Carotenoid profiles of yeasts belonging to the genera Rhodotorula, Rhodosporidium, Sporobolomyces, and Sporidiobolus

Eighteen yeast species of the genera Rhodotorula, Rhodosporidium, Sporobolomyces, and Sporidiobolus, each one represented by its type strain, were investigated with the objective of evaluating their carotenoid composition. The pigments were extracted from yeast cells, quantified by high pressure liquid chromatography diode array detector and the main compounds were confirmed by atmospheric pressure chemical ionization quadrupole mass spectrometry. Significant (P < 0.01) differences among several species and (or) genera were observed. Thirteen strains were seen to be able to produce carotenoids, from 16.4 to 184 mu g/g cell dry mass and from 6.0 to 1993.4 mu g/L culture. The main carotenoids produced were identified as torularhodin, torulene, gamma-carotene, and P-carotene. The correlation matrix calculated on the basis of the carotenoid composition data matrix indicated significant (P < 0.01) relationships between torulene and torularhodin (r = 0.81), gamma-carotene and torulene (r = 0.49), beta-carotene and torulene (r = -0.72), as well as P-carotene and gamma-carotene (r = 0.64). These significant correlation coefficients may suggest that species belonging to the genera Rhodosporidium, Sporobolomyces, and Sporidiobolus possess a carotenoid biosynthetic pathway analogous to that elsewhere postulated for Rhodotorula species.