Abstract: Chickpea milk fermented with Lactobacillus plantarum UL-4 was found to be enriched in γ-aminobutyric acid (GABA). Moreover, the probiotic characteristics of strain UL-4 were evaluated by measuring its acid and salt tolerance, cell surface properties, antibacterial activity, and cholesterol and triglyceride degradation activity. Results showed that the viable cell count was 7.81 (lg(CFU/mL)) after 48 h fermentation and the GABA yield was 371.14 mg/L. The survival rates of the strain were respectively 46.67%, 91.81%, and 174.21% at pH 2, 3, and 4; 382.83%, 91.81%, and 56.28% at bile salt concentrations of 0.03%, 0.15%, and 0.3%, demonstrating strong acid and salt resistance. Its cell surface hydrophobicity and auto-aggregation were 52.49% and 61.50%, respectively, and it had adhesion and colonization ability in the intestine. The strain had potent antimicrobial activity, which inhibited the growth of Escherichia coli, Staphylococcus aureus, and Salmonella typhimurium with inhibition zone diameters of 14.40, 15.77, and 13.36 mm, respectively. Furthermore, the strain could degrade cholesterol and triglyceride with degradation rates of 73.23% and 19.11%, respectively. In summary, L. plantarum UL-4 could ferment chickpea milk enriched in GABA, and also showed good probiotic characteristics, making it a candidate for developing functional foods.

Key words: Lactobacillus plantarum, γ-aminobutyric acid, chickpea milk, probiotic characteristics