Abstract: Taking Heterosigma akashiwo and Prorocenrum micans as test materials, the algicidal activity of Spartina anglica against the growth of the two har
mful microalgae were investigated, with the algicidal compounds isolated and identified. Lower concentration S. anglica stimulated the growth of H. akashiwo, while high concentration S. anglica inhibited the H. akashiwo growth significantly. The lethal concentration of S. anglicafresh tissue, dry p
owder, and extracts to H. akashiwowas 4.8 mg·ml^-1, 0.8 mg·ml^-1, and 0.5 mg·ml^-1, respectively. All test concentration S. anglica had obvious inhibitory effects on the growth of P. micans, and the lethal concentration of S. anglica fresh material, dry powder, and extracts was 9.6 mg·ml^-1, 1.6 mg·ml^-1, and 1.25 mg·ml^-1, respectively. Two algicidal compounds in S. anglicawere isolated, and identified as isohamnetin-3-O-sophoroside-7-O-rhamnoside and syringetin-3-O-galactoside.

Key words: Spartina anglica, Heterosigma akashiwo, Prorocenrum micans, algicidal activity, algicidal compounds, savoy, light quality, chlorophyll, photosynthetic characteristics, nutritional quality.