Antioxidant and antibacterial effects of carotenoids extracted from rhodotorula glutinis strains

Abstract

In this study, carotenoids extracted from the yeast twenty different Rhodotorula glutinis strains (M1-M47) isolated from soil, plant, pine and tree leaves, grape, aubergine, pee, parsley and carrot were studied for their antibacterial and antioxidant activity. Carotenoid contents of Rhodotorula glutinis strains changed between 0.23 to 1.23 mg L-1. Most of the carotenoids extracted from Rhodotorula glutinis strains (sixteen out of twenty) showed both antioxidant and antibacterial effects. Carotenoids extracted from Rhodotorula glutinis strains No. 2, 25, 26 did not show any antimicrobial activity and strains No. 1, 33 and 41 did not show any antioxidant effect. Strain No. M38 (0.74 mg L-1) was not effective neither as antibacterial nor antioxidant. The results strongly suggested that the potential utility of carotenoid synthesizing yeast Rhodotorula spp as an alternative source of natural preservatives (antioxidant and antimicrobial), carotenoid pigments (colourants) and nutraceuticals.