Abstract: In this study, a lipase-producing strain, named as xjA, was isolated from soil near Riyuexing oil factory in Daqing. The solid-state fermentation conditions for lipase production by the strain were optimized using one-factor-at-a-time and orthogonal array design methods. Meanwhile, the prepared lipase was used to synthesize conjugated linoleic acid glyceride. The results indicated that the optimal fermentation conditions were wheat bran/soybean meal mass ratio of 1:4, culture medium/adding water volume ratio of 1:1, fermentation temperature of 29 ℃, inoculation amount of 0.3%, and fermentation time of 3 days. Under these conditions, the activity of lipase was up to 1450 U/g. The load rate of conjugated linoleic acid (CLA) in the conjugated linoleic acid glyceride synthesized using the obtained lipase was 13.6%.

Key words: lipase, solid-state fermentation, lipase activity, conjugated linoleic acid glyceride