Eurotium cristatum, a new fungi probiotic from Fuzhuan brick tea, alleviated obesity in mice by modulating gut microbiota

Abstract

Obesity is one of the major public health problems worldwide, mainly resulting from unhealthy lifestyles and diet. Gut microbiota dysbiosis may also lead to obese humans and animals. Modulating gut bacteria through fecal transplantation, the use of probiotics or certain dietary supplements, could normalize gut microbiota and subsequently alleviate obesity. Daily consumption of Fuzhuan brick tea (FBT) or its extracts have been observed to alleviate obesity in humans and experimental animals. In this study, high-fat diet-induced dysbiosis of gut microbiota in C57BL/6J mice was partially reversed by consumption of Eurotium cristatum, the dominant fungi during the manufacturing and storage of FBT. E. cristatum was able to modulate both gut fungi and bacteria composition, based on the analysis of microbiota composition of mice fecal samples. E. cristatum increased acetate and butyrate-producing bacteria in mice gut, and produced five times more butyrate than both obese and normal mice. Our results suggested that E. cristatum may be used as a fungi probiotic to beneficially modulate gut microbiota and to alleviate obesity in humans. ResultsE. cristatum may survive in mouse intestine. In order to clarify if E. cristatum could survive during tea brewing and consumption, 10 4 spores of E. cristatum isolated from FBT, were heated in water containing 20% (v/v) glycerol at 50, 70, 80, 85, 90 and 100 °С for 2, 5 or 10 min, respectively (Supplemental Fig.1). E. cristatum survived even after 10 min in 90 °С and 2 min in 100 °С. E. cristatum was next mixed with drinking water and fed to Kunming mice. E. cristatum could be isolated from mouse feces, even without feeding of E. cristatum for two weeks (Supplemental Fig. 2). There were no significant differences in body weight among mice fed with or without E. cristatum, as well as mice fed with the water extracts or filtered water extracts of Fuzhuan brick tea. These results suggested that E. cristatum from Fuzhuan brick tea is non-toxic and could survive in mice intestine. E. cristatum reduced HFD-induced obesity in C57BL/6J mice. The HFD-induced C57BL/6J obese mouse model was used to explore if live E. cristatum may have any antiobesity effect, in comparison to mice that received normal chow diet (NCD). The high-fat diet mice that received FBT or filtered Fuzhuan brick tea (FFBT), in which live E. cristatum were removed by filtering the FBT extracts using a 0.22 µm filter, were also used as controls ( Fig. 1a-e). The mice in HFD group showed significant increases in body and liver weights, and epididymal fat accumulation, compared with mice in the NCD group ( Fig. 1ae). In contrast, the high-fat diet mice that received E. cristatum (10 3 CFU/day) in drinking water showed significantly decreased body weight gain, liver weight and epididymal fat accumulation. The FFBT-treated mice also showed significant decrease in liver and

Isolation and Characterization of Benzaldehyde Derivatives with Anti-Inflammatory Activities from Eurotium cristatum, the Dominant Fungi Species in Fuzhuan Brick Tea

“…cristatum should be present in one gram of FBT, based on the manufacturing protocol enforced by current regulations . We have recently discovered that the FBT-derived fungi may survive in the mouse gut and could normalize gut microbiota dysbiosis in obese mice …”

“…11 We have recently discovered that the FBT-derived fungi may survive in the mouse gut and could normalize gut microbiota dysbiosis in obese mice. 12 The unique postfermentation process of FBT using E. cristatum has enabled special phytochemical profiles of FBT extracts, including tea polyphenols, 13 flavones, 14 triterpenoids, 15 norisoprenoid, 16 and polysaccharides. 17 These unique metabolites were suggested to play important roles to mediate these important health benefits in humans and experimental animals.…”