New Sorbicillinoids with Tea Pathogenic Fungus Inhibitory Effect from Marine-Derived Fungus Hypocrea jecorina H8.

Four new dimeric sorbicillinoids ( 1 - 3 and 5 ) and a new monomeric sorbicillinoid ( 4 ) as well as six known analogs ( 6 - 11 ) were purified from the fungal strain Hypocrea jecorina H8, which was obtained from mangrove sediment, and showed potent inhibitory activity against the tea pathogenic fungus Pestalotiopsis theae ( P. theae ). The planar structures of 1 - 5 were assigned by analyses of their UV, IR, HR-ESI-MS, and NMR spectroscopic data. All the compounds were evaluated for growth inhibition of tea pathogenic fungus P. theae . Compounds 5 , 6 , 8 , 9 , and 10 exhibited more potent inhibitory activities compared with the positive control hexaconazole with an ED 50 of 24.25 ± 1.57 µg/mL. The ED 50 values of compounds 5 , 6 , 8 , 9 , and 10 were 9.13 ± 1.25, 2.04 ± 1.24, 18.22 ± 1.29, 1.83 ± 1.37, and 4.68 ± 1.44 µg/mL, respectively. Additionally, the effects of these compounds on zebrafish embryo development were also evaluated. Except for compounds 5 and 8 , which imparted toxic effects on zebrafish even at 0.625 μM, the other isolated compounds did not exhibit significant toxicity to zebrafish eggs, embryos, or larvae. Taken together, sorbicillinoid derivatives ( 6 , 9 , and 10 ) from H. jecorina H8 displayed low toxicity and high anti-tea pathogenic fungus potential.