Probiotic Properties of Lactic Acid Bacteria Isolated from Spontaneously Fermented Kunun-Zaki

ABSTRACT

This study was conducted to investigate the probiotic properties of twenty lactic acid bacteria (LAB) previously isolated and identified from naturally fermented kunun-zaki (a Nigerian fermented cereal beverage). The probiotic properties of the twenty lactic acid bacteria (LAB) isolates were assessed using different standard methods and agar well diffusion method. The results showed that most of the isolates tolerated acidic pH and survived at 30-40oC. All the tested LAB isolates grew at 1% NaCl concentration and remarkably, six LAB isolates {L. brevis (3) and L. plantarum (3)} exhibited good growth at higher NaCl concentrations (10-15%). The highest percentage of cellular auto-aggregation was observed in L plantarum (84.86%) and the lowest was obtained in L. brevis (27.44%). All the twenty LAB isolates tested in-vitro in this study grew in bile salt; fermented glucose; produced good aroma; produced no hemolysis revealing they were not pathogenic and produced antagonistic activity against selected pathogens (Staphylococcus aureus, Salmonella typhi, Shigella. dysenteriae and Escherichia coli) which made them suitable and safe for human consumption as potential probiotics and for industrial purposes.