African Journal of
Pharmacy and Pharmacology

  • Abbreviation: Afr. J. Pharm. Pharmacol.
  • Language: English
  • ISSN: 1996-0816
  • DOI: 10.5897/AJPP
  • Start Year: 2007
  • Published Articles: 2227

Article in Press

Evaluation of the in-vitro antioxidant activity and acute toxicity of the alkaloidal constituents of Zanthoxylum Zanthoxyloides leaves

Thecla Okeahunwa AYOKA*, Ngwu NWACHUKWU, Aloysius Chinedu ENE, Chidi Uzoma IGWE, Charles Okeke NNADI

  •  Received: 17 November 2020
  •  Accepted: 21 December 2020
The study evaluated the antioxidant activities of both methanol (MeOH) extract and the bulk alkaloidal fraction of Zanthoxylum zanthoxyloides leaves and determined their median lethal dose in mice. The extract was subjected to solvent-solvent partitioning to obtain the bulk alkaloids from the methanol extract. The antioxidant activity of both the methanol extract and the bulk alkaloid fraction was measured in-vitro using DPPH radical scavenging; FRAP assays, as well as total antioxidant capacity (TAC) quantitation models. The MeOH extract (IC50 40.22 mg/L; EC50 32.08 µg/mL) and bulk alkaloid fraction (IC50 19.46 mg/L; EC50 30.27 µg/mL) showed significant (p < 0.05) antioxidant activities comparable with ascorbic acid (IC50 20.62 mg/L; EC50 32.51 µg/mL). The methanol extract and alkaloid fraction are relatively safe. No death was recorded on the mice upon oral administration of the extract/fraction at maximum dose of 5000 mg/kg. In conclusion, alkaloid constituents of Z. zanthoxyloides leaves have the potential to mop up free radicals in-vitro suggesting its high antioxidant potentials.

Keywords: Zanthoxylum zanthoxyloides, antioxidants, free radicals, alkaloids.