PDF(Pubmed)
Abstract：
Rosemary essential oil (REO) is widely recognized as a food flavoring and traditional herb and possesses potential antioxidant activity. However, its low yield rate and unclarified antioxidant mechanism warrant further investigation. In this study, an enzyme pretreatment-assisted extraction method with Box-Behnken design (BBD) and response surface methodology (RSM) models was employed to optimize the main factors of REO, and its antioxidant molecular mechanism under oxidative stress was elucidated in hydrogen peroxide-induced human lung carcinoma (A549) cells. The optimized yield (4.10%) of REO was recorded with the following optimum conditions: enzyme amount 1.60%, enzyme digestion pH 5.0, enzyme digestion temperature 46.50 °C, and enzyme digestion time 1.7 h. Meanwhile, 1.8-cineole (53.48%) and β-pinene (20.23%) exhibited radical scavenging activity higher than that of BHA and BHT. At the cellular level, REO (12.5-50 µg/mL) increased the levels of cell viability, CAT, SOD, and GSH significantly while reducing the contents of ROS, MDA, and GSSG, when compared to H2O2 exposure. Mechanically, REO relieved oxidative stress via activating the Nrf2 signaling pathway and enhancing the protein expression of Nrf2, NQO-1, and HO-1, which was further verified by molecular docking between the main component 1.8-cineole and the Kelch domain of KEAP1. Therefore, REO could be considered as a potent natural antioxidant with a potential strategy in the food and pharmaceutical industries.
摘要：
迷迭香精油(REO)被广泛认为是一种食品调味剂和传统草本植物,具有潜在的抗氧化活性。然而,其产率低，抗氧化机制不明，值得进一步研究。在这项研究中,采用Box-Behnken设计(BBD)和响应面法(RSM)模型的酶预处理辅助提取方法,并在过氧化氢诱导的人肺癌（A549）细胞中阐明了其在氧化应激下的抗氧化分子机制。在以下最佳条件下记录了REO的优化产率（4.10％）：酶量1.60％，酶消化pH5.0，酶消化温度46.50°C，和酶消化时间1.7h。同时，1.8-桉树脑（53.48％）和β-pine烯（20.23％）的自由基清除活性高于BHA和BHT。在细胞层面,REO（12.5-50µg/mL）增加了细胞活力水平，CAT,SOD,GSH在显著降低ROS含量的同时,MDA,和GSSG，与H2O2暴露相比。机械上,REO通过激活Nrf2信号通路并增强Nrf2、NQO-1和HO-1的蛋白表达来缓解氧化应激，这一点通过主要成分1.8-桉树脑与KEAP1的Kelch结构域之间的分子对接得到进一步验证。因此,REO可以被认为是一种有效的天然抗氧化剂，在食品和制药行业具有潜在的策略。
