Bioconversion of lutein using a microbial mixture--maximizing the production of tobacco aroma compounds by manipulation of culture medium.

The generation of aroma compounds by carotenoid cleavage in the 9-10 position was studied, due to the importance of these compounds in the flavor and fragrance industry. The bioconversion of the carotenoid lutein to C(13) norisoprenoids utilizing a microbial mixture composed of Trichosporon asahii and Paenibacillus amylolyticus was carried out by a fermentation process. Applying an experimental design methodology, the effects of nutritional factors on the production of aroma compounds present in the tobacco profile were studied. After an assessment of the significance of each nutritional factor, the levels of the variables yielding the maximum response were calculated. Glucose, tryptone, and yeast extract exerted a strong negative effect over the objective function, with glucose being the strongest. Lutein possessed a positive effect over the tobacco aroma production, while sodium chloride and trace elements showed no influence over the process. The yield attained after culture medium manipulation was almost ten-fold higher, compared with the base medium; and the aroma mixture was characterized as: 7,8-dihydro-beta-ionol (95.2%), 7,8-dihydro-beta-ionone (3.7%), and beta-ionone (1.1%).