Concentration And Separation Of Activity Components From Natural Product Using Ionic Liquid-modified Silica

There are four parts in this paper.Chapter 1 In this section, the application of silica supported ionic liquids in various fields were reviewed.And the significance and direction of the research were also elucidated.Chapter 2 Three kinds of silica supported ionic liquids possessing of different anions SiO2·Im+·Cl-, SiO2·Im+·PF6- and SiO2·Im+·BF4- were synthesized, and were characterized by IR, ICP, thermogravimetric analysis and elemental:analysis.Chapter 3 Using the silica supported ionic liquid SiO2·Im+·Cl- synthesized above as absorbent, the effects of adsorption time, solid-liquid ratio, sample concentration, flow rate on the adsorption properties of silica supported ionic liquids SiO2-Im+·Cl-for flavonoids were investigated in this paper. The results indicated that the adsorption equilibrium for tested compounds was achieved within 30 min, the adsorption efficiencies of these three compounds were found to improve with the increase of solid-liquid ratio, and decrease with the increase of their concentrations. Moreover, the adsorption isotherm data of the three tested compounds were in good concordance with the Langmuir model. The saturated adsorption capacity of SiO2·Im+·Cl- for genistein, luteolin and quercetin was 47.7 mg·g-1,52.5 mg·g-1,63.2 mg·g-1 respectively. Adsorption efficiency of SiO2·Im+·Cl- could reach more than 90% at a sample flow rate of 0.5-1.5 mL·min-1. Using methanol as eluent, the saturated desorption efficiencies of genistein, luteolin and quercetin were 86.1%, 83.3%,84.6% respectively. The elution order of the three tested flavonoids was genistein, luteolin and quercetin. SiO2·Im+·Cl- had strong adsorption and separation capacity for three tested flavonoids, which was hopeful to be applied in separation and purification of naturally occurring flavonoids.Chapter 4 The concentration and separation of silica supported-ionic liquids SiO2·Im+·Cl-, SiO2·Im+·BF4- and SiO2·Im+·PF6- for the activity components of Daphne odora var.marginata were studied, and the optimum separation condition of different silica supported-ionic liquids, residues and recycling use of the ionic liquid-modified silica were mainly investigated. The results indicated that the optimum elute conditions was methanol to ethyl acetate 1:5 and methanol in turns for SiO2·Im+·Cl-, while it was methanol to ethyl acetate 1:20 for SiO2-Im+-BF4-. They both had a certain degre concentration separation capacity to biflavones and there was only a little difference between them except that SiO2·Im+·Cl- had fairly good effect to concentration separation daphnoretin However SiO2·Im+·PF6- almost had no concentration separation capacity to activity components of Daphne odora var.marginat. The highest total concentration rate of SiO2·Im+·Cl-/BF4- could still reach 66.7%,65.8% for biflavones and daphnoretin respectively, but there was no significant difference between them. The residues of ionic liquid-modified silica in optimum elute components are low arid the ionic liquids-modified silica was recycled two times without obvious loss in the concentration separation capacity.