Phytochemical screening, antibacterial and anti-radical activities of Daniellia oliveri trunk bark extracts used in veterinary medicine against gastrointestinal diseases in Benin

Abstract

In Benin, pastoral activities contribute to food security. But the herds are often victims of gastrointestinal infections that decimated livestock and causing economic losses in this sector. The majority of farmers have recourse to herbal remedies to solve many animal health problems. This work aims to study the chemical composition and biological properties of Daniellia oliveri, plant revealed after ethnobotanical and ethnopharmacological surveys as a plant used by farmers to treat gastrointestinal diseases of their livestock. Results showed the presence of several secondary metabolites (alkaloids, leuco-anthocyanins, reducing compounds, saponin, tannins, mucilages, flavonoids, phenols, sterols and terpenes). Phenolic compounds contents vary according to the nature of the extraction solvent. However, the crude extracts showed lower anti-radical activity compared to ethyl acetate fractions (IC50 = 0.25μg / ml) and ethyl ether (IC50 = 0.06 μg / ml). The latter are more active than the synthetic compounds, BHA (IC50 = 4.8 μg / ml), quercetin (IC50 = 3 μg / ml) and gallic acid (IC50 = 0.9 μg / ml). The ethanol and hydroethanolic extracts of this plant showed bactericidal activity against Escherichia coliand Klebsiellapneumoniae. Twenty-two molecules were characterized from hydroethanolicextract of D. oliveri whose ethanoate glycerol, catechol and octadeca-9-enamide as major coumpound.