Lipolytic activity of a new yeast strain Candida rugosa CMGB-CR6 isolated from oil-polluted soil

Yeast lipases present a growing interest for the synthesis of novel compounds and development of technologies with biotechnological applications. A new yeast strain CMGB-CR6 isolated from oilpolluted soil was identified as belonging to Candida rugosa using morphological observations, the API 20C AUX and Biolog Microbial ID systems and PCR-RFLP of the 5.8S rRNA-ITS and 18S rDNA-ITS. The analysis of eight RAPD profiles showed that the primer OPA03 is optimal for the discriminatory characterization of C. rugosa CMGB-CR6 compared to strains belonging to other Candida species and yeast genera. High lipolytic activity was determined even at low concentrations of Tween 80. Lipase production was induced by 1 % olive oil in combination with yeast extract, respectively, by 2.5 % Tween 80 in YNB medium, the nitrogen substrate representing a limitative factor. According to our observations, the dimorphic transition is a strain-specific process in Candida species. The correlation of present results with previous studies suggests that lipases from C. rugosa CMGB-CR6 could be related to its ability of assimilating n-alkanes and to synthesis of biosurfactants. This could represent an interesting basis for the development of methodologies that use hydrocarbons for lipase production in yeast cells.