로스팅 공정에 의해 향상된 우슬 뿌리 추출물의 항산화 및 미백 효과 = Roasting-Induced Enhancement of Antioxidant and Whitening Effects in Achyranthes bidentata Root Extracts

다국어 초록 (Multilingual Abstract)

Purpose: To explore the effects of roasting on the antioxidant and whitening activities of Achyranthes bidentata root extracts, targeting the changes in bioactive compounds. Methods: A. bidentata roots were roasted at 150°C and 200°C for 10, 20, and 30 min, followed by hot water extraction. The antioxidant activities (DPPH and ABTS radical scavenging), total polyphenol and flavonoid contents, and tyrosinase inhibition activities were evaluated. Chemical changes were assessed using UV-Vis, FT-IR, and HPLC-UV spectroscopy. Results: Roasting significantly enhanced the DPPH and ABTS radical scavenging activities, with the highest antioxidant activity recorded at 200°C for 30 min (13.54 and 16.18 mg AAE/g, respectively). The total polyphenol and flavonoid contents also increased markedly, from 1.35 mg GAE/g to 4.89 mg GAE/g and from 0.054 mg QE/g to 1.276 mg QE/g, respectively. Tyrosinase inhibition, initially negligible in unroasted extracts, showed a substantial increase after roasting, with the highest inhibition observed at 200°C for 30 minutes. Correlation and principal component analyses revealed strong positive relationships between the roasting conditions and bioactive compound levels. Additionally, UV-Vis spectroscopy identified increased absorption peaks related to polyphenols and melanoidin, whereas FT-IR and HPLC-UV fingerprint analyses confirmed significant chemical changes and formation of new compounds due to roasting. Conclusion: The study results demonstrated that the roasting process contributes to enhancing the antioxidant and whitening activities of A. bidentata root extracts, providing valuable foundational data for future studies on optimizing the roasting process to strengthen the bioactivity of natural materials, such as the A. bidentata roots.