Antioxidant activity and phytochemical screening of stem bark extracts of Grewia optiva Drummond ex Burret

Abstract

Medicinal plants are traditionally used in Pakistan and in other countries for treatment of various diseases. Grewia optiva is a medicinal plant used in northern Pakistan for various diseases. This plant was assessed for various parameters like total phenolic content (TPC), total flavonoid content (TFC) and total antioxidant capacity (TAC) using ABTS radical scavenging assays. Phytochemical tests are also included in the study to identify various classes of phytochemicals. Phytochemical tests resulted in the presence of secondary metabolites like alkaloids, terpenoids, tannins, saponins and flavonoid. TPC analysis showed phenolic content in extract and its fractions with maximum value in aqueous fractions 167.3 mg/g followed by n-butanol 132.5 mg/g while the lowest value was recorded in chloroform fraction 89.9 mg/g respectively with comparing to Gallic acid equivalent. Results of TFC quantitative estimation exhibited presence of flavonoids in aqueous fraction with maximum value of 84.2 mg/g followed by crude extract 81.9 mg/g while the lowest value was recorded chloroform fraction 42.6 mg/g respectively as compare to Quercetin equivalent. TAC revealed promising antioxidant potential of the crude extract and its fractions with high activity in again aqueous fraction 1.55 mg/g followed by crude extract 1.52 mg/g while the lowest value was recorded in chloroform fraction 0.82 mg/g respectively by comparing to the standard trolox. From the result is concluded that plant have various phytochemical compound and further study should be made to isolate the compounds and check for different activity.