Chemistry and cytotoxic activities of polyketides produced by the mangrove endophytic fungus Phomopsis SP. ZSU-H76

Abstract

A new polyketide, 2-(7′-hydroxyoxooctyl)-3-hydroxy-5-methoxybenzeneacetic acid ethyl ester (1), together with three known compounds dothiorelone A (2), B (3), and C (4) were isolated from the mangrove endophytic fungus Phomopsis sp. ZSU-H76 obtained from the South China Sea. Their structures were elucidated by spectroscopic methods, mainly 1D and 2D NMR spectroscopic techniques. Primary bioassays showed that 1 exhibited cytotoxicity against HEp-2 and HepG2 cells with IC 50 values of 25 and 30 μg/mL, respectively.Marine-derived fungi have proven to be a rich source of structurally unique and biologically active secondary metabolites [1]. In our search for new metabolites from marine-derived mangrove endophytic fungi from the South China Sea, we have isolated many significant new bioactive metabolites [2][3][4][5][6][7][8]. This paper reports the isolation and characterization of a new polyketide, 2-(7′-hydroxyoxooctyl)-3-hydroxy-5-methoxybenzeneacetic acid ethyl ester (1), and three known compounds dothiorelone A (2), B (3), and C (4) from the mangrove endophytic fungus Phomopsis sp. ZSU-H76 isolated from the stem of the mangrove tree Excoecaria agallocha from Dong Zai, Hainan, China. Cytotoxic effects of compound 1 against HEp-2 cells and HepG2 cells were first measured.The ethyl acetate extract of a fermentation broth of the fungus was repeatedly chromatographed on silica gel using gradient elution from petroleum to ethyl acetate to give compound 1 from the 15% ethyl acetate/petroleum fraction as a colorless oil. Compound

Chemical and molecular characterization of Phomopsis and Cytospora-like endophytes from different host plants in Brazil

“…Our results and previous reports (Brady et al 2000;Huang et al 2008Huang et al , 2009 showed that cytosporones, and possibly the related dothiorelones (Fig 2), are produced by members of Phomopsis, Cytospora, and Cytospora-like, although the distribution of these metabolites among different species in each genus is not known. No strain of chemotypes 2e5 was found to produce cytosporones or dothiorelones (Table 2).…”

“…are among the most commonly investigated endophytes (e.g. Huang et al 2008Huang et al , 2009Rukachaisirikul et al 2008;Yu et al 2008). We conducted a chemical investigation of a collection of Phomopsis spp.…”

Marine natural products

“…190 Pichia membranificiens [sponge, Halichondria okadai, (Izu Peninsula, Japan)] was the source of the indole derivatives 205 and 206, modest DPPH radical scavengers. 190 Pichia membranificiens [sponge, Halichondria okadai, (Izu Peninsula, Japan)] was the source of the indole derivatives 205 and 206, modest DPPH radical scavengers.…”

Isolation, Characterization and Anti-Multiple Drug Resistant (MDR) Bacterial Activity of Endophytic Fungi Isolated from the Mangrove Plant, <i>Aegiceras corniculatum</i>

“…In our present study, Alternaria was also found to be frequent genera (13.1%) and show no infectious symptom to its host. Phomopsis is an important mangrove endophyte, and many significant new bioactive metabolites were isolated from this fungus [7,9,19,20].…”