铁皮石斛花总黄酮的绿色提取工艺优化

目的:为充分利用铁皮石斛花中的黄酮类物质，开发了一种绿色高效的总黄酮提取工艺。方法:以铁皮石斛花总黄酮得率为指标，使用新型低共熔溶剂，基于单因素实验结合响应面法（Response surface methodology, RSM）优化总黄酮提取工艺参数，并使用大孔吸附树脂考察溶剂的循环利用能力。结果:氯化胆碱、乙二醇（摩尔比1:4）组成的低共熔溶剂（Deep eutectic solvents，DESs）得率最高；最佳提取条件下（DESs含水量18.9%，温度88.2 ℃，液固比23.3:1 mL/g，时间38.0 min），得率达到22.457 mg/g；大孔吸附树脂ADS-8对总黄酮吸附率、解吸率分别为78.32%、83.55%，回收后的DESs重复利用率达95.47%。结论:低共熔溶剂是一种高效绿色的提取方法，可循环利用铁皮石斛花中总黄酮的提取。

Optimization of Green Extraction Process of Total Flavonoids from Dendrobium officinale Flower

Objective: To make full use of the flavonoids in Dendrobium officinale flowers, a green and efficient extraction process was developed. Methods: Taking the yield of flavonoids from Dendrobium officinale flowers as an index, using new deep eutectic solvents, based on single factor experiments and response surface methodology, the extraction process of total flavonoids was optimized. And macroporous adsorption resins were used to investigate the recycling capacity of DESs. Results: DESs composed of choline chloride and ethylene glycol (molar ratio 1:4) had the highest yield. The yield reached 22.457 mg/g under the optimal extraction conditions (water content 18.9 %, temperature 88.2 ℃, liquid-solid ratio 23.3:1 mL/g, time 38.0 min). The adsorption rate and desorption rate of ADS-8 for total flavonoids were 78.32% and 83.55%, respectively, and the recycling rate of recovered DESs reached 95.47%. Conclusion: The deep eutectic solvent was an efficient and green method that could be recycled to extract the total flavonoids from Dendrobium candidum flowers.