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51.
Bernhard Kienesberger Beate Obermüller Georg Singer Barbara Mittl Reingard Grabherr Sigrid Mayrhofer Stefan Heinl Vanessa Stadlbauer Angela Horvath Wolfram Miekisch Patricia Fuchs Ingeborg Klymiuk Holger Till Christoph Castellani 《International journal of molecular sciences》2021,22(12)
We aimed to assess the in vitro antimicrobial activity and the in vivo effect on the murine fecal microbiome and volatile organic compound (VOC) profile of (S)-reutericyclin. The antimicrobial activity of (S)-reutericyclin was tested against Clostridium difficile, Listeria monocytogenes, Escherichia coli, Enterococcus faecium, Staphylococcus aureus, Staphylococcus (S.) epidermidis, Streptococcus agalactiae, Pseudomonas aeruginosa and Propionibacterium acnes. Reutericyclin or water were gavage fed to male BALBc mice for 7 weeks. Thereafter stool samples underwent 16S based microbiome analysis and VOC analysis by gas chromatography mass spectrometry (GC-MS). (S)-reutericyclin inhibited growth of S. epidermidis only. Oral (S)-reutericyclin treatment caused a trend towards reduced alpha diversity. Beta diversity was significantly influenced by reutericyclin. Linear discriminant analysis Effect Size (LEfSe) analysis showed an increase of Streptococcus and Muribaculum as well as a decrease of butyrate producing Ruminoclostridium, Roseburia and Eubacterium in the reutericyclin group. VOC analysis revealed significant increases of pentane and heptane and decreases of 2,3-butanedione and 2-heptanone in reutericyclin animals. The antimicrobial activity of (S)-reutericyclin differs from reports of (R)-reutericyclin with inhibitory effects on a multitude of Gram-positive bacteria reported in the literature. In vivo (S)-reutericyclin treatment led to a microbiome shift towards dysbiosis and distinct alterations of the fecal VOC profile. 相似文献
52.
Dr. Daisuke Fujiwara Kousuke Mihara Ryo Takayama Yusuke Nakamura Prof. Mitsuhiro Ueda Prof. Takeshi Tsumuraya Prof. Ikuo Fujii 《Chembiochem : a European journal of chemical biology》2021,22(24):3406-3409
Conformationally constrained peptides hold promise as molecular tools in chemical biology and as a new modality in drug discovery. The construction and screening of a target-focused library could be a promising approach for the generation of de novo ligands or inhibitors against target proteins. Here, we have prepared a protein kinase-focused library by chemically modifying helix-loop-helix (HLH) peptides displayed on phage and subsequently tethered to adenosine. The library was screened against aurora kinase A (AurA). The selected HLH peptide Bip - 3 retained the α-helical structure and bound to AurA with a KD value of 13.7 μM. Bip - 3 and the adenosine-tethered peptide Bip - 3 - Adc provided IC50 values of 103 μM and 7.7 μM, respectively, suggesting that Bip - 3 - Adc bivalently inhibited AurA. In addition, the selectivity of Bip - 3 - Adc to several protein kinases was tested, and was highest against AurA. These results demonstrate that chemical modification can enable the construction of a kinase-focused library of phage-displayed HLH peptides. 相似文献
53.
Nuchanart Suealek Thipaporn Tharavanij Robert M. Hackman Carl L. Keen Roberta R. Holt Benjapun Burawat Ammara Chaikan Rattana Tiengtip Panadda Rojpibulstit 《European Journal of Lipid Science and Technology》2021,123(2):2000126
The potential cardiovascular benefit of virgin olive oil (VOO) is widely recognized. However, the use of VOO at very high cooking temperatures makes these oils poorly suited for many Asian dishes. The use of tea seed oil (TSO) is increasing in Thailand, with TSO having a higher smoke point than VOO. The current study examines the effects of daily TSO intake in healthy adults. In a randomized, single-blind crossover design, 12 men consumed for 3 weeks 40 g day−1 of food prepared with either TSO or VOO as a cooking oil. Plasma lipids, thiobarbituric acid reactive substances (TBARS), and oxidant defense enzyme activities are measured before and after each 3-week intervention period. Gas chromatography analysis of TSO and VOO demonstrates that both oils are equally high in monounsaturated fatty acid. The dietary incorporation of TSO and VOO for three weeks reduces low-density lipoprotein cholesterol (LDL-C) concentrations by 15% and 13%, respectively; with total cholesterol (TC) levels lowered by 10% in both groups. No significant changes in TBARS or antioxidant enzyme activity is observed. These results support the concept that Thai TSO can be utilized as a suitable and healthy alternative oil for high-temperature cooking in many Thai and Asian diets. Practical Applications: Tea seed oil from Camellia oleifera grown in Thailand has been recently reported to favorably lower lipid profiles in hamsters fed a high-fat diet in a manner similar to feeding refined olive oil or grapeseed oil. A pilot crossover trial is conducted to compare the effects of three weeks of daily intake of either TSO or VOO in healthy human adults. Consumption of both oils produced significant reductions in TC and LDL-C. Thai TSO leads to favorable lipid profiles and is a reasonable choice for many Thai and Asian food recipes. 相似文献
54.
55.
尿素包合法分离橡胶籽油中的多价不饱和脂肪酸 总被引:8,自引:0,他引:8
用尿素包合法从橡胶籽油混合脂肪酸中分离多价不饱和脂肪酸 ,用正交设计实验法对分离工艺进行研究 ,其最佳分离条件是 :原料配比为m(混合脂肪酸 )∶m(尿素 )∶m(乙醇 ) =1 0 0∶1 5∶1 8,回流时间 12 0min。经一次尿素包合法分离即可得到多价不饱和脂肪酸质量分数大于90 %的产品 ,实验收率大于 35 % 相似文献
56.
KeShun Liu Frank Orthoefer Edward A. Brown 《Journal of the American Oil Chemists' Society》1995,72(2):189-192
Ten soybean genotypes grown in 1992 with seed size ranging from 7.6 to 30.3 g/100 seeds and maturity group V or VI were selected
and tested for oil and protein content and for fatty acid composition. In these germplasm, protein varied from 39.5 to 50.2%,
oil, 16.3 to 21.6%, and protein plus oil, 59.7 to 67.5%. Percentages of individual fatty acids relative to total fatty acids
varied as follows: palmitic, 11.0 to 12.8; stearic, 3.2 to 4.7; oleic, 17.6 to 24.2; linoleic, 51.1 to 56.3 and linolenic,
6.9 to 10.0. Seed size showed no significant correlations with individual saturated fatty acids, protein or oil content. However,
significant correlations were found between seed size and individual unsaturated fatty acids: positive with oleic, and negative
with linoleic and linolenic. Oil and protein content were negatively correlated with each other. Among the major fatty acids,
only the unsaturated were significantly correlated with each other: negative between oleic and linoleic or linolenic, and
positive between linoleic and linolenic. A subsequent study with soybeans grown in 1993 generally confirmed these findings.
Variation in relative percentages of unsaturated fatty acids andr values for most pairs of relationships were even higher than those obtained from the 1992 crop.
Presented at the 85th AOCS Annual Meeting and Expo, Atlanta, Georgia, May 8–12, 1994. 相似文献
57.
58.
Giant hogweed at its northern distribution limit in North America: Experiments for a better understanding of its dispersal dynamics along rivers
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We studied the reproduction and dispersal of giant hogweed (Heracleum mantegazzianum) at its northern distribution limit in North America (Québec, 2014–2016) to better understand the invasion dynamics of the species along rivers. Seeds were collected from a riparian population to conduct germination, floatation, and dispersal experiments. Data were analysed in comparison with a real invasion case that was initiated about 10 years ago along a river system. In Québec, giant hogweed individuals produce on average 14,000 to 16,000 seeds with a germination rate of 75–85%. Seeds with endosperm that fall in water likely sink within 5 hr. Along a small brook, most disperse over short distances (<40 m) in summer, although some can travel 100–300 m. These data suggest that late‐summer or early‐fall water dispersal of seeds would not explain the magnitude and rapidity of the invasion patterns observed along streams. We suggest that late‐fall and, especially, spring floods are the most efficient dispersal vectors for giant hogweed seeds and are likely responsible for the establishment of populations kilometres downstream from introduction points along river systems. The spread of giant hogweed would consequently be less influenced in the near future by a rise in temperature than by a change in the magnitude or timing of flood events. 相似文献
59.
Frédéric Destaillats Jean B. Jean-Denis Joseph Arul Robert L. Wolff Paul Angers 《Journal of the American Oil Chemists' Society》2002,79(11):1091-1094
GC analysis was performed to determine regiospecific distribution and FA composition in seed oils of the Aceraceae species,
Acer saccharum and A. saccharinum. The oil content in the seeds was low at 5.0% in A. saccharum and 5.8% in A. saccharinum, and the main FA were linoleic (30.8 and 29.4%), oleic (21.3 and 27.6%), palmitic (10.1 and 10.5%), and cis-vaccenic (9.4 and 7.9%) acids, respectively. In addition, both oils contained long-chain monoenes of the n−9 and n−7 groups,
including 11-eicosenoic, 13-docosenoic, 15-tetracosenoic, 13-eicosenoic, and 15-docosenoic acids, whereas γ-linolenic acid
accounted for 0.8% of total FA in A. saccharum, and 0.5% in A. saccharinum. Regiospecific analysis, performed using the methodology of dibutyroyl derivatives of MAG, indicated that linoleic, oleic,
and linolenic acids were mainly esterified at the internal position of TAG in both seed oils, whereas long-chain monoenes
of the n−7 group were almost exclusively esterified on the external positions. 相似文献
60.
Oligomerization of glycine (gly) and diglycine (gly2) on montmorillonite was performed as cyclic, drying-wetting process at temperatures below 100°C, under varying reaction conditions. The influence of substrate/clay ratio, temperature and pH was found to be different for amino acid (AA) dimerization, cyclic anhydride (CA) formation and peptide chain elongation. High temperatures and neutral pH favour CA formation over diglycine production. An AA/catalyst ratio of 0.2 mmol/g leads to optimal yields. This supports the assumption that amino acid dimerization and CA formation take place at the edges of clay particles. Peptide chain elongation, starting from gly2, produces higher yields at higher temperatures and neutral pH. 相似文献