Altemimi Ammar, Lightfoot David A, Kinsel Mary, Watson Dennis G
Department of Plant, Soil and Agricultural Systems, Southern Illinois University, Carbondale, IL 62901, USA.
Department of Food Science and Biotechnology, College of Agriculture, University of Basrah, Basrah 61004, Iraq.
Molecules. 2015 Apr 14;20(4):6611-25. doi: 10.3390/molecules20046611.
The extraction of lutein and β-carotene from spinach (Spinacia oleracea L.) leaves is important to the dietary supplement industry. A Box-Behnken design and response surface methodology (RSM) were used to investigate the effect of process variables on the ultrasound-assisted extraction (UAE) of lutein and β-carotene from spinach. Three independent variables, extraction temperature (°C), extraction power (%) and extraction time (min) were studied. Thin-layer chromatography (TLC) followed by UV visualization and densitometry was used as a simple and rapid method for both identification and quantification of lutein and β-carotene during UAE. Methanol extracts of leaves from spinach and authentic standards of lutein and β-carotene were separated by normal-phase TLC with ethyl acetate-acetone (5:4 (v/v)) as the mobile phase. In this study, the combination of TLC, densitometry, and Box-Behnken with RSM methods were effective for the quantitative analysis of lutein and β-carotene from spinach extracts. The resulting quadratic polynomial models for optimizing lutein and β-carotene from spinach had high coefficients of determination of 0.96 and 0.94, respectively. The optimal UAE settings for output of lutein and β-carotene simultaneously from spinach extracts were an extraction temperature of 40 °C, extraction power of 40% (28 W/cm3) and extraction time of 16 min. The identity and purity of each TLC spot was measured using time-of-flight mass spectrometry. Therefore, UAE assisted extraction of carotenes from spinach can provide a source of lutein and β-carotene for the dietary supplement industry.
从菠菜（Spinacia oleracea L.）叶中提取叶黄素和β-胡萝卜素对膳食补充剂行业很重要。采用Box-Behnken设计和响应面方法（RSM）研究了工艺变量对菠菜中叶黄素和β-胡萝卜素超声辅助提取（UAE）的影响。研究了三个自变量，即提取温度（℃）、提取功率（%）和提取时间（分钟）。在UAE过程中，采用薄层色谱（TLC）结合紫外可视化和密度测定法作为鉴定和定量叶黄素和β-胡萝卜素的简单快速方法。以乙酸乙酯-丙酮（5:4（v/v））为流动相，通过正相TLC分离菠菜叶甲醇提取物以及叶黄素和β-胡萝卜素的标准品。在本研究中，TLC、密度测定法以及Box-Behnken与RSM方法的结合对菠菜提取物中叶黄素和β-胡萝卜素的定量分析有效。用于优化菠菜中叶黄素和β-胡萝卜素的二次多项式模型的决定系数分别高达0.96和0.94。从菠菜提取物中同时提取叶黄素和β-胡萝卜素的最佳UAE条件为：提取温度40℃、提取功率40%（28 W/cm³）、提取时间16分钟。使用飞行时间质谱法测定每个TLC斑点的身份和纯度。因此，UAE辅助从菠菜中提取类胡萝卜素可为膳食补充剂行业提供叶黄素和β-胡萝卜素来源。
