Development of dandelion (Taraxacum spp.) quality evaluation technology based on phenolic acids

Abstract One of the main purposes for which dandelions are cultivated is to derive phenolic acids from their processing. Phenolic acids, which are one of the main useful compounds in dandelion, constitute one of the important groups of therapeutically significant bioactive compounds in traditional Chinese medicine. To carry out a relatively full evaluation of dandelion quality, it was found advisable to use multiple indices to avoid conflict with the single evaluation index stipulated by China Pharmacopoeia. Thus, a quality evaluation method was created based on traditional Chinese medicinal theory and relevant statistics on phenolic acids. Firstly, four main kinds of phenolic acids – caftaric acid, chlorogenic acid, caffeic acid and cichoric acid – were chosen as the main indices for quality evaluation through the optimisation of high performance liquid chromatography detection conditions and fingerprint comparison analysis; then, the content of each component was divided into five levels based on the descriptive statistics of 578 dandelion samples and references; finally, the equal weight average method was used to convert content levels of the four components into a comprehensive quality index, which served as the means for dandelion quality to be identified and segregated into grades, as follows: Grade 1 (super high, probability of 0.8%), Grade 2 (high, 18.72%), Grade 3 (medium, 37.28%), Grade 4 (qualified, 32%) and Grade 5 (low, 11.2%). This method is the first to comprehensively evaluate dandelion quality for setting an industry standard in China, and has practical and scientific characteristics.