Journal of Petroleum & Environmental Biotechnology

Molecular characterisation of Lactobacilli isolated from fermented idli batter and evaluation for probiotic potential

Jayaprabha Agaliya P

: Agrotechnol

Abstract:

Lactic acid bacteria (LAB) are non pathogenic organism widely distributed in nature. LAB has an important role in the preservation of foods and fermented products and is designated as GRAS (Generally regarded as safe). They are commercially used as starter cultures in the manufacture of dairy products, fermented vegetables, fermented dough, alcoholic beverages and meat products. In this study, molecular characterization was performed by RAPD, 16S rRNA analysis, 16S ARDRA and Multiplex PCR for species identification for the eight isolates from fermented idli batter. RAPD was carried out using the primer R2 and M13 which resulted in five different clusters. 16S rRNA analysis showed 99 to 100 % homology towards Lactobacillus plantarum. The restriction digestion pattern was similar for all the isolates with the restriction enzyme Alu I. The subspecies were identified by performing Multiplex PCR using species specific primer. The clusters were clearly identified as Lactobacillus plantarum subsp. plantarum, Lactobacillus pentosus and Lactobacillus plantarum subsp. argentoratensis. The isolates were able to tolerate up to 0.3% of bile for 4- 6 hours and pH 2.5, 3.5, 4.5, 6.5, 7.5 and 8.5. The isolates were able to resist growth against gastric and intestinal fluid. The isolates exhibited good levels of auto-aggregation, co-aggregation and hydrophobicity. The isolates showed resistance towards antibiotics like gentamycin, ciprofloxacin, nalidixic acid and norfloxacin. The isolates showed bilesalt hydrolase activity indicating cholesterol lowering capacity and β- galactosidase activity. Thus the different Lactobacillus plantarum isolates exhibited probiotic potential which would attribute beneficial effect to mankind. Keywords: Lactobacillus plantarum, characterisation, probiotic.

Biography :

Jayaprabha Agaliya P is 27 years old, pursuing PhD (Biochemistry & Molecular Biology) under the guidance of Dr. K. Jeevaratnam, Professor & Co-ordinator (Microbiology), Department of Biochemistry & Molecular Biology, Pondicherry University. She completed her B.Sc (M. L. T) from JIPMER and M.Sc (Biochemistry & Molecular Biology) from Pondicherry University. Her research is on isolation and characterisation of antimicrobial substances from lactic acid bacteria and evaluation of probiotic potential of the producer strains.