The taste sensory evaluation of medicinal plants and Chinese medicines

The purpose of this study was to investigate the use of the artificial taste sensor in the evaluation of I I medicinal plants and 10 Chinese medicines with bitter and/or astringent tastes, and to assess the possible application of the sensor in the evaluation of taste and quality control of medicinal products. Aqueous extracts of the six bitter medicinal plants could be classified into three types, and those of the five astringent medicinal plants into two types, on the basis of sensor output pattern profiles. These differences seem to derive from the different structures of the main components. In the principal component analysis of the taste sensor output of 10 Chinese medicines, a new measure developed, the 'Euclidean distance', defined as the distance between a control and the targeted substance on the principal component map. This measure offers a possibility for indicating the different tastes of Chinese medicines. Lastly, we confirmed that berberine adsorption on the surface of the artificial membrane of the taste sensor was of the Langmuir type. The berberine content in extracts of medicinal plants could be evaluated by the taste sensor, and it was shown to be possible to use the taste sensor for the quality control of medicinal plants. (C) 2007 Elsevier B.V. All rights reserved.