核桃炭疽病发生相关的酚类物质代谢分析

Metabolic Analysis of Phenolic Compounds Associated with Walnut Anthracnose

【目的】鉴定胶孢炭疽菌侵染核桃青皮后酚类物质种类以及变化规律,筛选潜在抗炭疽病有效成分,为探究核桃抵抗炭疽病发生机制提供参考。【方法】以‘香玲’和‘泰勒’2个品种核桃为试材,对其青皮体外接种胶孢炭疽菌,通过靶向代谢组学分析侵染后核桃青皮中酚类物质含量及相关变化。【结果】随着胶孢炭疽菌侵染天数增加,‘香玲’青皮病斑逐渐增大,在第6天发生明显变化,而‘泰勒’青皮病斑基本不变。‘香玲’和‘泰勒’青皮中酚类物质总量基本一致,划分为9大类,其中以原花青素/花青素、苯甲酸及其衍生物、黄酮醇和苯丙素类为主。‘香玲’中苯甲酸类最多,占60%以上,主要以没食子酸、丁香酸、鞣花酸和香草酸等为主;‘泰勒’中黄酮醇类最多,接近30%,主要以金丝桃苷、槲皮苷、扁蓄苷和杨梅苷等为主。炭疽菌侵染第6天,与‘香玲’相比,‘泰勒’青皮差异代谢物为60个,上调差异代谢物有52个,下调为8个,其中表儿茶素没食子酸酯、对香豆酸、原花青素B1/2/3、根皮苷、丁香酸、鞣花酸和阿魏酸等差异显著。分析炭疽菌侵染4~6天‘香玲’和‘泰勒’青皮差异代谢物发现,咖啡酸、柚皮素、(S)-圣草酚、扁蓄苷、槲皮苷和没食子酸6种物质出现明显变化,这可能与青皮病斑出现明显变化有关联。【结论】鉴定抗炭疽病品种‘泰勒’和感病品种‘香玲’130种酚类物质,代谢组学分析炭疽菌侵染后物质动态变化,筛选到原花青素B1/2/3、咖啡酸、柚皮素、(S)-圣草酚、扁蓄苷、槲皮苷和没食子酸等潜在抗炭疽病有效成分,可为后期开发炭疽病相关天然药物,探究炭疽病发生机制提供参考。

【Objective】This study aimed to provide references for exploring the mechanism of walnut resistance to anthracnose.For this end,we identified 130 phenolic compounds after the infection of Colletotrichum gloeosprioides into the walnut husk,carried out absolute quantification of the compounds,analyzed their changes,and screened the potential effective components against anthracnose.【Method】In this study,walnut(Juglans regia)cultivars,‘Xiangling’and‘Taile’,were used as the materials,and the walnut husk were inoculated with C.gloeosporioides,then the contents and related changes of phenolic compounds in walnut husk after infection were analyzed by targeted metabonomics.【Result】With the increase of days after infection of C.gloeosporioides,the plaques on‘Xiangling’husk gradually increased and changed significantly on the 6th day,while the plaques on‘Taile’husk remained basically unchanged.The total amount of phenolic compounds in‘Xiangling’and‘Taile’husk was basically the same.The compounds were divided into 9 categories,among which were mainly procyanidins/anthocyanins,benzoic acid derivatives,flavonols and phenylpropanoids.‘Xiangling’had the most benzoic acids,accounting for more than 60%,and they were mainly gallic acid,syringic acid,ellagic acid and vanillic acid.While‘Taile’contained the most flavonols,nearly 30%,and they were mainly hyperin,quercitrin,avicularin and myricetin.On the 6th day of anthracnose infection,comparing with‘Xiangling’,there were 60 different metabolites in‘Taile’,among which52 different metabolites were up-regulated and 8 different metabolites were down-regulated.Among them,epicatechin 3-O-gallate,4-Hydroxycinnamic acid,proanthocyanidin B1/2/3,phlorizin,syringic acid,ellagic acid and ferulic acid had significant differences.In addition,47 substances such askaempferol and m-coumaric acid were not detected.On analysis of the differential metabolites in the‘Xiangling’and‘Taile’husk infected for 4-6 days with anthracnose,it was found that 6 compounds of caffeic acid,naringenin,eriodictyol,avicularin,quercetin and gallic acid changedobviously,which might be related to the significant changes in husk plaques.【Conclusion】We have identified 130 phenolic compounds in the anthracnose resistant cultivar‘Taile’and the susceptible cultivar‘Xiangling’.Potential effective components against anthracnose,including proanthocyanidin B1/2/3,caffeic acid,naringenin,eriodictyol,avicularin,quercetin and gallic acid,have been screened by analyzing the dynamic changes of substances after anthracnose infection by using metabolomics.This study would provide references for the later development of anthracnose-related natural medicines and for exploring the mechanism of anthracnose.