Ziziphus Spina Christi Leaves Methanol Extract Evaluation as Antifungal, Antibacterial, Antioxidant and Green Inhibitor for Carbon Steel Alloy Corrosion in Hydrochloric Acid

Abstract

In this study, Zs-c leaves were extracted by a 70% CH3OH solvent. The extract was investigated as green corrosion inhibitor for CS C1010 alloy in 0.1 M HCl. The study was done with different inhibitor concentrations (1, 2, 8 and 9 ppm). The extract showed the highest IE of 96.06%, at 9 ppm. The inhibitor adsorption on the CS alloy surface was found to obey the Langmuir's adsorption isotherm model. Kads, ΔHads, ΔSads and ΔGads were also calculated. The temperature effect on Zs-c leaves extract IE%, with the optimal concentration of 9 ppm, was studied at 35,45 and 55 ºC. The results showed that IE% decreased with raising solution temperatures. In addition, 𝐸 * , ΔH, ΔS and ΔG kinetic parameters were calculated. On the other hand, phytochemical tests and quantitative analysis, such as TPC and TFC, were also carried out. In addition, the anti-bacterial activity or growth inhibition of bacterial strains, such as Ec and Sa, were studied. Antifungal activity or growth inhibition studies of Ca and An species were also carried out, at a 100 mg/mL concentration. Anti-oxidant activity was also investigated by DPPH, at concentrations of 100, 250, 500, 750 and 1000 µg/mL, and good results were obtained.