基于氨基酸特征的荞麦Fisher判别

The Fisher Discrimination of Buckwheat Based on the Amino Acids Characteristics

根据甜荞和苦荞氨基酸的特点,筛选有效判别指标,建立判别准则。分别以氨基酸质量分数和相对含量为指标,采用逐步法构建Fisher判别模型,并进行试验验证。采用质量分数法建立的判别模型,以组氨酸、谷氨酸、丝氨酸、甘氨酸、苏氨酸和酪氨酸为变量,回判正确率为94.71%,交互验证正确率为93.27%;采用相对含量法建立的判别模型,以组氨酸、谷氨酸、甘氨酸、丝氨酸、苏氨酸和丙氨酸的相对含量为变量,回判和交互验证正确率均为95.19%;采用12份荞麦材料对模型进行试验验证正确率为100%。组氨酸、谷氨酸、甘氨酸、丝氨酸、苏氨酸的质量分数和相对含量在荞麦判别中均发挥重要作用,氨基酸指标与判别分析技术相结合,可作为荞麦种类鉴别和质量控制的一种有效、可行的方法。

According to the amino acid characteristics of common buckwheat and tartary buckwheat, this paper screened effective discrimination indexes and established a discrimination criterion. The mass fraction and relative content of amino acids were taken as indexes to establish a fisher discrimination model through stepwise method and verify the model. In the discrimination model established by the mass frastion method, the accuracy of discrimination was 94.71% and the accuracy of cross - validated was 93.27 % taking histidine, glutamic, serine, glyeine, threonine and tyrosine as variables. In the discrimination model, which was established through the relative content method with the relative content of histidine, glutamic, serine, glycine, threonine and alanine for variables, the accuracy of discrimination was 95.19% and the accuracy of cross - validated was also 95.19%. The accuracy of the model adopting 12 buckwheat samples was 100%. The mass fraction and the relative content of histidine, glutamic, serine, glycine and threonine played an important role in the discrimination of buckwheat. The combination of amino acid index and modern statistical techniques should be a useful and feasible method for the discrimination and quality control of buckwheat.