| Torularhodin and torulene are two widespread microbial carotenoids with relatively few studies, as compared to other nutraceutical carotenoids such as β-carotene, lycopene and astaxanthin. Several genera of microorganisms produce it in high concentration (up to 0.1% of the cell dry weight), probably as a protection against photooxidation and free radicals. These pigments, which differ by a terminal carboxylic group, have provitamin-A activity and, being red, have potential use as food and cosmetic color additives. Several factors affect the biosynthesis of these substances, including: the composition of culture media, light irradiation, which may enhance the carotenoid production up to 25% of the non-irradiated cultures, and temperature, which changes the... |
