恰玛古黄酮的提取纯化及抗氧化活性分析

Extraction, Purification, and Antioxidant Activity Analysis of Flavonoids from Brassica rapa L.

摘要:

为了探索一种高效环保的新疆恰玛古黄酮提取方法，该研究制备并对比了5种不同的低共熔溶剂（Deep Eutectic Solvents, DES），采用超声波辅助DES提取法，确定了最佳提取工艺。通过单因素试验考察摩尔比、含水量、超声时间、超声温度、料液比对恰玛古黄酮含量的影响，并采用响应面法进一步优化提取条件。在此基础上，利用AB-8大孔吸附树脂纯化恰玛古提取液，考察恰玛古黄酮体外抗氧化活性。结果表明，提取恰玛古黄酮的最佳提取工艺条件为：DES组成为氯化胆碱-丙三醇、DES摩尔比1:2、DES含水量20%、超声时间41 min，超声温度40 ℃，料液比1:40，在此条件下恰玛古黄酮含量达到9.66 mg/g，经纯化后达到11.32 mg/g，提高了17.18%。当恰玛古黄酮纯化液质量浓度为100 μg/mL时，ABTS+和DPPH自由基清除率达到48.24%和35.20%，IC50值为124.41和272.98 μg/mL，吸光度达到0.45，表明抗氧化能力和总还原能力较强。本研究为恰玛古黄酮作为功能活性成分在食品行业中的应用提供科学依据。

Abstract:

Five deep eutectic solvents (DES) were prepared, their extraction performances were compared, and the optimal extraction process was determined using ultrasonic-assisted DES extraction to explore an efficient and environment-friendly method to extract flavonoids from Brassica rapa L. sourced from Xinjiang. The effects of DES molar ratio, DES water content, ultrasonic time, ultrasonic temperature, and solid-to-liquid ratio on the content of B. rapa flavonoids were examined through single-factor experiments. Subsequently, response surface methodology was used to optimize the extraction conditions further. The B. rapa extract was purified using AB-8 macroporous adsorption resin, and the in vitro antioxidant activity of B. rapa flavonoids was investigated. The results showed that the optimal extraction conditions were as follows: a DES composed of choline chloride and glycerol at a molar ratio of 1:2, with a water content of 20%, an ultrasonic time of 41 min, an ultrasonic temperature of 40 ℃, and a solid-to-liquid ratio of 1:40. Under these conditions, the content of B. rapa flavonoids was 9.66 mg/g, and it reached 11.32 mg/g after purification, indicating an increase by 17.18%. When the mass concentration of purified B. rapa flavonoid solution was 100 μg/mL, the ABTS+ and DPPH radical scavenging activities reached 48.24% and 35.20%, respectively, and the IC50 values were 124.41 and 272.98 μg/mL, respectively. The absorbance of the solution reached 0.45, suggesting stronger antioxidant and total reducing capacities. This study provides a scientific basis for the application of B. rapa flavonoids as functional active ingredients in the food industry.