【作者】 李坤平；

【导师】 李卫民；

【作者基本信息】 广州中医药大学 ， 中药学， 2010， 博士

【摘要】 大孔树脂吸附中草药有效成份的基础理论研究对其产业化应用有着极其重要的意义。本文以黄芩黄酮和布渣叶黄酮为例,系统研究了大孔树脂对黄酮类化合物的吸附特性、吸附动力学和热力学、固定床和流态化吸附工艺,以及吸附过程的计算机模拟等共性问题。研究发现,在试验设定的条件下,大孔树脂对黄芩黄酮和布渣叶黄酮的吸附近似于单分子层吸附,Langmuir方程能很好地描述其等温吸附过程；其等量吸附焓变ΔH在-75～-5KJ.mol-1之间,其自由能变ΔG在-5～-2 KJ.mol-1之间,熵变在ΔS在-0.08～.0.01 KJ.mol-1.K-1之间；其特征分离系数RL在0～1之间,吸附过程属于自发进行的物理吸附。同时,在试验设定的条件下,Kannan粒子内扩散模型能较好地描述黄芩黄酮在AB-8和HPD-100树脂上吸附动力学过程；Lagergren一级动力学模型能很好地拟合布渣叶黄酮在D101、NKA和HPD300树脂上的吸附过程；其吸附受到膜扩散和颗粒内扩散影响,控制步骤为膜扩散过程。研究还发现,基于总黄酮分析的布渣叶黄酮的吸附过程有较好的吸附分离热力学和动力学规律,但受吸附质间相互作用影响,其中的牡荆苷和异鼠李素-3-0-β-芸香糖苷等成份的组分吸附动力学缺乏规律性。另外,通过对固定床吸附工艺和流态化吸附工艺的比较研究发现,由于降低了液膜扩散阻力,流态化平衡吸附时间明显缩短,流态化洗脱时间显著降低,对于D101树脂对黄芩黄酮的吸附研究中,10 min左右的流态化脱附率在90%以上。对布渣叶黄酮,采用固定床吸附工艺,当上样流速1.0 BV／h、洗脱流速2.0 BV／h、上样浓度2.0 mg／mL、洗脱剂用量2.8 BV和pH值7.8时,其纯度达到了61.77%,收率为80.25%。在研究过程中,本文提出了利用计算机软件模拟的虚拟筛选并预测吸附剂(大孔树脂)和吸附质(黄酮分子)的吸附作用研究新方法。在对聚苯乙烯骨架非极性树脂吸附黄芩苷和黄芩素的计算机模拟与实验研究发现,能通过等量吸附热、平均吸附量等参数预测树脂和化合物的吸附作用。研究成果为大孔树脂吸附中草药有效成份的研究和开发开辟了新的思路和方法,为其吸附动力学和吸附质组分的相互作用基础理论研究提供了新的途径。更多还原

【Abstract】 Fundamental research of the sorption of herbal active ingredient on macroporous resins plays an important role on its industrial application. As flavonids in Scutellaria baicalensis Georgi and Microcos paniculata L. as studied objects, this paper systemly inverstigated some common problems, such as the adsorption characteristic of macroporous resins on flavonoids, the sorption kinetics and thermodynamics, the fixed bed and fluidized bed sorption process, and the computer simulation of adsorption process.Study found that under the setted conditions, flavonids in Scutellaria baicalensis Georgi and Microcos paniculata L. sorption on macroporous resin similar monolayer adsorption, Langmuir equation could well describe their adsorption isotherms,which equivalent adsorption△H located between-75 and-5 KJ.mol-1, the free energy change△G at-5～-2 KJ.mol-1, the entropy change AS between-0.08 and-0.01 KJ.mol"1. K-1; its characteristic separation factor RL between 0 and 1, and the adsorption process of is the physical spontaneous adsorption process. Meanwhile, the Kannan model can describe the sorption kinetics of flavonoids in Scutellaria baicalensis Georgi on AB-8 and HPD-100 resin; and the adsorption process of flavonoids in Microcos paniculata L.on D101, NKA and HPD300 resin fitted the Lagergren kinetic model; their absorption process affected by the film diffusion and particle diffusion, but the control step is the film diffusion process. The study also found that the kinetics of total flavonoids adsorption fitted the general laws of thermodynamics and kinetics, but affected by the interaction between the adsorbates, while, the adsorption kinetics of vitexin and isorhamnetin-3-O-β-rutinoside lack of regularity.In addition, through a comparative study of the fixed bed adsorption process and the fluidization adsorption process, due to the reduction of the film diffusion resistance, the equilibrium adsorption time was significantly shorter and the elution time was significantly lower for the latter, the flavonoids in Scutellaria baicalensis Georgi adsorpted on D101 resin can elution down about 90% in 10 min. For the flavonoids in Microcos paniculata L. when feed flow rate 1.0 BV/h, elution flow rate of 2.0 BV/h, the sample concentration 2.0 mg/mL, eluent pH value of 7.8 and elution solution 2.8 BV, its purity reached 61.77%, yield of 80.25%.In the course of the study, this paper proposed a new method that using the computer software to simulate and predict the sorption process of adsorbents (macroporous resin) and adsorbate (flavonoid molecules). In the computer simulation and experimental study of the non-polar polystyrene skeleton resin and baicalin and baicalein, we found that the sorption process between the resins and compounds can be forecasted through the isosteric heat and average adsorption amouts, and other parameters of the process. The results can set a new way for the research and development of herbal active ingredients purification process by macroporous and provide some new ideas and methods for fundamental research on the population adsorption kinetics and adsorbate interaction of component during the sorption.更多还原