title: Production, purification and characterization of Bacillus lipase.
abstract: The lipolytic activities in the supernatant fractions of Bacillus cereus and Bacillus coagulans cultures were investigated. Aeration, agitation, different media, emulsified oils, inoculum size and phase of growth affected lipase production. Aeration was essential for lipase production (air: medium ration 4:1) and produced the highest activity. The lipolytic activity reached a maximum level after incubation for two days with continuous agitation. It was also elevated by the presence of either olive oil or tributyrin and with lesser extent in the presence of castor oil. The enzyme levels were drastically reduced in the presence of animal fat, cotton seed oil, margarine or glycerol. The extracellular lipase enzyme from Bacillus cereus was purified with 46.2% overall recovery thought too steps, an acetone precipitation of the whole supernatant and purification by gel filtration on sephadex G-100. The efficiency of the purification process was evaluated through the polyacrylamide gel electrophoresis. The enzyme has an optimum pH 7.5 at the optimum incubation temperature of 40 degrees C. It is stable and retains its full activity after heating at 40-50 degrees C for 30 min. The activity is lost completely at 80 degrees C.
authors.affiliation: Microbial Chemistry Department, National Research Centre, Dokki, Cairo, Egypt.
authors.forename: H A
authors.initials: HA
authors.lastname: el-Shafei
authors.forename: L A
authors.initials: LA
authors.lastname: Rezkallah
mesh_terms: D000388:Air; D001407:Bacillus / Q000201:enzymology*; D001409:Bacillus cereus / Q000201:enzymology; D003470:Culture Media; D004795:Enzyme Stability; D005947:Glucose; D007218:Industrial Microbiology; D008049:Lipase / Q000302:isolation & purification*; D009821:Oils; D012441:Saccharomyces cerevisiae; D012641:Selection, Genetic
chemical_list: D003470:Culture Media; D009821:Oils; D008049:Lipase; D005947:Glucose