Screening Of Lipase Producing Strains And Studing On Properties Of Lipase

Lipases are a class of enzymes which catalyse the hydrolysis of long chain triglycerides. Microbial lipases are currently receiving much attention with the rapid development of enzyme technology. Lipases constitute the most important group of biocatalysts for biotechnological applications. Oily soil samples were collected. About 80 strains producing lipase were isolated. By studying the enzymatic characteristics of 9 strains highly producing lipase, then choose the strain 060805 for further study.The strain 060805 is identified as Brevundimonas by 16s rDNA sequence analyse and characterister of physiology and biochemistry, then named as Brevundimonas sp. 060805.Studying on the effects of nitrogen sources, carbon sources and other influence factors has optimized the lipase fermentation conditions for the strain. The optimal nitrogen source is tryptone, the optimal carbon source is glucose, the optimal condition for lipase producing are inoculation for 1.5%, initial pH7.0, clutivated aerobically at 28℃with an aeration rate of 200rpm for 48 hours. Then a maximum yield of 23.64u/ml was obtained.By studying the enzymatic characteristics, the optimum temperature and pH for it were 35℃and 6.0. The enzyme activity was stable after incubated in the temperature range from 30-60℃for 60min.