1. The hypoglycaemic effect of fermented seeds of Parkia biglobosa (PB; African 
locust bean), a natural nutritional condiment that features frequently in some 
African diets as a spice, was investigated in the present study in 
alloxan-induced diabetic rats. Its effect was compared with that of 
glibenclamide (Daonil; Sanofi-Aventis, Paris, France), a reference antidiabetic 
drug. The effects of PB on lipid profiles were also examined. 2. In order to 
assess the hypoglycaemic and hypolipidaemic effects of aqueous and methanolic 
extracts of PB on experimental animals, fasting plasma glucose (FPG), total 
cholesterol, triglyceride, high-density lipoprotein (HDL) and low-density 
lipoprotein (LDL) were determined. In addition, the weight of each animal was 
determined to assess any possible weight gain or loss in the experimental 
animals (diabetic rats treated with Daonil (group C), the aqueous extract of PB 
(group D) or the methanolic extract of PB (group E)) compared with control 
groups (non-diabetic (group A) and non-treated diabetic (group B)). 3. A single 
dose of 120 mg/kg, i.v., alloxan administered to rats resulted in significant 
increases in the FPG (P < 0.001) of test animals compared with controls. 
However, dietary supplementation with PB (6 g/kg extract for 4 weeks 
administered orally using an intragastric tube) ameliorated the alloxan-induced 
diabetes in a manner comparable with that of the reference antidiabetic drug 
glibenclamide. Aqueous and methanolic extracts of PB (6% w/w) elicited 69.2% and 
64.4% reductions, respectively, in FPG compared with 70.4% in 0.01 mg/150 g 
glibenclamide-treated rats. 4. Although animals treated with the aqueous extract 
of PB gained weight in manner similar to normal controls, animals given the 
methanolic extract and glibenclamide lost weight in manner similar to 
non-treated diabetic rats. In addition, high levels of HDL and low LDL were 
observed in animals treated with the aqueous extract of PB, a pattern similar to 
that seen in normal controls. Low levels of HDL and high levels of LDL were 
observed in animals treated with the methanolic extract of PB, a pattern similar 
to that seen in non-treated diabetic controls. 5. The results of the present 
study demonstrate that both aqueous and methanolic extracts of fermented seeds 
of PB exert a hypoglycaemic effect; hence, PB has an antidiabetic property. 
However, only the aqueous extract of PB ameliorated the loss of bodyweight 
usually associated with diabetes. Although the aqueous extract has a favourable 
lipid profile, which is probably an indication of its possible anti-arteriogenic 
property (hypertension and ischaemic heart diseases being common complications 
in diabetes mellitus), the methanolic extract shows possible contraindication to 
ischaemic heart diseases.