSO4 crystals produced in the discharge process of PbO2.
2010-01-01
Background The alteration of fatty acid profiles in soybean [Glycine max (L.) Merr.] to improve soybean oil quality is an important and evolving theme in soybean research to meet nutritional needs and industrial criteria in the modern market. Soybean oil with elevated oleic acid is desirable because this monounsaturated fatty acid improves the nutrition and oxidative stability of the oil. Commodity soybean oil typically contains 20% oleic acid and the target for high oleic acid soybean oil is approximately 80% of the oil; previous conventional plant breeding research to raise the oleic acid level to just 50-60% of the oil was hindered by the genetic complexity and environmental instability of the trait. The objective of this work was to create the high oleic acid trait in soybeans by identifying and combining mutations in two delta-twelve fatty acid desaturase genes, FAD2-1A and FAD2-1B. Results Three polymorphisms found in the FAD2-1B alleles of two soybean lines resulted in missense mutations. For each of the two soybean lines, there was one unique amino acid change within a highly conserved region of the protein. The mutant FAD2-1B alleles were associated with an increase in oleic acid levels, although the FAD2-1B mutant alleles alone were not capable of producing a high oleic acid phenotype. When existing FAD2-1A mutations were combined with the novel mutant FAD2-1B alleles, a high oleic acid phenotype was recovered only for those lines which were homozygous for both of the mutant alleles. Conclusions We were able to produce conventional soybean lines with 80% oleic acid in the oil in two different ways, each requiring the contribution of only two genes. The high oleic acid soybean germplasm developed contained a desirable fatty acid profile, and it was stable in two production environments. The presumed causative sequence polymorphisms in the FAD2-1B alleles were developed into highly efficient molecular markers for tracking the mutant alleles. The resources described here for the creation of high oleic acid soybeans provide a framework to efficiently develop soybean varieties to meet changing market demands. PMID:20828382
Pham, Anh-Tung; Lee, Jeong-Dong; Shannon, J Grover; Bilyeu, Kristin D
2010-09-09
The alteration of fatty acid profiles in soybean [Glycine max (L.) Merr.] to improve soybean oil quality is an important and evolving theme in soybean research to meet nutritional needs and industrial criteria in the modern market. Soybean oil with elevated oleic acid is desirable because this monounsaturated fatty acid improves the nutrition and oxidative stability of the oil. Commodity soybean oil typically contains 20% oleic acid and the target for high oleic acid soybean oil is approximately 80% of the oil; previous conventional plant breeding research to raise the oleic acid level to just 50-60% of the oil was hindered by the genetic complexity and environmental instability of the trait. The objective of this work was to create the high oleic acid trait in soybeans by identifying and combining mutations in two delta-twelve fatty acid desaturase genes, FAD2-1A and FAD2-1B. Three polymorphisms found in the FAD2-1B alleles of two soybean lines resulted in missense mutations. For each of the two soybean lines, there was one unique amino acid change within a highly conserved region of the protein. The mutant FAD2-1B alleles were associated with an increase in oleic acid levels, although the FAD2-1B mutant alleles alone were not capable of producing a high oleic acid phenotype. When existing FAD2-1A mutations were combined with the novel mutant FAD2-1B alleles, a high oleic acid phenotype was recovered only for those lines which were homozygous for both of the mutant alleles. We were able to produce conventional soybean lines with 80% oleic acid in the oil in two different ways, each requiring the contribution of only two genes. The high oleic acid soybean germplasm developed contained a desirable fatty acid profile, and it was stable in two production environments. The presumed causative sequence polymorphisms in the FAD2-1B alleles were developed into highly efficient molecular markers for tracking the mutant alleles. The resources described here for the creation of high oleic acid soybeans provide a framework to efficiently develop soybean varieties to meet changing market demands.
Yoshida, Toshiaki
2017-10-01
Pyrethroids are widely being used as household insecticides or mothproof repellents. An analytical method is described for determination of urinary metabolites as biomarkers for monitoring exposure to the pyrethroids. In total, 11 urinary metabolites, 3-(2-carboxyprop-1-enyl)-2,2-dimethylcyclopropanecarboxylic acid, 3-(2-chloro-3,3,3-trifluoroprop-1-enyl)-2,2-dimethylcyclopropanecarboxylic acid, 3-(2,2-dichlorovinyl)-2,2-dimethylcyclopropanecarboxylic acid, 2,2-dimethyl-3-(2-methylprop-1-enyl)cyclopropanecarboxylic acid, 4-fluoro-3-phenoxybenzoic acid, 4-methoxymethyl-2,3,5,6-tetrafluorobenzly alcohol, 2-methyl-3-phenylbenzoic acid, 4-methyl-2,3,5,6-tetrafluorobenzyl alcohol, 3-phenoxybenzoic acid, 2,3,5,6-tetrafluorobenzoic acid and 2,2,3,3-tetramethylcyclopropanecarboxylic acid, were enzymatically hydrolyzed and extracted with toluene. After transformation to their tert-butyldimethylsilyl or trimethylsilyl derivatives, they were analyzed by gas chromatography/mass spectrometry in electron impact ionization mode. The calibration curves for the metabolite were linear over the concentration range of 0-30 μg/L in urine. They could be determined accurately and precisely (detection limits: 0.01-0.12 μg/L, quantification limits: 0.04-0.41 μg/L). The urine samples collected could be stored for up to 1 month at -20°C in a freezer. The proposed method was applied to determine urine samples from several health volunteers. The method was considered to be available for monitoring pyrethroid exposure in the general population. © The Author 2017. Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com.
Development of marker-free transgenic Jatropha plants with increased levels of seed oleic acid
2012-01-01
Background Jatropha curcas is recognized as a new energy crop due to the presence of the high amount of oil in its seeds that can be converted into biodiesel. The quality and performance of the biodiesel depends on the chemical composition of the fatty acids present in the oil. The fatty acids profile of the oil has a direct impact on ignition quality, heat of combustion and oxidative stability. An ideal biodiesel composition should have more monounsaturated fatty acids and less polyunsaturated acids. Jatropha seed oil contains 30% to 50% polyunsaturated fatty acids (mainly linoleic acid) which negatively impacts the oxidative stability and causes high rate of nitrogen oxides emission. Results The enzyme 1-acyl-2-oleoyl-sn-glycero-3-phosphocholine delta 12-desaturase (FAD2) is the key enzyme responsible for the production of linoleic acid in plants. We identified three putative delta 12 fatty acid desaturase genes in Jatropha (JcFAD2s) through genome-wide analysis and downregulated the expression of one of these genes, JcFAD2-1, in a seed-specific manner by RNA interference technology. The resulting JcFAD2-1 RNA interference transgenic plants showed a dramatic increase of oleic acid (> 78%) and a corresponding reduction in polyunsaturated fatty acids (< 3%) in its seed oil. The control Jatropha had around 37% oleic acid and 41% polyunsaturated fatty acids. This indicates that FAD2-1 is the major enzyme responsible for converting oleic acid to linoleic acid in Jatropha. Due to the changes in the fatty acids profile, the oil of the JcFAD2-1 RNA interference seed was estimated to yield a cetane number as high as 60.2, which is similar to the required cetane number for conventional premium diesel fuels (60) in Europe. The presence of high seed oleic acid did not have a negative impact on other Jatropha agronomic traits based on our preliminary data of the original plants under greenhouse conditions. Further, we developed a marker-free system to generate the transgenic Jatropha that will help reduce public concerns for environmental issues surrounding genetically modified plants. Conclusion In this study we produced seed-specific JcFAD2-1 RNA interference transgenic Jatropha without a selectable marker. We successfully increased the proportion of oleic acid versus linoleic in Jatropha through genetic engineering, enhancing the quality of its oil. PMID:22377043
Development of N(2) Sensor for Determination of PN(2) in Body Tissues.
1986-08-01
NK3)4C1 2 ]Cl Acid -140 -340 Acid -120 -280 +500 . + Zn Amalgam +700 +900 2 cis-Ru(N( 3 )4C1 2 C1 Buffer -130 -305 (major) ,450 + Zn Amalgam -210...increase under N 2 -400 mV under N 2 cis- [1u (en) 2C12 )C1 Buffer -125 -350 Buffer + Zn - so -400 .475 Amalgam +780 cis-(Ru(en)2Br 2 ] r Acid -120...375 Acid + Zn - 0 -280 plateau Amalgam 600-8SO cis- ([ (bipyr)C12 1Cl Buffer .455 +320 Buffer + Zn +575 +380 Nme Amalgam 1Acid = 0.1M H2SO42Buffer
Cooxidation of 13-cis-retinoic acid by prostaglandin H synthase.
Samokyszyn, V M; Sloane, B F; Honn, K V; Marnett, L J
1984-10-30
Cooxidative metabolism of 13-cis-retinoic acid (13-CIS) via prostaglandin H synthase was investigated employing ram seminal vesicle microsomes. Oxidation of 13-CIS utilizing H2O2, 13-hydroperoxy-9-cis-11-trans-octadecadienoic acid (13-OOH-18:2), or 1-hydroperoxy-5-phenyl-4-pentene was detected by measurement of O2 incorporation. UV spectroscopy and HPLC of extracted incubation mixtures demonstrated that 13-CIS was metabolized to oxidized derivatives. Similar spectral changes and HPLC profiles were obtained with H2O2, 13-OOH-18:2, or arachidonic acid as substrates. 4-Hydroxy-13-cis-retinoic acid and all trans-retinoic acid were products of cooxidation as well as other polar metabolites. Oxidation was inhibited by the antioxidant butylated hydroxyanisole and the spin trap, nitrosobenzene. These results indicate that 13-cis-retinoic acid is cooxidized by prostaglandin H synthase and suggest a free radical mechanism resembling that of lipid peroxidation.
[Ganoderma triterpenoids from aqueous extract of Ganoderma lucidum].
Che, Xian-Qiang; Li, Shao-Ping; Zhao, Jing
2017-05-01
A new triterpenoid and 18 analogues were isolated from the water extract of Ganoderma lucidum by column chromatographic techniques, including silica gel, ODS, Sephadex LH-20, and HPLC. The new compound was elucidated as 2β-acetoxy-3β,25-dihydroxy-7,11,15-trioxo-lanost-8-en-26-oic acid on the basis of analyses of extensive spectroscopic data and its physicochemical properties. Comparison of NMR data with those reported in literature, the known analogues were determined as ganoderic acid H (2), 12β-acetoxy-3β,7β-dihydroxy-11,15,23-trioxo-lanost-8,16-dien-26-oic acid (3), ganoderenic acid D (4),ganoderic acid C1 (5),ganoderic acid G (6),3β,7β-dihydroxy-11,15,23-trioxo-lanost-8,16-dien-26-oic acid (7),ganoderic acid B (8),ganoderic acid C6 (9),3β,15α-dihydroxy-7,11,23-trioxo-lanost-8,16-dien-26-oic acid (10),ganoderic acid A (11),ganolucidic acid A (12),lucidenic acid E2 (13),lucidenic acid N (14),lucidenic acid P (15), lucidenic acid B (16),lucidenic acid A (17),lucidenic acid C (18),and lucidenic acid L (19), respectively. Compound 1 is new compound and compounds 2-19 have been reported from G. lucidum. The present study enriches the knowledge of the chemical constituent of G. lucidum and completes chemical investigation of water decoction that is traditional use of G. lucidum. Copyright© by the Chinese Pharmaceutical Association.
NASA Astrophysics Data System (ADS)
Ozer, Demet; Köse, Dursun A.; Sahin, Onur; Oztas, Nursen A.
2018-04-01
Three boric acid mediated metal organic frameworks were synthesized by solution method with using succinic acid, fumaric acid and acetylene dicarboxylic acid as a ligand source and sodium as a metal source. The complexes were characterized by FT-IR, powder XRD, elemental analyses and single crystal measurements. The complexes with the formula, C4H18B2Na2O14, C4H16B2Na2O14 and C4H14B2Na2O14 were successfully obtained. BET surface area of complexes were calculated and found as 13.474 m2/g for catena-(tetrakis(μ2-hydroxo)-(μ2-trihydrogen borate)-(μ2-succinato)-di-sodium boric acid solvate), 1.692 m2/g for catena-(tetrakis(μ2-hydroxo)-(μ2-trihydrogen borate)-(μ2-fumarato)-di-sodium boric acid solvate) and 5.600 m2/g for catena-(tetrakis(μ2-hydroxo)-(μ2-trihydrogen borate)-(μ2-acetylenedicarboxylato)-di-sodium boric acid solvate). Hydrogen storage capacities of the complexes were also studied at 77 K 1 bar pressure and found as 0.108%, 0.033%, 0.021% by mass. When different ligands were used, the pore volume, pore width and surface area of the obtained complexes were changed. As a consequence, hydrogen storage capacities also changed.
Effects of acid deposition on terrestrial ecosystems and their rehabilitation strategies in China.
Feng, Zong-wei; Miao, Hong; Zhang, Fu-zhu; Huang, Yi-zong
2002-04-01
South China has become the third largest region associated with acid deposition following Europe and North America, the area subject to damage by acid deposition increased from 1.75 million km2 in 1985 to 2.8 million km2 in 1993. Acid deposition has caused serious damage to ecosystem. Combined pollution of acid rain and SO2 showed the obvious multiple effects on crops. Vegetable was more sensitive to acid deposition than foodstuff crops. Annual economic loss of crops due to acid deposition damage in eleven provinces of south China was 4.26 billion RMB Yuan. Acid deposition caused serious damage to forest. Annual economic loss of wood volume was about 1.8 billion RMB Yuan and forest ecological benefit loss 16.2 billion in eleven provinces of south China. Acid deposition in south China was typical "sulfuric acid type". According to the thoughts of sustainable development, some strategies were brought forward as follows: (1) enhancing environmental management, specifying acid-controlling region, controlling and abating the total emission amount of SO2; (2) selecting practical energy technologies of clean coal, for example, cleansing and selecting coal, sulfur-fixed-type industrial briqutting, abating sulfur from waste gas and so on; (3) developing other energy sources to replace coal, including water electricity, atomic energy and the new energy such as solar energy, wind energy and so on; (4) in acid deposition region of south China, selecting acid-resistant type of crop and tree to decrease agricultural losses, planting more green fertilizer crops, using organic fertilizers and liming, in order to improve buffer capacities of soil.
Lupu, Daniel S; Cheatham, Carol L; Corbin, Karen D; Niculescu, Mihai D
2015-11-01
Polyunsaturated fatty acid metabolism in toddlers is regulated by a complex network of interacting factors. The contribution of maternal genetic and epigenetic makeup to this milieu is not well understood. In a cohort of mothers and toddlers 16 months of age (n = 65 mother-child pairs), we investigated the association between maternal genetic and epigenetic fatty acid desaturase 2 (FADS2) profiles and toddlers' n-6 and n-3 fatty acid metabolism. FADS2 rs174575 variation and DNA methylation status were interrogated in mothers and toddlers, as well as food intake and plasma fatty acid concentrations in toddlers. A multivariate fit model indicated that maternal rs174575 genotype, combined with DNA methylation, can predict α-linolenic acid plasma concentration in all toddlers and arachidonic acid concentrations in boys. Arachidonic acid intake was predictive for its plasma concentration in girls, whereas intake of 3 major n-3 species (eicosapentaenoic, docosapentaenoic, and docosahexaenoic acids) were predictive for their plasma concentrations in boys. FADS2 genotype and DNA methylation in toddlers were not related to plasma concentrations or food intakes, except for CpG8 methylation. Maternal FADS2 methylation was a predictor for the boys' α-linolenic acid intakes. This exploratory study suggests that maternal FADS2 genetic and epigenetic status could be related to toddlers' polyunsaturated fatty acid metabolism. Copyright © 2015 Elsevier Inc. All rights reserved.
Further Studies on Oxalic Acid Biosynthesis in Oxalate-accumulating Plants 1
Nuss, Richard F.; Loewus, Frank A.
1978-01-01
l-Ascorbic acid functions as a precursor of oxalic acid in several oxalate-accumulating plants. The present study extends this observation to include Rumex crispus L. (curly dock), Amaranthus retroflexus L. (red root pigweed), Chenopodium album L. (lamb's-quarters), Beta vulgaris L. (sugar beet), Halogeton glomeratus M. Bieb. (halogeton), and Rheum rhabarbarum L. (rhubarb). Several species with low oxalate content are also examined. When l-[1-14C]ascorbic acid is supplied to young seedlings of R. crispus or H. glomeratus, a major portion of the 14C is released over a 24-hour period as 14CO2 and only a small portion is recovered as [14C]oxalate, unlike cuttings from 2- or 4-month-old plants which retain a large part of the 14C as [14C]oxalic acid and release very little 14CO2. Support for an intermediate role of oxalate in the release of 14CO2 from l-[1-14C]ascorbic acid is seen in the rapid release of 14CO2 by R. crispus and H. glomeratus seedlings labeled with [14C]oxalic acid. The common origin of oxalic acid carbon in the C1 and C2 fragment from l-ascorbic acid is demonstrated by comparison of 14C content of oxalic acid in several oxalate-accumulators after cuttings or seedlings are supplied equal amounts of l-[1-14C]- or l-[UL-14C]ascorbic acid. Theoretically, l-[1-14C]ascorbic acid will produce labeled oxalic acid containing three times as much 14C as l-[UL-14C]ascorbic acid when equal amounts of label are provided. Experimentally, a ratio of 2.7 ± 0.5 is obtained in duplicate experiments with six different species. PMID:16660342
40 CFR 180.325 - 2-(m-Chlorophenoxy) propionic acid; tolerances for residues.
Code of Federal Regulations, 2010 CFR
2010-07-01
... 40 Protection of Environment 23 2010-07-01 2010-07-01 false 2-(m-Chlorophenoxy) propionic acid... Tolerances § 180.325 2-(m-Chlorophenoxy) propionic acid; tolerances for residues. (a) General. A tolerance is established for negligible residues of the plant regulator 2-(m-chlorophenoxy) propionic acid from application...
40 CFR 721.1728 - Benzoic acid, 2-(3-phenylbutylidene)amino-, methyl ester.
Code of Federal Regulations, 2011 CFR
2011-07-01
... New Uses for Specific Chemical Substances § 721.1728 Benzoic acid, 2-(3-phenylbutylidene)amino... substance identified as benzoic acid, 2-(3-phenylbutylidene)amino-, methyl ester (PMN P-85-1211) is subject... 40 Protection of Environment 31 2011-07-01 2011-07-01 false Benzoic acid, 2-(3-phenylbutylidene...
40 CFR 721.1728 - Benzoic acid, 2-(3-phenylbutylidene)amino-, methyl ester.
Code of Federal Regulations, 2010 CFR
2010-07-01
... New Uses for Specific Chemical Substances § 721.1728 Benzoic acid, 2-(3-phenylbutylidene)amino... substance identified as benzoic acid, 2-(3-phenylbutylidene)amino-, methyl ester (PMN P-85-1211) is subject... 40 Protection of Environment 30 2010-07-01 2010-07-01 false Benzoic acid, 2-(3-phenylbutylidene...
21 CFR 862.1255 - 2,3-Diphosphoglyceric acid test system.
Code of Federal Regulations, 2013 CFR
2013-04-01
... acid test system is a device intended to measure 2,3-diphosphoglyceric acid (2,3-DPG) in erythrocytes (red blood cells). Measurements of 2,3-diphosphoglyceric acid are used in the diagnosis and treatment... the quality of stored blood. (b) Classification. Class I (general controls). The device is exempt from...
Martin, Gregory G.; Atshaves, Barbara P.; Landrock, Kerstin K.; Landrock, Danilo; Storey, Stephen M.; Howles, Philip N.; Kier, Ann B.
2014-01-01
On the basis of their abilities to bind bile acids and/or cholesterol, the physiological role(s) of liver fatty acid-binding protein (L-FABP) and sterol carrier protein (SCP) 2/SCP-x (SCP-2/SCP-x) gene products in biliary bile acid and cholesterol formation was examined in gene-ablated male mice. L-FABP (LKO) or L-FABP/SCP-2/SCP-x [triple-knockout (TKO)] ablation markedly decreased hepatic bile acid concentration, while SCP-2/SCP-x [double-knockout (DKO)] ablation alone had no effect. In contrast, LKO increased biliary bile acid, while DKO and TKO had no effect on biliary bile acid levels. LKO and DKO also altered biliary bile acid composition to increase bile acid hydrophobicity. Furthermore, LKO and TKO decreased hepatic uptake and biliary secretion of high-density lipoprotein (HDL)-derived 22-(N-(7-nitrobenz-2-oxa-1,3-diazol-4-yl)amino)-23,24-bisnor-5-cholen-3β-ol (NBD-cholesterol), while DKO alone had no effect. Finally, LKO and, to a lesser extent, DKO decreased most indexes contributing to cholesterol solubility in biliary bile. These results suggest different, but complementary, roles for L-FABP and SCP-2/SCP-x in biliary bile acid and cholesterol formation. L-FABP appears to function more in hepatic retention of bile acids as well as hepatic uptake and biliary secretion of HDL-cholesterol. Conversely, SCP-2/SCP-x may function more in formation and biliary secretion of bile acid, with less impact on hepatic uptake or biliary secretion of HDL-cholesterol. PMID:25277800
Effect of acetic acid on lipid accumulation by glucose-fed activated sludge cultures
DOE Office of Scientific and Technical Information (OSTI.GOV)
Mondala, Andro; Hernandez, Rafael; French, Todd
2012-01-01
The effect of acetic acid, a lignocellulose hydrolysis by-product, on lipid accumulation by activated sludge cultures grown on glucose was investigated. This was done to assess the possible application of lignocellulose as low-cost and renewable fermentation substrates for biofuel feedstock production. Results: Biomass yield was reduced by around 54% at a 2 g L -1 acetic acid dosage but was increased by around 18% at 10 g L -1 acetic acid dosage relative to the control run. The final gravimetric lipid contents at 2 and 10 g L -1 acetic acid levels were 12.5 + 0.7% and 8.8 + 3.2%more » w/w, respectively, which were lower than the control (17.8 + 2.8% w/w). However, biodiesel yields from activated sludge grown with acetic acid (5.6 + 0.6% w/w for 2 g L -1 acetic acid and 4.2 + 3.0% w/w for 10 g L -1 acetic acid) were higher than in raw activated sludge (1-2% w/w). The fatty acid profiles of the accumulated lipids were similar with conventional plant oil biodiesel feedstocks. Conclusions: Acetic acid enhanced biomass production by activated sludge at high levels but reduced lipid production. Further studies are needed to enhance acetic acid utilization by activated sludge microorganisms for lipid biosynthesis.« less
NASA Technical Reports Server (NTRS)
Gupta, A.; Loew, G. H.; Lawless, J.
1983-01-01
A semiempirical molecular orbital method is used to characterize the binding of amino acids to hexahydrated Cu(2+) and Ni(2+), a process presumed to occur when they are adsorbed in the interlamellar space of homoionic smectite clays. Five alpha-amino acids, beta-alanine, and gamma-aminobutyric acid were used to investigate the metal ion and amino acid specificity in binding. It was assumed that the alpha, beta, and gamma-amino acids would bind as bidentate anionic ligands, forming either 1:1 or 1:2 six-coordinated five, six, and seven-membered-ring chelate complexes, respectively. Energies of complex formation, optimized geometries, and electron and spin distribution were determined; and steric constraints of binding of the amino acids to the ion-exchanged cations in the interlamellar spacing of a clay were examined. Results indicate that hexahydrated Cu(2+) forms more stable complexes than hexahydrated Ni(2+) with all the amino acids studied. However, among these amino acids, complex formation does not favor the adsorption of the biological subset. Calculated energetics of complex formation and steric constraints are shown to predict that 1:1 rather than 1:2 metal-amino acid complexes are generally favored in the clay.
Code of Federal Regulations, 2013 CFR
2013-07-01
..., carrier Lactic acid Solvent Lactic acid, 2-ethylhexyl ester (CAS Reg. No. 6283-86-9) Solvent Lactic acid, 2-ethylhexyl ester, (2S)- (CAS Reg. No. 186817-80-1) Solvent Lactic acid, n-propyl ester, (S); (CAS... agent Thiosulfuric acid, disodium salt, pentahydrate. (CAS Reg. No. 10102-17-7) Do. d-Alpha tocopherol...
Code of Federal Regulations, 2012 CFR
2012-07-01
..., carrier Lactic acid Solvent Lactic acid, 2-ethylhexyl ester (CAS Reg. No. 6283-86-9) Solvent Lactic acid, 2-ethylhexyl ester, (2S)- (CAS Reg. No. 186817-80-1) Solvent Lactic acid, n-propyl ester, (S); (CAS... coating agent Petroleum wax, conforming to 21 CFR 172.886(d) Coating agent Phosphoric acid Buffer...
Utilization of aromatic compounds by the Penicillium strain Bi 7/2.
Hofrichter, M; Scheibner, K
1993-01-01
The Penicillium strain Bi 7/2 utilized phenol, catechol, resorcinol, hydroquinone, pyrogallol, hydroxyhydroquinone, phloroglucinol, m- and p-cresol, orcinol, 4-methylcatechol, 4-methoxyphenol, 4-aminophenol, benzyl alcohol, benzoic acid, 2-, 3- and 4-hydroxybenzoic acid, anthranilic acid, protocatechuic acid and gallic acid as sole sources of carbon and energy. The central metabolites catechol, protocatechuic acid and hydroxyquinone could be determined by HPLC with diode-array detection. Pathways for the degradation of aromatic substances were proposed.
Wu, Zhi-Guo; Wang, Fang; Ning, Li-Qun; Stedtfeld, Robert D; Yang, Zong-Zheng; Cao, Jing-Guo; Sheng, Hong-Jie; Jiang, Xin
2017-06-01
Several bacteria have been isolated to degrade 4-chloronitrobenzene. Degradation of 4-chloronitrobenzene by Cupriavidus sp. D4 produces 5-chloro-2-picolinic acid as a dead-end by-product, a potential pollutant. To date, no bacterium that degrades 5-chloro-2-picolinic acid has been reported. Strain f1, isolated from a soil polluted by 4-chloronitrobenzene, was able to co-metabolize 5-chloro-2-picolinic acid in the presence of ethanol or other appropriate carbon sources. The strain was identified as Achromobacter sp. based on its physiological, biochemical characteristics, and 16S rRNA gene sequence analysis. The organism completely degraded 50, 100 and 200 mg L -1 of 5-chloro-2-picolinic acid within 48, 60, and 72 h, respectively. During the degradation of 5-chloro-2-picolinic acid, Cl - was released. The initial metabolic product of 5-chloro-2-picolinic acid was identified as 6-hydroxy-5-chloro-2-picolinic acid by LC-MS and NMR. Using a mixed culture of Achromobacter sp. f1 and Cupriavidus sp. D4 for degradation of 4-chloronitrobenzen, 5-chloro-2-picolinic acid did not accumulate. Results infer that Achromobacter sp. f1 can be used for complete biodegradation of 4-chloronitrobenzene in remedial applications.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Sekiguchi, J.; Katayama, S.; Yamada, Y.
1987-07-01
Penicillic acid-negative mutants were obtained from a color mutant derived from Penicillium cyclopium NRRL 1888 through N-methyl-N'-nitro-N-nitrosoguanidine treatment. One mutant (SK2N6) accumulated 6-methyl-1,2,4-benzenetriol, which was not previously known to be a metabolite of P. cyclopium, in addition to orsellinic acid and orcinol. The radioactivity of (1-/sup 14/C)acetic acid was rapidly incorporated into 6-methyl-1,2,4-benzenetriol in a culture of P. cyclopium SK2N6. Moreover, the radioactivity of (/sup 14/C)6-methyl-1,2,4-benzenetriol was efficiently incorporated into penicillic acid in a culture of P. cyclopium NRRL 1888. These data indicate that 6-methyl-1,2,4-benzenetriol is a precursor for penicillic acid biosynthesis. The results on the addition of 1,4-dihydroxy-6-methoxy-2-methylbenzene, 6-methoxy-2-methylbenzoquinonemore » (1,4), and 1-O-methylorcinol to a culture of P. cyclopium SK2N6 indicated that only the former two compounds are converted to penicillic acid. Thus, a new portion of the penicillic acid biosynthetic pathway is proposed.« less
Molecular basis of P450 OleTJE: an investigation of substrate binding mechanism and major pathways
NASA Astrophysics Data System (ADS)
Du, Juan; Liu, Lin; Guo, Li Zhong; Yao, Xiao Jun; Yang, Jian Ming
2017-05-01
Cytochrome P450 OleTJE has attracted much attention for its ability to catalyze the decarboxylation of long chain fatty acids to generate alkenes, which are not only biofuel molecule, but also can be used broadly for making lubricants, polymers and detergents. In this study, the molecular basis of the binding mechanism of P450 OleTJE for arachidic acid, myristic acid, and caprylic acid was investigated by utilizing conventional molecular dynamics simulation and binding free energy calculations. Moreover, random acceleration molecular dynamics (RAMD) simulations were performed to uncover the most probable access/egress channels for different fatty acids. The predicted binding free energy shows an order of arachidic acid < myristic acid < caprylic acid. Key residues interacting with three substrates and residues specifically binding to one of them were identified. The RAMD results suggest the most likely channel for arachidic acid, myristic acid, and caprylic acid are 2e/2b, 2a and 2f/2a, respectively. It is suggested that the reaction is easier to carry out in myristic acid bound system than those in arachidic acid and caprylic acid bound system based on the distance of Hβ atom of substrate relative to P450 OleTJE Compound I states. This study provided novel insight to understand the substrate preference mechanism of P450 OleTJE and valuable information for rational enzyme design for short chain fatty acid decarboxylation.
Effects of Sodium Glucose Cotransporter-2 Inhibitors on Serum Uric Acid in Type 2 Diabetes Mellitus.
Ahmadieh, Hala; Azar, Sami
2017-09-01
Hyperuricemia has been linked to metabolic syndrome, cardiovascular disease, and chronic kidney disease. Hyperuricemia and type 2 diabetes mellitus were inter-related, type 2 diabetes mellitus was more at risk of having a higher serum uric acid level, and also individuals with higher serum uric acid had higher risk of developing type 2 diabetes in the future. Insulin resistance seems to play an important role in the causal relationship between metabolic syndrome, type 2 diabetes, and hyperuricemia. Oral diabetic drugs that would have additional beneficial effects on reducing serum uric acid levels are of importance. Selective SGLT2 inhibitors were extensively studied in type 2 diabetes mellitus and were found to have improvement of glycemic control, in addition to their proven metabolic effects on weight and blood pressure. Additional beneficial effect of SGLT2 inhibitors on serum uric acid level reduction is investigated. Recently, data have been accumulating showing that they have additional beneficial effects on serum uric acid reduction. As for the postulated mechanism, serum uric acid decreased in SGLT2 inhibitor users as a result of the increase in the urinary excretion rate of uric acid, due to the inhibition of uric acid reabsorption mediated by the effect of the drug on the GLUT9 isoform 2, located at the collecting duct of the renal tubule.
Torres, Allan M; Tsampazi, Chryssanthi; Geraghty, Dominic P; Bansal, Paramjit S; Alewood, Paul F; Kuchel, Philip W
2005-10-15
The recent discovery that the natriuretic peptide OvCNPb (Ornithorhynchus venom C-type natriuretic peptide B) from platypus (Ornithorynchus anatinus) venom contains a D-amino acid residue suggested that other D-amino-acid-containing peptides might be present in the venom. In the present study, we show that DLP-2 (defensin-like peptide-2), a 42-amino-acid residue polypeptide in the platypus venom, also contains a D-amino acid residue, D-methionine, at position 2, while DLP-4, which has an identical amino acid sequence, has all amino acids in the L-form. These findings were supported further by the detection of isomerase activity in the platypus gland venom extract that converts DLP-4 into DLP-2. In the light of this new information, the tertiary structure of DLP-2 was recalculated using a new structural template with D-Met2. The structure of DLP-4 was also determined in order to evaluate the effect of a D-amino acid at position 2 on the structure and possibly to explain the large retention time difference observed for the two molecules in reverse-phase HPLC. The solution structures of the DLP-2 and DLP-4 are very similar to each other and to the earlier reported structure of DLP-2, which assumed that all amino acids were in the L-form. Our results suggest that the incorporation of the D-amino acid at position 2 has minimal effect on the overall fold in solution.
Cadmium Alters the Concentration of Fatty Acids in THP-1 Macrophages.
Olszowski, Tomasz; Gutowska, Izabela; Baranowska-Bosiacka, Irena; Łukomska, Agnieszka; Drozd, Arleta; Chlubek, Dariusz
2018-03-01
Fatty acid composition of human immune cells influences their function. The aim of this study was to evaluate the effects of known toxicant and immunomodulator, cadmium, at low concentrations on levels of selected fatty acids (FAs) in THP-1 macrophages. The differentiation of THP-1 monocytes into macrophages was achieved by administration of phorbol myristate acetate. Macrophages were incubated with various cadmium chloride (CdCl 2 ) solutions for 48 h at final concentrations of 5 nM, 20 nM, 200 nM, and 2 μM CdCl 2 . Fatty acids were extracted from samples according to the Folch method. The fatty acid levels were determined using gas chromatography. The following fatty acids were analyzed: long-chain saturated fatty acids (SFAs) palmitic acid and stearic acid, very long-chain saturated fatty acid (VLSFA) arachidic acid, monounsaturated fatty acids (MUFAs) palmitoleic acid, oleic acid and vaccenic acid, and n-6 polyunsaturated fatty acids (PUFAs) linoleic acid and arachidonic acid. Treatment of macrophages with very low concentrations of cadmium (5-200 nM) resulted in significant reduction in the levels of arachidic, palmitoleic, oleic, vaccenic, and linoleic acids and significant increase in arachidonic acid levels (following exposure to 5 nM Cd), without significant reduction of palmitic and stearic acid levels. Treatment of macrophages with the highest tested cadmium concentration (2 μM) produced significant reduction in the levels of all examined FAs: SFAs, VLSFA, MUFAs, and PUFAs. In conclusion, cadmium at tested concentrations caused significant alterations in THP-1 macrophage fatty acid levels, disrupting their composition, which might dysregulate fatty acid/lipid metabolism thus affecting macrophage behavior and inflammatory state.
Studenroth, Sabine; Huber, Stefan G; Kotte, Karsten; Schöler, Heinz F
2013-02-05
Oxalic acid is the smallest dicarboxylic acid and plays an important role in soil processes (e.g., mineral weathering and metal detoxification in plants). We have first proven its abiotic formation in soils and investigated natural abiotic degradation processes based on the oxidation of soil organic matter, enhanced by Fe(3+) and H(2)O(2) as hydroxyl radical suppliers. Experiments with the model compound catechol and further hydroxylated benzenes were performed to examine a common degradation pathway and to presume a general formation mechanism of oxalic acid. Two soil samples were tested for the release of oxalic acid and the potential effects of various soil parameters on oxalic acid formation. Additionally, the soil samples were treated with different soil sterilization methods to prove the oxalic acid formation under abiotic soil conditions. Different series of model experiments were conducted to determine a range of factors including Fe(3+), H(2)O(2), reaction time, pH, and chloride concentration on oxalic acid formation. Under certain conditions, catechol is degraded up to 65.6% to oxalic acid referring to carbon. In serial experiments with two soil samples, oxalic acid was produced, and the obtained results are suggestive of an abiotic degradation process. In conclusion, Fenton-like conditions with low Fe(3+) concentrations and an excess of H(2)O(2) as well as acidic conditions were required for an optimal oxalic acid formation. The presence of chloride reduced oxalic acid formation.
Russell, Heidi V.; Groshen, Susan G.; Ara, Tasnim; DeClerck, Yves A.; Hawkins, Randy; Jackson, Hollie A.; Daldrup-Link, Heike E.; Marachelian, Araz; Skerjanec, Andrej; Park, Julie R.; Katzenstein, Howard; Matthay, Katherine K.; Blaney, Susan M.; Villablanca, Judith G.
2010-01-01
Background Zoledronic acid, a bisphosphonate, delays progression of bone metastases in adult malignancies. Bone is a common metastatic site of advanced neuroblastoma. We previously reported efficacy of zoledronic acid in a murine model of neuroblastoma bone invasion prompting this Phase I trial of zoledronic acid with cyclophosphamide in children with neuroblastoma and bone metastases. The primary objective was to determine recommended dosing of zoledronic acid for future trials. Procedure Escalating doses of intravenous zoledronic acid were given every 28 days with oral metronomic cyclophosphamide (25 mg/m2/day). Toxicity, response, zoledronic acid pharmacokinetics, bone turnover markers, serum IL-6, and sIL-6R were evaluated. Results Twenty-one patients, median age 7.5 (range 0.8 - 25.6) years were treated with 2 mg/m2 (n=4), 3 mg/m2 (n=3), or 4 mg/m2 (n=14) zoledronic acid. Fourteen patients were evaluable for dose escalation. A median of one (range 1-18) courses was given. Two dose limiting toxicities (Grade 3 hypophosphatemia) occurred at 4 mg/m2 zoledronic acid. Other Grade 3-4 toxicities included hypocalcemia (n=2), elevated transaminases (n=1), neutropenia (n=2), anemia (n=1), lymphopenia (n=1), and hypokalemia (n=1). Osteosclerosis contributed to fractures in one patient after 18 courses. Responses in evaluable patients included 1 partial response, 9 stable disease (median 4.5 courses, range 3-18), and 10 progressions. Zoledronic acid pharmacokinetics were similar to adults. Markers of osteoclast activity and serum IL-6 levels decreased with therapy. Conclusions Zoledronic acid with metronomic cyclophosphamide is well tolerated with clinical and biologic responses in recurrent/refractory neuroblastoma. The recommended dose of zoledronic acid is 4 mg/m2 every 28 days. PMID:21671363
Peterson, Eric C; Daugulis, Andrew J
2014-03-01
Production of organic acids in solid-liquid two-phase partitioning bioreactors (TPPBs) is challenging, and highly pH-dependent, as cell growth occurs near neutral pH, while acid sorption occurs only at low pH conditions. CO2 sparging was used to achieve acidic pH swings, facilitating undissociated organic acid uptake without generating osmotic stress inherent in traditional acid/base pH control. A modified cultivation medium was formulated to permit greater pH reduction by CO2 sparging (pH 4.8) compared to typical media (pH 5.3), while still possessing adequate nutrients for extensive cell growth. In situ product recovery (ISPR) of butyric acid (pKa = 4.8) produced by Clostridium tyrobutyricum was achieved through intermittent CO2 sparging while recycling reactor contents through a column packed with absorptive polymer Hytrel® 3078. This polymer was selected on the basis of its composition as a polyether copolymer, and the use of solubility parameters for predicting solute polymer affinity, and was found to have a partition coefficient for butyric acid of 3. Total polymeric extraction of 3.2 g butyric acid with no CO2 mediated pH swings was increased to 4.5 g via CO2 -facilitated pH shifting, despite the buffering capacity of butyric acid, which resists pH shifting. This work shows that CO2 -mediated pH swings have an observable positive effect on organic acid extraction, with improvements well over 150% under optimal conditions in early stage fermentation compared to CO2 -free controls, and this technique can be applied other organic acid fermentations to achieve or improve ISPR. © 2013 Wiley Periodicals, Inc.
Tognolini, Massimiliano; Incerti, Matteo; Mohamed, Iftiin Hassan; Giorgio, Carmine; Russo, Simonetta; Bruni, Renato; Lelli, Barbara; Bracci, Luisa; Noberini, Roberta; Pasquale, Elena B.; Barocelli, Elisabetta; Vicini, Paola; Mor, Marco
2012-01-01
The Eph–ephrin system, including the EphA2 receptor and the ephrin-A1 ligand, plays a critical role in tumor and vascular functions during carcinogenesis. We previously identified (3α,5β)-3-hydroxycholan-24-oic acid (lithocholic acid) as an Eph-ephrin antagonist able to inhibit EphA2 receptor activation and therefore potentially useful as a novel EphA2 receptor targeting agent. Here, we explore the structure-activity relationships of a focused set of lithocholic acid derivatives, based on molecular modelling investigation and displacement binding assays. Our exploration shows that while the 3-α-hydroxyl group of lithocholic acid has a negligible role in the recognition of the EphA2 receptor, its carboxylate group is critical for disrupting the binding of ephrin-A1 to the EphA2. As a result of our investigation, we identified (5β)-cholan-24-oic acid (cholanic acid) as a novel compound that competitively inhibits EphA2-ephrin-A1 interaction with higher potency than lithocholic acid. Surface plasmon resonance analysis indicates that cholanic acid binds specifically and reversibly to the ligand-binding domain of EphA2, with a steady-state dissociation constant (KD) in the low micromolar range. Furthermore, cholanic acid blocks the phosphorylation of EphA2 and cell retraction and rounding in PC3 prostate cancer cells, two effects that depend on EphA2 activation by the ephrin-A1 ligand. These findings suggest that cholanic acid can be used as a template structure to design effective EphA2 antagonists, with potential impact in the elucidation of the role played by this receptor in pathological conditions. PMID:22529030
Koh, Phil-Ok
2013-01-01
Background Ferulic acid provides a neuroprotective effect during cerebral ischemia through its anti-oxidant function. Protein phosphatase 2A (PP2A) is a serine and threonine phosphatase that contributes broadly to normal brain function. This study investigated whether ferulic acid regulates PP2A subunit B in a middle cerebral artery occlusion (MCAO) animal model and glutamate toxicity-induced neuronal cell death. Methodology/Principal Findings MCAO was surgically induced to yield permanent cerebral ischemic injury in rats. The rats were treated with either vehicle or ferulic acid (100 mg/kg, i.v.) immediately after MCAO, and cerebral cortex tissues were collected 24 h after MCAO. A proteomics approach, RT-PCR, and Western blot analyses performed to identification of PP2A subunit B expression levels. Ferulic acid significantly reduced the MCAO-induced infarct volume of the cerebral cortex. A proteomics approach elucidated the reduction of PP2A subunit B in MCAO-induced animals, and ferulic acid treatment prevented the injury-induced reduction in PP2A subunit B levels. RT-PCR and Western blot analyses also showed that ferulic acid treatment attenuates the injury-induced decrease in PP2A subunit B levels. Moreover, the number of PP2A subunit B-positive cells was reduced in MCAO-induced animals, and ferulic acid prevented these decreases. In cultured neuronal cells, ferulic acid treatment protected cells against glutamate toxicity and prevented the glutamate-induced decrease in PP2A subunit B. Conclusions/Significance These results suggest that the maintenance of PP2A subunit B by ferulic acid in ischemic brain injury plays an important role for the neuroprotective function of ferulic acid. PMID:23349830
NASA Astrophysics Data System (ADS)
Mahmoud, Hatem A.; Narasimharao, Katabathini; Ali, Tarek T.; Khalil, Kamal M. S.
2018-02-01
TiO2 nanoparticles were synthesized from titanium isopropoxide by a simple peptization method using sulfuric, nitric, and acetic acids. The effect of peptizing acid on physicochemical and photocatalytic properties of TiO2 powders was studied. The structural properties of synthesized TiO2 powders were analyzed by using XRD, TEM, N2-physisorption, Raman, DR UV- vis, FTIR, and X-ray photoelectron spectroscopy techniques. The characterization results showed that acetic acid peptization facilitated the formation of pure anatase phase after thermal treatment at 500 °C; in contrast, nitric acid peptization led to a major rutile phase formation (67%). Interestingly, the sample peptized using sulfuric acid yielded 95% anatase and 5% rutile phases. The photocatalytic activity of synthesized TiO2 nanoparticles was evaluated for degradation of selected organic dyes (crystal violet, methylene blue, and p-nitrophenol) in aqueous solution. The results confirmed that the TiO2 sample peptized using nitric acid (with rutile and anatase phases in 3:1 ratio) offered the highest activity for degradation of organic dyes, although, TiO2 samples peptized using sulfuric acid and acetic acid possessed smaller particle size, higher band gap energy, and high surface area. Interestingly, TiO2 sample peptized with nitric acid possessed relatively high theoretical photocurrent density (0.545 mAcm-2) and pore diameter (150 Å), which are responsible for high electron-hole separation efficiency and diffusion and mass transportation of organic reactants during the photochemical degradation process. The superior activity of TiO2 sample peptized with nitric acid is due to the effective transfer of photogenerated electrons between rutile and anatase phases.
The effects of hydroxy fatty acids on the hyphal branching of germinated spores of AM fungi.
Nagahashi, Gerald; Douds, David D
2011-01-01
Two hydroxy fatty acids, tentatively identified previously in carrot root exudates, were tested for their effects on hyphal growth of the arbuscular mycorrhizal (AM) fungus, Gigaspora gigantea (Nicol. and Gerd.) Gerdemann and Trappe. Best results were achieved with a long-term bioassay (7-8d) with nanomolar concentrations throughout the Petri dish in contrast to the rapid microinjection bioassay (16-24h) in which nanogram quantities were injected near growing hyphal tips. When 5nM 2-hydroxy fatty acids of various chain length were tested, the length of the hydroxyl fatty acid was significant since only 2-hydroxytetradecanoic acid (2OH-TDA) and to a slightly lesser degree, 2-hydroxydodecanoic acid (2OH-DDA) induced a hyphal growth response while 2-hydroxydecanoic acid (2OH-DA) and 2-hydroxyhexadecanoic (2OH-HDA) acid did not. The position of the hydroxyl group was critical since 5nM 3-hydroxytetradecanoic acid (3OH-TDA) had no effect on hyphal growth. The length of the non-hydroxy containing straight chain fatty acid, per se, did not appear significant since none of these fatty acids had an effect on hyphal growth. The morphological growth response promoted by 2OH-TDA consisted of multiple lateral branches, spaced fairly regularly apart, along the primary germ tubes as well as some lateral branch formation off the major secondary hyphae. This growth response was identical to that observed when germinated spores were allowed to grow towards cultured carrot roots in vitro. This response to 2OH-TDA also was observed with an unidentified Gigaspora species but no morphological response was observed with Glomus intraradices Schenck and Smith. The results indicate that 2-hydroxy fatty acids are another putative category of root exudate signals perceived by Gigaspora species, stimulating an increase in elongated lateral branches. Published by Elsevier Ltd.
NASA Astrophysics Data System (ADS)
Zhu, Cheng; Turner, Andrew M.; Abplanalp, Matthew J.; Kaiser, Ralf I.
2018-01-01
This laboratory study simulated the abiotic formation of carboxylic acids (RCOOH) in interstellar analogous ices of carbon dioxide (CO2) and methane (CH4) at 10 K upon exposure to energetic electrons. The chemical processing of the ices and the subsequent warm-up phase were monitored online and in situ, exploiting Fourier Transform Infrared Spectrometry and quadrupole mass spectrometry. Characteristic absorptions of functional groups of carboxylic acids (RCOOH) were observed in the infrared spectra of the irradiated ice. Two proposed reaction mechanisms replicated the kinetic profiles of the carboxylic acids along with the decay profile of the precursors during the irradiation via hydrocarbon formation, followed by carboxylation and/or through acetic acid along with mass growth processes of the alkyl chain. Mass spectra recorded during the warm-up phase demonstrated that these acids are distributed from acetic acid (CH3COOH) up to decanoic acid (C9H19COOH). High-dose irradiation studies (91 ± 14 eV) converted low-molecular-weight acids such as acetic acid (CH3COOH) and propionic acid (C2H5COOH) to higher-molecular-weight carboxylic acids, compared to low-dose irradiation studies (18 ± 3 eV). The traces of the {{{H}}}2{{C}}= {{C}}({OH}{)}2+ (m/z = 60) fragment—a link to linear carboxylic acids—implied that higher-order acids (C n H2n+1COOH, n ≥ 5) are likely branched, which correlates with the recent analysis of the structures of the monocarboxylic acids in the Murchison meteorite.
Code of Federal Regulations, 2014 CFR
2014-07-01
..., alkanediol,.alpha.-hydro-.omega.-hydroxypoly[oxyalkanediyl], 1,3-isobenzofurandione, methylene diphenyl...-ethanediol, alkanedioic acid, alkanediol,.alpha.-hydro-.omega.-hydroxypoly[oxyalkanediyl], 1,3... substituted alkanediol, dodecanedioic acid, 1,2-ethanediol, alkanedioic acid, alkanediol,.alpha.-hydro-.omega...
Fatty acid synthesis in Escherichia coli
Knivett, V. A.; Cullen, Julia
1967-01-01
1. Fatty acid formation by cells of a strain of Escherichia coli has been studied in the exponential, post-exponential and stationary phases of growth. 2. During the exponential phase of growth, the metabolic quotient (mμmoles of fatty acid synthesized/mg. dry wt. of cells/hr.) for each fatty acid in the extractable lipid was constant. 3. The newly synthesized fatty acid mixtures produced during this phase contained hexadecanoic acid (41%), hexadecenoic acid (31%), octadecenoic acid (21%) and the C17-cyclopropane acid, methylenehexadecanoic acid (4%). 4. As the proportion of newly synthesized material increased, changes in the fatty acid composition of the cells during this period were towards this constant composition. 5. Abrupt changes in fatty acid synthesis occurred when exponential growth ceased. 6. In media in which glycerol, or SO42− or Mg2+, was growth-limiting there was a small accumulation of C17-cyclopropane acid in cells growing in the post-exponential phase of growth. 7. Where either NH4+ or PO43− was growth-limiting and there were adequate supplies of glycerol, Mg2+ and SO42−, there was a marked accumulation of C17-cyclopropane acid and C19-cyclopropane acid appeared. 8. Under appropriate conditions the metabolic quotient for C17-cyclopropane acid increased up to sevenfold at the end of exponential growth. Simultaneously the metabolic quotients of the other acids fell. 9. A mixture of glycerol, Mg2+ and SO42− stimulated cyclopropane acid formation in resting cells. PMID:5340364
McGrath, John W; Hammerschmidt, Friedrich; Preusser, Werner; Quinn, John P; Schweifer, Anna
2009-05-07
The first step of the mineralisation of fosfomycin by R. huakuii PMY1 is hydrolytic ring opening with the formation of (1R,2R)-1,2-dihydroxypropylphosphonic acid. This phosphonic acid and its three stereoisomers were synthesised by chemical means and tested as their ammonium salts for mineralisation as evidenced by release of P(i). Only the (1R,2R)-isomer was degraded. A number of salts of phosphonic acids such as (+/-)-1,2-epoxybutyl-, (+/-)-1,2-dihydroxyethyl-, 2-oxopropyl-, (S)-2-hydroxypropyl-, (+/-)-1-hydroxypropyl- and (+/-)-1-hydroxy-2-oxopropylphosphonic acid were synthesised chemically, but none supported growth. In vitro C-P bond cleavage activity was however detected with the last phosphonic acid. A mechanism involving phosphite had to be discarded as it could not be used as a phosphorus source. R. huakuii PMY1 grew well on (R)- and (S)-lactic acid and hydroxyacetone, but less well on propionic acid and not on acetone or (R)- and (+/-)-1,2-propanediol. The P(i) released from (1R,2R)-1,2-dihydroxypropylphosphonic acid labelled with one oxygen-18 in the PO3H2 group did not stay long enough in the cells to allow complete exchange of 18O for 16O by enzymic turnover.
BenSaad, Lamees A; Kim, Kah Hwi; Quah, Chin Chew; Kim, Wee Ric; Shahimi, Mustafa
2017-01-14
Punica granatum (pomegranate), an edible fruit originating in the Middle East, has been used as a traditional medicine for treatment of pain and inflammatory conditions such as peptic ulcer. The numerous risks associated with nonsteroidal anti-inflammatory drugs (NSAIDs) for treatment of pain and inflammation give rise to using medicinal herbs as alternative therapies. This study aimed to evaluate the anti-inflammatory effect of isolated compounds from the ethyl acetate (EtOAc) fraction of P. granatum by determination of their inhibitory effects on lipopolysaccharide (LPS), stimulated nitric oxide (NO), prostaglandin E2 (PGE-2), interleukin-6 (IL-6) and cyclooxxgenase-2 (COX-2) release from RAW264.7 cells. The compounds ellagic acid, gallic acid and punicalagin A&B were isolated from EtOAc by high performance liquid chromatography (HPLC) and further identified by mass spectrometry (MS). The inhibitory effect of ellagic acid, gallic acid and punicalagin A&B were evaluated on the production of LPS-induced NO by Griess reagent, PGE-2 and IL-6 by immunoassay kit and prostaglandin E2 competitive ELISA kit, and COX-2 by Western blotting. Ellagic acid, gallic acid and punicalagin A&B potentially inhibited LPS-induced NO, PGE-2 and IL-6 production. The results indicate that ellagic acid, gallic acid and punicalagin may be the compounds responsible for the anti-inflammatory potential of P. granatum.
Ma, Dongyun; Li, Yaoguang; Zhang, Jian; Wang, Chenyang; Qin, Haixia; Ding, Huina; Xie, Yingxin; Guo, Tiancai
2016-01-01
Polyphenols in whole grain wheat have potential health benefits, but little is known about the expression patterns of phenolic acid biosynthesis genes and the accumulation of phenolic acid compounds in different-colored wheat grains. We found that purple wheat varieties had the highest total phenolic content (TPC) and antioxidant activity. Among phenolic acid compounds, bound ferulic acid, vanillic, and caffeic acid levels were significantly higher in purple wheat than in white and red wheat, while total soluble phenolic acid, soluble ferulic acid, and vanillic acid levels were significantly higher in purple and red wheat than in white wheat. Ferulic acid and syringic acid levels peaked at 14 days after anthesis (DAA), whereas p-coumaric acid and caffeic acid levels peaked at 7 DAA, and vanillic acid levels gradually increased during grain filling and peaked near ripeness (35 DAA). Nine phenolic acid biosynthesis pathway genes (TaPAL1, TaPAL2, TaC3H1, TaC3H2, TaC4H, Ta4CL1, Ta4CL2, TaCOMT1, and TaCOMT2) exhibited three distinct expression patterns during grain filling, which may be related to the different phenolic acids levels. White wheat had higher phenolic acid contents and relatively high gene expression at the early stage, while purple wheat had the highest phenolic acid contents and gene expression levels at later stages. These results suggest that the expression of phenolic acid biosynthesis genes may be closely related to phenolic acids accumulation.
Ma, Dongyun; Li, Yaoguang; Zhang, Jian; Wang, Chenyang; Qin, Haixia; Ding, Huina; Xie, Yingxin; Guo, Tiancai
2016-01-01
Polyphenols in whole grain wheat have potential health benefits, but little is known about the expression patterns of phenolic acid biosynthesis genes and the accumulation of phenolic acid compounds in different-colored wheat grains. We found that purple wheat varieties had the highest total phenolic content (TPC) and antioxidant activity. Among phenolic acid compounds, bound ferulic acid, vanillic, and caffeic acid levels were significantly higher in purple wheat than in white and red wheat, while total soluble phenolic acid, soluble ferulic acid, and vanillic acid levels were significantly higher in purple and red wheat than in white wheat. Ferulic acid and syringic acid levels peaked at 14 days after anthesis (DAA), whereas p-coumaric acid and caffeic acid levels peaked at 7 DAA, and vanillic acid levels gradually increased during grain filling and peaked near ripeness (35 DAA). Nine phenolic acid biosynthesis pathway genes (TaPAL1, TaPAL2, TaC3H1, TaC3H2, TaC4H, Ta4CL1, Ta4CL2, TaCOMT1, and TaCOMT2) exhibited three distinct expression patterns during grain filling, which may be related to the different phenolic acids levels. White wheat had higher phenolic acid contents and relatively high gene expression at the early stage, while purple wheat had the highest phenolic acid contents and gene expression levels at later stages. These results suggest that the expression of phenolic acid biosynthesis genes may be closely related to phenolic acids accumulation. PMID:27148345
Novel Three-Component Phenazine-1-Carboxylic Acid 1,2-Dioxygenase in Sphingomonas wittichii DP58
Zhao, Qiang; Wang, Wei; Huang, Xian-Qing; Zhang, Xue-Hong
2017-01-01
ABSTRACT Phenazine-1-carboxylic acid, the main component of shenqinmycin, is widely used in southern China for the prevention of rice sheath blight. However, the fate of phenazine-1-carboxylic acid in soil remains uncertain. Sphingomonas wittichii DP58 can use phenazine-1-carboxylic acid as its sole carbon and nitrogen sources for growth. In this study, dioxygenase-encoding genes, pcaA1A2, were found using transcriptome analysis to be highly upregulated upon phenazine-1-carboxylic acid biodegradation. PcaA1 shares 68% amino acid sequence identity with the large oxygenase subunit of anthranilate 1,2-dioxygenase from Rhodococcus maanshanensis DSM 44675. The dioxygenase was coexpressed in Escherichia coli with its adjacent reductase-encoding gene, pcaA3, and ferredoxin-encoding gene, pcaA4, and showed phenazine-1-carboxylic acid consumption. The dioxygenase-, ferredoxin-, and reductase-encoding genes were expressed in Pseudomonas putida KT2440 or E. coli BL21, and the three recombinant proteins were purified. A phenazine-1-carboxylic acid conversion capability occurred in vitro only when all three components were present. However, P. putida KT2440 transformed with pcaA1A2 obtained phenazine-1-carboxylic acid degradation ability, suggesting that phenazine-1-carboxylic acid 1,2-dioxygenase has low specificities for its ferredoxin and reductase. This was verified by replacing PcaA3 with RedA2 in the in vitro enzyme assay. High-performance liquid chromatography–mass spectrometry (HPLC-MS) and nuclear magnetic resonance (NMR) analysis showed that phenazine-1-carboxylic acid was converted to 1,2-dihydroxyphenazine through decarboxylation and hydroxylation, indicating that PcaA1A2A3A4 constitutes the initial phenazine-1-carboxylic acid 1,2-dioxygenase. This study fills a gap in our understanding of the biodegradation of phenazine-1-carboxylic acid and illustrates a new dioxygenase for decarboxylation. IMPORTANCE Phenazine-1-carboxylic acid is widely used in southern China as a key fungicide to prevent rice sheath blight. However, the degradation characteristics of phenazine-1-carboxylic acid and the environmental consequences of the long-term application are not clear. S. wittichii DP58 can use phenazine-1-carboxylic acid as its sole carbon and nitrogen sources. In this study, a three-component dioxygenase, PcaA1A2A3A4, was determined to be the initial dioxygenase for phenazine-1-carboxylic acid degradation in S. wittichii DP58. Phenazine-1-carboxylic acid was converted to 1,2-dihydroxyphenazine through decarboxylation and hydroxylation. This finding may help us discover the pathway for phenazine-1-carboxylic acid degradation. PMID:28188209
Physicochemical properties and analysis of Malaysian palm fatty acid distilled
NASA Astrophysics Data System (ADS)
Jumaah, Majd Ahmed; Yusoff, Mohamad Firdaus Mohamad; Salimon, Jumat
2018-04-01
Palm fatty acid distillate (PFAD) is cheap and valuable byproduct of edible oil processing industries. This study was carried out to determine the physicochemical properties of Malaysian palm fatty acid distilled (PFAD). The physicochemical properties showed that the free fatty acid (FFA %), acid value, iodine value, saponification value, unsaponifiable matter, hydroxyl value, specific gravity at 28°C, moisture content, viscosity at 40°C and colour at 28°C values were 87.04± 0.1 %, 190.6± 1 mg/g, 53.3±0.2 mg/g, 210.37±0.8 mg/g, 1.5±0.1%, 47±0.2 mg/g, 0.87 g/ml, 0.63 %, 30 cSt and yellowish respectively. Gas chromatography (GC) was used to determine the fatty acid (FA) composition in PFAD. The fatty acids were found to be comprised mostly with 48.9 % palmitic acid (C16:0), 37.4 % oleic acid (C18:1), 9.7 % linoleic acid (C18:2), 2.7 % stearic acid (C18:0) and 1.1 % myristic acid (C14:0). The analysis of high performance liquid chromatography (HPLC) has resulted with 99.2 % of FFA, while diacylglycerol and monoacylglycerol were 0.69 and 0.062 % respectively.
2-Keto acids based biosynthesis pathways for renewable fuels and chemicals.
Tashiro, Yohei; Rodriguez, Gabriel M; Atsumi, Shota
2015-03-01
Global energy and environmental concerns have driven the development of biological chemical production from renewable sources. Biological processes using microorganisms are efficient and have been traditionally utilized to convert biomass (i.e., glucose) to useful chemicals such as amino acids. To produce desired fuels and chemicals with high yield and rate, metabolic pathways have been enhanced and expanded with metabolic engineering and synthetic biology approaches. 2-Keto acids, which are key intermediates in amino acid biosynthesis, can be converted to a wide range of chemicals. 2-Keto acid pathways were engineered in previous research efforts and these studies demonstrated that 2-keto acid pathways have high potential for novel metabolic routes with high productivity. In this review, we discuss recently developed 2-keto acid-based pathways.
Amakura, Yoshiaki; Yoshimura, Morio; Morimoto, Sara; Yoshida, Takashi; Tada, Atsuko; Ito, Yusai; Yamazaki, Takeshi; Sugimoto, Naoki; Akiyama, Hiroshi
2016-01-01
Gentian root extract is used as a bitter food additive in Japan. We investigated the constituents of this extract to acquire the chemical data needed for standardized specifications. Fourteen known compounds were isolated in addition to a mixture of gentisin and isogentisin: anofinic acid, 2-methoxyanofinic acid, furan-2-carboxylic acid, 5-hydroxymethyl-2-furfural, 2,3-dihydroxybenzoic acid, isovitexin, gentiopicroside, loganic acid, sweroside, vanillic acid, gentisin 7-O-primeveroside, isogentisin 3-O-primeveroside, 6'-O-glucosylgentiopicroside, and swertiajaposide D. Moreover, a new compound, loganic acid 7-(2'-hydroxy-3'-O-β-D-glucopyranosyl)benzoate (1), was also isolated. HPLC was used to analyze gentiopicroside and amarogentin, defined as the main constituents of gentian root extract in the List of Existing Food Additives in Japan.
Morita, N; Shibahara, A; Yamamoto, K; Shinkai, K; Kajimoto, G; Okuyama, H
1993-02-01
Vibrio sp. strain ABE-1 was grown in a medium that contained as its stable isotope tracer either [2,2-2H2]cis-9-hexadecenoic or [2,2-2H2]trans-9-hexadecenoic acid. Gas chromatographic-mass spectrometric analysis of the cis-9-hexadecenoic and trans-9-hexadecenoic acid fractions from the cells revealed the formation of an intracellularly isomerized 2,2-2H2-fatty acid which differed from the tracer only in the geometrical configuration of the double bond. This observation shows that cis-trans isomerization without a shift in double-bond position between these two geometric hexadecenoic acid isomers can occur in the cells.
Morita, N; Shibahara, A; Yamamoto, K; Shinkai, K; Kajimoto, G; Okuyama, H
1993-01-01
Vibrio sp. strain ABE-1 was grown in a medium that contained as its stable isotope tracer either [2,2-2H2]cis-9-hexadecenoic or [2,2-2H2]trans-9-hexadecenoic acid. Gas chromatographic-mass spectrometric analysis of the cis-9-hexadecenoic and trans-9-hexadecenoic acid fractions from the cells revealed the formation of an intracellularly isomerized 2,2-2H2-fatty acid which differed from the tracer only in the geometrical configuration of the double bond. This observation shows that cis-trans isomerization without a shift in double-bond position between these two geometric hexadecenoic acid isomers can occur in the cells. PMID:8423164
Carballeira, N M; Emiliano, A; Hernández-Alonso, N; González, F A
1998-12-01
The total synthesis of the naturally occurring (Z)-2-methoxy-5-hexadecenoic acid and (Z)-2-methoxy-6-hexadecenoic acid was accomplished using as a key step Mukaiyama's trimethylsilyl cyanide addition to 4- and 5-pentadecenal, respectively. These syntheses further confirm the structures of the natural marine fatty acids and corroborate their cis double-bond stereochemistry. The title compounds were antimicrobial against the Gram-positive bacteria Staphylococcus aureus (MIC 0.35 micromol/mL) and Streptococcus faecalis (MIC 0.35 micromol/mL).
Code of Federal Regulations, 2011 CFR
2011-07-01
... 40 Protection of Environment 31 2011-07-01 2011-07-01 false Benzoic acid, 3-amino-, diazotized, coupled with 6-amino-4-hydroxy-2-naphthalenesulfonic acid, diazotized, (3-aminophenyl)phosphonic acid and... Significant New Uses for Specific Chemical Substances § 721.1705 Benzoic acid, 3-amino-, diazotized, coupled...
Code of Federal Regulations, 2010 CFR
2010-07-01
... 40 Protection of Environment 30 2010-07-01 2010-07-01 false Benzoic acid, 3-amino-, diazotized, coupled with 6-amino-4-hydroxy-2-naphthalenesulfonic acid, diazotized, (3-aminophenyl)phosphonic acid and... Significant New Uses for Specific Chemical Substances § 721.1705 Benzoic acid, 3-amino-, diazotized, coupled...
Code of Federal Regulations, 2010 CFR
2010-07-01
...-hydroxyethyl ester, reaction products with hexakis(alkoxyalkyl)melamine (generic). 721.10136 Section 721.10136... 2-Propenoic acid, 2-methyl-, 2-hydroxyethyl ester, reaction products with hexakis(alkoxyalkyl... substance identified generically as 2-propenoic acid, 2-methyl-, 2-hydroxyethyl ester, reaction products...
Code of Federal Regulations, 2011 CFR
2011-07-01
...-hydroxyethyl ester, reaction products with hexakis(alkoxyalkyl)melamine (generic). 721.10136 Section 721.10136... 2-Propenoic acid, 2-methyl-, 2-hydroxyethyl ester, reaction products with hexakis(alkoxyalkyl... substance identified generically as 2-propenoic acid, 2-methyl-, 2-hydroxyethyl ester, reaction products...
The Path of Carbon in Photosynthesis II. Amino Acids
DOE R&D Accomplishments Database
Stepka, W.; Benson, A. A.; Calvin, M.
1948-05-25
The radioactive amino acid's synthesized from C{sup 14}O{sub 2} by green algae both in the light and in the dark after CO{sub 2}-free preillumination have been separated and identified using paper chromatography and radioautography. The radioactive amino acids identified were aspartic acid, alanine and smaller amounts of 3- and 4-carbon amino acids. This finding as well as the total absence of radioactive glutamic acid substantiates the mechanism for reduction of CO{sub 2} previously postulated by members of this laboratory.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Meyer, Matthew M; Wang, Xue B; Reed, Christopher A
2009-12-23
Five CHB 11X 6Y 5 - carborane anions from the series X = Br, Cl, I and Y = H, Cl, CH 3 were generated by electrospray ionization, and their reactivity with a series of Brønsted acids and electron transfer reagents were examined in the gas phase. The undecachlorocarborane acid, H(CHB 11Cl 11), was found to be far more acidic than the former record holder, (1-C 4F 9SO 2) 2NH (i.e., ΔH° acid = 241 ± 29 vs 291.1 ± 2.2 kcal mol -1) and bridges the gas-phase acidity and basicity scales for the first time. Its conjugate base, CHBmore » 11Cl 11 -, was found by photoelectron spectroscopy to have a remarkably large electron binding energy (6.35 ± 0.02 eV) but the value for the (1-C 4F 9SO 2) 2N - anion is even larger (6.5 ± 0.1 eV). Consequently, it is the weak H-(CHB 11Cl 11) BDE (70.0 kcal mol -1, G3(MP2)) compared to the strong BDE of (1-C 4F 9SO 2) 2N-H (127.4 ± 3.2 kcal mol -1) that accounts for the greater acidity of carborane acids.« less
Xin, Guobin; Tan, Jiayi; Yao, Lijuan; Zhu, Yu; Jiang, Zhaolin; Song, Hui
2008-01-01
A method for the determination of three phenoxyalkanoic acid herbicides, 2,4-dichlorophenoxyacetic acid (2,4-D), 2-(2,4-dichlorophenoxy)-propanoic acid (2,4-DP), and 4-chloro-2-methylphenoxy-acetic acid (MCPA), in blood was developed. The blood sample was diluted with 0.1 mol/L hydrochloric acid, and extracted by solid-phase extraction using porous resin GDX401 as adsorbent and ethyl ether as eluent. The extract was esterified with dichloropropanol in the presence of sulfuric acid as catalyst. The derivatives were analysed by gas chromatography with electron-capture detection. The detection limits of 2,4-D, 2,4-DP and MCPA were 20, 8 and 40 ng/mL, respectively. In quantitative analysis, 2,4-dichlorophenylacetic acid was used as an internal standard. The linear relationships and recoveries were satisfactory. The derivatization of the three herbicides with methanol, ethanol, n-propanol, n-butanol, and trifluoroethanol were also studied, and the analytical methods of these derivatization were compared with that of dichloropropanol as esterifying agent. The method is sensitive enough for the examination of the poison samples in actual.
Liu, Quan-Yu; Chen, Yong-Sheng; Wang, Fei; Chen, Shi-Wu; Zhang, Yong-Hong
2014-06-01
A new steroidal ester, beta-rosaterol palmitate (1) along with ten known compounds, uvaol(2), 3-epi-ursolic acid (3), 2alpha, 3beta, 24-trihydroxyolean-12-en-28-oic acid (4), 2alpha, 3alpha, 24-trihydroxyurs-12-en-28-oic acid (5), 2alpha, 3alpha, 24-trihydroxyolean-12-en-28-oic acid (6), 2alpha, 3alpha, 24-trihydroxyolean-12-en-28-oic acid-28-O-beta-D-glucopyranosyl ester (7), (Z)-9-hexadecenoic acid (8), octacosyl alcohol (9), beta-sitosterol (10) and beta-daucosterol (11), has been isolated from the stems and leaves of Vitex trifolia. Their structures were elucidated using a combination of 1D and 2D NMR techniques (COSY, HMQC, and HMBC)and HR-ESI-MS analyses. Compounds 2-7 were isolated from this plant for the first time.
Sharp, Stephen J.; Kröger, Janine; Griffin, Julian L.; Sluijs, Ivonne; Agudo, Antonio; Ardanaz, Eva; Balkau, Beverley; Boeing, Heiner; Chajes, Veronique; Dow, Courtney; Fagherazzi, Guy; Feskens, Edith J. M.; Franks, Paul W.; Gavrila, Diana; Gunter, Marc; Kaaks, Rudolf; Key, Timothy J.; Khaw, Kay-Tee; Kühn, Tilman; Melander, Olle; Molina-Portillo, Elena; Nilsson, Peter M.; Olsen, Anja; Overvad, Kim; Palli, Domenico; Panico, Salvatore; Rolandsson, Olov; Sieri, Sabina; Slimani, Nadia; Spijkerman, Annemieke M. W.; Tjønneland, Anne; Langenberg, Claudia; Riboli, Elio
2017-01-01
Background Combinations of multiple fatty acids may influence cardiometabolic risk more than single fatty acids. The association of a combination of fatty acids with incident type 2 diabetes (T2D) has not been evaluated. Methods and findings We measured plasma phospholipid fatty acids by gas chromatography in 27,296 adults, including 12,132 incident cases of T2D, over the follow-up period between baseline (1991–1998) and 31 December 2007 in 8 European countries in EPIC-InterAct, a nested case-cohort study. The first principal component derived by principal component analysis of 27 individual fatty acids (mole percentage) was the main exposure (subsequently called the fatty acid pattern score [FA-pattern score]). The FA-pattern score was partly characterised by high concentrations of linoleic acid, stearic acid, odd-chain fatty acids, and very-long-chain saturated fatty acids and low concentrations of γ-linolenic acid, palmitic acid, and long-chain monounsaturated fatty acids, and it explained 16.1% of the overall variability of the 27 fatty acids. Based on country-specific Prentice-weighted Cox regression and random-effects meta-analysis, the FA-pattern score was associated with lower incident T2D. Comparing the top to the bottom fifth of the score, the hazard ratio of incident T2D was 0.23 (95% CI 0.19–0.29) adjusted for potential confounders and 0.37 (95% CI 0.27–0.50) further adjusted for metabolic risk factors. The association changed little after adjustment for individual fatty acids or fatty acid subclasses. In cross-sectional analyses relating the FA-pattern score to metabolic, genetic, and dietary factors, the FA-pattern score was inversely associated with adiposity, triglycerides, liver enzymes, C-reactive protein, a genetic score representing insulin resistance, and dietary intakes of soft drinks and alcohol and was positively associated with high-density-lipoprotein cholesterol and intakes of polyunsaturated fat, dietary fibre, and coffee (p < 0.05 each). Limitations include potential measurement error in the fatty acids and other model covariates and possible residual confounding. Conclusions A combination of individual fatty acids, characterised by high concentrations of linoleic acid, odd-chain fatty acids, and very long-chain fatty acids, was associated with lower incidence of T2D. The specific fatty acid pattern may be influenced by metabolic, genetic, and dietary factors. PMID:29020051
DOE Office of Scientific and Technical Information (OSTI.GOV)
El-Gowelli, Hanan M., E-mail: dr_Hanan_el_gowali@hotmail.com; Saad, Evan I.; Abdel-Galil, Abdel-Galil A.
In this work, α-lipoic acid and cyclosporine demonstrated significant protection against acetic acid-induced ulcerative colitis in rats. We proposed that α-lipoic acid and cyclosporine co-administration might modulate their individual effects. Induction of ulcerative colitis in rats was performed by intra-rectal acetic acid (5% v/v) administration for 3 consecutive days. Effects of individual or combined used of α-lipoic acid (35 mg/kg ip) or cyclosporine (5 mg/kg sc) for 6 days starting 2 days prior to acetic acid were assessed. Acetic acid caused colon ulceration, bloody diarrhea and weight loss. Histologically, there was mucosal atrophy and inflammatory cells infiltration in submucosa, associatedmore » with depletion of colon reduced glutathione, superoxide dismutase and catalase activities and elevated colon malondialdehyde, serum C-reactive protein (C-RP) and tumor necrosis factor-α (TNF-α). Colon gene expression of cyclooxygenase-2 and miR-210 was also elevated. These devastating effects of acetic acid were abolished upon concurrent administration of α-lipoic acid. Alternatively, cyclosporine caused partial protection against acetic acid-induced ulcerative colitis. Cyclosporine did not restore colon reduced glutathione, catalase activity, serum C-RP or TNF-α. Unexpectedly, co-administration of α-lipoic acid and cyclosporine aggravated colon ulceration. Concomitant use of α-lipoic acid and cyclosporine significantly increased nitric oxide production, cyclooxygenase-2 and miR-210 gene expression compared to all other studied groups. The current findings suggest that facilitation of nitric oxide/cyclooxygenase-2/miR-210 cascade constitutes, at least partially, the cellular mechanism by which concurrent use of α-lipoic acid and cyclosporine aggravates colon damage. Collectively, the present work highlights the probable risk of using α-lipoic acid/cyclosporine combination in ulcerative colitis patients. - Highlights: • Lipoic acid is more effective than cyclosporine in protection against colitis. • Lipoic acid elevates colon antioxidant defensive mechanism and reduces inflammation. • Co-administration of lipoic acid and cyclosporine aggravates colon damage. • NO/COX-2/miR-210 elevations mediate cyclosporine–lipoic acid interaction.« less
Zhang, Bo-Wei; Xing, Yan; Wen, Chen; Yu, Xiao-Xia; Sun, Wen-Long; Xiu, Zhi-Long; Dong, Yue-Sheng
2017-11-15
In this paper, the inhibition of α-amylase and α-glucosidase by nine pentacyclic triterpenes was determined. For α-amylase inhibitory activity, the IC 50 values of ursolic acid, corosolic acid, and oleanolic acid were 22.6±2.4μM, 31.2±3.4μM, and 94.1±6.7μM, respectively. For α-glucosidase inhibition, the IC 50 values of ursolic acid, corosolic acid, betulinic acid, and oleanolic acid were 12.1±1.0μM, 17.2±0.9μM, 14.9±1.9μM, and 35.6±2.6μM, respectively. The combination of corosolic acid and oleanolic acid with acarbose showed synergistic inhibition against α-amylase. The combination of the tested triterpenes with acarbose mainly exhibited additive inhibition against α-glucosidase. Kinetic studies revealed that corosolic acid and oleanolic acid showed non-competitive inhibition and acarbose showed mixed-type inhibition against α-amylase. The results provide valuable implications for the triterpenes (ursolic acid, corosolic acid, and oleanolic acid) alone or in combination with acarbose as a therapeutic agent for the treatment of diabetes mellitus. Copyright © 2017 Elsevier Ltd. All rights reserved.
Shi, Jianghua; Lang, Chunxiu; Wang, Fulin; Wu, Xuelong; Liu, Renhu; Zheng, Tao; Zhang, Dongqing; Chen, Jinqing; Wu, Guanting
2017-10-01
In plants, the enzymes fatty acid dehydrogenase 2 (FAD2) and fatty acid elongase 1 (FAE1) have been shown in previous studies to play important roles in the de novo biosynthesis of fatty acids. However, the effects of depressed expression of FAD2 and FAE1 on seed storage compounds accumulation remains to be elucidated. In this study, we produced RNA interfering transgenic rapeseeds lines, BnFAD2-Ri, BnFAE1-Ri and BnFAD2/BnFAE1-Ri, which exhibited depressed expression of the BnFAD2 and BnFAE1 genes under the control of seed-specific napin A promoter. These transgenic rapeseeds showed normal growth and development as compared with the wild type (CY2). Depressed expression of BnFAD2 and BnFAE1 genes modified fatty acid profiles, leading to increased oleic acid and decreased erucic acid contents in transgenic seeds. Consistent with these results, the ratios of C18:1/C18:2 and C18:1/C18:3 in C18 unsaturated fatty acids were greatly increased due to increased oleic acid content in transgenic seeds. Moreover, depressed expression of BnFAD2 and BnFAE1 genes resulted in slightly decreased oil contents and increased protein contents in transgenic seeds. Our results demonstrated that depressed expression of BnFAD2 and BnFAE1 greatly improves seed nutritional quality by modulating the fatty acid metabolism and storage products accumulation and that BnFAD2 and BnFAE1 are reliable targets for genetic improvement of rapeseed in seed nutritional quality. Copyright © 2017 Elsevier B.V. All rights reserved.
Dicarboxylic acids generated by thermal alteration of kerogen and humic acids
NASA Technical Reports Server (NTRS)
Kawamura, Kimitaka; Kaplan, I. R.
1987-01-01
Significant amounts (up to 2 percent of organic geopolymers) of low-molecular-weight (LMW) dicarboxylic acids (C2-C10) have been detected during thermal alteration (270 C, 2 h) of kerogens and humic acids isolated from young or ancient lithified sediments. Their distribution is characterized by the predominance of oxalic acid followed by succinic, fumaric, and methylsuccinic acids. These acids are probably released by the breakdown of macromolecular structures, which have incorporated biogenic organic compounds, including diacids, during early digenesis in sediments. Because of their reactivity, LMW diacids may play geochemically important roles under natural conditions.
Determination of Perfluorocarboxylic Acids in Sludge
Methods were developed for the extraction from wastewater-treatment sludge and quantitation by LC/MS/MS of perfluorocarboxylic acids (PFCAs, C6 to C12), 7-3 fluorotelomer carboxylic acid (7-3 FTCA) and 8-2 fluorotelomer 2-unsaturated carboxylic acid (8-2 FTUCA) using LC/MS/MS.
NASA Astrophysics Data System (ADS)
Meng, Jingjing; Wang, Gehui; Li, Jianjun; Cheng, Chunlei; Cao, Junji
2013-11-01
Summertime PM2.5 aerosols collected from Qinghai Lake (3200 m a.s.l.), a remote continental site in the northeastern part of Tibetan Plateau, were analyzed for dicarboxylic acids (C2-C11), ketocarboxylic acids and α-dicarbonyals. Oxalic acid (C2) is the dominant dicarboxylic acid in the samples, followed by malonic, succinic and azelaic acids. Total dicarboxylic acids (231 ± 119 ng m-3), ketocarboxylic acids (8.4 ± 4.3 ng m-3), and α-dicarbonyls (2.7 ± 2.1 ng m-3) at the Tibetan background site are 2-5 times less than those detected in lowland areas such as 14 Chinese megacities. Compared to those in other urban and marine areas enhancements in relative abundances of C2/total diacids and diacids-C/WSOC of the PM2.5 samples suggest that organic aerosols in the region are more oxidized due to strong solar radiation. Molecular compositions and air mass trajectories demonstrate that the above secondary organic aerosols in the Qinghai Lake atmosphere are largely derived from long-range transport. Ratios of oxalic acid, glyoxal and methylglyoxal to levoglucosan in PM2.5 aerosols emitted from household burning of yak dung, a major energy source for Tibetan in the region, are 30-400 times lower than those in the ambient air, which further indicates that primary emission from biomass burning is a negligible source of atmospheric oxalic acid and α-dicarbonyls at this background site.
Synthesis and antioxidant properties of a new lipophilic ascorbic acid analogue.
Cotelle, Philippe; Cotelle, Nicole; Teissier, Elisabeth; Vezin, Hervé
2003-03-20
4-(4-Hydroxyphenyl)-5-(4-hydroxyphenylmethyl)-2-hydroxyfurane-2-one 1 was prepared by an acidic dimerisation of 4-hydroxyphenylpyruvic acid and some of its antioxidant and spectroscopic properties have been measured and compared to that of ascorbic acid. 1 is as good an antioxidant as ascorbic acid in the DPPH (2,2-diphenyl-1-picryl hydrazyl radical) test and the inhibition of hydroxyl radical and a powerful inhibitor of the Cu(2+) or AAPH (2,2'-azobis-(2-amidinopropane) dihydrochloride) induced oxidation of human LDL. 1 gives a stable radical characterised by its ESR spectrum similarly to ascorbic acid but in lower concentration and with a different reactivity towards nitroxides. Theoretical calculations allow us to propose the structure for the radical formed from 1, to explain its lower stability than ascorbyl radical and to evaluate the lipophilicity of 1.
Park, Sang-Hyun; Choi, Mi-Ran; Park, Jeong-Woong; Park, Ki-Hwan; Chung, Myung-Sub; Ryu, Sangryeol; Kang, Dong-Hyun
2011-08-01
This study was undertaken to investigate the antimicrobial effect of organic acids against Escherichia coli O157:H7, Salmonella Typhimurium, and Listeria monocytogenes on whole red organic apples and lettuce. Several studies have been conducted to evaluate organic acids as sanitizers. However, no studies have compared antimicrobial effects of various organic acids on organic fresh produce, including evaluation of color changes of produce. Apples and lettuce were inoculated with a cocktail of 3 strains each of 3 foodborne pathogens provided above and treated with 1% and 2% organic acids (propionic, acetic, lactic, malic, and citric acid) for 0, 0.5, 1, 5, and 10 min. With increasing treatment time and acid concentration, organic acid treatments showed significant reduction compared to the control treatment (distilled water), and differences in antimicrobial effects between organic acids were observed. After 10 min of treatment with 1% and 2% organic acids in apples, propionic (0.92 to 2.75 log reduction), acetic (0.52 to 2.78 log reduction), lactic (1.69 to >3.42 log reduction), malic (1.48 to >3.42 log reduction), and citric acid (1.52 to >3.42 log reduction) exhibited significant (P < 0.05) antibacterial effects against 3 foodborne pathogens compared to the control treatment. In lettuce, propionic (0.93 to 1.52 log reduction), acetic (1.13 to 1.74 log reduction), lactic (1.87 to 2.54 log reduction), malic (2.32 to 2.98 log reduction), and citric acid (1.85 to 2.86 log reduction) showed significant (P < 0.05) effects compared to the control treatment. Changes in sample color subjected to organic acids treatment were not significant during storage. It is suggested that organic acids have a potential as sanitizers for organic fresh produce. These data may help the organic produce industry provide safe fresh produce for consumers. © 2011 Institute of Food Technologists®
Li, Fei; Su, Qiangfa; Zhou, Zhenming; Liao, Xiaobin; Zou, Jing; Yuan, Baoling; Sun, Wenjie
2018-06-01
The anaerobic biodegradability and metabolic pathways of 8:2 fluorotelomer alcohol (8:2 FTOH) were investigated in anaerobic activated sludge. The biodegradation was well described by a double exponential decay model. 8:2 FTOH was biodegraded to poly- and perfluorinated metabolites with the release of fluoride ion. All polyfluorinated metabolites were intermediate metabolic products and could be further transformed to other metabolites, while perfluorinated metabolites were terminal products. 2H-perfluoro-2-decenoic acid (8:2 FTUA) and perfluorooctanoic acid (PFOA) were verified as the most abundant poly- and perfluorinated metabolites, respectively. Two shorter-chain perfluorinated metabolites, perfluoropentanoic acid (PFPeA) and perfluorobutyric acid (PFBA), were first reported in the biodegradation of 8:2 FTOH. However, the total molar recovery of 8:2 FTOH decreased with increasing incubation time, indicating that there might be some unknown metabolites. Thus, the anaerobic biodegradation pathways were proposed as follows: 8:2 FTOH was oxidized to 8:2 FTUA and 2-perfluorooctyl ethanoic acid (8:2 FTCA) via 2-perfluorooctyl acetaldehyde (8:2 FTAL), and then 8:2 FTUA and 8:2 FTCA were further transformed to 1-perfluoroheptyl ethanol (7:2 sFTOH) via 3-perfluoroheptyl propionic acid (7:3 acid) or/and 3-perfluoroheptyl acrylic acid (7:3 Uacid), and eventually 7:2 sFTOH was further biodegraded to PFOA and other perfluorocarboxylates containing less than eight carbons. Copyright © 2018 Elsevier Ltd. All rights reserved.
Three cocrystals and a cocrystal salt of pyrimidin-2-amine and glutaric acid.
Odiase, Isaac; Nicholson, Catherine E; Ahmad, Ruksanna; Cooper, Jerry; Yufit, Dmitry S; Cooper, Sharon J
2015-04-01
Four new cocrystals of pyrimidin-2-amine and propane-1,3-dicarboxylic (glutaric) acid were crystallized from three different solvents (acetonitrile, methanol and a 50:50 wt% mixture of methanol and chloroform) and their crystal structures determined. Two of the cocrystals, namely pyrimidin-2-amine-glutaric acid (1/1), C4H5N3·C6H8O4, (I) and (II), are polymorphs. The glutaric acid molecule in (I) has a linear conformation, whereas it is twisted in (II). The pyrimidin-2-amine-glutaric acid (2/1) cocrystal, 2C4H5N3·C6H8O4, (III), contains glutaric acid in its linear form. Cocrystal-salt bis(2-aminopyrimidinium) glutarate-glutaric acid (1/2), 2C4H6N3(+)·C6H6O4(2-)·2C6H8O4, (IV), was crystallized from the same solvent as cocrystal (II), supporting the idea of a cocrystal-salt continuum when both the neutral and ionic forms are present in appreciable concentrations in solution. The diversity of the packing motifs in (I)-(IV) is mainly caused by the conformational flexibility of glutaric acid, while the hydrogen-bond patterns show certain similarities in all four structures.
The Effect of Citric Acid on the Oxidation of Organic Contaminants by Fenton's Reagent
NASA Astrophysics Data System (ADS)
Seol, Y.; Javandel, I.; Lee, G.
2003-12-01
Combined with acids and iron catalysts, hydrogen peroxide (H2O2) as Fenton's reagent is proven to be effective in oxidizing halogenated volatile organic compounds (VOCs). The Fenton's reagent, traditionally used for waste water treatment technique, has been applied to the remediation of contaminated soil systems and numerous investigators have found intrinsic iron salts are effective source of iron catalyst for the reaction. Citric acid, which is naturally occurring nutrients to microorganisms and less destructive to soil chemical properties, is selected for an acidifying agent to create acidic soil condition. However, citric acid has been considered as a reaction inhibitant because it sequesters ferric iron from Fenton's catalytic cycle by forming strong chelates with iron. This paper presents the feasibility of using citric acid as an acidifying agent of soil matrix for the Fenton-like oxidation. Series of batch tests were performed to test disappearance of VOCs in various aqueous systems with two acidifying agents (citric acid or sulfuric acid) and three iron sources (iron sulfate, water soluble soil iron, or soil matrix). Batch results show that soluble iron is essential for near complete disappearance of VOCs and that citric acid performs similarly to sulfuric acid at low H2O2 dosage (< 1 wt%). The test soil provided water-soluble soil iron but also contained scavengers of the oxidizing agents, resulting in limited removals of VOCs. Column tests confirmed the results of the batch tests, suggesting citric acid is also as effective as sulfuric acid in providing acidic environment for the Fenton-like oxidation. The batch experiments also reveal that higher doses of H2O2 lower the degree of VOC removals in citric acid systems. Potential explanations for this declining include that excessive presence of H2O2 expedites the oxidation of ferrous to ferric iron, which then forms a strong complex with citrate, leading to the sequestration of the iron from the Fenton's reaction cycle. Consequently, additional supply of ferrous iron would be required for continuing oxidation of VOCs, as well as slow injection of H2O2. Detailed mechanistic study would be needed for factual understanding.
You, Yi-Qian Nancy; Ling, Pei-Ra; Qu, Jason Zhensheng; Bistrian, Bruce R
2008-01-01
Fatty acid absorption patterns can have a major impact on the fatty acid composition in the portal, intestinal lymph, and systemic circulation. This study sought to determine the effects of long-chain triglycerides (LCT), medium-chain triglycerides (MCT), and 2-monododecanoin (2mono) on intestinal fatty acid composition during continuous feeding over a brief period. The lipid sources were 100% LCT, 100% MCT, a 50:50 mixture of LCT and MCT (LCT/MCT), and a 50:50 mixture of LCT and 2mono (LCT/2mono). A total of 27 rats were randomly given 1 of the 4 diets at 200 kcal/kg/d, with 30% of total calories from lipids over 3 hours. MCT significantly increased each of the medium-chain fatty acids (C6:0, C8:0, and C10:0) as free fatty acids in the portal vein and about 10%/mol of C10:0 as triglycerides in the lymph compared with the other groups. There was significantly less C10:0 in lymphatic triglycerides with LCT/MCT than with MCT, but more than in the LCT and LCT/2mono diets. MCT also significantly increased the contents of C16:0, C18:0, C18:1, and C20:4 in the lymphatic triglycerides compared with all other groups including LCT/MCT. The amount of linoleic acid (C18:2) in lymphatic triglycerides followed the relative amounts of this fatty acid in the diet, with the greatest in LCT followed by LCT/MCT and LCT/2mono and least in MCT. A so-called structured lipid composed of the medium-chain fatty acid dodecanoic acid on the 2 position and long-chain fatty acids on the 1 and 3 positions appeared to be endogenously synthesized in response to the LCT/2mono diet. The original differences in MCT and LCT content in the diets were preserved in the fatty acid composition in the intestinal free fatty acids and triglycerides during feeding. In addition, the duration of lipid administration can play a role in altering fatty acid composition in the intestine.
Guerreiro, Joana F.; Muir, Alexander; Ramachandran, Subramaniam; Thorner, Jeremy; Sá-Correia, Isabel
2016-01-01
Acetic acid-induced inhibition of yeast growth and metabolism limits the productivity of industrial fermentation processes, especially when lignocellulosic hydrolysates are used as feedstock in industrial biotechnology. Tolerance to acetic acid of food spoilage yeasts is also a problem in the preservation of acidic foods and beverages. Thus, understanding the molecular mechanisms underlying adaptation and tolerance to acetic acid stress is increasingly important in industrial biotechnology and the food industry. Prior genetic screens for S. cerevisiae mutants with increased sensitivity to acetic acid identified loss-of-function mutations in the YPK1 gene, which encodes a protein kinase activated by the Target of Rapamycin (TOR) Complex 2 (TORC2). We show here by several independent criteria that TORC2-Ypk1 signaling is stimulated in response to acetic acid stress. Moreover, we demonstrate that TORC2-mediated Ypk1 phosphorylation and activation is necessary for acetic acid tolerance, and occurs independently of Hrk1, a protein kinase previously implicated in the cellular response to acetic acid. In addition, we show that TORC2-Ypk1-mediated activation of L-serine: palmitoyl-CoA acyltransferase, the enzyme complex that catalyzes the first committed step of sphingolipid biosynthesis, is required for acetic acid tolerance. Furthermore, analysis of the sphingolipid pathway using inhibitors and mutants indicates that it is production of certain complex sphingolipids that contributes to conferring acetic acid tolerance. Consistent with that conclusion, promoting sphingolipid synthesis by adding exogenous long-chain base precursor phytosphingosine to the growth medium enhanced acetic acid tolerance. Thus, appropriate modulation of the TORC2-Ypk1-sphingolipid axis in industrial yeast strains may have utility in improving fermentations of acetic acid-containing feedstocks. PMID:27671892
[Studies on chemical constituents from herbs of Taraxacum mongolicum].
Shi, Shu-Yun; Zhou, Chang-Xin; Xu, Yan; Tao, Qiao-Feng; Bai, Hua; Lu, Fu-Sheng; Lin, Wen-Yan; Chen, Hai-Yong; Zheng, Wei; Wang, Li-Wei; Wu, Yi-Hang; Zeng, Su; Huang, Ke-Xin; Zhao, Yu; Li, Xiao-Kun; Qu, Jia
2008-05-01
To investigate the chemical constituents of the herbs of Taraxacum mongolicum. The chemical constituents were isolated by various column chromatographic methods and their structures elucidated mainly by NMR and MS evidences. Forty-four components were obtained and identified were as artemetin (1), quercetin (2), quercetin-3', 4', 7-trime-thyl ether (3), luteolin (4), luteolin-7-O-beta-D-glucopyranoside (5), luteolin-7-O-beta-D-galactopyranoside (6), genkwanin (7), isoetin (8), hesperetin (9), genkwanin-4'-O-beta-D-lutinoside (10), hesperidin (11), quercetin-7-O-[beta-D-glucopyranosyl (1-->6) -beta-D-glucopyranoside (12), quercetin-3, 7-O-beta-D-diglucopyranoside (13), isoetin-7-O-beta-D-glucopyranosyl- 2'-O-alpha-L-arabinopyranoside (14), isoetin-7-O-beta-D-glucopyranosyl-2'-O-alpha-D-glucopyranoside (15), isoetin-7- O-beta-D-glucopyranosyl-2'-O-beta-D-xyloypyranoside (16), caffeic acid (17), furulic acid (18), 3-O-caffeoylquinic acid (19), 3, 5-di-O-caffeoylquinic acid (20), 3, 4-di-O-caffeoylquinic acid (21), 4, 5-di-O-caffeoylquinic acid (22), 1-hydroxymethyl-5-hydroxy-phenyl-2-O-beta-D-glucopyranoside (23), p-hydroxybenzoic acid (24), p-coumaric acid (25), 3, 5-dihydroxylbenzoic acid (26), gallic acid (27), gallicin (28), syringic acid (29), 3, 4-dihydroxybenzoic acid (30), caffeic acid ethyl ester (31), esculetin (32), rufescidride (33), mongolicumin A [6, 9, 10-trihydroxy-benzoxanthene-1, 2-dicarboxylic acid] (34), mongolicumin B [1 l-hydroxy-2-oxo-guaia-1 (10), 3, 5-trien-8, 12-lactone] (35), isodonsesquitin A (36), taraxacin (37), sesquiterpene ketolactone (38), taraxasteryl acetate (39), phi-taraxasteryl acetate (40) and lupenol acetate (41), palmitic acid (42), beta-sitosterol (43), and stigmasterol (44). Four compounds (14, 15, 34 and 35) were new compounds, compounds 1, 3, 6-13, 20-22, 30 and 31 were isolated from this genus for the first time, while compounds 18, 23-29, 32 and 37-42 were obtained from this species for the first time.
Properties of Acetate Kinase Isozymes and a Branched-Chain Fatty Acid Kinase from a Spirochete
Harwood, Caroline S.; Canale-Parola, Ercole
1982-01-01
Spirochete MA-2, which is anaerobic, ferments glucose, forming acetate as a major product. The spirochete also ferments (but does not utilize as growth substrates) small amounts of l-leucine, l-isoleucine, and l-valine, forming the branched-chain fatty acids isovalerate, 2-methylbutyrate, and isobutyrate, respectively, as end products. Energy generated through the fermentation of these amino acids is utilized to prolong cell survival under conditions of growth substrate starvation. A branched-chain fatty acid kinase and two acetate kinase isozymes were resolved from spirochete MA-2 cell extracts. Kinase activity was followed by measuring the formation of acyl phosphate from fatty acid and ATP. The branched-chain fatty acid kinase was active with isobutyrate, 2-methylbutyrate, isovalerate, butyrate, valerate, or propionate as a substrate but not with acetate as a substrate. The acetate kinase isozymes were active with acetate and propionate as substrates but not with longer-chain fatty acids as substrates. The acetate kinase isozymes and the branched-chain fatty acid kinase differed in nucleoside triphosphate and cation specificities. Each acetate kinase isozyme had an apparent molecular weight of approximately 125,000, whereas the branched-chain fatty acid kinase had a molecular weight of approximately 76,000. These results show that spirochete MA-2 synthesizes a branched-chain fatty acid kinase specific for leucine, isoleucine, and valine fermentation. It is likely that a phosphate branched-chain amino acids is also synthesized by spirochete MA-2. Thus, in spirochete MA-2, physiological mechanisms have evolved which serve specifically to generate maintenance energy from branched-chain amino acids. PMID:6288660
Synthesis of acetic acid via methanol hydrocarboxylation with CO2 and H2
Qian, Qingli; Zhang, Jingjing; Cui, Meng; Han, Buxing
2016-01-01
Acetic acid is an important bulk chemical that is currently produced via methanol carbonylation using fossil based CO. Synthesis of acetic acid from the renewable and cheap CO2 is of great importance, but state of the art routes encounter difficulties, especially in reaction selectivity and activity. Here we report a route to produce acetic acid from CO2, methanol and H2. The reaction can be efficiently catalysed by Ru–Rh bimetallic catalyst using imidazole as the ligand and LiI as the promoter in 1,3-dimethyl-2-imidazolidinone (DMI) solvent. It is confirmed that methanol is hydrocarboxylated into acetic acid by CO2 and H2, which accounts for the outstanding reaction results. The reaction mechanism is proposed based on the control experiments. The strategy opens a new way for acetic acid production and CO2 transformation, and represents a significant progress in synthetic chemistry. PMID:27165850
Synthesis of acetic acid via methanol hydrocarboxylation with CO2 and H2.
Qian, Qingli; Zhang, Jingjing; Cui, Meng; Han, Buxing
2016-05-11
Acetic acid is an important bulk chemical that is currently produced via methanol carbonylation using fossil based CO. Synthesis of acetic acid from the renewable and cheap CO2 is of great importance, but state of the art routes encounter difficulties, especially in reaction selectivity and activity. Here we report a route to produce acetic acid from CO2, methanol and H2. The reaction can be efficiently catalysed by Ru-Rh bimetallic catalyst using imidazole as the ligand and LiI as the promoter in 1,3-dimethyl-2-imidazolidinone (DMI) solvent. It is confirmed that methanol is hydrocarboxylated into acetic acid by CO2 and H2, which accounts for the outstanding reaction results. The reaction mechanism is proposed based on the control experiments. The strategy opens a new way for acetic acid production and CO2 transformation, and represents a significant progress in synthetic chemistry.
Reactivity of clay minerals with acids and alkalies
Carroll, Dorothy; Starkey, Harry C.
1971-01-01
One-g samples of a montmorillonite, a metabentonite, an illite, two kaolinites, and three halloysites were treated with 50 ml of hydrochloric acid (6⋅45 N, 1:1), acetic acid (4⋅5 N, 1:3), sodium hydroxide (2⋅8 N), sodium chloride solution (pH 6⋅10; Na = 35‰; Cl = 21⋅5‰), and natural sea water (pH 7⋅85; Na = 35⋅5‰; Cl = 21⋅ 5‰) for a 10-day period in stoppered plastic vials. The supernatant solutions were removed from the clay minerals and analyzed for SiO2, Al2O3, CaO, MgO, Na2O, and K2O. All the solutions removed some SiO2, Al2O3, and Fe2O3 from the samples, but the quantities were small. Sodium hydroxide attacked the kaolin group minerals more strongly than it did montmorillonite, metabentonite, or illite. Halloysite was more strongly attacked by hydrochloric acid than was any of the other experimental minerals. Hydrochloric acid removed iron oxide coatings from soil clay minerals, but acetic acid did not remove them completely. The samples most strongly attacked by HCl and NaOH were examined by X-ray diffraction. Acid treatment did not destroy the structure of the clays, but the halloysite structure was partially destroyed. Sodium hydroxide attacked the halloysite structure, as shown by chemical analysis and X-ray diffraction. These experiments show that treatment in dilute acids has no harmful effect in the preparation of clays for X-ray diffraction. Acetic acid is preferred to hydrochloric acid for this purpose. Hydrochloric acid cleans clay minerals by removing free iron oxide from the surface; acetic acid is less effective.
Martin, Gregory G; Atshaves, Barbara P; Landrock, Kerstin K; Landrock, Danilo; Storey, Stephen M; Howles, Philip N; Kier, Ann B; Schroeder, Friedhelm
2014-12-01
On the basis of their abilities to bind bile acids and/or cholesterol, the physiological role(s) of liver fatty acid-binding protein (L-FABP) and sterol carrier protein (SCP) 2/SCP-x (SCP-2/SCP-x) gene products in biliary bile acid and cholesterol formation was examined in gene-ablated male mice. L-FABP (LKO) or L-FABP/SCP-2/SCP-x [triple-knockout (TKO)] ablation markedly decreased hepatic bile acid concentration, while SCP-2/SCP-x [double-knockout (DKO)] ablation alone had no effect. In contrast, LKO increased biliary bile acid, while DKO and TKO had no effect on biliary bile acid levels. LKO and DKO also altered biliary bile acid composition to increase bile acid hydrophobicity. Furthermore, LKO and TKO decreased hepatic uptake and biliary secretion of high-density lipoprotein (HDL)-derived 22-(N-(7-nitrobenz-2-oxa-1,3-diazol-4-yl)amino)-23,24-bisnor-5-cholen-3β-ol (NBD-cholesterol), while DKO alone had no effect. Finally, LKO and, to a lesser extent, DKO decreased most indexes contributing to cholesterol solubility in biliary bile. These results suggest different, but complementary, roles for L-FABP and SCP-2/SCP-x in biliary bile acid and cholesterol formation. L-FABP appears to function more in hepatic retention of bile acids as well as hepatic uptake and biliary secretion of HDL-cholesterol. Conversely, SCP-2/SCP-x may function more in formation and biliary secretion of bile acid, with less impact on hepatic uptake or biliary secretion of HDL-cholesterol. Copyright © 2014 the American Physiological Society.
NASA Astrophysics Data System (ADS)
Roy, Nayan; Paul, Pradip C.; Singh, T. Sanjoy
2015-05-01
Fluorescence properties of Schiff base - N,N‧-bis(salicylidene) - 1,2-phenylenediamine (LH2) is used to study the micelles formed by aggregation of different important bile acids like cholic acid, deoxycholic acid, chenodeoxycholic acid and glycocholic acid by steady state and picosecond time-resolved fluorescence spectroscopy. The fluorescence band intensity was found out to increase with concomitant red shift with gradual addition of different bile acids. Binding constant of the probe with different bile acids as well as critical micelle concentration was obtained from the variation of fluorescence intensity on increasing concentration of bile acids in the medium. The increase in fluorescence quantum yields, fluorescence decay times and substantial decrease in nonradiative decay rate constants in bile acids micellar environment points to the restricted motion of the fluorophore inside the micellar subdomains.
Leenheer, J.A.; Wershaw, R. L.; Reddy, M.M.
1995-01-01
Polycarboxylic acid structures that account for the strong-acid characteristics (pKa1 near 2.0) were examined for fulvic acid from the Suwannee River. Studies of model compounds demonstrated that pKa values near 2.0 occur only if the ??-ether or ??-ester groups were in cyclic structures with two to three additional electronegative functional groups (carboxyl, ester, ketone, aromatic groups) at adjacent positions on the ring. Ester linkage removal by alkaline hydrolysis and destruction of ether linkages through cleavage and reduction with hydriodic acid confirmed that the strong carboxyl acidity in fulvic acid was associated with polycarboxylic ??-ether and ??-ester structures. Studies of hypothetical structural models of fulvic acid indicated possible relation of these polycarboxylic structures with the amphiphilic and metal-binding properties of fulvic acid.
Masi, Marco; Meyer, Susan; Clement, Suzette; Pescitelli, Gennaro; Cimmino, Alessio; Cristofaro, Massimo; Evidente, Antonio
2017-10-27
The fungal pathogen Cochliobolus australiensis isolated from infected leaves of the invasive weed buffelgrass (Pennisetum ciliare) was grown in vitro to evaluate its ability to produce phytotoxic metabolites that could potentially be used as natural herbicides against this weed. Two new tetrasubstituted 3-chromanonacrylic acids, named chloromonilinic acids C (1) and D (2), were isolated from the liquid cultures of C. australiensis, together with the known chloromonilinic acid B. Chloromonilinic acids C and D were characterized by spectroscopic and chemical methods as (E)-3-chloro-3-[(5-hydroxy-3-(1-hydroxy-2-methoxy-2-oxoethyl)-7-methyl-4-oxo-4H-chromen-2-yl)]acrylic acid and (Z)-3-chloro-3-[(5-hydroxy-3-(2-methoxy-2-oxoethyl)-7-methyl-4-oxo-4H-chromen-2-yl)]acrylic acid, respectively. The stereochemistry of chloromonilinic acids C and D was determined using a combination of spectroscopic and computational methods, including electronic circular dichroism. The fungus produced these compounds in two different liquid media together with cochliotoxin, radicinin, radicinol, and their 3-epimers. The radicinin-related compounds were also produced when the fungus was grown in wheat seed solid culture, but chloromonilinic acids were not found in the solid culture organic extract. All three chloromonilinic acids were toxic to buffelgrass in a seedling elongation bioassay, with significantly delayed germination and dramatically reduced radicle growth, especially at a concentration of 5 × 10 -3 M.
Carretta, M D; Hidalgo, A I; Burgos, J; Opazo, L; Castro, L; Hidalgo, M A; Figueroa, C D; Taubert, A; Hermosilla, C; Burgos, R A
2016-08-01
Increased short-chain fatty acid (SCFA) production is associated with subacute ruminal acidosis (SARA) and activation of inflammatory processes. In humans and rodents, SCFAs modulate inflammatory responses in the gut via free fatty acid receptor 2 (FFA2). In bovines, butyric acid is one of the most potent FFA2 agonists. Its expression in bovine neutrophils has recently been demonstrated, suggesting a role in innate immune response in cattle. This study aimed to evaluate if butyric acid modulates oxidative and non-oxidative functions or if it can potentiate other inflammatory mediators in bovine neutrophils. Our results showed that butyric acid can activate bovine neutrophils, inducing calcium (Ca(2+)) influx and mitogen-activated protein kinase (MAPK) phosphorylation, two second messengers involved in FFA2 activation. Ca(2+) influx induced by butyric acid was dependent on the extracellular and intracellular Ca(2+) source and phospholipase C (PLC) activation. Butyric acid alone had no significant effect on reactive oxygen species (ROS) production and chemotaxis; however, a priming effect on platelet-activating factor (PAF), a potent inflammatory mediator, was observed. Butyric acid increased CD63 expression and induced the release of neutrophil granule markers matrix metalloproteinase-9 (MMP-9) and lactoferrin. Finally, we observed that butyric acid induced neutrophil extracellular trap (NET) formation without affecting cellular viability. These findings suggest that butyric acid, a component of the ruminal fermentative process, can modulate the innate immune response of ruminants. Copyright © 2016 Elsevier B.V. All rights reserved.
Growth of nitric acid hydrates on thin sulfuric acid films
NASA Technical Reports Server (NTRS)
Iraci, Laura T.; Middlebrook, Ann M.; Wilson, Margaret A.; Tolbert, Margaret A.
1994-01-01
Type I polar stratospheric clouds (PSCs) are thought to nucleate and grow on stratospheric sulfate aerosols (SSAs). To model this system, thin sulfuric acid films were exposed to water and nitric acid vapors (1-3 x 10(exp -4) Torr H2O and 1-2.5 x 10(exp -6) Torr HNO3) and subjected to cooling and heating cycles. Fourier Transform Infrared (FTIR) spectroscopy was used to probe the phase of the sulfuric acid and to identify the HNO3/H2O films that condensed. Nitric acid trihydrate (NAT) was observed to grow on crystalline sulfuric acid tetrahydrate (SAT) films. NAT also condensed in/on supercooled H2SO4 films without causing crystallization of the sulfuric acid. This growth is consistent with NAT nucleation from ternary solutions as the first step in PSC formation.
Fan, Sufang; Wang, Xiupin; Li, Peiwu; Zhang, Qi; Zhang, Wen
2011-03-01
In the experiment, a high-performance liquid chromatography and electrospray ionization-tandem mass spectrometry with selected reaction monitoring was used to simultaneously determine various classes of phytohormones, including indole-3-acetic acid, α-naphthaleneacetic acid, 2-chlorobenzoic acid, 4-chlorobenzoic acid, indole-3-butyric acid, gibberellic acid, 2,4-dichlorophenoxyacetic acid, 2-naphthoxyacetic acid, abscisic acid, 2,3,5-triiodobenzoic acid, uniconazole, paclobutrazol and 2,4-epibassinolide in rape tissues. The analyses were separated by an HPLC equipped with a reversed-phase column using a binary solvent system composed of methanol and water, both containing 0.1% of formic acid. The matrix effect was also considered and determined. The technology was applied to analyze rape tissues, including roots, stems, leaves, flowers, immature pods and rape seeds. The rape tissues were subjected to ultrasound-assisted extraction and purified by dispersive solid-phase extraction, and then transferred into the liquid chromatography system. The detection limit for each plant hormone was defined by the ratio of signal/background noise (S/N) of 3. The results showed perfect linearity (R(2) values of 0.9987-1.0000) and reproducibility of elution times (relative standard deviations, RSDs,<1%) and peak areas (RSDs,<7%) for all target compounds. Copyright © 2011 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.
Qiu, Shiran; Gözdereliler, Erkin; Weyrauch, Philip; Lopez, Eva C Magana; Kohler, Hans-Peter E; Sørensen, Sebastian R; Meckenstock, Rainer U; Elsner, Martin
2014-05-20
Phenoxy acid herbicides are important groundwater contaminants. Stable isotope analysis and enantiomer analysis are well-recognized approaches for assessing in situ biodegradation in the field. In an aerobic degradation survey with six phenoxyacetic acid and three phenoxypropionic acid-degrading bacteria we measured (a) enantiomer-specific carbon isotope fractionation of MCPP ((R,S)-2-(4-chloro-2-methylphenoxy)-propionic acid), DCPP ((R,S)-2-(2,4-dichlorophenoxy)-propionic acid), and 4-CPP ((R,S)-2-(4-chlorophenoxy)-propionic acid); (b) compound-specific isotope fractionation of MCPA (4-chloro-2-methylphenoxyacetic acid) and 2,4-D (2,4-dichlorophenoxyacetic acid); and (c) enantiomer fractionation of MCPP, DCPP, and 4-CPP. Insignificant or very slight (ε = -1.3‰ to -2.0‰) carbon isotope fractionation was observed. Equally small values in an RdpA enzyme assay (εea = -1.0 ± 0.1‰) and even smaller fractionation in whole cell experiments of the host organism Sphingobium herbicidovorans MH (εwc = -0.3 ± 0.1‰) suggest that (i) enzyme-associated isotope effects were already small, yet (ii) further masked by active transport through the cell membrane. In contrast, enantiomer fractionation in MCPP, DCPP, and 4-CPP was pronounced, with enantioselectivities (ES) of -0.65 to -0.98 with Sphingomonas sp. PM2, -0.63 to -0.89 with Sphingobium herbicidovorans MH, and 0.74 to 0.97 with Delftia acidovorans MC1. To detect aerobic biodegradation of phenoxypropionic acids in the field, enantiomer fractionation seems, therefore, a stronger indicator than carbon isotope fractionation.
Ervin, Kent M; Nickel, Alex A; Lanorio, Jerry G; Ghale, Surja B
2015-07-16
A meta-analysis of experimental information from a variety of sources is combined with statistical thermodynamics calculations to refine the gas-phase acidity scale from hydrogen sulfide to pyrrole. The absolute acidities of hydrogen sulfide, methanethiol, and pyrrole are evaluated from literature R-H bond energies and radical electron affinities to anchor the scale. Relative acidities from proton-transfer equilibrium experiments are used in a local thermochemical network optimized by least-squares analysis to obtain absolute acidities of 14 additional acids in the region. Thermal enthalpy and entropy corrections are applied using molecular parameters from density functional theory, with explicit calculation of hindered rotor energy levels for torsional modes. The analysis reduces the uncertainties of the absolute acidities of the 14 acids to within ±1.2 to ±3.3 kJ/mol, expressed as estimates of the 95% confidence level. The experimental gas-phase acidities are compared with calculations, with generally good agreement. For nitromethane, ethanethiol, and cyclopentadiene, the refined acidities can be combined with electron affinities of the corresponding radicals from photoelectron spectroscopy to obtain improved values of the C-H or S-H bond dissociation energies, yielding D298(H-CH2NO2) = 423.5 ± 2.2 kJ mol(-1), D298(C2H5S-H) = 364.7 ± 2.2 kJ mol(-1), and D298(C5H5-H) = 347.4 ± 2.2 kJ mol(-1). These values represent the best-available experimental bond dissociation energies for these species.
2005-01-01
The recent discovery that the natriuretic peptide OvCNPb (Ornithorhynchus venom C-type natriuretic peptide B) from platypus (Ornithorynchus anatinus) venom contains a D-amino acid residue suggested that other D-amino-acid-containing peptides might be present in the venom. In the present study, we show that DLP-2 (defensin-like peptide-2), a 42-amino-acid residue polypeptide in the platypus venom, also contains a D-amino acid residue, D-methionine, at position 2, while DLP-4, which has an identical amino acid sequence, has all amino acids in the L-form. These findings were supported further by the detection of isomerase activity in the platypus gland venom extract that converts DLP-4 into DLP-2. In the light of this new information, the tertiary structure of DLP-2 was recalculated using a new structural template with D-Met2. The structure of DLP-4 was also determined in order to evaluate the effect of a D-amino acid at position 2 on the structure and possibly to explain the large retention time difference observed for the two molecules in reverse-phase HPLC. The solution structures of the DLP-2 and DLP-4 are very similar to each other and to the earlier reported structure of DLP-2, which assumed that all amino acids were in the L-form. Our results suggest that the incorporation of the D-amino acid at position 2 has minimal effect on the overall fold in solution. PMID:16033333
Wu, Huibin; Song, Zhengguo; Wang, Xiao; Liu, Zhongqi; Tang, Shirong
2016-09-01
Environmental pollution by both ambient CO2 and heavy metals has been steadily increasing, but we do not know how fluctuating CO2 concentrations influence plant nutrients under high Cd pollution, especially in crops. Here, we studied the effects of elevated CO2 and Cd accumulation on proteins and amino acids in rice under Cd stress. In this pot experiment, we analyzed the amino-acid profile of 20 rice cultivars that accumulate Cd differently; the plants were grown in Cd-containing soils under ambient conditions and elevated CO2 levels. We found that although Cd concentrations appeared to be higher in most cultivars under elevated CO2 than under ambient CO2, the effect was significant only in seven cultivars. Combined exposure to Cd and elevated CO2 strongly decreased rice protein and amino acid profiles, including essential and non-essential amino acids. Under elevated CO2, the ratios of specific amino acids were either higher or lower than the optimal ratios provided by FAO/WHO, suggesting that CO2 may flatten the overall amino-acid profile, leading to an excess in some amino acids and deficiencies in others when the rice is consumed. Thus, Cd-tainted rice limits the concentration of essential amino acids in rice-based diets, and the combination with elevated CO2 further exacerbates the problem. Copyright © 2016 Elsevier Ltd. All rights reserved.
Influence of Fluorine Atoms and Aromatic Rings on the Acidity of Ethanol
NASA Astrophysics Data System (ADS)
Ramírez, Ramsés E.; García-Martínez, Cirilo; Méndez, Francisco
2009-09-01
Absolute gas-phase acidities ΔacidG0(OH) and ΔacidG0(CH) were calculated at the B3LYP and MP2 levels using six different standard basis sets for the OH and CH heterolytic bond cleavage of ethanol and twelve derivatives of the type CH3-nFnCHXrOH, where n ranges from zero to three and represents the number of fluorine atoms and r represents hydrogen and the type of aromatic ring, namely: X0 = hydrogen, X1 = phenyl, X2 = 1-naphthyl, and X3 = 9-anthryl. The similarity between calculated and experimental ΔacidG0(OH) values for ethanol (1a), 2-fluoroethanol (1b), 2,2-difluoroethanol (1c), 2,2,2-trifluoroethanol (1d), and 1-phenylethanol (2a) was used to validate the right theoretical method for this study. Substituent partial contributions to hydroxyl-, methylene-, and methine-hydrogen acidities were evaluated by linear combination. Good parameter fittings of the primary and secondary alcohols were obtained and interpreted as additive contribution of the substituent effects. The nonlinear contributions were identified. Calculations prove that fluoroalcohols exhibit C-H acidity, which is usually lower than O-H acidity. In principle, the inversion of this acidity order is possible by the introduction of a large aromatic ring instead to increase the number of fluorine atoms.
Athukuri, Bhargavi Latha; Neerati, Prasad
2016-12-01
Cytochrome P450-2D6 (CYP2D6), a member of the CYP450 mixed function oxidase system, is an important CYP isoform with regard to herbal-drug interactions and is responsible for the metabolism of nearly 25% of drugs. Until now, studies on the effects of various phytochemicals on CYP2D6 activity in vivo have been very rare. Gallic acid and ellagic acid are natural polyphenols which are widely distributed in fruits and medicinal plants. In the present study, the effects of gallic acid and ellagic acid pretreatment on intestinal transport and oral bioavailability of metoprolol were investigated. The intestinal transport of metoprolol was assessed by conducting an in situ single pass intestinal perfusion (SPIP) study. The bioavailability study was conducted to evaluate the pharmacokinetic parameters of orally administered metoprolol in rats. After pretreatment with gallic acid and ellagic acid, no significant change in effective permeability of metoprolol was observed at the ileum part of rat intestine. A significant improvement in the peak plasma concentration (Cmax) and area under the serum concentration-time profile (AUC) and decrease in clearance were observed in rats pretreated with gallic acid and ellagic acid. Gallic acid and ellagic acid significantly enhanced the oral bioavailability of metoprolol by inhibiting CYP2D6-mediated metabolism in the rat liver. Hence, adverse herbal-drug interactions may result with concomitant ingestion of gallic acid and ellagic acid supplements and drugs that are CYP2D6 substrates. The clinical assessment of these interactions should be further investigated in human volunteers.
Tyrosol and its analogues inhibit alpha-melanocyte-stimulating hormone induced melanogenesis.
Wen, Kuo-Ching; Chang, Chih-Shiang; Chien, Yin-Chih; Wang, Hsiao-Wen; Wu, Wan-Chen; Wu, Chin-Sheng; Chiang, Hsiu-Mei
2013-11-28
Melanin is responsible for skin color and plays a major role in defending against harmful external factors such as ultraviolet (UV) irradiation. Tyrosinase is responsible for the critical steps of melanogenesis, including the rate-limiting step of tyrosine hydroxylation. The mechanisms of action of skin hypopigmenting agents are thought to be based on the ability of a given agent to inhibit the activity of tyrosinase and, hence, down regulate melanin synthesis. Tyrosol and its glycoside, salidroside, are active components of Rhodiola rosea, and in our preliminary study we found that Rhodiola rosea extract inhibited melanogenesis. In this study, we examined the effects of tyrosol and its analogues on melanin synthesis. We found that treatment of B16F0 cells to tyrosol (1), 4-hydroxyphenylacetic acid (5), 3-hydroxyphenylacetic acid (6), 2-hydroxyphenylacetic acid (7), or salidroside (11) resulted in a reduction in melanin content and inhibition of tyrosinase activity as well as its expression. Tyrosol (1), 4-hydroxyphenylacetic acid (5) and 2-hydroxyphenylacetic acid (7) suppressed MC1R expression. Tyrosol (1), 4-hydroxyphenylacetic acid (5), 3-hydroxyphenylacetic acid (6), and 2-hydroxyphenylacetic acid (7) inhibited α-MSH induced TRP-1 expression, but salidroside (11) did not. All the compounds did not affect MITF and TRP-2 expression. Furthermore, we found that the cell viability of tyrosol (1), 4-hydroxyphenylacetic acid (5), 3-hydroxyphenylacetic acid (6), and 2-hydroxyphenylacetic acid (7) at concentrations below 4 mM and salidroside (11) at concentrations below 0.5 mM were higher than 90%. The compounds exhibited metal-coordinating interactions with copper ion in molecular docking with tyrosinase. Our results suggest that tyrosol, 4-hydroxyphenylacetic acid, 3-hydroxyphenylacetic acid, 2-hydroxyphenylacetic acid, and salidroside are potential hypopigmenting agents.
Tyrosol and Its Analogues Inhibit Alpha-Melanocyte-Stimulating Hormone Induced Melanogenesis
Wen, Kuo-Ching; Chang, Chih-Shiang; Chien, Yin-Chih; Wang, Hsiao-Wen; Wu, Wan-Chen; Wu, Chin-Sheng; Chiang, Hsiu-Mei
2013-01-01
Melanin is responsible for skin color and plays a major role in defending against harmful external factors such as ultraviolet (UV) irradiation. Tyrosinase is responsible for the critical steps of melanogenesis, including the rate-limiting step of tyrosine hydroxylation. The mechanisms of action of skin hypopigmenting agents are thought to be based on the ability of a given agent to inhibit the activity of tyrosinase and, hence, down regulate melanin synthesis. Tyrosol and its glycoside, salidroside, are active components of Rhodiola rosea, and in our preliminary study we found that Rhodiola rosea extract inhibited melanogenesis. In this study, we examined the effects of tyrosol and its analogues on melanin synthesis. We found that treatment of B16F0 cells to tyrosol (1), 4-hydroxyphenylacetic acid (5), 3-hydroxyphenylacetic acid (6), 2-hydroxyphenylacetic acid (7), or salidroside (11) resulted in a reduction in melanin content and inhibition of tyrosinase activity as well as its expression. Tyrosol (1), 4-hydroxyphenylacetic acid (5) and 2-hydroxyphenylacetic acid (7) suppressed MC1R expression. Tyrosol (1), 4-hydroxyphenylacetic acid (5), 3-hydroxyphenylacetic acid (6), and 2-hydroxyphenylacetic acid (7) inhibited α-MSH induced TRP-1 expression, but salidroside (11) did not. All the compounds did not affect MITF and TRP-2 expression. Furthermore, we found that the cell viability of tyrosol (1), 4-hydroxyphenylacetic acid (5), 3-hydroxyphenylacetic acid (6), and 2-hydroxyphenylacetic acid (7) at concentrations below 4 mM and salidroside (11) at concentrations below 0.5 mM were higher than 90%. The compounds exhibited metal-coordinating interactions with copper ion in molecular docking with tyrosinase. Our results suggest that tyrosol, 4-hydroxyphenylacetic acid, 3-hydroxyphenylacetic acid, 2-hydroxyphenylacetic acid, and salidroside are potential hypopigmenting agents. PMID:24287915
Wu, Jason H Y; Marklund, Matti; Imamura, Fumiaki; Tintle, Nathan; Ardisson Korat, Andres V; de Goede, Janette; Zhou, Xia; Yang, Wei-Sin; de Oliveira Otto, Marcia C; Kröger, Janine; Qureshi, Waqas; Virtanen, Jyrki K; Bassett, Julie K; Frazier-Wood, Alexis C; Lankinen, Maria; Murphy, Rachel A; Rajaobelina, Kalina; Del Gobbo, Liana C; Forouhi, Nita G; Luben, Robert; Khaw, Kay-Tee; Wareham, Nick; Kalsbeek, Anya; Veenstra, Jenna; Luo, Juhua; Hu, Frank B; Lin, Hung-Ju; Siscovick, David S; Boeing, Heiner; Chen, Tzu-An; Steffen, Brian; Steffen, Lyn M; Hodge, Allison; Eriksdottir, Gudny; Smith, Albert V; Gudnason, Vilmunder; Harris, Tamara B; Brouwer, Ingeborg A; Berr, Claudine; Helmer, Catherine; Samieri, Cecilia; Laakso, Markku; Tsai, Michael Y; Giles, Graham G; Nurmi, Tarja; Wagenknecht, Lynne; Schulze, Matthias B; Lemaitre, Rozenn N; Chien, Kuo-Liong; Soedamah-Muthu, Sabita S; Geleijnse, Johanna M; Sun, Qi; Harris, William S; Lind, Lars; Ärnlöv, Johan; Riserus, Ulf; Micha, Renata; Mozaffarian, Dariush
2017-12-01
The metabolic effects of omega-6 polyunsaturated fatty acids (PUFAs) remain contentious, and little evidence is available regarding their potential role in primary prevention of type 2 diabetes. We aimed to assess the associations of linoleic acid and arachidonic acid biomarkers with incident type 2 diabetes. We did a pooled analysis of new, harmonised, individual-level analyses for the biomarkers linoleic acid and its metabolite arachidonic acid and incident type 2 diabetes. We analysed data from 20 prospective cohort studies from ten countries (Iceland, the Netherlands, the USA, Taiwan, the UK, Germany, Finland, Australia, Sweden, and France), with biomarkers sampled between 1970 and 2010. Participants included in the analyses were aged 18 years or older and had data available for linoleic acid and arachidonic acid biomarkers at baseline. We excluded participants with type 2 diabetes at baseline. The main outcome was the association between omega-6 PUFA biomarkers and incident type 2 diabetes. We assessed the relative risk of type 2 diabetes prospectively for each cohort and lipid compartment separately using a prespecified analytic plan for exposures, covariates, effect modifiers, and analysis, and the findings were then pooled using inverse-variance weighted meta-analysis. Participants were 39 740 adults, aged (range of cohort means) 49-76 years with a BMI (range of cohort means) of 23·3-28·4 kg/m 2 , who did not have type 2 diabetes at baseline. During a follow-up of 366 073 person-years, we identified 4347 cases of incident type 2 diabetes. In multivariable-adjusted pooled analyses, higher proportions of linoleic acid biomarkers as percentages of total fatty acid were associated with a lower risk of type 2 diabetes overall (risk ratio [RR] per interquintile range 0·65, 95% CI 0·60-0·72, p<0·0001; I 2 =53·9%, p heterogeneity =0·002). The associations between linoleic acid biomarkers and type 2 diabetes were generally similar in different lipid compartments, including phospholipids, plasma, cholesterol esters, and adipose tissue. Levels of arachidonic acid biomarker were not significantly associated with type 2 diabetes risk overall (RR per interquintile range 0·96, 95% CI 0·88-1·05; p=0·38; I 2 =63·0%, p heterogeneity <0·0001). The associations between linoleic acid and arachidonic acid biomarkers and the risk of type 2 diabetes were not significantly modified by any prespecified potential sources of heterogeneity (ie, age, BMI, sex, race, aspirin use, omega-3 PUFA levels, or variants of the FADS gene; all p heterogeneity ≥0·13). Findings suggest that linoleic acid has long-term benefits for the prevention of type 2 diabetes and that arachidonic acid is not harmful. Funders are shown in the appendix. Copyright © 2017 Elsevier Ltd. All rights reserved.
Mavraganis, Ioannis; Meesapyodsuk, Dauenpen; Vrinten, Patricia; Smith, Mark; Qiu, Xiao
2010-02-01
Claviceps purpurea, the fungal pathogen that causes the cereal disease ergot, produces glycerides that contain high levels of ricinoleic acid [(R)-12-hydroxyoctadec-cis-9-enoic acid] in its sclerotia. Recently, a fatty acid hydroxylase (C. purpurea FAH [CpFAH]) involved in the biosynthesis of ricinoleic acid was identified from this fungus (D. Meesapyodsuk and X. Qiu, Plant Physiol. 147:1325-1333, 2008). Here, we describe the cloning and biochemical characterization of a C. purpurea type II diacylglycerol acyltransferase (CpDGAT2) involved in the assembly of ricinoleic acid into triglycerides. The CpDGAT2 gene was cloned by degenerate RT-PCR (reverse transcription-PCR). The expression of this gene restored the in vivo synthesis of triacylglycerol (TAG) in the quadruple mutant strain Saccharomyces cerevisiae H1246, in which all four TAG biosynthesis genes (DGA1, LRO1, ARE1, and ARE2) are disrupted. In vitro enzymatic assays using microsomal preparations from the transformed yeast strain indicated that CpDGAT2 prefers ricinoleic acid as an acyl donor over linoleic acid, oleic acid, or linolenic acid, and it prefers 1,2-dioleoyl-sn-glycerol over 1,2-dipalmitoyl-sn-glycerol as an acyl acceptor. The coexpression of CpFAH with CpDGAT2 in yeast resulted in an increased accumulation of ricinoleic acid compared to the coexpression of CpFAH with the native yeast DGAT2 (S. cerevisiae DGA1 [ScDGA1]) or the expression of CpFAH alone. Northern blot analysis indicated that CpFAH is expressed solely in sclerotium cells, with no transcripts of this gene being detected in mycelium or conidial cells. CpDGAT2 was more widely expressed among the cell types examined, although expression was low in conidiospores. The high expression of CpDGAT2 and CpFAH in sclerotium cells, where high levels of ricinoleate glycerides accumulate, provided further evidence supporting the roles of CpDGAT2 and CpFAH as key enzymes for the synthesis and assembly of ricinoleic acid in C. purpurea.
USDA-ARS?s Scientific Manuscript database
Commercial peracetic acid (PAA) formulations are acidic mixtures of PAA, hydrogen peroxide (H2O2), acetic acid (AA), H2O and stabilizers to maintain equilibrium of the concentrations. Different PAA formulations show diverse PAA/H2O2 ratios, leading to potentially different toxicities at the same con...
Mohamed, Maged E; Pahirulzaman, Khomaizon A K; Lazarus, Colin M
2016-03-01
Pyrethrins are natural insecticides, which accumulate to high concentrations in pyrethrum (Chrysanthemum cinerariaefolium) flowers. Synthetic pyrethroids are more stable, more efficacious and cheaper, but contemporary requirements for safe and environmentally friendly pesticides encourage a return to the use of natural pyrethrins, and this would be favoured by development of an efficient route to their production by microbial fermentation. The biosynthesis of pyrethrins involves ester linkage between an acid moiety (chrysanthemoyl or pyrethroyl, synthesised via the mevalonic acid pathway from glucose), and an alcohol (pyrethrolone). Pyrethrolone is generated from 3-oxo-2-(2'-pentenyl)-cyclopentane-1-octanoic acid, which originates from α-linolenic acid via the jasmonic acid biosynthetic cascade. The first four genes in this cascade, encoding lipoxygenase 2, allene-oxide synthase, allene-oxide cyclase 2 and 12-oxophytodienoic acid reductase 3, were amplified from an Arabidopsis thaliana cDNA library, cloned in a purpose-built fungal multigene expression vector and expressed in Aspergillus oryzae. HPLC-MS analysis of the transgenic fungus homogenate gave good evidence for the presence of 3-oxo-2-(2'-pentenyl)-cyclopentane-1-octanoic acid.
Biological Activities of Oleanolic Acid Derivatives from Calendula officinalis Seeds.
Zaki, Ahmed; Ashour, Ahmed; Mira, Amira; Kishikawa, Asuka; Nakagawa, Toshinori; Zhu, Qinchang; Shimizu, Kuniyoshi
2016-05-01
Phytochemical examination of butanol fraction of Calendula officinalis seeds led to the isolation of two compounds identified as 28-O-β-D-glucopyranosyl-oleanolic acid 3-O-β-D-glucopyranosyl (1→3)-β-D-glucopyranosiduronic acid (CS1) and oleanolic acid 3-O-β-D-glucopyranosyl (1→3)-β-D-glucopyranosiduronic acid (CS2). Biological evaluation was carried out for these two compounds such as melanin biosynthesis inhibitory, hyaluronic acid production activities, anti obesity using lipase inhibition and adipocyte differentiation as well as evaluation of the protective effect against hydrogen peroxide induced neurotoxicity in neuro-2A cells. The results showed that, compound CS2 has a melanin biosynthesis stimulatory activity; however, compound CS1 has a potent stimulatory effect for the production of hyaluronic acid on normal human dermal fibroblast from adult (NHDF-Ad). Both compounds did not show any inhibitory effect on both lipase and adipocyte differentiation. Compound CS2 could protect neuro-2A cells and increased cell viability against H2 O2 . These activities (melanin biosynthesis stimulatory and protective effect against H2 O2 of CS2 and hyaluronic acid productive activities of these triterpene derivatives) have been reported for the first time. Copyright © 2016 John Wiley & Sons, Ltd. Copyright © 2016 John Wiley & Sons, Ltd.
Feung, Chao-Shieung; Hamilton, Robert H.; Witham, Francis H.; Mumma, Ralph O.
1972-01-01
Soybean (Glycine max L.) cotyledon callus grown on radioactive 2,4-dichlorophenoxyacetic acid (2,4-D-1-14C) as an auxin produced 2,4-D metabolites, which qualitatively and quantitatively changed with time. Water soluble fractions from the tissue exhibited a steady increase in radioactivity during the course of 24 days. Following β-glucosidase treatment, at least eight aglycones were obtained from the water soluble fraction of the tissue after 8 days. The metabolite, 4-hydroxy-2,5-dichlorophenoxyacetic acid was the most abundant aglycone during the entire 32 day growth period while 4-hydroxy-2,3-dichlorophenoxyacetic acid was detected as a minor metabolite. Radioactivity in the ether soluble acidic fractions reached a maximum of 82% of the total in the tissue after 2 days. The level then decreased to 44% by the end of 24 days. A total of seven ether soluble components were detected. In addition to 2,4-D glutamic acid, which was detected in high amounts after 24 hours, 2,4-D aspartic acid was found to be the most abundant ether soluble metabolite after longer time periods. Mass spectral data and a fragmentation pattern are presented for 2,4-D aspartic acid. PMID:16658138
NASA Astrophysics Data System (ADS)
Shimonishi, Y.; Zhang, T.; Johnson, P.; Imanishi, N.; Hirano, A.; Takeda, Y.; Yamamoto, O.; Sammes, N.
The stability of a NASICON-type lithium ion conducting solid electrolyte, Li 1+ x+ yTi 2- xAl xP 3- ySi yO 12 (LTAP), in acetic acid and formic acid solutions was examined. XRD patterns of the LTAP powders immersed in 100% acetic acid and formic acid at 50 °C for 4 months showed no change as compared to the pristine LTAP. However, the electrical conductivity of LTAP drastically decreased. On the other hand, no significant electrical conductivity change of LTAP immersed in lithium formate saturated formic acid-water solution was observed, and the electrical conductivity of LTAP immersed in lithium acetate saturated acetic acid-water increased. Cyclic voltammogram tests suggested that acetic acid was stable up to a high potential, but formic acid decomposed under the decomposition potential of water. The acetic acid solution was considered to be a candidate for the active material in the air electrode of lithium-air rechargeable batteries. The cell reaction was considered as 2Li + 2 CH 3COOH + 1/2O 2 = 2CH 3COOLi + H 2O. The energy density of this lithium-air system is calculated to be 1477 Wh kg -1 from the weights of Li and CH 3COOH, and an observed open-circuit voltage of 3.69 V.
Regulation of palmitoyl-CoA chain elongation by clofibric acid in the liver of Zucker fa/fa rats.
Toyama, Tomoaki; Kudo, Naomi; Mitsumoto, Atsushi; Kawashima, Yoichi
2005-05-01
The regulation of palmitoyl-CoA chain elongation (PCE) by clofibric acid [2-(4-chlorophenoxy)-2-methylpropionic acid] was investigated in comparison with stearoyl-CoA desaturase (SCD) in the liver of obese Zucker fa/fa rats. The proportion of oleic acid in the hepatic lipids of Zucker obese rats is 2.7 times higher than that of lean littermates. The activities of PCE and SCD in the liver of Zucker obese rats were markedly higher than in lean rats, and the hepatic uptake of 2-deoxyglucose (2-DG) was also higher in Zucker obese rats compared with lean rats. The increased activities of SCD and PCE in Zucker obese rats were due to the enhanced expression of mRNA of both SCD1 and rat FA elongase 2 (rELO2), but not SCD2 or rELO1. The proportion of oleic acid in the liver was significantly increased by the administration of clofibric acid to Zucker obese rats, and the hepatic PCE activity and rELO2 mRNA expression, but not the SCD activity or SCD1 mRNA expression, were increased in response to clofibric acid treatment. By contrast, the activities of both PCE and SCD and the mRNA expression of SCD1 and rELO2 in the liver were increased by the treatment of Zucker lean rats with clofibric acid. Multiple regression analysis, which was performed to determine the relationships involving PCE activity, SCD activity, and the proportion of oleic acid, revealed that the three parameters were significantly correlated and that the standardized partial regression coefficient of PCE was higher than that of SCD. These results indicate that oleic acid is synthesized by the concerted action of PCE and SCD and that PCE plays a crucial role in the formation of oleic acid when Zucker fa/fa rats are given clofibric acid.
Mori, Masanobu; Tanaka, Kazuhiko; Satori, Tatsuya; Ikedo, Mikaru; Hu, Wenzhi; Itabashi, Hideyuki
2006-06-16
Influence of acidic eluent on retention behaviors of common anions and cations by ion-exclusion/cation-exchange chromatography (ion-exclusion/CEC) were investigated on a weakly acidic cation-exchange resin in the H(+)-form with conductivity. Sensitivities of analyte ions, especially weak acid anions (F(-) and HCOO(-)), were affected with degree of background conductivity level with pK(a1) (first dissociation constant) of acid in eluent. The retention behaviors of anions and cations were related to that of elution dip induced after eluting acid to separation column and injecting analyte sample. These results were largely dependent on the natures of acid as eluent. Through this study, succinic acid as the eluent was suitable for simultaneous separation of strong acid anions (SO(4)(2-), Cl(-), NO(3)(-) and I(-)), weak acid anions (F(-), HCOO(-) and CH(3)COO(-)), and cations (Na(+), K(+), NH(4)(+), Mg(2+) and Ca(2+)). The separation was achieved in 20 min under the optimum eluent condition, 20 mM succinic acid/2 mM 18-crown-6. Detection limits at S/N=3 ranged from 0.10 to 0.51 microM for strong acid anions, 0.20 to 5.04 microM for weak acid anions and 0.75 to 1.72 microM for cations. The relative standard deviations of peak areas in the repeated chromatographic runs (n=10) were in the range of 1.1-2.9% for anions and 1.8-4.5% for cations. This method was successfully applied to hot spring water containing strong acid anions, weak acid anions and cations, with satisfactory results.
Transepithelial transport of alpha-lipoic acid across human intestinal Caco-2 cell monolayers.
Takaishi, Naoki; Yoshida, Kazutaka; Satsu, Hideo; Shimizu, Makoto
2007-06-27
Alpha-lipoic acid (LA) is used in dietary supplements or food with antioxidative functions. The mechanism for the intestinal absorption of alpha-lipoic acid was investigated in this study by using human intestinal Caco-2 cell monolayers. LA was rapidly transported across the Caco-2 cell monolayers, this transport being energy-dependent, suggesting transporter-mediated transport to be the mechanism involved. The LA transport was strongly dependent on the pH value, being accelerated in the acidic pH range. Furthermore, such monocarboxylic acids as benzoic acid and medium-chain fatty acids significantly inhibited LA transport, suggesting that a proton-linked monocarboxylic acid transporter (MCT) was involved in the intestinal transport of LA. The conversion of LA to the more antioxidative dihydrolipoic acid was also apparent during the transport process.
Kobayashi, Misato; Hoshinaga, Yukiko; Miura, Natsuko; Tokuda, Yuki; Shigeoka, Shigeru; Murai, Atsushi; Horio, Fumihiko
2014-01-01
The mechanisms underlying the decrease in hepatic cytochrome P-450 (CYP) content in ascorbic acid deficiency was investigated in scurvy-prone ODS rats. First, male ODS rats were fed a diet containing sufficient ascorbic acid (control) or a diet without ascorbic acid (deficient) for 18 days, with or without the intraperitoneal injection of phenobarbital. Ascorbic acid deficiency decreased hepatic microsomal total CYP content, CYP2B1/2B2 protein, and mitochondrial cytochrome oxidase (COX) complex IV subunit I protein, and simultaneously increased heme oxygenase-1 protein in microsomes and mitochondria. Next, heme oxygenase-1 inducers, that is lipopolysaccharide and hemin, were administered to phenobaribital-treated ODS rats fed sufficient ascorbic acid. The administration of these inducers decreased hepatic microsomal total CYP content, CYP2B1/2B2 protein, and mitochondrial COX complex IV subunit I protein. These results suggested that the stimulation of hepatic heme oxygenase-1 expression by ascorbic acid deficiency caused the decrease in CYP content in liver.
Rode, Ulrike; Müller, Rudolf
1998-01-01
Iodinated X-ray contrast agents are considered to be nondegradable by microorganisms. The decomposition of the ionic X-ray contrast agents Diatrizoate (3,5-di(acetamido)-2,4,6-triiodobenzoic acid) and Iodipamide (3,3′-adipoyl-diimino-di(2,4,6-triiodobenzoic acid) and related triiodinated benzoates (Acetrizoate [3-acetylamino-2,4,6-triiodobenzoic acid] and Aminotrizoate [3-amino-2,4,6-triiodobenzoic acid]) by Trametes versicolor has been investigated. The fungus was able to transform all tested triiodinated benzoates cometabolically. During transformation of these compounds, iodide was released, but deiodination was not complete. T. versicolor liberated traces of 14CO2 from uniformly ring-14C-labeled Diatrizoate (3,5-di(acetamido)-2,4,6-triiodobenzoate). Various extracellular metabolites were detected during transformation of the different substances. In the transformation of Diatrizoate, the three main metabolites were identified as 3,5-di(acetamido)-2,6-diiodobenzoic acid, 3,5-di(acetamido)-2,4-diiodobenzoic acid, and 3,5-di(acetamido)-2-iodobenzoic acid, suggesting reductive deiodinations in steps as initial transformation steps. PMID:9687487
Biotechnological Production of Caffeic Acid by Bacterial Cytochrome P450 CYP199A2
Arai, Yuka; Kino, Kuniki
2012-01-01
Caffeic acid is a biologically active molecule that has various beneficial properties, including antioxidant, anticancer, and anti-inflammatory activities. In this study, we explored the catalytic potential of a bacterial cytochrome P450, CYP199A2, for the biotechnological production of caffeic acid. When the CYP199A2 enzyme was reacted with p-coumaric acid, it stoichiometrically produced caffeic acid. The crystal structure of CYP199A2 shows that Phe at position 185 is situated directly above, and only 6.35 Å from, the heme iron. This F185 residue was replaced with hydrophobic or hydroxylated amino acids using site-directed mutagenesis to create mutants with novel and improved catalytic properties. In whole-cell assays with the known substrate of CYP199A2, 2-naphthoic acid, only the wild-type enzyme hydroxylated 2-naphthoic acid at the C-7 and C-8 positions, whereas all of the active F185 mutants exhibited a preference for C-5 hydroxylation. Interestingly, several F185 mutants (F185V, F185L, F185I, F185G, and F185A mutants) also acquired the ability to hydroxylate cinnamic acid, which was not hydroxylated by the wild-type enzyme. These results demonstrate that F185 is an important residue that controls the regioselectivity and the substrate specificity of CYP199A2. Furthermore, Escherichia coli cells expressing the F185L mutant exhibited 5.5 times higher hydroxylation activity for p-coumaric acid than those expressing the wild-type enzyme. By using the F185L whole-cell catalyst, the production of caffeic acid reached 15 mM (2.8 g/liter), which is the highest level so far attained in biotechnological production of this compound. PMID:22729547
High Energy Halogen Chemistry.
1978-01-01
underwent addition of triflic acid and of hydrochloric acid . The oxetane was polymerized ~zith phosphorous pentaflucride to ~lve a polymer stable to 2900...in aqueous dioxane . The oxetane was not affected by boron trifluoride etherate In chloroform, or by methanolic solutions of sulfuric or triflic acids ...concentrated hydrochloric acid to give 3-chloro-2-fluoro-2-nitro-l-propanol. NO • i 2 NO2OH CF I + CF SOH— 3 CF SO OCH CCH OH O OH ~ 3 3 2 2~ 2 F NO NO
Yang, Xinchao; Wang, Ke; Zhang, Jianhua; Tang, Lei; Mao, Zhonggui
2016-11-01
Recently, the integrated ethanol-methane fermentation process has been studied to prevent wastewater pollution. However, when the anaerobic digestion reaction runs poorly, acetic acid will accumulate in the recycling water. In this paper, we studied the effect of low concentration of acetic acid (≤25 mM) on ethanol fermentation at different initial pH values (4.2, 5.2 or 6.2). At an initial pH of 4.2, ethanol yields increased by 3.0% and glycerol yields decreased by 33.6% as the acetic acid concentration was increased from 0 to 25 mM. Raising the concentration of acetic acid to 25 mM increased the buffering capacity of the medium without obvious effects on biomass production in the cassava medium. Acetic acid was metabolized by Saccharomyces cerevisiae for the reason that the final concentration of acetic acid was 38.17% lower than initial concentration at pH 5.2 when 25 mM acetic acid was added. These results confirmed that a low concentration of acetic acid in the process stimulated ethanol fermentation. Thus, reducing the acetic acid concentration to a controlled low level is more advantageous than completely removing it.
Bornik, Maria-Anna; Kroh, Lothar W
2013-04-10
Thermal treatment of an aqueous solution of D-galacturonic acid at pH 3, 5, and 8 led to rapid browning of the solution and to the formation of carbocyclic compounds such as reductic acid (2,3-dihydroxy-2-cyclopenten-1-one), DHCP (4,5-dihydroxy-2-cyclopenten-1-one), and furan-2-carbaldehyde, as degradation products in weak acidic solution. Studies on their formation revealed 2-ketoglutaraldehyde as their common key intermediate. Norfuraneol (4-hydroxy-5-methyl-3-(2H)-furanone) is a typical alkaline degradation product and formed after isomerization. Further model studies revealed reductic acid as an important and more browning active compound than furan-2-carbaldehyde, which led to a red color of the model solution. This red-brown color is also characteristic of thermally treated uronic acid solutions.
Cuende, J; Moreno, S; Bolaños, J P; Almeida, A
2008-05-22
In neuroblastoma cells, retinoic acid induces cell cycle arrest and differentiation through degradation of the F-box protein, Skp2, and stabilization of cyclin-dependent kinase inhibitor, p27. However, the mechanism responsible for retinoic acid-mediated Skp2 destabilization is unknown. Since Skp2 is degraded by anaphase-promoting complex (APC)(Cdh1), here we studied whether retinoic acid promotes differentiation of human SH-SY5Y neuroblastoma cells by modulating Cdh1. We found that retinoic acid induced the nuclear accumulation of Cdh1 that paralleled Skp2 destabilization and p27 accumulation. The mRNA and protein abundance of Rae1-a nuclear export factor that limits APC(Cdh1) activity in mitosis-decreased upon retinoic acid-induced inhibition of neuroblastoma cell proliferation. Furthermore, either Rae1 overexpression or Cdh1 inhibition promoted Skp2 accumulation, p27 destabilization and prevented retinoic acid-induced cell cycle arrest and differentiation. Conversely, inhibition of Rae1 accelerated retinoic acid-induced differentiation. Thus, retinoic acid downregulates Rae1, hence facilitating APC(Cdh1)-mediated Skp2 degradation leading to the arrest of cell cycle progression and neuroblastoma differentiation.
One-pot synthesis of bioactive cyclopentenones from α-linolenic acid and docosahexaenoic acid.
Maynard, Daniel; Müller, Sara Mareike; Hahmeier, Monika; Löwe, Jana; Feussner, Ivo; Gröger, Harald; Viehhauser, Andrea; Dietz, Karl-Josef
2018-04-01
Oxidation products of the poly-unsaturated fatty acids (PUFAs) arachidonic acid, α-linolenic acid and docosahexaenoic acid are bioactive in plants and animals as shown for the cyclopentenones prostaglandin 15d-PGJ 2 and PGA 2 , cis-(+)-12-oxophytodienoic acid (12-OPDA), and 14-A-4 neuroprostane. In this study an inexpensive and simple enzymatic multi-step one-pot synthesis is presented for 12-OPDA, which is derived from α-linolenic acid, and the analogous docosahexaenoic acid (DHA)-derived cyclopentenone [(4Z,7Z,10Z)-12-[[-(1S,5S)-4-oxo-5-(2Z)-pent-2-en-1yl]-cyclopent-2-en-1yl] dodeca-4,7,10-trienoic acid, OCPD]. The three enzymes utilized in this multi-step cascade were crude soybean lipoxygenase or a recombinant lipoxygenase, allene oxide synthase and allene oxide cyclase from Arabidopsis thaliana. The DHA-derived 12-OPDA analog OCPD is predicted to have medicinal potential and signaling properties in planta. With OCPD in hand, it is shown that this compound interacts with chloroplast cyclophilin 20-3 and can be metabolized by 12-oxophytodienoic acid reductase (OPR3) which is an enzyme relevant for substrate bioactivity modulation in planta. Copyright © 2017 Elsevier Ltd. All rights reserved.
Identification of the fatty acid activation site on human ClC-2.
Cuppoletti, John; Tewari, Kirti P; Chakrabarti, Jayati; Malinowska, Danuta H
2017-06-01
Fatty acids (including lubiprostone and cobiprostone) are human ClC-2 (hClC-2) Cl - channel activators. Molecular and cellular mechanisms underlying this activation were examined. Role of a four-amino acid PKA activation site, RGET 691 , of hClC-2 was investigated using wild-type (WT) and mutant (AGET, RGEA, and AGAA) hClC-2 expressed in 293EBNA cells as well as involvement of PKA, intracellular cAMP concentration ([cAMP] i ), EP 2 , or EP 4 receptor agonist activity. All fatty acids [lubiprostone, cobiprostone, eicosatetraynoic acid (ETYA), oleic acid, and elaidic acid] caused significant rightward shifts in concentration-dependent Cl - current activation (increasing EC 50 s) with mutant compared with WT hClC-2 channels, without changing time and voltage dependence, current-voltage rectification, or methadone inhibition of the channel. As with lubiprostone, cobiprostone activation of hClC-2 occurred with PKA inhibitor (myristoylated protein kinase inhibitor) present or when using double PKA activation site (RRAA 655 /RGEA 691 ) mutant. Cobiprostone did not activate human CFTR. Fatty acids did not increase [cAMP] i in hClC-2/293EBNA or T84 cells. Using T84 CFTR knockdown cells, cobiprostone increased hClC-2 Cl - currents without increasing [cAMP] i, while PGE 2 and forskolin-IBMX increased both. Fatty acids were not agonists of EP 2 or EP 4 receptors. L-161,982, a supposed EP 4 -selective inhibitor, had no effect on lubiprostone-activated hClC-2 Cl - currents but significantly decreased T84 cell barrier function measured by transepithelial resistance and fluorescent dextran transepithelial movement. The present findings show that RGET 691 of hClC-2 (possible binding site) plays an important functional role in fatty acid activation of hClC-2. PKA, [cAMP] i , and EP 2 or EP 4 receptors are not involved. These studies provide the molecular basis for fatty acid regulation of hClC-2. Copyright © 2017 the American Physiological Society.
Effects of multivalent cations on cell wall-associated acid phosphatase activity
DOE Office of Scientific and Technical Information (OSTI.GOV)
Tu, S.I.; Brouillette, J.N.; Nagahashi, G.
1988-09-01
Primary cell walls, free from cytoplasmic contamination were prepared from corn (Zea mays L.) roots and potato (Solanum tuberosum) tubers. After EDTA treatment, the bound acid phosphatase activities were measured in the presence of various multivalent cations. Under the conditions of minimized Donnan effect and at pH 4.2, the bound enzyme activity of potato tuber cell walls (PCW) was stimulated by Cu/sup 2 +/, Mg/sup 2 +/, Za/sup 2 +/, and Mn/sup 2 +/; unaffected by Ba/sup 2 +/, Cd/sup 2 +/, and Pb/sup 2 +/; and inhibited by Al/sup 3 +/. The bound acid phosphatase of PCW was stimulatedmore » by a low concentration but inhibited by a higher concentration of Hg/sup 2 +/. On the other hand, in the case of corn root cells walls (CCW), only inhibition of the bound acid phosphatase by Al/sup 3 +/ and Hg/sup 2 +/ was observed. Kinetic analyses revealed that PCW acid phosphatase exhibited a negative cooperativity under all employed experimental conditions except in the presence of Mg/sup 2 +/. In contrast, CCW acid phosphatase showed no cooperative behavior. The presence of Ca/sup 2 +/ significantly reduced the effects of Hg/sup 2 +/ or Al/sup 3 +/, but not Mg/sup 2 +/, to the bound cell wall acid phosphatases. The salt solubilized (free) acid phosphatases from both PCW and CCW were not affected by the presence of tested cations except for Hg/sup 2 +/ or Al/sup 3 +/ which caused a Ca/sup 2 +/-insensitive inhibition of the enzymes. The induced stimulation or inhibition of bound acid phosphatases was quantitatively related to cation binding in the cell wall structure.« less
Zugaza, J L; Casabiell, X A; Bokser, L; Casanueva, F F
1995-02-06
EGFR-T17 cells were pretreated with oleic acid and 5-10 minutes later stimulated with EGF, to study if early ionic signals are instrumental in inducing metabolic cellular response. Oleic acid blocks EGF-induced [Ca2+]i rise and Ca2+ influx without altering 2-deoxyglucose and 2-aminobutiryc acid uptake nor acute, nor chronically. Oleic acid it is shown, in the first minutes favors the entrance of both molecules to modify the physico-chemical membrane state. On the other hand, oleic acid is unable to block protein synthesis. The results suggest that EGF-induced Ins(1,4,5)P3/Ca2+ pathway does not seem to be decisive in the control of cellular metabolic activity.
NASA Technical Reports Server (NTRS)
Lerner, Narcinda R.; Cooper, George W.; Chang, Sherwood (Technical Monitor)
1996-01-01
The Strecker synthesis, R2C=O + HCN + NH3 yields R2C(NH2)CN + H2O yields R2C(NH2)CO2H has been proposed as a source of amino acids in meteorites. The detection of carbonlyl compounds, the precursors of the amino acids in the Strecker synthesis, and a-hydroxy acids, important by-products of the Strecker synthesis, in the Murchison meteorite supports this conjecture. However, the following observations raise questions about the Strecker synthesis as the source of a-amino and a-hydroxy acids in Murchison: a) Imino acetic acids are also important by-products of the Strecker synthesis and have not been reported in Murchison. b) a-aminisobutyric acid (AIBA) is one of the most abundant amino acids in Murchison but the Strecker synthesis conducted at room temperature produced only small amounts of AIBA relative to other amino acids. c) If the a-amino and a-hydroxy acids observed in Murchison arose from a common precursor this ought to be reflected in their relative abundances, but the straight chain a-hydroxy acids appeared to be relatively abundant compared with the analogous a-amino acids. In order to address question a) we have examined a non-hydrolyzed aqueous extract of the Murchison meteorite. Imino di acetic acid, Imino propionic acetic acid and Imino butyric acetic acid (both isomers) have been identified in this fraction. The relative abundances of amino acids and imino acetic acids in this fraction are consistent with a Strecker synthesis at low temperature (263 K) as a origin of both the amino acids and the imino acetic acids found on Murchison. To deal with questions b) and c) we have carried out laboratory simulations of the Strecker synthesis. The starting concentrations for carbonlyl compounds used were based on estimates of what these concentrations might have been on the parent body. for the carbonyl compounds this estimate was determined by the amount of carbonyl compound found on Murchison plus the amounts of the corresponding amino acid and hydroxy acid found on Murchison and the rock to water ratio estimated by Clayton and Mayeda (1984). The cyanide concentration was that estimated by Peltzer et al. (1984). The ammonia concentration and pH were varied. We studied these mixtures at 298 K and 263 K. We found that high relative abundances of AIBA were produced at 263 K but not at 298 K. We only produced a-methyl a-amino hydroxy acids at 263 K with no initial ammonia. The abundances of a-amino acids, a-hydroxy acids and imino acids found on Murchison are consistent with a Strecker synthesis which took place at low temperature and with a low concentration of ammonia.
Prasadani, W. Chaturi; Senanayake, Chaturi M.; Jayathilaka, Nimanthi; Ekanayake, Sagarika
2017-01-01
Polyphenolic antioxidants are mainly absorbed through passive paracellular permeation regulated by tight junctions. Some fatty acids are known to modulate tight junctions. Fatty acids resulting from the digestion of edible oils may improve the absorption of polyphenolic antioxidants. Therefore, we explored the effect of three edible oils on the intestinal absorption of caffeic acid. Rats were fed with soybean oil and caffeic acid dissolved in distilled water. Caffeic acid contents in the plasma collected up to 1 hr were quantified. The experiment was repeated with coconut oil and olive oil. Component fatty acids of the oils were individually tested in vitro for their effect on permeability of caffeic acid using Caco-2 cell monolayers. Highest absorption of caffeic acid was observed in animals fed with coconut oil. In vitro transport percentages of caffeic acid in 2.5 mmol/L solutions of fatty acids were 22.01±0.12 (lauric), 15.30 ± 0.25 (myristic acid), 13.59 ± 0.35 (linoleic acid), 3.70 ± 0.09 (oleic acid) and 0.10–2.0 (all other fatty acids). Lauric acid and myristic acid are the two major fatty acids present in coconut oil. Therefore, these fatty acids may contribute to the higher absorption of caffeic acid in the presence of coconut oil. PMID:28617858
NASA Astrophysics Data System (ADS)
SempéRé, Richard; Kawamura, Kimitaka
2003-06-01
Marine aerosol samples were collected during a western Pacific cruise covering the latitude range between 35°N and 40°S (140°E-180°E). They were analyzed for total carbon (TC), total nitrogen (TN), water-soluble organic carbon (WSOC) along with the molecular distributions of C2-C10 α, ω-dicarboxylic acids, and related polar compounds, mainly, ω-oxocarboxylic acids (C2-C9) and α-dicarbonyls (C2-C3). Oxalic acid (C2) was the most abundant followed by malonic (C3) and succinic (C4) acids. The total diacid concentration range was 7-605 ng m-3 (av. 85 ng m-3) and the diacid-carbon accounted for 2-15% (average 8%) of WSOC which comprised 29-55% (average 40%) of TC. Dry depositions of total diacids over the northern and southern Pacific Ocean were estimated to be 256-1907 μg m-2 yr-1 (average 735; n = 4) and 22-396 μg m-2 yr-1 (average 134; n = 14), respectively, whereas the air-to-sea flux of oxalic acid was 18-1351 μg m-2 yr-1 (average 466 μg m-2 yr-1) and 7.5-275 μg m-2 yr-1 (average 75 μg m-2 yr-1) in the Northern and Southern Hemispheres. We observed that the concentration ratios of diacid-C/WSOC, azelaic acid (C9)/ω-oxononanoic acid, maleic acid (iC4cis)/fumaric (iC4trans) acid and succinic acid (C4)/total diacids were correlated with air temperature. These findings showed that the intensity of photochemical oxidation reactions and thus the variation in sunlight intensity characterized here by air temperature, significantly control the molecular distribution of water-soluble organic compounds during the long-range transport of anthropogenic and/or biogenic higher molecular weight organic compounds.
Lindh, Christian H; Littorin, Margareta; Amilon, Asa; Jönsson, Bo A G
2008-01-01
Phenoxyacetic acids are widely used herbicides. The toxicity of phenoxyacetic acids is debated, but high-level exposure has been shown to be hepatotoxic as well as nephrotoxic in animal studies. An inter-species difference in toxic effects has been found, with dogs particularly susceptible. In this study a method using liquid chromatography/triple quadrupole mass spectrometry (LC/MS/MS) is described for the analysis of 4-chloro-2-methylphenoxyacetic acid (MCPA), and its metabolite 4-chloro-2-hydroxymethylphenoxyacetic acid (HMCPA), 2,4-dichlorophenoxyacetic acid (2,4-D), and 2,4,5-trichlorophenoxyacetic acid (2,4,5-T) in human urine. The urine samples were treated by acid hydrolysis to degrade possible conjugations. The sample preparation was performed using solid-phase extraction. Analysis was carried out using selected reaction monitoring (SRM) in the negative ion mode. Quantification of the phenoxyacetic acids was performed using [(2)H(3)]-labeled MCPA and 2,4-D as internal standards. The method was linear in the range 0.05-310 ng/mL urine and has a within-run precision of 2-5%. The between-run precision in lower concentration ranges was between 6-15% and between 2-8% in higher concentration ranges. The limit of detection was determined to 0.05 ng/mL. The metabolites in urine were found to be stable during storage at -20 degrees C. To validate the phenoxyacetic acids as biomarkers of exposure, the method was applied in a human experimental oral exposure to MCPA, 2,4-D and 2,4,5-T. Two healthy volunteers received 200 microg of each phenoxyacetic acid in a single oral dose followed by urine sampling for 72 h post-exposure. After exposure, between 90 and 101% of the dose was recovered in the urine. In the female subject, 23%, and in the male subject 17%, of MCPA was excreted as HMCPA. Copyright (c) 2007 John Wiley & Sons, Ltd.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Louie, Matthew K.; Francisco, Joseph S.; Verdicchio, Marco
2015-05-14
The hydrolysis of ketene (H2C=C=O) to form acetic acid involving two water molecules and also separately in the presence of one to two water molecules and formic acid (FA) was investigated. Our results show that, while the currently accepted indirect mechanism, involving addition of water across the carbonyl C=O bond of ketene to form an ene-diol followed by tautomerization of the ene-diol to form acetic acid, is the preferred pathway when water alone is present, with formic acid as catalyst, addition of water across the ketene C=C double bond to directly produce acetic acid becomes the kinetically favored pathway formore » temperatures below 400 K. We find not only that the overall barrier for ketene hydrolysis involving one water molecule and formic acid (H2C2O + H2O + FA) is significantly lower than that involving two water molecules (H2C2O + 2H(2)O) but also that FA is able to reduce the barrier height for the direct path, involving addition of water across the C=C double bond, so that it is essentially identical with (6.4 kcal/mol) that for the indirect ene-diol formation path involving addition of water across the C=O bond. For the case of ketene hydrolysis involving two water molecules and formic acid (H2C2O + 2H(2)O + FA), the barrier for the direct addition of water across the C=C double bond is reduced even further and is 2.5 kcal/mol lower relative to the ene-diol path involving addition of water across the C=O bond. In fact, the hydrolysis barrier for the H2C2O + 2H(2)O + FA reaction through the direct path is sufficiently low (2.5 kcal/mol) for it to be an energetically accessible pathway for acetic acid formation under atmospheric conditions. Given the structural similarity between acetic and formic acid, our results also have potential implications for aqueous-phase chemistry. Thus, in an aqueous environment, even in the absence of formic acid, though the initial mechanism for ketene hydrolysis is expected to involve addition of water across the carbonyl bond as is currently accepted, the production and accumulation of acetic acid will likely alter the preferred pathway to one involving addition of water across the ketene C=C double bond as the reaction proceeds.« less
Simoni, S.; Klinke, S.; Zipper, C.; Angst, W.; Kohler, H. E.
1996-01-01
Rhodococcus rhodochrous PB1 was isolated from compost soil by selective culture with racemic 3-phenylbutyric acid as the sole carbon and energy source. Growth experiments with the single pure enantiomers as well as with the racemate showed that only one of the two enantiomers, (R)-3-phenylbutyric acid, supported growth of strain PB1. Nevertheless, (S)-3-phenylbutyric acid was cometabolically transformed to, presumably, (S)-3-(2,3-dihydroxyphenyl)butyric acid (the absolute configuration at the C-3 atom is not known yet) by (R)-3-phenylbutyric acid-grown cells of strain PB1, as shown by (sup1)H nuclear magnetic resonance spectroscopy of the partially purified compound and gas chromatography-mass spectrometry analysis of the trimethylsilyl derivative. Oxygen uptake rates suggest that either 3-phenylpropionic acid or cinnamic acid (trans-3-phenyl-2-propenoic acid) is the substrate for aromatic ring hydroxylation. This view is substantiated by the fact that 3-(2,3-dihydroxyphenyl)propionic acid was a substrate for meta cleavage in cell extracts of (R)-3-phenylbutyric acid-grown cells of strain PB1. Gas chromatography-mass spectrometry analysis of trimethylsilane-treated ethyl acetate extracts of incubation mixtures showed that both the meta-cleavage product, 2-hydroxy-6-oxo-2,4-nonadiene-1,9-dicarboxylic acid, and succinate, a hydrolysis product thereof, were formed during such incubations. PMID:16535265
A simple and specific procedure to permeabilize the plasma membrane of Schizosaccharomyces pombe.
Chardwiriyapreecha, Soracom; Hondo, Kana; Inada, Hiroko; Chahomchuen, Thippayarat; Sekito, Takayuki; Iwaki, Tomoko; Kakinuma, Yoshimi
2009-09-01
Cu(2+)-treatment is a useful technique in selectively permeabilizing the fungal plasma membrane. We describe herein a practical application with Schizosaccharomyces pombe. Incubation of cells with 0.5 mM CuCl(2) at 30 degrees C for 20 min induced efficient leakage of cytosolic constituents. The kinetic characteristics of the calcium and amino acid flux from Cu(2+)-treated S. pombe cells suggested that the Cu(2+) treatment permeabilized the plasma membrane without loss of vacuolar function. As a further application of the method, the amino acid contents of Cu(2+)-treated and untreated cells were also determined. The amino acid pool of Cu(2+)-treated wild-type cells was enriched in basic amino acids but not in acidic amino acids, as is characteristic of the vacuolar amino acid pool of fungi, including Saccharomyces cerevisiae and Neurosporra crassa. The amino acid pool of the S. pombe V-ATPase mutant vma1Delta was also successfully determined. We conclude that the vacuolar amino acid pool of S. pombe can be measured using Cu(2+)-treated cells. The method is simple, inexpensive, and rapid relative to the isolation of vacuolar vesicles, making it useful in estimating vacuolar pools and transport across the vacuolar membrane.
Diphasic acido-basic properties of D(octylphenyl)phosphoric acid (DOPPA)
DOE Office of Scientific and Technical Information (OSTI.GOV)
Sella, C.; Cote, G.; Bauer, D.
1995-07-01
In the first part of this work, the diphasic acido-basic constant (pka*) of di(octylphenyl)phosphoric acid, denoted hereafter DOPPA or HL, is determined from its experimental diphasic neutralization curve. The pka* value of DOPPA appears to be equal to 2.6 in the presence of 1 mol/dm{sup 3} sodium salt. Such a value is significantly lower than that previously determined for di(2-ethylhexyl) phosphoric acid (DEHPA, pka* = 5.2), 2-ethylhexylphosphonic acid, mono-2-ethylhexyl ester (PC88A, pka* = 7.1) and di(2,4,4-trimethylpentyl)phosphinic acid (CYANEX 272, pka* = 8.7). DOPPA (HL) is definitely more acidic than the other organophosphorus acids because its acidic proton can be easilymore » exchanged with sodium cation to form Na{sup +}HL{sub 2}{sup -} species in organic phase. In the second and final part of the work, molecular modelling is used to model the dimers of various organophosphorus acids. A structure-activity relationship is obtained between the association energies of modelled dimers and their diphasic acido-basic constants. This relationship is then used for predicting the pka* values of DOPPOA and DOPPIA which are the phosphonic and phosphinic analogs of DOPPA, respectively. 16 refs., 5 figs., 4 tabs.« less
Microbial CH4 and N2O Consumption in Acidic Wetlands
Kolb, Steffen; Horn, Marcus A.
2012-01-01
Acidic wetlands are global sources of the atmospheric greenhouse gases methane (CH4), and nitrous oxide (N2O). Consumption of both atmospheric gases has been observed in various acidic wetlands, but information on the microbial mechanisms underlying these phenomena is scarce. A substantial amount of CH4 is consumed in sub soil by aerobic methanotrophs at anoxic–oxic interfaces (e.g., tissues of Sphagnum mosses, rhizosphere of vascular plant roots). Methylocystis-related species are likely candidates that are involved in the consumption of atmospheric CH4 in acidic wetlands. Oxygen availability regulates the activity of methanotrophs of acidic wetlands. Other parameters impacting on the methanotroph-mediated CH4 consumption have not been systematically evaluated. N2O is produced and consumed by microbial denitrification, thus rendering acidic wetlands as temporary sources or sinks for N2O. Denitrifier communities in such ecosystems are diverse, and largely uncultured and/or new, and environmental factors that control their consumption activity are unresolved. Analyses of the composition of N2O reductase genes in acidic wetlands suggest that acid-tolerant Proteobacteria have the potential to mediate N2O consumption in such soils. Thus, the fragmented current state of knowledge raises open questions concerning methanotrophs and denitrifiers that consume atmospheric CH4 and N2O in acidic wetlands. PMID:22403579
Tabuchi, Yohei; Gotoh, Kazuma; Ishida, Hiroyuki
2015-11-01
The crystal structures of three hydrogen-bonded co-crystals of 4-alk-oxy-benzoic acid-1,2-bis-(pyridin-4-yl)ethane (2/1), namely, 2C9H10O3·C12H12N2, (I), 2C10H12O3·C12H12N2, (II), and 2C11H14O3·C12H12N2, (III), have been determined at 93, 290 and 93 K, respectively. In (I), the asymmetric unit consists of one 4-eth-oxy-benzoic acid mol-ecule and one half-mol-ecule of 1,2-bis-(pyridin-4-yl)ethane, which lies on an inversion centre. In (II) and (III), the asymmetric units each comprise two crystallographically independent 4-alk-oxy-benzoic acid mol-ecules and one 1,2-bis-(pyridin-4-yl)ethane mol-ecule. In each crystal, the two components are linked by O-H⋯N hydrogen bonds, forming a linear hydrogen-bonded 2:1unit of the acid and the base. Similar to the structure of 2:1 unit of (I), the units of (II) and (III) adopt nearly pseudo-inversion symmetry. The 2:1 units of (I), (II) and (III) are linked via C-H⋯O hydrogen bonds, forming tape structures.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Oh, Sang-Keun; Yoon, Joonseon; Choi, Gyung Ja
Highlights: •The CaHB1 is a nuclear factor, belonging to HD-Zip proteins. •SA and ET, as signal molecules, modulate CaHB1-mediated responses. •Overexpression of CaHB1 in tomato resulted in a thicker cell wall. •CaHB1-transgenic tomato confers resistance to Phytophthora infestans. •CaHB1 enhanced tolerance to saline stress in tomato. -- Abstract: Homeodomain-leucine zipper (HD-Zip) family proteins are unique to plants, but little is known about their role in defense responses. CaHB1 is a nuclear factor in peppers, belonging to subfamily II of HD-Zip proteins. Here, we determined the role of CaHB1 in the defense response. CaHB1 expression was induced when pepper plants weremore » challenged with Phytophthora capsici, a plant pathogen to which peppers are susceptible, or environmental stresses such as drought and salt stimuli. CaHB1 was also highly expressed in pepper leaves following application of SA, whereas ethephon and MeJA had a moderate effect. To further investigate the function of CaHB1 in plants, we performed gain-of-function study by overexpression of CaHB1 in tomato. CaHB1-transgenic tomatoes showed significant growth enhancement including increased leaf thickness and enlarged cell size (1.8-fold larger than control plants). Microscopic analysis revealed that leaves from CaHB1-transgenic plants had thicker cell walls and cuticle layers than those from controls. Moreover, CaHB1-transgenic plants displayed enhanced resistance against Phytophthora infestans and increased tolerance to salt stress. Additionally, RT-PCR analysis of CaHB1-transgenic tomatoes revealed constitutive up-regulation of multiple genes involved in plant defense and osmotic stress. Therefore, our findings suggest roles for CaHB1 in development, salt stress, and pathogen defense.« less
Khan, Anwar A.; Karssen, C. M.
1980-01-01
Factors controlling the establishment and removal of secondary dormancy in Chenopodium bonus-henricus L. seeds were investigated. Unchilled seeds required light for germination. A moist-chilling treatment at 4 C for 28 to 30 days removed this primary dormancy. Chilled seeds now germinated in the dark. When chilled seeds were held in the dark in −8.6 bars polyethylene glycol 6000 solution at 15 C or in water at 29 C a secondary dormancy was induced which increased progressively with time as determined by subsequent germination. These seeds now failed to germinate under the condition (darkness) which previously allowed their germination. Continuous light or daily brief red light irradiations during prolonged imbibition in polyethylene glycol solution at 15 C or in water at 29 C prevented the establishment of the secondary dormancy and caused an advancement of subsequent germination. Far red irradiations immediately following red irradiation reestablished the secondary dormancy indicating phytochrome participation in “pregerminative” processes. The growth regulator combination, kinetin + ethephon + gibberellin A4+A7 (GA4+7), and to a relatively lesser extent GA4+7, was effective in preventing the establishment of the secondary dormancy and in advancing the germination or emergence time. Following the establishment of the secondary dormancy by osmotic or high temperature treatments the regulator combination was relatively more active than light or GA4+7 in removing the dormancy. Prolonged dark treatment at 29 C seemed to induce changes that were partially independent of light or GA4+7 control. The data presented here indicate that changes during germination preventing dark treatment determine whether the seed will germinate, show an advancement effect, or will become secondarily dormant. These changes appear to be modulated by light and hormones. PMID:16661382
Guo, Qiaosheng; Fang, Hailing; Shen, Haijin
2010-05-01
To evaluate the quality of Flos Chrysanthemi Indici which produced in twenty-two different producing places. Chlorogenic acid and caffeic acid were analyzed on a Shim-pack C8 colunm (4.6 mm x 250 mm, 5 microm) eluted with the mobile phase consisted of acetonitrile-0.5% phosphoric acid( 19:81). The detection wavelength was set at 326 nm. Linarin were eluted with the mobile phase consisted of methanol-water-acetic acid(26: 23: 1). The detection wavelength was set at 334 nm. The column temperature was 25 degrees C. The flow rate was 1.0 mL x min . The linear response ranged within 2.5-50 microg for chlorogenic acid (r = 0.998), 2.5-25 microg for caffeic acid (r = 0.998) and 4.97-41.47 microg for linarin (r = 0.999), respectively. Recoveries were 100.8% with RSD 2.1% for chlorogenic acid, 96.2% with RSD 2.3% for caffeic acid and 103.7% with RSD 1.8% for linarin. There was a significant difference in the content of chlorogenic acid, caffeic acid, linarin among the samples. The content of chlorogenic in the sample from Fengdou Chongqing city was the highest in those from other places. The content of caffeic acid in the all samples is very low. The content of linarin in the samples from Jiangsu province and Anhui province almost reached the national standard in pharmacopoeia.
Comparison of inhibition effects of some benzoic acid derivatives on sheep heart carbonic anhydrase
NASA Astrophysics Data System (ADS)
Kiliç, Deryanur; Yildiz, Melike; Şentürk, Murat; Erdoǧan, Orhan; Küfrevioǧlu, Ömer Irfan
2016-04-01
Carbonic anhydrase (CA) is a family of metalloenzymes that requires Zn as a cofactor and catalyze the quick conversion of CO2 to HCO3- and H+. Inhibitors of the carbonic anhydrases (CAs) have medical usage of significant diseases such as glaucoma, epilepsy, gastroduodenal ulcers, acid-base disequilibria and neurological disorders. In the present study, inhibition of CA with some benzoic derivatives (1-6) were investigated. Sheep heart CA (shCA) enzyme was isolated by means of designed affinity chromatography gel (cellulose-benzyl-sulfanylamide) 42.45-fold in a yield of 44 % with 564.65 EU/mg. Purified shCA enzyme was used in vitro studies. In the studies, IC50 values were calculated for 3-aminobenzoic acid (1), 4-aminobenzoic acid (2), 2-hydroxybenzoic acid (3), 2-benzoylbenzoic acid (4), 2,3-dimethoxybenzoic acid (5), and 3,4,5-trimethoxybenzoic acid (6), showing the inhibition effects on the purified enzyme. Such molecules can be used as pioneer for discovery of novel effective CA inhibitors for medicinal chemistry applications.
Fatty acid transport and transporters in muscle are critically regulated by Akt2.
Jain, Swati S; Luiken, Joost J F P; Snook, Laelie A; Han, Xiao Xia; Holloway, Graham P; Glatz, Jan F C; Bonen, Arend
2015-09-14
Muscle contains various fatty acid transporters (CD36, FABPpm, FATP1, FATP4). Physiological stimuli (insulin, contraction) induce the translocation of all four transporters to the sarcolemma to enhance fatty acid uptake similarly to glucose uptake stimulation via glucose transporter-4 (GLUT4) translocation. Akt2 mediates insulin-induced, but not contraction-induced, GLUT4 translocation, but its role in muscle fatty acid transporter translocation is unknown. In muscle from Akt2-knockout mice, we observed that Akt2 is critically involved in both insulin-induced and contraction-induced fatty acid transport and translocation of fatty acid translocase/CD36 (CD36) and FATP1, but not of translocation of fatty acid-binding protein (FABPpm) and FATP4. Instead, Akt2 mediates intracellular retention of both latter transporters. Collectively, our observations reveal novel complexities in signaling mechanisms regulating the translocation of fatty acid transporters in muscle. Copyright © 2015 Federation of European Biochemical Societies. Published by Elsevier B.V. All rights reserved.
Wan, Jianchun; Hu, Songyou; Ni, Kefeng; Chang, Guifang; Sun, Xiangjun; Yu, Liangli
2016-01-01
The structure of dietary triacylglycerols is thought to influence fatty acid and calcium absorption, as well as intestinal microbiota population of the host. In the present study, we investigated the impact of palmitic acid (PA) esterified at the sn-2 position on absorption of fatty acid and calcium and composition of intestinal microorganisms in rats fed high-fat diets containing either low sn-2 PA (12.1%), medium sn-2 PA (40.4%) or high sn-2 PA (56.3%), respectively. Fecal fatty acid profiles in the soaps were measured by gas chromatography (GC), while fecal calcium concentration was detected by ICP-MS. The fecal microbial composition was assessed using a 16S rRNA high-throughput sequencing technology and fecal short-chain fatty acids were detected by ion chromatograph. Dietary supplementation with a high sn-2 PA fat significantly reduced total fecal contents of fatty acids soap and calcium compared with the medium or low sn-2 PA fat groups. Diet supplementation with sn-2 PA fat did not change the entire profile of the gut microbiota community at phylum level and the difference at genera level also were minimal in the three treatment groups. However, high sn-2 PA fat diet could potentially improve total short-chain fatty acids content in the feces, suggesting that high dietary sn-2 PA fat might have a beneficial effect on host intestinal health.
75 FR 31713 - 2-Propenoic acid polymer, with 1,3-butadiene and ethenylbenzene; Tolerance Exemption
Federal Register 2010, 2011, 2012, 2013, 2014
2010-06-04
... acid polymer, with 1,3-butadiene and ethenylbenzene; Tolerance Exemption AGENCY: Environmental... requirement of a tolerance for residues of 2-propenoic acid polymer, with 1,3- butadiene and ethenylbenzene... residues of 2-propenoic acid polymer, with 1,3-butadiene and ethenylbenzene on food or feed commodities...
Panoutsopoulos, Georgios I
2004-01-01
2-Phenylethylamine is an endogenous amine, which acts as a neuromodulator of dopaminergic responses. Exogenous 2-phenylethylamine is found in certain foodstuffs and may cause toxic side-effects in susceptible individuals. The present investigation examined the metabolism of 2-phenylethylamine to phenylacetic acid, via phenylacetaldehyde, in freshly prepared and cryopreserved liver slices. Additionally, it compared the relative contribution of aldehyde oxidase, xanthine oxidase and aldehyde dehydrogenase by using specific inhibitors for each oxidizing enzyme. In freshly prepared and cryopreserved liver slices, phenylacetic acid was the main metabolite of 2-phenylethalamine. In freshly prepared liver slices, phenylacetic acid was completely inhibited by disulfiram (inhibitor of aldehyde dehydrogenase), whereas isovanillin (inhibitor of aldehyde oxidase) inhibited acid formation to a lesser extent and allopurinol (inhibitor of xanthine oxidase) had no effect. In cryopreserved liver slices, isovanillin inhibited phenylacetic acid by 85%, whereas disulfiram inhibited acid formation to a lesser extent and allopurinol had no effect. In liver slices, 2-phenylethylamine is rapidly oxidized to phenylacetic acid, via phenylacetaldehyde, by aldehyde dehydrogenase and aldehyde oxidase with no contribution from xanthine oxidase.
Fatty acids composition of Spanish black (Morus nigra L.) and white (Morus alba L.) mulberries.
Sánchez-Salcedo, Eva M; Sendra, Esther; Carbonell-Barrachina, Ángel A; Martínez, Juan José; Hernández, Francisca
2016-01-01
This research has determined qualitatively and quantitatively the fatty acids composition of white (Morus alba) and black (Morus nigra) fruits grown in Spain, in 2013 and 2014. Four clones of each species were studied. Fourteen fatty acids were identified and quantified in mulberry fruits. The most abundant fatty acids were linoleic (C18:2), palmitic (C16:0), oleic (C18:1), and stearic (C18:0) acids in both species. The main fatty acid in all clones was linoleic (C18:2), that ranged from 69.66% (MN2) to 78.02% (MA1) of the total fatty acid content; consequently Spanish mulberry fruits were found to be rich in linoleic acid, which is an essential fatty acid. The fatty acid composition of mulberries highlights the nutritional and health benefits of their consumption. Copyright © 2015 Elsevier Ltd. All rights reserved.
Kim, Hyun-Soo; Kim, Na-Rae; Choi, Wonja
2011-03-01
The effect of change in unsaturated fatty acid composition on ethanol tolerance in Saccharomyces cerevisiae overexpressing ScOLE1 (∆9 fatty acid desaturase gene of S. cerevisiae), CaFAD2 (∆12 fatty acid desaturase gene of Candida albicans), or CaFAD3 (ω3 fatty acid desaturase gene of C. albicans) was examined. ScOLE1 over-expression increased the total unsaturated fatty acid content and enhanced ethanol tolerance, compared with a control strain. In contrast, overexpression of CaFAD2 and CaFAD3, which led to production of linoleic acid (18:2) and α-linolenic acid (18:3), respectively, neither changed total unsaturated fatty acids nor enhanced ethanol tolerance. The total unsaturated fatty acid content rather than the degree of unsaturation is thus an important factor for ethanol tolerance.
NASA Astrophysics Data System (ADS)
Silbaugh, Trent L.; Boaventura, Jaime S.; Barteau, Mark A.
2016-08-01
The first quantitative surface acidity scale for Brønsted acids on a solid surface is presented through the use of titration-displacement and equilibrium experiments on anatase TiO2. Surface acidities of species on TiO2 correlated with gas phase acidities, as was previously observed in qualitative studies of Brønsted acid displacement on Ag(110), Cu(110) and Au(111). A 90% compression of the surface acidity scale relative to the gas phase was observed due to compensation from the covalent component of the conjugate base - surface bond. Adsorbed conjugate bases need not be completely anionic for correlations with gas phase acidities to hold. Positive and negative substituent effects, such as substituted fluorine and hydrocarbon sidechain dispersion interactions with the surface, may modify the surface acidity scale, in agreement with previous experimental and theoretical work on Au(111).
Amrutha, Balagopal; Sundar, Kothandapani; Shetty, Prathapkumar Halady
2017-10-01
Organic acids are known to be used as food preservatives due to their antimicrobial potential. This study evaluated the ability of three organic acids, namely, acetic acid, citric acid and lactic acid to manage E. coli and Salmonella sp. from fresh fruits and vegetables. Effect of these organic acids on biofilm forming ability and anti-quorum potential was also investigated. The effect of organic acids on inactivation of E. coli and Salmonella sp. on the surface of a selected vegetable (cucumber) was determined. The minimum inhibitory concentration of the organic acids were found to be 1.5, 2 and 0.2% in E. coli while it was observed to be 1, 1.5 and 1% in Salmonella sp. for acetic, citric and lactic acids respectively. Maximum inhibition of biofilm formation was recorded at 39.13% with lactic acid in E. coli and a minimum of 22.53% with citric acid in Salmonella sp. EPS production was affected in E. coli with lactic acid showing reduction by 13.42% while citric acid and acetic acid exhibited only 6.25% and 10.89% respectively. Swimming and swarming patterns in E. coli was notably affected by both acetic and lactic acids. Lactic and acetic acids showed higher anti-quorum sensing (QS) potential when compared to citric acid. 2% lactic acid showed a maximum inhibition of violacein production by 37.7%. Organic acids can therefore be used as potential quorum quenching agents in food industry. 2% lactic acid treatment on cucumber demonstrated that it was effective in inactivating E. coli and Salmonella sp. There was 1 log reduction in microbial count over a period of 6 days after the lactic acid treatment. Thus, organic acids can act as effective potential sanitizers in reducing the microbial load associated with fresh fruits and vegetables. Copyright © 2017 Elsevier Ltd. All rights reserved.
Armaly, Ahlam M; Bar, Sukanta; Schindler, Corinna S
2017-08-04
The development of acid chlorides as formal dianion linchpin reagents that enable access to cyclic 2-alkyl- and 2-acyl-1,3-alkanediones from dicarboxylic acids is described herein. Mechanistic experiments relying on 13 C-labeling studies confirm the role of acid chlorides as carbon dianion linchpin reagents and have led to a revised reaction mechanism for the aluminum(III)-mediated Dieckmann cyclization of dicarboxylic acids with acid chlorides.
Eto, Kei; Arimura, Yukiko; Mizuguchi, Hiroko; Nishikawa, Masazumi; Noda, Mami; Ishibashi, Hitoshi
2006-11-01
The effects of docosahexaenoic acid (DHA) and other fatty acids on P2X-receptor-mediated inward currents in rat nodose ganglion neurons were studied using the nystatin perforated patch-clamp technique. DHA accelerated the desensitization rate of the ATP-induced current. DHA showed use-dependent inhibition of the peak ATP-induced current. Other polyunsaturated fatty acids, such as arachidonic acid and eicosapentaenoic acid, displayed a similar use-dependent inhibition. The inhibitory effects of saturated fatty acids including palmitic acid and arachidic acid were weaker than those of polyunsaturated fatty acids. The results suggest that fatty acids may modulate the P2X receptor-mediated response when the channel is in the open-state.
Effects of bile acids on human airway epithelial cells: implications for aerodigestive diseases.
Aldhahrani, Adil; Verdon, Bernard; Ward, Chris; Pearson, Jeffery
2017-01-01
Gastro-oesophageal reflux and aspiration have been associated with chronic and end-stage lung disease and with allograft injury following lung transplantation. This raises the possibility that bile acids may cause lung injury by damaging airway epithelium. The aim of this study was to investigate the effect of bile acid challenge using the immortalised human bronchial epithelial cell line (BEAS-2B). The immortalised human bronchial epithelial cell line (BEAS-2B) was cultured. A 48-h challenge evaluated the effect of individual primary and secondary bile acids. Post-challenge concentrations of interleukin (IL)-8, IL-6 and granulocyte-macrophage colony-stimulating factor were measured using commercial ELISA kits. The viability of the BEAS-2B cells was measured using CellTiter-Blue and MTT assays. Lithocholic acid, deoxycholic acid, chenodeoxycholic acid and cholic acid were successfully used to stimulate cultured BEAS-2B cells at different concentrations. A concentration of lithocholic acid above 10 μmol·L -1 causes cell death, whereas deoxycholic acid, chenodeoxycholic acid and cholic acid above 30 μmol·L -1 was required for cell death. Challenge with bile acids at physiological levels also led to a significant increase in the release of IL-8 and IL6 from BEAS-2B. Aspiration of bile acids could potentially cause cell damage, cell death and inflammation in vivo . This is relevant to an integrated gastrointestinal and lung physiological paradigm of chronic lung disease, where reflux and aspiration are described in both chronic lung diseases and allograft injury.
Gim, Sang-A; Sung, Jin-Hee; Shah, Fawad-Ali; Kim, Myeong-Ok
2013-01-01
Ferulic acid, a component of the plants Angelica sinensis (Oliv.) Diels and Ligusticum chuanxiong Hort, exerts a neuroprotective effect by regulating various signaling pathways. This study showed that ferulic acid treatment prevents the injury-induced increase of collapsin response mediator protein 2 (CRMP-2) in focal cerebral ischemia. Glycogen synthase kinase-3β (GSK-3β) regulates CRMP-2 function through phosphorylation of CRMP-2. Moreover, the pro-apoptotic activity of GSK-3β is inactivated by phosphorylation by Akt. This study investigated whether ferulic acid modulates the expression of CRMP-2 and its upstream targets, Akt and GSK-3β, in focal cerebral ischemia. Male rats were treated immediately with ferulic acid (100 mg/kg, i.v.) or vehicle after middle cerebral artery occlusion (MCAO), and then cerebral cortices were collected 24 hr after MCAO. MCAO resulted in decreased levels of phospho-Akt and phospho-GSK-3β, while ferulic acid treatment prevented the decrease in the levels of these proteins. Moreover, phospho-CRMP-2 and CRMP-2 levels increased during MCAO, whereas ferulic acid attenuated these injury-induced increases. These results demonstrate that ferulic acid regulates the Akt/GSK-3β/CRMP-2 signaling pathway in focal cerebral ischemic injury, thereby protecting against brain injury. PMID:23825478
NASA Astrophysics Data System (ADS)
Antonijević-Nikolić, Mirjana; Antić-Stanković, Jelena; Tanasković, Sladjana B.; Korabik, Maria J.; Gojgić-Cvijović, Gordana; Vučković, Gordana
2013-12-01
New cationic Cu(II) complexes with N, N‧, N″, N″‧-tetrakis(2-pyridylmethyl)-1,4,8,11-tetraazacyclotetradecane (tpmc) and aliphatic dicarboxylic acids: pentanedioic (glutaric acid = glutH2), hexanedioic acid (adipic acid = adipH2) and decanedioic acid (sebacic acid = sebH2) of general formula [Cu4(L)(tpmc)2](ClO4)6·xH2O, L = glut, x = 2; L = adip, x = 7; L = seb, x = 6 were isolated. Their composition and charges are proposed based on elemental analyses and molar conductivity measurements. By the comparison of their UV-Vis, reflectance, FTIR and EPR spectral data, CV and SQUID magnetic measurements, with those for the complex with butanedioic acid (succinic acid = succH2) of known molecular structure and analysis of LC/MS spectra, geometry with two [Cu2tpmc]4+ units bridged by dicarboxylate dianion engaging all oxygens is proposed. Within units, Cu(II) ions are also bridged with N portion of cyclam ring. All four complexes were screened to in vitro antimicrobial and cytotoxic activity along with free primary and secondary ligands, Cu(II) salt and solvent controls. Detected antibacterial and cytotoxic activity for the complexes was enhanced in most cases than the corresponding controls.
High temperature dissolution of oxides in complexing media
NASA Astrophysics Data System (ADS)
Sathyaseelan, Valil S.; Rufus, Appadurai L.; Subramanian, Hariharan; Bhaskarapillai, Anupkumar; Wilson, Shiny; Narasimhan, Sevilimedu V.; Velmurugan, Sankaralingam
2011-12-01
Dissolution of transition metal oxides such as magnetite (Fe 3O 4), mixed ferrites (NiFe 2O 4, ZnFe 2O 4, MgFe 2O 4), bonaccordite (Ni 2FeBO 5) and chromium oxide (Cr 2O 3) in organic complexing media was attempted at higher temperatures (80-180 °C). On increasing the temperature from 80 to 180 °C, the dissolution rate of magnetite in nitrilo triacetic acid (NTA) medium increased six folds. The trend obtained for the dissolution of other oxides was ZnFe 2O 4 > NiFe 2O 4 > MgFe 2O 4 > Cr 2O 3, which followed the same trend as the lability of their metal-oxo bonds. Other complexing agents such as ethylene diamine tetra acetic acid (EDTA), pyridine dicarboxylic acid (PDCA), citric acid and reducing agents viz., oxalic acid and ascorbic acid were also evaluated for their oxide dissolution efficiency at 160 °C. EDTA showed maximum dissolution rate of 21.4 μm/h for magnetite. Addition of oxalic acid/ascorbic acid to complexing media (NTA/EDTA) showed identical effect on the dissolution of magnetite. Addition of hydrazine, another reducing agent, to NTA decreased the rate of dissolution of magnetite by 50%.
Differential distribution of amino acids in plants.
Kumar, Vinod; Sharma, Anket; Kaur, Ravdeep; Thukral, Ashwani Kumar; Bhardwaj, Renu; Ahmad, Parvaiz
2017-05-01
Plants are a rich source of amino acids and their individual abundance in plants is of great significance especially in terms of food. Therefore, it is of utmost necessity to create a database of the relative amino acid contents in plants as reported in literature. Since in most of the cases complete analysis of profiles of amino acids in plants was not reported, the units used and the methods applied and the plant parts used were different, amino acid contents were converted into relative units with respect to lysine for statistical analysis. The most abundant amino acids in plants are glutamic acid and aspartic acid. Pearson's correlation analysis among different amino acids showed that there were no negative correlations between the amino acids. Cluster analysis (CA) applied to relative amino acid contents of different families. Alismataceae, Cyperaceae, Capparaceae and Cactaceae families had close proximity with each other on the basis of their relative amino acid contents. First three components of principal component analysis (PCA) explained 79.5% of the total variance. Factor analysis (FA) explained four main underlying factors for amino acid analysis. Factor-1 accounted for 29.4% of the total variance and had maximum loadings on glycine, isoleucine, leucine, threonine and valine. Factor-2 explained 25.8% of the total variance and had maximum loadings on alanine, aspartic acid, serine and tyrosine. 14.2% of the total variance was explained by factor-3 and had maximum loadings on arginine and histidine. Factor-4 accounted 8.3% of the total variance and had maximum loading on the proline amino acid. The relative content of different amino acids presented in this paper is alanine (1.4), arginine (1.8), asparagine (0.7), aspartic acid (2.4), cysteine (0.5), glutamic acid (2.8), glutamine (0.6), glycine (1.0), histidine (0.5), isoleucine (0.9), leucine (1.7), lysine (1.0), methionine (0.4), phenylalanine (0.9), proline (1.1), serine (1.0), threonine (1.0), tryptophan (0.3), tyrosine (0.7) and valine (1.2).
Code of Federal Regulations, 2010 CFR
2010-07-01
...-methylethyl)-5-oxo-1H-imidazol-2-yl]-3-quinoline carboxylic acid; tolerance for residues. 180.426 Section 180...-Dihydro-4-methyl-4-(1-methylethyl)-5-oxo-1H-imidazol-2-yl]-3-quinoline carboxylic acid; tolerance for...)-5-oxo-1H-imidazol-2-yl]-3-quinoline carboxylic acid, in or on the raw agricultural commodity soybean...
NASA Astrophysics Data System (ADS)
Golobostanfard, Mohammad Reza; Abdizadeh, Hossein
2013-03-01
The effects of different acid catalysts of nitric acid, hydrochloric acid, sulfuric acid, phosphoric acid, boric acid, acetic acid, and citric acid on structural, morphological, and optoelectrical properties of nanocrystalline spin-coated TiO2 thin films synthesized via alkoxide sol-gel route were investigated. It was found that only the sols with HNO3 and HCl are suitable for film preparation. The X-ray diffractometry and Raman analysis showed that crystalline phases could be controlled by the type of acid catalyst. Although the H2SO4 sol shows good stability, it causes extremely different morphology to form due to its different sol nature and high contact angle. Fourier transformed infrared spectra confirmed the presence of acid anion species in all samples even after calcination. Furthermore, it was inferred from UV-visable absorption spectra that although the band gap and thickness of the films are independent of acid catalyst type, the refractive index and porosity of the films are strongly affected by the type of acids.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Smith, H.A. Jr.
1962-08-01
I. Methyl 2-methyl-2-thiazoline-4-carboxylate was synthesized and converted to the corresponding acid. The behavior of the carboxythiazoline in various concentrations of mineral acids was studied spectrophotometrically. The cyclization of N-acetylcysteine to form a thiazoline-ring compound in concentrated mineral acids was also studied by this means. N-Acetylcysteine in concentrated mineral acid solutions yielded 2-methyl-2-thiazoline-4-carboxylic acid, which also was obtained by controlied hydrolysis of the corresponding methyl ester. Hydrolysis of methyl 2-methyl2-thiazoline-4-carboxylate, pK 3.05, in 0.1M sodium hydroxide yielded the corresponding carboxythiazoline in solution, pK 2.20 and 4.95. The carboxythiazoline was hydrolyzed very slowly in 7M hydrochloric acid, but the velocity of reactionmore » increased with decreasing acid concentration to a maximum at about pH 1.7; the products were N- and Sacetylcysteine, as well as cysteine and acetic acid. At acid concentrations below 0.2M, the last two products were formed slowly, and a pseudo-equilibrium could be established between thiazolinium ion, N-, and S-acetylcysteine. Equilibrium constants were determined. II. 4,4'-Dithiobis (benzenesulfonic acid) (I) and 4,4'-dithiobis(1-naphthalenesulfonic acid) (II) were synthesized from sulfanilic and naphthionic acids, respectively. The absorption spectra of I and II and of the corresponding mercaptans were determined. The thiol-disuifide interchange reactions were studied by spectrophotometric means for the reactions of cysteine with I and with II, and the equilibrium constants were determined. The systems had spectra very similar to those of the respective mixed disuifides with cysteine, and it was not possible to determine the concentrations from absorbancy measurements. On the other hand, the mercaptide ions had spectra different from the other species, with maxima at 285 and 348 m mu , respectively, and the concentrations of the corresponding mercaptans could be calculated from the absorbancies at these wavelengths. By appropriate choice of the initial concentrations and of pH, the equilibrium concentrations could be made negligible, and the equilibrium constants determined.« less
Gul, Zulfiye; Demircan, Celaleddin; Bagdas, Deniz; Buyukuysal, Rifat Levent
2016-08-01
The effectiveness of chlorogenic acid and its main metabolites, caffeic and quinic acids, against oxidative stress was investigated. Resveratrol, another natural phenolic compound, was also tested for comparison. Rat cortical slices were incubated with 200 μM H2O2 for 1 h, and alterations in oxidative stress parameters, such as 2, 3, 5-triphenyltetrazolium chloride (TTC) staining and the production of both malondialdehyde (MDA) and reactive oxygen species (ROS), were assayed in the absence or presence of phenolic compounds. Additionally, the effectiveness of chlorogenic acid and other compounds on H2O2-induced increases in fluorescence intensities were also compared in slice-free incubation medium. Although quinic acid failed, chlorogenic and caffeic acids significantly ameliorated the H2O2-induced decline in TTC staining intensities. Although resveratrol also caused an increase in staining intensity, its effect was not dose-dependent; the high concentrations of resveratrol tested in the present study (10 and 100 μM) further lessened the staining of the slices. Additionally, all phenolic compounds significantly attenuated the H2O2-induced increases in MDA and ROS levels in cortical slices. When the IC50 values were compared to H2O2-induced alterations, chlorogenic acid was more potent than either its metabolites or resveratrol for all parameters studied under these experimental conditions. In slice-free experimental conditions, on the other hand, chlorogenic and caffeic acids significantly attenuated the fluorescence emission enhanced by H2O2 with a similar order of potency to that obtained in slice-containing physiological medium. These results indicate that chlorogenic acid is a more potent phenolic compound than resveratrol and its main metabolites caffeic and quinic acids against H2O2-induced alterations in oxidative stress parameters in rat cortical slices.
2011-01-01
Background Succinic acid is a building-block chemical which could be used as the precursor of many industrial products. The dissolved CO2 concentration in the fermentation broth could strongly regulate the metabolic flux of carbon and the activity of phosphoenolpyruvate (PEP) carboxykinase, which are the important committed steps for the biosynthesis of succinic acid by Actinobacillus succinogenes. Previous reports showed that succinic acid production could be promoted by regulating the supply of CO2 donor in the fermentation broth. Therefore, the effects of dissolved CO2 concentration and MgCO3 on the fermentation process should be investigated. In this article, we studied the impacts of gaseous CO2 partial pressure, dissolved CO2 concentration, and the addition amount of MgCO3 on succinic acid production by Actinobacillus succinogenes ATCC 55618. We also demonstrated that gaseous CO2 could be removed when MgCO3 was fully supplied. Results An effective CO2 quantitative mathematical model was developed to calculate the dissolved CO2 concentration in the fermentation broth. The highest succinic acid production of 61.92 g/L was obtained at 159.22 mM dissolved CO2 concentration, which was supplied by 40 g/L MgCO3 at the CO2 partial pressure of 101.33 kPa. When MgCO3 was used as the only CO2 donor, a maximal succinic acid production of 56.1 g/L was obtained, which was just decreased by 7.03% compared with that obtained under the supply of gaseous CO2 and MgCO3. Conclusions Besides the high dissolved CO2 concentration, the excessive addition of MgCO3 was beneficial to promote the succinic acid synthesis. This was the first report investigating the replaceable of gaseous CO2 in the fermentation of succinic acid. The results obtained in this study may be useful for reducing the cost of succinic acid fermentation process. PMID:22040346
2. ACID STORAGE SHED, FRONT AND RIGHT SIDES, LOOKING SOUTHWEST. ...
2. ACID STORAGE SHED, FRONT AND RIGHT SIDES, LOOKING SOUTHWEST. - NIKE Missile Base C-84, Acid Storage Shed, North of launch area, northwest of earthen berm of Acid Fueling Station, Barrington, Cook County, IL
Uracil in formic acid hydrolysates of deoxyribonucleic acid
Schein, Arnold H.
1966-01-01
1. When DNA is hydrolysed with formic acid for 30min. at 175° and the hydrolysate is chromatographed on paper with propan-2-ol–2n-hydrochloric acid, in addition to expected ultraviolet-absorbing spots corresponding to guanine, adenine, cytosine and thymine, an ultraviolet-absorbing region with RF similar to that of uracil can be detected. Uracil was separated from this region and identified by its spectra in acid and alkali, and by its RF in several solvent systems. 2. Cytosine, deoxyribocytidine and deoxyribocytidylic acid similarly treated with formic acid all yielded uracil, as did a mixture of deoxyribonucleotides. 3. Approx. 4% of deoxyribonucleotide cytosine was converted into uracil by the formic acid treatment. ImagesFig. 1. PMID:5949371
40 CFR 721.3032 - Boric acid (H3BO2), zinc salt.
Code of Federal Regulations, 2010 CFR
2010-07-01
... 40 Protection of Environment 30 2010-07-01 2010-07-01 false Boric acid (H3BO2), zinc salt. 721... Substances § 721.3032 Boric acid (H3BO2), zinc salt. (a) Chemical substance and significant new uses subject to reporting. (1) The chemical substance identified as boric acid (H3BO2), zinc salt (PMN P-97-553...
40 CFR 721.3032 - Boric acid (H3BO2), zinc salt.
Code of Federal Regulations, 2011 CFR
2011-07-01
... 40 Protection of Environment 31 2011-07-01 2011-07-01 false Boric acid (H3BO2), zinc salt. 721... Substances § 721.3032 Boric acid (H3BO2), zinc salt. (a) Chemical substance and significant new uses subject to reporting. (1) The chemical substance identified as boric acid (H3BO2), zinc salt (PMN P-97-553...
NASA Technical Reports Server (NTRS)
Levi, N.; Lawless, J. G.
1978-01-01
A problem encountered in the analysis of amino acids in chemical evolution experiments and in extracts of meteorites is the large number present. A method for selectively destroying the alpha-amino acids, with only the beta- and gamma-amino acids remaining in the solution, is described. The amino acids used were racemic, with one milliliter of solution containing 0.0000025 mol of each acid irradiated in a 1-cm quartz cell having 254-nm monochromatic light in the presence of CuCl2. Excess H2S was added to precipitate the Cu (2+) as CuS. A gas chromatographic analysis was used to observe that irradiation with 254-nm light in the presence of Cu (2+) destroyed all the amino acids except the beta and the gamma types. It is concluded that with such a procedure, complex mixtures of amino acids can be simplified to make identification by GC mass spectrometry easier.
Oyeyinka, Samson A; Singh, Suren; Amonsou, Eric O
2017-01-01
The physicochemical and mechanical properties of biofilm prepared from bambara starch modified with varying concentrations of stearic acid (0%, 2.5%, 3.5%, 5%, 7%, and 10%) were studied. By scanning electron microscopy, bambara starch films modified with stearic acid (≥3.5%) showed a progressively rough surface compared to those with 2.5% stearic acid and the control. Fourier transform infrared spectroscopy spectra revealed a peak shift of approximately 31 cm -1 , suggesting the promotion of hydrogen bond formation between hydroxyl groups of starch and stearic acid. The addition of 2.5% stearic acid to bambara starch film reduced water vapor permeability by approximately 17%. Bambara starch films modified with higher concentration of stearic acid were more opaque and showed significantly high melting temperatures. However, mechanical properties of starch films were generally negatively affected by stearic acid. Bambara starch film may be modified with 2.5% stearic acid for improved water vapor permeability and thermal stability with minimal effect on tensile strength. © 2016 Institute of Food Technologists®.
DeRuiter, J; Mayfield, C A
1990-11-15
A series of substituted N-[[(4-benzoylamino)phenyl]sulfonyl]amino acids (BAPS-amino acids) were synthesized by established methods, and the stereochemistry of the products was confirmed by HPLC analysis after chiral derivatization. When tested against aldose reductase (alditol:NADP+ oxidoreductase; EC 1.1.1.21; ALR2) isolated from rat lens, all of the BAPS-amino acids were determined to be significantly more inhibitory than the corresponding N-(phenylsulfonyl)amino acids. Structure-inhibition and enzyme kinetic analyses suggest that the BAPS-amino acids inhibit ALR2 by a mechanism similar to the N-(phenylsulfonyl)amino acids. However, multiple inhibition analyses indicate that the increased inhibitory activity of the BAPS-amino acids is a result of interaction with multiple sites present on ALR2. Enzyme specificity studies with several of the BAPS-amino acids demonstrated that these compounds do not produce significant inhibition of other nucleotide-requiring enzymes including aldehyde reductase (alcohol: NADP+ oxidoreductase; EC 1.1.1.2; ALR1).
Ohtani, K; Okai, K; Yamashita, U; Yuasa, I; Misaki, A
1995-03-01
An acidic polysaccharide was isolated from the water-soluble mucilage extracted from dried leaves of Corchorus olitorius, known as Moroheiya in Japan (3.0 g per 100 g). This polysaccharide showed a single peak in a Sepharose CL-6B column, and the specific rotation in H2O at 25 degrees C was +250 degrees. The polysaccharide was rich in uronic acid (65%), and consisted of rhamnose, glucose, galacturonic acid, and glucuronic acid in a molar ratio of 1.0:0.2:0.2:0.9:1.7, in addition to 3.7% of the acetyl group. A methylation analysis, Smith degradation study and fragmentation analysis suggested that this polysaccharide mainly consisted of O-4 substituted galacturonic acid and glucuronic acid, and O-2 substituted rhamnose residues, and that most of the (1-->4)-linked uronic acid residues were substituted at the O-3 position with glucuronic acid residues. This polysaccharide showed proliferative activity toward the murine splenocyte.
Generation and esterification of electrophilic fatty acid nitroalkenes in triacylglycerides
Fazzari, Marco; Khoo, Nicholas; Woodcock, Steven R.; Li, Lihua; Freeman, Bruce A.; Schopfer, Francisco J.
2015-01-01
Electrophilic fatty acid nitroalkenes (NO2-FA) are products of nitric oxide and nitrite-mediated unsaturated fatty acid nitration. These electrophilic products induce pleiotropic signaling actions that modulate metabolic and inflammatory responses in cell and animal models. The metabolism of NO2-FA includes reduction of the vinyl nitro moiety by prostaglandin reductase-1, mitochondrial β–oxidation and Michael addition with low molecular weight nucleophilic amino acids. Complex lipid reactions of fatty acid nitroalkenes are not well defined. Herein we report the detection and characterization of NO2-FA-containing triacylglycerides (NO2-FA-TAG) via mass spectrometry-based methods. In this regard, unsaturated fatty acids of dietary triacylglycerides are targets for nitration reactions during gastric acidification, where NO2-FA-TAG can be detected in rat plasma after oral administration of nitro-oleic acid (NO2-OA). Furthermore, the characterization and profiling of these species, including the generation of beta oxidation and dehydrogenation products, could be detected in NO2-OA supplemented adipocytes. These data revealed that NO2-FA-TAG, formed by either the direct nitration of esterified unsaturated fatty acids or the incorporation of nitrated free fatty acids into triacylglycerides, contribute to the systemic distribution of these reactive electrophilic mediators and may serve as a depot for subsequent mobilization by lipases to in turn impact adipocyte homeostasis and tissue signaling events. PMID:26066303
Controlling Disulfide Bond Formation and Crystal Growth from 2-Mercaptobenzoic Acid
DOE Office of Scientific and Technical Information (OSTI.GOV)
Rowland, Clare E.; Cantos, P. M.; Toby, B. H.
2011-03-02
We report disulfide bond formation from 2-mercaptobenzoic acid (2-MBA) under hydrothermal conditions as a function of pH. Under acidic conditions, 2-MBA remains unchanged. Upon increasing pH, however, we observe 50% oxidation to 2,2'-disulfanediyldibenzoic acid (2,2'-DSBA), which is isolated as a cocrystal of both the thiol and disulfide molecules. At neutral pH, we observe complete oxidation and concurrent crystal growth. The pH sensitivity of this system allows targeting crystals of specific composition from simple building units through a straightforward pH manipulation.
NASA Astrophysics Data System (ADS)
Bikkina, Srinivas; Kawamura, Kimitaka; Imanishi, Katsuya; Boreddy, S. K. R.; Nojiri, Yukihiro
2015-05-01
In order to assess the seasonal variability of atmospheric abundances of dicarboxylic acids, oxocarboxylic acids, and α-dicarbonyls over the North Pacific and Sea of Japan, aerosol samples were collected along the longitudinal transacts during six cruises between Canada and Japan. The back trajectory analyses indicate that aerosol samples collected in winter and spring are influenced by the East Asian outflow, whereas summer and fall samples are associated with the pristine maritime air masses. Molecular distributions of water-soluble organics in winter and spring samples show the predominance of oxalic acid (C2) followed by succinic (C4) and malonic acids (C3). In contrast, summer and fall marine aerosols are characterized by the predominance of C3 over C4. Concentrations of dicarboxylic acids were higher over the Sea of Japan than the North Pacific. With a lack of continental outflow, higher concentrations during early summer are ascribed to atmospheric oxidation of organic precursors associated with high biological activity in the North Pacific. This interpretation is further supported by the high abundances of azelaic acid, which is a photochemical oxidation product of biogenic unsaturated fatty acids, over the Bering Sea in early summer when surface waters are characterized by high biological productivity. We found higher ratios of oxalic acid to pyruvic and glyoxylic acids (C2/Pyr and C2/ωC2) and glyoxal and methylglyoxal (C2/Gly and C2/MeGly) in summer and fall than in winter and spring, suggesting a production of C2 from the aqueous-phase oxidation of oceanic isoprene. In this study, dicarboxylic acids account for 0.7-38% of water-soluble organic carbon.
Jobelius, Carsten; Frimmel, Fritz H; Zwiener, Christian
2014-05-01
The anaerobic microbial degradation of aromatic and heterocyclic compounds is a prevalent process in contaminated groundwater systems. The introduction of functional groups into the contaminant molecules often results in aromatic and heterocyclic and succinic acids. These metabolites can be used as indicators for prevailing degradation processes. Therefore, there is a strong interest in developing analytical methods for screening and identification of these metabolites. In this study, neutral loss scans (NLS) by liquid chromatography-electrospray ionization/tandem mass spectrometry with losses of CO2 (NL ∆m/z = 44) and C2H4(CO2)2 (NL ∆m/z = 116) were applied for the first time successfully to screen selectively for acidic and succinic metabolites of aromatic and heterocyclic contaminants in two fulvic acid fractions from a contaminated site and a downstream region of a tar oil-polluted groundwater. Identification of these preselected signals was performed by high-resolution mass spectrometry with a liquid chromatography-electrospray ionization quadrupole time-of-flight mass spectrometry instrument. High-resolution mass and mass fragmentation data were then compared with a list of known metabolites from a literature search or matched with chemical databases supported with in silico fragmentation. Based on authentic analytical standards, several compounds from NLS were identified (e.g., 4-hydroxy-3-methylbenzoic acid, benzylsuccinic acid, naphthyl-2-methylsuccinic acid, 2-carboxyindane, and 2-carboxybenzothiophene) and tentatively identified (e.g., benzofuranmethylsuccinic acid and dihydrocarboxybenzothiophene) as aromatic, phenolic, heterocyclic, and succinic acids. The acidic metabolites were found exclusively in the contaminated region of the aquifer which indicates active biodegradation processes and no relevant occurrence of acidic metabolites in the downstream region.
Weïwer, Michel; Chen, Chi-Chang; Kemp, Melissa M.; Linhardt, Robert J.
2013-01-01
α-Sialic acid azide 1 has been used as a substrate for the efficient preparation of 1,2,3-triazole derivatives of sialic acid using the copper-catalyzed azide-alkyne Huisgen cycloaddition (“click chemistry”). Our approach is to generate non-natural N-glycosides of sialic acid that are resistant to neuraminidase catalyzed hydrolysis as opposed to the natural O-glycosides. These N-glycosides would act as neuraminidase inhibitors to prevent the release of new virions. As a preliminary study, a small library of 1,2,3-triazole-linked sialic acid derivatives has been synthesized in 71-89% yield. A disaccharide mimic of sialic acid has also been prepared using the α-sialic acid azide 1 and a C-8 propargyl sialic acid acceptor in 68% yield. A model sialic acid coated dendrimer was also synthesized from a per-propargylated pentaerythritol acceptor. These novel sialic acid derivatives were then evaluated as potential neuraminidase inhibitors using a 96-well plate fluorescence assay; micromolar IC50 values were observed, comparable to the known sialidase inhibitor Neu5Ac2en. PMID:24223493
NASA Astrophysics Data System (ADS)
Bikkina, Srinivas; Kawamura, Kimitaka; Miyazaki, Yuzo
2015-05-01
The present study aims to assess the molecular distributions of water-soluble dicarboxylic acids (diacids: C2-C12), oxocarboxylic acids (C2-C9), and α-dicarbonyls (glyoxal and methylglyoxal) in aerosols collected over the western North Pacific (WNP) during a summer cruise (August to September 2008). The measured water-soluble organics show pronounced latitudinal distributions with higher concentrations in the region of 30°N-45°N (average 63 ng m-3) than 10°N-30°N (18 ng m-3). Mass fraction of oxalic acid (C2) in total aliphatic diacids (ΣC2-C12) showed higher values (72 ± 10%) in lower latitude (10°N-30°N) than that (56 ± 16%) in higher latitude (30°N-45°N), suggesting a photochemical production of C2 due to an increased insolation over the tropical WNP. A similar trend was found in other diagnostic ratios such as oxalic to succinic (C2/C4) and oxalic to glyoxylic acid (C2/ωC2), which further corroborate an enhanced photochemical aging over the WNP. In addition, relative abundances of oxalic acid in total diacids showed a marked increase as a function of ambient temperature, supporting their photochemical production. Constantly low concentration ratios of adipic and phthalic acids relative to azelaic acid suggest a small contribution of anthropogenic sources and an importance of oceanic sources during the study period. Significant production of C2 through oxidation of biogenic volatile organic compounds emitted from the sea surface is also noteworthy, as inferred from the strong linear correlations among water-soluble organic carbon, methanesulphonic acid, and oxalic acid. Sea-to-air emission of unsaturated fatty acids also contributes to formation of diacids over the WNP.
Crystal structures of seven molecular salts derived from benzylamine and organic acidic components
NASA Astrophysics Data System (ADS)
Wen, Xianhong; Jin, Xiunan; Lv, Chengcai; Jin, Shouwen; Zheng, Xiuqing; Liu, Bin; Wang, Daqi; Guo, Ming; Xu, Weiqiang
2017-07-01
Cocrystallization of the commonly available organic amine, benzylamine, with a series of organic acids gave a total of seven molecular salts with the compositions: (benzylamine): (p-toluenesulfonic acid) (1) [(HL)+ · (tsa-)], (benzylamine): (o-nitrobenzoic acid) (2) [(HL+) · (onba)-], (benzylamine): (3,4-methylenedioxybenzoic acid) (3) [(HL+) · (mdba-)], (benzylamine): (mandelic acid) (4) [(HL+) · (mda-)], (benzylamine): (5-bromosalicylic acid)2(5) [(HL+) · (bsac-) · (Hbsac)], (benzylamine): (m-phthalic acid) (6) [(HL+) · (Hmpta-)], and (benzylamine)2: (trimesic acid) (7) [(HL+)2 · (Htma2-)]. The seven salts have been characterised by X-ray diffraction technique, IR, and elemental analysis, and the melting points of all the salts were also reported. And their structural and supramolecular aspects are fully analyzed. The result reveals that among the seven investigated crystals the NH2 groups in the benzylamine moieties are protonated when the organic acids are deprotonated, and the crystal packing is interpreted in terms of the strong charge-assisted Nsbnd H⋯O hydrogen bond formation between the ammonium and the deprotonated acidic groups. Except the Nsbnd H⋯O hydrogen bond, the Osbnd H⋯O hydrogen bonds (charge assisted or neutral) were also found at the salts 4-7. Further analysis of the crystal packing of the salts indicated that a different family of additional CHsbnd O/CH2sbnd O, CHsbnd π/CH2sbnd π, Osbnd O, and Osbnd Cπ associations contribute to the stabilization and expansion of the total high-dimensional (2D-3D) framework structures. For the coexistence of the various weak nonbonding interactions these structures adopted homo or hetero supramolecular synthons or both. Some classical supramolecular synthons, such as R42(8), R43(10) and R44(12), usually observed in organic solids of organic acids with amine, were again shown to be involved in constructing most of these hydrogen bonding networks.
Hodgson, David M; Le Strat, Frédéric; Avery, Thomas D; Donohue, Andrew C; Brückl, Tobias
2004-12-10
Levulinic acid-derived 6-diazoheptane-2,5-dione (9) serves as a common precursor in a formal synthesis of frontalin 19, and in syntheses of cis-nemorensic acid 1, 4-hydroxy-cis-nemorensic acid 2, 3-hydroxy-cis-nemorensic acid 3, and nemorensic acid 4. The key step in these syntheses is the Rh(2)(OAc)(4)-catalyzed tandem carbonyl ylide formation-intermolecular 1,3-dipolar cycloadditions of diazodione 9 with formaldehyde, alkynes or allene, which occur with high regioselectivity. Subsequent oxidative cleavage of the ring originally derived from the cyclic carbonyl ylide intermediate provides a straightforward access to polysubstituted tetrahydrofurans, and in particular an efficient entry to the nemorensic acids. Enantioselective cycloadditions with diazodione 9, using chiral rhodium catalysts, gave cycloadducts in up to 51% ee.
AbuGhazaleh, A A; Schingoethe, D J; Hippen, A R; Kalscheur, K F
2003-11-01
The objective of this study was to examine the effect of feeding fish oil (FO) along with fat sources that varied in saturation of 18 carbon fatty acids (high stearic, high oleic, high linoleic, or high linolenic acids) on rumen, plasma, and milk fatty acid profiles. Four primiparous Holstein cows at 85 d in milk (+/- 40) were assigned to 4 x 4 Latin squares with 4-wk periods. Treatment diets were 1) 1% FO plus 2% commercial fat high in stearic acid (HS); 2) 1% FO plus 2% fat from high oleic acid sunflower seeds (HO); 3) 1% FO plus 2% fat from high linoleic acid sunflower seeds (HLO); and 4) 1% FO plus 2% fat from flax seeds (high linolenic; HLN). Diets were formulated to contain 18% crude protein and were composed of 50% (dry basis) concentrate mix, 25% corn silage, 12.5% alfalfa silage, and 12.5% alfalfa hay. Milk production, milk protein percentages and yields, and dry matter intake were similar across diets. Milk fat concentrations and yields were least for HO and HLO diets. The proportion of milk cis-9, trans-11 conjugated linoleic acid (CLA; 0.71, 0.99, 1.71, and 1.12 g/100 g fatty acids, respectively), and vaccenic acid (TVA; 1.85, 2.60, 4.14, and 2.16 g/100 g fatty acids, respectively) were greatest with the HLO diet. The proportions of ruminal cis-9, trans-11 CLA (0.09, 0.16, 0.18, and 0.16 g/100 g fatty acids, respectively) were similar for the HO, HLO, and HLN diets and all were higher than for the HS diet. The proportions of TVA (2.85, 4.36, 8.69, and 4.64 g/100 g fatty acids, respectively) increased with the HO, HLO, and HLN diets compared with the HS diets, and the increase was greatest with the HLO diet. The effects of fat supplements on ruminal TVA concentrations were also reflected in plasma triglycerides, (2.75, 4.64, 8.77, and 5.42 g/100 g fatty acids, respectively); however, there were no differences in the proportion of cis-9, trans-11 CLA (0.06, 0.07, 0.06, and 0.07 g/100 g fatty acids, respectively). This study further supports the significant role for mammary delta-9 desaturase in milk cis-9, trans-11 CLA production.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Timchalk, Chuck
Phenoxyacetic acids including 2,4-dichlorophenoxyacetic acid (2,4-D) and 4-chloro-2-methylphenoxyacetic acid (MCPA) are widely utilized organic acid herbicides that have undergone extensive toxicity and pharmacokinetic analyses. The dog is particularly susceptible to the toxicity of phenoxyacetic acids and related organic acids relative to other species. Active renal clearance mechanisms for organic acids are ubiquitous in mammalian species, and thus a likely mechanism responsible for the increased sensitivity of the dog to these agents is linked to a lower capacity to secrete organic acids from the kidney. Using published data describing the pharmacokinetics of phenoxyacetic and structurally related organic acids in a varietymore » of species including humans, inter-species comparative pharmacokinetics were evaluated using allometic parameter scaling. For both 2,4-D and MCPA the dog plasma half-life (t1/2) and renal clearance (Clr; ml hr-1) rates did not scale as a function of body weight across species; whereas for all other species evaluated, including humans, these pharmacokinetic parameters reasonably scaled. This exceptional response in the dog is clearly illustrated by comparing the plasma t1/2 at comparable doses of 2,4-D and MCPA, across several species. At a dosage of 5 mg/kg, in dogs the plasma t1/2 for 2,4-D and MCPA were {approx}92 - 106 hr and 63 hr, respectively, which is substantially longer than in the rat ({approx}1 and 6 hr, respectively) or in humans (12 and 11 hr, respectively). This longer t1/2, and slower elimination in the dog, results in substantially higher body burdens of these organic acids, at comparable doses, relative to other species. Although these results indicate the important role of renal transport clearance mechanisms as determinants of the clearance and potential toxicity outcomes of phenoxyacetic acid herbicides across several species, other contributing mechanisms such as reabsorption from the renal tubules is highly likely. These findings suggest that for new structurally similar organic acids, a limited comparative species (rat vs. dog) pharmacokinetic analysis early in the toxicology evaluation process may provide important insight into the relevance of the dog. In summary, the substantial difference between the pharmacokinetics of phenoxyacetic acids and related organic acids in dogs relative to other species, including humans, questions the relevance of using dog toxicity data for the extrapolation of human health risk.« less
Novellasdemunt, Laura; Tato, Irantzu; Navarro-Sabate, Aurea; Ruiz-Meana, Marisol; Méndez-Lucas, Andrés; Perales, Jose Carlos; Garcia-Dorado, David; Ventura, Francesc; Bartrons, Ramon; Rosa, Jose Luis
2013-01-01
Reciprocal regulation of metabolism and signaling allows cells to modulate their activity in accordance with their metabolic resources. Thus, amino acids could activate signal transduction pathways that control cell metabolism. To test this hypothesis, we analyzed the effect of amino acids on fructose-2,6-bisphosphate (Fru-2,6-P2) metabolism. We demonstrate that amino acids increase Fru-2,6-P2 concentration in HeLa and in MCF7 human cells. In conjunction with this, 6-phosphofructo-2-kinase activity, glucose uptake, and lactate concentration were increased. These data correlate with the specific phosphorylation of heart 6-phosphofructo-2-kinase/fructose-2,6-biphosphatase (PFKFB2) isoenzyme at Ser-483. This activation was mediated by the PI3K and p38 signaling pathways. Furthermore, Akt inactivation blocked PFKFB2 phosphorylation and Fru-2,6-P2 production, thereby suggesting that the above signaling pathways converge at Akt kinase. In accordance with these results, kinase assays showed that amino acid-activated Akt phosphorylated PFKFB2 at Ser-483 and that knockdown experiments confirmed that the increase in Fru-2,6-P2 concentration induced by amino acids was due to PFKFB2. In addition, similar effects on Fru-2,6-P2 metabolism were observed in freshly isolated rat cardiomyocytes treated with amino acids, which indicates that these effects are not restricted to human cancer cells. In these cardiomyocytes, the glucose consumption and the production of lactate and ATP suggest an increase of glycolytic flux. Taken together, these results demonstrate that amino acids stimulate Fru-2,6-P2 synthesis by Akt-dependent PFKFB2 phosphorylation and activation and show how signaling and metabolism are inextricably linked. PMID:23457334
Biosynthesis of podophyllotoxin in Linum album cell cultures.
Seidel, Véronique; Windhövel, Jörg; Eaton, Graham; Alfermann, A Wilhelm; Arroo, Randolph R J; Medarde, Manuel; Petersen, Maike; Woolley, Jack G
2002-10-01
Cell cultures of Linum album Kotschy ex Boiss. (Linaceae) showing high accumulation of the lignan podophyllotoxin (PTOX) were established. Enzymological studies revealed highest activities of phenylalanine ammonia-lyase, cinnamyl alcohol dehydrogenase, 4-hydroxycinnamate:CoA ligase and cinnamoyl-CoA:NADP oxidoreductase immediately prior to PTOX accumulation. To investigate PTOX biosynthesis, feeding experiments were performed with [2-(13)C]3',4'-dimethoxycinnamic acid, [2-(13)C]3',4'-methylenedioxycinnamic acid (MDCA), [2-(13)C]3',4',5'-trimethoxycinnamic acid, [2-(13)C]sinapic acid, [2-(13)C]- and [2,3-(13)C(2)]ferulic acid. Analysis of the metabolites by HPLC coupled to tandem mass spectrometry revealed incorporation of label from ferulic acid into PTOX and deoxypodophyllotoxin (DOP). In addition, MDCA was also unambiguously incorporated intact into PTOX. These observations suggest that in L. album both ferulic acid and methylenedioxy-substituted cinnamic acid can be incorporated into lignans. Furthermore, it appears that, in this species, the hydroxylation of DOP is a rate-limiting point in the pathway leading to PTOX. Electronic supplementary material to this paper can be obtained by using the Springer LINK server located at http://dx.doi.org/wo.1007/s00425-002-0834-1.
Code of Federal Regulations, 2010 CFR
2010-07-01
... 40 Protection of Environment 23 2010-07-01 2010-07-01 false S-Abscisic Acid, (S)-5-(1-hydroxy-2,6... Exemptions From Tolerances § 180.1281 S-Abscisic Acid, (S)-5-(1-hydroxy-2,6,6-trimethyl-4-oxo-1-cyclohex-2... from the requirement of a tolerance is established for residues of S-Abscisic Acid in or on all food...
[Studies on chemical constituents from rhizome of Anemone flaccida].
Zhang, Lan-tian; Takaishi, Yoshihisa; Zhang, Yan-wen; Duan, Hong-quan
2008-07-01
To study the chemical constituents from Anemone flaccida. Chemical constituents were isolated by repeated column chromatography (silica gel, Toyopearl HW-40C and preparative HPLC). The structures were elucidated on the basis of spectral data analysis. Twelve triterpenes were isolated and their structures were identified as follow: oleanolic acid (1), oleanolic acid 3-O-beta-D-glccopyranosyl-(1-->2)-beta-D-xylopyranoside (2), eleutheroside K (3), oleanolic acid 3-O-alpha-L-rhamnopyranosyl-(1-->2)-beta-D-xylopyranoside (4), oleanolic acid 3-O-beta-D-glccopyranosyl-(1-->2)-alpha-L-arabinofurnoside (5), oleanolic acid 3-O-beta-D-glccuronopyranose (6), oleanolic acid 3-O-beta-D-glccuronopyranose methyl ester (7), oleanolic acid 28-O-alpha-L-rhamnopyranosyl(1-->4)-beta-D-glccopyranosyl (1-->6)-beta-D-glccopyranosyl (8), oleanolic acid 3-O-beta-D-glccuronopyranose 28-O-alpha-L-rhamnopyranosyl (1-->4)-beta-D-glccopyranosyl (1-->6)-beta-D-glccopyranoside (9), oleanolic acid 3-O-beta-D-glccopyranosyl methyl ester 28-O-alpha-L-rhamnopyranosyl (1-->4)-beta-D-glccopyranosyl (1-->6)-beta-D-glccopyranoside (10), oleanolic acid 3-O-beta-D-glccopyranosyl-(1-->2)-beta-D-xylopyranosyl-28-O-alpha-L-rhamnopyranosyl (1-->4)-beta-D-glccopyranosyl (1-->6)-beta-D-glccopyranoside (11), oleanolic acid 3-O-alpha-L-rh-amnopyranosyl-(1-->2)-alpha-L-arabinopyrnosyl-28-O-alpha-L-rhamnopyranosyl (1-->4)-beta-D-glccopyranosyl (1-->6)-beta-D-glccopyranoside (12). compounds 5-8, 10, 12 were isolated from this plant for the first time. Compounds 2, 5 and 11 showed positive anti-tumor activities.
Weeks, Andrea; Boone, Adrienne; Luensmann, Doerte; Jones, Lyndon; Sheardown, Heather
2013-09-01
Conventional and silicone hydrogels as models for contact lenses were prepared to determine the effect of the presence of hyaluronic acid on lysozyme sorption and denaturation. Hyaluronic acid was loaded into poly(2-hydroxyethyl methacrylate) and poly(2-hydroxyethyl methacrylate)/TRIS--methacryloxypropyltris (trimethylsiloxy silane) hydrogels, which served as models for conventional and silicone hydrogel contact lens materials. The hyaluronic acid was cross-linked using 1-ethyl-3-(3-dimethylaminopropyl)-carbodiimide in the presence of dendrimers. Active lysozyme was quantified using a Micrococcus lysodeikticus assay while total lysozyme was determined using 125-I radiolabeled protein. To examine the location of hyaluronic acid in the gels, 6-aminofluorescein labeled hyaluronic acid was incorporated into the gels using 1-ethyl-3-(3-dimethylaminopropyl)-carbodiimide chemistry and the gels were examined using confocal laser scanning microscopy. Hyaluronic acid incorporation significantly reduced lysozyme sorption in poly(2-hydroxyethyl methacrylate) (p < 0.00001) and poly(2-hydroxyethyl methacrylate)/TRIS--methacryloxypropyltris (trimethylsiloxy silane) (p < 0.001) hydrogels, with the modified materials sorbing only 20% and 16% that of the control, respectively. More importantly, hyaluronic acid also decreased lysozyme denaturation in poly(2-hydroxyethyl methacrylate) (p < 0.005) and poly(2-hydroxyethyl methacrylate)/TRIS--methacryloxypropyltris (trimethylsiloxy silane) (p < 0.02) hydrogels. The confocal laser scanning microscopy results showed that the hyaluronic acid distribution was dependent on both the material type and the molecular weight of hyaluronic acid. This study demonstrates that hyaluronic acid incorporated as a wetting agent has the potential to reduce lysozyme sorption and denaturation in contact lens applications. The distribution of hyaluronic acid within hydrogels appears to affect denaturation, with more surface mobile, lower molecular weight hyaluronic acid being more effective in preventing denaturation.
Lajczak, Natalia K; Saint-Criq, Vinciane; O'Dwyer, Aoife M; Perino, Alessia; Adorini, Luciano; Schoonjans, Kristina; Keely, Stephen J
2017-09-01
Bile acids and epithelial-derived human β-defensins (HβDs) are known to be important factors in the regulation of colonic mucosal barrier function and inflammation. We hypothesized that bile acids regulate colonic HβD expression and aimed to test this by investigating the effects of deoxycholic acid (DCA) and ursodeoxycholic acid on the expression and release of HβD1 and HβD2 from colonic epithelial cells and mucosal tissues. DCA (10-150 µM) stimulated the release of both HβD1 and HβD2 from epithelial cell monolayers and human colonic mucosal tissue in vitro In contrast, ursodeoxycholic acid (50-200 µM) inhibited both basal and DCA-induced defensin release. Effects of DCA were mimicked by the Takeda GPCR 5 agonist, INT-777 (50 μM), but not by the farnesoid X receptor agonist, GW4064 (10 μM). INT-777 also stimulated colonic HβD1 and HβD2 release from wild-type, but not Takeda GPCR 5 -/- , mice. DCA stimulated phosphorylation of the p65 subunit of NF-κB, an effect that was attenuated by ursodeoxycholic acid, whereas an NF-κB inhibitor, BMS-345541 (25 μM), inhibited DCA-induced HβD2, but not HβD1, release. We conclude that bile acids can differentially regulate colonic epithelial HβD expression and secretion and discuss the implications of our findings for intestinal health and disease.-Lajczak, N. K., Saint-Criq, V., O'Dwyer, A. M., Perino, A., Adorini, L., Schoonjans, K., Keely, S. J. Bile acids deoxycholic acid and ursodeoxycholic acid differentially regulate human β-defensin-1 and -2 secretion by colonic epithelial cells. © FASEB.
Lever, S Z; Parsons, T L
1999-11-01
meso-2,3-Dimercaptosuccinic acid is a suitable chelating agent for routine pharmacotherapy of lead poisoning in children. Administration of meso-2,3-dimercaptosuccinic acid presumably permits complexation of lead in vivo, allowing excretion through urine or feces. Quantification of the lead is achieved independently from the analysis of meso-2,3-dimercaptosuccinic acid and metabolites from the monobromobimane assay. To date, no direct chemical characterization of the Pb species excreted in urine has been successful. Pharmacokinetic correlation of lead excretion with excretion of meso-2,3-dimercaptosuccinic acid and metabolites has been utilized as an indirect method to draw conclusions regarding the identity of the active chelating agent. In this study, we hypothesized that the Pb-coordinated thiols are not reactive with respect to monobromobimane, and thus, the active chelator contained in the lead complex escapes detection. We performed variations of the assay and found that (1) the fluorescence detector response for the meso-2,3-dimercaptosuccinic acid-monobromobimane adduct was clearly attenuated as a function of added Pb, (2) when meso-2, 3-dimercaptosuccinic acid and monobromobimane were mixed prior to the addition of lead, the lead had no effect on detector response, (3) the addition of dithiothreitol does not affect the ability of Pb to react with meso-2,3-dimercaptosuccinic acid and verifies that oxidation of meso-DMSA had not occurred, and (4) the addition of ethylenediaminetetraacetic acid to the assay reverses the result found in point 1, presumably through trans chelation of the Pb-DMSA complex. Indirect quantification of the Pb-DMSA complexes found in urine might be accomplished through modification of the standard monobromobimane assay for analysis of meso-2,3-dimercaptosuccinic acid.
Lactobacilli Inactivate Chlamydia trachomatis through Lactic Acid but Not H2O2
Gong, Zheng; Luna, Yesmin; Yu, Ping; Fan, Huizhou
2014-01-01
Lactobacillus species dominate the microbiome in the lower genital tract of most reproductive-age women. Producing lactic acid and H2O2, lactobacilli are believed to play an important role in prevention of colonization by and growth of pathogens. However, to date, there have been no reported studies characterizing how lactobacilli interact with Chlamydia trachomatis, a leading sexually transmitted bacterium. In this report, we demonstrate inactivation of C. trachomatis infectivity by culture media conditioned by Lactobacillus crispatus, L. gasseri and L. jensenii, known to be dominating organisms in the human vaginal microbiome. Lactobacillus still cultures produced lactic acid, leading to time- and concentration-dependent killing of C. trachomatis. Neutralization of the acidic media completely reversed chlamydia killing. Addition of lactic acid into Lactobacillus-unconditioned growth medium recapitulated the chlamydiacidal activity of conditioned media. The H2O2 concentrations in the still cultures were found to be comparable to those reported for the cervicovaginal fluid, but insufficient to inactivate chlamydiae. Aeration of Lactobacillus cultures by shaking markedly induced H2O2 production, but strongly inhibited Lactobacillus growth and lactic acid production, and thus severely affected acidification, leading to significantly reduced chlamydiacidal efficiency. These observations indicate lactobacilli inactivate chlamydiae primarily through maintaining acidity in a relatively hypoxic environment in the vaginal lumen with limited H2O2, which is consistent with the notion that women with higher vaginal pH are more prone to sexually transmitted C. trachomatis infection. In addition to lactic acid, formic acid and acetic acid also exhibited potent chlamydiacidal activities. Taken together, our findings imply that lowering the vaginal pH through engineering of the vaginal microbiome and other means will make women less susceptible to C. trachomatis infection. PMID:25215504
Variation in the fatty-acid content in seeds of various black, red, and white currant varieties.
Šavikin, Katarina P; Ðorđević, Boban S; Ristić, Mihailo S; Krivokuća-Ðokić, Dragana; Pljevljakušić, Dejan S; Vulić, Todor
2013-01-01
Currant seeds, a by-product of juice production, are recognized as a valuable source of oil rich in polyunsaturated fatty acids. We have evaluated 28 currant varieties for their oil content and fatty-acid composition. The oil content in the seeds ranged from 18.2-27.7%, and no statistical difference between varieties of different fruit color were recorded. Furthermore, the estimated oil yields in the field production ranged from 26.4-212.4 kg/ha. The GC and GC/MS chemical profiles of the seed oils extracted from all examined varieties were common for currants. Linoleic acid (LA) was the major component, with contents ranging from 32.7-46.9% of total fatty acids, followed by α-linolenic acid (ALA; 2.9-32.0 %), oleic acid (OA; 9.8-19.9%), γ-linolenic acid (GLA; 3.3-18.5%), palmitic acid (PA; 4.4-8.1%), stearidonic acid (SDA; 2.2-4.7%), and stearic acid (SA; 1.2-2.4%). Quantitative differences in the fatty-acid profiles between varieties of different fruit color were observed. Blackcurrant varieties showed significantly higher contents of LA, GLA, and PA than red and white currant varieties, whereas significantly higher amounts of ALA and OL were detected in the red and white varieties. Cluster analysis based on the chemical oil profiles joined the blackcurrants in one group, while most of the red and white cultivars joined in a second group at the same linkage distance. Copyright © 2013 Verlag Helvetica Chimica Acta AG, Zürich.
Chemical constituents of gold-red apple and their α-glucosidase inhibitory activities.
He, Qian-Qian; Yang, Liu; Zhang, Jia-Yu; Ma, Jian-Nan; Ma, Chao-Mei
2014-10-01
Ten compounds were isolated and purified from the peels of gold-red apple (Malus domestica) for the 1st time. The identified compounds are 3β, 20β-dihydroxyursan-28-oic acid (1), 2α-hydroxyoleanolic acid (2), euscaphic acid (3), 3-O-p-coumaroyl tormentic acid (4), ursolic acid (5), 2α-hydroxyursolic acid (6), oleanolic acid (7), betulinic acid (8), linolic acid (9), and α-linolenic acid (10). Their structures were determined by interpreting their nuclear magnetic resonance and mass spectrometry (MS) spectra, and by comparison with literature data. Compound 1 is new, and compound 2 is herein reported for the 1st time for the genus Malus. α-Glucosidase inhibition assay revealed 6 of the triterpenoid isolates as remarkable α-glucosidase inhibitors, with betulinic acid showing the strongest inhibition (IC50 = 15.19 μM). Ultra-performance liquid chromatography-electrospray ionization MS analysis of the fruit peels, pomace, flesh, and juice revealed that the peels and pomace contained high levels of triterpenes, suggesting that wastes from the fruit juice industry could serve as rich sources of bioactive triterpenes. © 2014 Institute of Food Technologists®
Gupta, Poulami; De, Bratati
2017-07-03
A GC-MS based analytical approach was undertaken to understand the metabolomic responses of seedlings of 2 salt sensitive (Sujala and MTU 7029) and 2 tolerant varieties (Bhutnath, and Nonabokra) of indica rice (Oryza sativa L.) to NaCl induced stress. The 4 varieties responded differently to NaCl treatment with respect to the conserved primary metabolites (sugars, polyols, amino acids, organic acids and certain purine derivatives) of the leaf of rice seedlings. However, there were significant differences in salt induced production of chorismic acid derivatives. Serotonin level was increased in both the salt tolerant varieties in response to NaCl induced stress. In both the salt tolerant varieties, increased production of the signaling molecule gentisic acid in response to NaCl treatment was noticed. Salt tolerant varieties also produced increased level of ferulic acid and vanillic acid. In the salt sensitive varieties, cinnamic acid derivatives, 4-hydroxycinnamic acid (in Sujala) and 4-hydroxybenzoic acid (in MTU 7029), were elevated in the leaves. So increased production of the 2 signaling molecules serotonin and gentisic acid may be considered as 2 important biomarker compounds produced in tolerant varieties contributing toward NaCl tolerance.
Zhu, Cui Xia; Hong, Feng
2010-01-01
In order to improve yields and to reduce the cost of oxalate decarboxylase (OxDC, EC 4.1.1.2), the induction of OxDC in the white-rot fungus Trametes versicolor was studied in this work. OxDC was induced by addition of inorganic acids including hydrochloric acid, sulfuric acid, and phosphoric acid to culture media. The results showed that all the acids could enhance OxDC expression. The activity of the acid-induced OxDC rose continuously. All of the OxDC volumetric activities induced by the inorganic acids were higher than 20.0 U/L and were two times higher than that obtained with oxalic acid. OxDC productivity was around 4.0 U*L(-1)*day(-1). The highest specific activity against total protein was 3.2 U/mg protein at day 8 after induction of sulfuric acid, and the specific activity against mycelial dry weight was 10.6 U/g at day 9 after induction of hydrochloric acid. The growth of mycelia was inhibited slightly when the pH values in culture media was around 2.5-3.0, while the growth was inhibited heavily when the pH was lower than 2.5.
Lanzini, A; De Tavonatti, M G; Panarotto, B; Scalia, S; Mora, A; Benini, F; Baisini, O; Lanzarotto, F
2003-09-01
Whether ileal absorption of bile acid is up or downregulated in chronic cholestasis is still debated, and most evidence has come from animal studies. To compare ileal bile acid absorption in patients with primary biliary cirrhosis (PBC) and in healthy control subjects, and to assess the effect of ursodeoxycholic acid (UDCA). We studied 14 PBC patients before and during (n=11) UDCA administration, 14 healthy control subjects, and 14 Crohn's disease patients (as disease controls). We used cholescintigraphy to measure retention in the enterohepatic circulation over five successive days of the bile acid analogue (75)Se-homocholic acid-taurine ((75)SeHCAT) as an index of ileal bile acid absorption. Results were expressed as (75)SeHCAT fractional turnover rate (FTR) and t(1/2)12. (75)SeHCAT FTR was 0.19 (0.11)/day, 0.34 (0.11)/day (p<0.001), and 0.83 (0.32)/day in PBC patients, healthy controls (p<0.0001), and Crohn's patients (p<0.001), respectively, which increased to 0.36 (0.16)/day in PBC patients during UDCA treatment (p<0.005). (75)SeHCAT t(1/2)12 was 4.8 (2.1) days in PBC patients, 2.2 (0.5) days (p<0.001) in healthy controls, and 1.0 (0.5) days (p<0.001) in Crohn's disease patients. (75)SeHCAT t(1/2)12 decreased to 2.2 (0.93) days (p< 0.001) in PBC patients during UDCA treatment. Our results support the concept that ileal bile acid absorption is upregulated in PBC patients, and that this effect may contribute towards damaging the cholestatic liver. This upregulation of bile acid absorption is abolished by UDCA.
Hvozdiak, R I; Dankevych, L A; Votselko, S K; Holubets', O V
2005-01-01
Fatty acid composition of cellular lipids of 23 Pseudomonas lupini strains (Beltjukova et Koroljova 1968) has been investigated. Cellular fatty acids which contained from C10 to C19 carbon atoms have been identified. Basic fatty acid of those Pseudomonas cells are hexadecanoic, hexadecenoic and octadecanoic acids. The 3-hydroxydecanoic (C10:0 3OH), 3-hydroxydodecanoic (C12:0 3OH), 2-hydroxydodecanoic (C12:0 2OH) and cyclopropane fatty acids which contain 17 and 19 carbon atoms have been detected in cellular lipids. The cellular fatty acids spectra of 22 P. lupini strains are similar to cellular fatty acids spectrum of the type strain Pseudomonas syringae pv. syringae 8511. Pathogenic isolate 2, which fatty acid content of cell lipids significantly differ from lipids of cell fatty acids from P. lupini strains and cell lipids of fatty acids of typical strains Pseudomonas syringae pv. syringae 8511 and Pseudomonas savastanoi pv. phaseolicola 9066 is the exception.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Struck, W.A.; Elving, P.J.
Alloxan is the dominant product of the chemical oxidation of uric acid under strongly acid conditions; allantoin is the corresponding product for less acidic to alkaline conditions; separate reaction paths have generally been postulated to account for this difference. A study of the electrolytic oxidation of uric acid indicates the presence of a common path which eventually diverges to produce both alloxan and allantoin in comparable amounts, Uric acid gives a well- defined anodic voltammetric wave at a graphite electrode. When uric acid is electrolytically oxidized in diIute acetic acid at large graphite electrodes, 2.2 Faradays are passed, and 0,25more » mole CO/sub 2/, 0.25 mole of a precursor of allantoin, 0.75 mole urea, 0,3 mole parabanic acid and 0.3 mole alloxan simultaneously appear per mole of uric acid oxidized. At any stage during electrolysis, the sum of the moles of allantoin precursor and urea equals the moles of uric acid oxidized. This material balance and the stability of the allantoin precursor indicate that the production of urea is associated with the pathway(s) that produce alloxan and parabanic acid. These and other facts indicate a mechanism whereby uric acid is oxidized in a 2e process to a primary short-lived intermediate, which undergoes three simultaneous transformations: (1) hydrolysis to the allantoin precursor, (2) hydrolysis to alloxan and urea, and (3) further oxidation and hydrolysis leading to parabanic acid and urea. The non- stoichiometric amount of CO/sub 2/ produced and the non-integral number of electrons involved are accounted for by the formation of parabanic acid. The primary oxidation intermediate ultimately produces both allantoin and alloxan, suggesting that this intermediate may be common to all uric acid oxidations and that the ultimate product heretofore considered to be typified by either allantoin or alloxan (but not both) is most likely controlled by experimental conditions. (auth)« less
Soraphen A, an inhibitor of acetyl CoA carboxylase activity, interferes with fatty acid elongation
Jump, Donald B.; Torres-Gonzalez, Moises; Olson, L. Karl
2010-01-01
Acetyl CoA carboxylase (ACC1 & ACC2) generates malonyl CoA, a substrate for de novo lipogenesis (DNL) and an inhibitor of mitochondrial fatty acid β-oxidation (FAO). Malonyl CoA is also a substrate for microsomal fatty acid elongation, an important pathway for saturated (SFA), mono- (MUFA) and polyunsaturated fatty acid (PUFA) synthesis. Despite the interest in ACC as a target for obesity and cancer therapy, little attention has been given to the role ACC plays in long chain fatty acid synthesis. This report examines the effect of pharmacological inhibition of ACC on DNL & palmitate (16:0) and linoleate (18:2,n-6) metabolism in HepG2 and LnCap cells. The ACC inhibitor, soraphen A, lowers cellular malonyl CoA, attenuates DNL and the formation of fatty acid elongation products derived from exogenous fatty acids, i.e., 16:0 & 18:2,n-6; IC50 ~ 5 nM. Elevated expression of fatty acid elongases (Elovl5, Elovl6) or desaturases (FADS1, FADS2) failed to override the soraphen A effect on SFA, MUFA or PUFA synthesis. Inhibition of fatty acid elongation leads to the accumulation of 16- and 18-carbon unsaturated fatty acids derived from 16:0 and 18:2,n-6, respectively. Pharmacological inhibition of ACC activity will not only attenuate DNL and induce FAO, but will also attenuate the synthesis of very long chain saturated, mono- and polyunsaturated fatty acids. PMID:21184748
NASA Astrophysics Data System (ADS)
Ding, Aihua; Jin, Shouwen; Jin, Shide; Hu, KaiKai; Lin, Zhihao; Liu, Hui; Wang, Daqi
2018-01-01
Cocrystallization of the bis(imidazole)/bis(benzimidazole) with a series of organic acids gave a total of eight molecular adducts with the compositions: (3,6-bis(imidazole-1-yl)pyridazine): (trichloroacetic acid)2(1) [(H2L1)2+ · (tca-)2, L1 = 3,6-bis(imidazole-1-yl)pyridazine, tca- = trichloroacetate], (bis(N-imidazolyl)methane): (suberic acid) (2) [(L2) · (H2suba), L2 = bis(N-imidazolyl)methane, H2suba = suberic acid], bis(N-imidazolyl)methane: (3-nitrophthalic acid): 3H2O (3) [(H2L2)2+ · (3-Hnpa-)2 · 3H2O, 3-Hnpa- = 3-nitro hydrogenphthalate], (bis(N-imidazolyl)butane)0.5: (4-nitrophthalic acid): H2O (4) [(H2L3)0.5+ · (4-Hnpa-)- · H2O, L3 = bis(N-imidazolyl)butane, 4-Hnpa- = 4-nitro hydrogenphthalate], (1-(3-(1H-benzimidazol-1-yl)propyl)-1H-benzimidazole): (3,5-dinitrosalicylic acid) (5) [(HL4) · (3,5-dns-), L4 = 1-(3-(1H-benzimidazol-1-yl)propyl)-1H-benzimidazole, 3,5-dns- = 3,5-dinitrosalicylate], (1-(3-(1H-benzimidazol-1-yl)propyl)-1H-benzimidazole): (3-nitrophthalic acid) (6) [(H2L4) · (3-npa2-), L4 = 1-(3-(1H-benzimidazol-1-yl)propyl)-1H-benzimidazole, 3-npa2-=3-nitrogenphthalate], (bis(N-imidazolyl)butane): (pamoic acid) (7) [(H2L3) · (pam), pam = pamoate], and (3,6-bis(imidazole-1-yl)pyridazine): (1,5-naphthalenedisulfonic acid) [(H2L1)2+ · (npda)2- = 1,5-naphthalenedisulfonate] (8). The eight adducts have been characterized by X-ray diffraction technique, infrared spectrum, and elemental analysis, and the melting points of all adducts were also reported. And their structural and supramolecular aspects are fully analyzed. The result reveals that among the eight investigated crystals both the end ring N in the bis(imidazole) moieties are protonated when the organic acids are deprotonated except 2, and 5, and the crystal packing is interpreted in terms of the strong ionic Nsbnd H⋯O H-bond between the imidazolium and the deprotonated acidic groups. Except the Nsbnd H⋯O H-bond, the Osbnd H⋯O H-bonds were also found at the salts 3, 4, 5, and 7, salt 5 has the additional Nsbnd H⋯N H-bond, the Nsbnd H⋯S H-bond was established at 8. Further analysis of the crystal packing of the adducts indicated that a different set of additional CHsbnd O/CH2sbnd O, CHsbnd Cl, CH-π/CH2-π, Clsbnd C, Clsbnd N, Osbnd O, O-π, OH-π, and π-π associations contribute to the stabilization and expansion of the total 3D frameworks. For the coexistence of the various weak interactions these structures had homo or hetero supramolecular synthons or both. Some supramolecular synthons, such as R12(4), R22(7), and R22(8) usually found in crystals of organic acids with imidazole unit, were again shown to be appeared in constructing most of these H-bond networks.
Nisar, Madiha; Wong, Lawrence W Y; Sung, Herman H Y; Haynes, Richard K; Williams, Ian D
2018-06-01
The stoichiometry, X-ray structures and stability of four pharmaceutical cocrystals previously identified from liquid-assisted grinding (LAG) of 11-azaartemisinin (11-Aza; systematic name: 1,5,9-trimethyl-14,15,16-trioxa-11-azatetracyclo[10.3.1.0 4,13 .0 8,13 ]hexadecan-10-one) with trans-cinnamic (Cin), maleic (Mal) and fumaric (Fum) acids are herein reported. trans-Cinnamic acid, a mono acid, forms 1:1 cocrystal 11-Aza:Cin (1, C 15 H 23 NO 4 ·C 9 H 8 O 2 ). Maleic acid forms both 1:1 cocrystal 11-Aza:Mal (2, C 15 H 23 NO 4 ·C 4 H 4 O 4 ), in which one COOH group is involved in self-catenation, and 2:1 cocrystal 11-Aza 2 :Mal (3, 2C 15 H 23 NO 4 ·C 4 H 4 O 4 ). Its isomer, fumaric acid, only affords 2:1 cocrystal 11-Aza 2 :Fum (4). All cocrystal formation appears driven by acid-lactam R 2 2 (8) heterosynthons with short O-H...O=C hydrogen bonds [O...O = 2.56 (2) Å], augmented by weaker C=O...H-N contacts. Despite a better packing efficiency, cocrystal 3 is metastable with respect to 2, probably due to a higher conformational energy for the maleic acid molecule in its structure. In each case, the microcrystalline powders from LAG were useful in providing seeding for the single-crystal growth.
Dachineni, Rakesh; Ai, Guoqiang; Kumar, D. Ramesh; Sadhu, Satya S.; Tummala, Hemachand; Bhat, G. Jayarama
2015-01-01
Data emerging from the past 10 years have consolidated the rationale for investigating the use of aspirin as a chemopreventive agent; however, the mechanisms leading to its anti-cancer effects are still being elucidated. We hypothesized that aspirin’s chemopreventive actions may involve cell cycle regulation through modulation of the levels or activity of cyclin A2/cyclin dependent kinase-2 (CDK2). In this study, HT-29 and other diverse panel of cancer cells were used to demonstrate that both aspirin and its primary metabolite, salicylic acid, decreased cyclin A2 (CCNA2) and CDK2 protein and mRNA levels. The down regulatory effect of either drugs on cyclin A2 levels was prevented by pretreatment with lactacystin, an inhibitor of proteasomes, suggesting the involvement of 26S proteasomes. In-vitro kinase assays showed that lysates from cells treated with salicylic acid had lower levels of CDK2 activity. Importantly, three independent experiments revealed that salicylic acid directly binds to CDK2. Firstly, inclusion of salicylic acid in naïve cell lysates, or in recombinant CDK2 preparations, increased the ability of the anti-CDK2 antibody to immunoprecipitate CDK2, suggesting that salicylic acid may directly bind and alter its conformation. Secondly, in 8-anilino-1-naphthalene-sulfonate (ANS)-CDK2 fluorescence assays, pre-incubation of CDK2 with salicylic acid, dose-dependently quenched the fluorescence due to ANS. Thirdly, computational analysis using molecular docking studies identified Asp145 and Lys33 as the potential sites of salicylic acid interactions with CDK2. These results demonstrate that aspirin and salicylic acid down-regulate cyclin A2/CDK2 proteins in multiple cancer cell lines, suggesting a novel target and mechanism of action in chemoprevention. Implications Biochemical and structural studies indicate that the anti-proliferative actions of aspirin are mediated through cyclin A2/CDK2. PMID:26685215
Oboh, Ganiyu; Agunloye, Odunayo M; Adefegha, Stephen A; Akinyemi, Ayodele J; Ademiluyi, Adedayo O
2015-03-01
Chlorogenic acid is a major phenolic compound that forms a substantial part of plant foods and is an ester of caffeic acid and quinic acid. However, the effect of the structures of both chlorogenic and caffeic acids on their antioxidant and antidiabetic potentials have not been fully understood. Thus, this study sought to investigate and compare the interaction of caffeic acid and chlorogenic acid with α-amylase and α-glucosidase (key enzymes linked to type 2 diabetes) activities in vitro. The inhibitory effect of the phenolic acids on α-amylase and α-glucosidase activities was evaluated. Thereafter, their antioxidant activities as typified by their 1,1-diphenyl-2 picrylhydrazyl radical scavenging ability and ferric reducing antioxidant properties were determined. The results revealed that both phenolic acids inhibited α-amylase and α-glucosidase activities in a dose-dependent manner (2-8 μg/mL). However, caffeic acid had a significantly (p<0.05) higher inhibitory effect on α-amylase [IC50 (concentration of sample causing 50% enzyme inhibition)=3.68 μg/mL] and α-glucosidase (IC50=4.98 μg/mL) activities than chlorogenic acid (α-amylase IC50=9.10 μg/mL and α-glucosidase IC50=9.24 μg/mL). Furthermore, both phenolic acids exhibited high antioxidant properties, with caffeic acid showing higher effects. The esterification of caffeic acid with quinic acid, producing chlorogenic acid, reduces their ability to inhibit α-amylase and α-glucosidase activities. Thus, the inhibition of α-amylase and α-glucosidase activities by the phenolic acids could be part of the possible mechanism by which the phenolic acids exert their antidiabetic effects.
Dziedzic, Krzysztof; Górecka, Danuta; Szwengiel, Artur; Sulewska, Hanna; Kreft, Ivan; Gujska, Elżbieta; Walkowiak, Jarosław
2018-03-01
In this report, we presented the profile of polyphenolic substances in flowers, leaves, stalk and roots of Fagopyrum tataricum estimated by using RP-UHPLC-ESI-MS equipment (reversed-phase ultra-high-performance liquid chromatography electrospray ionisation mass spectrometry). The neutral detergent fibre, acid detergent fibre, acid detergent lignin, cellulose and hemicellulose were also determined. Flowers, leaves, stalk and roots showed varying levels of dietary fibre and polyphenols. The highest content of neutral and acid detergent fibre were found in the roots (63.92 and 45.45% d.m., respectively) while the most rich in phenolic compounds were flowers (4.8 mg/1 g d.m.). Root and stalk contained the highest level of cellulose, 38.70 and 25.57% d.m., respectively. Among the investigated polyphenolic substances such as: 2,6-dihydroxybenzoic acid, 3,4-dihydroxybenzoic acid, 3,5-dihydroxybenzoic acid, 4-hydrobenzoic acid, caffeic acid, catechin, chlorogenic acid, fagopyrin, ferulic acid, myricetin, gallic acid, isovanilic acid, isovitexin, kaempferol, luteolin, p-coumaric acid, procyanidin B2, quercetin, quercetin 3-D galactoside, rutin, syringic acid and vitexin, we observed that the contents of rutin and chlorogenic acid were the highest. We found some correlation between dietary fibre fractions and individual phenolic substances. The levels of acid detergent fibre (ADF), cellulose and hemicellulose were negatively correlated with isovitexin, kaempferol, vitexin, fagopyrin, caffeic acid and procyanidin B2 content. In this investigation, two solvents (water and methanol) were estimated regarding their extraction efficiency of phenolic compounds. Taking these results into consideration, we recommend using methanol as the extractor to isolate chlorogenic acid, fagopyrin, kaempferol, procyanidin B2, quercetin, quercetin 3-D-galactoside, rutin, vitexin, and water for other investigated polyphenolic substances obtained from Fagopyrum tataricum.
Synthesis and characterization of bifunctional surfaces with tunable functional group pairs
NASA Astrophysics Data System (ADS)
Galloway, John M.; Kung, Mayfair; Kung, Harold H.
2016-06-01
Grafting of pairs of functional groups onto a silica surface was demonstrated by tethering both terminals of an organochlorosilane precursor molecule, Cl2(CH3)Si(CH2)4(CO)(OSi(i-Pr)2)(CH2)2Si(CH3)Cl2, that possess a cleavable silyl ester bond, onto a silica surface. Hydrolytic cleavage of the silyl ester bond of the grafted molecule resulted in the generation of organized pairs of carboxylic acid and organosilanol groups. This organosilanol moiety was easily transformed into other functional groups through condensation reactions to form, together with the neighboring acid group, pairs such as carboxylic acid/secondary amine, carboxylic acid/pyridine, and carboxylic acid/phosphine. In the case of carboxylic acid/amine pairing, there was evidence of the formation of amide. A sample grafted with amine-carboxylic acid pairs was three times more active (per free amine) than a sample without such pairs for the nitroaldol condensation of 4-nitrobenzaldehyde and nitromethane.
Incorporation of Oxygen into Abscisic Acid and Phaseic Acid from Molecular Oxygen 1
Creelman, Robert A.; Zeevaart, Jan A. D.
1984-01-01
Abscisic acid accumulates in detached, wilted leaves of Xanthium strumarium. When these leaves are subsequently rehydrated, phaseic acid, a catabolite of abscisic acid, accumulates. Analysis by gas chromatography-mass spectrometry of phaseic acid isolated from stressed and subsequently rehydrated leaves placed in an atmosphere containing 20% 18O2 and 80% N2 indicates that one atom of 18O is incorporated in the 6′-hydroxymethyl group of phaseic acid. This suggests that the enzyme that converts abscisic acid to phaseic acid is an oxygenase. Analysis by gas chromatography-mass spectrometry of abscisic acid isolated from stressed leaves kept in an atmosphere containing 18O2 indicates that one atom of 18O is present in the carboxyl group of abscisic acid. Thus, when abscisic acid accumulates in water-stressed leaves, only one of the four oxygens present in the abscisic acid molecule is derived from molecular oxygen. This suggests that either (a) the oxygen present in the 1′-, 4′-, and one of the two oxygens at the 1-position of abscisic acid arise from water, or (b) there exists a stored precursor with oxygen atoms already present in the 1′- and 4′-positions of abscisic acid which is converted to abscisic acid under conditions of water stress. PMID:16663564
Incorporation of oxygen into abscisic Acid and phaseic Acid from molecular oxygen.
Creelman, R A; Zeevaart, J A
1984-05-01
Abscisic acid accumulates in detached, wilted leaves of Xanthium strumarium. When these leaves are subsequently rehydrated, phaseic acid, a catabolite of abscisic acid, accumulates. Analysis by gas chromatography-mass spectrometry of phaseic acid isolated from stressed and subsequently rehydrated leaves placed in an atmosphere containing 20% (18)O(2) and 80% N(2) indicates that one atom of (18)O is incorporated in the 6'-hydroxymethyl group of phaseic acid. This suggests that the enzyme that converts abscisic acid to phaseic acid is an oxygenase.Analysis by gas chromatography-mass spectrometry of abscisic acid isolated from stressed leaves kept in an atmosphere containing (18)O(2) indicates that one atom of (18)O is present in the carboxyl group of abscisic acid. Thus, when abscisic acid accumulates in water-stressed leaves, only one of the four oxygens present in the abscisic acid molecule is derived from molecular oxygen. This suggests that either (a) the oxygen present in the 1'-, 4'-, and one of the two oxygens at the 1-position of abscisic acid arise from water, or (b) there exists a stored precursor with oxygen atoms already present in the 1'- and 4'-positions of abscisic acid which is converted to abscisic acid under conditions of water stress.
Hydrothermal catalytic deoxygenation of palmitic acid over nickel catalyst
DOE Office of Scientific and Technical Information (OSTI.GOV)
Miao, Chao; Marin-Flores, Oscar; Davidson, Stephen D.
2016-02-01
Fatty acid has recently received considerable interest as a possible precursor for producing renewable hydrocarbon. In this study, we investigated hydrothermal catalytic deoxygenation of palmitic acid to produce paraffin over a Ni/ZrO2 catalyst with no or low-pressure (100 psi) external supply of H2. The results show that the presence of water greatly improved conversion of palmitic acid and paraffin yield. Significant improvement was attributed to the formation of in-situ H2. Without an external H2 supply, a 64.2 C% conversion of palmitic acid was achieved in the presence of water, while only a 17.2 C% conversion was achieved without water. Themore » results also show that the presence of water suppressed the side reactions of palmitic acid, specifically ketonization and esterification. We concluded that, compared with decarboxylation and hydrodeoxygenation, decarbonylation was the major route for palmitic acid deoxygenation catalyzed by Ni/ZrO2. Varieties of shorter-chain paraffin (C8–C14) were formed through hydrogenolysis, which also produced a considerable amount of CH4. A viable reaction pathway for hydrothermal catalytic deoxygenation of palmitic acid in the presence of Ni/ZrO2 was suggested. The results show that hydrogenolysis and decarbonylation were the major reactions that occurred. This study demonstrates that this hydrothermal catalytic process is a promising approach for producing liquid paraffin (C8–C15) from fatty acids under no or low-pressure H2.« less
Parker, R A; Kariya, T; Grisar, J M; Petrow, V
1977-06-01
5-(Tetradecyloxy)-2-furancarboxylic acid (91, RMI 14514) was found to lower blood lipids and to inhibit fatty acid synthesis with minimal effects on liver weight and liver fat content. This fatty acid-like compound represents a new class of hypolipidemic agent; it is effective in rats and monkeys. The compound resulted from discovery of hypolipidemic activity in certain beta-keto esters, postulation and confirmation of the corresponding benzoic acids as active metabolites, and systematic exploration of the structure--activity relationships.
Arimboor, Ranjith; Kumar, K Sarin; Arumughan, C
2008-05-12
A RP-HPLC-DAD method was developed and validated for the simultaneous analysis of nine phenolic acids including gallic acid, protocatechuic acid, p-hydroxybenzoic acid, vanillic acid, salicylic acid, p-coumaric acid, cinnamic acid, caffiec acid and ferulic acid in sea buckthorn (SB) (Hippophaë rhamnoides) berries and leaves. The method was validated in terms of linearity, LOD, precision, accuracy and recovery and found to be satisfactory. Phenolic acid derivatives in anatomical parts of SB berries and leaves were separated into free phenolic acids, phenolic acids bound as esters and phenolic acids bound as glycosides and profiled in HPLC. Berry pulp contained a total of 1068 mg/kg phenolic acids, of which 58.8% was derived from phenolic glycosides. Free phenolic acids and phenolic acid esters constituted 20.0% and 21.2%, respectively, of total phenolic acids in SB berry pulp. The total phenolic acid content in seed kernel (5741 mg/kg) was higher than that in berry pulp and seed coat (Table 2). Phenolic acids liberated from soluble esters constituted the major fraction of phenolic acids (57.3% of total phenolic acids) in seed kernel. 8.4% and 34.3% of total phenolic acids in seed kernel were, respectively contributed by free and phenolic acids liberated from glycosidic bonds. The total soluble phenolic acids content in seed coat (448 mg/kg) was lower than that in seed kernel and pulp (Table 2). Proportion of free phenolic acids in total phenolic acids in seed coat was higher than that in seed kernel and pulp. Phenolic acids bound as esters and glycosides, respectively contributed 49.1% and 20.3% of total phenolic acids in seed coat. The major fraction (approximately 70%) of phenolic acids in SB berries was found to be concentrated in the seeds. Gallic acid was the predominant phenolic acid both in free and bound forms in SB berry parts and leaves.
A new coruleoellagic acid derivative from stems of Rhodamnia dumetorum.
Lakornwong, Waranya; Kanokmedhakul, Kwanjai; Kanokmedhakul, Somdej
2018-07-01
A new coruleoellagic acid derivative, 3,3',4,4',5'-pentamethylcoruleoellagic acid (1) together with nine known compounds, hexamethylcoruleoellagic acid (2), 3,4,3'-tri-O-methylellagic acid (3), heptaphylline (4), 7-methoxymukonal (5), dentatin (6), sinapaldehyde (7), gallic acid (8), 2,6-dimethoxy-4H-pyran-4-one (9) and β-sitosterol (10) were isolated from the stems of Rhodamnia dumetorum. Their structures were identified by physical and spectroscopic data (IR, 1D and 2D NMR, and MS). Compounds 1, 2 and 7-10 were tested for antibacterial activity against six pathogenic bacterial strains (Bacillus cereus, Escherichia coli, Pseudomonas aeruginosa, Salmonella enterica serovar Typhimurium, Staphylococcus aureus, and Methicillin resistant S. aureus (MRSA)).
Analysis of amino acids in nectar from pitchers of Sarracenia purpurea (Sarraceniaceae).
Dress, W; Newell, S; Nastase, A; Ford, J
1997-12-01
Sarracenia purpurea L. (northern pitcher plant) is an insectivorous plant with extrafloral nectar that attracts insects to a water-filled pitfall trap. We identified and quantified the amino acids in extrafloral nectar produced by pitchers of S. purpurea. Nectar samples were collected from 32 pitchers using a wick-sampling technique. Samples were analyzed for amino acids with reverse-phase high-performance liquid chromatography with phenylisothiocyanate derivatization. Detectable amounts of amino acids were found in each of the 32 nectar samples tested. Mean number of amino acids in a nectar sample was 9 (SD = 2.2). No amino acid was detected in all 32 samples. Mean amount of amino acids in a nectar sample (i.e., amount per wick) was 351.4 ng (SD = 113.2). Nine amino acids occurred in 20 of the 32 samples (aspartic acid, cysteine, glutamic acid, glycine, histidine, hydroxyproline, methionine, serine, valine) averaging 263.4 ng (SD = 94.9), and accounting for ~75% of the total amino acid content. Nectar production may constitute a significant cost of carnivory since the nectar contains amino acids. However, some insects prefer nectar with amino acids and presence of amino acids may increase visitation and capture of insect prey.
Maruyama, Hiroko; Kawakami, Fumitaka; Lwin, Thet-Thet; Imai, Motoki; Shamsa, Fazel
2018-01-01
In this study, we examined the inhibitory effects of ferulic acid and caffeic acid on melanin production using a murine B16 melanoma cell line. The mechanisms by which the two acids inhibit melanin production were investigated by evaluating their effects on the activity of tyrosinase, which is involved is the first step of melanin biosynthesis. Ferulic acid showed no toxicity against the melanoma cells at any dose, whereas caffeic acid exerted cellular toxicity at concentrations higher than 0.35 mM. Both ferulic and caffeic acids effectively inhibited melanin production in the B16 melanoma cells. Ferulic acid reduced tyrosinase activity by directly binding to the enzyme, whereas no binding was observed between caffeic acid and tyrosinase. Both ferulic acid and caffeic acid inhibited casein kinase 2 (CK2)-induced phosphorylation of tyrosinase in a dose-dependent manner in vitro. Ferulic acid was found to be a more effective inhibitor of melanin production than caffeic acid; this difference in the inhibitory efficacy between the two substances could be attributable to the difference in their tyrosine-binding activity. Our analysis revealed that both substances also inhibited the CK2-mediated phosphorylation of tyrosinase.
The role of microbial amino acid metabolism in host metabolism.
Neis, Evelien P J G; Dejong, Cornelis H C; Rensen, Sander S
2015-04-16
Disruptions in gut microbiota composition and function are increasingly implicated in the pathogenesis of obesity, insulin resistance, and type 2 diabetes mellitus. The functional output of the gut microbiota, including short-chain fatty acids and amino acids, are thought to be important modulators underlying the development of these disorders. Gut bacteria can alter the bioavailability of amino acids by utilization of several amino acids originating from both alimentary and endogenous proteins. In turn, gut bacteria also provide amino acids to the host. This could have significant implications in the context of insulin resistance and type 2 diabetes mellitus, conditions associated with elevated systemic concentrations of certain amino acids, in particular the aromatic and branched-chain amino acids. Moreover, several amino acids released by gut bacteria can serve as precursors for the synthesis of short-chain fatty acids, which also play a role in the development of obesity. In this review, we aim to compile the available evidence on the contribution of microbial amino acids to host amino acid homeostasis, and to assess the role of the gut microbiota as a determinant of amino acid and short-chain fatty acid perturbations in human obesity and type 2 diabetes mellitus.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Seol, Yongkoo; Javandel, Iraj
Fenton's reagent, a solution of hydrogen peroxide and ferrous iron catalyst, is used for an in-situ chemical oxidation of organic contaminants. Sulfuric acid is commonly used to create an acidic condition needed for catalytic oxidation. Fenton's reaction often involves pressure buildup and precipitation of reaction products, which can cause safety hazards and diminish efficiency. We selected citric acid, a food-grade substance, as an acidifying agent to evaluate its efficiencies for organic contaminant removal in Fenton's reaction, and examined the impacts of using citric acid on the unwanted reaction products. A series of batch and column experiments were performed with varyingmore » H{sub 2}O{sub 2} concentrations to decompose selected chlorinated ethylenes. Either dissolved iron from soil or iron sulfate salt was added to provide the iron catalyst in the batch tests. Batch experiments revealed that both citric and sulfuric acid systems achieved over 90% contaminant removal rates, and the presence of iron catalyst was essential for effective decontamination. Batch tests with citric acid showed no signs of pressure accumulation and solid precipitations, however the results suggested that an excessive usage of H{sub 2}O{sub 2} relative to iron catalysts (Fe{sup 2+}/H{sub 2}O{sub 2} < 1/330) would result in lowering the efficiency of contaminant removal by iron chelations in the citric acid system. Column tests confirmed that citric acid could provide suitable acidic conditions to achieve higher than 55% contaminant removal rates.« less
Martín-Sómer, Ana; Mó, Otilia; Yáñez, Manuel; Guillemin, Jean-Claude
2015-01-21
The intrinsic acidity of CH2[double bond, length as m-dash]CHXH2, HC[triple bond, length as m-dash]CXH2 (X = N, P, As, Sb) derivatives and of their complexes with BeH2 and BH3 has been investigated by means of high-level density functional theory and molecular orbital ab initio calculations, using as a reference the ethyl saturated analogues. The acidity of the free systems steadily increases down the group for the three series of derivatives, ethyl, vinyl and ethynyl. The association with both beryllium dihydride and borane leads to a very significant acidity enhancement, being larger for BeH2 than for BH3 complexes. This acidity enhancement, for the unsaturated compounds, is accompanied by a change in the acidity trends down the group, which do not steadily decrease but present a minimum value for both the vinyl- and the ethynyl-phosphine. When the molecule acting as the Lewis acid is beryllium dihydride, the π-type complexes in which the BeH2 molecules interact with the double or triple bond are found, in some cases, to be more stable, in terms of free energies, than the conventional complexes in which the attachment takes place at the heteroatom, X. The most important finding, however, is that P, As, and Sb ethynyl complexes with BeH2 do not behave as P, As, or Sb Brønsted acids, but unexpectedly as Be acids.
Seol, Yongkoo; Javandel, Iraj
2008-06-01
Fenton's reagent, a solution of hydrogen peroxide and ferrous iron catalyst, is used for an in situ chemical oxidation of organic contaminants. Sulfuric acid is commonly used to create an acidic condition needed for catalytic oxidation. Fenton's reaction often involves pressure buildup and precipitation of reaction products, which can cause safety hazards and diminish efficiency. We selected citric acid, a food-grade substance, as an acidifying agent to evaluate its efficiencies for organic contaminant removal in Fenton's reaction, and examined the impacts of using citric acid on the unwanted reaction products. A series of batch and column experiments were performed with varying H2O2 concentrations to decompose selected chlorinated ethylenes. Either dissolved iron from soil or iron sulfate salt was added to provide the iron catalyst in the batch tests. Batch experiments revealed that both citric and sulfuric acid systems achieved over 90% contaminant removal rates, and the presence of iron catalyst was essential for effective decontamination. Batch tests with citric acid showed no signs of pressure accumulation and solid precipitations, however the results suggested that an excessive usage of H2O2 relative to iron catalysts (Fe2+/H2O2<1/330) would result in lowering the efficiency of contaminant removal by iron chelation in the citric acid system. Column tests confirmed that citric acid could provide suitable acidic conditions to achieve higher than 55% contaminant removal rates.
Lu, Ying; Li, JiaYin; Li, MiLu; Hu, Xia; Tan, Jun; Liu, Zhong Hua
2012-10-01
Two new cinnamic acids, 2-O-caffeoyl-3-O-isoferuloyltartaric (3), and 2, 3-di-O-isoferuloyltartaric acid (5), along with three known caffeic acids, cichoric acid (1), 2-O-caffeoyl-3-O-feruloyltartaric acid (2) and 2-O-caffeoyl-3-O-p-coumaroyltartaric acid (4), have been successfully isolated and purified from Echinacea purpurea. In this study, we investigated an efficient method for the preparative isolation and purification of cinnamic acids from E. purpurea by high-speed counter-current chromatography (HSCCC). The separation was performed using a two-phase solvent composed of n-hexane-ethyl-acetate-methanol-0.5% aqueous acetic acid (1:3:1:4, v/v). The upper phase was used as the stationary phase and the lower phase as the mobile phase, with a flow rate of 1.6 mL/min. From 250 mg of crude extracts, 65.1 mg of 1, 8.3 mg of 2, 4.0 mg of 3, 4.5 mg of 4, and 4.3 mg of 5 were isolated in one-step, with purities of 98.5%, 97.7%, 94.6%, 94.3%, and 98.6%, respectively, as evaluated by HPLC-DAD. The chemical structures were identified by electro spray ionization mass spectrometry (ESI-MS) and one- and two-dimensional NMR spectra. HSCCC was very efficient for the separation and purification of the cinnamic acids from
An Assay of Selected Serum Amino Acids in Patients with Type 2 Diabetes Mellitus.
Drábková, Petra; Šanderová, Jana; Kovařík, Jakub; kanďár, Roman
2015-01-01
Amino acids are the building blocks of proteins. In case of insulin resistance, which is typical for type 2 diabetes mellitus (T2DM), proteolysis is increased and protein synthesis is decreased; therefore, we can observe changes in the levels of amino acids in diabetics vs. non-diabetics. The aim of this study was to find differences in the levels of selected amino acids between patients with diabetes (type 2) and a control group. Amino acids were derivatized with naphthalene-2,3-dicarboxaldehyde in the presence of potassium cyanide to form fluorescent 1-cyanobenz(f)isoindole product. Amino acids derivatives were measured using a high-performance liquid chromatography with fluorescence detection. The serum levels of glucose were determined using an automatic biochemistry analyzer, glycated hemoglobin HbA1c was measured by cation exchange chromatography. A total of 19 serum amino acids in T2DM patients and non-diabetics were measured. There were 9 amino acids, which were significantly different in these groups (p<0.05). Significantly decreased levels of arginine, asparagine, glycine, serine, threonine and significantly increased levels of alanine, isoleucine, leucine, valine in diabetics were found. Significant difference in metabolism of amino acids between diabetics and non-diabetics were observed. The altered levels of amino acids in diabetic patients could be a suitable predictor of diabetes.
Ji, Bin; Zhao, Yunli; Zhang, Qili; Wang, Pei; Guan, Jiao; Rong, Rong; Yu, Zhiguo
2015-09-15
A simple and rapid ultra-high performance liquid chromatography-tandem mass spectrometry (UHPLC-MS/MS) method was developed for the simultaneous determination of cinnamaldehyde, cinnamic acid, and 2-methoxy cinnamic acid in rat whole blood. It was the first time to study the pharmacokinetics of 2-methoxy cinnamic acid in rat whole blood. Samples were processed by a one-step protein precipitation with acetonitrile-37% formaldehyde (90:10, v:v). Chromatographic separation was performed on a Thermo Scientific C18 column (2.1mm×50mm, 1.9μm) at room temperature. The total run time was 4min. The detection was accomplished by using positive and negative ion electrospray ionization in multiple reaction monitoring mode. The method was linear for all of the analytes over 1000 times concentration range with correlation coefficients greater than 0.99. The lower limits of quantification (LLOQ) were 0.1ng/mL for cinnamaldehyde, 5.8ng/mL for cinnamic acid, and 10ng/mL for 2-methoxy cinnamic acid, respectively. To our knowledge, this was the first time that the LLOQ for cinnamaldehyde in validated methods for biological samples was as low as 0.1ng/mL. Intra- and inter-day precision and accuracy were within ±9% for all of the analytes during the assay validation. Assay recoveries were higher than 80% and the matrix effects were minimal. The half-life were 8.7±0.7h for cinnamaldehyde, 1.0±0.5h for cinnamic acid, and 1.4±0.4h for 2-methoxy cinnamic acid, respectively. The validated assay was firstly applied to the simultaneous quantification of cinnamaldehyde, cinnamic acid, and 2-methoxy cinnamic acid, especially for 2-methoxy cinnamic acid in rat whole blood after oral administration of 15mg/kg essential oil of Cinnamoni Ramulus. It was observed that the Cmax and AUC of 2-methoxy cinnamic acid (0.01% in essential oil of Cinnamoni Ramulus) were greater than those of cinnamaldehyde (83.49% in essential oil of Cinnamoni Ramulus), which implied that 2-methoxy cinnamic acid might be the major bioactive constitutes in essential oil of Cinnamoni Ramulus. Copyright © 2015 Elsevier B.V. All rights reserved.
Nancy You, Yi-Qian; Ling, Pei-Ra; Qu, Jason Zhensheng; Bistrian, Bruce R.
2011-01-01
Background Fatty acid absorption patterns can have a major impact on the fatty acid composition in the portal, intestinal lymph, and systemic circulation. This study sought to determine the effects of long-chain triglycerides (LCT), medium-chain triglycerides (MCT), and 2-monododecanoin (2mono) on intestinal fatty acid composition during continuous feeding over a brief period. Methods The lipid sources were 100% LCT, 100% MCT, a 50:50 mixture of LCT and MCT (LCT/MCT), and a 50:50 mixture of LCT and 2mono (LCT/2mono). A total of 27 rats were randomly given 1 of the 4 diets at 200 kcal/kg/d, with 30% of total calories from lipids over 3 hours. Results MCT significantly increased each of the medium-chain fatty acids (C6:0, C8:0, and C10:0) as free fatty acids in the portal vein and about 10%/mol of C10:0 as triglycerides in the lymph compared with the other groups. There was significantly less C10:0 in lymphatic triglycerides with LCT/MCT than with MCT, but more than in the LCT and LCT/2mono diets. MCT also significantly increased the contents of C16:0, C18:0, C18:1, and C20:4 in the lymphatic triglycerides compared with all other groups including LCT/MCT. The amount of linoleic acid (C18:2) in lymphatic triglycerides followed the relative amounts of this fatty acid in the diet, with the greatest in LCT followed by LCT/MCT and LCT/2mono and least in MCT. A so-called structured lipid composed of the medium-chain fatty acid dodecanoic acid on the 2 position and long-chain fatty acids on the 1 and 3 positions appeared to be endogenously synthesized in response to the LCT/2mono diet. Conclusions The original differences in MCT and LCT content in the diets were preserved in the fatty acid composition in the intestinal free fatty acids and triglycerides during feeding. In addition, the duration of lipid administration can play a role in altering fatty acid composition in the intestine. PMID:18407910
Wewer Albrechtsen, Nicolai J; Junker, Anders E; Christensen, Mette; Hædersdal, Sofie; Wibrand, Flemming; Lund, Allan M; Galsgaard, Katrine D; Holst, Jens J; Knop, Filip K; Vilsbøll, Tina
2018-01-01
Patients with type 2 diabetes (T2D) and patients with nonalcoholic fatty liver disease (NAFLD) frequently exhibit elevated plasma concentrations of glucagon (hyperglucagonemia). Hyperglucagonemia and α-cell hyperplasia may result from elevated levels of plasma amino acids when glucagon's action on hepatic amino acid metabolism is disrupted. We therefore measured plasma levels of glucagon and individual amino acids in patients with and without biopsy-verified NAFLD and with and without type T2D. Fasting levels of amino acids and glucagon in plasma were measured, using validated ELISAs and high-performance liquid chromatography, in obese, middle-aged individuals with I) normal glucose tolerance (NGT) and NAFLD, II) T2D and NAFLD, III) T2D without liver disease, and IV) NGT and no liver disease. Elevated levels of total amino acids were observed in participants with NAFLD and NGT compared with NGT controls (1,310 ± 235 µM vs. 937 ± 281 µM, P = 0.03) and in T2D and NAFLD compared with T2D without liver disease (1,354 ± 329 µM vs. 511 ± 235 µM, P < 0.0001). Particularly amino acids with known glucagonotropic effects (e.g., glutamine) were increased. Plasma levels of total amino acids correlated to plasma levels of glucagon also when adjusting for body mass index (BMI), glycated hemoglobin (Hb A1c ), and cholesterol levels (β = 0.013 ± 0.007, P = 0.024). Elevated plasma levels of total amino acids associate with hyperglucagonemia in NAFLD patients independently of glycemic control, BMI or cholesterol - supporting the potential importance of a "liver-α-cell axis" in which glucagon regulates hepatic amino acid metabolism. Fasting hyperglucagonemia as seen in T2D may therefore represent impaired hepatic glucagon action with increasing amino acids levels. NEW & NOTEWORTHY Hypersecretion of glucagon (hyperglucagonemia) has been suggested to be linked to type 2 diabetes. Here, we show that levels of amino acids correlate with levels of glucagon. Hyperglucagonemia may depend on hepatic steatosis rather than type 2 diabetes.
Efficacy of sanitizers in reducing Salmonella on pecan nutmeats during cracking and shelling.
Beuchat, Larry R; Mann, David A; Alali, Walid Q
2013-05-01
Studies were done to evaluate the efficacy of chlorine (200 to 1,000 μg/ml), lactic acid (0.5 to 2%), levulinic acid (0.5 to 2%), sodium dodecyl sulfate (SDS, 0.05%), lactic acid plus SDS, levulinic acid plus SDS, and a mixed peroxyacid sanitizer (Tsunami 200, 40 and 80 μg/ml) in killing Salmonella on or in immersion- and on surface-inoculated pecan nutmeats (U.S. Department of Agriculture medium pieces and mammoth halves). The addition of SDS to treatment solutions containing lactic acid or levulinic acid resulted in generally higher reductions of Salmonella, but differences in these reductions were not always significant. Lactic and levulinic acids (2%) containing SDS (0.05%) were equivalent in killing Salmonella on immersion-inoculated nutmeats. Tsunami 200 (40 μg/ml) was less lethal or equivalent to 1 or 2% lactic and levulinic acids, with or without 0.05% SDS. Reductions did not exceed 1.1 log CFU/g of immersion-inoculated pieces and halves, regardless of sanitizer concentration or treatment time (up to 20 min). Reductions on surface-inoculated pieces and halves were 0.7 to 2.6 log CFU/g and 1.2 to 3.0 log CFU/g, respectively. Treatment with 2% lactic acid plus SDS (0.05%) and Tsunami (80 μg/ml) was most effective in killing Salmonella on surface-inoculated pieces; treatment of halves with chlorine (1,000 μg/ml) or lactic acid (1 or 2%), with or without SDS, was most efficacious. Exposure of immersion-inoculated pecan pieces to chlorine (200 μg/ml), lactic acid (2%) and levulinic acid (2%) with or without SDS, and Tsunami (80 μg/ml) during intermittent vacuum (18 ± 2 mbar) and ambient atmospheric pressure treatments for up to 20 min reduced Salmonella by only 0.1 to 1.0 log CFU/g. These studies emphasize the importance of preventing contamination of pecan nutmeats with Salmonella. Once nuts are contaminated, the lethality of sanitizers tested in this study is minimal.
2006-09-01
lowering agents (gemfibrozil, clofibric acid ), diuretic agents (furosemide)and the antiepileptic drug valproic acid (Benet et al, 1993; see Bailey and...exposure to the insecticide permethrin is usually performed by analysis of its urinary metabolite 3-phenoxybenzoic acid (3- PBA). However, chronic low...permethrin metabolites 3-PBA and cis/trans-3-(2,2-dichlorovinyl)-2,2-dimethylcyclopropane-1-carboxylic acid (cis/trans-Cl2CA) will form persistent
Ballester, M; Revilla, M; Puig-Oliveras, A; Marchesi, J A P; Castelló, A; Corominas, J; Fernández, A I; Folch, J M
2016-10-01
APOA2 is a protein implicated in triglyceride, fatty acid and glucose metabolism. In pigs, the APOA2 gene is located on pig chromosome 4 (SSC4) in a QTL region affecting fatty acid composition, fatness and growth traits. In this study, we evaluated APOA2 as a candidate gene for meat quality traits in an Iberian × Landrace backcross population. The APOA2:c.131T>A polymorphism, located in exon 3 of APOA2 and determining a missense mutation, was associated with the percentage of hexadecenoic acid [C16:1(n-9)], linoleic acid [C18:2(n-6)], α-linolenic acid [C18:3(n-3)], dihomo-gamma-linolenic acid [C20:3(n-6)] and polyunsaturated fatty acids (PUFAs) in backfat. Furthermore, this SNP was associated with the global mRNA expression levels of APOA2 in liver and was used as a marker to determine allelic expression imbalance by pyrosequencing. We determined an overexpression of the T allele in heterozygous samples with a mean ratio of 2.8 (T/A), observing a high variability in the allelic expression among individuals. This result suggests that complex regulatory mechanisms, beyond a single polymorphism (e.g. epigenetic effects or multiple cis-acting polymorphisms), may be regulating APOA2 gene expression. © 2016 Stichting International Foundation for Animal Genetics.
Crystal engineering of stable temozolomide cocrystals.
Babu, N Jagadeesh; Sanphui, Palash; Nangia, Ashwini
2012-10-01
The antitumor prodrug temozolomide (TMZ) decomposes in aqueous medium of pH≥7 but is relatively stable under acidic conditions. Pure TMZ is obtained as a white powder but turns pink and then brown, which is indicative of chemical degradation. Pharmaceutical cocrystals of TMZ were engineered with safe coformers such as oxalic acid, succinic acid, salicylic acid, d,l-malic acid, and d,l-tartaric acid, to stabilize the drug as a cocrystal. All cocrystals were characterized by powder X-ray diffraction (PXRD), single crystal X-ray diffraction, and FT-IR as well as FT-Raman spectroscopy. Temozolomide cocrystals with organic acids (pK(a) 2-6) were found to be more stable than the reference drug under physiological conditions. The half-life (T(1/2)) of TMZ-oxalic and TMZ-salicylic acid measured by UV/Vis spectroscopy in pH 7 buffer is two times longer than that of TMZ (3.5 h and 3.6 h vs. 1.7 h); TMZ-succinic acid, TMZ-tartaric acid, and TMZ-malic acid also exhibited a longer half-life (2.3, 2.5, and 2.8 h, respectively). Stability studies at 40 °C and 75 % relative humidity (ICH conditions) showed that hydrolytic degradation of temozolomide in the solid state started after one week, as determined by PXRD, whereas its cocrystals with succinic acid and oxalic acid were intact at 28 weeks, thus confirming the greater stability of cocrystals compared to the reference drug. The intrinsic dissolution rate (IDR) profile of TMZ-oxalic acid and TMZ-succinic acid cocrystals in buffer of pH 7 is comparable to that of temozolomide. Among the temozolomide cocrystals examined, those with succinic acid and oxalic acid exhibited both an improved stability and a comparable dissolution rate to the reference drug. Copyright © 2012 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Bryant, F.O.; Rogers, J.E.
1990-02-01
Pentachlorophenol, 2,4-dichlorophenoxyacetic acid and 2,4,5-trichlorophenoxyacetic acid were transformed by microbial reductive dechlorination in freshwater, anaerobic sediments from such diverse locations as Georgia, Florida, New York and the Soviet Union. The reductive dechlorination process involves removal of a chlorine and replacement with a hydrogen. Sediments previously adapted to dechlorinate dichlorophenols were found to mediate dechlorination at much faster rates than unadapted sediments. Pentachlorophenol dechlorination in dichlorophenol-adapted sediments generated tetra-, tri-, di-, and monochlorophenol and phenol. Concentrations of pentachlorophenol, 2,4-dichlorophenoxyacetic acid and 2,4,5-trichlorophenoxyacetic acid up to 100 ppm were dechlorinated by adapted sediments. Reductive dechlorination of PCP, 2,4-D, and 2,4,5-T was regionmore » specific for chlorine removal as determined by the dichlorophenol isomer used to adapt the sediment. Sediment adapted to 2,4-dichlorophenol preferentially removed chlorines from the ortho position; whereas sediment adapted to 3,4-dichlorophenol preferentially removed chlorines from the para position.« less
Hamid, Kaiser; Ng, Irene; Tallapragada, Vikram J; Váradi, Linda; Hibbs, David E; Hanrahan, Jane; Groundwater, Paul W
2016-09-01
The ursane triterpenoids, asiatic acid 1 and madecassic acid 2, are the major pharmacological constituents of Centella asiatica, commonly known as Gotu Kola, which is used traditionally for the treatment of anxiety and for the improvement of cognition and memory. Using the two-electrode voltage-clamp technique, these triterpenes, and some semisynthetic derivatives, were found to exhibit selective negative modulation of different subtypes of the GABAA receptor expressed in Xenopus laevis oocytes. Despite differing by only one hydroxyl group, asiatic acid 1 was found to be a negative modulator of the GABA-induced current at α1 β2 γ2L, α2 β2 γ2L and α5 β3 γ2L GABAA receptors, while madecassic acid 2 was not. Asiatic acid 1 exhibited the greatest effect at α1 β2 γ2L (IC50 37.05 μm), followed by α5 β3 γ2L (IC50 64.05 μm) then α2 β2 γ2L (IC50 427.2 μm) receptors. Conversion of the carboxylic acid group of asiatic acid 1 to a carboxamide group (2α,3β,23-trihydroxy-urs-12-en-28-amide 5) resulted in enhanced inhibition at both the α1 β2 γ2L (IC50 14.07 μm) and α2 β2 γ2L receptor subtypes (IC50 28.41 μm). The results of this study, and the involvement of α5 -containing GABAA receptors in cognition and memory, suggest that asiatic acid 1 may be a lead compound for the enhancement of cognition and memory. © 2016 John Wiley & Sons A/S.
Extraterrestrial Amino Acids in the Almahata Sitta Meteorite
NASA Technical Reports Server (NTRS)
Glavin, Daniel P.; Aubrey, Andrew D.; Callahan, Michael P.; Dworkin, Jason P.; Elsila, Jamie E.; Parker, Eric T.; Bada, Jeffrey L.
2009-01-01
Amino acid analysis of a meteorite fragment of asteroid 2008 TC(sub 3) called Almahata Sitta was carried out using reverse-phase high-perfo rmance liquid chromatography coupled with UV fluorescence detection a nd time-of-flight mass spectrometry (HPLC-FD/ToF-MS) as part of a sam ple analysis consortium. HPLC analyses of hot-water extracts from the meteorite revealed a complex distribution of two- to six-carbon aliph atic amino acids and one- to three carbon amines with abundances rang ing from 0.5 to 149 parts-per-billion (ppb). The enantiomeric ratios of the amino acids alanine, Beta-amino-n-butyric acid (Beta-ABA), 2-amino-2- methylbutanoic acid (isovaline), and 2-aminopentanoic acid (no rvaline) in the meteorite were racemic (D/L approximately 1), indicat ing that these amino acids are indigenous to the meteorite and not te rrestrial contaminants. Several other non-protein amino acids were also identified in the meteorite above background levels including alpha -aminoisobutyric acid (alpha-AIB), 4-amino-2- methybutanoic acid, 4-a mino-3-methylbutanoic acid, and 3-, 4-, and 5-aminopentanoic acid. Th e total abundances of isovaline and AlB in Almahata Sitta are approximately 1000 times lower than the abundances of these amino acids found in the CM carbonaceous meteorite Murchison. The extremely love abund ances and unusual distribution of five carbon amino acids in Almahata Sitta compared to Cl, CM, and CR carbonaceous meteorites and may be due to extensive thermal alteration of amino acids on the parent aster oid by partial melting during formation or impact shock heating.
40 CFR 721.3031 - Boric acid (H3BO3), zinc salt (2=3).
Code of Federal Regulations, 2010 CFR
2010-07-01
... 40 Protection of Environment 30 2010-07-01 2010-07-01 false Boric acid (H3BO3), zinc salt (2=3... Substances § 721.3031 Boric acid (H3BO3), zinc salt (2=3). (a) Chemical substance and significant new uses subject to reporting. (1) The chemical substance identified as boric acid (H3BO3), zinc salt (2=3) (PMN P...
40 CFR 721.3031 - Boric acid (H3BO3), zinc salt (2=3).
Code of Federal Regulations, 2011 CFR
2011-07-01
... 40 Protection of Environment 31 2011-07-01 2011-07-01 false Boric acid (H3BO3), zinc salt (2=3... Substances § 721.3031 Boric acid (H3BO3), zinc salt (2=3). (a) Chemical substance and significant new uses subject to reporting. (1) The chemical substance identified as boric acid (H3BO3), zinc salt (2=3) (PMN P...
Catalytic Ring Hydrogenation of Benzoic Acid with Supported Transition Metal Catalysts in scCO2
Wang, Hongjun; Zhao, Fengyu
2007-01-01
The ring hydrogenation of benzoic acid to cyclohexanecarboxylic acid over charcoal-supported transition metal catalysts in supercritical CO2 medium has been studied in the present work. The cyclohexanecarboxylic acid can be produced efficiently in supercritical CO2 at the low reaction temperature of 323 K. The presence of CO2 increases the reaction rate and several parameters have been discussed.
Yanagisawa, Tatsuo; Kawakami, Makoto
2003-07-11
Two isoleucyl-tRNA synthetases (IleRSs) encoded by two distinct genes (ileS1 and ileS2) were identified in pseudomonic acid (mupirocin)-producing Pseudomonas fluorescens. The most striking difference between the two IleRSs (IleRS-R1 and IleRS-R2) is the difference in their abilities to resist pseudomonic acid. Purified IleRS-R2 showed no sensitivity to pseudomonic acid even at a concentration of 5 mm, 105 times higher than the Ki value of IleRS-R1. The amino acid sequence of IleRS-R2 exhibits eukaryotic features that are originally found in eukaryotic proteins. Escherichia coli cells transformed with the ileS2 gene exerted pseudomonic acid resistance more than did those transformed with ileS1. Cells transformed with both genes became almost as resistant as P. fluorescens. These results suggest that the presence of IleRS-R2 could be the major reason why P. fluorescens is intrinsically resistant to the antibiotic. Here we suggest that the evolutionary scenario of the eukaryotic ileS2 gene can be explained by gene acquisition and that the pseudomonic acid producer may have maintained the ileS2 gene to protect itself from pseudomonic acid.
NASA Technical Reports Server (NTRS)
Lewer, P.; Bandurski, R. S. (Principal Investigator)
1987-01-01
An improved synthesis of 7-hydroxy-2-oxoindolin-3-ylacetic acid via the base-induced condensation reaction between oxalate esters and 7-benzyloxyindolin-2-one is described. 7-Benzyloxyindolin-2-one was prepared in four steps and 50% overall yield from 3-hydroxy-2-nitrotoluene. The yield of the title compound from 7-benzyloxyindolin-2-one was 56%. This route was used to prepare 7-hydroxy-2-oxoindolin-3-yl[13C2]acetic acid in 30% yield from [13C2]oxalic acid dihydrate. The method could not be extended to the preparation of the corresponding [14C2]-compound. However, an enzyme preparation from Zea mays roots catalysed the conversion of carrier-free [5-n-3H]indol-3-ylacetic acid with a specific activity of 16.7 Ci mmol-1 to a mixture of 7-hydroxy-2-oxo[5-n-3H]indolin-3-ylacetic acid and its [5-n-3H]-7-O-glucoside in ca. 3 and 40% radiochemical yield respectively. The glucoside was converted into the 7-hydroxy compound in 80% yield by means of beta-glucosidase.
Hutchins, G. D.; Perry, K.; Territo, W.; Chisholm, R.; Acton, A.; Glick-Wilson, B.; Considine, R. V.; Moberly, S.; DeGrado, T. R.
2015-01-01
Altered myocardial fuel selection likely underlies cardiac disease risk in diabetes, affecting oxygen demand and myocardial metabolic flexibility. We investigated myocardial fuel selection and metabolic flexibility in human type 2 diabetes mellitus (T2DM), using positron emission tomography to measure rates of myocardial fatty acid oxidation {16-[18F]fluoro-4-thia-palmitate (FTP)} and myocardial perfusion and total oxidation ([11C]acetate). Participants underwent paired studies under fasting conditions, comparing 3-h insulin + glucose euglycemic clamp conditions (120 mU·m−2·min−1) to 3-h saline infusion. Lean controls (n = 10) were compared with glycemically controlled volunteers with T2DM (n = 8). Insulin augmented heart rate, blood pressure, and stroke index in both groups (all P < 0.01) and significantly increased myocardial oxygen consumption (P = 0.04) and perfusion (P = 0.01) in both groups. Insulin suppressed available nonesterified fatty acids (P < 0.0001), but fatty acid concentrations were higher in T2DM under both conditions (P < 0.001). Insulin-induced suppression of fatty acid oxidation was seen in both groups (P < 0.0001). However, fatty acid oxidation rates were higher under both conditions in T2DM (P = 0.003). Myocardial work efficiency was lower in T2DM (P = 0.006) and decreased in both groups with the insulin-induced increase in work and shift in fuel utilization (P = 0.01). Augmented fatty acid oxidation is present under baseline and insulin-treated conditions in T2DM, with impaired insulin-induced shifts away from fatty acid oxidation. This is accompanied by reduced work efficiency, possibly due to greater oxygen consumption with fatty acid metabolism. These observations suggest that improved fatty acid suppression, or reductions in myocardial fatty acid uptake and retention, could be therapeutic targets to improve myocardial ischemia tolerance in T2DM. PMID:26732686
Gurtler, Joshua B; Bailey, Rebecca B; Jin, Tony Z; Fan, Xuetong
2014-10-17
A 2011 outbreak of hemorrhagic colitis, which resulted in the death of two individuals, was associated with contaminated strawberries. A study was conducted to identify antimicrobial washes effective at reducing E. coli O157:H7 and Salmonella enterica from the surface of fresh whole strawberries during two-minute immersion washes. Twenty-seven antimicrobial treatments were tested. Vacuum perfusion was applied to strawberries during chlorine and peracetic acid treatments to promote infiltration of sanitizer into porous strawberry tissue. Strawberries were inoculated to 7.1logCFU/strawberry with a seven-strain bacterial composite, consisting of three strains of E. coli O157:H7 and four serovars of Salmonella enterica. Berries were air-dried for 2h and immersed in circulating antimicrobial solutions for 120s at 22°C. Four treatments reduced ≥3.0logCFU/strawberry, including (a) 1% acetic acid+1% H2O2, (b) 30% ethanol+1% H2O2, (c) 90ppm peracetic acid, and (d) 1% lactic acid+1% H2O2. Two additional treatments that reduced 2.8logCFU/strawberry were (a) 40% ethanol, and (b) 1% each of phosphoric+fumaric acids. Eight treatments reduced 2.0-2.6logCFU/strawberry. Five treatments reduced <1.45CFU/strawberry, including (a) 1% citric acid, (b) 1% lactic acid, (c) 1% acetic acid, (d) 0.5% each of acetic+citric acids and (e) 0.5% each of acetic+lactic acids. The use of vacuum perfusion with 200ppm chlorine or 90ppm peracetic acid did not reduce greater populations of pathogens than did the same treatments without vacuum perfusion. Fourteen treatments reduced no more pathogens (p<0.05) than did sterile deionized water. Results from this study provide some options for end-point decontamination of strawberries for retail operations just prior to serving to customers. Published by Elsevier B.V.