Characterization and application of Lipase 39-A from cryptococcus flavescens for cheese flavoring

Abstract

Yeast strain 39-A was isolated as a lipase producer from the digestive juice of Nepenthes ventricosa. The yeast was identified as Cryptococcus flavescens by morphological tests and comparative 26S rDNAD1/D2 and ITS-5.8S rDNA gene sequence analysis. The lipase from strain 39-A was purified from a culture filtrate by (NH4)2SO4 precipitation, and by chromatography with CM-Toyopearl 650M, Butyl- Toyopearl 650M, and Toyopearl HW-55. The purified enzyme appeared as a single band with 34 kDa on SDS-PAGE. The optimum temperature and pH were approximately 30°C and 7.0, respectively. The fatty acid specificity in milk triglyceride was similar to that of Lipase PGET, a pregastric esterase with shortchain fatty acid specificity in triglycerides. Lipase addition during the mozzarella cheese-making process produced a favorable cheese flavor. These results show that the lipase produced by C. flavescens 39-A has the potential to replace pregastric esterase in the dairy industry.