PHYTOCHEMICAL SCREENING AND IN VITRO ANTIOXIDANT ACTIVITY OF CRATAEVA NURVALA STEM BARK
The aim and objective of the present study was to perform phytochemical screening and evaluation of in vitro antioxidant activity of Crataeva nurvala stem bark.The aqueous extract of Crataeva nurvala (AECN) was subjected to preliminary phytochemical screening to determine its chemical composition and was then refluxed with methanol to give a methanolic fraction (MF). The MF was analyzed by UV spectroscopy and TLC. The antioxidant activity of aqueous extract and its methanolic fraction was determined by in vitro models such as DPPH free radical scavenging assay, reducing power assay and total antioxidant capacity (TAC) by phosphomolybdenum method. Total phenolic and total flavonoid contents of aqueous extract and its methanolic fraction was determined colorimetrically by Folin-Ciocalteu and AlCl3 methods, respectively. Preliminary phytochemical screening of AECN showed the presence of alkaloids, glycosides, terpenoids, steroids, saponins, tannins, and flavonoids. Methanolic fraction (MF) indicated the presence of triterpenoids (Lupeol), steroids (β-sitosterol) and flavonoids (Gallic acid).The in vitro antioxidant assays proved that the methanolic fraction was found to be more potent as compared to the aqueous extract, which correlated with the higher content of phenolics and flavonoids present in methanolic fraction than that of the aqueous extract. The phytochemical screening and in vitro antioxidant assays prove that C. nurvala possesses potent antioxidant activity which may be attributed to the presence of important phytochemical compounds like flavonoids and phenolics