Antioxidant, Phytotoxic and Antiurease Activities, and Total Phenolic and Flavonoid Contents of Conocarpus lancifolius (Combretaceae)
Purpose: To evaluate the antioxidant, phytotoxic and anti-urease properties of dichloromethane and methanol extracts of Conocarpus lancifolius in correlation with total phenolic and flavonoid contents.
Methods: The whole plant (dried aerial parts and root) of Conocarpus lancifolius was extracted successively with dichloromethane, methanol and water at room temperature. Antioxidant activity was determined by DPPH, Nitric oxide scavenging and FRAP methods. Phytotoxicity was performed by Lemna minor assay and analyzed relative to control with effective dose (ED50) to determine FI50 values (concentration necessary to inhibit 50 % frond proliferation) and 65 % confidence intervals. Urease inhibitory activity was assessed at a concentration of 125 μg/mL by Berthelot reaction with slight modification. Total phenolic contents were calculated with reference to gallic acid equivalent and confirmed by Folin and Ciocalteau’s phenol method. Total flavonoid was determined with reference to quercetin.
Results: The DPPH and hydroxyl radical scavenging activities of the methanol extract were 93.35 %. The phytotoxicity of the methanol extract was 90 % growth regulation while the anti-urease inhibitory activity was 91.1 % with half-maximal inhibitory concentration (IC50) of 49.1 ± 1.3 μg/mL. Total flavonoid contents of dichloromethane extract was 629.4 ± 1.57 μg/mL. The phenolic content of the extract calculated with reference to quercetin, gallic acid, chlorogenic acid, ferulic acid and 4-hydroxy 3-methoxy benzoic acid equivalent was 45.772, 9.779, 70.304, 74.93 and 57.80 ppm, respectively.
Conclusion: The results confirm that Conocarpus lancifolius extracts possess some antioxidant, phytotoxicity and anti-urease potentials due to its phenolic and flavonoid contents.
Keywords: Antioxidant, Phenolics, Falvonoids, Phytotoxicity, Anti- urease, Conocarpus lancifolius