Lactic acid bacteria-fermented product of green tea and Houttuynia cordata leaves exerts antiadipogenic and anti-obesity effects

Obesity is associated with higher risks of developing diabetes and cardiovascular disease.Green tea, rich in polyphenolic compounds such as epigallocatechin gallate (EGCG) andepigallocatechin (EGC), has been shown to display anti-obesity effects. Houttuynia cordataleaves have also been shown to exhibit anti-obesity effects due to their chlorogenic acidcontent. Lactic acid bacteria are able to increase the production of polyphenolic compounds.This study aims to develop a novel anti-obesity fermentation product bycombining H. cordata leaf tea with green tea, using Lactobacillus paracasei subsp. paracaseiNTU 101 (NTU 101) for fermentation due to the advantages of bioconverting the polyphenoliccompounds. The regulation of adipogenesis factors and the anti-obesity effect ofthe NTU 101-fermented tea were evaluated in an in vitro 3T3-L1 pre-adipocyte model andan in vivo obese rat model, respectively. The results show that the NTU 101-fermented tea,which contained higher EGCG, EGC, and chlorogenic acid levels than unfermented tea, wasable to inhibit the lipogenesis of mature 3T3-L1 adipocytes by the stimulation of lipolysis.Furthermore, the body weight gain, body fat pad, and feeding efficiency of obese rats,induced with a high fat diet, were decreased by the oral administration of NTU 101-fermented tea. The significant anti-obesity effect was probably due to lipolysis. However,NTU 101 bacteria cells and EGCG may also act as functional ingredients to contribute to theanti-obesity effects of NTU 101-fermented products.