[Discrimination of Coptidis Rhizoma and its processed products by odor objectify]

Different processed products of Coptidis Rhizoma have its unique odor, which is an important assessment index for pro- cessed products identification of Coptidis Rhizoma. Objectify odor as an entry point in this study, an electronic nose technology was used, and a suitable method for Coptidis Rhizoma measurement was built firstly. Then different processed products of Coptidis Rhizoma were detected by the method built. Finally, different processed products were identified by combining with chemometrics based on the objective odor information obtained. Electronic nose detection indicated that a significant difference in odor between different processed products was performed. Coptidis Rhizoma processed or not can be distinguished based on statistical quality control (SQC) and soft independent modeling of class analogy (SIMCA). Principle component analysis (PCA) model showed that Coptidis Rhizoma and its various processed products discriminated obviously. In addition, in order to identify the processed products of Coptidis Rhizoma, a correct recognition rate of 100% was acquired by discriminant factor analysis (DFA) , and the initial identification rate and cross-validation recognition rate of linear discriminant analysis (LDA) is 100%, 94.4% respectively. In conclusion, differentiationin odor of different processed Coptidis Rhizoma was performed by the electronic nose technology used, and different products Coptidis Rhizoma were dis- criminated by combining with chemometrics. This research can be a reference for objective identification in odor of traditional Chinese medicine, and is good for the inheritance and development of traditional experience in odor identification.