Search

Hydrosols (HYDs) have attracted a great interest this last decade by the scientific community. Although, studies about HYDs remain limited compared to those dealt with essential oils (EOs). These magic waters have found a huge interest in the cosmetic, food and phytotherapeutic industries. Their biological activities have not yet been assessed. The aim of this present work was to evaluate the antibacterial activity of three HYDs and to compare this activity to that of EOs from Mentha species facing some bacteria strains that caused various human diseases and infections. M. pulegium, M. suaveolens and M. spicata were collected from Azrou (Moroccan Middle-Atlas). Their EOs and HYDs were tested on six bacteria strains: S. aureus, E. coli BLSE, E. coli (wild-type), Ps. aeruginosa, Ps. putida, and P. mirabilis, using the micro-dilution and agar diffusion methods. The chemical compositions of three HYDs were different from the EOs; they were rich in hydrophilic and oxygenated compounds and lack in hydrocarbon constituents. The qualitative evaluation of the antimicrobial activity showed strong power for all the tested EOs by highlighting zones of inhibition with diameters exceeding 20 mm, thus showing significant sensitivity of the treated bacteria. These results were confirmed by quantifying this activity by MIC and MBC values, thus demonstrating their antibacterial power. As for HYDs, they have also shown their inhibitory efficacy against certain strains. Consequently, these promising results could serve as a basis to confirm the efficacy of these natural products and their ability to serve as alternative antimicrobial agents. Keywords: Mentha, Essential oil, Hydrosol, Bacteria, Antibacterial activity.

Silver nanoparticles AgNPs were synthesized from an extract of Pistacia atlantica plant. After mixing the silver nitrate solution and extract of P. atlantica leaves, they changed its color to dark brown. UV–vis spectroscopy result showed maximum adsorption at 468 nm, which represents the characteristic surface plasmon resonance of nanosilver. FTIR spectroscopy results recorded a downward shift of absorption bands between 500 and 1700 cm−1 indicting the formation of silver nanoparticles. X-ray crystal analysis showed that the silver nanoparticles are highly crystalline and exhibit a cubic, face-centered lattice with characteristic (111), (200), (220), and (311) orientations. Composition analysis obtained from SEM–EDXA confirmed the presence of elemental signature of silver. Results also showed that biosynthesized AgNPs exhibit remarkable antioxidant activity using DPPH method with IC50 = 0.47 mg/ml. In addition, synthesized AgNPs were also found to control the growth of E. coli, S. aureus and Acinetobacter baumnnii on nutrient medium with 13, 12 and 11 mm mm zone of inhibition, respectively. The main compounds that were identified in the methanolic and the ethanolic extracts of P. atlantica Desf are ascorbic acid, gallic acid, tannic acid, rutin, and quercetin which were performed by HPLC technique. The AgNPs synthesized from the leaf extract of P. atlantica can be a good method for the preparation of various nano formulations.

The present study aims to determine the chemical composition of Pistaca atlantica Desf. collected in the Khenifra region (Morocco). Compounds chemicals of the essential oil were analyzed by gas chr...

The Atlas Pistachio, Pistacia atlantica Desf., from the family of Anacardiaceae is a widespread species in Morocco and widely present in traditional pharmacopoeia 1. This species is frequently infected by Forda riccobonii and Geoica swirskii that are foliar galls-inducing aphids.The aim of this study was to compare the chemical composition of essential oils (EO) of the infected and healthy leaves of Pistacia atlantica. The extraction of essential oils was performed by hydro-distillation using Clevenger, phytochemical screening was realized by revelations tests and chemical composition was identified by gas chromatography coupled with mass spectrometry (GC-MS).Phytochemical analysis showed the presence of some biologically active chemical compounds such as tannins, flavonoids, sterols and triterpenes. The infected leaves were richer in tannins than healthy ones, especially in gallic tannins.Also, the results reaveled that the EO yield of leaves with galls was higher (0.71%) than that of healthy ones (0.11%); also, the first type of leaves was predominated by α-Pinene (19.76%) followed by Terpinen-4-ol, Spathulenol and Sabinene with percentages of 11.94%, 8.90% and 7.63%, respectively. Whereas, healthy leaves were predominated by α-Amorphene (15.05%) followed by Terpinen-4-ol, Spathulenol and α-Muurolene with percentages of 7.17%, 6.46% and 6.20%, respectively.So, we arrived to conclude that infected leaves have a higher level of monoterpenes hydrocarbon than healthy ones that contains interesting molecules useful in differentes domains, especially in the health field.

The present study aims to determine the chemical composition of Salvia officinalis L., collected in Khenifra region (Morocco), have a phytochemical screening and to evaluate its antioxidant activity, as well as its corrosion inhibiting powers using two methods: the potentiodynamic polarization and impedance spectroscopy (EIS) measurements.The phytochemical screening helped us to highlight the presence of polyphenols, catechics and Gallic tannins, flavonoids, saponins and Terpenoids. It showed that the methanolic extract was very rich in total phenols (1.044 ± 0.004 mg GAE/g of extract) and flavonoids (0.037 ± 0.003 mg EQ/g of extract). Leaves of Salvia officinalis L. were steam distilled using a Clevenger apparatus. The yield of essential oil was 4.13 ± 0.01%, and its analysis by GC–MS has identified 105 components with the dominance of Trans-Thujone (17.74%), 1,8-cineol (12.63%), Camphor (12.24%), Caryophyllene (9.87%), α-pinene (7.82%), Dehydra-Aromadendrane (7.29%), and Guaiol (7.03%). The results of antioxidant activity allowed the determination of IC50 (IC50 = 309.42 mg/ml) for the oil. The latter has shown an inhibition efficiency of 83.06% and 70.58% for the both methods respectively at a concentration of 4 g/l, the methanolic extract which has shown an inhibition efficiency of 91.62% and 49.70% respectively at the same concentration. Keywords: Salvia officinalis L., HE, Polyphenols, GC–MS, Antioxidant activity, Iron corrosion inhibition

Spearmint (Mentha spicata L.) is one of the most used species in Morocco. The whole herb and essential oil are used in flavoring tea and also have medicinal, cosmetic and industrial importa...

This work consists of the comparison of the chemical composition, the antioxidant activity, and the antimicrobial effect of two species of the genus Lavandula essential oils (EOs) and extracts (hydroethanolic, aqueous and decocted), that were collected from the region of Ifrane in Morocco "Lavandula angustifolia and Lavandula peduncultata". Gas chromatographic analyzes coupled with mass spectrometry of the studied EOs showed that L. angustifolia contains camphor and linalool as majority compounds with 20,17% and 12,41% respectively, while camphor (41,15%) and fenchone (15,70%) are the major compounds of L. peduncultata. The dosage of hydroethanolic, aqueous and decocted extracts showed that the content of polyphenols and flavonoids is higher in the hydroethanolic extracts of L. pedunculata, while L. angustifolia contains the highest content of tannins. The determination of the antioxidant activity was carried out using FRAP and DPPH methods, the last method revealed that the EO of L.angustifolia is less effective (IC50=7,98 mg/ml) than that of L. pedunculata (EC50=7,47 mg/ml) while, there was no great divergence concerning the IC50 values of the hydroethanolic and decocted extracts of the two species. As for the aqueous extract, the value recorded by L. pedunculata was slightly higher than that of L. angustifolia. Finally, tests of the antimicrobial activity of EOs and extracts of the two species were carried out on six bacteria and five fungal strains whose antimicrobial power was remarkable. As a conclusion, the two Lavenders’extracts can be considered as alternative sources of powerful natural antioxidants, antifungals and antibiotics.

The correlation between the contents of polyphenols and flavonoids and the degree of antioxidant activity of various extracts from M. pulegium (L.) and M. spicata (L.), obtained by different solvents and methods, was investigated. The crude extracts were prepared by mixing areal parts in powder with methanol/water solution. They were subjected later to liquid-liquid extraction via solvents with progressive polarity (chloroform, ethyl acetate and n-butanol) by maceration and soxhlet techniques. The total phenol and flavonoids contents from crude extracts and their fractions were determined by using Folin-Ciocalteu and AlCl3 assays respectively. The antioxidant activity of extracts was evaluated by DPPH• (1,1-Diphenyl-2-picrylhydrazyl) radical scavenging test. This activity was measured by inhibition concentration 50% (IC50) values. Generally, higher extract yields were obtained by the soxhlet extraction technique; the crude extracts recorded the best yields for M. pulegium by soxhlet (26.37%) and maceration (13%) while for M. spicata, the aqueous extract by soxhlet (34.9%) and crude one by maceration (9.4%) showed the higher yields. The higher phenolic and flavonoids contents were found in crude extracts by maceration for both mints whereas by soxhlet, the ethyl acetate and/or n-butanol extracts demonstrated the strongest contents. These extracts, rich in flavonoids, showed a positive correlation since they have exhibited better antioxidant activity compared to ascorbic acid as the antioxidant reference (IC50= 0.051 mg/ml).

The main objective of this work is to establish a first state of the situation of the groundwater quality in the region of El Hajeb (Morocco) which houses the wild municipal landfill. Within the framework of a first sampling campaign, groundwater samples were then collected from 43 groundwater points during the May 2015 until January 2017. Analyses using standardized methods were based on physicochemical parameters such as pH, electrical conductivity, iodide, dissolved oxygen, oxidizability to permanganate…. The results highlighted the existence of organic pollution, due to the presence of the wild discharge, septic tanks and pit latrines revealed by the concentration in oxidizability to KMnO4, which exceeded the Moroccan standards set at 5 mg/L. Pollution by Chlorides in some areas of the aquifer was also revealed, with high chloride levels exceeding 380 mg/L and was confirmed by high conductivity values (3700 μS/cm). If a pollution of agricultural origin is evoked, one cannot neglect the effect of the practice of the time modification technique on the concentration of some major ions. These first observations, have allowed us to confirm the extent of leachate plume of the wild landfill to groundwater, so the decision-makers and the persons in charge are being solicited to intervene to protect the water table.

The dump in the town of El Hajeb (Morocco) is devoid of a collection and treatment system of the generated brownish effluents known as leachates. In a permeable soil and of a water table circulating in shallow depth, these percolate, after their generation, accumulate at the bottom of the waste and can infiltrate through the ground to reach the underlying water table, thus causing its contamination. Leachate would require, therefore, a specific treatment before their rejection in the receiving environment. This study aims to make a physicochemical characterization of these leachates. To do this, we conducted a series of sampling, from May 2015 to January 2017. During this period, the physicochemical analysis revealed, on the one hand, that it is discharge juice in the acidogenesis phase, conveying a significant pollutant load rich in organic and inorganic matter (COD = 23597.5 ± 595.61 mgO2 L-1), in mineral salts (EC = 17.55 ± 0.72 mS cm-1) and in nutrient salts (TKN = 888.54 ± 13.53 mg-N L-1 and TP = 139.65 ± 48.89 mg-P L-1), concentrations exceed the values allowed by Moroccan and international standards, what makes these effluents toxic to the surrounding environment. By the present study, we incite decision-makers to manage well effectively the discharges taking into account the risks of the leachates generated.

Semi-empirical methods AM1 and PM3 have been used to study the stereochemistry of the addition reaction of crotylmagnesium chloride on a series of cyclic and acyclic enones. The mechanism of this reaction has been studied by localizing the different possible transition states. The stereochemistry of the diastereoisomers obtained can be explained by comparison of the values of the energy of activation. We show in this paper that the major diastereoisomer for acyclic enones is formed via a boat-shaped transition state where the magnesium reacts with the trans conformation. Whereas for cyclic enones such as pulegone or methyl pulegone, a chair transition state where the magnesium adopts a cis conformation explains the final stereochemistry. Moreover, we demonstrate that the stereoselectivity depends of both steric and electronic factors.

Cycloaddition of nitrones 1 with methylene-gamma-butyrolactones 2, 3 and 4 afforded spiroadducts 5, 6 and 7 with high selectivity. Mixtures of diastereoisomers were usually obtained, whose structures were established by 1H and 13C NMR spectroscopies or X-ray crystallography. Treatment of spiroadducts in acidic and alkaline media led to different, unexpected and novel rearrangements.