| Summary: | Two yeasts: Cryptococcus uchicensis TMY9 and Pichia uchicensis TMY10 and one fungus Verticillium tingalensis TMFMB are described for the first time as lipase producer microorganisms. The strains have been isolated after an ecological screening in a palm oil industry. The yeasts- C. uchicensis and Pichia uchicensis - mainly produce extracellular lipases as active as those produced by traditional lipase producing microorganisms. The extracellular lipases are active in the hydrolysis of crude palm oil and its industrial derivatives. Contrarily in the isolated fungus, the lipase mainly remains bonded to biomass. In all cases, greater hydrolytic activities are observed in the hydrolysis of palm olein and super-olein than with saturated substrates as stearine. P. uchicensis lipase shows moderated selectivity versus saturated acid triglycerides compared to substrates with high proportion of oleic acid (olein or superolein). The opposite behavior is observed with C. uchicensis and fungal lipases. P. uchicensis produces a more active crude lipase than C. uchicensis with lower biomass production. The kinetic runs performed with crude yeast lipases suggest a three steps mechanism where the high penetration of lipase in the fat gouts favors the hydrolysis.
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