Biocatalytical Acyl-Modification of Puerarin: Shape Gut Microbiota Profile and Improve Short Chain Fatty Acids Production in Rats.

Gut microbiota balance and metabolites have become a potentially mechanism in maintaining health. The specific aim of this study was to compare the modulation of puerarin and puerarin acid esters on gut microbial composition and metabolites. Male mice were fed a control diet or diets supplemented with puerarin, puerarin propanoate ester, puerarin hexanoate ester, puerarin myristate ester for 24 h, respectively. The result revealed that puerarin acid esters with different chain lengths showed different activities to create more own impacted bacterial. Puerarin propanoate and puerarin hexanoate ester significantly improved the diversity of microbiota and promoted the relative abundance of beneficial gut microbiota such as Lactobacillus, Barnesiella, Clostridium IV, Prevotella. Additionally, the puerarin propanoate ester group showed the capacity to deliver specific propionic acid to the colon. But esters with medium-long chain lengths had more opportunity to alter gut microbiota for enhancing the short chain fatty acids production. As a whole, puerarin acid esters with different chain lengths supplements shaped different gut microbial and short chain fatty acids metabolism, which could improve human health.

Animal study of the anti-diarrhea effect and microbial diversity of dark tea produced by the Yao population of Guangxi.

Chinese dark teas (CDTs) are a special type of tea traditionally consumed by ethnic minorities around the border regions of China. Dark tea produced by the Yao population of Guangxi could help prevent diarrhea following the heavy consumption of food. However, the underlying mechanisms behind this effect are not clear. This study aimed to investigate the function and underlying mechanisms of dark tea by examining the effects of different doses of dark tea on diarrhea in mice caused by Folium Sennae. It was found that dark tea could significantly improve the rate of loose stools and diarrhea index, and had an inhibitory effect on intestine peristalsis in high- and moderate-dose groups. Compared with green tea, significantly decreased levels of water extract, tea polyphenol and amino acid were found in dark tea, whereas the content of both caffeine and gallocatechin was increased. The result of dilution plating showed that Aspergillus niger and Byssochlamys fulva were consistent with microbial diversity as assessed by high-throughput sequencing technology. A total of 12 metabolites related to an anti-diarrhea effect were identified by ultra-performance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS). These findings provide a physiological basis for developing dark tea produced by the Yao population of Guangxi as a drink that can regulate and improve the intestinal flora in humans.