[Quality evaluation of Cnidii Fructus in commodity grade based on theory of "quality evaluation through morphological identification"].

From the perspective of market classification of Cnidii Fructus, this paper revealed the scientific connotation of evaluating the quality grade of Cnidii Fructus by its appearance traits. Thirty batches of Cnidii Fructus in different grades were selected as the research objects. The canonical correlation analysis and principal component analysis(PCA) were used to explore the measurement values of 15 appearance traits and intrinsic content indexes. The results of correlation analysis showed that except the aspect ratio, the 5 appearance trait indexes(length, width, 1 000-grain weight, broken grain weight proportion, and chroma) and 9 internal content indexes(the content of moisture, total ash, acid insoluble ash, osthole, imperatorin, 5-methoxy psoralen, isopimpinellin, xanthotoxin, and xanthotol) showed significant correlation to varying degrees. In addition, there was a significant positive correlation between the first typical variable U_1 composed of appearance traits and the first typical variable V_1 composed of internal content indexes(CR_1=0.963, P<0.01). The results of PCA showed that the classification results of appearance traits for 30 batches of Cnidii Fructus were consistent with the actual information of the samples. Under the same analysis conditions, 30 batches of Cnidii Fructus were reclassified by 9 groups of internal content indexes, and the analysis results were consistent. From the classification standard of the appearance traits of the system study, the statistical results of 6 appearance traits of Cnidii Fructus showed a correlation with grades. There was a good correlation between the appearance and the internal content of Cnidii Fructus, and the appearance quality effectively predicted the level of the internal content. There is a certain scientific basis for the quality classification of Cnidii Fructus by main appearance traits. Appearance classification can replace quality grading to realize the "quality evaluation through morphological identification" of Cnidii Fructus.