Isolation of a novel carotenoid, OH-chlorobactene glucoside hexadecanoate, and related rare carotenoids from rhodococcus sp. CIP and their antioxidative activities

Abstract

In the course of screening for antioxidative carotenoids from bacteria, we isolated and identified a novel carotenoid, OH-chlorobactene glucoside hexadecanoate (4), and rare carotenoids, OH-chlorobactene glucoside (1), OH-γ-carotene glucoside (2) and OH-4-keto-γ- carotene glucoside hexadecanoate (3) from Rhodococcus sp. CIP. The singlet oxygen ( 1O 2) quenching model of these carotenoids showed potent antioxidative activities IC 50 14.6μM for OH-chlorobactene glucoside hexadecanoate (4), 6.5μM for OH-chlorobactene glucoside (1), 9.9μM for OH-γ-carotene glucoside (2) and 7.3μM for OH-4-keto-γ-carotene glucoside hexadecanoate (3).