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bioRxiv · 10.64898/2026.01.09.698673

Genetic diversity of Lactobacillus delbrueckii in home-made Dahi from different regions of India as revealed by genotyping-by-sequencing

Tripathi, P.·Singh, V. K.·Tiwari, M.·Tripathi, S. B.
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Abstract

Microbial diversity of bacterial species in home-made curd from different states of India was analyzed using genotyping-by-sequencing. The most prevalent species were Lactobacillus delbrueckii subsp. bulgaricus, Lactobacillus helveticus, Streptococcus thermophilus and Lactobacillus kefiranofaciens. Pathogenic species such as Salmonella enterica serovar Typhimurium and Shigella dysenteriae were found in over 60% of samples. High intraspecific variation was observed in Acinetobacter baumannii, Bacillus cereus, Enterococcus faecium, Escherichia coli, Lactococcus lactis subsp. cremoris, Lactococcus piscium, Salmonella enterica serovar Typhimurium and Shigella dysenteriae. Intra-specific genetic relatedness in Lactobacillus delbrueckii subsp. bulgaricus in curd samples largely correlated with their respective sites of collection. Research HighlightsO_LIMetagenomic DNA from home-made Dahi (curd) samples from various states in India were used for GBS-SNPs C_LIO_LIGBS-SNPs were able to resolve within-species variability across the samples. C_LIO_LIMajority of the samples contained both probiotic as well as potential pathogenic bacteria. C_LIO_LISeveral of curd samples contained multiple strains. C_LI

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Tripathi, P., Singh, V. K., Tiwari, M., Tripathi, S. B.. 2026-01-09. Genetic diversity of Lactobacillus delbrueckii in home-made Dahi from different regions of India as revealed by genotyping-by-sequencing. https://doi.org/10.64898/2026.01.09.698673

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