FFZZH5L isolated from pickled cowpea enhanced antioxidant activity in by upregulating the level of glutathione -transferase.

is a potential probiotic that possesses beneficial health properties and fermentation traits; however, the extent of understanding of the antioxidant activities of is limited. This study investigates the antioxidant activities of a new FFZZH5L strain. The strain exhibits broad tolerance to acids, bases and salts and demonstrated good adaption to the gastrointestinal environment, with a survival rate of 45% after 24 h of treatment in artificial gastrointestinal juice. Moreover, FFZZH5L exhibits inhibitory effects on , with a self-aggregation rate of 34.8% and a co-aggregation rate of 82.2%. , the DPPH radical scavenging ability and GSH-px enzyme activity of FFZZH5L reach 64.27% and 15.95 U mL, respectively. Treatment of with FFZZH5L significantly extended the organism's lifespan. Furthermore, the activity of SOD, GSH-px and T-AOC was increased by 33.6%, 43.4% and 58.3%, respectively. Feeding with FFZZH5L decreased the MDA, lipofuscin and ROS levels by 9%-36.4%. FFZZH5L effectively protected against juglone-induced oxidative stress damage and led to a significant increase in the organism's survival under heat stress. The RT-qPCR analysis suggests that feeding with FFZZH5L upregulates the expression levels of antioxidant-related genes including glutathione -transferase 4 (), , , , , and in . Our investigation confirms the probiotic and antioxidant properties of , indicating its potential application in functional foods and the pharmaceutical industry.