Abstract— In the present study, three medicinally significant plant species, viz., Artemisia absinthium, Matricaria chamomilla, and Thymus vulgaris, were selected for qualitative screening of phytochemicals, and crude extracts of the plants were used to evaluate their antimicrobial activity against Staphylococcus aureus. The aerial parts of the species were sequentially extracted with ethyl acetate and reconstituted with 70% ethanol; qualitative analysis was planned for detection of the presence of major phytochemicals. Disk diffusion method was used to evaluate the antibacterial activity of all the three extracts at different concentrations. Phytochemical screening results indicated the presence of different secondary metabolites, viz., alkaloids, flavonoids, phenols, glycosides, and terpenoids. Disk diffusion assay results indicated that Thymus vulgaris showed high-level antibacterial activity even at low concentrations, with increasing inhibition zones of 8.95 mm at 0.1 mg/ml to 22.65 mm at 100 mg/ml; Matricaria chamomilla showed the highest inhibition zone of 35.80 mm at 100 mg/ml, showing high efficacy at high concentration, while Artemisia absinthium showed moderate activity, with inhibition zones of 0.90 mm at 0.1 mg/ml to 8.90 mm at 100 mg/ml. The results indicate that all three plant extracts contain potential secondary metabolites that could be used as preventive agents in the diet of fish to inhibit bacterial infection.
Sani et al. (Sat,) studied this question.