The Autofluorescent Substance in the Posterior Flagellum of Swarmers of the Brown Alga Scytosiphon lomentaria

Abstract

Abstract The flagellar autofluorescent substance of the brown alga Scytosiphon lomentaria , which is probably involved in the photoreception of the phototaxis of flagellate cells, was investi­ gated. 4′,5′-Cyclic FMN (1) was isolated from the extract of whole mature plants for the first time as a natural product. Since the concentration of 4′,5′-cyclic FMN (1) was considerably low in vegetative plants, which do not contain fluorescent flagella, this substance is consid­ered to correspond to the flagellar fluorescent substance.