Phytochemical Analysis, Antibacterial, Antioxidant Activity Evaluation of Measa lanceolate Forssk Leaf Extracts and its Mediated Zinc Oxide Nanoparticles

Abstract

Measa lanceolata (family Myrsinaceae) is a medicinal plant traditionally used for the treatment of bacillary dysentery, bacterial infections, cholera, dermatoses, hepatitis, impetigo, neuropathies, sore throat as well as for treatment of some types of tapeworms and viral infections against different infectious diseases. To perform phytochemical screening, evaluate the antibacterial and antioxidant activity of Measa lanceolata leaf extracts and its mediated ZnO Nps. The plant samples were collected, dried, and the extraction of phytochemicals were done using the maceration method with methanol, distilled water, chloroform, and n-hexane solvents. Zinc Oxide nanoparticles were synthesized by mixing Zinc nitrate hexahydrate and plant extract. The synthesized nanoparticles were characterized by Fourier Transform Infrared Spectroscopy, X-ray Diffraction, Scanning Electron Microscope, and Ultraviolet-Visible spectroscopy. The antibacterial activities of the leaf extract and synthesized nanoparticles were evaluated by the disc diffusion method against selected human pathogenic bacteria. The minimum inhibitory concentration and minimum bactericidal concentration was determined for extracts against the selected pathogens using the broth dilution method. The antioxidant activity of the leaf extract was determined by using DPPH radical scavenging activity. The crystalline size and corresponding peak absorbance of synthesized Zinc Oxide Nanoparticles were 24.3 nm and 373.97, respectively. The results of the study showed that the leaf extracts contain alkaloid, flavonoid, phenol, saponin, steroid and tannin. The methanol, distilled water, chloroform, and hexane extracts showed good antibacterial activity and the maximum zone of inhibition (16.3 ± 0.88 mm, 15.0 ± 0.58 mm, 14.00 ± 1.00 mm, 9.3 ± 0.33 mm) against S. aureus respectively compared to Ciprofloxacin 22.5±0.88 mm. The synthesized Zinc Oxide Nanoparticles showed the highest zone of inhibition against E.coli (17.7 ± 0.62 mm) compared to Ciprofloxacin (21.6 ± 1.2 mm). In the present study, the Minimum Inhibitory Concentration and Minimum Bactericidal Concentration value obtained from distilled water extract has been found to be 12.5 mg/ml and 25 mg/ml against E.coli, respectively. The leaf extracts also exhibited high antioxidant activity with an IC50 value of 92.8 μg/ml compared to ascorbic acid 36.6 μg/ml. The results of this study therefore revealed that leaf extracts of Measa lanceolata posses antibacterial, antioxidant activity which justify use of this plant in the treatement of bacterial infections.