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Studies On The Extraction Of Chlorogenic Acid And Caffeic Acid From Oiled-type Sunflower And Their Protective Effects On The OxLDL-induced Damage To Endothelial Cells

Posted on:2004-06-30Degree:DoctorType:Dissertation
Country:ChinaCandidate:S Z ChenFull Text:PDF
GTID:1101360092996384Subject:Agricultural Products Processing and Storage
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Oil-typed sunflower is rich in phenolic acids, including chlorogenic acid (CGA) and caffeic acid (CA). Recently, studies have indicated that CGA and CA may be biologically active in antioxidant, preventing free radical damage and inhibiting cancer growth. There is no report on the research and utilization of CGA and CA in oiled-type sunflower meal in China. The objective of this paper is to study the analysis, extraction, separation, purification of CGA and CA from oiled-type sunflower meal and their protective effects of CGA and CA on the oxidized low density lipoprotein (oxLDL) induceddamage to ECV-304 endothelial cells. The major results are shown as follows.A reverse-phase high performance liquid chromatography (RP-HPLC) method was developed for determination of CGA and CA in sunflower kernels and hulls. Chromatographic separation was performed in ALLTIMA Cjgcolumn (250mmX4.6mm ID; Sum) using a acetonitrile -2% glacical acetic acid (15: 85, v/v) mixture as the mobile phase at 1 .OmL/min flow rate. They were detected with SPD-6AV ultraviolet detector at 327 nm. CGA and CA were eluted in 18min with satisfactory separation. Relative standard deviation of 1.25% ~ 1.46% and average recovery of 89.22%~95.29% for the method have been found. The method is rapid, accurate and repeatable. The content of CGA and CA of four typical oiled-type and confectionery varieties of sunflower were determined.Different methods of extracting CGA and CA from oiled-type sunflower were studied. (1) Water soaking. Single element test and Lg (34) orthogonal design test were done about soaking temperature, soaking time, soaking frequency and the ratio of solid-to-liquid. The result shows that extraction rates of CGA and CA are high at 60℃, 1.5h, 2 times and 1:30. (2 ) Methanol solution soaking. Single element test and orthogonal design test were done about the content of methanol, soaking time, the ratio of solid-to-liquid and soaking frequency. The result shows that technological parameter of extraction rates of CGA and CA was appropriate when soaking solutions contain 70% methanol, at 60℃, 1.5h, 2 times and 1:30.(3) Supercritical fluid carbon dioxide extraction. The effects of ethanol concentration, pressure, temperature on the extraction rates of CGA and CA was discussed with three factors and second power rotation regression mathematical model. Extraction temperature, pressure and ethanol concentration have a very significant effect (a =0.01) on the extraction rate of CGA. The interaction between pressure and ethanol concentration has a significant effect ( a =0.05) on the extracting rate of CGA, But not the extraction temperature alone. The suitable SFE-CO2 parameters for CGA are ethanol concentration 15%, the extraction pressure 63.94MPa, the extraction temperature 72℃ and the extracting 3.0 hours, then the extracting rate will be 44.14% in terms of theory. The extracting rate of ethanol solution is the highest among three methods of extracting, the next is water solution, the method of supercritical fluid carbon dioxide extraction is the lowest to extract CGA from sunflower meal.The separation of CGA and CA by using the method of macroporous adsorption resin was experienced. The result indicated that AB-8 Of week polarity macroporous resin fits for the separation of CGA and CA. The condition of adsorptive and desertion is appropriate to elute with 4BV, 2BV/h andpH4.5 water solution, then desorpted with 5BV, IBV/h and 70% ethanol, CGA and CA can be separated effectively, the desorptive rate is 75.02% and 79.78% respectively.Isolation and purification of CGA and CA from oiled-type sunflower meal using high-speed countercurrent chromatography (HSCCC) on a preparative scale were demonstrated. Solvent systems, rotation frequency, concentration of sample solution and retention value of station phase were discussed. The result showed the separation was run at a revolution speed of 1000 rpm, Flow rate was set at 1.5mL/min and concentration of sample solution is 30mg/mL with appropriate solvent system (hexane/ethyl...
Keywords/Search Tags:Oiled-type sunflower, Chlorogenic acid, Caffeic acid, Extraction, Oxidized low density lipoprotein, ECV-304 endothelial cells
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