| Ginkgolic acids are a kind of active component in Ginkgo biloba L besides ginkgolides and ginkgoflavone, they have antimicrobial, antiinflammation, antitumor and worm killing effects thus they have research value and they can be made into medicine cosmetic and biopesticide. Ginkgolic acids are 6-alkyl salicylic acids with saturated or up to triple unsaturated n-Cu to n-Cn-alkyl residues, which constitute the major component of the lipid fraction in the sarcotesta of Ginkgo biloba L. In our country the resource of the sarcotesta of Ginkgo biloba L is abundance and it is always wasted. In this paper, the separation, purification and quantitative, qualitative determination of ginkgolic acids in the sarcotesta of ginkgo biloba L were studied, the main conclusions are as follow:l.The pharmacognosy of the sarcotesta of Ginkgo biloba L was studied, in which the characteristic of microscopic and physicochemic identification of the sarcotesta of ginkgo biloba L were studied, the content of water and ash in the sarcotesta were determined as 10.98±0.4%, 3.55±0.5% respectively.2.The TLC, UV sepectrophotometry and HPLC methods were established for quantitative and qualitative determination of ginkgolic acids. On 60GFi54 silica gel plate, the effect of different mobile phase on Rf value of ginkgolic acids was studied, the results showed that the Rf value was suitable when use petroleum ether-aether-acetic acid(70:30:1,v/v) and petroleum ether -aether-formic acid (70:30:1,v/v), and the Rf values were 0.525 and 0.65 respectively. In UV sepectrophotometry, the analysis wavelength was 322nm and calibration curve was determined. It has high accuracy in quantitative determination of ginkgolic acids. The conditions of HPLC determination for gingkgolic acids are: column: Inertsil ODS-2 (250mm ×4.6mm, 5μm), mobile phase:MeOH-3%HAC(92:8, v/v), flow rate : 1.0mL-min-1, wavelength:3l0nm, column temperature: 40 .The ginkgolic acids were determined by using external standard method which had higher accuracy than UV sepectrophotometry.3.Two resins, D290 and S-8, were selected from 8 different resins according to their high adsorption capacity for ginkgolic acids and the capacity for ginkgolic acids were 148mg/g, 127.17mg/g respectively. Their static adsorption behaviours were studied and their adsorption isotherm and dynamic curves were got. The adsorption isotherms of the resins were simulate to Langmuir type adsorption. Their desorption processes were also studied. Ginkgolic acids adsorbed on the S-8 resin can be desorpted by petroleum ether, petroleum ether-ethyl acetate (90:10-80:20, v/v), the adsorption ability of S-8 for ginkgolic acids had no obvious decline after being used three times. Ginkgolic acids adsorbed on the D290 resin can be desorpted by petroleum ether- acetic acid (99:1, v/v) and it can got high desorption. In fix-bed adsorption process of S-8 resin, the effect of flow rate and concentration of ginkgolic acids on adsorption were studied and the results showed that adsorption operation was suitable at 13.54mg/mL and 5mL/min. The fix-bed desorption process was also studied, it was suitable when the desorbent flow rate was 1.8mL/min. Purified by S-8studied, it was suitable when the desorbent flow rate was 1.8mL/min. Purified by S-8 resin, the purity of ginkgolic acids was 85.59% and the recovery was 92.35%. Different purification methods for ginkgolic acids were compared, and the process of resin adsorption for ginkgolic acids purification was evaluated.4.Supercritical CO2 extraction of Ginkgolic acids in the sarcotesta of Ginkgol biloba L was studied. The single factor experiment showed that the extraction ratio improved as pressure increased between 20-30MPa, and improved as temperature increased when below 45℃ but decreased as temperature increased when higher than 45℃. The extraction process was completed in 6h. The conditions for the extraction were also studied by orthogonal experimental design based the content of ginkgolic acids in the extract, the optimum conditions for the yield of ginkg... |
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