Microbial Diversity and Phylogeny Analysis of Buttermilk, a Fermented Milk Product, Employing 16S rRNA-Based Pyrosequencing

Abstract

Buttermilk is a traditional fermented dairy product popular in India and other Asian countries. In this study, the microbial population in a buttermilk sample was investigated by 16S rRNA gene-based bacterial tag-encoded FLX amplicon pyrosequencing (bTEFAP) approach. A total of 23,080 high-quality pyrosequencing reads was obtained. Of these, 96.3% of reads represented the well-defined domain bacteria and 3.7% represented unclassified domain; no archaeal sequences were found. Lactobacillus delbrueckii was the most predominant species identified, which constituted 94.86% of total reads. The other minor genera found included Streptococcus, Aeromonas, Methylobacter, Enterococcus, Micrococcus, Ralstonia, Moraxella, and Flavobacter. The buttermilk did not contain any pathogenic species. However, the roles of unclassifiable organisms are yet to be studied.

Keywords:

• microbial population
• bar-coded pyrosequencing
• buttermilk
• Lactobacillus

ACKNOWLEDGMENTS

Sathyanarayanan Jayashree acknowledges the University Grants Commission, New Delhi for providing financial support under Dr. D.S. Kothari Post-Doc Fellowship [No. F.4-2/2006 (BSR)/13-490/2011 (BSR)]. The authors also acknowledge UGC-CAS, UGC-CEGS, UGC-NRCBS, DBT-IPLS, and DST-PURSE programs at Madurai Kamaraj University.