Institute of Organic and Analytical Chemistry (ICOA), University of Orléans, CNRS UMR7311, 45100 Orléans, France.
Molecules. 2023 Jul 18;28(14):5485. doi: 10.3390/molecules28145485.
The use of bioactive plant extracts in cosmetic products is a common practice. Most of these extracts are obtained by maceration in organic solvents, and depending on which solvents are used, the polarity and the structure of the target molecules will vary. Polyphenols are polar compounds that often display antioxidant and/or antibacterial activities. To extract them, ethanol/water mixtures are usually selected as green solvents. This solid-liquid extraction (assisted or not) requires the use of high volumes of solvents and many additional steps like mixing, agitation, filtration, and evaporation. Alternatively, supercritical carbon dioxide (SC-CO) offers many benefits for plant extraction: economical, non-toxic, and naturally concentrated extracts. However, its low polarity is not suitable to solubilize polar compounds. In this study, an experimental design was used to optimize supercritical fluid extraction (SFE) of caffeine and catechins from . Catechins are recognized for skin care use (antioxidant) and caffeine is also used for its skin care properties and to prevent excess storage of fat in cells. The temperature, modifier content, and water additive percentage were used as independent variables. The results showed that while the temperature was an insignificant parameter, a higher percentage of water (up to 20% in ethanol) and modifier favored the extraction of the polar target molecules. Additionally, the SFE results were compared with ultrasound-assisted extraction (UAE). Finally, a sequential selective extraction of caffeine from catechins is also presented.
植物生物活性提取物在化妆品产品中的应用较为常见。这些提取物大多通过有机溶剂浸提获得，而根据所使用的溶剂，目标分子的极性和结构会有所不同。多酚是具有极性的化合物，通常具有抗氧化和/或抗菌活性。为了提取它们，通常选择乙醇/水混合物作为绿色溶剂。这种固液提取（是否辅助）需要使用大量的溶剂和许多额外的步骤，如混合、搅拌、过滤和蒸发。相比之下，超临界二氧化碳（SC-CO2）为植物提取提供了许多优势：经济、无毒且天然浓缩提取物。然而，其低极性不利于溶解极性化合物。在这项研究中，使用实验设计来优化从 中提取咖啡因和儿茶素的超临界流体萃取（SFE）。儿茶素因其护肤用途（抗氧化）而广为人知，咖啡因也因其护肤特性和防止细胞中脂肪过度储存而被使用。温度、改性剂含量和水添加剂百分比被用作独立变量。结果表明，虽然温度是一个不重要的参数，但更高的水（乙醇中高达 20%）和改性剂百分比有利于极性目标分子的提取。此外，还比较了 SFE 结果与超声辅助提取（UAE）的结果。最后，还提出了从儿茶素中顺序选择性提取咖啡因的方法。
