Correlation between total flavonoid content and total phenolic content on antioxidant activity of ethanol extracts from three cultivars of papaya leaves

Abstract

The aim of this study was to elucidate the correlation between total flavonoid content and total phenolic content on antioxidants activity of ethanol extracts from three cultivars of papaya leaves: 'Holland,' 'Khak Dam' and 'Red Lady.' All crude extracts were investigated to find antioxidant capacity in DPPH radical scavenging.  The result indicated that the ethanol extract of ‘Red Lady’ papaya leaves exhibited the highest level of DPPH radical scavenging activity with the IC₅₀ of 0.18 mg/mL, followed by the ‘Khak Dam’ and ‘Holland’ papaya leaves having an IC₅₀ value of 0.24 and 0.44 mg/mL, respectively. The ethanol extract from 'Red Lady' papaya leaves showed the highest level of total flavonoid content (TFC) of 276.72 ± 1.04 µgQE/g DW and total phenolic content (TPC) of 169.85 ± 6.54 mgGAE/g DW. All three cultivars showed a distinctive correlation between IC₅₀ and the content of both total flavonoid and total phenolic with a negative relationship of Pearson’s correlation of -0.922 and -0.940, respectively.