The Experimental Study On Hydrogen Production Of Several Varieties Spirulina (Arthrospira)

Being a natural food and drug, Spirulina have been accepted by the people and proved in the practice. In the recent years, people have paid more and more attention on the exploitation and research of other functions. Especially since 1979, being biological energy, the study on Spirulina has gotten unique attention after recognizing it has the characteristic of releasing the hydrogen. In the 21st century, the reasons, such as energy crisis, environmental pollution, greenhouse effect & the ecological environmental destruction etc. made the exploitation and research of the biological energy more necessary than before and the research of Spirulina get more concern. Since Spirulina have not only has been treated as food and drugs, but also raw material of picking up other substance. In the same time, if people can collect and store the hydrogen released by Spirulina as useful hydrogen energy sources, Spirulina will be the most ideal clean ,renewable biological energy by now. So, the study on releasing the hydrogen of Spirulina has very important practice & applicative significance.Spirulina are a self-supportive, nucleus microorganism which has the photosynthesis ability, and releasing hydrogen is there own physiology phenomenon. The production of hydrogen is closely related with its growth & physiological process, which wholly finishes in the Spirulina cell. The growth relies on the cell photosynthesis, and the system of photosynthesis is made up of PSI (PhotosystemⅠ) & PSⅡ(PhotosystemⅡ) on the membrane of the thylakoid in the cell. PSⅡabsorbs the energy and decomposes water into electron under the sunlight,and takes up electron through electron acceptor,passes the electron to PSI electron acceptor & then ferredoxin by electron transmitting chain.When hydrogen enzyme gets the electronic from ferredoxin(Fd) by the way of the electron transmitting chain,it reduces the H ion into hydrogen to release, which is the way to produce hydrogen.So, releasing hydrogen of Spirulina is happened in the function of hydrogen enzyme,and connects tightly with it’s own physiological process. At present, the research on Spirulina is limited to the basic study. This study chooses 9 varieties (strains) of Spirulina, in which, according to the biology classification,8 belongs to Arthrospira,1 is Spirulina subsalsa which belongs to Spirulina genus. In the interior normal raising condition, the writer studied detailedly on the characteristic of releasing hydrogen, and enriched the experimental basic material about the study on the releasing hydrogen, which has important meaning both on the experiment skills and the mechanism discussion.In the way of meteorological chromatograph & OD560, the writer examined the hydrogen evolution capacity and the speed of growth of 9 kinds of Spirulina, further more, compared and analyzed the experiment result. In the interior normal raising condition, the writer chose to study the main surrounding influencial factors of the hydrogen evolution capacity and the speed of growth of Spirulina,such as the strength of illumination, the time of illumination, the raising temperature, the oscillation frequency & the vaccination quantity,and did a series of single factor experimental study on them. By analyzing the result of the experiment of oxygen evolution capacity and the speed of growth, the writer got that the hydrogen evolution capacity and the speed of growth of the 9 kinds of Spirulina (Arthrospira) each has different surrounding factor demand, and in another way, it showed the growth had different extensiveness to the surrounding. After choosing the most suitable raising surrounding each for 8 days to logarithmic phase, the writer checked the hydrogen evolution capacity and compared the oxygen evolution capacity in the dark growing surrounding. The result indicates that different kind shows different hydrogen evolution capacity,the orders are:No.9> No.8> No.4> No.1> No.7> No.2 > No.5> No.3> No.6. In the same time, the result also indicates different speed of growth,the orders are: :No.9> No.2> No.4> No.8> No.7> No.5> No.3> No.1> No.6.This shows that different Spirulina has different hydrogen evolution capacity and the speed of growth obviously.Further more, the hydrogen evolution capacity and the speed of growth are being positive correlation, but not corresponding correlation.In the way of orthogonal optimization design, the writer did a conditioned optimization experiment on the main influential surrounding factor to the hydrogen evolution capacity in the raising process, and got the most optimized combination of each hydrogen evolution condition and the main influential factor. It shows each Spirulina has its own optimized condition, and different kind displays differently on the level of influencing primary and secondary relations. Above all, we can get that the strength of illumination and the oscillation frequency are the main influential factors on the hydrogen evolution capacity. The reason is that the strength of illumination influences the photosynthesis most, then energy accumulation of photosynthesis, while the energy amount directly influences the level of hydrogen evolution capacity; while the oscillation frequency influences photosynthesis by ways of adjusting the density of the dissolved Oxygen in the nutrient fluid, and finally reach the aim of influencing the energy accumulation and the hydrogen evolution capacity.By analyzing the result of the optimized experiment among the hydrogen evolution capacity and each surrounding factor, the writer got the regression equation to do further analyze and calculate to get the quota relations and provided plenty experiment data for hydrogen evolution capacity of Spirulina.This essay gets that different kind of Spirulina has different hydrogen evolution capacity and amount by comparing 9 kinds of Spirulina, and the difference is apparent. Spirulina subsalsa has the biggest hydrogen evolution capacity, the activeness is 98nmol·mg-1drywt·h-1, the greatest difference is also showed on the speed, the highest is No.9 Spirulina subsalsa, then the second is No.2 platensis (Arthrospira). So it is important to study the kind choice of Spirulina to release hydrogen.This essay did a cell biology experiment on Spirulina in the way of observation method of light microscope & electron microscope.The writer got the micro structure drawing of the superficial appearance & the internal structure, and found the differences among different kinds by observing the external features and the ultrastructure of the Spirulina(Arthrospira) silk body. After combining with Spirulina releasing hydrogen & growth, the essay analyzed and compared different kinds of Spirulina, and discovered that the sort of Spirulina which growed fast and released more hydrogen had more thylakoid & Carboxysome etc. inside the cell, especially there were more Spirulina subsalsa which released the most amount of hydrogen than platensis(Arthrospira). This shows that the different contents of thylakoid & Carboxysome affect the photosynthesis efficiency, while the photosynthesis of Spirulina affects the growth speed & the efficiency of releasing hydrogen. Above all, the result shows the close relation between the Spirulina releasing hydrogen and the cell structure & physiology function.Through the experimental study on the releasing hydrogen of 9 Spirulina, the essay shows that different sorts don’t have the same content, which provides experimental data for choosing the Spirulina kinds and foundation for sifting. The determination to the superficial appearance & ultrastructure structure characteristic shows that different kinds has differences, which provides the basic material for doing further study on Spirulina study in the field of cell biological mechanism. It also has theoretic meaning to both studying the releasing hydrogen mechanism and photosynthesis mechanism, and their relationship from the level of moleculars.