Infections hivernales et Médecines complémentaires (Prévention par stimulation du système immunitaire)

MONTPELLIER-BU Pharmacie (341722105) / SudocSudocFranceF

Natural Deep Eutectic Solvents as sustainable solvent for Suzuki-Miyaura cross- coupling reactions applied to imidazo-fused heterocycles

International audienc

Regiocontrolled functionalization of 2,3-dihalogenoimidazo[1,2-a] pyridines by Suzuki-Miyaura and Sonogashira cross-coupling reactions

International audienceAn efficient method for regiocontrolled functionalization of 2,3-dihalogenoimidazo[1,2-a] pyridine was developed. This sequence allowed the selective introduction of aryl, heteroaryl, alkyl and alkynyl substituents at both 2- and 3-positions, by using Suzuki-Miyaura and Sonogashira cross-coupling reactions. A library of compounds diversely substituted on 2- and 3-positions can be easily prepared from a common, stable and easily accessible starting material

Quality control of commercial cranberry products: HPTLC-densitometry a new deal

International audienceA fast quality control protocol based on reference BL-DMAC assay and High-performance thin-layer chromatography (HPTLC)-Densitometry was optimized for routine quality control of cranberry (Vaccinium macrocarpon) products. The sample preparation appeared as a key step to ensure a relevant comparison of products quality and biological data. Sequential solid/liquid extractions were required to fully extract polyphenols, regardless the extraction solvent chosen. The HPTLC-densitometry herein protocol used epicatechin, PAC-A2 and PAC-B2 as quality markers and densitometric measurements at 200 nm. The PAC-A2/Epicatechin ratio, obtained using HPTLC, appeared as an appropriate indicator of the quality of cranberry ingredient. Only two products, among the tested panel, exhibited a high quality cranberry-based ingredient using this criteria. UPLC-MS analyses coupled to multivariate analyses confirmed HPTLC-densitometry conclusions. This work highlighted the plural PAC composition of commercial products and the lack of standardization for cranberry-based products on the market, explaining the non-reproducibility of clinical trials

Solid/liquid extraction as key step for quality assessment of commercial cranberry products using HPTLC-densitometry

Poster Session Wednesday : Theme 5: Production and regulatory aspects of herbal preparationsSolid/liquid extraction as key step for quality assessment of commercial cranberry products using HPTLC-densitometry. 9. Joint Natural Products Conference 201

Cassia sieberiana root bark used in traditional medicine in Togo: Anthelmintic property against Haemonchus contortus and tannins composition

International audienceHelminth infections of livestock result in economic losses around the globe. The majority of the people in West Africa treats such infections with medicinal plants related to the local traditional medicine. In a previous ethnomedicinal survey carried out in the north of Togo, traditional healers frequently cited Cassia sieberiana DC to treat helminth infections. The aim of the present study was to validate the traditional application of C. sieberiana root bark as a dewormer and to analyse the metabolite composition in preparations with this activity. Two tannin-rich fractions (FrE14 and FrE15) obtained from ethyl acetate extract were submitted to UPLC-MS analysis. The anthelmintic activity of C. sieberiana extracts and tannins-rich fractions was investigated on the small ruminant parasite Haemonchus contortus using Larval Migration Inhibition tests. The ethyl acetate, butanol and aqueous extracts significantly disrupted larval migration of Haemonchus contortus L3 with inhibition of 30.3%, 22.2% and 26.5% respectively at 2.5 mg/mL, as compared to negative control. The two tannin-rich fractions, FrE14 and FrE15 presented larval migration inhibition of 6.5% and 20.7% respectively at the same concentration. From these two fractions, 28 flavan-3-ols were identified including 3 monomers (catechin, epicatechin and epiafzelechin), 22 dimers (7 homodimers and 15 heterodimers) as well as 3 newly described trimers consisting of (epi)afzelechin, (ent)cassiaflavan or (epi)guibourtidinol subunits

Domino 6-endo-dig Cyclization/Halogenation Reactions: Three-Component Synthesis of 1,3-Disubstituted 4-Haloimidazo[1,2-a:4,5-c′]dipyridines

International audienc

One-step preparative isolation of aristolochic acids by strong ion‐exchange centrifugal partition chromatography

Poster Session Monday : Theme 2: Sources of bioactive compoundsOne-step preparative isolation of aristolochic acids by strong ion‐exchange centrifugal partition chromatography. 9. Joint Natural Products Conference 201

Antioxidative and wound healing properties of Crateva adansonii DC

Leaves of Crateva adansonii DC, a small bush found in Togo, are widely used in traditional medicine to cure infectious abscess. Traditional healers harvest only young leaves and sprouts early in the morning in order to prepare their drugs. To validate this ancestral practice, we performed a phytochemical screening of various C. adansonii leaves samples collected in different places, at different time and at different ages. Using antioxidant activity as selection criteria, optimal extracts were obtained with sprout leaves, collected at 5:00 am in Djidjolé. Wound healing potential was then investigated for several extracts in vitro on keratinocytes stimulated by Staphylococcus aureus proteins. Anti-inflammatory activity was highlighted with flavonoids-rich extracts, especially against TNFa. Those results validate the traditional practices and the potential of C. adansonii as wound healing drug

Innovative bioguided fractionation of cranberry juice for Candida biofilm treatment and infected-wound 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