Extraction And Purification Of Fucoxanthin And Fucoidan From Undaria Pinnatifida

Undaria pinnatifida belongs to Alariaceae of Phaeophyta, which has good nutrition and can be used as food and medicine. Undaria pinnatifida is a characteristic algae of China and has abundant resources. Fucoxanthin belongs to carotenoids oil soluble pigment, while fucoidan is a kind of sulfated-polysaccharide containing fucose. They all have various biological activities. However, at present the mainly development and utilization of Undaria pinnatifida still focus on some nutrition materials, such as protein, fiber, etc. The studies of fucoxanthin and fucoidan are rare.The objective of this dissertation is to study the extraction and purification of fucoxanthin and fucoidan from Undaria pinnatifida. and the process of arsenic removal. The main results are as follows.HPLC testing methods of fucoxanthin and fucose in fucoidan are established. According to chromatographic resolution, standard curves, reproducibility, repeatability, recovery test, etc. the analytical results show that all these methods are simple and reliable. They could be used in the quality control of fucoxanthin and fucoidan products in domestic and international markets.The optimal parameters of the extraction of fucoxanthin from Undaria pinnatifida were obtained through analyzing the extraction time, ratio of material to liquid, temperature and other factors on fucoxanthin extraction. The experimental results show that,12times95%acetone,2.5hours,55℃, extracting for3times, should be more efficient and economic. The purity of fucoxanthin could be improved from2.31%to more than24.2%after silica gel column purification.The optimal parameters of the extraction of fucoidan from Undaria pinnatifida were obtained through analyzing the extraction time, ratio of material to liquid, temperature and other factors on fucoxanthin extraction. The experimental results show that,10times pH2.0water.2.5hours,95℃, extracting for3times, should be more efficient and economic. In order to make purer fucoidan, enzymatic dissociation as de-protein method, AB-8macro-porous resin as decolorant, and DEAE-cellulose chromatography as further purification process were used.Compared several (citric acid) water soaking experiments to remove arsenic, pH3.0citric acid soaking for three times,3hours every time should be more effective. The experimental results show that, arsenic content in raw Undaria pinnatifida has dropped from128.6ppm to9.2ppm,92.8%arsenic has been removed. The process is high effective and simple.LSA-AS chelated resin could be used as further arsenic removal agent. The result shows that LSA-AS chelated resin could decrease arsenic in fucoxanthin solution from6.8ppm to0.7ppm,89.7%removal rate, while reduce arsenic in fucoidan solution from7.3ppm to0.9ppm.87.7%removal rate. In order to better remove arsenic in extraction and purification process, citric acid water soaking as raw material pretreatment and LSA-AS chelated resin as further treatment methods have been confirmed economically and effectively.Considering all these factors, an optimized process has been proposed. After clearing salted Undaria pinnatifida, pH3.0citric acid water soaking for10hours, then10times pH2.0water,2.5hours,95℃, extracting for3times, collect filtrate and filter residue separately. The filtrate was enzymatically dissociated as de-protein method, AB-8macro-porous resin as decolorant, LSA-AS chelated resin as de-arsenic, and DEAE-cellulose chromatography as fucoidan further purification process. The filter residue was extracted by12times95%acetone,2.5hours,55℃, extracting for3times, LSA-AS chelated resin, and column chromatography of silica gel as fucoxanthin further purification process.As an ultimate route,100grams of dry Undaria pinnatifida can obtain0.30g fucoxanthin product with24.6%fucoxanthin content and0.7ppm arsenic, and4.48g fucoidan product with87.5%fucoidan,18.9%organic sulfate,20.7%fucose,2.9%protein, and0.9ppm arsenic.