Ivanović Milena, Krajnc Peter, Mlinarič Aleš, Razboršek Maša Islamčević
Faculty of Chemistry and Chemical Engineering, University of Maribor, Smetanova ulica 17, SI-2000 Maribor, Slovenia.
Marifarm, Proizvodnja in Storitve d.o.o., Minařikova ulica 8, SI-2000 Maribor, Slovenia.
Plants (Basel). 2022 Dec 11;11(24):3468. doi: 10.3390/plants11243468.
In the present study, vortex-assisted matrix solid-phase dispersion (VA-MSPD) extraction was used to isolate the major bioactive compounds from . To reduce the negative environmental impact of the conventionally used organic solvents, four different choline chloride-based natural deep eutectic solvents (NADES) were investigated as possible eluents. The most influential VA-MSPD extraction parameters: stationary phase (adsorbent), adsorbent/sample ratio, vortex time, and volume of extraction solvent were systematically optimized. Ultrasound-assisted extraction with 80% MeOH was used as the standard method for the comparison of results. The stability of the obtained extracts was studied over a period of 0 to 60 days at three different temperatures (-18 °C, 4 °C, and 25 °C). All extracts were evaluated both spectrophotometrically (determination of total phenolic content (TPC) and antioxidant activity by ABTS and FRAP assay) and chromatographically (HPLC-UV). NADES based on choline chloride and lactic acid (ChCl-LA) was selected as the most effective extractant, with a determined TPC value of its extract of 38.34 ± 0.09 mg GA/g DW (27% higher than the methanolic VA-MSPD extract) and high antioxidant activity. The content of individual phenolic compounds (chlorogenic acid, dicaffeoylquinic acid isomers, naringenin isomers, and chalcones) in the ChCl-LA extract, determined by HPLC-UV, was comparable to that of the conventionally obtained one. Moreover, the stabilization effect of ChCl-LA was confirmed for the studied compounds: chlorogenic acid, naringenin-4'-O-glucoside, tomoroside A, naringenin-5-O-glucoside, isosalipurposide, and naringenin. The optimum VA-MSPD conditions for the extraction of polyphenols were: florisil/sample ratio of 0.5/1, a vortex time of 2 min, and an elution volume of ChCl-LA of 10 mL.
在本研究中，采用涡旋辅助基质固相分散（VA-MSPD）萃取法从……中分离主要生物活性化合物。为减少传统使用的有机溶剂对环境的负面影响，研究了四种不同的基于氯化胆碱的天然低共熔溶剂（NADES）作为可能的洗脱剂。对最具影响力的VA-MSPD萃取参数：固定相（吸附剂）、吸附剂/样品比、涡旋时间和萃取溶剂体积进行了系统优化。以80%甲醇的超声辅助萃取作为比较结果的标准方法。在三种不同温度（-18℃、4℃和25℃）下，对所得提取物在0至60天的时间内进行稳定性研究。所有提取物均通过分光光度法（通过ABTS和FRAP法测定总酚含量（TPC）和抗氧化活性）和色谱法（HPLC-UV）进行评估。基于氯化胆碱和乳酸的NADES（ChCl-LA）被选为最有效的萃取剂，其提取物的TPC值为38.34±0.09mg GA/g DW（比甲醇VA-MSPD提取物高27%），且具有高抗氧化活性。通过HPLC-UV测定，ChCl-LA提取物中各酚类化合物（绿原酸、二咖啡酰奎尼酸异构体、柚皮苷异构体和查耳酮）的含量与传统方法获得的提取物相当。此外，证实了ChCl-LA对所研究化合物（绿原酸、柚皮苷-4'-O-葡萄糖苷、托莫罗苷A、柚皮苷-5-O-葡萄糖苷异水杨苷和柚皮苷）具有稳定作用。提取多酚的最佳VA-MSPD条件为：弗罗里硅土/样品比为0.5/1，涡旋时间为2分钟，ChCl-LA的洗脱体积为10mL。
