Biotransformations catalyzed by lipases from spore-forming microorganisms

ABDULHAMID, MARÍA BELÉN; COSTAS, LUCIANA; BAIGORI, MARIO DOMINGO; CASTRO, GUILLERMO RAÚL; PERA, LICIA MARÍA

Puerto Madryn

Congreso; 46 th Annual Meeting SAIB; 2010

It is generally accepted that lipase-catalyzed hydrolytic activity does not always correlate with its esterification or transesterification activity. Therefore, the selection of a proper lipase for a given application is required. Thus, the aim of this study was to investigate the reactivity of 64 lipases from spore-forming microorganisms towards hydrolytic and transesterification reactions by using p-nitrophenyl palmitate as a chromogenic acyl donor substrate. Specific hydrolytic activities were not highly correlated with the corresponding specific transesterification activities using ethanol (r=-0.113, P=0.375), starch (r=0.226, P=0.073), low-methoxyl (LM) pectin (r=0.622, P<0.001) and high-methoxyl (HM) pectin (r=0.533, P<0.001) as acyl acceptor. The highest specific hydrolytic activity (52.73±1.68 U/mg) was exhibited by lipase from strain 5. Lipases from strains 30, 47 M, 5 and Brevibacillus agri E12 gave the highest transesterification activities in the presence of ethanol (26.36±2.55 U/mg), starch (0.31±0.04 U/mg), LM pectin (1.25±0.22 U/mg) and HM pectin (3.12±0.56 U/mg), respectively. Under our assay conditions, no hydrolytic activity was detected with lipase from strain 30