Abstract

Triplochiton scleroxylon is a tropical forest-tree species that is valued for its timber and also stem barks, whose aqueous extract is commonly used as an anti-diabetic preparation. Stem bark extracts (aqueous and 50% ethanol) and powder of T. scleroxylon were investigated for elemental and proximate compositions. Atomic absorption spectroscopy (Buck Scientific VGP 210) was used for elemental analysis. Standard analytical methods were utilized for proximate investigation of the powdered stem bark of T. scleroxylon. Heavy metals identified were present at tolerable levels, namely, cadmium (<0.01 ppm), lead (<0.08 ppm) and nickel (<0.05 ppm) in the stem bark powder, aqueous and 50% ethanol extracts. Calcium content of stem bark samples was higher than all other elements determined at approximately 2.60% while potassium followed with 1.32%. Magnesium was highest in 50% ethanol extract at 0.26% while zinc, copper and manganese were 6.45, 2.30 and 14.50 ppm respectively. Sodium content was only 0.01%. Proximate analysis of stem bark powder showed carbohydrate content of 80.70% and nitrogen free extract of 78.9%. Crude protein, fat and fibre contents were 5.90, 6.80 and 0.80% respectively. Percentage ash content was 6.92 while moisture content of the stem bark powder was 0.68%. Stem bark samples ofT. scleroxylon could be a good source of calcium and potassium to complement major sources. The use of the extracts in the treatment of diabetes mellitus in some parts of Nigeria is safe as heavy metals identified were present at sub-lethal levels. However, like all drugs, abuse of any form, is to be avoided.

Key words: Elemental, proximate, stem bark, Triplochiton scleroxylon.