Changes in Diversity of Intestinal Butyrate-producing Bacteria During Treatment with Shenling Baizhusan and Lizhongtang in Animal Model of AAD / 中国实验方剂学杂志

Objective:To explore the microecological mechanisms of Shenling Baizhusan （SLBZ） and Lizhongtang （LZ） in treating antibiotic-associated diarrhea （AAD） based on changes in the diversity of intestinal butyrate-producing bacteria. Method:SD rats were randomly divided into an SLBZ group （5.5 g·kg^-1·d^-1） and an LZ group （5.5 g·kg^-1·d^-1）. The gut microbiota disturbance model was induced by intragastric administration of clindamycin hydrochloride （315 mg·kg^-1·d^-1） and AAD model by <italic>Clostridium difficile</italic>. Subsequently， the rats were treated correspondingly. Fecal samples at different stages were collected and the total DNA was extracted. Polymerase chain reaction （PCR） amplification was performed with the primers of butyryl coenzyme A （CoA）-CoA transferase genes. The PCR products were cloned and sequenced to analyze the diversity response of butyrate-producing bacteria. Result:After treatment， both groups showed increased food uptake， formed feces， glossy and smooth fur， and improved activity and sensitivity. With the butyryl CoA-CoA transferase gene as the molecular marker， 297 sequences of butyrate-producing bacteria in the SLBZ group （SPD for short） and 300 sequences of butyrate-producing bacteria in the LZ group （LPD for short） were obtained. In the SLBZ group， 98， 100， and 99 sequences of SPD were obtained at the normal stage， the modeling stage， and the treatment stage， respectively， belonging to 8， 3， and 6 operational taxonomic units （OTUs）， with similarity ranges of 78%-97%， 86%-99% ， and 81%-97%. The number of OTUs recovered to 75% of the normal level after treatment. In the LZ group， 100 sequences of LPD were obtained at the normal stage， the modeling stage， and the treatment stage， respectively， belonging to 6， 2， and 4 OTUs， with similarity ranges of 83%-97%， 92%-99%， and 85%-99%. The number of OTUs recovered to 80% of the normal level after treatment. Butyrate-producing bacteria were present in all stages of the two groups， dominated by Firmicutes， accounting for more than 98% of the total number. The effects of SLBZ on SPD at the genus level were observed in the significant decrease in <italic>Clostridium</italic> abundance and the significant increase in <italic>Eubacterium</italic> abundance. The effect of LZ on LPD was mainly concentrated on the <italic>Roseburia </italic>at the genus level， and LZ also increased the abundance of <italic>Eubacterium</italic>， <italic>Lacrimi</italic>sp<italic>ora</italic>， and <italic>Clostridium</italic>. According to the phylogenetic tree， the classification of butyrate-producing bacteria increased from five clusters to seven clusters after SLBZ treatment， while that increased from three clusters to nine clusters after LZ treatment. Conclusion:In the treatment of AAD， SLBZ and LZ can regulate the structure and abundance of butyrate-producing bacteria in the intestine， restore their diversity， and improve the instability of the intestinal microecological environment.

Advances in Pharmacological Research of Traditional Chinese Medicine Based on "Butyric Acid Producing Bacteria-Polysaccharides of Traditional Chinese Medicine" / 中国实验方剂学杂志

The latest research shows that the intestinal flora is closely related to the pharmacology of traditional Chinese medicine（TCM）, and the study of microecological mechanism is a new direction of pharmacology of TCM. Among many functional groups of intestinal flora, butyric acid producing bacteria is an important functional group of intestinal flora. It can ferment dietary fiber, carbohydrate, endogenous protein and so on to produce metabolites. The imbalance of its flora is also related to the occurrence of a variety of diseases. The reason is that butyric acid is an important secondary metabolite of butyrobacteria. As an important short chain fatty acid, butyric acid can maintain intestinal health, regulate immune system and inflammatory response, regulate energy metabolism, and affect cell fraction Chemokines and apoptosis play an important role. Polysaccharide of TCM has the characteristics of high content, not easy to be digested and absorbed by the host, but can be decomposed and utilized by intestinal flora. It can be used as the carbon source of bacteria to regulate the intestinal flora, including butyric acid producing bacteria, and improve the structure of intestinal flora to achieve the purpose of disease treatment. Therefore, based on "butyric acid producing bacteria-polysaccharide of TCM", it is a new field in the study of microecological mechanism of TCM to study the pharmacology of TCM from the function of intestinal bacteria and the polysaccharide component of flora carbon source. Based on the latest literature and microecological pharmacology of TCM, this paper reviews the role of butyric acid, the molecular mechanism of butyric acid producing bacteria using polysaccharide of TCM, the relationship between polysaccharide of TCM and butyric acid producing bacteria, and discusses the relationship between butyric acid producing bacteria and polysaccharide of TCM. It also looks forward to the research of TCM pharmacology based on "butyric acid producing bacteria-polysaccharide of TCM", in order to provide a reference for the research progress of TCM pharmacology based on "butyric acid producing bacteria-polysaccharide of TCM".

Research Progress of Polysaccharide Utilization Loci and Its Application in Pharmacological Research of Chinese Medicinal Herb / 中国实验方剂学杂志

Polysaccharide utilization loci (PULs) are a group of gene clusters related to polysaccharides catabolism and located in specific areas, including starch utilization system(SusC), SusD, encoding outer membrane glycoprotein binding proteins, and carbohydrate active enzymes. The wide existence of PULs in Bacteroides, and the extraordinary ability of utilizing polysaccharide is its survival strategy to adapt to the intestinal tract. On one hand, Bacteroides feature a high abundance and variety, making it the most important bacterial target group regulated by traditional Chinese medicine(TCM). On the other hand, polysaccharide is an important effective constituent among TCM chemicals, with a high content, and can also be used as a competitive carbon source for intestinal bacteria. Therefore, what is the mechanism of regulating the intestinal flora based on the carbon source of polysaccharide is an important part of the pharmacological research of TCM. According to the latest literatures, this paper introduces the gene and protein composition of PULs, reviews the latest developments in PULs research, and analyzes the structure of PULs in the genomes of Bacteroides fragilis and Bacteroides thetaiotaomicron. Furthermore, we also put forward a prospect for the pharmacological micro-ecological mechanism of TCM based on PULs based on our carbon source experiments, which focuses the effects of Bacteroides by TCM polysaccharides in vitro. This research is not only the new content of bacterial PULs researches, but also the important part of researches of "human-drug-bacteria" holistic view and TCM spleen-tonifying concept.