海娜色素的提取工艺及稳定性

Extraction and stability of henna pigments

在单因素试验基础上,采用响应面分析法确定超声提取海娜色素的最佳工艺条件:使用pH 13的氢氧化钠水溶液在30℃提取60min,该工艺条件下的实际提取率为2.73%。通过测定460nm处的吸光度考察了碱性和加热对海娜色素稳定性的影响,pH 7海娜色素溶液在室温、45、70℃下84h内吸光度没有明显变化;而在pH 13溶液中的海娜色素稳定性差,室温、45、70℃下放置的溶液在第84h吸光度分别降至69%、56%和30%。

Abstract. Based on the single factor experiment, response surface methodology was used to optimize the extraction process of pigments from Henna. The results showed that the optimum extraction process was sodium hydroxide solution at 30 ℃ and pH 13 for 60 rain, and the yield was 2.73%. The effect of alkaline and heat on the stability of Henna pigments was studied by spectrophotometry at 460 nm. The solutions absorbance at pH 7 were stable in 84 h at room temperature, 45 and 70 ℃, while those at pH 13 was reduced to 69%, 56%, and 30% at 84 h, respectively.