A NEW STRAIN OF RHODOTORULA-RUBRA ISOLATED FROM YOGURT

A new strain of Rhodotorula rubra has been isolated from yogurt which shows promise as a source for pigment and protein feed for aquacultured animals. The pigment was extracted by rupturing the cells with the French press followed by extraction with acetone and purification of the acetone extract using petroleum ether and cold 10% NaCl. The absorption spectrum indicated that the pigment was a carotenoid, the chemistry of which was examined using nuclear magnetic resonance, mass spectroscopy and resonance Raman spectroscopy. A reverse-phase HPLC equipped with octadecylsilylated (ODS) silica column showed nearly 80-times more pigment production under similar cultural conditions than Phaffia rhodozyma. The isolate grows optimally at 20-degrees-C when grown on a variety of media. Its morphology has been studied using transmission electron microscopy, scanning electron microscopy and phase contrast microscopy. From the results of the API system, the isolate was identified as Rhodotorula rubra.