摘要
Strain of Pseudomonas Lip35 producing lipase was isolated in a refrigerator. Lipase production and characterization of this strain were investigated under different conditions. The Pseudomonas was cultivated in shaking flasks in a fermentation medium in various nutritional and physical environments. Lipase production has been influenced by the presence of yeast-extract, soybean powder, NaCI, and Tween-80. Maximum lipase productivity was obtained when the physical environment of the fermentation medium was optimal for 67 h. The production of lipase reached 58.9 U·mL^-1. The lipase of Pseudomonas Lip35 can be considered to be inducible, but the inducer had little influence on the production of lipase. The lipase was characterized and showed high lipolytic activity from pH 7.5-8.0. The optimum temperature was observed at 20℃ and the thermal inactivation of lipase was obvious at 60℃. The lipase activity was inhibited by K＋, stimulated by Ca^2＋, and thermostability decreased in the presence of Ca^2＋, therefore the lipase was Ca^2＋ -dependent cold-adapted enzyme.
Strain of Pseudomonas Lip35 producing lipase was isolated in a refrigerator. Lipase production and characterization of this strain were investigated under different conditions. The Pseudomonas was cultivated in shaking flasks in a fermentation medium in various nutritional and physical environments. Lipase production has been influenced by the presence of yeast-extract, soybean powder, NaCI, and Tween-80. Maximum lipase productivity was obtained when the physical environment of the fermentation medium was optimal for 67 h. The production of lipase reached 58.9 U·mL^-1. The lipase of Pseudomonas Lip35 can be considered to be inducible, but the inducer had little influence on the production of lipase. The lipase was characterized and showed high lipolytic activity from pH 7.5-8.0. The optimum temperature was observed at 20℃ and the thermal inactivation of lipase was obvious at 60℃. The lipase activity was inhibited by K＋, stimulated by Ca^2＋, and thermostability decreased in the presence of Ca^2＋, therefore the lipase was Ca^2＋ -dependent cold-adapted enzyme.
基金
supported by the Major Program of the Hebei Province Commission of Science and Technology during the 11 th Five-Year-Plan period,China(06220106D)
