Secondary Metabolites Of Three Marine Fungi And Their Biological Activities

In recent years,it has become more and more difficult to find new active natural products from terrestrial microorganisms.There is an urgent need for natural products with novel structures as the leading compounds in the development of new drugs.Therefore,people pay more attention to the rich resources from the sea,and more and more work on marine natural products has been done.In this study,62 compounds,including 14 new compounds,were isolated from three marine-derived fungi,and some them were preliminarily screened for their bioactivities.As our investigation on the secondary metabolites of Penicillium pinophilum SCAU037 isolated from the root of a mangrove plant Rhizophora stylosa on the Techeng Isle,China.,a total of 29 compounds were obtained and identified,including pinophilones A-E(1a/1b and 2-4),dihydrovermistatin(5),vermistatin(6),penisimplicissin(7),2"-epihydroxydihydrovermistatin(8),5'-O-methyldihy-drovermistatin(9),methoxyvermistatin(10),hydroxyvermistatin(11),6-demethylvermistatin(12),6-demethylpenisimplicissin(13),3-O-methylfunicone(14),penicidone D(15),penicidone C(16),isopenicillide(17),penicillide(18),3'-O-methyldehydroisopenicillide(19),pinophilin G(20),pinophilin B(21),Sch725680(22),(+)-mitorubrinic acid B(23),deoxyfunicone(24),cyclo(D)-trans-4-OH-Pro-(D)-Phe(25),cyclo-(4-hydroxyprolinyl)-leucine(26),chaetomone A(27)and clearanol A(28).Among these compounds,1a/1b and 2-4 were identified as new compounds.Our investigation on the secondary metabolites of Aspergillus terreus SCAU011 isolated from the root of a mangrove plant Rhizophora stylosa on the Techeng Isle,China,led to a total of 27 compounds isolated and identified,including(8''S,9'')-dihydroxy-dihydrobutyrolactone I(29),asperbutenolide A(30),7"S-methoxy-butyrolactone IV(31),7"R-methoxy-butyrolactone IV(32)butyrolactone X(33),4"-hydroxy-butyroscavin(34),butyrolactone XI(35),(E)-4-(5-methoxy-5-oxopent-2-en-2-yl)benzoic acid(36),novobenzomalvin D(37),aspernolide B(38),7"R-methoxy-8"S-hydroxy-aspernolide E(39),butyrolactone III(40),aspernolide E(41),terrein(42),p-formylphenol(43),asperlide A(44),butyrolactone IV(45),(+)-3',3''-di-(dimethylallyl)-butyrolactone II(46),versicolactone B(47),3-hydroxy-5-(4-hydroxybenzyl)-4-(4-hydroxyphenyl)furan-2(5H)-one(48),butyrolactone I(49),butyrolactone II(50),cytochalasin B(51),questin(52),methyl-3,4,5-trimethoxyl-2-[2-(nicotinamide)benzamido] benzoate(53),terrusnolide A(54),and alteamide(55).Among them,29-37 were identified as new compounds.In order to investigate the secondary metabolites of Trichoderma citrinoviride SCAU084 isolated from Guaishi sea beach in Guang Xi province,a total of 3 compounds were isolated and identified,including ergosta-4,6,8(14),22-tetraen-3-one(56),WF-3681 Methyl Ester(57),and WF-3681(58).The activities of the isolated compounds were tested for their antibacterial,antioxidant,anti-acetylcholinesterase,?-glucosidase or COX-2 inhibition effect.The results showed that,compounds 22,30,35,38,41,46,49 and 54 exhibited inhibitory effect against Staphylococcus aureus and compounds 30 and 46 showed certain antibacterial activity against Bacillus subtilis and Vibrio Splendidus;compounds 16,18,22,30,35,46,44-49 and 51 possessed inhibitory activities against ?-glucosidase,while 16,22,30,46 and 48 displayed significantly better effect than the positive control acarbose;compounds 29-31,33-34,39-41,44-46 and 48-50 had antioxidant activity,while compounds 44 and 48 were significantly more active than positive control curcumin,with IC50 values of 1.4 and 0.7 ?M,respectively;compounds 29-33,35-37,39-40,44-45 and 48-50 was observed inhibitory activity against COX-2 at 20nM.