Quality evaluation based on color grading - relationship between chemical susbtances and commercial grades by machine version in Corni fructus

Purpose: To evaluate the correlation between the commercial grade of Corni fructus determined by machine vision technology, and its chemical composition. Methods: Loganin, morroniside, ursolic acid, water-soluble extractives, alcohol-soluble extractives, polysaccharides and total organic acids were quantitated in four Corni fructus grades classified by machine vision technology. The content of each component was determined and analyzed bymathematical statistics. Results: Compared with low-grade samples, higher-grade counterparts contained elevated concentrations of alcohol-soluble extractives, water-soluble extractives, loganin and morroniside. In addition, principal component analysis revealed a correlation coefficient of -0.723 between Corni fructus grade and Holistic Scoring based on chemical composition, indicating a significant correlation (p < 0.01). Conclusion: These findings indicated the rationality of the classification method based on machine vision, and further confirmed the notion of  "quality evaluation based on color" of traditional Chinese medicine. Keywords: Corni fructus, Commercial grade, Machine vision technology, Chemical substance