Antioxidant and Anti-inflammatory Activities of Latilactobacillus curvatus and L. sakei Isolated from Green Tripe

Background/Objectives: Green tripe (GRET) is rich in essential fatty acids, vitamins, calcium, phosphorus, and other nutrients and contains various beneficial microorganisms, including lactobacillus, along with feed components consumed by ruminants. Methods: In this study, Latilactobacillus sakei and L. curvatus were isolated from GRET and evaluated for their potential as probiotics, focusing on their anti-inflammatory properties and ability to modulate inflammatory responses. Results: When heat-killed L. sakei or L. curvatus (10⁸ CFU/mL) and their metabolites (0.5 mg/mL) were applied to RAW 264.7 macrophages stimulated with LPS, nitric oxide (NO) production was reduced by approximately 10–35% and 2–11%, respectively. Furthermore, the expression levels of key anti-inflammatory cytokines, TNF-α and IL-6, were suppressed by more than 5%. These effects were not due to cytotoxicity but instead due to genuine anti-inflammatory activity. In addition, both strains exhibited antioxidant activity, as demonstrated by their performance in ABTS and FRAP assays. Conclusions: These findings suggest that L. sakei and L. curvatus have significant antioxidant and anti-inflammatory properties, highlighting their potential as probiotics and prebiotics. Moreover, these newly isolated strains from GRET are expected to serve as valuable functional ingredients for developing health-promoting foods and dietary supplements.