2.3. Preparation of leaf extract

Aqueous leaves extracts of eucalyptus were prepared by collecting fresh leaves of eucalyptus from the Mianwali district. The leaves were thoroughly washed under running water with distilled water to remove dirt and impurities and allowed to completely dry in a shadow place for 25 to 30 days. After drying the samples were ground into fine powder in the kitchen blender. For the preparation of aqueous leaf extract, 10 g of dry leaf powder was added to 100 ml of distilled water. The mixture was then put on a hot plate at 60 °C for 30 min while being constantly stirred. The aqueous mixture was filtered using Whatman filter paper after cooling to room temperature and the extract was kept at 4 °C.