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dc.contributor.advisorÜlkü, Ayşe Semraen
dc.contributor.authorAltıok, Evrenen
dc.date.accessioned2014-07-22T13:52:14Z
dc.date.available2014-07-22T13:52:14Z
dc.date.issued2003en
dc.identifier.urihttp://hdl.handle.net/11147/3732
dc.descriptionThesis (Master)--Izmir Institute of Technology, Biotechnology, Izmir, 2003en
dc.descriptionIncludes bibliographical references (leaves: 56-61)en
dc.descriptionText in English;Abstract: Turkish and Englishen
dc.descriptionx, 79 leavesen
dc.description.abstractProanthocyanidin is a potent antioxidant that is why it directly affects many important diseases such as coronary heart disease, cholesterol etc. Thus, proanthocyanidin is one of the important dietary supplements, which is mainly found in grape seeds. In this study the extraction of this valuable antioxidant from grape seeds was studied. For the extraction of proanthocyanidins, different solvents such as ethanol, methanol, acetone and their aqueous forms were used. The maximum extraction yield was achieved after 24 h at room temperature. It was observed that 70% aqueous acetone was the best solvent with the highest yield of 17.5%. Yield of proanthocyanidin extracted with 70% aqueous acetone was 3 times greater than proanthocyanidins extracted with other solvents. The extract was freeze dried to obtain the product as powdered form. To compare the product with commercial ones HPLC chromatograms and FTIR spectra were taken and similar spectra were obtained. With HPLC, monomers of proanthocyanidins; (+)-catechin and (-)- epicatechin were determined. (+)-catechin was observed at 17.2 min as 3.06%w/w. Also, (-)-epicatechin was observed at 42.8 min as 1.99%w/w. Most of the drying methods are performed at high temperatures which may result negative effects on proanthocyanidin`s antioxidant capacity. Even the applications at low temperatures in case of freeze-drying have some disadvantages e.g. the process takes a long time, it is expensive and has some difficulties. Therefore as an alternative to other concentration and drying techniques, adsorption process was thought to be a promising technique. Although adsorption of proanthocyanidins on zeolites were not obtained, removal of excess water from the extracts can be achieved by using zeolites. This would possess as a promising technique for the concentration of the end productThe antioxidant capacities of proanthocyanidins from the grape seed extracts were also determined. Proanthocyanidin has an antioxidant capacity with 57 TEAC value, which is more than synthetic antioxidants; BHT, BHA, TBHQ and PG, 6.66, 0.593, 1.168 and 12.62 TEAC respectively. .en
dc.language.isoengen
dc.publisherIzmir Institute of Technologyen
dc.rightsinfo:eu-repo/semantics/openAccessen_US
dc.subject.lccTP159.A5 A45 2003en
dc.subject.lcshAntioxidantsen
dc.subject.lcshGrapes--Seedsen
dc.subject.lcshFlovanoidsen
dc.subject.lcshFouries transform infrared spectroscopyen
dc.subject.lcshHigh performance liquid chromatographyen
dc.titleProduction of proanthocyanidins from grape seeden
dc.typemasterThesisen
dc.contributor.authorIDTR30152
dc.contributor.departmentIzmir Institute of Technology. Biotechnology and Bioengineeringen
dc.relation.publicationcategoryTezen_US


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