Quality criteria, chemical composition and antimicrobial activity of the essential oil of Mentha suaveolens Ehrh.

The aim of the present study is the valorization of the essential oil of Mentha suaveolens Ehrh. The research plan and methods included 3-axis: the first axis consists of studying the organoleptic and physicochemical characterization of the essential oil, the second is the chemical analysis carried out by Gas Chromatography/Mass Spectrometry (GC/MS) and the third consists of evaluating its antimicrobial activity against selected microorganisms. The results obtained for the organoleptic and physicochemical properties are as follows: appearance: Liquid, mobile and clear, odor: Strong odor characteristic of Mentha suaveolens Ehrh, color: Pale yellow; relative density (0.92), miscibility with ethanol (1V/2V), freezing point (Tfreezing < -10 °C), refractive index (1.5256), rotating power (+0.825), acid index (1.68), ester index (68.44), saponification index (70.13) and iodine index (12.05).Chemical analysis identified 69 compounds which are mostly oxygenated monoterpenes such as piperitenone oxide (32.55%), pulegone (10.14%), piperitone oxide (8.34%), etc. The microbiological tests were carried out by an agar diffusion test using the essential oil of Mentha suaveolens Ehrh. The microbiological tests were carried out by a diffusion test on agar, these tests are carried out on six microbial strains (five bacteria and one yeast).The inhibitory effect of our oil is well marked against bacteria: Proteus mirabilis (17.50 ± 0.70 mm at 50 µL/mL), Enterococcus faecalis (17.00 ± 1.00 mm at 50 µL/mL) and Staphylococcus coagulase negative (16.33 ± 0.57 mm at 50 µL/mL) while it was moderate against Escherichia coli (14.33 ± 1.15 mm at 50 µL/mL) and Streptococcus spp (13.00 ± 0.00 mm at 50 µL/mL) as well as against yeast, Candida albicans (15.33 ± 1.52 mm at 50 µL/mL). It appears from these results that our oil is of high quality and can be used in several areas. The results obtained are therefore promising and thus open the way for manufacturers to use this essential oil of Mentha suaveolens Ehrh in the pharmaceutical, cosmetic, agricultural and food industries.

Chemical Composition and Antioxidant Capacity of Lepidium sativum Seeds from Four Regions of Morocco.

Lepidium sativum seeds (LSS) from four regions of Morocco have been analyzed for their total chemical composition and antioxidant activities. In the seeds of this plant, the moisture content and yield were, respectively, 9.24-9.88% and 19.13-19.94% of dry weight. Chemical analysis of the seeds revealed amounts of fatty acids, sterols, and tocopherols. The most important fatty acids are linolenic acid (33%) and oleic acid (23%). The main sterol is ß-sitosterol (50%); the vegetable oil of Lepidium sativum revealed an amount of tocopherol (∼1500-1900 mg/kg) with dominance of γ-tocopherol. The Folin-Ciocalteu trial evaluated the total phenolic compound, DPPH radical scavenging, ABTS, and chelated iron ions. FRAP measured antioxidant potency. Results indicated that methanol extract from Lepidium sativum was a more potent reducing agent and radical scavenger than ethanol extract. Changes in the total phenolic content and antioxidant capacity of Lepidium sativum in four different regions grown under normal conditions were evaluated. The antioxidant activity of different extracts was found to correlate significantly with their total phenolic content. These results suggest that Lepidium sativum seeds could be used in food supplement preparations or as a food additive, for caloric gain or for protecting against oxidation in nutrient products.