Journal of Pure and Applied MicrobiologyVol. 11 No. 3

Production of Lipases by Certain Thermo Tolerant Bacteria

Ghaidaa Jihadi Mohammed

Department of Biology/College of Science/University of Al-Qadisiyah, Iraq.

Received on 10 June 2017 and accepted on 30 August 2017

 

ABSTRACT

Lipases are hydrolytic enzymes which hydrolyse triglycerides to free fatty acids and glycerol. Bacterial lipase producers were isolated from certain loamy arid soils. Eight thermotolerant bacteria able to produce lipases were identified down to their species level. Identification studies have revealed that 5 isolates were belonging to Bacillus stearothermophilus, while the others were belonging to B. megaterium; B. licheniformis and B. subtilis. The impact of the incubation period ,medium pH, temperature , the source of carbon for the lipase production was detected. Results have shown that the optimal conditions for Lipases production by most of these bacteria were incubation temperature of 50C, incubation period of 72 hours, pH 7.0, presence of 0.1% yeast extract, and when sucrose plus tributyrin were supplied as carbon sources. Production of lipases by the used heat resistant bacteria could be of academic and applied importance especially for manufacture of detergents.

Keywords : Lipase, Thermotolerant bacteria, Loamy arid soils.