Rosmarinic Acid and Its Methyl Ester as Antimicrobial Components of the Hydromethanolic Extract of Hyptis atrorubens

Primary biological examination of four extracts of the leaves and stems of Hyptis atrorubens Poit. (Lamiaceae), a plant species used as an antimicrobial agent in Guadeloupe, allowed us to select the hydromethanolic extract of the stems for further studies. It was tested against 46 microorganisms in vitro. It was active against 29 microorganisms. The best antibacterial activity was found against bacteria, mostly Gram-positive ones. Bioautography enabled the isolation and identification of four antibacterial compounds from this plant: rosmarinic acid, methyl rosmarinate, isoquercetin, and hyperoside. The MIC and MBC values of these compounds and their combinations were determined against eight pathogenic bacteria. The best inhibitory and bactericidal activity was found for methyl rosmarinate (0.3 mg/mL). Nevertheless, the bactericidal power of rosmarinic acid was much faster in the time kill study. Synergistic effects were found when combining the active compounds. Finally, the inhibitory effects of the compounds were evaluated on the bacterial growth phases at two different temperatures. Our study demonstrated for the first time antimicrobial activity of Hyptis atrorubens with identification of the active compounds. It supports its traditional use in French West Indies. Although its active compounds need to be further evaluated in vivo, this work emphasizes plants as potent sources of new antimicrobial agents when resistance to antibiotics increases dramatically

Research and development of antifungal extracts from the guadelupian flora : phytochemical, pharmacological studies and pharmaceutical formulation

Malgré l’arsenal antifongique existant aujourd’hui, les mycoses superficielles sont en constante progression de par le monde et notamment dans le bassin caribéen. Nous nous sommes focalisés sur les pathologies qui posent, en Guadeloupe, de nombreux problèmes de résistance ou de rechute vis-à-vis des antifongiques actuels, à savoir : les dermatophyties, le Pityriasis versicolor (Malassezia sp.), les candidoses et les scytalidioses. Suite à ce constat, nous nous sommes tournés vers la flore guadeloupéenne où ont été sélectionnées dix plantes sur des critères ethnobotaniques, chimiotaxonomiques ou encore d’observations naturalistes avec un double objectif : trouver de nouveaux extraits antifongiques d’une part et, d’autre part, étudier leur composition et vérifier leur innocuité. Le screening antifongique in vitro des extraits c-hexane, EtOH et EtOH/eau (1:1, v/v) a été réalisé vis-à-vis de 4 dermatophytes, 1 Malassezia sp., 5 Candida spp. et 1 Scytalidium sp. Les extraits ont également été testés vis-à-vis d’un autre pathogène, Pneumocystis jirovecii responsable de la pneumocystose pulmonaire. Quatre plantes : Bursera simaruba, Cedrela odorata, Enterolobium cyclocarpum et Pluchea carolinensis ont été retenues afin de définir leurs cytotoxicités puis de procéder à l’isolement des composés responsables de leur activité antifongique par bioguidage. Cedrela odorata a montré une activité significative vis-à-vis de Pneumocystis jirovecii due en partie à la (+)-catéchine. Concernant les mycoses superficielles, Bursera simaruba et Cedrela odorata présentent une activité due à une synergie de composés non identifiés par bioguidage alors que Pluchea carolinensis et Enterolobium cyclocarpum doivent respectivement leurs activités à des flavonoïdes sulfatés et à des saponosides triterpéniques. Faisant suite à cette étude phytochimique et pharmacologique, la formulation des extraits sous forme de gels et vernis a été développée. Ainsi, cette étude permet d’apporter une réponse originale et efficace aux pathologies ciblées.Despite the existing arsenal of antifungals today, superficial fungal infections have increased over the world and especially in the Caribbean basin. We focused our work on diseases that pose, in Guadeloupe, many problems of resistance or recurence towards current antifungals : dermatophytosis, Pityriasis versicolor (Malassezia sp.), Candidosis and Scytalidiosis. Following this observation, we were interested in the flora of Guadeloupe where ten plants were selected on natural observation, ethnobotanical or chemotaxonomical criteria with a dual purpose: to find new antifungal extracts on the one hand, and secondly, to study their composition and verify their safety. The in vitro screening of c-hexane, EtOH and EtOH/water (1:1, v/v) extracts, was made towards four dermatophytes, one Malassezia sp., five Candida spp. and one Scytalidium sp. The extracts were also tested on another pathogen, Pneumocystis jirovecii which is responsible of pneumonia. Four plants: Bursera simaruba, Cedrela odorata, Enterolobium cyclocarpum and Pluchea carolinensis were chosen to define their cytotoxicities and then we proceed to the isolation of active compounds by bioguiding. Cedrela odorata showed significant activity on Pneumocystis jirovecii and (+)-catechin was found to be partly responsible of this activity. Concerning the research on the superficial mycoses, Bursera simaruba and Cedrela odorata’s activities were due to a synergy of compounds unidentified by bioguiding while Pluchea carolinensis and Enterolobium cyclocarpum owe their activities to sulfated flavonoids and triterpene saponins, respectively. Following to these phytochemical and pharmacological studies, the drug formulation of the extracts has been developed. Thus, this study could be an original and effective response to the targeted disease

Recherche et développement d'extraits antifongiques issus de la flore guadeloupéenne : caractérisations phytochimiques, pharmacologiques et formulation

Despite the existing arsenal of antifungals today, superficial fungal infections have increased over the world and especially in the Caribbean basin. We focused our work on diseases that pose, in Guadeloupe, many problems of resistance or recurence towards current antifungals : dermatophytosis, Pityriasis versicolor (Malassezia sp.), Candidosis and Scytalidiosis. Following this observation, we were interested in the flora of Guadeloupe where ten plants were selected on natural observation, ethnobotanical or chemotaxonomical criteria with a dual purpose: to find new antifungal extracts on the one hand, and secondly, to study their composition and verify their safety. The in vitro screening of c-hexane, EtOH and EtOH/water (1:1, v/v) extracts, was made towards four dermatophytes, one Malassezia sp., five Candida spp. and one Scytalidium sp. The extracts were also tested on another pathogen, Pneumocystis jirovecii which is responsible of pneumonia. Four plants: Bursera simaruba, Cedrela odorata, Enterolobium cyclocarpum and Pluchea carolinensis were chosen to define their cytotoxicities and then we proceed to the isolation of active compounds by bioguiding. Cedrela odorata showed significant activity on Pneumocystis jirovecii and (+)-catechin was found to be partly responsible of this activity. Concerning the research on the superficial mycoses, Bursera simaruba and Cedrela odorata’s activities were due to a synergy of compounds unidentified by bioguiding while Pluchea carolinensis and Enterolobium cyclocarpum owe their activities to sulfated flavonoids and triterpene saponins, respectively. Following to these phytochemical and pharmacological studies, the drug formulation of the extracts has been developed. Thus, this study could be an original and effective response to the targeted disease.Malgré l’arsenal antifongique existant aujourd’hui, les mycoses superficielles sont en constante progression de par le monde et notamment dans le bassin caribéen. Nous nous sommes focalisés sur les pathologies qui posent, en Guadeloupe, de nombreux problèmes de résistance ou de rechute vis-à-vis des antifongiques actuels, à savoir : les dermatophyties, le Pityriasis versicolor (Malassezia sp.), les candidoses et les scytalidioses. Suite à ce constat, nous nous sommes tournés vers la flore guadeloupéenne où ont été sélectionnées dix plantes sur des critères ethnobotaniques, chimiotaxonomiques ou encore d’observations naturalistes avec un double objectif : trouver de nouveaux extraits antifongiques d’une part et, d’autre part, étudier leur composition et vérifier leur innocuité. Le screening antifongique in vitro des extraits c-hexane, EtOH et EtOH/eau (1:1, v/v) a été réalisé vis-à-vis de 4 dermatophytes, 1 Malassezia sp., 5 Candida spp. et 1 Scytalidium sp. Les extraits ont également été testés vis-à-vis d’un autre pathogène, Pneumocystis jirovecii responsable de la pneumocystose pulmonaire. Quatre plantes : Bursera simaruba, Cedrela odorata, Enterolobium cyclocarpum et Pluchea carolinensis ont été retenues afin de définir leurs cytotoxicités puis de procéder à l’isolement des composés responsables de leur activité antifongique par bioguidage. Cedrela odorata a montré une activité significative vis-à-vis de Pneumocystis jirovecii due en partie à la (+)-catéchine. Concernant les mycoses superficielles, Bursera simaruba et Cedrela odorata présentent une activité due à une synergie de composés non identifiés par bioguidage alors que Pluchea carolinensis et Enterolobium cyclocarpum doivent respectivement leurs activités à des flavonoïdes sulfatés et à des saponosides triterpéniques. Faisant suite à cette étude phytochimique et pharmacologique, la formulation des extraits sous forme de gels et vernis a été développée. Ainsi, cette étude permet d’apporter une réponse originale et efficace aux pathologies ciblées

Antifungal Activity of 10 Guadeloupean Plants.

International audienceScreening of the antifungal activities of ten Guadeloupean plants was undertaken to find new extracts and formulations against superficial mycoses such as onychomycosis, athlete's foot, Pityriasis versicolor, as well as the deep fungal infection Pneumocystis pneumonia. For the first time, the CMI of these plant extracts [cyclohexane, ethanol and ethanol/water (1:1, v/v)] was determined against five dermatophytes, five Candida species, Scytalidium dimidiatum, a Malassezia sp. strain and Pneumocystis carinii. Cytotoxicity tests of the most active extracts were also performed on an HaCat keratinocyte cell line. Results suggest that the extracts of Bursera simaruba, Cedrela odorata, Enterolobium cyclocarpum and Pluchea carolinensis have interesting activities and could be good candidates for developing antifungal formulations. Copyright © 2012 John Wiley & Sons, Ltd