The genus Algoriphagus comprises a group of red-colored,Gram-negative,aerobic bacteria that inhabit various marine environments.Several species of Algoriphagus produce the keto-monocyclic carotenoid flexixanthin;howev...The genus Algoriphagus comprises a group of red-colored,Gram-negative,aerobic bacteria that inhabit various marine environments.Several species of Algoriphagus produce the keto-monocyclic carotenoid flexixanthin;however,information on its derivatives and their biological activities is limited.In this study,Algoriphagus sp.strain Fs4 was isolated from the surface of seaweed collected at Nanaehama,Hokkaido,Japan.Based on structural analysis via nuclear magnetic resonance spectroscopy,of the carotenoid produced by the strain,it was identified as 2′-hydroxyflexixanthin,a new carotenoid in the genus Algoriphagus.A comparison of the carotenoid profiles of 25 species of Algoriphagus bacteria revealed that flexixanthin was present in all strains,and some strains also produced 2-or 2′-hydroxyflexixanthin.The biological activities of flexixanthin and its derivatives were evaluated in terms of their antioxidant and anti-inflammatory effects against macrophages.The degree of inhibitory effect on lipid peroxidation was in the order:2-hydroxyflexixanthin>2′-hydroxyflexixanthin>flexixanthin.Conversely,flexixanthin significantly inhibited lipopolysaccharide-induced interleukin-1βand-6,and nitric oxide synthase 2 mRNA expression,demonstrating a stronger inhibitory effect than that of 2′-hydroxyflexixanthin;2-hydroxyflexixanthin showed no significant inhibitory effects.These results indicate that the introduction of hydroxyl groups at specific sites affects the antioxidant and anti-inflammatory activities of flexixanthin.The findings of this study highlights the potential of the genus Algoriphagus as a source of flexix-anthin and its derivatives and provides a basis for the future application of these monocyclic carotenoids in the production of nutraceuticals and pharmaceuticals.展开更多
基金supported by JSPS KAKENHI(21H02276 and 23K14018)and J-PEAKS.
文摘The genus Algoriphagus comprises a group of red-colored,Gram-negative,aerobic bacteria that inhabit various marine environments.Several species of Algoriphagus produce the keto-monocyclic carotenoid flexixanthin;however,information on its derivatives and their biological activities is limited.In this study,Algoriphagus sp.strain Fs4 was isolated from the surface of seaweed collected at Nanaehama,Hokkaido,Japan.Based on structural analysis via nuclear magnetic resonance spectroscopy,of the carotenoid produced by the strain,it was identified as 2′-hydroxyflexixanthin,a new carotenoid in the genus Algoriphagus.A comparison of the carotenoid profiles of 25 species of Algoriphagus bacteria revealed that flexixanthin was present in all strains,and some strains also produced 2-or 2′-hydroxyflexixanthin.The biological activities of flexixanthin and its derivatives were evaluated in terms of their antioxidant and anti-inflammatory effects against macrophages.The degree of inhibitory effect on lipid peroxidation was in the order:2-hydroxyflexixanthin>2′-hydroxyflexixanthin>flexixanthin.Conversely,flexixanthin significantly inhibited lipopolysaccharide-induced interleukin-1βand-6,and nitric oxide synthase 2 mRNA expression,demonstrating a stronger inhibitory effect than that of 2′-hydroxyflexixanthin;2-hydroxyflexixanthin showed no significant inhibitory effects.These results indicate that the introduction of hydroxyl groups at specific sites affects the antioxidant and anti-inflammatory activities of flexixanthin.The findings of this study highlights the potential of the genus Algoriphagus as a source of flexix-anthin and its derivatives and provides a basis for the future application of these monocyclic carotenoids in the production of nutraceuticals and pharmaceuticals.