摘要:人參含有許多種具有廣泛生物機能的活性成分。然而因為人參的細胞壁結構堅硬,阻礙溶劑滲 透,所以在萃取人參的生物活性成分時常效率低落與費時。為了促進萃取的效率,微波、超音波、超 臨界流體和超高壓技術已被用來輔助人參活性成分的萃取。然而,已有研究指出許多人參中天然化合 物是熱不穩定的,在熱加工過程中可能會裂解。常壓低溫電漿具有很強的表面蝕刻能力,有作為非熱 輔助萃取技術的潛力。與超音波、微波等新型輔助萃取技術的原理相似,在萃取過程中,低溫電漿技 術很可能透過破壞細胞壁結構來提高萃取劑的滲透效果。 儘管尚未有低溫電漿在輔助萃取中的應用 結果,此方法在理論上仍然是絕對可行的,且在未來會是一個能用來替代熱輔助的萃取方法。在此計 畫中我們的目標為發展新型噴射式常壓低溫電漿萃取技術,並將其應用於人參萃取,以評估此方法在 從固體植物基質中萃取出生物活性成分的效率。此計畫會連續執行三年。在第一年我們會系統性地研 究加工參數對於人參物理化學性質的影響,為往後的萃取應用找出最適的加工條件。在第二年會根據 萃取物的產率及其生物活性成分以評估低溫電漿在協助以有機溶劑萃取人參生物活性成分的成效。最 後在第三年會利用低溫電漿萃取方式萃取水溶性生物活性成分,並評估其生物活性。一旦此計畫完 成,我們絕對會成為此研究領域的先驅,同時奠定了未來應用低溫電漿技術萃取的重要基礎。
Abstract: Ginseng is a slow-growing perennial plant that contains wide variety of biologically active constituents that exhibited wide array of biological functionalities. However, the extraction of bioactive component from ginseng is most of the time difficult, inefficient and time consuming due to its rough cell wall structure that blocks the solvent penetration. To improve extraction efficiency, microwave, ultrasound, supercritical fluid, and ultra high pressure techniques have been used to assist extracting bioactive component from ginseng. However, many of the natural compounds in ginseng were reported to be thermally unstable and may degrade during heat processing. Thus, it becomes an emerging interest among investigators to find an alternative extraction method operating at low temperature that could avoid thermal damage and optimally preserve the bioactive components in the extract.
Atmospheric cold plasma that was found to have strong surface etching and striping ability could potentially fit into the niche of non-thermal technologies assisting the extraction process. Previous results showed that cold plasma treatment on plants and grains could change their physiochemical properties, which allowed better solvent absorbing capacity. In food science field, cold plasma technology has been investigated in the packaging material modification, food decontamination, depolymerization, chemical and texture modification. According to previous investigations, cold plasma treatment can cause immediate disruption of cell wall structure and, thus, has been widely investigated as novel food sterilization method. Analogously, during extraction processing, cold plasma technology is very probable to enhance solvent penetration through disrupting cell wall structure similar to other novel technology assisted extraction methods, such as ultrasound and microwave. Even though, the reports on the application of cold plasma have not yet been presented, but this method is definitely theoretically feasible and could be a good alternative to the thermal assisted extraction methods in future.
In this project, we aim to develop a novel extraction technology assisted by atmospheric cold plasmas jet using ginseng to evaluate the efficiency of such method to extract the bioactive components from the solid plant matrix. This project will be executed in three consecutive years. During first year, the effect of processing parameters, such as operating power, treatment time, carrier gas, sample distance, and release mode (pulse or continuous), on the physiochemical properties of ginseng will be studied systematically for finding the optimum processing condition for later extraction application. In the second year, the efficiency of cold plasma assisted organic solvent extraction of the ginseng bioactive components will be evaluated based on the yield and bioactivities of the extract. Finally, in the third year, the water soluble bioactive components will also be extracted using cold plasma extraction method and evaluated using similar methods to the organic solvent extracted compounds. Upon completion of this project, we will definitely become a world pioneer in this research field and lay the important fundamentals for the future application of cold plasma technology in the extraction processing.