Antioxidant Effects and Probiotic Properties of MS103 Isolated from Sweet Pickled Garlic

Fermented vegetable-based foods, renowned for their unique flavors and human health benefits, contain probiotic organisms with reported in vitro antioxidative effects. This study investigates the probiotic properties of MS103 ( MS103) and its antioxidant activities using an in vitro oxidative stress model based on the hydrogen peroxide (HO)-induced oxidative damage of RAW 264.7 cells. MS103 exhibited tolerance to extreme conditions (bile salts, low pH, lysozyme, HO), antibiotic sensitivity, and auto-aggregation ability. Moreover, MS103 co-aggregated with pathogenic cells, inhibited -induced biofilm formation, and exhibited robust hydrophobic and electrostatic properties that enabled it to strongly bind to gingival epithelial cells and HT-29 cells for enhanced antioxidant effects. Additionally, MS103 exhibited other antioxidant properties, including ion-chelating capability and the ability to effectively scavenge superoxide anion free radicals, hydroxyl, 2,2'-azino-bis (3-ethylbenzothiazoline-6-sulfonic acid, and 2,2-diphenyl-1-picrylhydrazyl. Furthermore, the addition of live or heat-killed MS103 cells to HO-exposed RAW 264.7 cells alleviated oxidative stress, as reflected by reduced malondialdehyde levels, increased glutathione levels, and the up-regulated expression of four antioxidant-related genes ( and ). These findings highlight MS103 as a potential probiotic capable of inhibiting activities of pathogenic bacteria and mitigating oxidative stress.