Application of gut microbiota in research of Chinese medicines / 中国中药杂志

This article summarizes the research progress in recent years on interactions between Chinese medicines and gut microbiota based on the physiological functions of gut microbiota, including imbalance impacts of toxic/irritating Chinese medicines on gut microbiota, prognosis effects of Chinese medicines on gut microbiota imbalance, metabolism effects of gut microbiota on Chinese medicine components, and co-metabolism effects between gut microbiota and host. We would think and prospect the specific biological effects of Chinese medicines, gut microbiota structures and the relations between endogenous metabolites from "gut microbiota and host co-metabolism". All of these aim to investigate biological mechanisms and effective components of Chinese medicines based on gut microbiota and offer a new strategy for promoting safe and effective application of Chinese medicines.

Co-metabolism of DDT by the newly isolated bacterium, pseudoxanthomonas sp. wax

Microbial degradation of 1,1,1-trichloro-2,2-bis(p-chlorophenyl)ethane (DDT) is the most promising way to clean up DDT residues found in the environment. In this paper, a bacterium designated as wax, which was capable of co-metabolizing DDT with other carbon sources, was isolated from a long-term DDT-contaminated soil sample by an enrichment culture technique. The new isolate was identified as a member of the Pseudoxanthomonas sp., based on its morphological, physiological and biochemical properties, as well as by 16S rRNA gene analysis. In the presence of 100 mg l-1 glucose, the wax strain could degrade over 95 percent of the total DDT, at a concentration of 20 mg l-1, in 72 hours, and could degrade over 60 percent of the total DDT, at a concentration of 100 mg l-1, in 144 hours. The wax strain had the highest degradation efficiency among all of the documented DDT-degrading bacteria. The wax strain could efficiently degrade DDT at temperatures ranging from 20 to 37ºC, and with initial pH values ranging from 7 to 9. The bacterium could also simultaneously co-metabolize 1,1-dichloro-2,2-bis(p-chlorophenyl)ethane (DDD), 2,2-bis(p-chlorophenyl)-1,1-dichlorethylene (DDE), and other organochlorine compounds. The wax strain could also completely remove 20 mg kg-1 of DDT from both sterile and non-sterile soils in 20 days. This study demonstrates the significant potential use of Pseudoxanthomonas sp. wax for the bioremediation of DDT in the environment.