基于色度原理对薏苡仁不同饮片的判别研究

Discrimination of Different Semen Coicis Decoction Pieces Based on Chromaticity Principle

目的:拟建立快速区分生薏苡仁、麸炒薏苡仁及法薏苡仁的客观量化判别方法,为薏苡仁不同饮片的工艺规范化研究及质量标准制定提供科学依据,为其他中药不同炮制品的区分提供参考。方法:采用分光光度测色仪测定生薏苡仁、麸炒薏苡仁及法薏苡仁粉末色度值L^(*)、a^(*)、b^(*),计算E^(*)ab,统计分析薏苡仁不同饮片与其粉末色度值之间的相关性,建立薏苡仁不同饮片的数学判别模型和95%可信区间范围。结果:通过秩和检验与秩相关分析可知:L^(*)、a^(*)、E^(*)ab与样品之间存在高度相关性(P<0.05;|r|>0.8);通过Wilks′Lambda与Fisher判别分析,实现了薏苡仁不同饮片标准化判别,建立专属性线性判别函数:薏苡仁=447.378L^(*)+393.192a^(*)-289.087E^(*)ab-6664.567;法薏苡仁=268.996L^(*)+321.422a^(*)-116.086E^(*)ab-6352.510;麸炒薏苡仁=538.049L^(*)+470.526a^(*)-384.469E^(*)ab-6330.551,并通过交叉判别与L^(*)、a^(*)、E^(*)ab三维散点图得到验证。结论:本研究表明通过分光光度测色仪将薏苡仁不同饮片外观颜色数字化,结合统计学对其进行判别分析具有一定可行性,所建立的判别模型可为指导中药鉴别实践工作提供参考。

Objective:To establish an objective quantitative discrimination method for rapid differentiation of raw Semen Coicis,bran-fried Semen Coicis and Semen Coicis Preparatum,to provide scientific basis for process standardization and quality standard of different Semen Coicis decoction pieces,and to provide reference for the differentiation of other traditional Chinese medicine processed products.Methods:L^(*),a^(*)and b^(*)of raw Semen Coicis,bran-fried Semen Coicis and Semen Coicis Preparatum powder were determined by the spectrophotometer,and E^(*)ab was calculated.The correlation between different Semen Coicis decoction pieces and their L^(*),a^(*)and b^(*)was statistically analyzed.The discriminant mathematical model and 95%confidence intervals of different Semen Coicis decoction pieces were established.Results:The rank sum test and Spearman′s rank correlation showed that L^(*),a^(*)and E^(*)ab were highly correlated with the samples(P<0.05,|r|>0.8),and could be used as a criterion for determining the relationship between different Semen Coicis processed products and the three important parameters.By Wilks′Lambda and Fisher discriminant analysis,standardized discrimination of different Semen Coicis decoction pieces was realized,and specific linear discriminant functions were established:raw Semen Coicis=447.378L^(*)+393.192a^(*)-289.087E^(*)ab-6664.567;Semen Coicis Preparatum=268.996L^(*)+321.422a^(*)-116.086E^(*)ab-6352.510;bran-fried Semen Coicis=538.049L^(*)+470.526a^(*)-384.469E^(*)ab-6330.551,which were verified by cross discrimination and 3D scatter plot of L^(*),a^(*)and E^(*)ab.Conclusion:It was feasible to digitize the appearance and color of different Semen Coicis decoction pieces by spectrophotometer and carry out discriminant analysis on them in combination with statistics.The established discriminant model could provide reference for identifying traditional Chinese medicine.