Modelling of microbial processes that govern degradation of organic substrates in soil, with special reference to pesticides

We tried to develop deterministic models for kinetics of 2,4-D breakdown in the soil based on the following considerations: (i) at low concentrations degradation results from maintenance consumption by a large fraction of the soil microbial population; (ii) at high concentration in addition to the maintenance consumption there is a growth-associated carbon incorporation by a small specific microbial population. Values for the biokinetic parameters are consistent with those commonly found in the literature. Comparison between observed and simulated curves suggests that a non-negligible part of the pesticidal carbon exists as microbial by-products.     

甾体微生物转化在制药工业中的应用

对几种重要的甾体微生物转化反应如甾体边链降解、甾体羟基化反应的机理及其发展与应用作了概述;同时也介绍了固定化微生物细胞、非水溶液中酶催化反应及混合发酵等微生物转化技术在制药工业中的应用。     

甾类化合物微生物转化与分解代谢机制研究进展

甾类化合物具有重要的生理医药作用,市场需求巨大。甾类化合物及其关键甾类药物通过微生物转化制备工艺较化学合成法具有区域立体选择性、减少合成步骤、缩短生产周期、提高收率以及生态友好等优点逐步被应用,然而甾类物质微生物分解代谢机制还有待进一步深入探索研究并确定。本文从甾类化合物结构种类与主要来源、生理功能、微生物转化与分解代谢机制的研究等方面进行了归纳,着重解析甾类化合物分解代谢过程关键酶系及其分子作用机制,为甾药化合物生产菌种改造与工程菌构建,以及微生物转化工业化生产工艺的开发提供参考。     

Subcellular fractionation of Hymenolepis diminuta with special reference to the localization of marker enzymes

A method for subcellular fractionation of Hymenolepis diminuta using whole worm homogenization and differential centrifugation is presented. Different fractions obtained in this study were screened for the presence of enzymes that serve as markers for plasma membrane, brush border, mitochondria, Golgi complex, endoplasmic reticulum, peroxisomes, lysosomes and cytosol. The purity of fractions was also monitored by transmission electron microscopy. The purity of fractions, particularly the brush border membranes, are compared to those obtained by previous methods for H. diminuta or other tissues.