Identification of novel probiotic lactic acid bacteria with in vitro antioxidant, antidiabetic, and anti-inflammatory activities

Abstract This study characterised four Algerian food-derived lactic acid bacterium (LAB) strains, Lactiplantibacillus plantarum MA2 (T2), Limosilactobacillus fermentum MA3 (L3), L. fermentum MA4 (L4), and Lactiplantibacillus pentosus MA1 (F2), to explore their potential in combating oxidative stress-related chronic diseases. The strains were assessed for probiotic resilience, antioxidant potential, antidiabetic and anti-inflammatory effects, safety, and antimicrobial activity. All demonstrated strong survival (>75%) and high antioxidant capacity. T2 and L4 displayed notable α -amylase inhibition (68.54 and 54.42%) compared to acarbose (86.20%). T2 also exhibited outstanding anti-inflammatory activity (96.61 ± 0.90%), exceeding diclofenac (93.12 ± 0.35%; P < 0.05). A strong correlation was observed between FRAP and α -amylase inhibition ( r = 0.996). PCA revealed T2 as functionally distinct, linked to anti-inflammatory, DPPH, and SOD-like activities, while L3/L4 clustered with ABTS and FRAP traits. All strains were safe (non-haemolytic, antibiotic-sensitive) and inhibited enteropathogens. T2 and L4 combined strong bioactivity, stress tolerance, and safety, underscoring their probiotic potential against oxidative stress, hyperglycaemia, and inflammation.