Investigating the Antimicrobial Activity of Different Extracts of Echium on Selected Gram-Positive and Gram-Negative Bacteria

Abstract

Introduction: Medicinal plants have had a special value and importance in providing health and wellness of communities both in terms of treatment and prevention of diseases. The aim of this research was to investigate the antimicrobial activity of different extracts (aqueous, ethanolic, and methanolic) of two types of Echium (Helioteropium ellipticum and Anchusa strigosa) on Staphylococcus aureus, Bacillus Cereus, Escherichia Coli, Salmonella Typhi and Shigella dysentery bacteria. Material and Methods: Extracts were prepared by soaking method. Antimicrobial activity was determined by two methods: dilution sequence in liquid medium and diffusion from disk in solid medium. The data were analyzed with SPSS24 software. Results: Gram-positive bacteria showed more sensitivity to the extracts than Gram-negative bacteria. Antimicrobial activity of Heliotropium ellipticum was more than Anchusa strigosa. Aqueous extract has the lowest and ethanolic extract has the highest antimicrobial activity. Staphylococcus aureus showed the highest and Escherichia coli the lowest sensitivity to the extracts. Staphylococcus aureus bacteria showed the largest diameter of non-growth aura (20.67 mm) at the concentration of 50 mg/ml of ethanolic extract, and the MIC of Staphylococcus aureus had the highest sensitivity at 312.5 PPM dilution. Conclusion: The two tested species have good antimicrobial activity and they can be used as natural substitutes for chemical antimicrobial agents.