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The present work was aimed to study the toxicity of the essential oils of three aromatic and medicinal plants on the tomato leaf miner Tuta absoluta and the Medfly Ceratitis capitata as an alternative to conventional pesticides. We carried out a phytochemical and insecticide study of T. zygis L., S. officinalis L. and M. suaveolens Ehrh. essential oils (EOs) through the study of their chemical composition and their toxicity on C. capitata adults and T. absoluta larvae. The extraction of the EOs by hydrodistillation showed yields of 3.87 ± 0.03, 4.09 ± 0.23 and 4.35 ± 0.11 for T. zygis, S. officinalis L. and M. suaveolens Ehrh., respectively. The identification of the chemical composition of the EOs by GC/MS showed that oxygenated monoterpenes constituted the most abundant group for all the extracted EOs. The major compounds were rather diversified depending on plant species. In fact, the S. officinalis L. EO mainly contained trans-thujone (21.80 %), the M. suaveolens Ehrh. EO mainly contained piperitenone oxide (71.19%), and carvacrol (61.60%) was the main component of the T. zygis L. EO. An insecticidal effect was observed for the three studied EOs on C. capitata adults and T. absoluta larvae. The observed LD50 values were 0.80 µL/mL and 11.04 µL/mL for M. suaveolens and S. officinalis, respectively, on T. absoluta larvae. For C. capitata adults, the obtained LD50 values were 0.9 µL/mL and 11.78 µL/mL for M. suaveolens and T. zygis, respectively. The presented findings could contribute to the development of biopesticides for plants as a component of integrated pest management strategies in citrus and tomato crops.

To research natural antioxidants, the present study aims to extract and identify new substances of natural origin through the phytochemical study and the evaluation of the antioxidant activity of extracts of twigs and leaves of Tetraclinis articulata (Vahl) Masters, harvested from the Khenifra region (Middle Atlas, Morocco). The Phytochemical screening, based on precipitation and complexation reactions, showed that the twigs and leaves of T. articulata contain flavonoids, tannins, alkaloids, mucilages, sterols and triterpenes. The extraction of the phenolic compounds was done using a Soxhlet apparatus. The assays of polyphenols, flavonoids and condensed tannins of the obtained extracts showed that the highest content of polyphenols was recorded by the ethyl acetate extract (654.69 ± 0.33mgEAG/gE). Concerning the flavonoids, the hydroethanolic extract records the highest content (20,31 ± 0,02mgEQ/gE). For the condensed tannins, the highest content was observed by the extract of the residual phase (27.72 ± 0.11mgEC/gE). Indeed, due to the analysis by HPLC/SM, we were able to identify in the E.MeOH of T. articulata seven flavonic glycosides which are Catechin, B-type (Epi) catechin dimer, gallocatechin, Myricetin-hexose, Myrcetin-rhamnose, Quercetin-3-o-Rhamnoside and kampferol-deoxyhexose. The in vitro evaluation of the antioxidant activity of T. articulata extracts was performed by DPPH and FRAP methods. The extracts of T. Articulata showed a significant antioxidant power. The lowest IC50 and EC0.5 were recorded by E. EtOH. These low concentrations (IC50 and CE0.5) obtained by DPPH and FRAP are 70 ± 0.07 µg/ml and 104.12 ± 1.02 µg/ml, respectively. This study revealed that the extracts of T. articulata are potentially important due to their richness in secondary metabolites of its antioxidant power.

Mentha suaveolens Ehrh is a plant that belongs to the lamiaceae family. It is widely used in traditional medicine because of its various therapeutic properties. The main objective of this study is ...

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...

Plants of the Lamiaceae family are widely used for medicinal, cosmetic and culinary purposes. Phenolic compounds such as flavonoids and tannins are the main constituents of these plants; they have a proven multidirectional biological activity. Polyphenols have exceptional antioxidant potential, and they can intervene in the prevention of many health disorders. This work aims to study the composition and antioxidant power of phenolic compounds from crude extracts and fractions of Origanum elongatum leaves. This specie was subjected to phytochemical study through precipitation, turbidity and coloring reactions to highlight their secondary metabolites qualitative composition. Polyphenolic extraction was made by Soxhlet using two solvents: methanol 70%, ethanol 70%. Then, methanol’s crude was fractionated with solvents having escalating polarity; ethyl acetate, n-butanol. The polyphenols and flavonoids contents were spectrophotometrically estimated using Folin-Ciocalteau and Aluminum Trichloride methods. The antioxidant power of crude and fractionated extracts was evaluated by diphenyl-picryl-hydrazyl (DPPH●) and iron (FRAP) tests. The screening tests showed the existence of polyphenols, mucilages, sterols and triterpenes, oses and holosides. The highest yield of extraction is obtained by 70% methanol, with an average of 32.29%. Quantitative assays indicated that the hydroethanolic extract and the ethyl acetate fraction possessed high amount of polyphenols and flavonoids compared with other fractions and subsequently exhibited a marked scavenging activity on DPPH radical (IC50 = 0,085±0,002 and 0,112±0,003 mg/ml, respectively) and high reductive ability on ferric ion assay with IC50 = 0,181±0,004 mg/ml, 0,291±0,005 mg/ml, respectively.

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 objective of this study was to identify new bioactive substances through the phytochemical study and evaluation of the antibacterial activity of the essential oils of Tetraclinis articulata (Vahl). Harvested in April 2016, in the region of Khenifra (Middle Atlas-Morocco).   Separate of hydrodistillation extracts of the three organs (branches, leaves and fruits) of Tetraclinis articulate were performed. The yields of essential oils are 0.92% for fruits; 0.41% for branches and 0.61% for leaves.   The GC/MS analysis allowed the identification of 33 compounds in essential oil leaves, 20 compounds in excess fruits and 58 compounds in branches. The main compounds are bornyl acetate (38.54%) and α-pinene (6.71%) for leaves. α-pinene (22.12%); 13-epi-mannol (3.58%) and retinol (3.44%) for branches. Bornyl acetate (19.96%); α-pinene (12.47%) and retinol (11.98%) for fruits.   The antibacterial properties of the essential oil of leaves of Tetraclinis articulata (Vahl) were tested in clinical bacterial strain. The essential oils inhibit the growth of Escherichia coli, Staphylococcus aureus and Klebsiella pneumoniae at 1.2 µl/ml; 2.4 µl/ml and 9.7 µl/ml respectively.   Indeed, the resistance of bacteria to antibiotics is known for its adverse effects on human

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).