Study On Secondary Metablites From Endophytic Fungi Pestalotiopsis Karstenii And Isaria Cateinannulata And Their Bioactivities

The chemical constituents of two endophytic fungi, the fermentation broth of Pestalotiopsis karstenii and Isaria cateinannulata, were investigated and reported in this essay. Twenty compounds, including two new ones, were isolated from these two endophytic fungi by using various chromatographic methods (silica gel column chromatography, preparative thin-layer chromatography, gel chromato-graphy and preparative HPLC). The structures of these compounds were elucidated by extensive spectroscopic analysis (1D and2D-NMR、MS、IR、UV etc.).Ten compounds were obtained from the fermentation broth of the strain Pestalotiopsis karstenii, each of which was first isolated in this fungi. Four sterides were isolated from this genus and named as:Ergosta-4,7,22-dien-3β-ol(1), Ergosta-4,7,22-trien-3-one (2),5α,8a-Epidioxy-(22E,24R)-ergosta-6,22-dien-3β-ol(3),(22E,24R)-Ergosta-7,22-dien-3β,5a,6β-triol (4) respectively. Four lactone were isolated in this strain which were named as: LL-P880a(5), LL-P880β(6), Pestalrone A (7), Pestalrone B (8), compounds7and8were two new ones. In addition, there were still two Benzene derivatives which were isolated in this fungi and named as4-Hydroxybenzaldehyde(9) and4-Hydroxybenzoic acid(10).Ten compounds were obtained from the fermentation broth of the strain Isaria cateinannulata, including three fatty acids and their derivatives, named as9-Hydroxyheptadecanoic acid(11), Hexadecanoic acid(12) and Trilinolein(13). Three phthalate easter were isolated and named as:Bis(2,5-dimethylhexyl) ester(14), Diisobutyl phthalate(15) and Dibutyl phthalate(16). Two macrocyclic lactone compounds were isolated in this fungi which were named as:Cephalosporolide E(17) and Cephalosporolide F(18) separatedely. One pigment was isolated and named as nidulalin A(19).The four lactone which were isolated from the fermentation broth of the strain P. Karstenii were tested using the MTT method. The result showed that LL-P880β(6) exhibited significant activities agains Hela, HepG2, U251with IC50values of12.6,31.7, and4μg/mL respectively. Pestalrone A (7) and Pestalrone B (8) showed activities agains U251with IC50values of2.4and12.0μg/mL, respectively.