Energy efficient extraction of medicinal and nutraceutical components with radio frequency and pulsed electric field combination

鬼臼毒素和皂苷是具有抗癌活性和重要药理作用的天然药用化合物。考虑到北美对包括鬼臼毒素和皂苷在内的医药和营养保健品的需求不断增长，开发更有效的提取工艺将满足迫切的商业需求。研究结果表明，射频（RF）加热和脉冲电场（PEF）辅助提取可以显著提高天然药物化合物（即鬼叶毒素和皂苷）的提取效率，从而在减少提取时间和溶剂消耗的情况下获得更高的产品收率。射频加热是一种新兴的加热技术，可在商业规模（直径达几米）的填料床溶剂萃取装置内提供均匀的体积内部加热。在填充床萃取装置中，所有颗粒和溶剂的均匀内部加热导致溶质在溶剂中的均匀溶解度。射频加热可以改善质量扩散，因为质量扩散系数随萃取温度呈指数增长。在pef辅助萃取中，细胞内部和细胞膜外部之间的电压差非常大，以至于细胞膜被破坏。因此，对溶质转移最重要的阻力，细胞壁，变得可以渗透溶质，然后弥散性和溶解度增加。RF-PEF辅助提取组合方法可以协同提高溶剂提取鬼臼毒素和皂苷等天然药用化合物的提取率。为了实现RF-PEF辅助填料床溶剂萃取生物成分（如鬼臼毒素和皂苷）的高效率，该研究项目将涉及实验设备的开发、RF和PEF萃取工艺的表征、RF-PEF辅助填料床溶剂萃取技术的化学性质表征、RF-PEF辅助填料床溶剂萃取技术的实验程序、与其他提取方法的比较、RF-PEF工艺的建模、仿真和优化。

Podophyllotoxin and saponins are natural medicinal compounds which have anticancer activity as well as other important pharmacological functions. Considering continuously growing demands for medicinal and nutraceutical products including podophyllotoxin and saponins in North America, the development of more efficient extraction processes would meet an urgent commercial demand.We propose that the extraction of natural medicinal compounds (i.e. podophyllotoxin and saponins) can be significantly improved with the aid of radio frequency (RF) heating and pulsed electric field (PEF) assisted extraction resulting in higher product yields at reduced extraction time and solvent consumption with high energy efficiency. RF heating is an emerging heating technology which provides uniform volumetric internal heating within a packed-bed solvent extraction unit at commercial scales (up to meters in diameter). Uniform internal heating of all particles and the solvent in the packed-bed extraction unit results in uniform solubility of the solute in the solvent. RF heating might improve mass diffusion because mass diffusivity increase with extraction temperature exponentially. In PEF-assisted extraction, the differential electric pressure between the cell interior and the exterior of the cell membranes is so large that the cell membranes are damaged. Therefore the most important resistance to solute transfer, the cell wall, becomes permeable to the solute and then the difrusivity and solubility increase. A combinational approach of RF-PEF assisted extraction can synergistically enhance the solvent extraction of natural medicinal compounds, including podophyllotoxin and saponins. To achieve high efficiencies in RF-PEF assisted packed-bed solvent extraction of bio-components (i.e. podophyllotoxin and saponins) the research project will involve experimental apparatus development, characterization of RF and PEF extraction processes, characterization of hinm^teriql properti^ experimental procedures for RF-PEF assisted packed-bed solvent extraction techniques, comparison with other extraction methods, and modeling, simulation and optimization of RF-PEF process.