五倍子对致病疫霉抑制作用活性成分研究

Study on Active Components of Galla chinensis against Phytophthora infestans (Mont.) de Bary

[目的]研究五倍子（Galla chinensis）提取物中对致病疫霉[Phytophthora infestans（Mont.）de Bary]有抑制作用的主要活性成分。[方法]运用石油醚、苯、95%乙醇、50%乙醇和25%乙醇对五倍子进行依次连续分步提取,并对各步所得提取物进行生物活性测定。[结果]3种不同浓度乙醇的提取物对致病疫霉游动孢子释放无显著差异,提取物浓度为100μg/ml时抑制率达55.95%~64.75%;而浓度为100μg/ml的苯和石油醚提取物的抑制率均在20.00%以下,显著低于乙醇提取物。将各浓度乙醇提取物合并,运用明胶沉淀法得到其中的单宁,浓度为100μg/ml时,单宁和非单宁成分对致病疫霉游动孢子释放的抑制率分别为50.63%和0.59%;同一剂量下五倍子单宁对致病疫霉菌丝生长的抑制作用强于对其游动孢子释放的抑制作用,其EC50分别为108.23、11.22μg/ml。[结论]该研究为更好地在有机马铃薯生产中开发利用五倍子防治晚疫病提供了科学依据。

[Objective] The research aimed to study the main fungicidal activity components of extracts of Galla chinensis against Phytophthora infestans（Mont.）de Bary.[Method] A continuous step by step extraction were carried out by means of series of solvents including petroleum ether,benzene,95% ethanol,50% ethanol and 25% ethanol,and then bioactivity of the different extracts against P.infestans were assayed.[Result] The results showed that 3 kinds of the ethanol extracts showed similar inhibitory effect to zoospores release of P.infestans,the inhibition rate reached 55.95%-64.75% with the concentration of 100 μg/ml.However,at the same concentration,the inhibition rate of petroleum ether and benzene extracts were no more than 20.00%,which was significantly lower than that of the ethanol extracts.Gallotannin was isolated from the mixture of those ethanol extracts with glutin,and the results of bioassay indicated that the inhibition rate of tannin and the non-tannin components to zoospores release of P.infestans were 50.63% and 0.59% respectively with the concentration of 100 μg/ml,which suggested that gallotannin were the main bioactive components for the inhibition to P.infestans in Galla chinensis.Gallotannin gave stronger inhibition to mycelium growth than sporangia germination of P.infestans with the same dosage,the EC50 were 108.23 and 11.22 μg/ml respectively.[Conclusion] The study can provide the scientific basis for better using Galla chinensis to prevent and control P.infestans in the production of organic potato.