Biological ingredient complement chemical ingredient in the assessment of the quality of TCM preparations

Traditional Chinese Medicine (TCM) preparations have been used in China for thousands of years. Quality evaluation for TCM preparations could be conducted based on chemical ingredients or biological ingredients. To date, the overwhelming majority of researches have focused on chemical ingredients while few studies were reported for biological ingredients. It is only recently that the assessments based on biological ingredients have drawn broader attentions. In this work, we have established a method for quality evaluation of TCM preparations by combination of chemical ingredients determined by HPLC fingerprint and biological ingredients obtained by high-throughput sequencing. This proof-of-concept method has been evaluated and compared with existing methods on Liuwei Dihuang Wan, a classical TCM preparation in China. By comparison of this method with those only based on chemical or biological ingredients, it is suggested that (1) Biological ingredient could complement chemical ingredient in separating TCM preparation from different manufacturers and batches with high accuracy; (2) classification of samples based on selected features would always out-perform those based on all features (either chemical or biological or both). By rationally selecting representative biological and chemical features, we have proven that these two types of features could complement each other for the assessment of ingredient consistencies and differences among various TCM samples, which is helpful to ensure the effectiveness, safety and legality of TCM preparations.