Author(s): Praveen Dahiya | Sharmishtha Purkayastha
Journal: Journal of Biological Sciences
ISSN 1727-3048
Volume: 11;
Issue: 5;
Start page: 381;
Date: 2011;
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Keywords: tributyrin agar assay | production | Bacillus sp. PD-12 | extracellular lipase | screening | olive oil PVA emulsion | enzyme characterization
ABSTRACT
There is limited available information on the characterization of alkali-stable Bacillus sp. producing lipase and its commercial production. Therefore, thirty bacterial strains were isolated from oil industry soil samples and were screened for lipolytic activity. Bacillus sp. PD-12 was selected for lipase production because of its high lipolytic activity (4.2 IU mL-1). Bacillus sp. PD-12 lipase was optimally active at pH 8.0 and at 40C temperature. The lipase is capable of hydrolyzing vegetable oils and synthetic triglycerides. Maximum lipase production by Bacillus sp. PD-12 was obtained when grown under shaking conditions (250 rpm) at 30C for 24 h. In order to increase lipase production, optimization of carbon and nitrogen sources was studied. Maximum lipolytic activity (4.250.020 IU mL-1) was obtained with olive oil as a carbon source followed by coconut oil (2.50.030 IU mL-1). Among nitrogen sources, ammonium nitrate resulted in maximum lipolytic activity (15.60.036 IU mL-1). Lipase production by Bacillus sp. PD-12 was studied in a 3 liter fermentor with a working volume of 1.8 liter under optimized conditions resulted in lipolytic activity of 22 IU mL-1 after 21 h. Thus, short fermentation time (21 h) makes this fermentation system a promising one in terms of lipase productivity and alkali-stable Bacillus sp. can be used in detergent industry.
Journal: Journal of Biological Sciences
ISSN 1727-3048
Volume: 11;
Issue: 5;
Start page: 381;
Date: 2011;
VIEW PDF


Keywords: tributyrin agar assay | production | Bacillus sp. PD-12 | extracellular lipase | screening | olive oil PVA emulsion | enzyme characterization
ABSTRACT
There is limited available information on the characterization of alkali-stable Bacillus sp. producing lipase and its commercial production. Therefore, thirty bacterial strains were isolated from oil industry soil samples and were screened for lipolytic activity. Bacillus sp. PD-12 was selected for lipase production because of its high lipolytic activity (4.2 IU mL-1). Bacillus sp. PD-12 lipase was optimally active at pH 8.0 and at 40C temperature. The lipase is capable of hydrolyzing vegetable oils and synthetic triglycerides. Maximum lipase production by Bacillus sp. PD-12 was obtained when grown under shaking conditions (250 rpm) at 30C for 24 h. In order to increase lipase production, optimization of carbon and nitrogen sources was studied. Maximum lipolytic activity (4.250.020 IU mL-1) was obtained with olive oil as a carbon source followed by coconut oil (2.50.030 IU mL-1). Among nitrogen sources, ammonium nitrate resulted in maximum lipolytic activity (15.60.036 IU mL-1). Lipase production by Bacillus sp. PD-12 was studied in a 3 liter fermentor with a working volume of 1.8 liter under optimized conditions resulted in lipolytic activity of 22 IU mL-1 after 21 h. Thus, short fermentation time (21 h) makes this fermentation system a promising one in terms of lipase productivity and alkali-stable Bacillus sp. can be used in detergent industry.