Cold-active α-amylases provided a large biotechnological potential and offers numerous economical and ecological benefits through energy saving process. It also minimizes undesirable chemical reactions that could occur at high temperatures. The objective of present study was to isolate novel bacterial strain for production of cold-active α-amylase. On the basis of primary screening thirty cold-active α-amylase producing bacteria were isolated from soil of Gangotri glacier, Western Himalaya, India. The isolated bacteria were subjected to enzyme production and one potential isolate (GA2) was selected for production optimization. The α-amylase production was found maximum (5870 units) at 20°C and pH 9 after 120 h incubation. Among the carbon and nitrogen sources, lactose (1%) and yeast extract (1%) was found best source, respectively. The isolate GA2 (Gangotri amylolytic) was resistant to penicillin (10 μg) among tested antibiotics and as per plasmid curing results, amylase production was a plasmid mediated characteristic. The phylogenetic analysis revealed that GA2 have highest homology with Microbacterium foliorum (99%). This was the first report on cold-active α-amylase production by M. foliorum GA2 and on the basis of 16S rRNA sequences also got an accession number HQ832574 from NCBI.
Roohi, M.Kuddus, I.Z. Ahmad and J.M. Arif, 2011. Production of Cold-active Extracellular α-Amylase by Newly Isolated Microbacterium foliorum GA2 from Gangotri glacier, Western Himalaya, India. Asian Journal of Biotechnology, 3: 449-459.