Extraction And Separation Of Antifouling Active Substances In Ulva Pertusa

Marine fouling organisms are organisms which attach and grow on the surface of underwater facilities and ships, include animals, plants and microorganisms. Huge loss was caused by biofouling all over the world each year. Therefore, measures must be taken to control fouling organisms. Antifouling paint is the most effective way to protect the ship from biofouling. As we all know, in the traditional antifouling paints, toxic antifouling agents such as DDT and organic tin, are often used. But those biocides not only cause serious pollution on the marine environment, but also affect human health. Therefore, the research on novel environment-friendly marine antifouling materials has become hot.There is an important ways to screen antifouling active materials from the natural products. Ulva pertusa is common large-scale algae plant along the coast of Yellow Sea, China, which prevents its surface from other fouling organismthrough some mechanism. . In this paper, the antifouling compounds were isolated and extracted from Ulva Pertusa. through chemical methods.The extracts of Ulva pertusa were obtained by two methods, UPAFS-A and B. The antifouling activity was evaluated by bioassays with diatom. When the inhibition rate was 90%, the concentration of UPAFS-A is lower than B at 0.5mg/ml. so, UPAFS-A was selected for the next experiment.Extract UPAFS-A was isolated by silica gel column chromatography, with eluting by petroleum ether, ethyl acetate, ethanol, mixed solvent of ethanol:water (2:1). Six fractions were collected, and named as UPAFS-A1 , UPAFS-A2, UPAFS-A3, UPAFS-A4, UPAFS-A5 and UPAFS-A6. The bioassays indicated thatthe fraction A5 was the most effective substance to inhibite the growth of diatom and reattachment of mussel. The inhibition rate to diatom was more than 90% at the concentration of 0.5mg/ml. There was no mussel to reattach at the concentration of 0.6mg/ml.Fraction UPAFS-A5 was isolated by through silica gel column chromatography, with eluting by ethyl acetate: ethanol (1:19) and ethanol:water (2:1). Four productions were obtained and named as UPAFS-A51, UPAFS-A52, UPAFS-A53 and UPAFS-A54. The bioassays indicated that production UPAFS-A52 was the most effective compound in the four productions. The inhibition rate to diatom was more than 95%at the concentration of 0.3mg/ml, and there was, no diatom growth on the suface of glass plate at the concentration of 0.8~1.0mg/ml. The reattachment of mussels was completely inhibition at the concentration of 0.3mg/ml.Production UPAFS-A52 was separated by high performance liquid chromatography, and the elution was methyl cyanide:water in gradient transformation. .of the weight was analysed by LC-MS, and nine compounds were identified with the following molecular weight: 244.0, 399, 339.3, 441, 452.4, 565.5, 678.5, 791.6 and 904.7.In this paper, antifouling compounds were extracted from Ulva pertusa, and the antifouling activity was tested by bioassays with diatom and mussel.. In the future, research will conduct to more bioassays with other fouling organisms, and molecular structure analysis.