benzofurans and diffractaic-acid

Topics: Animals; Anisoles; Benzofurans; Chromatography, High Pressure Liquid; Female; Hydroxybenzoates; Linear Models; Male; Mass Spectrometry; Phthalic Acids; Rats; Reproducibility of Results; Sensitivity and Specificity

The major bioactive constituents of Usnea longissima Ach. are organic acids. However, few recent literatures involve the preparative separation of these organic acids. In the present study, pH zone-refining counter-current chromatography is used to separate organic acids from crude sample of U. longissima Ach. The crude extract was separated with the two-phase solvent system Pet-EtAc-MeOH-H2O (5:5:3:7, v/v) with 10mM TFA in organic stationary phase and different concentration of the eluter in aqueous mobile phase for the screening of the most suitable separation conditions. From the crude extract (1.2g), 74.0mg of orsellinic acid at 92.7% purity, 55.5mg of 4-O-methylorsellinic acid at 97.7% purity, 353.5mg of evernic acid at 93.8% purity, 102.0mg of barbatic acid at 94.8% purity, 19.4 mg of diffractaic acid at 92.2% purity, and 44.9 mg of usnic acid at 95.7% purity were obtained using the selected conditions in which the concentration of TFA in stationary phase was 10mM and the concentration of NaOH in mobile phase was 10-20mM. The purities of the separated organic acids were measured by HPLC. And the data of electrospray ionization-liquid chromatography/mass spectrometry (ESI-LC/MS), (1)H NMR, and (13)C NMR were used for confirming chemical structures.

Topics: Anisoles; Benzofurans; Chromatography, High Pressure Liquid; Countercurrent Distribution; Hydrogen-Ion Concentration; Hydroxybenzoates; Phthalic Acids; Resorcinols; Spectrometry, Mass, Electrospray Ionization; Usnea

The purpose of this study was to investigate the effects of six lichen metabolites (diffractaic acid, lobaric acid, usnic acid, vicanicin, variolaric acid, protolichesterinic acid) on proliferation, viability and reactive oxygen species (ROS) level towards three human cancer cell lines, MCF-7 (breast adenocarcinoma), HeLa (cervix adenocarcinoma) and HCT-116 (colon carcinoma). Cells were treated with different concentrations (2.5-100 μM) of these compounds for 48 h. In this comparative study, our lichen metabolites showed various cytotoxic effects in a concentration-dependent manner, and usnic acid was the most potent cytotoxic agent, while variolaric acid did not inhibit the proliferation of any of the three cell lines used. All tested lichen compounds did not exhibit free radical scavenging activity using the 1,1-diphenyl-2-picrylhydrazyl (DPPH) assay. The lichen metabolites did not significantly increase the intracellular ROS level and did not prevent oxidative injury induced by t-butylhydroperoxide in HeLa cells. To better clarify the mechanism(s) of cytotoxic effect induced by protolichesterinic acid in HeLa cells, we investigated apoptotic markers such as condensation and fragmentation of nuclear chromatin and activation of caspase-3, 8 and 9. Our results revealed that the antiproliferative activity of 40 μM protolichesterinic acid in HeLa cells is related to its ability to induce programmed cell death involving caspase-3, 8 and 9 activation.

Topics: 4-Butyrolactone; Anisoles; Antioxidants; Apoptosis; Benzofurans; Caspases; Cell Line, Tumor; Cell Proliferation; Cell Survival; Depsides; Free Radical Scavengers; Humans; Hydroxybenzoates; Lactones; Lichens; Oxidative Stress; Reactive Oxygen Species; Salicylates

Based on results of a former study in 2005, this investigation aimed at quantifying UV- and cold temperature stress-induced changes within the secondary metabolite production of the cultured mycobiont of the lichen Heterodea muelleri (Hampe) Nyl. The chemical profiles of the mycobiont cultures and the lichen thallus were determined by high-performance liquid chromatography (HPLC) and thin layer chromatography (TLC) analyses. The voucher specimen of H. muelleri produced diffractaic acid as a major polyketide and barbatic acid as a satellite compound, whereas the untreated mycobiont did not contain any detectable secondary metabolites. While UV-C stress caused a general increase in substance formation, cold temperature stress resulted in a strong activation of barbatic acid biosynthesis. A further series of experiments focused on the effect of diffractaic and barbatic acids on the growth of the symbiotic photobiont Trebouxia jamesii; usnic acid was similarly tested. Pure substances were obtained from mycobiont cultures by performing preparative TLC. A determined quantity of algae was incubated on BBM plates that contained three different concentrations of the pure lichen metabolites. The growth of the photobionts was monitored over a period of 1 mo to evaluate the impact of each substance on the cultured algae. While diffractaic and usnic acid had no noticeable effect, barbatic acid strongly inhibited algal growth and resulted in cell death.

Topics: Anisoles; Ascomycota; Benzofurans; Chlorophyta; Hydroxybenzoates; Lichens; Phthalic Acids

The sensitivity of the human keratinocyte cell line HaCaT to several lichen metabolites isolated from Parmelia nepalensis and Parmelia tinctorum was evaluated. The tridepside gyrophoric acid (6), the dibenzofuran derivative (+)-usnic acid (1), and the didepside diffractaic acid (5) were potent antiproliferative agents and inhibited cell growth, with IC50 values of 1.7, 2.1, and 2.6 microM, respectively. Methyl beta-orcinolcarboxylate (2), ethyl hematommate (3), the didepside atranorin (4), and (+)-protolichesterinic acid (7) did not influence keratinocyte growth at concentrations of 5 microM. Keratinocytes were further tested for their susceptibility to the action of the potent antiproliferative agents on plasma membrane integrity. The release of lactate dehydrogenase activity into the culture medium was unchanged as compared to controls, documenting that the activity of gyrophoric acid (6), (+)-usnic acid (1), and diffractaic acid (5) was due to cytostatic rather than cytotoxic effects.

Topics: Anisoles; Antineoplastic Agents; Arachidonic Acid; Benzoates; Benzofurans; Cell Division; Humans; Hydroxybenzoates; Keratinocytes; L-Lactate Dehydrogenase; Lichens; Lipoxygenase; Tumor Cells, Cultured

Diffractaic acid and usnic acid were identified as the analgesic and antipyretic components of a lichen, Usnea diffracta. Both compounds showed an analgesic effect by the acetic acid-induced writhing and tail-pressure methods in mice. Regarding the effect on normal body temperature and LPS-induced hyperthermia in mice, diffractaic acid showed a significant effect only on the former and usnic acid only on the latter.

Topics: Analgesics; Analgesics, Non-Narcotic; Anisoles; Benzofurans; Chromatography, Thin Layer; Hydroxybenzoates; Magnetic Resonance Spectroscopy; Plants, Medicinal; Spectrophotometry, Infrared