Effect of Extraction Method on Antioxidant Determination in Produce by Differential Pulse Voltammetry

摘要

Due primarily to the many health benefits associated with a diet high in antioxidants, numerous assayshave been developed to determine antioxidant content of foods. However, most are time-consumingand costly. This paper presents an electrochemical technique as a simple, sensitive and cost-effectivealternative to traditional assays, and uses the presented technique to determine the optimal method forthe extraction of antioxidants from produce samples. In this study, fresh carrot, tomato, rhubarb,raspberry, strawberry, red bell pepper, green bell pepper and yellow bell pepper samples weresubjected to three different extraction methods: aqueous extraction, using phosphate buffer as theextraction solvent; organic extraction, using acidified methanol as the extraction solvent; and solventless extraction, using a Breville home juicer. Extracts were then analyzed by differential pulsevoltammetry (DPV). Differences in the potential and area of the principal peak, indicative ofantioxidant activity and capacity respectively, were analyzed to determine the effect of extractionmethod on antioxidant measurement. Aqueous extraction was found to provide the most effectiveextraction relative to antioxidant activity, while organic extraction was most effective relative to-4 -4 antioxidant capacity. Limits of detection and quantitation were 1.9 x 10 mol/L and 6.5 x 10 mol/L,respectively. This study showed DPV to be a sensitive and effective technique for antioxidantdetermination.