柴达木枸杞类胡萝卜素提取工艺优化及抗氧化活性研究

以柴达木枸杞子为材料,采用超声波辅助溶剂提取方法,在单因素实验的基础上,应用Box-Behnken Design对料液比、提取溶剂配比、提取时间进行优化,并通过DPPH自由基清除实验研究类胡萝卜素的抗氧化活性,同时测定不同产地、不同采摘期柴达木枸杞类胡萝卜素含量。通过响应面分析优化后,得出超声波辅助提取柴达木枸杞中类胡萝卜素的最佳工艺条件为:提取溶剂为石油醚∶无水乙醇（v/v=2.6∶1）,料液比为1∶60（g/m L）,提取时间41 min,提取次数1次,在此条件下,类胡萝卜素的含量可达321.52 mg/100 g。柴达木枸杞中类胡萝卜素DPPH自由基清除率IC50为34.09μg/m L,柴达木枸杞类胡萝卜素具有较好的抗氧化活性并且不同产地、不同采摘期柴达木枸杞类胡萝卜素含量均存在显著差异（p<0.05）。 

Extraction optimization and antioxidant activity for carotenoid in Qaidam Chinese wolfberry

The Qaidam Chinese Wolfberries were used as the raw material in carotenoid extracting. In order to improve extraction content,the method of ultrasonic- assisted organic solvent extraction was adopted. Based on the single factor experiments,solid- liquid ratio,the ratio of the extraction solvent and the extraction time were optimized by Box- Behnken Design. The inhibitory rate of DPPH scavenging activity was analyzed antioxidant activity of carotenoid.Under optimal extraction conditions,the contents of carotenoid in Qaidam Chinese Wolfberry from different producing areas and different picking period were determined.By the optimizing of response surface method,the optimalizing technique was obtained,which was that the extraction solvent was petroleum ether and ethanol mixtures( v / v = 2.6 ∶ 1),the solid- liquid ratio was 1 ∶ 60( g / m L),extraction time and extraction times were41 min and 1,respectively. The content of carotenoid in Qaidam Chinese wolfberry was 321.52 mg /100 g under optimized conditions.The half maximal inhibiting concentration( IC50) of DPPH scavenging activity of carotenoid was34.09 μg / m L. There were statistically significant differences in carotenoid content in Qaidam Chinese Wolfberry compared with different producing areas and different picking period( p < 0.05).