EFFECT OF MEDIA AND PROCESS PARAMETERS IN THE ENHANCEMENT OF EXTRACELLULAR LIPASE PRODUCTION BY BACTERIAL ISOLATES FROM INDUSTRIAL EFFLUENTS

The present investigation was carried out to evaluate the effect of different growth conditions on lipase production by different bacterial isolates. The extracellular lipase producing bacteria Bacillus sp., Serratia sp. Pseudomonas sp. and Staphylococcus sp. were isolated from industrial effluents. Optimization of physical and chemical parameters was done for maximum lipase production using these isolates and mixed culture (consortia). Growth of the organisms and lipase production were measured with varying pH (4-10), incubation temperature (4-60°C), incubation time (15-72 hrs.), carbon source, nitrogen source, different inducers and metal ions. Enhanced lipase production for most of the isolates was observed at 35°C, pH 7 and after 45 hrs. of incubation. Glycerol, soy meal and starch were observed as effective carbon sources and casein, peptone and tryptone as effective nitrogen sources for lipase production. Among the metal ions Ca2+ showed good lipase production with all the isolates and with consortia and the substrates Pongemia oil and Neem oil were observed as good inducers for lipase production. In the present study consortia showed an increased lipase content in comparison to individual isolates under all the optimized conditions.