Study On The Metabolites From The Endophytic Fungi Of Ceriops Tagal And Their Activity

Endophytic fungus is a important resource for natural bioactive compounds, and searching and using the resource has been one of hot subjects. Magrove is a particular plant grow in tropical and subtropical coast intertidal, which has plentiful endophytic fungi, that has been the second large group in the marine fungi. Magrove fungi have attracted much attention because of their unique environment and a variety of secondary metabolites, then raise a high passion to seach. At the period, many antibiotic compounds have been isolated from magrove endophytic fungi, which have been a important resource for marine drug. The unique environment gave birth to the unique metabolic mechanisms, so the natural products from the magrove endophytic fungi of secondary metabolites always possess novel structure. At the same time, magrove endophytic fungi have a infinite potential for the marine drug because of the novel compounds often have well and widely bioactivity such as antibacterial, cytotoxin activity, a-glucosidase inhibitory activity and so on.Ceriops tagal is a plant of Rhizophoraceae of Ceriops, and that as a medicinal plant in Hainan, possessed many bioactivity. From now, many bioactive compounds haved been found from the endophytic fungus of magrove in the south china sea. But, about the researching of the Ceriops tagal is very rare. In order to obtain more new antibiotic compounds from magrove fungus,95strains isolated from the roots, stems and leaves of magrove Ceriops tagal. The aim strain is chosed by the methods of TLC and bioactivity. Then J54and J6were chose as two predominant strains from the95strains by screened using TLC and biological activity tests with the fermentation product of the fungus. The last, the fungi of J54and J6were studied further for their secondary metabolites about chemical composition and biological activity, also the strains identification and metabolic pathway.The secondary metabolites of J54and J6were isolated and purified by chromatography, and their structures were identified by physicochemical and spectral data (MS, IR, UV,1D-and2D-NMR so on). Then, their biological activity (antibacterial, cytotoxin activity, a-glucosidase inhibitory activity) was tested at the end.Sixteen compounds were isolated from the PDA liquid fermentation product of endohytic fungi J54, their structures were determined as lyratols H-O (1-8)? aervecdysteriod D (9), pteleifoside C (10),3-methoxyepicoccone (11),4,6-dihydroxy-2,3,5-trimethylbenzaldehyde (12), mycosphine B (13), mycosphine A (14),5-hydroxymethylfurfural (15), and4-hydroxyphenethyl alcohol (16). Compounds1-8were a series of new sesquiterpenoids.Seven compounds were isolated from the rice fermentation product of endophytic fungi J6, which were were determined as thermolides (17-21), rigidiusculamide C (22), citreoisocoumarin (23). All compounds1-7were isolated from the endophytic fungus for the first time.All compounds were tested for their biological activity. The result showed that1and11exhibited cytotoxincity against K-562with IC50=90.1?M and52.2?M,2possessed modest inhibitory effect on Staphylococcus aureus (S. aureus) with the diameter of the inhibition zone9.4mm,4and23showed inhibitory effect on Candida albicans (C. albicans) with the diameter of the inhibition zone21.8mm and11.2mm,6exhibited significant in vitro a-glucosidase inhibitory activity with the IC50vaule of2.27mM.