Abstract

Eight deep eutectic solvents composed of choline chloride and various acids were used to synthesize chitosan derivatives. All acidic deep eutectic solvents resulted in high transmittance and stable chitosan derivatives under the appropriate reaction conditions. Choline chloride–oleic acid–chitosan provided the best performance and was used for the ultrasound-assisted extraction of rutin, quercetin, and isorhamnetin from sea buckthorn (Hippophae rhamnoides L.) leaves coupled with reversed-phase high-performance liquid chromatography (RP-HPLC). The extraction provided recoveries of 107.5 ± 0.16 rutin, 30.22 ± 0.37 quercetin, and 43.5 ± 0.22 isorhamnetin mg g⁻¹dry powder using the optimal conditions at 41 °C, solid/solvent ratio of 1:24 g mL⁻¹, and six adsorption/desorption cycles. The linear range was from 1.0 to 1000.0 µg mL⁻¹ and the limits of detection (LODs) for rutin, quercetin, and isorhamnetin were 0.12, 0.16, and 0.23 µg g⁻¹, respectively. The results showed that sea buckthorn (H. rhamnoides L.) leaves, a food industry by-product, may be used as an inexpensive source of flavonoids.

摘要

采用八种由氯化胆碱和各种酸组成的低共熔溶剂合成壳聚糖衍生物。在适当的反应条件下，所有酸性低共熔溶剂均产生高透光率和稳定的壳聚糖衍生物。氯化胆碱-油酸-壳聚糖的性能最佳，用于超声辅助从沙棘叶中提取芦丁、槲皮素和异鼠李素，并结合反相高效液相色谱法（RP-高效液相色谱法）。在 41 °C 的最佳条件下，固体/溶剂比为1:24 g ^{mL -1}，和六个吸附/解吸循环。线性范围为 1.0 至 1000.0 µg mL ^-1，芦丁、槲皮素和异鼠李素的检测限 (LOD) 分别为 0.12、0.16 和 0.23 µg g ^-1。结果表明，食品工业的副产品沙棘（ H. rhamnoides L. ）叶可作为一种廉价的类黄酮来源。