Secondary Metabolites Of Two Marine Algous Endophytic Fungi And Their Bioactivities

Endophytic fungi of algae are one of the important sources of lead compounds, living in coastal environment which is different from land environment, under high pressure, high salinity, tidal variation. Biosynthetic pathways of them are distinct from biosynthetic pathways of terrestrial organism, and they have great potential in the production of compounds with novel structures and bioactivity.In this paper, endophutic fungi, Talaromyces sp. and Aspergillus nomius, were fermented, respectively. (11S)-3,4-dihydro-2-(α-hydroxybenzyl)-3-methyl-4-oxoquinazoline(1) and (11R)-3,4-dihydro-2-(α-hydroxybenzyl)-3-methyl-4-oxoquinazoline(2), roquefortine C(3), Z-roquefortine C(4), viridicatol(5), penitrem A(6), penijanthine A(7), paspaline(8), and 3-deoxo-4b-deoxypaxilline(9), stigmasta-4-ene-3-one(10), ergosterol peroxide(11), dehydroergosterol(12) were isolated from the extract of Talaromyces sp., and ergosterol peroxide(13), (24R)-24-methylcholest-4,22-dien-3-one(14), stigmasta-4,22-dien-3-one(15), stigmasta-4-ene-3-one(16), (22E,24R)-ergosta-7,22-dien-3β,5α,6β-triol(17), 4-(hydroxymethyl)-5-hydroxy-2H-pyran-2-one(18), (5-hydroxy-2-oxo-2H-pyran-4-yl) methyl acetate(19), demethylsterigmatocystin(20) were isolated from the extract of Aspergillus nomius. Compound 1 and compound 2 are enantiomer, and both of them are new natural products. The bioassay results of inhibiting brine shrimp, anti-bacteria (Escherichia coli, Staphylococcus aureus) and anti-fungi (Colletotrichum lagenarium, Staphylococcus aureus) showed that compound 6 and compound 20 were more toxic to brine shrimp than the others and compounds 4-7 and compound 20 could inhibit Staphylococcus aureus. LCso of compound 6 and compound 20 were 3.1 mg/L and 0.02 mg/L.