Abstract

Recently, there has been an increase in global acclaim for historically utilized medicinal plants. This study aimed to prepare 70% ethanolic extracts from various medicinal plants and evaluate their phytochemical profiles, antimicrobial properties, and antioxidant activities. Twelve medicinal plant samples (six flowers and six leaves of same medicinal plant) (Rhododendron arboreum, Hibiscus rosa sinensis, Rosa damascena, Tagetes erecta, Bougainvillea glabra and Chrysanthemum grandiflorum) were collected and processed. Standard procedures were employed to assess the phytochemical composition of these extracts. Antimicrobial activity was evaluated using the agar well diffusion method, while antioxidant capacity was determined using the DPPH (1,1-diphenyl-2-picrylhyrazyl) assay. Phytochemical screening revealed the presence of alkaloids, coumarin, glycosides, flavonoids, tannins, quinones, reducing sugars, and saponins in most of the extracts. Notably, R. damascena, T. erecta, and R. arboreum demonstrated antimicrobial activity against Staphylococcus aureus (ATCC 6538P), with R. damascena showing the strongest inhibition across all concentrations (100, 200, 300, and 400 mg/ml), with the highest inhibition zone of 20 mm at 400 mg/ml. However, no extracts displayed antibacterial activity against Klebsiella pneumoniae, Pseudomonas aeruginosa, or Escherichia coli. Regarding antioxidant activity, ascorbic acid had an IC50 value of 7.928 µg/ml, while the plant extracts showed varying levels of antioxidant potential, with R. damascena leaf extract having the lowest IC50 value of 21.10 µg/ml and C. grandiflorum leaf extract showing the highest IC50 value of 241.21 µg/ml. These findings indicate that the selected plants possess antimicrobial and antioxidant properties, and their phytochemical content may contribute to their therapeutic potential.