1.4.1. Estimation of total flavonoids
P. glandulosus leaves (10 g) were extracted in triplicate with 80% aqueous methanol (100 ml) at room temperature. The whole solution was filtered using Whatman filter paper no. 42. The filtrate was transferred to a crucible and evaporated to dryness and weighed to a constant weight (Ali et al ., 2019; Boham et al .,1994)