3-4-di-o-caffeoylquinic-acid 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

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

The decoction of the whole plant of Elephantopus mollis Kunth. is traditionally consumed to treat various free radical-mediated diseases including cancer and diabetes.. This study was initiated to determine whether the most effective antioxidant compound isolated from the whole plant of Elephantopus mollis can also contribute to its claimed traditional values as anticancer and antidiabetes agents.. An active antiradical phenolic compound (3,4-di-O-caffeoyl quinic acid) was isolated from the methanol extract (with the highest in polyphenolic content) and their antioxidant activities were compared using four different assays, that are DPPH, FRAP, metal chelating, and β-carotene bleaching tests. The compound was also evaluated for its cytotoxic activity, apoptotic induction and anti-glucosidase efficacies using methylene blue, DeadEnd™ assay and α-glucosidase assays, respectively.. The compound acted as a greater primary antioxidant than its methanol extract, by having higher ferric reducing activity (EC(50) 2.18±0.05 μg/ml), β-carotene bleaching activity (EC(50) 23.85±0.65 μg/ml) and DPPH scavenging activity (EC(50) 68.91±5.44μg/ml), whereas the methanol extract exhibited higher secondary antioxidant activity as a metal chelator with lower EC(50) value (49.39±3.68 μg/ml) than the compound. Cytotoxicity screening of this compound exhibited a remarkable dose-dependent inhibitory effect on NCI-H23 (human lung adenocarcinoma) cell lines (EC(50) 3.26±0.35 μg/ml) and was found to be apoptotic in nature based on a clear indication of DNA fragmentation. This compound also displayed a concentration-dependent α-glucosidase inhibition with EC(50) 241.80±14.29 μg/ml.. The findings indicate the major role of 3,4-di-O-caffeoyl quinic acid to antioxidant capacities of Elephantopus mollis extracts. The compound also exerted apoptosis-mediated cytotoxicity and α-glucosidase inhibitory effects and is thus a promising non toxic agent in treating cancer and type 2 diabetes mellitus.

Topics: Adenocarcinoma; Antineoplastic Agents, Phytogenic; Antioxidants; Apoptosis; Asteraceae; beta Carotene; Biphenyl Compounds; Cell Line, Tumor; Chelating Agents; Chlorogenic Acid; DNA Fragmentation; Dose-Response Relationship, Drug; Enzyme Inhibitors; Ferric Compounds; Glycoside Hydrolase Inhibitors; Humans; Lung Neoplasms; Picrates; Plant Extracts; Polyphenols

The methanol extract from Dipsacus asper Wall (Dipsacaceae) was found to show antioxidant activity against free radical and Cu(2+)-mediated LDL oxidation. In further study, to identify active constituents from the plant, six caffeoyl quinic acid derivatives: 3,4-di-O-caffeoylquinic acid (1), methyl 3,4-di-O-caffeoyl quinate (2), 3,5-di-O-caffeoylquinic acid (3), methyl 3,5-di-O-caffeoyl quinate (4), 4,5-di-O-caffeoylquinic acid (5) and methyl 4,5-di-O-caffeoyl quinate (6) were isolated. Their structures were identified by spectroscopic methods including 2D-NMR. The isolated compounds, 1-6, were found to be potent scavengers of the free radical 1,1-diphenyl-2-picrylhydrazyl (DPPH), and are more potent than butylated hydroxyl toluene (BHT) used as a positive control. The compounds 1-6 also inhibited Cu(2+)-mediated low-density lipoprotein (LDL) oxidation. They increased the lag time of conjugated dienes formation and inhibited the generation of thiobarbituric acid reactive substances (TBARS) in a dose-dependent manner. These results suggested that Dipsacus asper due to its antioxidant constituents, 1-6, may have a role to play in preventing the development and progression of atherosclerotic disease.

Topics: alpha-Tocopherol; Antioxidants; Biphenyl Compounds; Butylated Hydroxytoluene; Caffeic Acids; Chlorogenic Acid; Copper; Dipsacaceae; Dose-Response Relationship, Drug; Free Radical Scavengers; Gallic Acid; Humans; Hydrazines; Lipid Peroxidation; Lipoproteins, LDL; Malondialdehyde; Methanol; Molecular Structure; Monosaccharides; Picrates; Plant Extracts; Plant Roots; Plants, Medicinal; Quinic Acid; Thiobarbituric Acid Reactive Substances