ISOLATION AND DETERMINATION OF BIOLOGICAL CHARACTERISTICS OF LACTIC ACID BACTERIA FROM PICKLED SAUERKRAUT IN DA LAT

Abstract

Lactic acid bacteria strains (LAB) were isolated from sauerkraut without causing hemolysis; they were screened and identified for their tolerance to acids, bile salts, phenols, pathogenic bacteria and antioxidants. The results obtained contained seven strains of bacilli, Gram-positive, CaCO₃-degrading, negative for catalase, indole, oxidase and not hemolytic which were used to continue with the research. The LDL19 strain was found to have superior properties compared to other strains when resisting Escherichia coli, Pseudomonase aerigunosa and Salmonella sp. In addition, LAB also has resistance to bile salts and acid at pH levels of 2.5 and pH 3.0, reaching 9.01±0.02% and 9.17±0.06, respectively after 3 hours; as well as phenol tolerance at 0.3% and 0.5% respectively after 24 hours, as well as DPPH  free radical scavenging over 40%. The bacteria LDL19 has been identified as Lactobacillus fermentum LDL19, which is sensitive to ampicillin, penicillin, chloramphenicol antibiotics, and moderately sensitive to amikacin antibiotic, as well as a resistance to gentamycin, streptomycin, vancomycin antibiotics. This indicates that L. fermentum LDL19 is considered as one of the bright candidates to be used in the application of dietery supplements.