Colletotrin: a sesquiterpene lactone from the endophytic fungus Colletotrichum gloeosporioides associated with Trichilia monadelpha

A new sesquiterpene lactone, namely colletotrin (1), together with two known fungal metabolites (2, 3), was obtained from a rice culture of Colletotrichum gloeosporioides, an endophytic fungus isolated from the stem bark of Cameroonian medicinal plant Trichilia monadelpha (Meliaceae). The structure of the new compound was established on the basis of extensive NMR analysis (1H, 13C, heteronuclear single-quantum coherence and heteronuclear multiple-bond correlation) completed by high-resolution electrospray ionization mass spectroscopy results and by comparison of these data with those of related compounds described in the literature. Their cytotoxic and antibacterial activities against the mouse lymphoma L5178Y cell line and Mycobacterium tuberculosis, respectively, were also evaluated. This study is the first report on the isolation of fungal metabolites from endophytic fungi associated with T. monadelpha (Meliaceae).

Ircinal E, a New Manzamine Derivative from the Indonesian Marine Sponge Acanthostrongylophora ingens

Chemical investigation of the MeOH extract of the sponge Acanthostrongylophora ingens afforded the new manzamine derivative ircinal E (1), in addition to six known metabolites (2–7). The structure of the new compound was unequivocally elucidated using one- and two-dimensional NMR spectroscopy, as well as high-resolution mass spectrometry. Compounds 1–6 exhibited strong to moderate cytotoxicity against the murine lymphoma L5178Y cell line with IC50 values ranging from 2.8 to 21.7 μM.

A New Cytotoxic Cytochalasin from the Endophytic Fungus Trichoderma harzianum

The new natural product 4′-hydroxy-deacetyl-18-deoxycytochalasin H (1), together with the known deacetyl-18-deoxycytochalasin H (2) and 18-deoxycytochalasin H (3) were obtained from the endophytic fungus Trichoderma harzianum isolated from leaves of Cola nitida. The structure of the new compound was unambiguously determined by 1D and 2D NMR spectroscopy, and by HRESIMS measurements, as well as by comparison with the literature. Compounds 1-3 showed potent cytotoxic activity against the murine lymphoma (L5178Y) cell line and against human ovarian cancer (A2780 sens and A2780 CisR) cell lines (IC50 0.19–6.97 μM). The A2780 cell lines included cisplatin-sensitive (sens) and -resistant (R) cells.