PRESUMPTIVE INVOLVEMENT OF METHYL RICINOLEATE BETA-OXIDATION IN THE PRODUCTION OF GAMMA-DECALACTONE BY THE YEAST PICHIA-GUILLIERMONDII

Production of gamma-decalactone by yeasts from fatty acids has been re ported but little is known about the mechanisms involved in this proce ss. This paper provides information about the mechanisms involved in t he production of gamma-decalactone by Pichia guilliermondii in the pre sence of a fatty acid methyl ester. Culturing of P. guilliermondii in media containing methyl ricinoleate (12(R)-hydroxy-9(Z)-octadecenoic a cid) revealed a coordinated induction of beta-oxidation activities and gamma-decalactone production. However, no gamma-decalactone synthesis was noted when methyl ricinoleate was changed into methyloleate or me thyl linoleate, even though these fatty acid methyl esters are able to induce beta-oxidation activities in P. guilliermondii. These observat ions led us to conclude that methyl ricinoleate is an inducer of beta- oxidation and is probably the substrate for gamma-decalactone producti on. The fatty acid ester beta-oxidation should be involved, at least i n part, in this production.