Identification and Bioactivity of Compounds from the Mangrove Endophytic Fungus Alternaria sp.

Abstract

Racemic new cyclohexenone and cyclopentenone derivatives, (±)-(4R*,5S*,6S*)-3-amino-4,5,6-trihydroxy-2-methoxy-5-methyl-2-cyclohexen-1-one (1) and (±)-(4S*,5S*)-2,4,5-trihydroxy-3-methoxy-4-methoxycarbonyl-5-methyl-2-cyclopenten-1-one (2), and two new xanthone derivatives 4-chloro-1,5-dihydroxy-3-hydroxymethyl-6-methoxycarbonyl-xanthen-9-one (3) and 2,8-dimethoxy-1,6-dimethoxycarbonyl-xanthen-9-one (4), along with one known compound, fischexanthone (5), were isolated from the culture of the mangrove endophytic fungus Alternaria sp. R6. The structures of these compounds were elucidated by analysis of their MS (Mass), one and two dimensional NMR (nuclear magnetic resonance) spectroscopic data. Compounds 1 and 2 exhibited potent ABTS [2,2′-azino-bis(3-ethylbenzthiazoline-6-sulphonic acid)] scavenging activities with EC50 values of 8.19 ± 0.15 and 16.09 ± 0.01 μM, respectively. In comparison to Triadimefon, compounds 2 and 3 exhibited inhibitory activities against Fusarium graminearum with minimal inhibitory concentration (MIC) values of 215.52 and 107.14 μM, respectively, and compound 3 exhibited antifungal activity against Calletotrichum musae with MIC value of 214.29 μM.

Identification and Antifungal Activity of Compounds from the Mangrove Endophytic Fungus Aspergillus clavatus R7

“…They were obtained from the College of Agriculture, South China Agricultural University. The antifungal activities of the isolated compounds were determined by the broth dilution method as described in the previous report to get the minimum inhibitory concentration (MIC) [ 21 ]. Triadimefon and the solvent were used as positive and negative control, respectively.…”

Bioactive Chaetoglobosins from the Mangrove Endophytic Fungus Penicillium chrysogenum

“…Cytotoxicity activities of the compounds against three human tumor cell lines, including a human breast cancer cell line (MDA-MB-435), a human gastric cancer cell line (SGC-7901), and a human lung adenocarcinoma epithelial cell line (A549) were tested by MTT method, as described in a previous report [25]. Epirubicin was used as the positive control.…”

“…Gray, known as a semi-mangrove medicinal plant, is a small evergreen shrub distributed along the coastal regions of several Asian counties [23]. As part of our ongoing search for biologically active and/or structurally novel metabolites of the endophytic fungi from Myoporum bontioides [24,25], the fungus Penicillium chrysogenum (collection No. V11) harbored inside the normal vein attracted our interests due to its antifungal activity exhibited by the methanol extract in vitro.…”

Fusarihexins A and B: Novel Cyclic Hexadepsipeptides from the Mangrove Endophytic Fungus Fusarium sp. R5 with Antifungal Activities

“…The antifungal activities of compounds 1, 2, and 3 were tested against three phytopathogenic fungi obtained from the College of Agriculture, South China Agricultural University: C. gloeosporioides, C. musae, and F. oxysporum. MIC was determined by the twofold broth dilution method as previously described [39]. A stock solution of each test sample was prepared in 5 % (v/v) DMSO/H 2 O, following which 0.5 mL of the solution was serially diluted with 0.5 mL of potato dextrose broth (PDB) (Shanghai Ruichu Biotech.…”