Abstract

Zhishi is one of the most commonly used traditional Chinese medicinal plants. Many species ofCitrus plants, such as Citrus aurantium L. and its cultivars, Citrus sinensis Osbeck and its cultivars, and Citrus junos Sieb. ex Tanaka, can be used as Zhishi. However, Zhishi from different species exhibited differences in their therapeutic effects. In addition, it was very difficult to distinguish the species due to their similar morphologies. Flavanone compounds are the main bioactive constituents of Zhishi; in this study, flavanones were used as chemotaxonomic markers to distinguish among different Citrus samples. The contents of four flavanones (narirutin, naringin, hesperidin and neohesperidin) of 77 Zhishi samples from threeCitrus species were determined using rapid resolution liquid chromatography-diode array detection/UV (RRLC-DAD/UV) and multivariate statistical analysis. Principal component analysis (PCA) of the quantitative data showed a clear separation of compositions among the three species of Zhishi samples. Furthermore, the established differential mode was subsequently applied to identify the origin of unknown commercial samples.

Key words: Zhishi, Citrus species, flavanone, rapid resolution liquid chromatography (RRLC), multivariate statistical analysis.