An experimental assessment of several medicinal plant extracts' antibacterial activity against harmful microorganisms

Author(s): Shaymaa Hamood Karakosh
Date: 09/10/2026
doi: https://doi.org/10.5281/zenodo.8425890

---

Abstract

The hunt for substitute antimicrobial agents made from natural items  has been brought on by the 
emergence of antibiotic-resistant bacterial species. The present experimental laboratory study was 
designed to investigate the role of the extracts of ethanol, garlic (Allium sativum), turmeric (Curcuma 
longa), ginger (Zingiber officinale), oregano (Origanum vulgare) and neem (Azadirachta indica) against 
some harmful microorganisms such as Salmonella typhi, Pseudomonas aeruginosa, Escherichia coli and 
Staphylococcus aureus.   Disc diffusion was used to assess plant extracts that were made by ethanol 
extraction. procedures,  agar well diffusion, minimum inhibitory concentration (MIC), and minimum 
bactericidal concentration (MBC). Garlic extract exhibited inhibition zones ranging from 21-29 mm and 
oregano extract exhibited maximum antibacterial activity (25-32 mm) and Neem, turmeric exhibited 
moderate antibacterial activity and ginger exhibited comparatively lower activity.  In general, Gram
positive bacteria were more susceptible than Gram-negative bacteria. The results showed that the plant 
extracts differed statistically significantly (P < 0.05).  The findings demonstrate that the medicinal herbs 
have strong antibacterial properties and may be used in place of manufactured antibiotics.

---