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91.
Kevin Lewellyn Dobroslawa Bialonska Melissa J. Loria Stephen W. White Kenneth J. Sufka Jordan K. Zjawiony 《Bioorganic & medicinal chemistry》2013,21(22):7083-7090
Aplysinopsins are tryptophan-derived natural products that have been isolated from a variety of marine organisms and have been shown to possess a range of biological activities. In vitro receptor binding assays showed that of the 12 serotonin receptor subtypes, analogues showed a high affinity for the 5-HT2B and 5-HT2C receptor subtypes, with selectivity for 5-HT2B over 5-HT2C. While no conclusions could be drawn about the number and position of N-methylations, bromination at C-4 and C-5 of the indole ring resulted in greater binding affinities, with Ki’s as low as 35 nM. This data, combined with previous knowledge of the CNS activity of aplysinopsin analogs, suggested that these compounds may have potential as leads for antidepressant drugs. Compounds 3c, 3u, and 3x were evaluated in the chick anxiety–depression model to assess their in vivo efficacy. Compound 3c showed a modest antidepressant effect at a dose of 30 nM/kg in the animal model. 相似文献
92.
常军 《天然产物研究与开发》2013,25(8):1085-1088
本文建立了一个快速高效的HPLC方法同时检测苦杏仁苷及其4个体外酶解产物,色谱分析系统为安捷伦液相色谱系统,自动进样器,迪马ODS C18色谱柱(250 mm×4.6 mm,5μm),柱温25℃,流动相30%甲醇,检测波长210 nm,进样量10μL。结果表明,苦杏仁苷、phenyl-(3,4,5-trihydroxy-6-methyl-tetrahydro-pyran-2-yloxy)-acetonitrile、野樱花苷、苯甲醛和杏仁腈的保留时间分别为5.087、13.836、16.357、22.775和3.307 min。该HPLC方法的重现性好,精确度和准确度高,当柱温低于30℃、pH值介于6.0~7.0时该方法结果稳定、重现性好。 相似文献
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96.
《Bioscience, biotechnology, and biochemistry》2013,77(4):930-932
Glyceraldehyde (200 mM) and Nα-acetyllysine (100 mM) were incubated in 0.2 M sodium phosphate buffer (pH 7.4) at 37°C for a week. A major compound, glyceraldehyde-related Maillard reaction product, was purified from the reaction mixture using reverse phase (ODS)-HPLC. It was identified as 1-(5-acetylamino-5-carboxypentyl)-3-hydroxy-5-hydroxymethyl-pyridinium, named as GLAP (Glyceraldehyde derived Pyridinium compound), using NMR and MS analyses. It was suggested that GLAP as a novel advanced glycation end product (AGE) is one of the key compounds in the glyceraldehyde-related Maillard reaction. 相似文献
97.
本研究从食品微生物指标人手,对我国肉类食品的微生物指标检测情况及其产品质量进行分析,在相关政府部门的有力的监管下,肉类产品质量与安全有了较大幅度提高.最后分析了我国肉类食品行业的现存问题,并提出改进的建议,最后对其发展进行展望. 相似文献
98.
《Journal of Plant Interactions》2013,8(2):69-81
Abstract Allelopathy is defined as the suppression of any aspect of growth and/or development of one plant by another through the release of chemical compounds. Although allelopathic interference has been demonstrated many times using in vitro experiments, few studies have clearly demonstrated allelopathy in natural settings. This difficulty reflects the complexity in examining and demonstrating allelopathic interactions under field conditions. In this paper we address a number of issues related to the complexity of allelopathic interference in higher plants: These are: (i) is a demonstrated pattern or zone of inhibition important in documenting allelopathy? (ii) is it ecologically relevant to explain the allelopathic potential of a species based on a single bioactive chemical? (iii) what is the significance of the various modes of allelochemical release from the plant into the environment? (iv) do soil characteristics clearly influence allelopathic activity? (v) is it necessary to exclude other plant interference mechanisms?, and (vi) how can new achievements in allelopathy research aid in solving problems related to relevant ecological issues encountered in research conducted upon natural systems and agroecosystems? A greater knowledge of plant interactions in ecologically relevant environments, as well as the study of biochemical pathways, will enhance our understanding of the role of allelopathy in agricultural and natural settings. In addition, novel findings related to the relevant enzymes and genes involved in production of putative allelochemicals, allelochemical persistence in the rhizosphere, the molecular target sites of allelochemicals in sensitive plant species and the influence of allelochemicals upon other organisms will likely lead to enhanced utilization of natural products for pest management or as pharmaceuticals and nutraceuticals. This review will address these recent findings, as well as the major challenges which continue to influence the outcomes of allelopathy research. 相似文献
99.
《Archives of animal nutrition》2013,67(6):445-446
Abstract Schenk/Kolb: Grundriß der physiologischen Chemie, 6. überarbeitete Auflage. Erschienen im VEB Gustav Fischer Verlag Jena, 1971. Mit 116 Abb. und 237 Tab., Ganzleinen, Format 10,5 × 24,5 cm. Preis: 30,—M. Reviewed by H. Bergner. H. Bergner: Energie — Leben — Leistung — Nahrung. Erschienen im Urania-Verlag Leipzig-Jena-Berlin 1971, 144 Seiten, mit 49 Abb. und 25 Tab., Ganzleinen, Format 14,5 × 21,5 cm, Preis: 9,80 M. Reviewed by H. Haenel. G. Dirksen, W. Kaufmann und E. Pfeffer: Untersuchungen zur Verdauungs physiologie der Milchkuh mit der Umleitungstechnik am Duodenum. Erschienen im Verlag Paul Parey, Hamburg und Berlin 1972. 43 Seiten mit 10 Abb. und 22 Tab., kart., Format 16,5 × 25 cm, Preis: 22,00 DM (als Beiheft zur Z. Tierphys. Tierernähr. Futtermittelkd., für Bezicher der Zeitschrift 20,35 DM). Reviewed by H. Bergner. 相似文献
100.
天然产物及其衍生物在现代医疗中扮演着举足轻重的角色,其生物活性多样性以及化学结构的丰富性是新药研发的源泉和动力。利用纯化学方法合成天然产物在技术和成本上有很大的困难,加上许多天然产物的原始产生菌具有培养条件苛刻、产量低下等缺点,而且大量基因簇在原始菌株中是沉默的,这使得利用合成生物学思想来指导天然产物生物合成基因簇的异源表达具有重大意义。作为抗生素、抗肿瘤活性物质、免疫抑制剂等次级代谢产物主要来源的放线菌一直是研究者们关注的焦点,特别是随着基因测序技术的飞速发展,人们发现链霉菌基因组中包含着极为丰富的天然产物生物合成基因簇资源。这意味着开发链霉菌底盘细胞作为异源表达宿主有其得天独厚的优势。本综述从底盘细胞开发的意义入手,重点阐述链霉菌底盘细胞构建的策略及现状,随后通过实例阐述了各种底盘链霉菌的实际应用。 相似文献