A Master’s thesis presented by student Taif Ridaa Salih from the Department of Biology, faculty of Science at the University of Kerbala, explored the inhibitory effectiveness of various antibiotics and natural plant-derived products against Pseudomonas aeruginosa and Candida albicans isolates obtained from different clinical sources.

The study aimed to isolate Pseudomonas aeruginosa bacteria and Candida albicans yeast from multiple clinical specimens and evaluate the antimicrobial activity of selected medicinal plant extracts—namely ginger, garlic, coriander, propolis, and myrrh. The research also assessed the inhibitory potential of combinations of each plant extract with ginger and investigated possible synergistic effects between the plant extracts and selected antibiotics to which the microorganisms had developed resistance.

Findings revealed that alcoholic plant extracts exhibited varying degrees of inhibitory activity against both bacterial and fungal isolates. Notably, combining these extracts with ginger enhanced their antimicrobial efficacy. The ginger-garlic combination demonstrated the highest inhibitory activity while maintaining an acceptable odor profile. However, ginger in combination with the other extracts did not show significant synergistic effects in terms of microbial inhibition.

The study recommended further investigation of these plant extracts at the molecular level to understand their mechanisms of action against bacteria and fungi. It also emphasized the need for cytotoxicity assessments to evaluate potential side effects on human cells, as well as studies focusing on the impact of these extracts—individually or in combination—on membrane integrity and virulence factors of the targeted pathogens.