通过对体内外抗氧化效应比较,探讨了嗜热链球菌(Streptococcus thermophilus)grx90发酵豆乳的抗氧化活性。结果表明,豆乳(SM)、活茵豆乳(SMC)、发酵豆乳(FSM)、巴氏杀菌发酵豆乳(PFSM)清除DPPH能力和亚铁离子螯合能力存在不同程度差异性,发现FsM体外抗氧化作用显著高于PFSM、SMC@SM;FSM显著降低了急性酒精肝损伤模型小鼠血清ALT和AST,提高了肝组织中SOD和GSH-Px活性,并显著降低肝组织中MDA含量。体内外实验进一步证实了发酵豆乳抗氧化活性的增强主要是基于乳酸茵活茵体及其代谢产物,并通过增强机体抗氧化酶活性,降低过氧化物的积累以增强抗氧化能力,从而实现对酒精诱导小鼠急性氧化损伤的保护作用。
This study was aimed at evaluating the antioxidant effects of soymilk fermented with Streptococcus thermophilus grx90 in vitro and in vivo. The results showed that soymilk (SM), lactic acid bacteria/sOymilk mixture (SMC), fermented soymilk (FSM) and pasteurized fermented soymilk (PFSM) had different capacity for scavenging 2, 2-diphenyl-l-picrylhydrazyl (DPPH) and chelating ferrous ion, and FSM had the most potent capacity. In vivo, as to acute alcoholic liver injury model mice, FSM obviously reduced serum alanine transarninase (ALT) and aspartate transaminase (AST) levels, elevated liver tissue suPeroxide dismutase (SOD) and glutathione perioxidase (GSH-Px) activities, and malondialdehyde (MDA) content was decreased. It was confirmed that lactic acid bacteria and its metabolites may enhance the antioxidant activities of soymilk during fermentation. FSM may enhance antioxidant enzymes activities, reduce the accumulation of peroxides to enhance antioxidant capacity, thereby protecting acute alcohol liver injury caused by oxidative stress.