Characterization of Lactic Acid Bacteria from Mandai, a Traditional Fermented Food, as Probiotic Candidates with Potential Gut-Brain Axis Benefits Agustin Krisna Wardani*, Fadilah Nur Ramadhani S, Revalina M Rahmah, Feronika Heppy S
Department of Food Science and Biotechnology, Faculty of Agricultural Technology, Universitas Brawijaya, Malang 65145
Email:agustinwardani[at]ub.ac.id
Abstract
Anxiety disorders are increasingly prevalent mental health conditions that significantly impair quality of life, especially among individuals in their productive years. Recent research highlights the potential of probiotics to alleviate anxiety symptoms by modulating the gut-brain axis through interactions with the gut microbiota. Mandai, a traditional fermented food made from cempedak rind in South Kalimantan, is known to contain lactic acid bacteria (LAB) with probiotic potential. This study aimed to identify the LAB isolate M3 from mandai using molecular methods and evaluate its probiotic properties. Molecular identification was conducted via 16S rRNA gene sequencing, while characterization included morphological and biochemical analyses, hemolytic activity, antibiotic susceptibility, antibacterial activity, tolerance to low pH and bile salts, as well as cell surface properties such as auto-aggregation and hydrophobicity. The isolate was identified as Pediococcus acidilactici M3, a Gram-positive, catalase-negative, and KOH-negative bacterium. It produced 1.82% total acidity with a final pH of 3.96, exhibited non-hemolytic behavior, showed sensitivity to multiple antibiotics, and demonstrated broad-spectrum antibacterial activity. Moreover, it tolerated acidic conditions (pH 2.5-3.5) and bile salt concentrations (0.3-0.6%), with high auto-aggregation (83.45%) and moderate hydrophobicity (26.48%). These results suggest that Pediococcus acidilactici M3 fulfilled key probiotic criteria and holds promise as a functional food-based intervention to promote gut health and potentially alleviate anxiety through the gut-brain axis.
