Secondary Metabolites Of EN-22, An Endophytic Fungus Derived From The Marine Polysiphonia Urceolata

Marine organisms produce a great deal of structurally unique and biologically active secondary metabolites due to their ocean living environment (such as high-salt, high-pressure, poor nutrition, low temperature), so they represent a rich source of natural products with anticipated biomedical potential. Marine derived fungi found in marine alga, marine animal, sediments, mangrove plants and even ocean floats, have been becoming a new focus of finding novel compounds with prominent activity and their chemistry and biology research have already provoked the interest of scientists around the world. In this paper, secondary metablites of EN22, an endophytic fungus derived from the red alga Polysiphonia urceolata, collected in Weizhou island of Chinese Guangxi province, was investigated.From the fermentation broth of EN22, an endophytic fungus derived from the red alga Polysiphonia urceolata, 26 compounds were isolated by the normal phase silica gel, Sephadex LH-20 column chromatography separation, the preparative thin layer chromatography (PTLC), as well as re-crystallization. Structures of the purified compounds were elucidated by analysis of spectroscopic data including IR,UV,MS,1D-NMR and 2D-NMR and by comparison to the literature of known structure. One compound was reported as a novel compound and two compounds was firstly reported as new natural product. These compounds are attributed to be eight indole derivatives, one quinoline derivatives, five steroids, one diketopiperazine derivative, one nucleoside derivative, one cerebroside derivative and one aromatic compound.Our research results have enriched the nature medicinal content of marine-derived fungus, and also provided considerable scientific proofs for their effective utilization.