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Background/Objectives: Hibiscus sabdariffa L. (H. sabdariffa (HS)) extract has a vascular relaxant effect on isolated rat thoracic aorta, but data on small resistance arteries, which play an important role on the development of hypertension, are still missing. The purposes of this study were (1) to assess the effect on isolated mesenteric arteries (MA) from normotensive (Wistar and Wistar-Kyoto (WKY)) and spontaneous hypertensive rats (SHR), (2) to elucidate the mechanism(s) of action underling the relaxant effect in light of bioactive components. Methods: Vascular effects of HS aqueous fraction (AF) on isolated MA rings, as well as its mechanisms of action, were assessed using the contractility and intracellular microelectrode technique. The patch clamp technique was used to evaluate the effect of HS AF on the L-type calcium current. Extraction and enrichment of AF were carried out using liquid&ndash, liquid extraction, and the yield was analyzed using HPLC. Results: The HS AF induced a concentration-dependent relaxant effect on MA rings of SHR (EC50 = 0.83 &plusmn, 0.08 mg/mL), WKY (EC50 = 0.46 &plusmn, 0.04 mg/mL), and Wistar rats (EC50 = 0.44 &plusmn, 0.08 mg/mL) pre-contracted with phenylephrine (10 &micro, M). In Wistar rats, the HS AF maximum relaxant effect was not modified after endothelium removal or when a guanylate cyclase inhibitor (ODQ, 10 &micro, M) and a selective &beta, 2-adrenergic receptor antagonist (ICI-118551, 1 &micro, M) were incubated with the preparation. Otherwise, it was reduced by 34.57 &plusmn, 10.66% when vascular rings were pre-contracted with an 80 mM [K+] solution (p &lt, 0.001), which suggests an effect on ionic channels. HS AF 2 mg/mL significantly decreased the peak of the L-type calcium current observed in cardiac myocytes by 24.4%. Moreover, though the vasorelaxant effect of HS, AF was reduced by 27% when the nonselective potassium channels blocker (tetraethylammonium (TEA) 20 mM) was added to the bath (p &lt, 0.01). The extract did not induce a membrane hyperpolarization of smooth muscle cells, which might suggest an absence of a direct effect on background potassium current. Conclusion: These results highlight that the antihypertensive effect of HS probably involves a vasorelaxant effect on small resistance arteries, which is endothelium independent. L-type calcium current reduction contributes to this effect. The results could also provide a link between the vasorelaxant effect and the bioactive compounds, especially anthocyanins.

International audience; Aristolochic acids are biologically active and highly toxic secondary metabolites that recently became an important pharmacological tool for in vivo models of acute kidney disorders. Only aristolochic acid I and a mixture of aristolochic acids I and II are currently commercially available. A method based on the strong-ion exchange displacement mode in centrifugal partition chromatography was developed to extract and purify arictolochic acids, naturally present in Aristolochia bracteolata Lam. (Aristolochiaceae). The extraction and purification of aristolochic acids were performed at a flow rate of 2 mL min−1 in the descending mode by using the biphasic solvent system methyl-ter-butylether, acetone, methanol and water (3:1:1:3, v/v/v/v). Trioctylmethylammonium chloride (Aliquat 336®) was used as the anion exchanger in the organic stationary phase and sodium iodide as the displacer in the aqueous mobile phase. From 5 g of crude extract of A. bracteolata, 45.5 mg, 77.2 mg and 35.1 mg of aristolochic acids I, II and IIIa were obtained respectively with purities greater than 95%.

Ethnopharmacoligical relevance Leaves of Crateva adansonii DC (Capparidaceae), a small bush found in Togo, are widely used in traditional medicine to cure infectious abscesses. Traditional healers of Lome harvest only budding leaves early in the morning, in specific area in order to prepare their drugs. Aim of the study The main goal was to validate the ancestral picking practices, and to assess the activity of C. adansonii medicine towards infectious abscesses. Materials and methods A phytochemical screening of various C. adansonii leaf samples was performed using an original HPTLC-densitometry protocol and major flavonoids were identified and quantified. C. adansonii samples were collected in different neighborhoods of Lome, at different harvesting-times and at different ages. Radical scavenging capacity, using DPPH assay, was used to quickly screen all extracts. Extracts were tested for anti- Staphylococcus aureus activity and anti-inflammatory effect on human primary keratinocytes infected by S. aureus . IL6, IL8 and TNFα expression and production were assessed by RT-PCR and ELISA assays. Results Using antioxidant activity as selection criteria, optimal extracts were obtained with budding leaves, collected at 5:00 am in Djidjole neighborhood. This extract showed the strongest anti-inflammatory effect on S. aureus -infected keratinocytes by reducing IL6, IL8 and TNFα expression and production. None of the extracts inhibited the growth of S. aureus . Conclusions Those results validate the traditional practices and the potential of C. adansonii as anti-inflammatory drug. Our findings suggest that traditional healers should add to C. adansonii leaves an antibacterial plant of Togo Pharmacopeia, in order to improve abscess healing.

Cranberry polyphenols are intensively studied for their anti-infectious and antioxidant properties. Nevertheless, in biofilm and infected-wound healing, the identity of active polyphenols still remains unclear. In order to identify active polyphenols, an innovative fractionation scheme based on Centrifugal Partition Chromatography (CPC) was developed. CPC is a support free liquid/liquid chromatographic technology used here for the first time to fractionate cranberry juice. The fractionation protocol involved 3 mains steps: firstly polyphenol and sugars separation; then polyphenols fractionation based of molecular weight and polarity, and finally CPC or on LH-20 resin. Following the second step, the 6 main fractions obtained were screened on Candida biofilm and toward infected wound. Fractions containing low molecular weight proanthocyanidins (Fr Ill and IV) and containing high molecular weight PAC (Fr V ad VI) exhibited the most interesting activities. Concerning Candida albicans biofilm a prophylactic effect was observed by prevention of adhesion. On infected wound, a wound-healing potential related to anti-inflammatory effect but not to antibacterial activity against Staphylococcus aureus was highlighted. These four active fractions were further purified using either CPC or LH-20 resin, to lead to almost 40 sub-fractions. Against fractions containing PACs of medium and high molecular weight exhibited the highest activity against adhesion step of C. albicans strains and infected wound healing. This work is a step further to understand mechanisms of action of cranberry polyphenols on C. albicans biofilm prevention and in infected wound healing.

Theme 4: Natural products as preventive and curative medicine for humans and animals Theme 4: Natural products as preventive and curative medicine for humans and animalsTheme 4: Natural products as preventive and curative medicine for humans and animals; Digestive strongyles are a serious handicap for sheep farming, due to production losses or associated veterinary costs. Meanwhile, the molecules currently available to control these parasites are no longer appropriate due to the emergence of resistant parasite populations but also because of the environmental impact of these molecules. The use of nutraceuticals, plants simultaneously presenting nutritional and medicinal qualities, could be an alternative solution to sustainable pest management. Lupine seed, Lupinus spp., is a protein crop used in animal farming. This plant also contains alkaloids that target nicotinic receptors [1], targets for anthelmintic drugs. These alkaloids provide toxic properties to the bitter ecotypes. The varieties used in animal feed legally contain less than 1.5% bitter seeds. Our study aims at validating and quantifying these properties through in vitro testing of seed extracts from alkaloid-rich or –poor varieties. Five varieties of sweet lupine (3 L. albus L. angustifolius, 1 L. luteus) and six bitter ecotypes (3 L. albus, 1 L. angustifolius, 1 L. luteus, 1 L. mutabilis), richer in alkaloids, were tested against H. contortus. Two L albus varieties, a sweet-one ENERGY and a bitter-one E063, exhibited the higher activity on H. contortus mobility. Chemical analyses revealed a higher alkaloid content in the alkaloid-rich (E063) (3.3% vs 0.04% in the alkaloid-poor) but a lower diversity than in the alkaloid-poor variety (ENERGY) (n=3 vs 5 respectively). Aqueous extracts of both varieties could significantly control infective larval stages and inhibited egg development. Extracted alkaloid fractions exhibited a stronger inhibitory effect, corroborating the working hypothesis, and could also control a multi-resistant isolate. These results are in favor of nutraceutical properties of lupin seed. Alkaloids of ENERGY variety exhibited original mechanism of action against cholinergic receptors, with low EC50.

Poster Session Wednesday; Antioxidative and wound healing properties of [i]Crateva adansonii[/i]. 9. Joint Natural Products Conference 2016

Poster Session Wednesday : Theme 5: Production and regulatory aspects of herbal preparations; Solid/liquid extraction as key step for quality assessment of commercial cranberry products using HPTLC-densitometry. 9. Joint Natural Products Conference 2016

Two heterodimers comprising anthraquinone and methylbenzoisocoumarin moieties (1 and 2) were isolated, together with emodin and physcion from the tubers of Pyrenacantha kaurabassana. The structures of 1 and 2 were established by NMR spectroscopy, including the analysis of a 2D INADEQUATE spectrum. On the basis of the data obtained, the structures that were previously proposed in the literature for these compounds were revised. Compounds 1 and 2 showed antibacterial activity against three different strains of Staphylococcus aureus. Compound 2 also showed bactericidal activity against Helicobacter pylori.