from indigenous fermented foods and human gut ... - Thapar University

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Chapter IV: Results
belonging to the genus Lactobacillus. These isolates were subcultured in order to obtain pure
isolates and furthur characterized for their morphology by microscopy and gram staining.
4.2 Morphological and Biochemical Characterization of Lactobacilli
Ninety six strains were isolated on MRS medium from different samples of traditionally
fermented food and identified as Lactobacillus spp. by Gram staining. All the bacterial
isolated (LAM, LKH, HKTand T) found to be short, smooth, convex, single or paired square
bacilli, Gram positive and formed opaque creamy colony without any pigmentation
The colony morphology on MRS agar was off white, rod, with smooth edges and
raised from center. All of the isolated Lactobacillus spp. were Gram positive rod with
arrangement of singles cells to clusters for Lactobacillus spp. LAM-1, LAM-2, LAM-5,
LAM-18, while Lactobacillus spp. LKH-2, LKH-3 and LKH-5 were found in single or in
pairs. Lactobacillus spp. LAM-1 and LAM-2 were isolated from pickled mango, while
Lactobacillus spp. LKH-2, LKH-3 and LKH-5 were isolated from Kharoli and Bhaati jaanr
samples respectively (Table 4.1).
None of the isolates were able to ferment sorbitol, maltose and arabinose.
Lactobacillus spp. LKH-2, LKH-3 and LKH-5 were able to ferment galactose but didn’t
fermented raffinose and a smiliar result of fermentation was obtanied for Lactobacillus spp.
LAM-1 and LAM-2. All the isolates showed negative catalase activity (Table 4.1and 4.2).
Phenotypic, genotypic identification and in vitro probiotics properties were carried out only
for the cultures, having ability to survive in detectable numbers upon successive passage
through solutions mimicking saliva, gastric juice and intestinal juice.