[Three-dimensional multi-component quality evaluation of Chinese medicine based on proportion consistency of active components: a study of Salvia miltiorrhiza].

To reveal the law of the proportion consistency of the active components in Chinese medicine and explore a new way to evaluate the quality of Chinese medicine, the present study investigated the content of tanshinone Ⅱ_A, cryptotanshinone, tanshinone Ⅰ, salvianolic acid B, rosmarinic acid, caffeic acid, and lithospermic acid in 895 samples of Salvia miltiorrhiza from 87 literature articles. The samples with salvianolic acid B and tanshinones(total content of tanshinone Ⅱ_A, tanshinone Ⅰ, and cryptotanshinone) meeting the requirements of Chinese Pharmacopoeia were analyzed for proportion consistency of components, and the proportion distribution of components was compared. The results showed that the proportions in and between tanshinones and salvianolic acids were stable. The content ratios of cryptotanshinone to tanshinone Ⅱ_A, rosmarinic acid to salvianolic acid B, and salvianolic acid B to tanshinone Ⅱ_A fluctuated from 0.1 to 1.7, from 0.02 to 0.14, and from 10 to 60, respectively. It indicated that the content proportions of different components were not fixed, but fluctuated in a certain range. The fluctuation range of components in the same group was small, but that in different groups was large. The content proportions of active components were stable for Chinese medicinal materials with fixed varieties or origins. The samples whose content proportions were out of the fluctuation ranges were generally unqualified medicinal materials. We proposed a "three-dimensional multi-component" quality evaluation model of Chinese medicine based on the above findings. Specifically, "three-dimensional" means to accurately evaluate the quality of Chinese medicine from varieties, proportions, and content of active components, and "multi-component" means to highlight the information of multiple components in Chinese medicine, especially the quality markers and equivalent component groups. The proportion of components in Chinese medicine can be used as an important index for the quality evaluation of Chinese medicine. The proportions of active components are stable in Chinese medicinal materials with fixed varieties or places of origin.