Search

Asteriscus graveolens(Forssk.) Less. and Brocchia cinereaDelile. were investigated within the scope of discovering natural antioxidants, as they are endemic and rare, and there are few phytochemical studies on the two species. This study aims to evaluate organ-dependent variability in phytochemical content in different extracts from various organs of both species and evaluate their antioxidant activities by scavenging free radicals. The comparative study of the organ and extraction solvent-dependent variability in total phenolic, and flavonoid content, as well as correlations between phenolic content and antioxidant activity, was performed using principal component analysis and hierarchical agglomerative clustering. Interesting results were obtained from this study. In particular, quantitative analysis showed that Asteriscus graveolensleaves were very rich in phenolic compounds and exhibited higher antioxidant activities. Statistical analysis confirmed the correlation between total phenolic content, total flavonoids content, and antioxidant capacity. The results confirmed organ and extraction solvent-dependent variability. The results obtained from this research showed that the extracts of this species are rich in bioactive compounds and might be evaluated as a potent source of antioxidants. Due to their antioxidant capacity Asteriscus graveolensand Brocchia cinereaextracts can be used in the treatment of chronic diseases caused by oxidative stress.

The study of the inhibition of the ecological corrosion of steel in the 1M hydrochloric acid medium by aqueous and ethanolic extracts of Pelargonium graveolenswas carried out using gravimetric, electrochemical, high-performance liquid chromatography (HPLC), and scanning electron microscopy (SEM/EDX). The results of this study showed that inhibitory efficacy (IE) increases with increased concentration. It reaches a maximum value of 97% for the aqueous extract of P. graveolensand 92% for the ethanolic extraction for the concentrate of 1.0 g L−1and decreases with the increase in temperature. The study of the influence of temperature has made it possible to understand the mechanism of action of these inhibitors on the corrosion of the steel so that the active molecules of the studied extracts are fixed on the metallic surface by forming physical bonds according to the adsorption isotherm Langmuir. These extracts behave as mixed-type inhibitors. These results are confirmed by a study of density functional theory (DFT) using the B3LYP/6-31G(d,p).

The aim of the present study is the valorization of the plant Dysphania ambrosioides(L.) in the inhibition of corrosion. Analysis of the extract by gas chromatography revealed the dominance of ascaridole epoxide (16.53%), thymol (13.25%), and n-hexadecanoic acid (9.62%). In this research, the effect of the extract on corrosion inhibition of mild steel in 1.0 M HCl solution was analyzed using weight loss measurements, potentiodynamic, polarization (PP) and electrochemical impedance spectroscopy (EIS). From the generated results, the optimum value (E%) of Dysphania ambrosioidesleaf extract was recorded at 94%, 95%, and 93% at a concentration of 1.0 g/L according to weight loss methods, PP and EIS, respectively. Polarization curves indicated that the extract acted as a mixed-type inhibitor. Adsorption on the mild steel surface obeyed the Langmuir isotherm. The activation energy values ΔGads0(− 24.89 kJ.mol−1) confirmed a physical process of adsorption of this inhibitor. The study of adsorption kinetics showed a maximum inhibitory efficiency of 91.9% after 1 hour of immersion time. Scanning electron microscopy revealed the formation of a protective layer on the surface of the steel emerging in the inhibitor unlike that emerging in 1.0 M HCl which is heavily corroded. The structural and electronic properties of the main components of this extract were calculated using density functional theory (DFT) at B3LYP/6-31G (d, p), the results confirmed the high reactivity of the molecules of thymol and ascaridole epoxide to adsorb on the steel surface.

AbstractAqueous, organic extracts and essential oils of aerial parts of two chemotypes of Seriphidium herba-albawere investigated for their in vitroantimicrobial properties. The plant was collected from Errachidia and Oujda (Morocco). The antimicrobial activity was evaluated against thirteen microorganisms using the disc—diffusion assay, well in agar method, minimal inhibition concentration (MIC) and minimal bactericidal concentration (MBC) values. The different extracts tested had no antimicrobial effect against the test microorganisms whereas the essential oil had inhibitory effects on the growth of bacteria, yeasts and fungi. The combination of essential oils of S. herba-albaand Dysphania ambrosioidesexhibited synergic effect against Streptococcus agalactiae.

AbstractCrude, aqueous, ethanol extracts and essential oils of aerial parts of Dysphania ambrosioideswere investigated for their in vitroantimicrobial properties. The plant was collected from Agouray village near Meknès city of Morocco. D. ambrosioidesis widely used as traditional folk medicine in Morocco. The main components in the oil were?-terpinene (61.04%), 4-carene (13.55%) and p- cymene (12.94%). The antimicrobial activity was evaluated against 12 microorganisms using the disc—diffusion assay, well in agar method, minimal inhibition concentration (MIC) and minimal bactericidal concentration (MBC) values. The different extracts tested had no antimicrobial effect against the test microorganisms whereas the essential oil had inhibitory effects on the growth of bacteria, yeasts and fungi.

In the present work, the extraction and the variation of total phenolic and the flavonoid content of the Halimium halimifolium plant (the leaves and the stems) harvested from Morocco have been studied. It explores extracting the essential oil of this plant and analyzing its chemical composition by the gas chromatography-mass spectrometry (GC/MS). Interesting results have been obtained, in particular, the presence of 26 compounds where the major one is (+)-2-Bornanone (38.26%) followed by Eucalyptol (27.74%). This essential oil proves great antioxidant capacities which is measured with the total antioxidant activity (TAC) and the organic chemical compound 2,2-diphenyl-1-picrylhydrazyl (DPPH) assays. On the other hand, using solvents with different polarities (the hexane, the dichloromethane, the ethyl acetate, the ethanol, and the water), the quantifying of the total phenolic and the flavonoid content for different crude extracts of the Halimium halimifolium was done. The results show simultaneous increasing in the total phenolic content of the crude extract and the solvent polarity.