To develop polysaccharide products from macadamia green husk,improve integrated utilization of macadamia green husk,the extraction rate of polysaccharide from different parts of macadamia fruit was com-pared.Effects of microwave power,extraction time,solid-to-liquid ratio and ultrasonic temperature on the ex-traction rate of polysaccharide were compared by ultrasonic-microwave assisted extraction methods using one-factor and orthogonal test to study the best extraction conditions.The scavenging capacity against 1,1-diphen-yl-2-picrylhydrazyl(DPPH)and hydroxyl radicals,and reducing power were investigated to evaluate its an-tioxidant activity by comparing with vitamin C as control.The results showed that the extraction rate of poly-saccharides from macadamia green husk was the highest in different parts of macadamia fruit.Effects of all factors of ultrasonic-microwave assisted extraction process on extraction rate could be ranked from high to low as following:extraction time,solid-to-liquid ratio,ultrasonic temperature and microwave power.There were extremely significant differences among all the factors.The optimal extraction condition was as following:ex-traction time of 90 min,ultrasonic temperature of 65℃,solid-to-liquid ratio of 1:25(g/mL),microwave power of 400 W.Under this condition,the extraction rate of polysaccharide from macadamia green husk was up to 1.96%.The antioxidant activities of macadamia green husk polysaccharide was extremely positive corre-lated to mass concentration(p＜0.01),with correlation coefficients of 0.970 7,0.981 3 and 0.991 2,respec-tively,with strong scavenging capacities against DPPH and hydroxyl radicals and reducing power,and with half maximal inhibitory concentration(IC50)of 38.55,20.38 and 41.51 μg/mL,respectively,which were lower than vitamin C at the same concentration.
关键词
澳洲坚果/青皮多糖/提取/超声波/微波/抗氧化
Key words
macadamia nut/polysaccharide from green husk/extraction/ultrasonic/microwave/antioxidant activity
维普
万方数据