For the determination of seven caffeoylquinic acids [neochlorogenic acid (NcA), cryptochlorogenic acid (CcA), chlorogenic acid (CA), caffeic acid (CfA), isochlorogenic acid A (Ic A), isochlorogenic acid B (Ic B), isochlorogenic acid C (Ic C)] and two flavonoids [luteolin 7-O-glucoside (LtG) and luteolin (Lt)], a three-channel liquid chromatography with electrochemical detection (LC-3ECD) method was established. Chromatographic peak heights were proportional to each concentration, ranging from 2.5 to 100 ng/mL for NcA, CA, CcA, and CfA, and ranging from 2.5 to 250 ng/mL for LtG, Ic B, Ic A, Ic C, and Lt, respectively. The present LC-3ECD method was applied to the quantitative analysis of caffeoylquinic acids and flavonoids in four cultivars of Chrysanthemum morifolium flowers and their sulfur-fumigated products. It was found that 60% of LtG and more than 47% of caffeoylquinic acids were lost during the sulfur fumigation processing. Sulfur fumigation showed a destructive effect on the C. morifolium flowers. In addition, principle component analyses (PCA) were performed using the results of the quantitative analysis of caffeoylquinic acids and flavonoids to compare the "sameness" and "differences" of these analytes in C. morifolium flowers and the sulfur-fumigated products. PCA score plots showed that the four cultivars of C. morifolium flowers were clearly classified into four groups, and that significant differences were also found between the non-fumigated C. morifolium flowers and the sulfur-fumigated products. Therefore, it was demonstrated that the present LC-3ECD method coupled with PCA is applicable to the variation analysis of different C. morifolium flower samples.
Key wordsChrysanthemum morifolium flower; caffeoylquinic acid; flavonoid; sulfur-fumigation; electrochemical detectionThe dried capitulum of Chrysanthemum morifolium RAMAT. (Compositae), Flos Chrysanthemi called 'Ju Hua' in China, is a well-known herbal medicine, tea material, and food resource in many Asian countries such as China, Japan, South Korea, and Thailand. 1) In China, there are many cultivars of C. morifolium flowers available. Among these cultivars, four major varieties of C. morifolium cv. 'Hangju' (HJ), 'Boju' (BJ), 'Chuju' (CJ), and 'Gongju' (GJ) have been recorded in the Chinese Pharmacopeia as standard varieties of C. morifolium flowers for their therapeutic effects of scattering cold, cleaning heat and toxin properties, and brightening eyes.2) C. morifolium flower was abundant in caffeoylquinic acids and flavonoids, which were considered to be the main bioactive components. Modern pharmacological studies revealed that these components from C. morifolium flowers possess extensive biological activities, such as anti-oxidation, 3,4) anti-mutagenesis,
5)cardiovascular protection, 6,7) anti-cancer,
8)anti-human immune deficiency viruses, 9) etc. Therefore, it is significant to evaluate the quality of the C. morifolium flower by quantitatively analyzing these bioactive components.Most medicinal herbs need to undergo a post-harvestin...