title: Production and characterization of a mesophilic lipase isolated from Bacillus stearothermophilus AB-1.
abstract: Using Bacillus stearothermophilus AB-1 isolated from air, the production of lipase was attempted along with its purification and characterization studies. When different carbon and nitrogen sources were supplemented in the culture medium, xylose, tryptophan, alanine, phenylalanine and potassium nitrate were found to be the best. During cultivation, the strain secreted most of its lipase content after 48 h. In particular, the lipase produced in the culture broth showed 300 U mL(-1) when cultivated at optimal temperature and pH of 35 degrees C and 7.5, respectively. The enzyme was purified using 60% ammonium sulfate precipitation and sephadex G200 column chromatography. The enzyme was stable up to 40 degrees C and in the range of pH 7-8. This research reports for the first time the characterization of mesophilic lipase from Bacillus stearothermophilus AB-1 isolated from air.
authors.affiliation: Department of Botany and Microbiology, Faculty of Science, Helwan University, Ain Helwan, Cairo, Egypt.
authors.forename: Emad Abd El-Moniem
authors.initials: EA
authors.lastname: Abada
mesh_terms: D002244:Carbon / Q000494:pharmacology; D002845:Chromatography; D003470:Culture Media; D004795:Enzyme Stability / Q000187:drug effects; D001411:Geobacillus stearothermophilus / Q000187:drug effects / Q000201:enzymology*; D006863:Hydrogen-Ion Concentration; D008049:Lipase / Q000302:isolation & purification* / Q000378:metabolism*; D009584:Nitrogen / Q000494:pharmacology; D013696:Temperature
chemical_list: D003470:Culture Media; D002244:Carbon; D008049:Lipase; D009584:Nitrogen