| Grape seed is a good resource for the oil and proanthocyanidins. It was reported that the grape seed oil could be used for health care due to 76% linoleic acid in it. Also, the oil content in the grape seed is relatively high with number of 13%~15%. However, the grape seed is also a good resource for proanthocyanidins. The oligomers, including dimmers, trimers, and tetramers, are of very strong anti-oxidative activity. They could be used for preventing and curing more than 80 radical-deduced diseases in humans including atherosclerosis, arthritis, etc. Nowadays, proanthocyanidins has been widely used in the field of medicine, cosmetic and functional food. However, in China, the theoretic research and the development of new products are far behind other courtries. Our products are of relatively poor quality with characters of less quality stability, less anti-oxidative activity, thus relative low prices. So our purpose in this study emphasis on working out an integrated techniques to produce products with high content oligmers in a reasonable, economic and efficient way. Some of the conclusions are as follows:1. Extracting grape seed by Supercritical Fluid Extraction. According to previous study, the effect of temperature, pressure, duration and the moisture on the extraction rate of grape seed oil were studied. The results showed that the high extraction rate could be obtained with parameters of pressure 30MPa, temperature 45 °C, extracting 90 min, and water moisture 6%.2. The pilot study on extracting OPC's while the ethanol or methanol as contrainer showed that it was possible to increase the contents of catechin and low molecular weight phenols in the product. And the ethanol had better effect in doing so than the methanol. By further HPLC-MS analysis, the catechin, epicatehin, as well as two dimmers were determined. It indicated that it's possible to extract these functional compounds by SFE. However, because of the complex structures of proanthocyanidins, the total extraction rate is quite low.3. Extracting proanthocyanidins by solvents was studied. Orthogonal test indicated that the optimun comditions were as follows: extracting proanthocyanidins with 80% ethanol at pH 5.0, temperature 60°C for 90min, the ratio of solvent and grape seeds 6:1, sample is extracted 3 times. Extracting under these parameters, the extraction rate and purity of proanthocyanidins were16.7% and 58.3% respectively.4. HPD600 and HPD450, were selected among six macroporous adsorbance resins according to static adsorption and disadsorption. At the same time, the balanced velocity constants of 6 microporous resins were calculated. The results indicated that single layer adsorption was the major link between resins and proanthocyanidins. Further testing in column chromatography indicated that the HPD600 is the best one. The best seperation and purification could be obtained while the sample loading and eluting flow rate are 0.60mL/min and 0.38mL/min respectively. Under these conditions, the adsorption rate and disadsorption rate were 60% and 97.7% respectively. The purity reached at 95%. TLC analysis showed that the product is a mixture of momomers, oligomers, and polymers.5. Polyamide column chromatography is an useful method to seperation and purification chemicals with principle of hydrogen bond adsorption. The suitable conditions were loading up with 0.45mL/min crude grape seed extract in which the proanthocyanidins was 5-8 rag/mL. Eluting with 80% acetone was of much higher disadsorption rate than those of others. The purity of product is about 92%. The results of grade eluting indicated that most of proanthocyanidins was eluted off by 60% acetone solution with 76.6% disadsorption rate. The proanthocyanidins had not been eluted off by 20% acetone solution.6. The capacity of eliminating OH ? (calculated as IC50) in chemical luminescence testing were determined. The results showed that the capacity of eliminating OH ? of crude grape seed extract was better than that of catechin and of a kind of market product. Among those fractions from grading slution, the capacity of eliminating OH ? of fraction 80% and fraction 40% was three times more than that of catechin.7. Further quantity analysis on fraction 20% and 40% by HPLC-MS was studied. Catechin, epicatechin, and tow dimmers were determined in the fraction of 20% acetone, while, four dimmers were determined too in the fraction of 40% acetone.8. The mean molecular weight, as well as the mean degee of polymerization, of fractions from grading elution were determined by improved gel permeation chromatography with acetone and 8M urea as mobile phases. The mean molecular weight were 1419,1881 and 2594 respectively. And the mean degee of polymerization were 5.5,6.5 and 9.0.9. The stability of proanthocyanidins was studied in the simulate systems in food industry. The results showed that proanthocyanidins were likely stable at low temperature and low pH. Among different mineral ions, Sn2+, Fe2+ and Cu2+ have significant influence on the stability of proanthocyanidins. The amount would decrease under the sunlight. Vc and NaHSCh could improve the stability of proanthocyanidins, and their effects were related to their concentrations. Furthermore, proanthocyanidins present different colors at different pHs.10. For improving the stability of proanthocyaidins, the encapsulation technique was applied in this study. Several wall materials, including glutin, Arabic gum, 3 -dextrin, microporous starch, malt dextrin and isolated soya protein, were selected in this work. The results indicated that micro-porous starch and P -CD were not good choices for encapsulating grape seed extract. It was above 80% microencapsulating efficiency when encapsulated with malt-dextrin and bean isolated protein. In this part, the best encapsules could be obtained at the parameters as follows: the ratio of core material and wall material was 6:94, coming-in temperature is 210°C, coming-out temperature is 67 °C. The ratio of core material and wall material was the most important factor. The coming-in temperature was the minor importance. Coming-out temperature had less influence on encapsulating proanthocyanidins. From the electric microscope photos, the encapsulation envelope with malt dextrin and isolated soya protein was round or ellipse,with average sizes at around 50 u m.
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