Isolation, Culture And Biochemical Determination Research Of Fresh Water Algae

There are a large diversity in fresh water algae, which have a great grow rate and biomass, and these algae can be found in all over the world. Microalgae have numerous applications due to their original chemical composition such as proteins, lipids, carbohydrates, poly unsaturated fatty acids, amino acid, pigments and a wide array of compounds with biological activity including antibiotics, algicides and other toxins. The application researches have been reported focusing on aquaculture feeds, biodiesel, human foods, pharmaceuticals, cosmetics and materials. Recently, The primary studies of algae are biodiesel application and marine animal foods because of scarce oil energe and limids of aquaculture feeds. The other researches resources about algae application are marine algae, and the fresh algae's research are little, considering HUBEI is a area with lots of fresh water so our research separate ten species of algae in fresh water in HUBEI, and then study these ten purity algaes in below aspects:1. Identify these ten species and observe their growth behavior in determinate culture medium through their growth curve. The results indicate that eight species are green algae which are algae A Chlorella pyrenoidosa; algae B Selenastrum bibraianum; algae C Scenedesmus acutiformis; algae D Scenedesmus serratus; algae E Chlorella vulagris; algae F Chlorella ellipsoidea; algae G Quadrigula chodatii; algae H Chlorococcum hum cola and two species are diatom which are diatom a Fragilaria intermedia; diatom b Fragilaria capucina var.lanceolata. From the growth curve we can see the green algae are match to the SE culture and corresponding growth factors, but diatom are grow slowly with D1 culture. And then growth time is devided to four terms according to the rate of growth.2. Mensurate the content of protein, glucose, lipid and pigment of ten algae species in four terms. The results show that the contents of protein, glucose, lipid and pigment from ten algae species at four growth rates are 1.91%-18.58%, 5.02%-49.91%,2.86%-31.29% andl.383mg/L-9.567mg/L, respectively. Conpared with the nutritional value of ten algae species we chose the green algae A Chlorella pyrenoidosa, green algae B Selenastrum bibraianum, green algae F Chlorella ellipsoidea, green algae G Quadrigula chodatii, diatom a Fragilaria intermedia and diatom b Fragilaria capucina var.lanceolata for the best nutritional algae. Meanwhile, compared with lipid of ten algae species we conclude the diatom b Fragilaria capucina var.lanceolata was the potential biodiesel resource.3. Detected the contents of fatty acids from ten algae species at four growth rates and the results show that the primary constitute of fatty acid in green algae was poly unsaturated fatty acid, but the primary constitute of fatty acid in diatom was monounsaturated amino acid. That is maybe for sure that algae B, algae F, algae G, diatom a and diatom b can be feed for aquaculture at the forth grow term, algae H can be feed for aquaculture at the third grow term comparing the contents of fatty acid, protein, carbohydrate, lipid and pigment from ten algae species at four growth rate.4. Detect the mineral-element composition of six best selected algae species, and the result show that the contents of elment Mg, Fe, Mn, K, Ca, Zn, Cu, Ni, Pb range from 5.678～19.08mg/g,2.760～10.81mg/g,2.038～7.784mg/g,11.16～38.17mg/g, 1.590～7.161 mg/g,0.1186～1.408 mg/g,0.2522～1.525 mg/g,0.0024～0.025 mg/g, 0.004～0.008mg/g, respectively. The contents of Cr and Cd are not detected. All algae species are rich in Mineral-element composition such as Mg, Fe, Ca, Mn, K and the algae contain the maximum ordinary elements and trace elements are green algae F and green algae H.According to the research above the algae of Selenastrum bibraianum, Chlorella vulagris, Quadrigula chodatii, Chlorococcum humcola, Fragilaria intermedia and Fragilaria capucina var.lanceolata can be considered to used in fish farming, and then continue to follow application of in vivo feeding experiment, and get a higher nutritional value of aquatic algae to alleviate the shortage of animal feed varieties; at the same time, by means of changing culture ways and culture circumsentence or molecular biology techniques to improve its lipid content again refer to the high lipid content algae of Fragilaria capucina var.lanceolata, and through a series of experiments of lipid extraction, sapolification and esterfication to produce a high yield of biodiesel.