Research Center of Henan Provincial Agricultural Biomass Resource Engineering and Technology, College of Life Science and Agricultural Engineering, Nanyang Normal University, Nanyang 473061, China.
Molecules. 2023 Nov 12;28(22):7554. doi: 10.3390/molecules28227554.
The development of natural antioxidants to replace synthetic compounds is attractive. leaves were proven to be rich in antioxidants. The extraction of antioxidants from Perilla leaves via ultrasonic-assisted extraction (UAE) based on choline chloride-based deep eutectic solvents (DESs) was studied. Firstly, several DESs were prepared, and their extraction effects were compared. Secondly, the extraction process was optimized by single-factor experiments and response surface methodology (RSM). Finally, the optimization results were verified and compared with the results of traditional solvent-based UAE. The effects of solvents on the surface cell morphology of leaves were characterized by scanning electron microscopy (SEM). Choline chloride-acetic acid-based DES (ChCl-AcA) extract showed a relatively high ferric-reducing antioxidant activity (FRAP) and 2,2-diphenyl-1-picrylhyldrazyl radical scavenging rate (DPPH). Under the optimal operating conditions (temperature 41 °C, liquid-solid ratio 33:1, ultrasonic time 30 min, water content 25%, ultrasonic power 219 W), the experimental results are as follows: DPPH64.40% and FRAP0.40 mM Fe(II)SE/g DW. The experimental and predicted results were highly consistent with a low error (<3.38%). The values of the DPPH and FRAP were significantly higher than that for the water, ethanol, and butanol-based UAE. SEM analysis confirmed that ChCl-AcA enhanced the destruction of the cell wall, so that more antioxidants were released. This study provides an eco-friendly technology for the efficient extraction of antioxidants from leaves. The cytotoxicity and biodegradability of the extract will be further verified in a future work.
开发天然抗氧化剂来替代合成化合物是很有吸引力的。紫苏叶已被证明富含抗氧化剂。本研究采用基于氯化胆碱的深共晶溶剂（DESs）的超声辅助提取（UAE）法从紫苏叶中提取抗氧化剂。首先，制备了几种 DESs，并比较了它们的提取效果。其次，通过单因素实验和响应面法（RSM）对提取工艺进行了优化。最后，验证了优化结果，并与传统溶剂基 UAE 的结果进行了比较。采用扫描电子显微镜（SEM）对溶剂对紫苏叶表面细胞形态的影响进行了表征。氯化胆碱-乙酸基 DES（ChCl-AcA）提取物表现出相对较高的铁还原抗氧化活性（FRAP）和 2,2-二苯基-1-苦基肼自由基清除率（DPPH）。在最佳操作条件（温度 41°C，液固比 33:1，超声时间 30 min，含水量 25%，超声功率 219 W）下，实验结果为：DPPH64.40%和 FRAP0.40 mM Fe(II)SE/g DW。实验和预测结果高度一致，误差较低（<3.38%）。DPPH 和 FRAP 的值明显高于水、乙醇和丁醇基 UAE 的值。SEM 分析证实，ChCl-AcA 增强了细胞壁的破坏，使更多的抗氧化剂释放出来。本研究为从紫苏叶中高效提取抗氧化剂提供了一种环保技术。在未来的工作中，将进一步验证提取物的细胞毒性和生物降解性。
