Preliminary Study On The Bioactive Compounds From Metabolites Of Two Marine-Derived Fungi

This thesis covers preliminary study on the anti-Rhabditis sp., anti-brine shrimps and AChE inhibitory activity of 188 marine-derived fungi. Furthermore, we studied the metabolites of two marine-derived fungi, #229 and C-3-5-9.We tested the anti-Rhabditis sp. for crude extracts of 188 fungi. The result is metabolites of marine-derived fungi are toxic against Rhabditis sp.. At the concentration of 0.5mg/mL, the virulence of grade A accounts for 1.60% of the total strains. The strains which lead to up 50% mortality account for 43.1%. By second screening, the crude extract of #164 is most active against Rhabditis sp.. At the concentration of 0.5mg/mL, the mortality is up to 96.67% after treating for 24h. We tested the anti-brine shrimps for crude extracts of 188 fungi. The crude extract of #122 is most active. At the concentration of 0.5mg/mL, the mortality is 100% after treating for 2h. Furthermore, the crude extracts of #13,#45,#83,#123,#305 are toxic against brine shrimps. At the concentration of 0.5mg/mL, the mortalities are all above 85% after treating for 24h.We studied the relationship between concentrations of crude extracts and anti-brine shrimps for the above 6 fungi. The crude extract of #305 is most active against brine shrimps. At the concentration of 0.1mg/mL, the mortality is 90% after treating for 24h. Its LC50 is only 75μg/mL.Among the 188 crude extracts, the crude extracts of #229 and #170 are most active against AChE. Their IC50s are respectively 30μg/mL and 25μg/mL. But further study showed the two fungi are possibly the same strain. The TLC result of the crude extracts from the two fungi is the same.We studied the metabolites of #229 fungus under the guidance of bioactive direction. We isolated an active AChE inhibitor, territrem B. Furthermore, we also isolated an antifungal compound, palitantin with its MIC value against Candida albicans 62.5μg/mL.The crude extract of C-3-5-9 fungus exhibited antifungal, antibacterial and anti-brine shrimp activities. We isolated two cytotoxitic compounds, gliotoxin and...