Effect of Aqueous Extract of Garcinia kola (Bitter Kola) Seed and Its Combination with Ocimum gratissimum (African Basil) Leaves in Diarrhoeal Rats

Introduction: Diarrhoea is characterized by frequent watery or loose stools mainly due to microorganisms, toxins, diets and allergies leading to dehydration and high mortality rate especially among children below five years. There is no scientific evidence to support the traditional use of Garcinia kola and Ocimum gratissimum to treat diarrhoea. This study aimed to investigate the effect of the aqueous extract of G. kola seed and its combination with Ocimum gratissimum leaves in castor oil-induced diarrhoeal rats. Methods: Lorke's approach was used to determine the acute toxicity (LD50) test. Castor oil-induced diarrhoeal rat models were used to test for intestinal motility and enteropooling to examine the extracts' antidiarrheal activity. Results: The lethal dose (LD50) results revealed that both plants were safe for therapeutic purposes. In the castor oil-induced diarrheal model, the extracts and their combination significantly (p<0.05) decreased fecal parameters and delayed the onset of diarrhoea in comparison to the negative control in a dose-dependent manner. When administered together, the extracts demonstrated a substantial (p<0.05) anti-motility impact at all tested doses in comparison to the negative control, according to the charcoal meal test. The enteropooling test results showed that the weight and volume of intestinal content decreased significantly (p<0.05) with graded doses of G. kola and its combination with O. gratissimum. Conclusion: The results suggest that the aqueous extract of G. kola and its combination with O. gratissimum have antidiarrhoea activity, although a more pronounced activity was observed when administered as a combination.