日本农药工业投入农药生物工程研究开发

由17家主要的农药公司组成的“农药生物工程开发技术研究组合”(由日本农药株式会社社长小平祐担任理事长)从1990年起分别承担下列研究课题。 1.微生物、酶转化利用技术的开发: (1) 中外制药公司——利用微生物(酶)进行不对称合成反应的技术开发。 (2) 日产化学公司——利用微生物(酶)进行光学活性农药生产的技术开发。 (3)日本曹达公司——利用微生物代谢物转化为农药的技术开发。     

生物信息学应用于代谢物组学研究的进展

如何利用代谢物组的海量数据和信息,与其他领域整合并重构完整的生化网络,建立预测细胞表型、优化生化过程和评价药物安全性的崭新方法是生物信息学需要解决的重要问题.本文综述了代谢物组数据分析中应用的主要生物信息学方法及关键问题,列举了各种方法在植物、微生物及哺乳动物体系的重要应用.最后对代谢物组学的前景进行展望.     

DNA甲基化与肠道微生物研究进展

肠道内的微生物群在维持肠道健康方面起着至关重要的作用。微生物表观遗传修饰包括DNA甲基化、组蛋白修饰、染色质重塑等。本文综述了环境因素对肠道微生物群、表观遗传修饰及其在肠道微生物和相关癌症发病过程中DNA甲基化领域的研究成果,对利用肠道微生物治疗相关癌症有一定的参考价值。     

他感物质——开发新除草剂的理想先导物质

随着人类对环境越来越高的要求,人们更加注重于生物源农药的开发.农药科学家们不仅将具有农药活性的生物源物质或其代谢物直接作为农药使用,例如B.t等各种活体微生物、阿维菌素等各种微生物代谢物(即农用抗生素)、烟草和印楝等各种植物、斑蝥等动物,而且更致力于以天然物质为先导物,经结构改造或化学修饰后开发新的农药.由微生物源物质Strobilurin为先导物开发的甲氧基丙烯酸类农药,迄今已有10个商品;由植物源物质烟碱为先导物开发的烟酰亚胺类杀虫剂,已有8个产品问世;由虾、蟹等动物废壳开发的壳聚糖类农药等.目前,人们又兴起了以植物中的他感物质(allelochemical)作为开发新农药的先导物.     

赭曲霉代谢物及其衍生物的杀菌活性研究

西班牙Lleida研究开发中心在深入研究微生物源医药、农药有用物质过程中发现,次级代谢物具有广泛的生物活性。进入抗菌素年代前,很少发现具有抗菌活性的微生物制品,而称谓麦角生物碱的真菌代谢物是唯一例外。经过化学家坚持不懈努力,提纯麦角药物有效成份有了结果,1907年分离出麦角碱。虽然19世纪末,就确定了微生物拮抗作用的生化基础,但并未引起化学家的强烈兴趣。1896年Gosio首先提到抗细菌的真菌代谢物:霉酚酸,     

系统生物学技术在微生物菌种改良中的应用

生物工业不断探索新方法来改良微生物菌株.系统生物学技术的重要目标是通过大量的组学数据分析来阐明细胞功能,已经为菌种改进提供了新技术.作者综述了基因组、转录组、蛋白组、代谢物组以及代谢流组等系统生物学技术在微生物菌种改良中的应用,进而展望了基于系统水平改进微生物菌种的发展方向.     

肠道菌群对中草药有效成分转化研究

肠道中的肠道菌群一般会与口服药物发生作用,对药物的生物转化起非常重要的作用。国内外许多学者对中药在肠道菌群作用下的转化做了研究,本文就此进行综述。肠道菌群对中药代谢的研究方法主要有在体和离体两种,涉及代谢物的定性、定量,生物酶系及菌种的研究。中药有效成分中的环烯醚萜类、黄酮类、生物碱及蒽醌等化合物都可以经肠道菌群代谢,形成新的活性化合物,对提高生物利用度和增加药物疗效有重要作用。     

以微生物代谢物进行除草剂开发的研究进展

概述了以微生物代谢产物进行除草剂研究的主要方向,即以下5个方面:筛选微生物从中分离具有除草活性的新化合物;对高除草活性的微生物菌株的市场化研究;对微生物源高活性化合物的全合成或结构改造;对微生物源除草活性系列化合物的构效关系研究;对天然除草活性化合物的作用机制研究。这些研究表明,以微生物代谢物进行除草剂的研究仍将是除草剂开发的一个重要热点。     

生物样品中短链脂肪酸的分析方法研究进展

短链脂肪酸(Short-Chain Fatty Acids, SCFAs)是膳食纤维在肠道中经微生物代谢后的主要终产物,是肠道微生物与宿主间重要的信息传递使者。SCFAs作为关键介质直接或间接在机体多个器官和组织中发挥着重要的生理作用,其准确定量对于研究生物体内SCFAs的产生、变化规律,对于揭示肠道微生物与人类健康之间复杂关系具有重要的意义。SCFAs在人体内分布广泛,具有分子量小、易挥发、紫外吸收弱等特点,且不同生物样品之间种类及含量相差较大,因此SCFAs分析检测方法一直是研究的难点。在系统介绍SCFAs的来源、种类及分布的基础上,对其常用的分析检测方法进行总结,以期为进一步开发高效和灵敏的SCFAs分析方法提供参考。     

高效微生物饲料添加剂

一、国内外研究应用现状 微生物添加剂(Microbial additives)是对包括益生素(probiotics)、微生态制剂在内的有益微生物制剂的一种广义和通俗的解释,又名活菌剂、生菌剂、促生素、利生素等。它的核心含义是指摄入动物体内参与肠道内微生物平衡的具有直接通过增强动物对胃肠内有害微生物群落的抑制作用,或通过增强非特异或特异性免疫功能来预防疾病,     

Fatty Acid Biomarkers of Symbionts and Unusual Inhibition of Tetracosapolyenoic Acid Biosynthesis in Corals (Octocorallia)

Seven zooxanthellae-free species of octocorals (the genera Acanthogorgia, Acabaria, Chironephthya, Echinogorgia, Menella, Ellisella, and Bebryce) and two zooxanthellate octocorals (the genera Paralemnalia and Rumphella) were examined to elucidate their fatty acid (FA) composition. Arachidonic (about 40% of the total FA) and palmitic acids were predominant in all the species studied. Seven furan FA (F-acids) (up to 9.7%) were identified in the azooxanthellate octocorals. The main F-acids were 14,17-epoxy-15-methyldocosa-14,16-dienoic and 14,17-epoxy-15,16-dimethyldocosa-14,16-dienoic acids. In all specimens of Bebryce studeri, C_25–28 demospongic FA (about 20%) were identified. These FA reflect the presence of a symbiotic sponge in B. studeri and can be used as the specific markers for other corals. A significant difference (P < 0.01) between azooxanthellate and zooxanthellate corals was found for odd-chain and methyl-branched saturated FA, 18:1n-7, and 7-Me-16:1n-10; that indicated the presence of an advanced bacterial community in azooxanthellate corals. The zooxanthellate species were distinguished by significant amounts of 18:3n-6, 18:4n-3, and 16:2n-7 acids, which are proposed as the markers of zooxanthellae in soft corals. Contrary to the normal level of 24:5n-6 (9.4%) and 22:4n-6 (0.6%), unexpected low concentrations of 24:5n-6 (0.4%) accompanied by a high content of 22:4n-6 (up to 11.9%) were detected in some specimens. The presence of an unknown factor in octocorals, specific for n-6 PUFA, which inhibited elongation of 22:4n-6 to 24:4n-6, is conjectured.     

GC-EI-MS Analysis of Fatty Acid Composition in Brain and Serum of Twitcher Mouse

Globoid cell leukodystrophy or Krabbe disease is an inherited autosomal recessive disorder caused by mutations in the galactosylceramidase gene. The objective of the study was to present information about the fatty acid (FA) composition of the brain and serum of twitcher mice, a mouse model of Krabbe disease, compared to wild type, in order to identify biomarker of disease progression. We defined the FA profiles by identifying the main components present in serum and brain using GC‐EI‐MS analysis. The FA percentage composition was measured and data were analyzed considering the disease and the mouse age as experimental factors. Significant correlations were established, both in brain and in serum, in the fatty acid percentage composition of twitcher compared to wild type mice. The most abundant saturated fatty acid in brain was the palmitic acid (C16:0) with mean values significantly increased in twitcher mouse (p = 0.0142); moreover, three monounsaturated, three polyunsaturated (PUFA) and a plasmalogen were significantly correlated to disease. In the serum highly significant differences were observed between the two groups for three polyunsaturated fatty acids. In fact, the docosahexaenoic acid (C22:6n3c) content was significantly increased (p = 0.0116), while the C20 PUFA (C20:3n6c and C20:5n3c) were significantly decreased in twitcher serum samples. Our study shows a specific FA profile that may help to define a possible pattern that could distinguish between twitcher and wild type; these data are likely to provide insight in the identification of new biomarkers to monitor the disease progression and thereby permit the critical analysis of therapeutic approaches.     

褐煤和柴煤中腐植酸的测定

本国际标准介绍了褐煤和柴煤中腐植酸的测定方法。第二版（ISO5073：1999）是在对第一版（ISO5073：1985）进行技术修改后形成的。本版鹰植酸的测定咀相对比较简单酌容量法取代了重量法（ISO5073：1985）同时附录A还介绍了预先测定腐植酸含碳比的方法。     

羧酸类配位聚合物的研究进展

羧酸类金属配位聚合物是一种新型功能性分子材料,近年来得到科学家的普遍关注。本文对羧酸类金属配位聚合物的分类进行了综述,综述了羧酸类金属配位聚合物研究的重要性和国内外羧酸类金属配位聚合物的研究工作,对苯多羧酸类、吡啶羧酸类、草酸类、脂肪族二羧酸类配合物在手性拆分和催化、分子磁体、非线性光学方面的研究进行了详细介绍,列举了近年来这类配位聚合物的研究成果和开发进展,并对其发展趋势进行了展望。     

A Practical Way to Prepare Isobutyronitrile Amides through Reactions between Carboxylic Acids and Azobisisobutyronitrile

A practical and efficient synthesis of N‐isobutyronitrile amides has been achieved through the direct condensation of carboxylic acid and azobisisobutyronitrile (AIBN). Carboxylic acids bearing variously substituted phenyl rings and cinnamic or phenylpropiolic acids were employed to furnish both tertiary and secondary isobutyronitrile amides in moderate to high yields. A radical pathway was proposed. The methodology presented here requires no catalysts and additives, and represents the first practical approach to a variety of valuable amides containing the isobutyronitrile structural unit.

     

Comparison of fatty acid composition of domestic and imported margarines and frying fats in Bulgaria

A total of 82 dietary fats sold on the Bulgarian market in the period 1995—2000 were analyzed. The samples included 68 table margarines (50 of which were imported), 10 frying fats (6 imported) and 4 salad dressings (all imported). A validated analytical method, thin‐layer chromatography‐AgNO₃‐densitometry, was used. It enabled direct determination of all fatty acid groups, differing by degree of unsaturation and double bonds geometry. Low levels of trans fatty acids (TFA) down to 0.1% of the total for mono trans‐trienoic (Tcct) and mono trans‐dienoic (Dct), and down to 0.2% for trans‐monoenoic (Mt) were quantitated, with an error under 3% and a standard deviation of 0.1—1.5. The total content of TFA in table margarines varied from 0 to 26.9% with a mean value of 8.6 ± 7.2% for imported and 1.6 ± 3.4% for Bulgarian samples. Saturated fatty acids (SFA) content varied from 11.5 to 45.7%, with a mean value of 25.4 ± 5.7% for imported and 26.9 ± 5.2% for Bulgarian margarines. A general trend of lower levels of TFA and SFA in imported margarines was observed over the studied period. Additionally, the content of individual saturated fatty acids was determined by gasliquid chromatography in 37 of all studied samples.     

Reduced Maternal Erythrocyte Long Chain Polyunsaturated Fatty Acids Exist in Early Pregnancy in Preeclampsia

The present prospective study examines proportions of maternal erythrocyte fatty acids across gestation and their association with cord erythrocyte fatty acids in normotensive control (NC) and preeclamptic pregnancies. We hypothesize that maternal fatty acid status in early pregnancy influences fetal fatty acid stores in preeclampsia. 137 NC women and 58 women with preeclampsia were included in this study. Maternal blood was collected at 3 time points during pregnancy (16–20th weeks, 26–30th weeks and at delivery). Cord blood was collected at delivery. Fatty acids were analyzed using gas chromatography. The proportions of maternal erythrocyte α‐linolenic acid, docosahexaenoic acid, nervonic acid, and monounsaturated fatty acids (MUFA) (p < 0.05 for all) were lower while total n‐6 fatty acids were higher (p < 0.05) at 16–20th weeks of gestation in preeclampsia as compared with NC. Cord 18:3n‐3, 22:6n‐3, 24:1n‐9, MUFA, and total n‐3 fatty acids (p < 0.05 for all) were also lower in preeclampsia as compared with NC. A positive association was observed between maternal erythrocyte 22:6n‐3 and 24:1n‐9 at 16–20th weeks with the same fatty acids in cord erythrocytes (p < 0.05 for both) in preeclampsia. Our study for the first time indicates alteration in maternal erythrocyte fatty acids at 16th weeks of gestation which is further reflected in cord erythrocytes at delivery in preeclampsia.     

Methods for increasing estolide yields in a batch reactor

Estolides are formed when the carboxylic acid group of one fatty acid forms an ester link at the site of unsaturation of another fatty acid. These compounds have the potential to be used in a variety of applications, such as lubricants, greases, plastics, inks, cosmetics, and surfactants. By manipulating the reaction equilibrium, yields of 20% estolide in clay-catalyzed estolide reactions have been increased to 30%. Reactions conducted at 180°C, where water was vented out of the reactor at specific times, not only gave dimer-free estolides but also yields up to 30%. Steam has also been used instead of water with similar results. Estolides were quite stable at temperatures up to 250°C, even when they were exposed to air.