ORIGINAL PAPER
 
KEYWORDS
TOPICS
ABSTRACT
Yak (Bos grunniens) milk and its associated products are being used in high altitudes of Northern Pakistan. The aim of the study was to elucidate the diversity of lactic acid bacteria (LAB) isolated from raw yak milk. In total, 88 isolates were characterized according to their phenotypic, physiological and biochemical properties. The abundance of genera from the highest to the lowest was lactobacilli (56%) followed by enterococci (36%) and lactococci (8%). Among these isolates, 9 different species were recognized by studying their biochemical characterization with the use of API 50 CHL systems. The dominance of species included Lactobacillus paracasei subsp. tolerans (19%) followed by Lactobacillus plantarum and Enterococcus durans (17%), Enterococcus faecium (11%), Lactobacillus casei (9%), Enterococcus hirae and Lactococcus lactis (8%), Lactobacillus delbrueckii subsp. bulgaricus (7%) and Lactobacillus sakei (3%). Identification of 30 representative strains was further confirmed by 16S rRNA gene sequence analysis. So, a foundation for developing local starter cultures of LAB for the production of fermented products from yak milk is provided.
ACKNOWLEDGEMENTS
The authors are thankful for the financial support of the Higher Education Commission of Pakistan for the current research project under the HEC Indigenous 5000 PhD Fellowship Programme Phase II, Batch-I (PIN: 112-21766-2AVI-336).
CONFLICT OF INTEREST
The authors declare that there is no conflict of interest.
 
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ISSN:1230-1388