Studies On The Isolation, Identification, And Antitumor Bioactivities Of Fucoxanthin In Algae

Fucoxanthin, an important kind of carotenoid which exists in the algae, shows biological activities such as antiobesity, blood glucose regulating, antitumor, radical scavenging, antioxidant, antiangiogenic activities and so on. It plays an important role on the human health, poultry and fisheries. Resources of algae are plentiful in China. Fucoxanthin, a major carotenoid which exists in the Phaeophyta and Bacillariophyceae, is an excellent health food supplement, additive and a potent drug candidate for cancer prevention. In this study, the Phaeophyta and its processing product and Bacillariophyceae are the experimental materials. We established the isolation and HPLC analysis method of fucoxanthin. which is simple, convenient and effective. It provides important scientific support for the research on fucoxanthin in the future. And the HPLC method to determine fucoxanthin contents in the algae was established. At the last, we studied on the anticancer effects of fucoxanthin extracted from the Undaria pinnatifida in vitro. They would accelerate the exploration of novel applications to fucoxanthin in food and drug fields. The main researches in this thesis are listed below:Effective and simple isolation methods for fucoxanthin in the Phaeophyta and Bacillariophyceae were established in this thesis. We did the structural identification on the fucoxanthin isolated through the silica gel column chromatography. And the purity of the fucoxanthin isolated is up to around 90%.Two different kinds of chromatographic conditions are established based on the different complexity of total pigments extracted from Phaeophyta and Bacillariophyceae. Both of them are great to detect the characteristic peak of fucoxanthin, which retention time is around at 9.5min. The HPLC method to determine fucoxanthin contents in the algae was established. This method is accurate and the linear relationship is good. So it could be applied to determination of the fucoxanthin content of a variety of algae and food, and help to establish the quality standards of fucoxanthin products.The antitumor activities of the fucoxanthin isolated from the Undaria pinnatifida were studied preparatory. We used MTT method on the fucoxanthin to have a cell-based assay and picked HepG2 cell to study its antitumor activity and discuss the possible mechanism by observing the cellular construction and AO/EB dyeing. And then, we discussed the influence of fucoxanthin systemically on the ability of HepG2 cell migration, adhesion, and invasion by wound assy, cells adherent assay, and transwell assay. Also, we studied on the antiangiogenic activities of fucoxanthin by the eanaliculization assay of ECV304 and CAM assay. All in all, we proved that fucoxanthin could control the proliferation, metastasis, invasion, and angiogenesis of tumor cell.This thesis made a systemic study on the isolation, identification, HPLC determination, and antitumor bioactivities of fucoxanthin in algae for the first time domestically. The researches would provide some academic and scientific groundwork for the exploration of novel applications to fucoxanthin in food and drug fields.