Physicochemical characteristics and antioxidant activity of Sumaeyaksuk depending on harvest times and processing methods

Abstract

Sumaeyaksuk (Artemisia Argyi H.) is one of the original mugwort spices in Namhae-gun, Korea. This study was conducted to investigate the physicochemical characteristics and biological activities of water extracts from dried and aging Sumaeyaksuk samples during the May-July harvest season. One (SD) was dried under shade for 12 days, while the other (AD) was aged for 7 days at 60℃ and then roasted for 220 minutes at over 90℃. Glucose was solely detected as a free sugar, and its SD and AD content were 0.42±0.02~0.43±0.01 g/100 g, and 0.41±0.02~0.47±0.04 g/100 g, respectively. The total phenolic contents of SD were 1.85±0.09~3.45±0.14 g/100 g, which were higher than those of AD (1.29±0.08~2.90±0.08 g/100 g). The antioxidant activities of the water extract powder from each Sumaeyaksuk were assessed by different in vitro methods, such as the DPPH and ABTS radical scavenging activity, FRAP, and decoloration prevention activity in β-carotene linoleic system. The DPPH and ABTS radical scavenging activity of AD extract were significantly higher than those of the SD extract (p<0.05). Moreover, at the concentrations of 31.25, 62.5, 125, 250, 500 μg/mL, the FRAP of the SD-May extract showed 1.67±0.58~489.90±7.59 μM, while the AD-July extract showed 9.70±1.07~590.40±7.45 μM. The β-carotene decoloration prevention activity of the SD-May and AD-July extracts were 25.53±2.85~81.43±2.56%, 35.98±2.22~79.00±1.42%, respectively. Based on these results, the extracts of SD-May and AD-July were promising as a functional food source due to their high antioxidant activites.