睡莲多酚提取工艺优化及其抗油脂氧化作用

Extraction Optimization of Total Polyphenols from Nymphaea candida and Its Antioxidant Activity on Oil

探究睡莲多酚超声提取的最佳工艺条件,并在进一步纯化基础上,采用烘箱法评价其抗油脂氧化性能。以睡莲多酚提取率为指标,通过考察乙醇体积分数、料液比、超声温度、超声时间对提取的影响,结合正交设计实验优化得出最佳提取工艺:乙醇体积分数50%,料液比1∶50 g/mL,超声温度60℃,超声时间40 min,超声功率90 W,在此条件下睡莲多酚提取率达14.0%。通过大孔树脂聚酰胺联用方法获得了纯化后的睡莲多酚,其多酚质量分数为(79.29±0.75)%。抗油脂氧化实验结果表明:睡莲多酚对葵花籽油、菜籽油和猪油的过氧化均有良好的抑制作用,且其抗氧化性与其添加剂量呈正相关。此外,睡莲多酚分别与VC、和TBHQ复配后对猪油的过氧化均具有一定的协同增效作用,其中VC+睡莲多酚复配组的活性最强。本实验优选的工艺提取效率高,且发现睡莲多酚具有较好的抗油脂氧化能力,可延长食用油脂的货架期,说明该有效部位是一种值得开发的天然抗氧化剂。

To optimize ultrasonic extracting technique of total polyphenols from Nymphaea candida(NCTP),and its antioxidant activities of on sunflower seed oil,rap oil and lard were investigated by oven-drying method.In addition,polyphenols yield was taken as the index,the extracting technique of total polyphenols from N.candida was optimized by single factor test combined with orthogonal experiments,and the optimum extracting condition was shown as follows:ethanol concentration was 50%,feed-liquid ratio 1∶50 g/mL,ultrasonic temperature 60℃,ultrasonic time 40 min,ultrasonic power 90 W,Under this condition,the extraction rate of polyphenols was more than 14.0%.The extract further then was purified by macroporous resin polyamide,and the contents of polyphenol were(79.29±0.75)%in NCTP.Anti-lipid oxidation experimental results showed that NCTP had better antioxidant effect on sunflower seed oil,rapeseed oil and lard.NCTP and three oxidants(VC,citric acid and TBHQ)were shown better synergistic effect in the anti-lipid oxidation,of which activity of NCTP+VC was more than others.In conclusion,The present study improved the extraction yield of isostrictiniin and specified anti-lipid oxidant capacity of isostrictiniin,and demonstrated that isostrictiniin is a kind of natural antioxidant with evident development value.which could prolong the shelf life of edible fat and oil.Alos,it was found that water NCTP enjoyed a better anti-lipid oxidation ability,and could prolong the shelf life of edible oils.The results showed that NCTP was a kind of natural antioxidant worthy of research and development.