indigo-carmine and 1-1-diphenyl-2-picrylhydrazyl

To investigate the bioactive constituents of the inflorescences of Scabiosa comosa and S. tschilliensis, which are used traditionally for liver diseases, we tested the antioxidant activity using 2,2'-diphenyl-1-picrylhydrazyl (DPPH), 2,2'-azinobis-(3-ethylbenzthiazoline-6-sulphonic acid) (ABTS), ferric reducing antioxidant potential (FRAP), and DPPH-ultra high performance liquid chromatography-mass spectrometer (UPLC-MS) assay. In addition, cell-based anti-HCV activity of the major compounds were evaluated. The plant extracts showed strong antioxidant activity. For the first time, 3,4-dicaffeoylquinic acid (DCQA), 3,5-DCQA and 4,5-DCQA were identified from genus Scabiosa. A UPLC-MS method in multiple reaction monitoring (MRM) mode was established to quantify 18 constituents in the inflorescences of Scabiosa. The 3,5-DCQA, chlorogenic acid and some glycosides of luteolin or apigenin were found to be the most abundant constituents. Chlorogenic acid and 3,5-DCQA showed excellent radical scavenging activity and demonstrated anti-HCV activity. These findings provided scientific evidences for the clinic use of this herbal medicine for liver diseases.

Topics: Antioxidants; Antiviral Agents; Biphenyl Compounds; Chlorogenic Acid; Dipsacaceae; Free Radical Scavengers; Hepacivirus; Humans; Luteolin; Picrates; Plant Extracts; Quinic Acid; Spectrometry, Fluorescence

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

From an extract of the aerial parts of Dracocephalum ruyschiana, five new flavone tetraglycosides, five new benzyl alcohol glycosides, and 19 known compounds were isolated. The tetraglycosides contain a 7-O-β-d-glucopyranosyl-(1→2)-β-d-glucopyranosyl-(1→2)-[α-l-rhamnopyranosyl-(1→6)]-β-d-glucopyranosyl moiety. The benzyl alcohol glycosides had acyl groups on their glycosyl or aglycone moieties. The compounds were tested for antioxidant activity using DPPH. Although the new compounds were not active, phenylpropanoylquinic acid derivatives were revealed as radical scavengers in D. ruyschiana.

Topics: Antioxidants; Benzyl Alcohol; Biphenyl Compounds; Flavones; Free Radical Scavengers; Glycosides; Lamiaceae; Molecular Structure; Mongolia; Picrates; Plants, Medicinal

Although Artemisia gmelinii Webb. ex Stechm. has long been used in south and south-east Asia to treat many kinds of inflammatory diseases, up until now its bioactivity-coupled phytochemical characterization has not been reported. We identified one fraction of the methanolic extract of A. gmelinii as a hit in our antioxidant screening (DPPH) campaign. In order to identify the active radical scavenger components of the extract, a DPPH-HPLC spiking assay was carried out. Out of six detected known compounds caffeic acid and scopoletin had already been identified in the plant, but four of them, namely chlorogenic acid, 4-O-caffeoylquinic acid, luteolin-7-O-glucoside, and apigenin-7-O-glucoside are first described here. Moreover, the two most active compounds of the mixture, 3,5-O-dicaffeoylquinic acid (7) and its ethyl ester derivative (8) were isolated with preparative HPLC. The spectroscopic identification of 7 and 8 presented a surprising challenge due to literature ambiguities. These questions are discussed in detail.

Topics: Artemisia; Biphenyl Compounds; Chlorogenic Acid; Chromatography, High Pressure Liquid; Free Radical Scavengers; Free Radicals; Magnetic Resonance Spectroscopy; Models, Molecular; Picrates; Plant Components, Aerial; Plant Extracts; Spectrometry, Mass, Electrospray Ionization; Structure-Activity Relationship