荠菜提取液对烟草青枯病菌的抑制作用

采用无菌水、乙酸乙酯、无水乙醇、石油醚、丙酮、甲醇浸提荠菜干粉,通过室内毒力试验,分别考察荠菜提取液对烟草青枯病菌的抑制作用,结果仅有乙酸乙酯和无菌水荠菜提取液对烟草青枯病菌有抑菌活性,乙酸乙酯提取液抑菌率最高,为63.9%,无菌水提取液抑菌率为28.9%。通过透射电镜、麦法兰分度计比浊法、蒽酮比色法、考马斯亮蓝法分别考察荠菜无菌水和乙酸乙酯提取液对烟草青枯病菌形态、生长曲线、糖利用率及蛋白质含量的影响。电镜观察表明,经荠菜无菌水和乙酸乙酯提取液处理的烟草青枯病菌细胞膜和细胞壁的结构发生变化,菌体裂解。荠菜乙酸乙酯和水提取液能使烟草青枯病菌对数期滞后,糖利用能力降低,蛋白质含量增高。

Inhibition activity of Capsella bursa-pastoris extracts against Ralstonia solanacearum

Water, ethyl acetate, anhydrous ethanol and petroleum ether, acetone, methanol were used to extract Capsella bursa-pastoris powder, the inhibitory effects of 6 kinds of solvent extracts on Ralstonia solanacearum were investigated through indoor virulence test , the results showed that only ethyl acetate and water extracts from Capsella bursa-pastoris had antimicrobial activity on Ralstonia solanacearum , the of ethyl acetate extract reached 63.9%, and antibacterial rate of water extract was 28.9%. The influences of water and ethyl acetate extracts on morphology, growth curve,utilization rate of sugar and protein content of Ralstonia solanacearum were investigated by transmission electron microscopy (SEM), wheat flange dividing turbidimetry, anthrone colorimetry, coomassie brilliant blue method .Electron microscopy showed that the structures of cell membrane and cell wall were changed and the bacteria cracked in Ralstonia solanacearum treated with water extract and ethyl acetate extract from Capsella bursa-pastorisof . Ethyl acetate extract and water extract from Capsella bursa-pastoris can make Ralstonia solanacearum logarithmic phase lag, reduce sugar utilization, and increase protein content in Ralstonia solanacearum.