Nutrients composition and functional properties of oil palm syrup, aqueous extract of kola nut and their mixtures

Abstract

In this study, oil palm (Elaeis guineensis) syrup, aqueous extracts of kola nut (Cola acuminata) and their mixtures (decoction of C. acuminata in 20 % oil palm syrup solution) were investigated using suitable biochemical procedures. The proximate analysis of oil palm syrup and C. acuminata revealed the values of moisture, crude protein, fat, ash, fibre and nitrogen free extract of oil palm syrup were 29.55 %, 0.50 %, 2.34 %, 2.32 %, 0.00 % and 65.29 % while values for the C. acuminata were 44.70 %, 17.50 %, 2.45 %, 1.91 %, 8.86 % and 24.58 %. Also, the total carbohydrate constituted 66.29 % when determined by anthrone method. The pH and titratable acidity values were within the acidic range. The syrup, C. acuminata and its mixture extracts recorded high reducing power, total phenolic and vitamin C contents. The IC50 values of α-amylase inhibitory activity for aqueous solutions of palm syrup, aqueous extracts of C. acuminata and its mixture extract were 0.51, 4.50 and 12.10 % respectively. The 2, 2-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging activity of aqueous solutions of oil palm syrup, aqueous extracts of C. acuminata and its mixture extracts revealed IC50 values of 8.44, 3.29 and 6.60 %. The results of this study suggest that the decoction of C. acuminata in 20 % syrup solution had synergistic effects with respect to in vitro antioxidant properties and alpha amylase inhibitory potential, and further indicates that the studied extracts could elicit potential nutritional and health benefits.