Author(s): Vijay Thirugnanasambandan*, Sarumathy Kannayiram

To investigate phytochemical properties, free radical scavenging and antimicrobial activity of medicinal plant Grewia umbelliferea fruit and root extracts. Methods: Dried, powdered fruit and root were extracted by Soxhlet apparatus with successive solvent extraction method. The filtrates were used for preliminary phytochemical analysis, radical scavenging assays (DPPH, ABTS and FRAP) and antimicrobial studies (Agar well diffusion method). Results: Preliminary phytochemical analysis clearly confirmed the Grewia umbelliferea fruit contains of phenolics, tannin and flavonoids. Acetone extract of fruit showed significant antioxidant scavenging activity in DPPH (20.0 µg/ml), ABTS (41343.51 µM TE/g extract) and FRAP (4713.33 mM Fe (II)/mg extract) assays. Acetone extract of fruit indicated highest inhibitory activity (IZ 22.6 mm) against K. pneumonia at 200 mg/mL. The lowest inhibitory activity (IZ 2.0 mm / 100mg/mL) against bacterial species were showed by hot water extract of root against S. pneumoniae. Except the hot water extract all other extracts were resist the Aspergillus sp at different inhibitory zone levels from 0.5 to 14.0 mm which depends upon their concentration. Conclusion: The acetone extract of Grewia umbelliferea fruit and root has revealed the presence chemical compounds which are responsible for its antioxidant and antimicrobial activity. Keywords: Grewia umbelliferea, Phytochemical, Antioxidant and Antimicrobial activity