RESUMO
There are more and more literature reports about the application of Chinese medicine quality constant in the grading evaluation of Chinese medicine decoction pieces. Chinese medicine quality constant has particularly prominent advantages in comprehensive quantification,so it has become a new method and mode for grading Chinese medicine decoction pieces,highly recognized by the academic circle. In order to determine the effect of Chinese medicine quality constant,a method of grades evaluation for Moutan cortex was established in this paper. 15 batches of samples were collected from Chinese herbal slices enterprises to determine the external morphological indexes and inner quality indexes,calculate the Chinese medicine quality constant of Moutan cortex,and divide them into different grades. The results revealed that the range of the relative quality constant of these samples was from 0. 016 to 0. 060,with percentage quality constant from 27. 4 to 100. 0. If these samples were divided into three grades: the quality constant of the first grade should be ≥0. 048 or the percentage quality constant ≥80. 0; the quality constant of the second grade should be <0. 048 but ≥0. 030 or percentage quality constant <80. 0 and ≥50. 0; the quality constant of the third grade should be <0. 030 or the percentage quality constant <50. 0. This research indicated that Chinese quality constant can objectively divide grades of Moutan cortex decoction pieces,providing reference for formulating grades standards. It was also verified from the results that traditional quality evaluation of Moutan cortex was consistent with quality constant,and the connotation of percentage quality constant was elaborated as well. At the same time,it is suggested to establish a third-party Chinese medicine slices rating agency as soon as possible,which is to unify the terminology and provide rating services for the market.