| Algae bloom were usually to cause the eutrophication of local water bodies, but algae are important for the stability of the biological self-purification of water system. There were 120 800 hectares of marine aquaculture area and the annual output was about 25 700 tons. Chinese algae are resourceful which have huge development advantage and latent capacity. But the development of algae products is very limited which were as food and industrial raw materials with low price to market. The phycobiliproteins are a family of water soluable and stable fluorescent proteins. It can catch the sunlight of 450~660 nm visible light. It has been not only widely used in foods, cosmetics, medicine and health and fluorescent fields. But the processes for the recovery of phycobiliprotein have lots of stages and low recovery, which make the phycobiliproteins too expensive to apply in all fields. In view of this, the major research objective is to establish an efficient, simple, environmental and commercial downstream process in industry to recovery phycobiliprotein of high purity and high recovery. And try to apply the phycobiliprotein as environmental function-materials sensitizing agent in dye sensitized solar cell. The purity is the ratio of the absorption of phycobiliprotein and total protein. It is an important technique data for the extraction of phycobiliproteins. The main research contents and results are listed as follows.To establish the needles-plate corona discharge technology to break the algae cell with the principle of the plasma discharge. The purity of C-PC was 0.46 with the output voltage of 8 k V and the breaking time was only 1 min. The purity of R-PE was 0.56 with the output voltage of 8 k V and the breaking time of was 5 min. It is successful in collapsing the external structure of the algae cells by irreversible electroporation in the cytoderm. The holes and pores radius observed with scanning electron microscope. It was one kind scaling up technology of breaking cellulase that was more celerity, effective, simple, economic, clean green than other means.In order to recover the phycobiliprotein, the adsorbent and flocculation were used to adsorb and flocculate the other protein. The acticarbon was the best adsorbent. The purities of C-PC and R-PE were 0.71 and 1.03 with the acticarbon doses of 20 g/L and 35 g/L. The purity was more than the food grade. The purity was increasing by the adsorbent, but it might be adsorb the phycobiliprotein to decreasing recovery rate.The phycobiliprotein was recovered and purified by the gradient of salting process. The optimization was proved the third-step saturation of ammonium sulfate that purity of C-PC was 1.29 with the recovery rate of 71.77%. The first-step saturation was best to recover R-PE with the purity of 1.13 with the recovery rate of 84.89%. The purity of CPC and R-PE was more than the food grade.It was to establish the best aqueous two-phase systems to extract and purify C-PC and R-PE from the dry spirulina platensis and porphyra haitanensis efficiently. The comparison of the influences of various system parameters was to establish a systematic approach to achieve optimal parameters of ATPS. The optimal conditions to extract and purify C-PC were proved in polyethylene glycol(PEG) 1000 and sodium phosphate, system p H of 5.80, the tie-line length(TLL) of 28.50%(w/w), the volume ratio(Vr) of 0.16 and the water content of 77.78% to increase the purity from the initial purity of 0.46 to 1.33 after the first extraction. The phase separation time was 10 min and the recovery rate was 89.52%. The purification factor was 5.01 after the third ATPS. The optimal conditions to extract and purify R-PE were proved in PEG1500 and potassium sodium tartrate, system p H of 8.06, the TLL of 22.30%(w/w), the Vr of 0.12 and the water content of 74.26% to increase the purity from the initial purity of 0.47 to 1.47 after the first extraction. The phase separation time was 12 min and the recovery rate was 84.42%. After the second ATPS extraction the purification factor was 3.60. The optimal ATPS of C-PC and R-PE was the process of celerity, effective, simple, economic, clean green and scaling up.The phycobiliprotein was recovered and purified from 3 different blue algae and 4 different red algae in the environment using the established optimal purification processes. The purity of C-PC was the highest value of 3.42 from fresh spirulina platensis by the new processes. The purity was more than the pharmaceutical grade. The recovery rate was 89.17%. The purity of R-PE was the highest value of 3.07 from fresh Gracilaria lemaneiformis by the new processes. It was more than the pharmaceutical grade. The recovery rate was 79.05%. The purity of R-PE was more than 2.0 which were recoved from the porphyra haitanensis and porphyra yezoensis with the recovery rate over 70%. Therefore, they were the better materials to revovery the R-PE. The dry algae powders were safer and favorable to scaling up and applying in industry and the purity was not less than that from the fresh algae. The all optimal processes were celerity, effective, simple, economic, clean green and scaling up.The electrode of the phycobiliprotein as sensitizing agent in dye sensitized solar cell with Ti O2 can absorb the sunlight of visible light. And the R-PE did not disturb the electrode to absorb the ultraviolet. The R-PE sensitized Ti O2 electrode can generate photocurrent by applying a certain bias voltage. But the monochromatic incident photon-to-electron conversion was low. Natural light harvesting proteins as dye sensitized cells are more clean and environmental. |
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