Department of Analytical Chemistry, Faculty of Sciences, University of Granada, C/Fuentenueva s/n, 18071 Granada, Spain; Faculty of Chemistry and Chemical Engineering, University of Maribor, Smetanova ulica 17, SI-2000 Maribor, Slovenia.
Department of Analytical Chemistry, Faculty of Sciences, University of Granada, C/Fuentenueva s/n, 18071 Granada, Spain; Area of Food Technology, Regional Institute for Applied Scientific Research (IRICA), University of Castilla-La Mancha. Avda. Camilo José Cela, 10, 13071 Ciudad Real, Spain; Research and Development of Functional Food Centre (CIDAF), PTS Granada, Avda. Del Conocimiento 37, Bioregión Building, 18016 Granada, Spain.
Food Res Int. 2018 Sep;111:67-76. doi: 10.1016/j.foodres.2018.05.014. Epub 2018 May 8.
Natural deep eutectic solvents (NADESs) have been postulated as alternative green solvents for the isolation of valuable bioactive compounds from Lippia citriodora. Thus, 11 different NADESs, based on choline chloride (ChCl) as the hydrogen bond acceptor in combination with different hydrogen bond donors (organic acids, polyalcohols, sugars, and urea) were tested. According to the results obtained, ChCl-lactic acid exhibited the highest extraction yield for iridoids, 7.25 mg g, phenylpropanoids, 17.23 mg g, and flavonoids, 9.02 mg g being significantly greater than phenylpropanoid and flavonoid yields, 15.63 and 5.43 mg g respectively, extracted with methanol as conventional solvent. Subsequently, in order to optimise the most influential microwave assisted extraction (MAE) parameters, a Box-Behnken design paired with a response surface methodology were implemented. Temperature and water content showed a strong effect on the extraction of polyphenol sub-classes, while the effect of irradiation time was less noticeable on extraction yields. Temperature of 63.68 °C, a water content of 32.19% and a microwave irrdiation time of 17.08 min were the optimum conditions provided by the statistical program. The use of NADESs showed potential to facilitate the design and customisation of green tailor-made solvents which have greater extraction capacity than conventional organic solvents.
天然深共晶溶剂（NADES）被认为是从柠檬香脂中分离有价值的生物活性化合物的替代绿色溶剂。因此，测试了 11 种不同的 NADES，以氯化胆碱（ChCl）作为氢键受体，与不同的氢键供体（有机酸、多元醇、糖和尿素）结合。根据所得结果，ChCl-乳酸对环烯醚萜类化合物的提取率最高，为 7.25mg/g，对苯丙素类化合物的提取率为 17.23mg/g，对类黄酮的提取率为 9.02mg/g，明显高于苯丙素类化合物和类黄酮的提取率，分别为 15.63mg/g 和 5.43mg/g，用甲醇作为常规溶剂提取。随后，为了优化最具影响力的微波辅助提取（MAE）参数，采用 Box-Behnken 设计与响应面法相结合。温度和含水量对多酚亚类的提取有很强的影响，而辐照时间对提取产率的影响则不那么明显。温度为 63.68°C、含水量为 32.19%和微波辐照时间为 17.08 分钟是统计程序提供的最佳条件。NADES 的使用显示出在设计和定制绿色定制溶剂方面具有潜力，这些溶剂比传统有机溶剂具有更大的提取能力。
