Produção de γ-decalactona por leveduras em batelada simples e batelada alimentada

Abstract

Lactones are compounds with sensory properties of great interest for food industries. Among lactones, γ-decalactone is the most used and it has a fruity peach aroma. In most biotechnological processes, castor oil, ricinoleic acid or its esters are used as a substrate for the synthesis of γ-decalactone by microorganisms. This compound is synthesized by microbial biotransformation on the peroxisomal β-oxidation pathway. Crude glycerol is the main by-product derived from the production of biodiesel and it is used as an alternative substrate for a variety of biotechnological applications, generating value-added products because of its wide availability and competitive cost. The objective of this study was to evaluate the best conditions for the production of yeast γ-decalactone. Crude glycerol and castor oil in different concentrations (10, 20 and 30%) were evaluated as substrate, in simple batch and fed-batch. After that first stage, the influence of pH and agitation were evaluated on the growth and production of γ-decalactone from yeasts Yarrowia lipolytica CCMA 0242 and Lindnera saturnus CCMA 0243. Y. lipolytica CCMA 0242 showed better results in the culture supplemented with 30% castor oil. There was no difference in the tested fermentation processes. The growth of yeast Y. lipolytica CCMA 0242 was also higher when inoculated into the medium with castor oil. Agitation and pH did not affect the production of aroma by yeasts. Production of γ-decalactone by yeast L. saturnus CCMA 0243 was 97,5% greater than the Y. lipolytica CCMA 0242.The population of yeast L. saturnus CES-Y677 UFLA obtained a higher growth when was agitated at high speed (200 rpm). In the evaluated conditions, 30% castor oil showed the best results for the production of γ-decalactone. Yeast Lindnera saturnus CCMA 0243 produced considerable amounts of γ-decalactone.