EFFECTS OF DETERGENTS ON ACTIVITY OF MICROBIAL LIPASES AS MEASURED BYTHE NITROPHENYL ALKANOATE ESTERS METHOD

Enzymatic activities of lipases from Chromobacterium viscosum, Pseudom onas fluorescens, Bacillus sp., Candida cylindracea, Aspergillus carne us, and Penicillium sp. were compared with the spectrophotometric p-ni trophenylbutyrate (pNB) assay at different concentrations of the deter gents Tween 20, Triton X-100, polyvinyl alcohol (LALLS), and linear al kylbenzene sulfonate (LAS). The activities of lipases from C. cylindra cea and C. viscosum were additionally measured with sodium desoxychola te (bile salt BL), hexadecyl trimethyl ammonium bromide (CTAB), and Tw een 80. The maximal activities of eukaryotic lipases were generally at the lower concentrations of detergents than those of prokaryotic lipa ses. All detergents, including the anionic detergent BL, inhibited euk aryotic lipases very effectively. LAS and CTAB stimulated C. viscosum lipase above their critical micellar concentrations (CMC), but CTAB di d not increase the activity of C. cylindracea lipase at all, although even a low concentration of LAS inhibited its activity. The other euka ryotic lipases behaved with LAS similarly to C. cylindracea lipase. It is more tedious to find proper detergent for eucaryotic than prokaryo tic lipase, because the detergents seem to stimulate eukaryotic lipase s in a very narrow range or low concentrations. Prolonged incubation w ith LAS decreased the activity of eukaryotic lipases effectively but p rokaryotic lipases only little. LALLS could be a good detergent for th e prokaryotic lipase reactions because it inhibited activity only a li ttle. The most significant observation was the high detergent toleranc e of Bacillus sp. lipase, it can be concluded that eukaryotic and prok aryotic lipases roughly Sor-m two separate classes behaving guile diff erently in different detergents. (C) 1998 Elsevier Science Inc.