Commercially acceptable concentrations (0.02%) of butylated hydroxytolulene (BHT), butylated hydroxyanisole (BHA), tertiary butylhydroxyquinone (TBHQ), Tenox 4, and Tenox 8 were evaluated for their effect on the lipolytic activity of mixed Pseudomonas crude lipases (MCLs). MCLs were prepared from lipases produced by raw milk isolates of Pseudomonas fluorescens, P. cepacia, and P. putida. GRAS antioxidants, 1-ascorbyl 6-palmitate (AP) and d-α-tocopherol (AT), at 0.5, 1.0, and 2.0% concentrations, were also evaluated for their effect on lipase activity. Antioxidants and enzyme preparations were incubated for 30 min at 25 or 40°C. At 25°C, all antioxidants tested inhibited lipase activity to some extent. At 2% concentration, AP completely (100%) inhibited lipolytic activity, and AT inhibited lipolytic activity by 89%. At 40°C, the effectiveness of AP and AT as lipolytic inhibitors decreased, and the low concentrations of BHT, BHA, TBHQ, Tenox 4, and Tenox 8 stimulated lipolytic activity.
Published as Paper No. 8948. Journal Series Nebraska Agricultural Experiment Station, Lincoln, NE 68583-0919.