Studies On Fungicidal Constituents And Derivative Synthesis Of Dictamnus Dasycarpus Turcz

The fungicidal activity of Dictamnus dasycarpus Turcz was studied by a systematic way in vitro and pot test with Alternaria longipes, Curvulavia lunata, Valsa mali, Fulvia fulva, Macrophoma kawatsukai, Staphylococcus aureus, Bacillus subtilis, Blumeria guaminis. The results are as follows:1. The bioassay result indicated that the optimal solvent extracting active component was petroleum ether. It also showed that the petroleum ether extract could markedly inhibit hypha growth of five pathogens, their inhibition ratio are all more than 70% at the concentration of 1000ug/mL. The result of pot test indicated that the protective effect and therapeutic effect of the petroleum ether extract against the Blumeria guaminis were 63.38% and 31.41% at the concentration of 1000ug/mL.2. After repeatedly open column chromatography, WML-1 and WML-2 were obtained from petroleum extract of Dictamnus dasycarpus Turcz with bioactivity-guided. Comparing with the standard spectra of chromatography chart such as MS, 1HNMR and 13CNMR, WML-1 and WML-2 were identified respectively as fraxinellone and dictamnine. The result of spore germination proved that the value of EC50 of WML-1 and WML-2 against Alternaria longipes and Curvulavia lunata were 123.28,46.61ug/mL and 64.20,91.72ug/mL respectively.3. The reduced products of WML-1by KBH4 were WML-3 and WML-4. Comparing with the standard spectra of chromatography chart such as MS, 1HNMR and 13CNMR, WML-3 was identified as 8-α-dihydrogen fraxinellone, WML-4 was complex, one of them is 8-β-dihydrogen fraxinellone. The result of spore germination proved that the value of EC50 of WML-3 and WML-4 against Alternaria longipes and Curvulavia lunata were 81.06,69.87ug/mL and 101.52,66.23ug/mL respectively.