Context: Infectious diseases are the cause of death worldwide. As antibiotic resistance is rising, researchers are looking for new therapies. The Gram-negative bacterium Escherichia coli, causes acquired hospital infections and results in intestinal infections and many infections out of the intestine, like urinary tract infections (UTI), cholecystitis, wound infections, meningitis, septicemia, pulmonary infections, etc. Plants are a good source of bioactive compounds; hence, they can be effective in treating several illnesses. The purpose of this research was to peruse the antibacterial activity of various herbal extracts on E. coli. Evidence Acquisition: This research was obtained from various articles published from 2000 to 2017 from the PubMed, ScienceDirect, Springer, Islamic Science Citation, and Magiran databases. The keywords used were E. coli, herbs, natural antibiotics, and antimicrobial activity. Results: The results showed that the ethanolic extracts of medicinal plants showed better inhibitory function against E. coli than other solvents. Conclusions: The obtained results showed that medicinal herbs can be considered as the main medicinal agents capable of affecting infections caused by E. coli.

Objectives Although dental caries is the most common chronic oral disease globally, there is no comprehensive plan for preventing this microbial disease. Streptococcus mutans is one of the essential causes of dental caries. Owing to the adverse effects associated with antibiotics, researchers are focusing their efforts on the development of antimicrobial compounds derived from medicinal plants. This study aimed to investigate the antimicrobial effects of the ethanol extract derived from the leaves of Myrtus communis on S. mutans. Methods In this in vitro study, the researchers initially procured the Myrtus communis extract. Subsequently, they determined its dry weight and evaluated its antimicrobial activity utilizing the well-dilution method. The antimicrobial efficacy was determined by measuring the minimum inhibitory concentration (MIC), minimum bactericidal concentration (MBC), and the inhibition zone diameter surrounding the extract. Ultimately, the data were examined using the Mann-Whitney test. Differences less than (P<0. 05) was significant statistically. Results The MIC and MBC of the extract for S. mutans were found to be 5 mg/mL and 10 mg/mL, respectively. Chlorhexidine, used as a positive control, exhibited the same values. Furthermore, the diameter of the inhibition zone around both the extract and chlorhexidine was measured to be 17±1 mm and 15±1 mm, respectively. The difference between these measurements was not statistically significant (P=0. 077). Conclusion The ethanol extract from the myrtle leaves was as efficient as chlorhexidine mouthwash against S. mutans. Further investigations are needed into the antibacterial effects of different medicinal plants on cariogenic microorganisms.