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This study aims to contribute to the valorizing of aromatic and medicinal plants of Morocco by studying the antioxidant and antifungal properties of the essential oils (EOs) of Allium sativum (AS) (garlic) and Urginea maritima (Syn. Drimia maritima) tested in vitro. After the hydrodistillation of EOs, we determined their physicochemical indices according to an international standard (Moroccan ISO standard), and the chemical composition of the oils was studied by gas chromatography coupled with mass spectrometry (GC-MS). Then, the antioxidant properties were determined using the free radical scavenging capacity of 2,2-diphenyl-1-picrylhydrazyl and the ferric-reducing antioxidant power of these oils. The evaluation of the antifungal activity was carried out by the direct contact method against two fungal strains, Fusarium oxysporum and Fusarium equiseti. GC-MS analysis revealed a significant percentage of terpenes in U. maritima EO, with terpinolene (21.82%) and estragole (6.24%) as the main compounds. Biological tests have demonstrated the remarkable antioxidant activities of this EO compared with AS EO, with an IC50 of 1.03 mg/mL and an RP0.5 of 1.60 mg/mL. On the other hand, while A. sativum (garlic) EO showed exceptional antifungal activities, with 100% inhibition and MICs of 0.5 µL/mL for F. equiseti and 2.5 µL/mL for F. oxysporum. Also, regardless of its antioxidant properties being moderate, this EO stands out for its efficacy against fungal infections of the Fusarium genus. In summary, the results suggest that U. maritima EO could be used as a natural source of antioxidants, while garlic EO could be considered a potentially effective treatment against fungal infections caused by Fusarium fungi.

This study investigates the green corrosion inhibition of mild steel in 1.0 M HCl using Myrtus communis essential oil (EOMC). Experimental and computational methods were combined to evaluate the corrosion inhibition effectiveness of EOMC. Weight loss measurements and electrochemical techniques, demonstrated that EOMC achieves a maximum corrosion inhibition efficiency of 94.81% at a concentration of 400 ppm of MCEO extract. The icorr significantly decreased from 983 µA/cm2 in the 1.0 M HCl solution to 51 µA/cm2 at 10−3 M, demonstrating the inhibitor's effectiveness. Polarization studies suggested mixed‐type inhibition, affecting both anodic and cathodic reactions, supported by changes in Tafel slopes. The Rct reached 462 Ω cm2 at 400 ppm of EOMC, enhancing the steel's protective capability. Higher temperatures increased the corrosion rate, with icorr values rising from 51 µA/cm2 at 298 K to 501 µA/cm2. Surface analysis using scanning electron microscopy coupled with energy‐dispersive X‐ray spectroscopy (SEM‐EDX) confirmed the formation of a protective layer on the steel surface in the presence of EOMC. Additionally, density functional theory (DFT) calculations and molecular dynamics (MD) simulations provided further insights into the adsorption behavior of the EOMC molecules on the MS surface, revealing that the inhibition process involves both physisorption and chemisorption mechanisms. [ABSTRACT FROM AUTHOR]

The purpose of this study is to examine the adsorption process of a cationic dye, in this case Methylene Blue (MB), on Moroccan natural clay collected from Marrakech region. The influence of physicochemical parameters (contact time, pH, mass of the adsorbent, initial Methylene Blue concentration and temperature) on MB adsorption performance on clay was studied. Experimental results showed a remarkable and rapid elimination within the first twenty minutes of contact of the two phases. The adsorption kinetics of Methylene Blue was evaluated applying pseudo first and second order kinetic models. The kinetic study demonstrates that adsorption obeys the pseudo second order model. The adsorption process was determined by applying the Langmuir and Freundlich isotherms. The maximum adsorption capacity of the raw clay is about 32 mg g-1. The temperature effect on dye adsorption was also examined and thermodynamic parameters were calculated. [ABSTRACT FROM AUTHOR]

The cationic exchange resin Amberlite®IRC-50 was evaluated as a potential adsorbent for toxic methyl orange (MO) dye. The adsorption study was evaluated as a function of time, temperature, pH value, optimal concentration of the anionic dye MO and adsorbent the cationic resin. The maximum retained content of MO was 68.2 mg g–1 of concentration 200 mg L–1. The various values of the rate constant for adsorption process of the dye MO were determined. Kinetic analysis of the adsorption study of the impact of the concentration was compatible with linear pseudo-secondorder (The experimental capacity is very close as the capacity calculates, 68.2 mg g–1 of experimental capacity and 76.9 mg g–1 of capacity calculates). The thermodynamic parameters ΔG° (–1.84 at –4.00 kJ mol–1), ΔH° (19.62 kJ mol–1) and ΔS° (72.00 kJ mol–1) were determined using the Van’t Hoff equation. The values of these parameters indicate that the adsorption process is an endothermic and spontaneous. The adsorption process fit well with the Langmuir adsorption isotherm model. [ABSTRACT FROM AUTHOR]

Summary: During this present study, we tested the adsorption performance of heavy metal ions; bivalent lead (Pb (II)) and the anionic dye (methyl orange (MO)) from model aqueous solutions with the ion exchange resin of the Amberlite®IRC-50 type. This performance was evaluated using inductively coupled plasma (ICP) and atomic absorption spectroscopy (AAS). The pH of the solution was adjusted to 6.5 for the bath temperature, the initial mass concentration of Pb (II) and MO was adopted at 20 mg/L, the mass of the resin-type adsorbent Amberlite®IRC-50 was taken at 0.1g and the adsorption capacity Qe was studied. The results obtained during this study show that the kinetic study of the adsorption was obtained at the contact time t = 30 min for the metal Pb (II) and at t = 60 min for the dye MO. These results also showed that the equilibrium of adsorption was reached at time t = 60 min with an adsorption performance of around 99% for Pb (II) and around 96% for MO. Note that the parameters of different mathematical models i ndicate that the adsorption process is spontaneous in the second degree. [ABSTRACT FROM AUTHOR]