Characterization and singlet oxygen quenching activity of (3R)-3-hydroxy-4-ketotorulene and (3R)-3-hydroxy-4-keto-γ-carotene isolated from the yeast Xanthophyllomyces dendrorhrous.

ABSTRACT

Structures of (3R)-3-hydroxy-4-ketotorulene (1) and (3R)-3-hydroxy-4-keto-γ-carotene (2) isolated from the yeast Xanthophyllomyces dendrorhrous were fully characterized by FAB MS, ¹H NMR, ¹³C NMR and CD spectroscopic data. Both 1 and 2 showed potent singlet oxygen (¹O2) quenching activity as that of astaxanthin and lycopene, which were well known strong ¹O2 quencher.