National Dairy Research Institute

About: National Dairy Research Institute is a facility organization based out in Karnāl, Himachal Pradesh, India. It is known for research contribution in the topics: Population & Sperm. The organization has 3228 authors who have published 3524 publications receiving 51151 citations. The organization is also known as: Imperial Institute of Animal Husbandry and Dairying & Imperial Dairy Institute.

Antibacterial efficacy of nisin, pediocin 34 and enterocin FH99 against L. monocytogenes, E. faecium and E. faecalis and bacteriocin cross resistance and antibiotic susceptibility of their bacteriocin resistant variants

Abstract: The bacteriocin susceptibility of Listeria monocytogenes MTCC 657, Enterococcus faecium DSMZ 20477, E. faecium VRE, and E. faecalis ATCC 29212 and their corresponding bacteriocin resistant variants was assessed. The single and combined effect of nisin and pediocin 34 and enterocin FH99 bacteriocins produced by Pediococcus pentosaceus 34, and E. faecium FH99, respectively, was determined. Pediocin34 proved to be more effective in inhibiting L. monocytogenes MTCC 657. A greater antibacterial effect was observed against E. faecium DSMZ 20477 and E. faecium (VRE) when the a combination of nisin, pediocin 34 and enterocin FH99 were used whereas in case of L. monocytogenes MTCC 657 a combination of pediocin 34 and enterocin FH99 was more effective in reducing the survival of pathogen. Bacteriocin cross-resistance and the antibiotic susceptibility of wild type and their corresponding resistant variants were assessed and results showed that resistance to a bacteriocin may extend to other bacteriocins within the same class and also the acquired resistance to bacteriocins can modify the antibiotic susceptibility/resistance profile of the bacterial species used in the study. According to the hydrophobicity nisin resistant variant of L. monocytogenes was more hydrophobic (p < 0.001), whereas the pediocin 34 and enterocin FH99 resistant variants were less hydrophobic than the wild type strain. Nisin, pediocin 34 and enterocin FH99 resistant variants of E. faecium DSMZ 20477 and E. faecium VRE were less hydrophobic than their wild type counterparts. Nisin resistant E. faecalis ATCC 29212 was less hydrophobic than its wild type counterpart.

Evaluation of changes during storage of probiotic dahi at 7°C

Abstract: Low-fat probiotic dahi (an Indian traditional fermented milk product like yogurt) prepared with lactococci starter and two adjunct probiotic cultures of Lactobacillus acidophilus and Lactobacillus casei was stored at 7°C. The survival of bacterial species was affected during storage of dahi, in which viable counts increased up to 2 days and gradually decreased from 2 days, up to 8 days. The quality of refrigerated dahi was assessed by a panel of trained judges. On storage, pH significantly decreased over storage time, indicating that the dahi samples did not develop much acidity under the storage conditions of the study. However, after 8 days of storage, the samples were disliked by the panel, which reported slight bitterness, which may have been due to proteolysis. Proteolysis increased during storage. More a sl -casein was degraded than β-casein. On the basis of the results of this study we can conclude that dahi stored up to 8 days may be acceptable to consumers.