基于代谢组学分析不同收获期羊草营养品质变化

Analysis of nutrient quality changes of Leymus chinensis in different harvest periods based on metabolomics

为了探讨不同收获期羊草营养品质变化的机理,试验选取拔节期和枯黄期羊草,进行不同收获期羊草营养品质测定和代谢组学分析。结果表明:拔节期羊草的粗蛋白含量显著高于枯黄期(P<0.05),中性洗涤纤维和酸性洗涤纤维含量显著低于枯黄期(P<0.05);通过代谢组学分析共筛选到拔节期和枯黄期羊草差异代谢产物119种,其中64种代谢物表达量在枯黄期显著上调,而55种代谢物表达量在枯黄期显著下调。55种下调代谢产物中丙氨酸、谷氨酸、苯乙酰谷氨酰胺、嘌呤和嘧啶等蛋白质合成相关代谢物的表达水平显著下调,可能与枯黄期羊草粗蛋白含量下降有关;64种上调代谢产物中嘧啶和糖类的表达水平显著上调,可能与枯黄期羊草纤维类物质含量升高有关。说明拔节期间羊草的粗蛋白含量高,牧草品质好。

In order to explore the mechanism of nutritional quality change of Leymus chinensis in different harvest periods,this study took Leymus chinensis at jointing stage and late green stage as material to determine the nutritional quality of grass in different harvesting periods and analyzed it by metabolomics.The results showed that the crude protein content in the jointing stage was significantly higher than that in the late green stage(P<0.05),and the content of neutral detergent fiber and acid detergent fiber were significantly lower than that in the late green stage(P<0.05);through metabonomics analysis,119 differential metabolites of Leymus chinensis at jointing stage and late green stage were screened.64 metabolites in late green stage were significantly up-regulated,while 55 metabolites in late green stage were down-regulated.Among the 55 down-regulated metabolites,the expression levels of metabolites related to protein synthesis,such as alanine,glutamate,phenylglutamine,purine and pyrimidine,were significantly down-regulated,which might be related to the decrease of crude protein content in the late green stage.The expression levels of pyrimidines and sugars in the 64 up-regulated metabolites were significantly up-regulated,which might be related to the increase in the content of fiber in the late green stage.It indicated that the crude protein content of Leymus chinensis at late green stage was high,and the quality of forage was well.