EFFECT OF NITROGEN SOURCES ON GROWTH AND PIGMENTATION OF RHODOTORULA RUBRA IN SUBMERGED CULTURE.

Carotenoids pigments are of great interest to many areas because of their wide distribution in nature and their benefits for health. Rhodotorula rubra produces carotenoid pigments when growing in submerged cultures containing sugars, nitrogen sources, growth factors and salts. Among the carotenoid pigments, this yeast synthesizes small quantities of torularhodin, the only pigment with antioxidant properties. The influence of carbon and nitrogen sources on composition of carotenoid mixture in culture media is significant. The Rhodotorula rubra strain was grown in shaken, submerged cultures on appropiate medium with different nitrogen sources: NaNO₃, Ca(NO₃)₂, (NH₄)₂C₆H₆O₇, (NH₄)₂SO₄, NH₄Cl. The daily values of absorbance, pH, total soluble solids in culture media were recorded and the carotenoid pigments were extracted in acetone, n-hexane and alkaline methanol. [ABSTRACT FROM AUTHOR]