Anti-inflammatory and Analgesic Activities of the Methanolic Extract and the Residual Fraction of the Stem Bark of Daniellia oliveri (Fabaceae)

Abstract
Aims: The aim of this study was to evaluate the anti-inflammatory and analgesic activities of Daniellia oliveri methanolic extract and its fractions in NMRI mice. Study Design: In vivo acute toxicity, anti-inflammatory and analgesic assays. Place and Duration of Study: The work was carried out in the Department of Traditional Pharmacopoeia and Pharmacy (MEPHATRA / PH) of the Research Institute for Health Sciences (IRSS) Ouagadougou (Burkina- Faso) between December 2020 and February 2021. Methodology: The toxicity of the extracts was assessed according to OECD guideline 423 of 2001 at a single dose of 2000 mg / kg body weight. Analgesic effect was evaluated on the number of abdominal contortions induced by the intraperitoneal injection of acetic acid and the anti-inflammatory activity using the Carrageenan anti-edematous test was determined according to Winter. Results: The results of the acute oral toxicity study in mice showed no clinical signs of toxicity at dose of 2000 mg/kg b.w. The lethal dose (LD50) value estimated to 5000 mg/kg. The extracts reduced edema from the first hour, then by the third hour and maximum inhibition was achieved by the fifth hour after the injection of carrageenan. Extract and methanolic fraction at different doses showed significant inhibition of abdominal contortions in mice in a dose dependent manner. At 200mg the analgesic effect of methanolic fraction and crude extract was 53.70±1.29% and 41.38±1.25% respectively. At 400 mg/kg, the methanolic fraction inhibited carragenaan-induced edema by 85.97±5.67%. Conclusion: Daniellia oliveri is an important source of anti-inflammatory and analgesic compounds, justifying the use of this plant in traditional medicine for the treatment of inflammatory diseases.