Background: Vernonia amygdalina, commonly called bitter-leaf, is widely consumed in many parts of Africa, and Nigeria, in
particular. The leaf extract has been reported to have antimicrobial, anti-plasmodial, anti-helminthic, as well as prebiotic properties,
but its immuno-modulatory effects have not been well-studied, neither have the prebiotics been identified. This study evaluated the
immuno-modulatory properties of the aqueous leaf extract and identified the prebiotic components.
Methods: The immuno-modulatory potential was evaluated by monitoring the effects of oral administration of the extract on
immunological, haematological and lipid profiles of
Rattus norvegicus
, while the prebiotic components were identified by thin layer
chromatography (TLC), following liquid-liquid fractionation of the extract.
Results: Consumption of the extract caused significant increases in CD4
+-, white blood cell-, total lymphocyte- and high density
lipid (HDL) counts; decreases in low density lipid (LDL) and triglycerides and no significant effect on haemoglobin (Hb) and
packed cell volume (PCV) in the blood of test animals. The water-soluble fraction of the extract contained most of the phytoconstituents
of the extract and Thin Layer Chromatographic analysis of the fraction revealed the presence of fructo-oligosaccharide
and galacto-oligosaccharide prebiotics.
Conclusion: The results from this study have shown that the aqueous leaf extract of
V. amygdalina has positive immune-modulatory
and haematologic effects and contains some important prebiotic compounds.
