In-vitro antimicrobial and antioxidant activity of Argyreia cuneata (Willd.) Ker Gawl. (Convolvulaceae)

Abstract

Objectives: Argyreia cuneata (Willd.) Ker Gawl. belongs to the family Convolvulaceae. The present study was performed to screen the potential of crude extract of various parts of A. cuneata to exhibit antimicrobial activity. Methods: Extraction of shade dried and powdered leaf, stem and flower of A. cuneata was carried out by maceration technique. Antibacterial and antifungal activity of extracts was evaluated by Agar well diffusion and Poisoned food technique respectively. Antioxidant activity was determined by DPPH radical scavenging, ABTS radical scavenging and ferric reducing assays. Results: All extracts were effective in inhibiting test bacteria and the susceptibility of bacteria to extracts was in the order: Bacillus cereus > Shigella flexneri > Escherichia coli > Salmonella typhimurium. Leaf extract and stem extract exhibited highest and least antibacterial activity, respectively. Extracts were effective in causing inhibition of seed-borne fungi viz. Aspergillus niger and Bipolaris sp to >50%. Leaf extract exhibited marked antifungal activity followed by flower extract and stem extract. All extracts were shown to exhibit concentration dependent scavenging and reducing activity. Antioxidant activity of extracts observed was in the order: leaf extract > flower extract > stem extract. Conclusion: Among various parts of A. cuneata, leaf extract exhibited marked antimicrobial and antioxidant activity. The plant can be employed as an effective antimicrobial and antioxidant agent in suitable form. Further studies may be undertaken to recover phytochemicals from the plant and to investigate the antimicrobial and antioxidant activity of isolated components.
 Keywords: Argyreia cuneata, Maceration, Antimicrobial, Agar well diffusion, Poisoned food technique, Antioxidant