Extraction, fractionation and assessment of antioxidant activities of active components of Aframomum sceptrum seeds

Abstract

A simple procedure of extraction, fractionation and assessment of organoleptic and antioxidant properties of Aframomum sceptrum seeds was carried out, and the results were compared with a currently used synthetic antioxidant, butylated hydroxy toluene (BHT). Extraction was carried out using Soxhlet extractor and fractionation of the ethanolic extract was accomplished using vacuum liquid chromatography (VLC). Various fractions of the ethanolic extract were obtained but similar fractions were pooled together to yield six fractions (F1-F6) as guided by thin layer chromatography (TLC) analysis. Fractions obtained were subjected to sensory, chemical, spectroscopic and storage assessment in order to evaluate their antioxidant potentials. Sensory characterization and antioxidant storage tests showed that fractions F4 and F5 had non-bitter taste and yellow colour in contrast to bitter taste and dark brown colour of the crude extract. Statistical analysis (P= 0.05)  showed that the antioxidant effectiveness (AE) of the fractionated extracts F4 and F5 were 62.57 and 59.13% for groundnut oil and 64.50 and 62.91% for red palm oil, respectively, and compared favourably with the standard synthetic antioxidant used. The fractions can be used to extend the shelf life of food products.   Key words: Spices, fractionated extracts, antioxidant effectiveness, active components, sensory and   spectroscopic characteristics.