金刺梨黄色素提取条件及稳定性研究

Studies on the extraction process and its stability of yellow pigment from Rosa sterilis D.shi

以金刺梨果实为原料,通过提取剂筛选和均匀设计等试验确定金刺梨黄色素的提取条件,分析光照、pH、氧化剂、还原剂、金属离子、糖等物质对其稳定性和抗氧化能力的影响。结果显示:金刺梨黄色素的最佳提取条件为:以80%丙酮为提取剂,料液比1:16(g/mL),提取温度58℃,提取时间3.5h,提取2次。金刺梨黄色素在日光下虽不稳定,但仍有较强的抗氧化能力,在pH 5~7时色泽和抗氧化能力较稳定;H_2O_2破坏黄色素的色泽和抗氧化能力,Na_2SO_3可显著提高其吸光值、FRAP和TRPA;对Zn^(2+)、Cu^(2+)、K^+、Mg^(2+)、Na^+和Al^(3+)等金属离子较稳定,对Fe^(3+)不稳定,所试金属离子对金刺梨黄色素抗氧化能力均有一定影响;葡萄糖、蔗糖和麦芽糖等对金刺梨黄色素色泽影响不大,麦芽糖可提高其FRAP。

The extraction conditions of yellow pigment from Rosa sterilis D.shi were optimized by extraction agent screening and uniform experimental design,and the effects of light,pH,oxidant,reducing agent,metal ions and sugar on their stability and antioxidant capacity was investigated.The optimum extraction conditions of Ca melliaoleifera cake were obtained as follows：80% acetone,the ratio of material to liquid is 1：16（g/mL）,each time ultrasonic assisted extraction for 3.5 hat 58 ℃,and extraction 2 times.The yellow pigment was unstable in the sunlight,but showing a strong antioxidant capacity.Yellow pigment and its antioxidant capacity was relatively stable in the pH 5～7.H2O2 destroyed the color and its antioxidant capacity of yellow pigment.Na2SO3 could significantly increase the absorbance,FRAP and TRPA of yellow pigment.It was stable to Zn^2＋,Cu^2＋,K^＋,Mg^2＋,Na^＋ and Al^3＋,but unstable to Fe^3＋,the tested metal ions had a certain effect on antioxidant capacity of yellow pigment.Glucose,sucrose and maltose had little effect on stability of yellow pigment,while maltose could improve the FRAP.