Chemical profiling, toxicity assessment, anti-diarrhoeal, anti-inflammatory and antinociceptive activities of Canarium schweinfurthii Engl. (Burseraceae) bark in rats

The bark of Canarium schweinfurthii is used in ethnomedicine for the treatment of diabetes, pain, malaria, fever and diarrhoea. The chemical phytoconstituents, antidiarrheal, anti-inflammatory and antinociceptive effects and safety profile of the aqueous extract of Canarium schweinfurthii bark (AECSB) were investigated. Gas chromatography-mass spectrometry (GC-MS) was used to analyse the phytochemical composition. In the acute toxicity test, AECSB were administered up to 2 g/kg by oral gavage. For the subacute toxicity test (28 days), rats in group 1 (control) received no AECSB, while rats in groups 2–4 were administered different doses of AECSB. Charcoal meal transit and castor oil-induced diarrhoea models were used to study the antidiarrheal effect, while egg albumin/carrageenan and acetic acid/tail immersion models were used for the anti-inflammatory and antinociceptive studies, respectively. With the exception of the acute toxicity experiment, AECSB was administered orally at doses of 200, 400 and 800 mg/kg. Bioactive phytoconstituents identified include p-cymene, δ-terpinene, linalool and phytol. No adverse effects or mortality were observed in acute and subacute studies. Treatment with AECSB (28 days) had no significant effect on organ weight, biochemical, hematologic and histopathologic parameters compared to the control groups (p > 0.05). Comparable antidiarrheal and antinociceptive effects were observed in both AECSB- and standard drug-treated groups, while the 400 and 800 mg/kg AECSB-treated groups showed remarkable anti-inflammatory effects compared to the standard drug-treated and control groups (p