Abstract

STUDY OF PROTEOLYSIS BY Macrococcus luteus ISOLATED FROM REFRIGERATED MILK

Syed Nisar Ahmed*

ABSTRACT

Psychrotrophic bacteria such as Staphylococcus spp., Pseudomonas spp., Enterobacter spp., Bacillus spp., Acinetobacter spp., Alcaligenes spp., Aeromonas spp., Vibrio spp., Flavobacterium spp., Micrococcus spp. and Achromobacter spp. have been extensively isolated from milk and dairy products Mitchell et al., (1985). The psychrotrophic bacteria may have direct as well as an indirect effect on the quality of milk and dairy products (Bishop et al., 1994). Study of enzymes from cold-adapted microorganisms may provide novel ways of understanding thermo biochemistry as well as lead to possible applications of such enzymes in the processing of food and the biotransformation of chemicals at low temperature. In this present work psychrotrophic bacteria Macrococcus luteus BSoC1 was isolated from sour curd sample obtained from Bharat milk dairy, Aurangabad, (MH), India. Molecular identification was done by 16S rRNA sequencing, partial sequence was submitted to NCBI GeneBank database and received accession number (MW412933). Proteolytic activity of Macrococcus luteus BSoC1 was carried out. Bacterium showed maximum proteolytic activity as a selection ratio of 5.3 at 200C and 4.5 at 70C. Similarly Selection Ratio (S: R value) at different pH was measured as maximum 5.3 at pH 7 in optimum temperature conditions.

Keywords: Psychrotroph, Macrococcus luteus, selection ratio, proteolytic, wash performance.