Nadjib Mohammed Rahmoun

Purpose The use of phytotherapy is common worldwide and especially in Algeria. This practice was transmitted orally and ritually to treat chronic diseases. Safe extracts of edible plants can provide a resource of structurally diverse molecules that can effectively interfere with multifactorial diseases, such as diabetes mellitus. The objective of this work is to study the biochemical parameters of diabetic populations who consume medicinal plants. Methods This study involved 100 T2D subjects, recruited over a five-month period via a questionnaire containing anthropometric information: sex, age, age of diabetes, type of diabetes, plants consumed. Recruited patients were recalled for further examination of the biochemical record (fasting glucose, glycated hemoglobin, total cholesterol, triglycerides, creatinine, ASL and ASP). Results We found that diabetic patient associated with prescribed medical treatment uses the medicinal plants. This use is strongly predominant by women in both populations with 76% of them using herbal medicine. 58% of diabetics under herbal medicine had slightly unbalanced diabetes with HbA1c > 7. The difference between the total cholesterol, ASL and ASP parameters of the two populations was not significant. The study of correlation showed that the consumption of plant had an effect on the type of correlation between biochemical parameters of diabetic patients. Conclusions The consumption of medicinal plants did not affect the values of the measured biochemical parameters, while the correlation between these parameters can be modified.

The phenolic compounds in solvent extracts of Genista saharae were analyzed by Reversed-phase high-pressure liquid chromatography equipped with photodiode array detector (RP-HPLC-PDA) technique and evaluated for their antioxidant and antibacterial activities. The antioxidant activities were evaluated using hydrogen atoms transfer methods (DPPH, total antioxidant capacity, and reducing power assays) and single electron transfer (ABTS and cupric reducing antioxidant capacity assays). The antibacterial activity of extracts was tested against different strains using the minimal inhibitory concentration (MIC). Four phenolic acids (gallic acid, caffeic acid, p-coumaric acid, and sinapic acid), one flavonoid (quercetin), and one flavanone (naringenin) were identified with RP-HPLC. The chloroform extract exhibited antioxidant potential (IC₅₀ = IC₅₀ = 4.03 ± 0.0200 and 35.63 ± 1.42 µg L⁻¹) and antibacterial activity against the bacterial stains with MICs of 20 µg mL⁻¹. These results suggested a high contribution of quercetin and naringenin in the antimicrobial and antioxidant activities assessed.

Les substances naturelles issues des végétaux présentent des intérêts multiples mis à profit dans la biotechnologie tant dans l’industrie alimentaire, cosmétique que pharmaceutique. Parmi ces composés on retrouve une grande partie des métabolites secondaires qui se sont illustrés dans beaucoup de domaines et même en thérapie. Dans ce travail, nous avons étudié les effets antimicrobiens de Berberis vulgaris, une plante utilisée en Algérie et en particulier dans la région de Tlemcen. L’étude phytochimique qualitative réalisée sur les écorces de racine de Berberis vulgaris a montré la présence des alcaloïdes, des tanins, des stérols, des triterpènes et des composés réducteurs en grandes quantités, elle a aussi révélé des quantités inférieures des coumarines, des terpènes, des saponines et de mucilage. La détection de ces classes chimiques est suivie de la préparation des extraits en utilisant des solvants à polarité croissante et l’extraction des alcaloïdes totaux. Ensuite, les différents extraits ont été testés pour leur activité antimicrobienne sur différentes souches de bactéries et de levures de référence, en utilisant la technique de diffusion en milieu gélosé et la détermination des concentrations minimales inhibitrices (CMI). L’extrait méthanolique macéré a montré la meilleure activité antibactérienne avec des diamètres d’inhibition de 12,5 à 21 mm pour certaines souches. Aussi, les extraits de Berberis vulgaris et plus particulièrement les alcaloïdes ont montré une activité antifongique élevée sur les souches de Candida albicans (diamètres d’inhibition de 19 à 29 mm). Natural substances from plants have multiple interests exploited in the biotechnology industries both in food, cosmetic and pharmaceutical. These compounds include a large proportion of secondary metabolites which are illustrated in many areas and even in therapy. We investigated the antimicrobial effects of Berberis vulgaris, a plant used in Algeria, and particularly in Tlemcen region. The qualitative phytochemical examination performed on Berberis vulgaris root bark showed the presence of alkaloids, tannins, sterols, triterpenes and reducing compounds in large quantities, and it also revealed lower amounts of coumarins, terpenoids, saponins and mucilage. The detection of these chemical classes is followed by extraction using solvents with increasing polarity and extraction of total alkaloids. Then, the different extracts were tested for their antimicrobial potency on different reference strains of bacteria and yeasts, using the agar diffusion technique and the determination of minimum inhibitory concentration MIC. The methanolic macerated extract had the best antibacterial activity with inhibition diameters from 12.5 to 21 mm for some strains. Also, extracts of Berberis vulgaris and more specifically alkaloids showed a strong antifungal activity on Candida albicans yeasts (diameters inhibition 19 to 29 mm).

Lawsonia inermis Linn. (Lythraceae) or henna has been used since the earliest times as a medicine, preservative, and cosmetic. It has long been recommended in traditional medicine as an astringent, purgative, and abortifacient. Lawsone and six extracts of L. inermis plant, used by Algerian traditional healers to treat infectious diseases, were screened for their antifungal activity against filamentous fungi. Water and five organic extracts - DMSO, ethanol, chloroform, ethyl acetate, and di-ethyl ether - of L. inermis leaves, collected in the area of Adrar (Algeria), were prepared by soaking 25 g of powdered plant in 100 mL of solvent. The extracts were screened for antifungal activity using the poisoned food technique against five filamentous fungi. Results demonstrated that the best yield (8.03%) was obtained with the ethanol extract. The commercial lawsone showed potentially interesting MICs against the strains Fusarium oxysporum (12 µg/mL) and Aspergillus flavus (50 µg/mL). The ethanol extract showed the only interesting MIC (230 µg/mL of crude extract) against the strain F. oxysporum compared with other extracts. These results suggest that the Algerian L. inermis plant has antifungal activity that can be related to the presence of lawsone in the leaves plant. The results can be exploited largely in research of new antifungal drugs.

A series of new 2-(3-hydroxy-4-oxo-4H-naphthalen-1-ylidene) acetonitriles was prepared by the cascade Michael addition-elimination reaction of sodium 1,2-naphthoquinone-4-sulfonate with various substituted acetonitriles compounds in ethanol-water in presence of basic catalyst.