Abstract :
Lipase producing microorganisms were isolated using tributyrin agar plate from
different oil contaminated sites like petrol pumps, temple, kitchen waste dumping sites, etc. The plates were observed for zone of hydrolysis and C/Z ratio for each isolate was determined. The C/Z ratio of isolate C4 followed by U7 and K31 were the lowest and thus indicate larger clear zone as compared to colony. Potential lipase producing isolates were further screened for their
solvent tolerance ability. Among them only seven isolates (C2, C3, C4, C7, K25, K31, and K35) were able to grow in the presence of organic solvents and also showed zone of hydrolysis on tributyrin agar in presence of organic solvents. The bacterial isolate K31was showed maximum growth in presence of almost all the organic solvents followed by K25 and K35 isolates. The aim of isolating a broad range organic solvent tolerant microorganism was fulfilled by isolate K31. The isolate K31 gave the highest activity with isopropanol (2.26±.15 U) at a solvent: media ratio of 1:3. The isolate K31 has also shown significant lipase activity with coconut oil (2.33±0.12 U) followed by olive oil (2±0.1 U), groundnut oil (1.76±0.14), soya oil (1.73±0.1).
Keyword :
Lipase, Tributyrin, Organic solvent tolerant microorganisms