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Study On Key Factors Of Production And Processing Of Spirulina Platensis From The Alkali Lake In Ordos Plateau

Posted on:2016-09-28Degree:DoctorType:Dissertation
Country:ChinaCandidate:Z Z WangFull Text:PDF
GTID:1220330464463744Subject:Conservation and Utilization of Wild Fauna and Flora
Abstract/Summary:PDF Full Text Request
There are many serious problems in many respects such as antiquated medium formulation, serious waste of resources, the rough process of harvest and Phycocyanin extraction, the more content of ash and As and uncultured methods saving Spirulina species, which severely restrict the development of Spirulina industry in Etuoke Qi region though it is the main Spirulina region owning advantage in China. The technical parameters of the nutrient utilization, arsenic enrichment, cleaning, removing water and drying in the harvesting process, extracting Phycocyanin, the Spirulina platensis morphology at low temperatures and preservation methods were studied, in order to establish the key technology system suitable for this area for the production, processing and preservation of Spirulina platensis to provide technical reference and theoretical basis for high-yield, efficient, high-quality production of Spirulina platensis. The main conclusions are as follows:1. Under the same culturing conditions in Etuoke Qi, the results of single factor experiment and orthogonal experiment showed the optimum culturing consentration of NaHCO3,NaNO3, H3PO4,KCl, MgSO4·7H2O、FeSO4·7H2O to Spirulina platensis from Ordos were 6.3 g/L,1.0 g/L,0.06 g/L,0.5 g/L,0.1 g/L、0.007 g/L respectively, while 2.1 g/L,1.5 g/L,0.12 g/L,0.5 g/L,0.1 g/L、0.007 g/L for the introduced species. The average supplemented consentration of NaHCO3、NaNO3、 H3PO4、KCl、MgSO4·7H2O、 FeSO4·7H2O were 0.6 g/L,0.06 g/L,0.01 g/L,0.04 g/L,0.015 g/L、0.002 g/L to culture Spirulina platensis from Ordos after harvested for each time, while 0.4 g/L,0.04 g/L, 0.007 g/L,0.03 g/L,0.01 g/L、0.0015 g/L for the introduced species. The growth and yield of Spirulina platensis from Ordos were better than the introduced species. The growth of Spirulina platensis from Ordos was promoted obviously by fertilizing with 0.05 g/L NaNO3 and 0.02 g/L CO(NH2)2 or 0.08 g/L of NH4HCO3 per day. Yield of Spirulina platensis increased, the production cost reduced and trace elements and materials were saved by circularly using groundwater in closed culturing facilities. The growth of Spirulina platensis was not affected when without Ca2+, A5 and B6 liquid. The concentration of NaCl and Na2CO3 were higher than 10 g/L and 20 g/L could inhibit the growth of Spirulina platensis, so the culture medium should be replaced partially or completely.2. Arsenic content in the culture medium was came from the groundwater, NaHCO3 and NaNO3, and the percentage rate was 72% and 26% respectively. The arsenic content could be correspondingly kept in a stable state in each period of the cultivation. The arsenic content was reduced by cleaning with distilled water. The growth and production of two species were not inhibited when the arsenic in the culture medium was lower than 0.32 mg/L; the production of Spirulina platensis from Ordos was higher than that of introduced species, arsenic content of Spirulina powder of Ordos’s was obviously lower than that of introduced species under different arsenic concentratio.The arsenic content of the culture medium was positive correlation with the arsenic content of the Spirulina powder. Single-celled Spirulina platensis was induced mutation by radiation, then cultured in the nutrient solution of different arsenic concentrations, two strains of Spirulina platensis were selected which not only grew fast, but also remain the lowest content.3. Ash content of Spirulina powder was no more than 7% by cleaning with distilled water or acid soaked (0.00001 mol/L HCl or 0.0001% H3PO4) then washed with groundwater. The content of Carotenoids and Chlorophyll a and SOD activity decreased with the extension of exposure time at room temperature. Spirulina mud should be dried as soon as possible or placed in cold storage equipment promptly to make the loss of the content of Carotenoids and Chlorophyll a and SOD activity of Spirulina platensis slow down. The more effective way to dry Spirulina making the content of Carotenoids, Chlorophyll a and protein and SOD activity, the larger was spray drying rather than drying under sunlight or oven drying.4. The optimum concentration of (NH4)2SO4 was 40%-50% for protein extraction of Phycocyanin and decrease the extraction cost. The Phycocyanin purity of Spirulina platensis from Ordos was 1.67 times of the imported species, extraction rate was close for two species.The purity of Phycocyanin for Spirulina platensis from Ordos was significantly more sensitive to temperature than the introduced species; the working temperature controlled less than 55 ℃, the higher Phycocyanin activity could be maintained; pH value had significant influence to the Phycocyanin purity, the value of Phycocyanin purity was highest when pH value in 5-6.5. Spirulina platensis from the natural alkali lake in the Ordos plateau can withstand the cold winter with the vegetative form or its short broken segment under the low temperature. Spirulina platensis from Ordos can well survived under 5℃ and weak light conditio.
Keywords/Search Tags:Spirulina platensis, Nutrient utilization, As absorption, Harvest, Phycocyanin extraction, Overwintering form and preservation methods
PDF Full Text Request
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