The metabolites from the coumarin class, present in tissues of plants belonging mainly to the Rutaceae and Apiaceae families, included compounds with high chemical diversity such as simple coumarins and furocoumarins. These health-promoting components are recognized for their valuable biological activities in herbal preparations but also for their phototoxic effects. In this work, a targeted liquid chromatography (LC) coupled with tandem mass spectrometry (MS2) was developed for the screening of 39 reference standards of coumarins and furocoumarins in essential oils and plant extracts. Chromatographic separation was accomplished on reversed phase column using water/acetonitrile as the mobile phase and detection was performed on a hybrid QqQ/linear ion trap spectrometer fitted with an atmospheric pressure chemical ionization (APCI) source operating in positive ion mode. This analytical approach was applied to investigate the coumarin compositions of fruit essential oils and methanolic extracts obtained from separated parts (fruit, leaf, stem, trunk, and root) of Zanthoxylum zanthoxyloides. Ten coumarins and six furanocoumarins were reported in this species and data analyses were used to assess the suitability of these compounds to the metabolomics-based differentiation of plant organs. The quantification criteria of the metabolites in extract samples included linearity, limit of quantification, limit of detection, and matrix effect were validated. As reported for other species of the Rutaceae family, the concentration of coumarins was drastically higher in Z. zanthoxyloides fruits than in other plant organs.

Flavonoids are a large group of phenolic secondary metabolites having a wide range of biochemical and pharmacological effects. In this work, a targeted liquid chromatography (LC) coupled with tandem mass spectrometry (MS 2) was used to characterize the flavonoid compositions of methanolic plant extracts from separated parts (fruits, leaves, stems, trunk barks, and root barks) of Zanthoxylum zanthoxyloides. Nine flavonoids were reported in this species, including three flavanones, five flavonols and one flavone. Quantitative analysis of flavonoid profiles from Z. zanthoxyloides extracts is useful to a better understanding of the pattern and distribution of metabolites in extract samples. The concentrations of two glycosylated flavanones (neohesperidin and hesperidin) and one flavonol (quercetin) were higher in root and trunk samples compared to fruit samples. These compounds were reported in small amounts in the stem and leaf samples. In contrast, four flavonols (hyperoside, quercetin-3-O-glucopyranoside, datiscin and quercitrin) were present in significant levels only in the leaf extracts. The presence of glycosylated flavanone (eriocitrin) has been reported only in fruit extract. The antioxidant properties of different extracts were tested regarding their scavenging activities on ABTS •+ radical. Leaf and trunk bark extracts exhibited antioxidant activities, while the extracts obtained from other organs (fruits, stems, and root barks) showed low antioxidant properties.

The chemical diversity of Zanthoxylum zanthoxyloides growing wild in Senegal was studied according to volatile compound classes, plant organs and sample locations. The composition of fruit essential oil was investigated using an original targeted approach based on the combination of gas chromatography (GC) and liquid chromatography (LC) both coupled with mass spectrometry (MS). The volatile composition of Z. zanthoxyloides fruits exhibited relative high amounts of hydrocarbon monoterpenes (24.3 - 55.8%) and non-terpenic oxygenated compounds (34.5 - 63.1%). The main components were (E)-β-ocimene (12.1 - 39%), octyl acetate (11.6 - 21.8%) and decanol (9.7 - 15.4%). The GC and GC/MS profiling of fruit essential oils showed a chemical variability according to geographical locations of plant material. The LC/MS/MS analysis of fruit oils allowed the detection of seven coumarins in trace content. The chemical composition of fruit essential oils was compared with volatile fractions of leaves and barks (root and trunk) from the same plant station. Hexadecanoic acid, germacrene D and decanal were identified as the major constituents of leaves whereas the barks (root and trunk) were dominated by pellitorine (85.8% and 57%, respectively), an atypic linear compound with amide group. The fruit essential oil exhibited interesting antimicrobial activities against Staphylococcus aureus and Candida albicans, particularly the alcohol fraction of the oil.

SummaryUse of medicinal plants is common and widespread throughout Africa, including in Senegal. Because efficacy has been demonstrated, public policies have been instituted that have allowed plant-based therapies to have an important role in general primary care. However, little is known about the cutaneous safety of many plant-based therapies. In this 6-month prospective study all cases of dermatitis induced or aggravated by exclusive use of medicinal plants were evaluated via skin allergy testing. The results were classified and compared with the available literature. Forty-three cases of plant-therapy-associated cutaneous reactions were identified, including worsening of existing conditions (56%), recurrence of a previously resolved condition (16%) and new dermatitis arising spontaneously (28%). In the cases where the condition was new, generalized exfoliative dermatitis occurred in 42% of cases with an average time of onset of 9 days. Specific plants were identified in 65% of cases and included 18 varieties. The frequency and severity of plant-induced cutaneous reactions should be the basis for the creation of a phytovigilance programme and re-evaluation of how traditional medicine is used in the general population. When irritation occurs, identification of the responsible plant and allergy testing should be the first steps towards relieving symptoms.In Africa, many plants are used empirically in traditional medicine. According to the World Health Organization, plantbased therapies represent a first-line medical recourse for more than 80% of people across all social classes in many African countries. This is due to the accessibility and low cost of plant-based medicine, along with advertisements in the media by an increasing number of traditional practitioners. However, these practitioners are sometimes illiterate and incompetent. The current cultural environment promotes self-medication and/or polymedication.Often called traditional phytotherapy, plant-based therapies can be delivered via either topical or oral routes. Topical delivery consists of direct application of the plant onto the skin, while the oral route encompasses ingestion of a liquid maceration of one or several plants. The benefits of plantbased therapies have been demonstrated; various administrative policies currently ensure that phytotherapy is an important component of primary-care medicine in Africa. However, the potential for harmful effects remains largely unknown by the general population, prescribers, and health and political authorities.Many dermatological afflictions diseases arise from or are exacerbated by the inappropriate and abusive use of these plants. The condition may be life-threatening when it is an erythroderma (exfoliative dermatitis) or leads to synechiae of ocular and genital mucous membranes. Despite the current use of hundreds of plants in traditional medicine, very few toxicological studies have been conducted in research laboratories. The present study was performed to evaluate the cutaneous safety of several com...

Screening of flavonoid compounds in fruit, leaf, stem and root bark extracts of Z. leprieurii was achieved by liquid chromatography (LC) coupled with tandem mass spectrometry (MS2). Among the 186 reference compounds tested, four flavonoids were identified in one or other of the organ extracts from each plant (fruit, leaf, root barks and stem): neodiosmin and hesperidin were identified in all extracts. The presence of datiscin was reported only in leaves while that of rutin was identified in fruits and leaves. Of these four flavonoids, three (neodiosmin, datiscin and rutin) are detected for the first time in Z. leprieurii. The antioxidant properties of different extracts were tested regarding their scavenging activities on ABTS•+ radical. Fruit, leaf and stem extracts had low antioxidant potential and root bark extracts exhibited very low antioxidant activity. Keywords: Zanthoxylum leprieurii, flavonoids, LC-MS/MS and antioxidant activity.

Members of the genus Eucalyptus are potential sources of number of commercial essential oils and aromachemicals. In present study, the essential oils isolated by hydrodistillation from the leaves of Eucalyptus alba were analyzed by GC-FID and GC-MS. Essential oil yields ranged from 2.41 to 4.35%. In total 18 constituents were identified, accounting for 99.0 to 99.7% of the total compositions. 1,8-cineole was present in all samples as the major component (76.5-88.1%). In addition to this compound, others that were found including limonene (3.8–8.6%), α-terpineol (1.4–2.8%), globulol (1.3–6.3%) and α-pinene (1.5–1.8%). The essential oil showed a strong antibacterial activity against S. aureus ATCC 29213 which is translated by an MIC of 1.25 mg/mL and good activity against E. coli ATCC 25922 (6.25 mg/mL) and E. faecalis ATCC 29212 (6.25 mg/mL). To our knowledge, our study is the first report of E. alba essential oils characterized by a high 1,8-cineole content (>76.5%). They may have potential applications in food and pharmaceutical products. Keywords: Eucalyptus alba, essential oils, antibacterial activity, 1,8-cineole and GC-SM

La valorisation des ressources locales constitue un impératif afin d'atteindre des objectifs de développement durable. Cette étude a consisté à évaluer les caractéristiques physiques, chimiques et minéralogiques d'une argile provenant de Mbodiène (Sénégal), l'attapulgite, comparativement avec un médicament antidiarrhéique, constitué d'attapulgite, dénommé Actapulgite®. L'échantillon d'attapulgite brute a été purifié avec une solution de HNO 3 1M. Une étude morphologique effectuée par visualisation à la Microscopie Electronique à Balayage a montré pour les deux argiles étudiées, une structure fibreuse caractéristique de la palygorskite, représentant le minéral dominant. L'analyse chimique par la spectrométrie à fluorescence X a donné pour l'attapulgite purifiée : 65,69% Si,

Cette étude avait pour objectif de faire le point sur la composition chimique et les activités biologiques de G. senegalensis, une plante médicinale  largement utilisée en Afrique par les guérisseurs traditionnels pour le  traitement de divers troubles. La plupart de ces études chimiques ont porté sur le criblage phytochimique des extraits de feuilles, de racines, de tiges et de galles. Elles ont montré la présence d'hydrates de carbone, de  stéroïdes, de saponines, de flavonoïdes, d’alcaloïdes, de tanins, de  saponines, de glycosides cardiaques, de coumarines, d’anthraquinones, d’acide ascorbique, d’hétérosides cardiotoniques, de cyanogènes et de terpénoïdes. Les potentialités thérapeutiques des extraits de G.  senegalensis rapportées dans plusieurs travaux scientifiques ont porté sur les activités antibactériennes, antitussives, antidiarrhéiques, cytotoxiques, anti-inflammatoires antipaludiques, antitrypanosomiques,  antihelminthiques, antivirales et antioxydantes. Des études de toxicité sur ces extraits ont été aussi réalisées. Ainsi, des études de caractérisation chimique (variabilité chimique), de formulation galénique et aussi de toxicité clinique sur G. senegalensis doivent être menées afin de mettre en place des produits de phytothérapie moderne.Mots clés: Phytochimie, pharmacologie, feuilles, Guiera senegalensis. English Title: Review on the chemical composition and biological activities of Guiera senegalensis J.F. Gmel. (Combretaceae)The aim of this study was to review the chemical composition and biological activities of G. senegalensis, a medicinal plant widely used in Africa by  traditional healers for the treatment of various disorders. Most of these chemical studies have focused on the phytochemical screening of leaf, root, stem and gall extracts. They showed the presence of carbohydrate,  steroids, saponins, flavonoids, alkaloids, tannins, saponins, cardiac  glycosides, coumarins, anthraquinones, ascorbic acid, cardiotonic  glycosides, cyanogens and terpenoids. The therapeutic potentialities of extracts of G. senegalensis reported in several scientific studies have  focused on antibacterial, antitussive, antidiarrheal, cytotoxic, anti-inflammatory, antimicrobial, antitrypanosomal, anthelmintic, antiviral and antioxidant activities. Toxicity studies on these extracts have also been carried out. Thus, chemical characterization studies (chemical variability), galenic formulation and clinical toxicity studies on G. senegalensis must be carried out in order to implement modern phytotherapy products.Keywords: Phytochemistry, pharmacology, leaves, Guiera senegalensis.