Antioxidant, Antimicrobial and Cytotoxic Potential of Selected Medicinal Plants Collected from Khanewal Valley, Pakistan

The increasing demand for novel therapeutics as antimicrobial and anti-oxidant agents, renaissance the interest towards medicinal plants. Based on their long-term application, there is a general belief that herbal remedies are safe. The research was conducted to evaluate the antimicrobial, antioxidant, and cytotoxic properties of Medicago denticulata, Terminalia arjuna, Pyrus pashia and Schinus molle. These plants were collected from district Khanewal and their extracts were tested for antimicrobial activity against ATCC (American Type Culture Collection) strains of Bacillus spizizenii, Staphylococcus aureus, Staphylococcus epidermidis, Escherichia coli and Salmonella typhimurium using well diffusion method. Antifungal activity was performed against Aspergillus niger, Aspergillus flavus, Fusarium solani, Aspergillus fumigatus and Mucor using the agar tube dilution method. The extracts were also tested for their antioxidant activity using 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical-scavenging assay and cytotoxic activity using brine shrimp. Among all the plants, T. arjuna fruit extract exhibited the highest antibacterial activity against S. aureus and B. spizizenii (MICs 82µg/100µl and 162µg/100µl) and Gram-negative bacteria with MICs >1.5mg/100µl. All the tested strains of fungi were inhibited by T. arjuna. In the DPPH assay, the extract of S. molle showed free radical scavenging at a concentration of 16µg/ml while effective (>80%) scavenging free radical activities of P. pashia and T. arjuna leaf extract were at a concentration of 161 µg/ml. Cytotoxicity against brine shrimp larvae was reported only for the extract from T. arjuna fruit and root. The therapeutic potential of the plants studied, provides scientific evidence for the support of using M. denticulata, T. arjuna, P. pashia and S. molle in traditional medicine and these plants have potential applications as bioactive agents for the treatment of various diseases.