The Antioxidant Potential of Ethanol Extract of Yacon (Smallanthus sonchifolius) Tuber Based on Ferric Reducing Antioxidant Power (FRAP) and Cupric Reducing Antioxidant Capacity (CUPRAC) Assays
DOI:
https://doi.org/10.29313/bcsms.v5i3.21659Keywords:
Yacon, Natural antioxidants, FRAP, CUPRAC, Ethanol extractAbstract
Abstract. Antioxidants play a vital role in neutralizing free radicals that trigger oxidative stress and contribute to degenerative diseases such as cancer, diabetes, and cardiovascular disorders. Growing public awareness of the risks associated with synthetic antioxidants has increased the demand for natural, safe, and environmentally friendly alternatives. The yacon tuber (Smallanthus sonchifolius), a member of the Asteraceae family, contains bioactive compounds—mainly phenolics and flavonoids—known for their strong antioxidant activity. This study aimed to assess the antioxidant potential of ethanol extracts of yacon tubers using two metal ion–reducing assays: Ferric Reducing Antioxidant Power (FRAP) and Cupric Reducing Antioxidant Capacity (CUPRAC). The extract was obtained through maceration in 95% ethanol and concentrated at 65°C. The FRAP assay measures the reduction of Fe³⁺ to Fe²⁺ under acidic conditions, whereas the CUPRAC assay evaluates the reduction of Cu²⁺ to Cu⁺ under neutral conditions. All methods were measured by spectrophotometer. The antioxidant capacity of ethanol extracts of yacon tubers using the FRAP method was 16.22 ± 0.15 mg AAE/g and CUPRAC method was 4.54 ± 0.20 mg AAE/g. This indicates that the yacon ethanol extract has the iron and copper reduction capacity. The yacon can thus be considered a promising natural source of antioxidants for pharmaceutical and nutraceutical development.
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