Isolation and characterization of an extracellular lipase from Mucor sp strain isolated from palm fruit

• Published in: Enzyme and microbial technology 2002-12, Vol.31 (7), p.968-975
• Main Authors: Abbas, Houria, Hiol, Abel, Deyris, Valerie, Comeau, Louis
• Format: Article
• Language: English
• Subjects: Biological and medical sciences; Enzyme characterization; Extracellular lipase; Fundamental and applied biological sciences. Psychology; Mucor sp; Palm fruit; Palm oil acidification; Purification
• ISSN: 0141-0229; 1879-0909
• DOI: 10.1016/S0141-0229(02)00190-4

During our screening of lipolytic fungus which may play a role in the acidification of palm oil, we have recently isolated a Mucor sp strain. Culture conditions were optimized and the highest lipase production amounting to 57 U/ml was achieved after 6 days of cultivation. The extracellular lipase was purified 1050-fold by ammonium sulfate precipitation, carboxymethyl–sephadex chromatography and Sephadex G75 gel filtration to a final specific activity of 6600 IU/mg. The molecular weight of the homogenous lipase was determined about 42 kDa by gel filtration and SDS–polyacrylamide gel electrophoresis. The purified lipase was determined as a glycoprotein with a pI of 6.2. The Nt sequence was determined as AspGluIleGluThrValGlyXPheThrMetAspLeuProProAsnProPro and showed no homology with the sequences of the known lipases suggesting that the enzyme may be a new lipase. The purified lipase hydrolyzed both synthetic and natural triglycerides with the optimal activity recorded on trioctanoin and sunflower oil, respectively. Its activity was strongly inhibited by Triton X-100 and SDS. Metal ions such as Fe 3+, Fe 2+ and Hg 2+ also decreased the lipase activity.