Yahia Cherrah

Nigella sativa inhibits intestinal glucose absorption and improves glucose tolerance in rats.

AIM OF THE STUDY Nigella sativa L. (Ranunculaceae) seeds have been used traditionally for centuries, notably for treating diabetes. MATERIALS AND METHODS We studied the effects of the crude aqueous extract of Nigella sativa seeds on intestinal glucose absorption in vitro using a short-circuit current technique and in vivo using an oral glucose tolerance test. RESULTS The aqueous extract of Nigella sativa (0.1 pg/ml to 100 ng/ml) exerted dose-dependent inhibition of sodium-dependent glucose transport across isolated rat jejunum. Maximal inhibition exceeded 80% and IC50 was close to 10 pg/ml. An oral glucose tolerance test was carried out in rats after the initial dose and after a 6-week treatment of Nigella sativa (2 g/(kg day)), and compared to metformin (300 mg/(kg day)). Chronic Nigella sativa treatment improved glucose tolerance as efficiently as metformin. Nigella sativa and metformin also reduced body weight without any toxic effect. CONCLUSIONS To our knowledge, this is the first demonstration that Nigella sativa directly inhibits the electrogenic intestinal absorption of glucose in vitro. Together with the observed improvement of glucose tolerance and body weight in rats after chronic oral administration in vivo, these effects further validate the traditional use of Nigella sativa seeds against diabetes.

Comparative Study on the Medicinal Plants Most Recommended by Traditional Practitioners in Morocco and Canada

ABSTRACT An ethnopharmacological survey was used to compare the medicinal plants most frequently recommended by herbalists, naturopaths, and other traditional practitioners in Moroccan and Canadian socio-economical settings. Striking differences in traditional pharmacopoeias were noted between Morocco and the Canadian province of Quebec, with only one plant, garlic, on both lists of the top 20 most frequently recommended plants. Therapeutic indications, however, showed more similarities with rosemary, lavender, oregano, and white mugwort being recommended against gastrointestinal upset/liver ailments in Morocco, as compared with chamomile, milk thistle, linden and dandelion for similar indications in Quebec. Central nervous system disorders were the second most important indications for medicinal plants (including St. Johns wort, chamomile, ginkgo, valerian, and linden) in Quebec as compared with cold/flu/cough for plants indicated in the Moroccan survey (including oregano, lavender, black cumin, Syrian rue and white mugwort). Other common therapeutic indications included circulatory and renal problems in both surveys. In Morocco, native or Mediterranean plants form the greater part of the most commonly recommended herbal medicines, but in Quebec almost half of the recommended medicinal plants originate in Europe and only a quarter of the plants are native to eastern Canada. Similar findings were obtained when survey respondents were asked specifically about anti-diabetic plants. Only fenugreek was among the top ten plants indicated for diabetes in both Morocco and Quebec. The Mediterranean plants used in Morocco could possibly contain phytochemical principles active in several therapeutic indications common to North African and eastern Canadian socio-economical settings, particularly in diabetes.

Sedative and Hypnotic Activities of the Methanolic and Aqueous Extracts of Lavandula officinalis from Morocco

We evaluate the sedative and hypnotic activities of the methanolic and aqueous extract of Lavandula officinalis L. on central nervous system (CNS). In this study, the effect of the methanolic and aqueous extracts of this plant was investigated in a battery of behavioural models in mice. Stems and flowers of Lavandula officinalis L. have several therapeutic applications in folk medicine in curing or managing a wide range of diseases, including insomnia. The methanolic extract produced significant sedative effect at the doses of 200, 400, and 600 mg/kg (by oral route), compared to reference substance diazepam (DZP), and an hypnotic effect at the doses of 800 and 1000 mg/kg while the treatment of mice with the aqueous extract at the doses of 200 and 400 mg/kg via oral pathway significantly reduced in both the reestablishment time and number of head dips during the traction and hole-board tests. In conclusion, these results suggest that the methanolic and aqueous extracts of Lavandula officinalis possess potent sedative and hypnotic activities, which supported its therapeutic use for insomnia.

In Vivo Potential Anti-Inflammatory Activity of Melissa officinalis L. Essential Oil

Melissa officinalis L. (Lamiaceae) had been reported in traditional Moroccan medicine to exhibit calming, antispasmodic, and strengthening heart effects. Therefore, this study is aimed at determining the anti-inflammatory activities of M. officinalis L. leaves. The effect of the essential oil of the leaves of this plant was investigated for anti-inflammatory properties by using carrageenan and experimental trauma-induced hind paw edema in rats. The essential oil extracted from leaves by hydrodistillation was characterized by means of gas chromatography-mass spectrometry (GC-MS). M. officinalis contained Nerol (30.44%), Citral (27.03%), Isopulegol (22.02%), Caryophyllene (2.29%), Caryophyllene oxide (1.24%), and Citronella (1.06%). Anti-inflammatory properties of oral administration of essential oil at the doses of 200, 400 mg/kg p.o., respectively, showed significant reduction and inhibition of edema with 61.76% and 70.58%, respectively, (P < 0.001) induced by carrageenan at 6 h when compared with control and standard drug (Indomethacin). On experimental trauma, M. officinalis L. essential oil showed pronounced reduction and inhibition of edema induced by carrageenan at 6 h at 200 and 400 mg/kg with 91.66% and 94.44%, respectively (P < 0.001). We can conclude that the essential oil of M. officinalis L. possesses potential anti-inflammatory activities, supporting the traditional application of this plant in treating various diseases associated with inflammation and pain.

Potentiometric sensor for hydroxyzine determination

A new polymeric membrane electrode has been developed for the determination of hydroxyzine. The electrode was constructed by solubilizing the hydroxyzine silicotungstate ion pair into a polyvinylchloride matrix plasticized by nitrophenyloctylether. The electrode exhibited a near-Nernstian response (57 mV/decade) in the concentration range comprised between 1×10−2 M and 6×10−7 M with a lower limit of detection of 2.5×10−7 M. The electrode response was not sensitive to pH changes between 2.8 and 6.9 and not affected by possible interfering species such as cetirizine and pharmaceutical excipients. The electrode was successfully applied to the determination of hydroxyzine in pharmaceuticals and in a dissolution profile study of tablets. The results were validated by comparison with LC and spectrophotometric assays according to the USP Pharmacopoeia methods.

Determination of binary polymorphic mixtures of fluconazole using near infrared spectroscopy and X-ray powder diffraction: A comparative study based on the pre-validation stage results

The aim of the present study was to develop near infrared (NIR) and X-ray powder diffraction methods (XRPD) able to determine pure crystalline form II of fluconazole in a binary polymorphic mixtures containing forms II and III. In order to give a first performance estimation of both methods, these latters were pre-validated using accuracy profiles, a statistical approach based on β-expectation tolerance intervals. Both methods showed a good trueness, precision and accuracy and their β-expectation tolerance intervals were fully included within the acceptance limits. The comparative study was carried out using statistical analysis based on the work of Bland and Altman. A good agreement between the two methods was demonstrated indicating the interchangeability of NIR method with XRPD method.

Activité antifongique de l’acide oléique et des huiles essentielles de Thymus saturejoides L. et de Mentha pulegium L., comparée aux antifongiques dans les dermatoses mycosiques

RésuméL’activité antifongique in vitro de deux huiles essentielles (HE) de plantes aromatiques et médicinales (PAM) (thym et menthe pouliot) et de l’acide oléique a été évaluée contre 15 souches de différentes espèces de dermatophytes isolées de diverses dermatophyties traitées à l’Hôpital d’enfants de Rabat dont Trichophyton rubrum (5 isolats), Trichophyton mentagrophytes (4 isolats) et Microsporum canis (4 isolats) (Microsporum gypseum et Epidermophyton floccosum sont issues de notre collection mycologique) et 7 levures dont 4 de Candida albicans et 3 de Malassezia sp. Cette activité a été comparée à celle de la griséofulvine, le kétoconazole, l’isoconazole nitrate et le sulfate de polymyxine B. Les CMI obtenues avec les HE sur les agents responsables de mycoses sont similaires à celles qui sont obtenus avec les imidazolés. L’acide oléique exerce une action fongistatique sur les dermatophytes sensibles tels T. rubrum, E. floccosum à des concentrations allant de 150–200 μg/ml. Cependant, les dermatophytes telluriques et zoophiles sont résistants. Les levures ne sont pas inhibées par l’acide oléique. La polymyxine B exerce une action fongitoxique importante sur Malassezia sp. et plusieurs dermatophytes. Pour le C. albicans, la sensibilité est variable.Ces résultats permettent d’entrevoir que les HE des PAM et l’acide oléique peuvent constituer une solution alternative valable aux agents antifongique dans la lutte contre les dermatoses mycosiques.AbstractThe antifungal activity in vitro of two essential oils of Medicinal Aromatic Plants (PAM’s) (thyme and mint pouliot) and oleic acid was evaluated against 15 stumps of different species of isolated dermatophytes in a variety of dermatophytosis affections among different consultants at the children’s hospital of Rabat including Trichophyton rubrum (5 isolates), Trichophyton mentagrophytes (4 isolates) and Microsporum canis (4 isolates), (Microsporum gypseum and Epidermophyton floccosum were taken from our mycological collection) and 7 yeasts among which are 4 Candida albicans as well as 3 of Malassezia spp. This activity was compared with that of the griseofulvin, the ketoconazole, the isoconazole nitrate and the sulfate polymyxine B.MIC obtained in essential oil on agents responsible for mycoses are almost similar to those obtained with imidazoles. Oleic acid exerts fungistatic action on sensitive dermatophytes such as (T. rubrum, E. floccosum) with concentrations between 150–200 μg/ml. However, telluric and zoophilic dermatophytes are resistant. Yeasts are not inhibited by oleic acid. The polymyxine B exerts an important fungitoxic action on Malassezia spp. and several dermatophytes. For Candida albicans, sensitivity is variable. These results allow to foresee that in essential oil of MAP and oleic acid can constitute a valid alternative to antifungal agents in the fight against mycotic dermatoses.

Toxicity and Psychotropic Activity of Essential Oils of Rosmarinus officinalis and Lavandula officinalis from Morocco

Abstract Leaves of Rosmarinus officinalis and the flowers of Lavandula officinalis have been used as medicine for treatment of nervous disorders, in traditional Moroccan medicine. We evaluate the central nervous system psychotropic effects of the essential oil from the leaves of R. officinalis and the flowers of L. officinalis using a battery of comportamental psychopharmacology tests. The essential oil extracted by hydrodistillation were characterized by means of GC-MS. R. officinalis contained α-pinene (15.82 %), camphene (6.80 %), β-pinene (4.75 %), myrcene (1.70 %), p-cymene (2.16 %), 1,8-cineole (50.49 %), camphor (11.61 %), borneol (2.58 %), and borneol acetate (2.08 %). However, lavender oil contains nine constituents, among which 1,8-cineole (5.30 %), linalool (44.67 %), camphor (6.02 %) and linalyl acetate (42.00 %) were identified. The intraperitonial administration in mice of essential oil from L. officinalis at 300 and 600 mg/kg i.p. induces strong sedative effects compared to reference substance diazepam in mice, and an hypnotic effects at doses 1000 and 1500 mg/kg. However, the essential oil extracted from R. officinalis at the doses 50 and 100 mg/kg, produced no sedative activity significant on the central nervous system.

Activité antiinflammatoire deZygophyllum gaetulum

RésuméZygophyllumgaetulum Emberger & Maire est un sous-arbrisseau des steppes désertiques du sud du Maroc. Utilisé traditionnellement comme anti-inflammatoire antidiabétique et antispasmodique, il est proposé dans la présente étude d’en évaluer et d’en confirmer l’activité anti-inflammatoire chez l’animal. L’extrait a été préparé selon les méthodes traditionnelles, l’étude a été réalisée sur des rats Wistar des deux sexes âgés de 2 à 3 mois et pesant 200–300 grammes. Le lot essai traité oralement par l’extrait deZygophyllum gaetulum (50 mg/kg) a montré une inhibition de l’œdème induit par la carragénine selon la méthode de Winteret al. [16].AbstractZygophyllumgaetulum Emberger & Maire grows in southern Morocco. It has been used as an anti-inflammatory, antidiabetic and antispasmodic medicinal plant. The present study was carried out to confirm the anti-inflammatory effect ofZygophyllum gaetulum. Airdried and powdered aerial parts were extracted following the methods of traditional healers. Wistar albino rats of both sexes, weighing 200–300g and aged 2–3 months, were used. The rats were housed under standard environmental conditions. Animals treated withZygophyllum gaetulum extract (500 mg/kg by mouth) showed oedema inhibition in all phases of the experiment, especially the final phase. The percentage of inhibition at 1 hr 30 min and 3 hrs was significant.

Étude de l’activité des huiles essentielles de plantes aromatiques à propriétés antifongiques sur les différentes étapes du développement des dermatophytes

Résumé:Le travail que nous avons réalisé a été consacré à l’étude de l’activité fongitoxique (action fongistatique et fongicide) des huiles essentielles sur la germination, la croissance mycélienne et la sporulation des dermatophytes responsables de multiples mycoses chez l’homme.Dans l’ensemble, les trois huiles essentielles testées de plantes aromatiques et médicinales: thym (Thymus saturejoïdes L.), menthe pouliot (Menthe pulegium L.) et romarin (Rosmarinus officinalis L.) présentent des activités inhibitrices sur la germination des spores ou des arthrospores de tous les dermatophytes testés à des concentrations allant de 0,001 à 4 %. Cette action a été plus forte sur les souches fongiques anthropophiles et avec de moindres concentrations.Le degré d’inhibition des huiles essentielles testées sur la croissance mycélienne est différent que celui qui est exercé sur la germination. En effet, avec les proportions d’huiles essentielles correspondant aux concentrations minimales d’inhibition sur le développement mycélien, il suffit de 1/10 à 1/100 de cette concentration pour inhiber la germination. Néanmoins, leur action sur la sporulation est plutôt favorisante. Dans tous les cas, l’inhibition est liée à une inhibition de la croissance mycélienne notamment avec les concentrations élevées en huile essentielle. Ainsi, selon leurs activités sur les dermatophytes, nos essences ont été classées dans l’ordre décroissant suivant: thym > menthe pouliot > romarin. Selon leur sensibilité, les dermatophytes étudiés peuvent être classés selon l’ordre décroissant suivant: M. gypseum > M. nanum > M. canis > T. mentagrophytes > T. concentricum > T. rubrum > T. schoenleinii > E. floccosum.Abstract:The present work is dedicated to the study of fungitoxic activity (fungistatic and fungicidal action) of essential oils on the germination, mycelial growth and sporulation of dermatophytes responsible for different cases of mycoses among humans. On the whole, the essential oil of aromatic and medicinal plants such as thyme (Thymus saturejoïdes L.), European pennyroyal (Menthe pulegium L.) and rosemary (Rosmarinus officinalis L.), show inhibitory activities on the germination of spore or arthrospores of all the dermatophytes tested with concentrations ranging from 0.001 to 4%. This action was stronger on anthropophilic fungal strains and at lower concentrations. The degree of inhibition of the essential oils tested on mycelial growth was different from the one exerted on germination. In fact, with proportions of essential oils corresponding to MIC (Minimal Inhibitory Concentration) on mycelial development, only 1/10 to 1/100 of this concentration was sufficient to inhibit germination. Nevertheless, their action on sporulation was rather encouraging. According to their activities on dermatophytes, essences tested were arranged in decreasing order, as follows: thyme > European pennyroyal > rosemary. According to their sensitivity, the studied dermatophytes could be classified in the following decreasing order: M. gypseum > M. nanum > M. canis > T. mentagrophytes > T. concentricum > T. rubrum > T. schoenléinii > E. floccosum.