Background: We investigated the optimal aqueous extraction conditions for recovery of high yields of total phenolic compounds from roots of Arctium lappa L. (burdock, Asteraceae), and we compared their antioxidant capacity.Methods and Results: The antioxidant activity of the extracts was tested using 2,2-diphenyl-1-picrylhydrazyl, 2,2’-azino-bis (3-ethylbenzothiazoline-6-sulfonic acid)-diammonium salt, and oxygen radical absorbance capacity assays. In addition, the major phenolic compounds present in the extracts were determined by high performance liquid chromatography analysis. Our results suggest that the roasted burdock 100°C, 15 min extract exhibited the strongest radical scavenging activity and possessed the highest concentration of phenolic compounds. The polyphenol content of both dried burdock and roasted burdock significantly increased with increase in the extraction temperature and time.Conclusions: These results indicated a relationship between phenolic compound levels in burdock and their free radical scavenging activities. This suggests that phenolic compounds significantly increase the antioxidant potential of burdock extracts.
율무의 볶음 온도와 시간이 율무 추출액의 품질특성에 미치는 영향을 분석하기 위하여 볶음공정을 반응표면분석법으로 최적화하였다. 볶음 온도와 시간이 증가함에 따라 추출액의 갈색도와 폴리페놀함량 및 DPPH 소거능이 증가하는 경향을 나타내었으며 색도는 붉은 색을 나타내었다. 측정된 변수에 대하여 수립된 회귀식은 높은 결정계수값을 가졌으며, 볶음시간 보다는 온도가 더 중요한 변수로 작용하였고, 수립된 이차 회귀식에 대한 적합성 결여분석 결과 수립된 반응