In modern society, numerous metabolic disorders are widespread globally. The present study aimed to demonstrate whether Bacillus subtilis-fermented Amomum xanthioides (BSAX) exerts anti-metabolic disturbance effects compared with the ethyl acetate fraction of Amomum xanthioides (EFAX), a previously verified functional fraction. Mice fed with a high-fat, high-fructose diet (HFHFD) for 10 wk presented a typical model of metabolic dysfunction, and BSAX significantly attenuated a string of metabolic-syndrome-related pathological parameters, such as body, fat, organ mass, lipid markers (TGs, TC, free fatty acids), and glucose metabolism (glucose, insulin), without influencing appetite. Further, BSAX markedly lowered malondialdehyde (MDA) and ROS in the blood and restored antioxidative parameters (SOD, GSH, and CAT in liver tissue, and total bilirubin in serum) by elevating Nrf2 and HO-1. Moreover, BSAX noticeably restored gut microbiota diversity and normalized lipid-metabolism-associated proteins, including SREBP-1, p-AMPK, and PPAR-α. Generally, most metabolic parameters were improved by BSAX to a greater extent than EFAX, except for liver weight and hepatic TC. In conclusion, BSAX alleviates metabolic dysfunction by enhancing lipid metabolism and antioxidative capacity and is more effective than EFAX. Therefore, the application of high-yield, effective BSAX might be a promising approach for curing and preventing metabolic disorders.
Keywords: Amomum xanthioides; Bacillus subtilis; fermentation; gut microbiota; metabolic diseases; oxidative stress.