Anthelmintic activity of European fern extracts against Haemonchus contortus.

Most drugs used in the treatment of helminthiasis in humans and animals have lost their efficacy due to the development of drug-resistance in helminths. Moreover, since anthelmintics, like many pharmaceuticals, are now recognized as hazardous contaminants of the environment, returning to medicinal plants and their products represents an environmentally friendly way to treat helminthiasis. The goal of the present study was to test the anthelminthic activity of methanol extracts of eight selected European ferns from the genera Dryopteris, Athyrium and Blechnum against the nematode Haemonchus contortus, a widespread parasite of small ruminants. Eggs and adults of H. contortus drug-susceptible strain ISE and drug-resistant strain WR were isolated from experimentally infected sheep. The efficacy of fern extracts was assayed using egg hatch test and adults viability test based on ATP-level measurement. Among the ferns tested, only Dryopteris aemula extract (0.2 mg/mL) inhibited eggs hatching by 25% in comparison to control. Athyrium distentifolium, Dryopteris aemula and Dryopteris cambrensis were effective against H. contortus adults. In concentration 0.1 mg/mL, A. distentifolium, D. aemula, D. cambrensis significantly decreased the viability of females from ISE and WR strains to 36.2%, 51.9%, 32.9% and to 35.3%, 27.0%, 23.3%, respectively in comparison to untreated controls. None of the extracts exhibited toxicity in precise cut slices from ovine liver. Polyphenol's analysis identified quercetin, kaempferol, luteolin, 3-hydroxybenzoic acid, caffeic acid, coumaric acid and protocatechuic acid as the major components of these anthelmintically active ferns.

Antioxidant and Anti-Inflammatory Activity of Five Medicinal Mushrooms of the Genus Pleurotus.

Within the group of higher fungi, edible medicinal mushrooms have a long history of being used as food and in folk medicine. These species contain biologically active substances with many potential beneficial effects on human health. The Pleurotus genus is representative of medicinal mushrooms because Pleurotus ostreatus is one of the most commonly cultivated culinary mushrooms. In our study, we focused on lesser-known species in the genus Pleurotus and measured their antioxidant and anti-inflammatory activity. We prepared extracts of the mushrooms and analyzed them using HPLC-HRMS, GC-MS, and 1H-NMR. Significant differences in biological activities were found among the Pleurotus spp. extracts. A MeOH extract of P. flabellatus was the most active as a radical scavenger with the highest ORAC, while a chloroform extract had significant anti-inflammatory COX-2 activity. The 80% MeOH extract of P. flabellatus contained the highest amounts of ergosterol, ergothioneine, and mannitol. The 80% MeOH extract of P. ostreatus Florida was the most active in the NF-κB inhibition assay and had the highest content of ß-glucans (43.3% by dry weight). Given the antioxidant and anti-inflammatory properties of P. flabellatus, the potential therapeutic usefulness of this species is worth evaluating through in-depth investigations and confirmation by clinical trials.

C-geranylated flavonoids from Paulownia tomentosa Steud. fruit as potential anti-inflammatory agents.

ETHNOPHARMACOLOGICAL RELEVANCE: Paulownia tomentosa Steud., a traditional Chinese medicinal plant, was used for many centuries in Chinese herbal medicine as a component of remedies for many illnesses, including inflammatory diseases. It is a rich source of phenolic compounds, mainly geranylated flavonoids, which are currently studied for their promising biological activities. AIM OF THE STUDY: The study aimed to isolate minor geranylated flavanones and flavones from P. tomentosa fruit and evaluate their cytotoxicity and possible anti-inflammatory effects in a cell-based model of inflammation. MATERIALS AND METHODS: Chromatographic separation of chloroform portion of the ethanolic extract of P. tomentosa fruit led to the isolation of twenty-seven flavonoids (1-27), twenty-six of them geranylated with different modifications and one non-geranylated flavanone, and two phenolic compounds. Compounds were identified using UV, IR, HRMS, NMR, and CD spectroscopy. Ten of these compounds (7-10, 12, 21, 22, 24, 25, and 27) were determined to be new flavonoid derivatives obtained from a natural source for the first time. Selected compounds were analyzed for cytotoxicity and anti-inflammatory potential to affect the activation of nuclear factor κB/activator protein 1 (NF-κB/AP-1) after lipopolysaccharide (LPS) stimulation. RESULTS: All the test compounds (1-21 and 23-26) reduced the activation of NF-κB/AP-1 24 h after the addition of LPS. Eight compounds (5, 14-18, 21, and 26) were more active than prednisone, a widely used anti-inflammatory drug. However, this effect was not seen significantly on the level of TNF-α and IL-1ß, which can be explained by the plurality of possible outcomes of activation of the NF-κB pathway in cells. CONCLUSIONS: Results of the presented study confirmed that constituents from traditional Chinese medicinal plant P. tomentosa Steud. have promising anti-inflammatory activities and can serve as a potential source of inspiration for new anti-inflammatory medications.

Antiproliferative and cytotoxic activities of C-Geranylated flavonoids from Paulownia tomentosa Steud. Fruit.

Prenylated or geranylated flavonoids have been studied for their promising antiproliferative and cytotoxic activities. Twelve natural geranylated flavonoids (1-12) were isolated from the fruit of Paulownia tomentosa Steud. Their structures were elucidated using UV and IR spectroscopy, mass spectrometry, and 1D and 2D NMR spectroscopy. The absolute configurations were determined using NMR and circular dichroism. Seven of the compounds were characterized as new geranylated derivatives isolated from a natural source for the first time, namely 3'-O-methyl-5'-hydroxyisodiplacone (3), paulodiplacone A (5), tomentone II (6), tomentone B (7), tomentodiplacone P (8), paulodiplacone B (9), and tomentoflavone A (12). After 24 h of incubation at concentrations in the range 1-30 µM, the isolated compounds were tested for their antiproliferative and cytotoxic potentials against the human monocytic leukaemia cell line THP-1, using WST-1 and LDH assays, respectively. Almost all of the test compounds induced a concentration-dependent reduction in the metabolic activity of THP-1 cells and a concentration-dependent reduction in the cell viability. Diplacone (1) was the most potent antiproliferative and cytotoxic agent (IC50 9.31 ± 0.72 µM, LC50 18.01 ± 1.19 µM). 3'-O-Methyl-5'-hydroxydiplacone (2) showed relatively strong antiproliferative effect (IC50 12.61 ± 0.90 µM) and weaker cytotoxic activity (LC50 > 30 µM), indicating that it may serve as a potential lead compound for further testing. The structure-activity relationship for the 12 isolated compounds is discussed.

Screening of medicinal plants traditionally used in Peruvian Amazon for in vitro antioxidant and anticancer potential.

Plants mentioned in this study have numerous records in traditional Peruvian medicine being used in treatment of cancer and other diseases likely to be associated with oxidative stress. Amongst the eight plant species tested, only Dysphania ambrosioides exhibited combinatory antioxidant and anti-proliferative effect on a broad spectrum of cancer cells (DPPH and ORAC values = 80.6 and 687.3 µg TE/mg extract, respectively; IC50 against Caco-2, HT-29 and Hep-G2 = 129.2, 69.9 and 130.6, respectively). Alkaloids and phenolic compounds might significantly contribute to anticancer/antioxidant activity of this plant. The results justify the traditional medicinal use of this plant. Our findings further suggest that D. ambrosioides might serve as a prospective material for further development of novel plant-based antioxidant and/or anti-proliferative agents. Detailed analysis of chemical composition together with toxicology assessments and in vivo antioxidant/anti-proliferative activity of this plant should be carried out in order to verify its potential practical use.

Anti-Infectivity against Herpes Simplex Virus and Selected Microbes and Anti-Inflammatory Activities of Compounds Isolated from Eucalyptus globulus Labill.

Herpes simplex virus (HSV) causes numerous mild-to-serious human diseases, including mucocutaneous herpes infections and life-threatening herpes encephalitis. Moreover, herpes viral lesions can be complicated by inflammation and secondary bacterial infections. The development of resistance to antiviral drugs along with the undesirable side effects of these drugs are relevant argue for the development of new anti-HSV drugs with diverse mechanisms of action. Eucalyptus extracts have been used for decades to combat various infectious diseases. We isolated and studied 12 pure compounds and one mixture of two constitutional isomers from the leaves and twigs of E. globulus. The structures were identified by spectroscopic methods (NMR, HR-MS, IR) and all of them were tested for antiherpetic activity against the replication of antigen types HSV-1 and HSV-2. Tereticornate A (12) (IC50: 0.96 µg/mL; selectivity index CC50/IC50: 218.8) showed the strongest activity in the anti-HSV-1 assay, even greater than acyclovir (IC50: 1.92 µg/mL; selectivity index CC50/IC50: 109.4), a standard antiviral drug. Cypellocarpin C (5) (EC50: 0.73 µg/mL; selectivity index CC50/EC50: 287.7) showed the most potent anti-HSV-2 activity, also more intensive than acyclovir (EC50: 1.75 µg/mL; selectivity index CC50/EC50: 120.0). The antimicrobial activity of the isolated compounds was also evaluated against the bacteria Staphylococcus aureus, Bacillus cereus, Escherichia coli, and Pseudomonas aeruginosa and the yeast Candida albicans. The anti-inflammatory potential was examined using LPS-stimulated THP-1-XBlue™-MD2-CD14 and THP-1 macrophages and focusing on the influences of the NF-κB/AP-1 activity and the secretion of pro-inflammatory cytokines IL-1ß and TNF-α.

Phenolic composition, antioxidant and anti-proliferative activities of edible and medicinal plants from the Peruvian Amazon

ABSTRACT Among 23 extracts of medicinal and edible plants tested, Mauritia flexuosa L.f., Arecaceae, showed significant antioxidant ability (DPPH and ORAC = 1062.9 and 645.9 ± 51.4 µg TE/mg extract, respectively), while Annona montana Macfad., Annonaceae, demonstrated the most promising anti-proliferative effect (IC50 for Hep-G2 and HT-29 = 2.7 and 9.0 µg/ml, respectively). However, combinatory antioxidant/anti-proliferative effect was only detected in Oenocarpus bataua Mart., Arecaceae (DPPH = 903.8 and ORAC = 1024 µg TE/mg extract; IC50 for Hep-G2 and HT-29 at 102.6 and 38.8 µg/ml, respectively) and Inga edulis Mart., Fabaceae (DPPH = 337.0 and ORAC = 795.7 µg TE/mg extract; IC50 for Hep-G2 and HT-29 at 36.3 and 57.9 µg/ml, respectively). Phenolic content was positively correlated with antioxidant potential, however not with anti-proliferative effect. None of these extracts possessed toxicity towards normal foetal lung cells, suggesting their possible use in development of novel plant-based agents with preventive and/or therapeutic action against oxidative stress-related diseases.

Inhibition of in vitro leukotriene B4 biosynthesis in human neutrophil granulocytes and docking studies of natural quinones.

Quinones are compounds frequently contained in medicinal plants used for the treatment of inflammatory diseases. Therefore, the impact of plant-derived quinones on the arachidonic acid metabolic pathway is worthy of investigation. In this study, twenty-three quinone compounds of plant origin were tested in vitro for their potential to inhibit leukotriene B4 (LTB4) biosynthesis in activated human neutrophil granulocytes with 5-lipoxygenase (5-LOX) activity. The benzoquinones primin (3) and thymohydroquinone (4) (IC50 = 4.0 and 4.1 microM, respectively) showed activity comparable with the reference inhibitor zileuton (1C50 = 4.1 microM). Moderate activity was observed for the benzoquinone thymoquinone (2) (1C50 = 18.2 microM) and the naphthoquinone shikonin (1) (IC50 = 24.3 microM). The anthraquinone emodin and the naphthoquinone plumbagin (5) displayed only weak activities (IC50 > 50 microM). The binding modes of the active compounds were further evaluated in silico by molecular docking to the human 5-LOX crystal structure. This process supports the biological data and suggested that, although the redox potential is responsible for the quinone's activity on multiple targets, in the case of 5-LOX the molecular structure plays a vital role in the inhibition. The obtained results suggest primin as a promising compound for the development of dual COX-2/5-LOX inhibitors.

Redox and non-redox mechanism of in vitro cyclooxygenase inhibition by natural quinones.

In this study, ten anthra-, nine naphtho-, and five benzoquinone compounds of natural origin and five synthetic naphthoquinones were assessed, using an enzymatic in vitro assay, for their potential to inhibit cyclooxygenase-1 and -2 (COX-1 and COX-2), the key enzymes of the arachidonic acid cascade. IC50 values comparable with COX reference inhibitor indomethacin were recorded for several quinones (primin, alkannin, diospyrin, juglone, 7-methyljuglone, and shikonin). For some of the compounds, we suggest the redox potential of quinones as the mechanism responsible for in vitro COX inhibition because of the quantitative correlation with their pro-oxidant effect. Structure-relationship activity studies revealed that the substitutions at positions 2 and 5 play the key roles in the COX inhibitory and pro-oxidant actions of naphthoquinones. In contrast, the redox mechanism alone could not explain the activity of primin, embelin, alkannin, and diospyrin. For these four quinones, molecular modeling suggested similar binding modes as for conventional nonsteroidal anti-inflammatory drugs (NSAIDs).

Determination of oxygen radical absorbance capacity of black cumin (Nigella sativa) seed quinone compounds.

In this study, the antioxidant capacities of main quinone constituents of Nigella sativa seeds, namely dithymoquinone (1), thymohydroquinone (2) and thymoquinone (3), were compared using DPPH and ORAC methods. The best scavenging activity was produced by 2, which showed a remarkable activity of 2.60 Trolox equivalents (TE) in a concentration range between 1.6 and 6.4 microg/mL and IC50 value of 2.4 microg/mL in ORAC and DPPH assays, respectively. Contrastingly, 3 possessed only weak DPPH scavenging efficacy (IC50 = 170 microg/mL) but significant antioxidative action of 1.91 TE in ORAC assay. No effect has been observed for 1. Additionally, modified protocol for synthesis of 2 has been developed with aim to enhance its availability for further studies as well as for its future potential use. Based on the results of this study, we conclude that 2 could be considered as a compound with prospective antioxidative properties.

Evaluation of antimicrobial and anti-inflammatory activities of seed extracts from six Nigella species.

Seed extracts from six species of the genus Nigella (Family Ranunculaceae)-Nigella arvensis, Nigella damascena, Nigella hispanica, Nigella nigellastrum, Nigella orientalis, and Nigella sativa-obtained by successive extraction with n-hexane, chloroform, and methanol, were tested for their antimicrobial activity against 10 strains of pathogenic bacteria and yeast using the microdilution method as well as for anti-inflammatory properties by in vitro cyclooxygenase (COX)-1 and COX-2 assay. Chemical characterization of active extracts was carried out including free and fixed fatty acid analysis. Comparison of antimicrobial activity showed that N. arvensis chloroform extract was the most potent among all species tested, inhibiting Gram-positive bacterial and yeast strains with minimum inhibitory concentration (MIC) values ranging from 0.25 to 1 mg/mL. With the exception of selective inhibitory action of n-hexane extract of N. orientalis on growth of Bacteroides fragilis (MIC = 0.5 mg/mL), we observed no antimicrobial activity for other Nigella species. Anti-inflammatory screening revealed that N. sativa, N. orientalis, N. hispanica, N. arvensis n-hexane, and N. hispanica chloroform extracts had strong inhibitory activity (more than 80%) on COX-1 and N. orientalis, N. arvensis, and N. hispanica n-hexane extracts were most effective against COX-2, when the concentration of extracts was 100 microg/mL in both COX assays. In conclusion, N. arvensis, N. orientalis, and N. hispanica seeds, for the first time examined for antimicrobial and anti-inflammatory effects, revealed their significant activity in one or both assays.

In vitro inhibitory effects of thymol and quinones of Nigella sativa seeds on cyclooxygenase-1- and -2-catalyzed prostaglandin E2 biosyntheses.

Dithymoquinone, thymohydroquinone, thymol and thymoquinone, compounds derived from N. sativa seeds, were investigated for their in vitro anti-inflammatory activities using cyclooxygenase-1 (COX-1) and -2 (COX-2) assays. Our results show that all substances tested possess significant inhibitory activity against at least one COX form at concentrations comparable to the active one of indomethacin. Thymol was the most active against COX-1 with an IC (50) value of 0.2 microM while thymohydroquinone and thymoquinone exhibited the strongest inhibitory effect on COX-2 with IC (50) values of 0.1 and 0.3 microM, respectively. Moreover, dithymoquinone and thymoquinone showed a limited COX-2-specific inhibition. We conclude that dithymoquinone, thymohydroquinone, thymol and thymoquinone can participate in the general anti-inflammatory activity of N. sativa and suggest that these agents should be further studied for possible use as non-steroidal anti-inflammatory drugs.