牛蒡低聚果糖的提取条件及其稳定性研究

On the extraction process and stability of burdock oligosaccharide

目的:研究牛蒡低聚果糖的最佳提取条件及其稳定性。方法:通过单因素实验及正交实验对牛蒡低聚果糖的提取条件进行优化,采用蒽酮法测定其在不同条件下的稳定性。结果:牛蒡低聚果糖最佳提取条件为固液比1∶25、提取温度80℃、提取时间90 min,在此条件下,牛蒡低聚果糖得率为67.54%。牛蒡低聚果糖热稳定性及光照条件下稳定性较好,易被氧化,在pH>8或pH<4及含有Cu^(2+)、Fe^(3+)溶液中的稳定性较差。结论:牛蒡低聚果糖在存储过程中应避免与空气及铁铜制品直接接触,提取时温度应低于90℃,且溶液无强酸碱性。

Objective： To investigate the optimal conditions for extracting the oligosaccharide from burdock and stability of the extracts. Methods： Singlefactor experiment and orthogonal test were used to optimize the extraction conditions for burdock oligosaccharide,and the stability of the extracts was determined under diverse conditions using anthrone method. Results： The optimal conditions for extracting the oligosaccharide from burdock were： solid/liquid ratio 1∶25,temperature at 80℃,extraction time for 90 min. This condition yielded burdock oligosaccharide by 67.54%. The stability for burdock oligosaccharide was better when heated or lighted,yet the extract was susceptible to oxidation,and the stability appeared poorer when stored in solution with p H8 or p H4 or containing Cu^（2＋） or Fe^（3＋）. Conclusion： Burdock oligosaccharide should be stored at room temperature and isolated from oxygen without antioxidant supplement,and be free of direct contact with iron or copper during the extraction process. The extraction process must be under 90℃,and kept from solution with strong acidity and alkaline.