Diapolycopenedioic acid xylosyl esters A, B, and C, novel antioxidative glyco-C30-carotenoic acids produced by a new marine bacterium Rubritalea squalenifaciens

Novel acyl glyco-carotenoic acids, diapolycopenedioic acid xylosyl esters A, B, and C, were isolated as red pigments by using chromatographic methods from a marine bacterium, Rubritalea squalenifaciens, belonging to subdivision 1 of Verrucomicrobia. The structures of these diapolycopenedioic acid xylosyl esters were determined to be 4-[2-O-acyl-beta-D-xylopyranosyl] hydrogen 4,4'-diapo-Psi,Psi-carotene-4,4'-dioate by spectroscopic analysis. Diapolycopenedioic acid xylosyl ester A showed potent antioxidative activity in a (1)O(2) suppression model.