Comparative study of the anti-obesity and gut microbiota modulation effects of green tea phenolics and their oxidation products in high-fat-induced obese mice.

• Green tea phenolic profile was changed massively by tyrosinase incubation. • Pre- & post-oxidation of green tea phenolics had similar anti-obesity effect. • Pre- & post-oxidation of green tea phenolics had similar effect on gut microbiota. • Anti-obesity effect of tea was associated with the alteration in gut microbiota. Green and black teas are regarded to possess therapeutic potential for the treatment of obesity, however it is not clear which tea performs better in body weight control. In this study, aiming to eliminate cultivar variation, green tea phenolics (GTP) were oxidized by tyrosinase to obtain oxidized tea phenolics (OTP). Thereafter, their anti-obesity effect on high-fat diet induced obese mice were compared. The results showed that despite their distinctive phenolic profiles, GTP and OTP exerted similar anti-obesity properties after 12 weeks of dietary intervention. Furthermore, cecal microbiota profiling exhibited comparable modulatory effects of GTP and OTP on multiple bacterial taxa, including Parabacteroides distasonis , Bifidobacterium , Prevotella , and Akkermansia muciniphila , which were strongly associated with obesity related indexes. Putative bacterial function profiling implicated that both GTP and OTP might regulate the lipid metabolism similarly. Collectively, the oxidation of GTP did not influence the anti-obesity and gut microbiota modulatory effects to any large extent. [ABSTRACT FROM AUTHOR]