CULTIVAR COMPARISON: PROXIMATE, PHYTOCHEMICAL, GCMS AND FTIR ANALYSES OF AQUEOUS EXTRACTS FROM WHITE AND YELLOW DioscoreadumetorumTUBERS

Abstract

Yams of the genus Dioscorea, particularly Dioscoreadumetorum (bitter yam), are staple foods in several West African countries, including Nigeria and Ghana. It is known for trifoliate leaves and significant nutritional value, bitter yam plays a crucial role in food security due to its high starch content (approximately 75%) and balanced amino acid profile. This study investigates the proximate composition, phytochemical profile, and chemical constituents of white and yellow Dioscoreadumetorum tubers using Gas Chromatography-Mass Spectrometry (GC-MS) and Fourier Transform Infrared (FTIR) spectroscopy. Ash, lipid and carbohydrate were more abundant in the yellow specie while moisture, fibre, and protein were more significant in the white specie. Saponins, alkaloids, tannins, flavonoids, steroids, and phenols were all detected in both cultivars. The yellow specie contained more alkaloid, tannin, flavonoid and steroid than the white specie. Saponins were however more abundant in the white cultivar. GCMS-derived 9-Octadecenoic acid,Hexadecanoic acid, and Dodecanoic acid were identified in both cultivars.Alcohols, carboxylic acids, esters, ethers were among the functional groups common to both tubers. The findings support the nutritional and therapeutic use of these tubers, highlighting their potential to address dietary needs and improve food security in the region.