Utilization of agro-industrial wastes for the production of lipase from Stenotrophomonas maltophilia isolated from Arctic and optimization of physical parameters

• A potential cold tolerant lipase producer Stenotrophomonas maltophilia was isolated from Arctic sediment.
• Lipase was successfully produced on agro-industrial wastes groundnut cake, coconut cake, neem cake, wheat bran and rice bran and ground nut was found to be superior substrate for lipase production.
• Temperature, pH, and moisture content were optimized for all substrates tested.
• Enzyme concentrated by acetone precipitation was purified to 2.9 fold by DEAE-Cellulose.
• Molecular weight of the purified lipase was found to be 49.1 KDa.

In the present work production of lipase by Arctic sediment isolate Stenotrophomonas maltophilia was investigated, and focus was on the lipase production using agro industrial waste. Optimization of physical parameters which enhance the lipase production in agricultural waste such as groundnut cake, rice bran, wheat bran, neem cake, and coconut cake was achieved and significance was validated by ANOVA. The crude lipase was concentrated by precipitation with acetone and further purification was carried out by ion exchange chromatography followed by SDS-PAGE. When screened for extracellular lipase production, 54 isolates showed positive results and significant activity was expressed by sediment isolate KS 46 which was phylogenetically identified to be S. maltophilia. The groundnut cake supported maximum enzyme production (74.117 U/ml) followed by coconut cake (61.911 U/ml), neem cake (58.737 U/ml), wheat bran (49.614 U/ml) and rice bran (28.165 U/ml). Characterization of the enzyme revealed the optimum temperature to be 28 °C and optimum pH to be 6 for groundnut cake, neem cake and coconut cake while pH 7 for rice bran and wheat bran. Maximum lipase production was attained at 60% moisture for all substrates except for neem cake (70%). The enzyme was purified to 2.9 fold and molecular weight was found to be 49.1 KDa. The results suggest that agro wastes such as groundnut cake has the potential to be used as alternative cost effective substrate for lipase production and optimum conditions vary for the same enzyme when different substrates are utilized.