PRELIMINARY STUDIES ON THE NUTRITIONAL AND ANTINUTRITIONAL CONSTITUENTS OF SIX ACCESSIONS OF AFRICAN YAM BEAN (SPHENOSTYLIS STENOCARPA), AN UNDERUTILIZED LEGUME

摘要

African Yam Bean (AYB) (Sphenostylis stenocarpa) is an underutilized legume in Nigeria and Africa. This study evaluates the proximate analysis, mineral constituents, and antinutritional factors (ANFs) of six accessions of AYB, (TSS 10, TSS 57, TSS 84, TSS 95, TSS 96 and TSS 111) from the International Institute of Tropical Agriculture (I.I.T.A), Ibadan, Nigeria. All the analyses were done using standard methods. Statistical analysis was done using one-way ANOVA. Results of proximate analysis show that the following AYB accessions had the highest data; crude protein 26.60+0.14% (TSS 95), crude fat 3.10+0.14% (TSS 96), crude fibre 4.40+0.00% (TSS 10), ash 3.10+0.14% (TSS 95), gross energy 4.558+0.01Kcal/g (TSS 95), dry matter 94.75+0.7 (TSS 57) and moisture 6.36+0.61(TSS 10). Minerals results show that the following AYB accessions had the highest figures: calcium 0.289±0.00% (TSS 96); magnesium 0.161±0.00% (TSS 10); potassium 0.720±0.00% (TSS 95); phosphorus 0.206 ± 0.00% (TSS 95); sodium 591.88±0.00mg/g (TSS 57); iron 89.98±0.00mg/g (TSS 84) and copper 16.10±0.00mg/g (TSS 84). The following accessions recorded the highest values of ANFs: tannin 0.009±0.00% (TSS 84); saponin 0.139±0.01% (TSS 84); oxalate 0.116±0.00% (TSS 84); trypsin inhibitor 15.92±0.26% (TSS 57); phytate 0.2000±0.00% (TSS 111) and alkaloids 15.015±0.01% (TSS 57). This study concludes that AYB is rich in crude protein and crude fibre, however, the ANFs need adequate processing for adequate utilization as human foods and animal feeds