Eryngium bourgatii Extract Inhibits Iron Corrosion and Bacterial Growth in Fresh and Marine Water Media

Abstract

Abstract Bi-functional effect of Eryngium bourgatii extract on inhibiting iron corrosion and bacterial growth in both fresh and marine water media was studied using weight loss measurements for corrosion inhibition and well diffusion method for bacterial growth inhibition. At 150 mg/100 mL inhibition efficiency of corrosion reached 95% and 91% in fresh and marine medium respectively. The results showed clearly that E. bourgatii ethanol-hexane crude extract is strongly active in both media. Three quantitative methods were applied for measuring corrosion rate of iron metal cylinders: relative weight loss, iron released in the medium, and turbidity. Statistical analyses showed that the three methods are comparable and any method of the three could be used to measure corrosion rate. Experimental data obeyed Langmuir isotherm model. Optical and scanning electron microscopy (SEM) images revealed the smoothness and homogeneity of adsorption layer on the iron nail surface. Regarding bacterial growth inhibition at ratio of 150 mg/100 mL medium was found to be effective.