ABSTRACT
"Lianzhifan solution" (LZF) is produced by the natural fermentation of coptis root and gardenia fruit, and it is a classic prescription for external use in anorectal department. During the fermentation process, the structural evolution of microbial communities led to significant changes in the chemical profile. In this study, we first analyzed the dynamic changes of chemical components as well as the composition and succession of microbial community during the whole fermentation process of LZF, and confirmed the changes of characteristics of nine compounds during the whole fermentation process by metabolic profile. Further analysis found that there was no significant change of alkaloids in all stages of fermentation of LZF, but there were significant changes of iridoids in the middle and late stage of fermentation by deglycosylation. Genipin gentiobioside and geniposide were converted to genipin by biotransformation, showing that deglycosylation was the main event occurring in the fermentation. The community composition and abundance of species in 10 and 19days LZF fermentation broth were analyzed with high-throughput sequencing technology, and 16 dominant bacterial genera and 15 dominant fungal genera involved in the fermentation process were identified. Correlation analysis revealed that Penicillium expansum and Aspergillus niger involved in the fermentation were the dominant genera closely related to the dynamic changes of the deglycosylation of the main chemical components, and P. expansum YY-46 and A. niger YY-9 strains were obtained by the further fractionation. Then the monoculture fermentation process was evaluated, whereby we found that the deglycoside conversion rate of iridoid glycosides was greatly improved and the fermentation cycle was shortened by 3-4 times. This finding combined with equivalence evaluation of chemical component and pharmacodynamics to confirm that P. expansum YY-46 and A. niger YY-9 strains were key strains for fermentation concoction. This study established an efficient and practical screening strategy "Microfauna communities-Chemical component-Pharmacodynamic" axis for key strain, to improve the production process and formulating good manufacturing practice (GMP) work, and it is also applicable to the whole fermentation drugs industry. Graphical AbstractThe figure highly summarizes the research content of this study and shows the screening process of key strains in LZF fermentation.
ABSTRACT
Phlorizin (PHZ) is one of phytonutrients in apples that contributes to the health-promoting effect implicated by the saying, 'an apple a day keeps the doctor away'. PHZ was firstly identified as a competitive inhibitor of sodium-glucose co-transporters-2 (SGLT2); however, its low bioavailability makes it hard to fully explain its pharmacological mechanisms. This study aimed to investigate the ameliorating effect of PHZ on high-fat diet (HFD)-induced obesity via modulating the "gut microbiota-barrier axis". Firstly, C57BL/6 J mice were fed a normal chow diet (NCD) or HFD coadministered with or without PHZ for 12 weeks. Our results showed that PHZ supplementation significantly reduced HFD-induced body weight gain (P < .001), alleviated metabolic disorders (MDs) like insulin resistance (P < .001) and elevation of serum lipopolysaccharides (LPS) (P < .001), attenuated HFD-induced gut microbiota alterations, enhanced short-chain fatty acids (SCFAs) production (P < .001), and inhibited fecal LPS production (P < .001). To investigate the role of the fecal microbiota in the observed beneficial effects, a fecal microbiota transplantation (FMT) experiment was performed by transplanting the feces of the four groups of mice (as donor mice) daily collected from the fourth week to a new batch of acclimatized HFD-fed mice. Our results confirmed that feeding the gut contents of the PHZ-modulated mice could attenuate HFD-induced MDs, accompanied by enhanced glucagon-like peptide 2 (GLP-2) secretion (P < .001) and restoration of HFD-induced damage in the gut epithelial barrier. This study has provided evidence that the "gut microbiota-barrier axis" was an alternative target for the anti-obesity effect of PHZ. This work has also provided an explanation for the high efficacy of PHZ despite the low bioavailability, and PHZ holds great potential to be developed as a functional food ingredient.