Antimicrobial Activity and Gas Chromatography-Mass Spectrometry (GC-MS) Analysis of Saudi Arabian Ocimum basilicum Leaves Extracts

Abstract

Recently, probiotic lactic acid bacteria have been utilized as therapeutic supplements and food additives. Nowadays, the interest has been increased regarding the commercial utilization of probiotic LAB strains isolated from traditional fermented food products. Therefore, the present study was aimed to investigate the probiotic properties of lactic acid bacteria isolated from traditional food sources viz. dosa batter and sauerkraut. Total 7 lactic acid bacteria were obtained, 4 from dosa batter and 3 from sauerkraut, out of which one isolate from each food source were selected based on their broadest antagonistic spectrum. These strains were identified using 16S r RNA technique as Lactobacillus plantarum DB-2 (isolated from dosa batter) and Lactobacillus plantarum SK-3 (isolated from sauerkraut). The investigation of acid-bile tolerance, antibiotic sensitivity, auto-aggregation, co-aggregation, bacterial adhesion to hydrocarbons were confirmed. The results revealed normal growth of L. plantarum DB-2 and L. plantarum sK-3 in the presence of low pH, high bile salt concentration and ability to produce antimicrobial compounds viz. bacteriocin and h 2 O 2 . No gelatinase, lipase and hemolytic activity were observed. Natural susceptibility to the tested antibiotics was investigated. Thus, according to these results, L. plantarum DB-2 and sK-3 proved the good probiotic candidates as they survived during stress conditions posing to them and can be exploited for the preparation of nutraceutical products. This study also revealed the potential of using LAB and /or bacteriocin produced by them as food bio preservative to control food borne pathogenic bacteria in near future.