CHARACTERIZATION AND IDENTIFICATION OF THE BEST SCREENED INDIGENOUS LACTIC ACID BACTERIA PRODUCING βββββ-GALACTOSIDASE

Abstract

ß-Galactosidase (EC 3.2.1.23) is an enzyme used in production of low/free lactose milk consumed mainly human which have lactose intolerance. Characteristics of indigenous Lactic acid bacteria (LAB) producing ß-galactosidase haven’t been fully reported. To know the characteristics of the LAB, characterization and identification of the best screened indigenous LAB producing ß-galactosidase were researched. The best LAB was molecularly identified. The crude ß-galactosidase of LAB was produced by centrifugation. The optimum production of the best LAB b-galactosidase was measured based on incubation time, inoculum concentration, pH and lactose concentration. The optimum activity of the ß-galactosidase was measured based on pH and temperature. The ß-galactosidase activity was measured by modified method of Lu et al., 2009. Research results show that 10 (ten) out of 70 (seventy) indigenous LAB produced ß-galactosidase with high activities. LAB producing the highest ß-galactosidase activity than the others was LAB strain B110. The LAB strain B110 was identified molecularly as Lactobacillus plantarum strain B110. The ß-galactosidase optimum production of L. plantarum strain B110 was reached at incubation time for 30 hours, 2% inoculum concentration, medium pH: 7, and 2% lactose concentration. The optimum activity of the ß-galactosidase was reached at temperature of 45o C and pH: 6,5, respectively. Based on selection and characterization of L. plantarum strain B 110, L. plantarum strain B 110 was the best LAB producing ß-galactosidase than that of the other LAB. Keywords : characterization, identification, Lactic Acid Bacteria, ß-galactosidase, indigenous