marein and okanin

In this study, phenolic profiles of chrysanthemums derived from five main species were determined for characterization of rationality of their application in tea, beverages and functional foods. A total of 41 phenolics including 3 phenolic acids, 17 flavones, 9 flavanones, 1 dihydroflavonol, 4 flavonols, 4 chalcones and 3 aurones were identified. The contents of 22 characteristic phenolics were simultaneously determined. Chrysanthemum morifolium cv. 'Qiju' (with abundant phenolics) and Coreopsis tinctoria Nutt. (with unique and abundant flavonoid aglycones and glycosides), exhibited excellent cellular antioxidant activities and strong market potentials. Chlorogenic acid, 3,5-dicaffeoylquinic acid and luteolin-7-O-glucoside largely contributing to cellular antioxidant activity of 'Qiju' by forming protective membrane around erythrocyte should be markers for quality control of 'Qiju'. Okanin, the gut microbial-produced metabolite of marein, possessed strong protective effect on oxidatively damaged erythrocyte via incorporating in membrane and entering cytoplasm. Okanin and marein should be markers for quality control of C. tinctoria.

Topics: Animals; Antioxidants; Chalcones; Chlorogenic Acid; Chrysanthemum; Coreopsis; Erythrocytes; Flavanones; Flavones; Flavonoids; Hemolysis; Hydroxybenzoates; Male; Malondialdehyde; Oxidative Stress; Phenols; Plant Extracts; Quinic Acid; Rats; Rats, Sprague-Dawley; Reactive Oxygen Species; Tandem Mass Spectrometry

A simple and efficient method based on high-performance thin-layer chromatography coupled with 2,2-diphenyl-1-picrylhydrazyl (DPPH) bioautography (HPTLC-DPPH) was established for the screening and comparison of antioxidants in different parts of Coreopsis tinctoria herbal tea from different origins and other related herbal tea materials, which used Chrysanthemum morifolium cv. "Gongju" and "Hangju" in this study. Scanning densitometry after DPPH derivatization was applied for the determination of antioxidant capacities of isolated compounds in each sample. It is considered that ethanol extracts of C. tinctoria had stronger antioxidant activity and more characteristic bands than those of 2 compared samples, C. morifolium cv. "Gongju" and "Hangju." Chemometric analysis results showed that the combination of hierarchical clustering analysis and principal component analysis based on determined antioxidant capacities could be used for the discrimination of different parts of C. tinctoria and C. morifolium. Results showed that 7 compounds made up the major contributions of antioxidant activity in C. tinctoria, including okanin, isookanin, marein, flavanomarein, 5,7,3',5'-tetrahydroxyflavanone-7-O-glucoside, 3,5-dicaffeoylquinic acid, and chlorogenic acid. Therefore, 7 compounds were identified as major antioxidant biomarkers for quality control of C. tinctoria. Results demonstrated that the established method could be applied for the identification of C. tinctoria, and were beneficial for the bioactivity-based quality control of C. tinctoria.

Topics: Antioxidants; Biphenyl Compounds; Chalcones; Chlorogenic Acid; Chromatography, Thin Layer; Chrysanthemum; Coreopsis; Densitometry; Flavanones; Picrates; Plant Extracts; Quality Control; Quinic Acid; Teas, Herbal

Infusions of Coreopsis tinctoria flowering tops have traditionally been used in Portugal to control hyperglycaemia but no pharmacological or toxicological studies have been reported until now. The chalcones marein and okanin were isolated from the aqueous extract, together with the 2S-3',4',7,8-tetrahydroxyflavanone. The content of marein in extracts was determined by HPLC-UV and the radical scavenging capacity evaluated by the DPPH method (EC(50) = 21 microg/mL). Glucose intolerance was induced by a single intraperitoneal injection of streptozotocin in saline (40 mg/Kg). After three weeks of oral treatment with C. tinctoria extract (500 mg/Kg/day) the animals were no longer glucose-intolerant (p > 0.05). Additionally, this oral treatment caused no hepatotoxicity in the rats, as determined by blood alanine and aspartate transaminases. A single administration of extract had no effect on oral glucose tolerance in normal Wistar rats. The extract also had no effect on insulin secretion by MIN6 cells. In conclusion, C. tinctoria infusion is able to abolish the streptozotocin-induced glucose-intolerance in rats after three weeks of oral treatment by a mechanism other than induction of insulin secretion. The recovery of beta-pancreatic function mediated by an antioxidant mechanism is a possibility that deserves further investigation.

Topics: Administration, Oral; Animals; Cell Line; Chalcones; Coreopsis; Drug Evaluation, Preclinical; Flavanones; Glucose Intolerance; Glucose Tolerance Test; Hypoglycemic Agents; Male; Mice; Phytotherapy; Plant Extracts; Rats; Rats, Wistar