Research On The Interplays Of The Concentrations Of Carbohydrate And The Chemical Compositions Of Medium In Freshwaster Algae System

Algae are among the oldest lifeforms on earth. They convert sunlight and carbon dioxide to carbohydrates. During their growth process, algae secrete polysaccharides. There must be some relativity between the environment factors and the content of polysaccharides. In this document, phenol-sulfuric acid associated with caramelizing-grating photometer method is used to determine the content of polysaccharides in algae solution. The relativity is studied by measure the contents of polysaccharide and relative chemistry factors.The result shows that the total nitrogen, TN, and the total phosphorus, TP, in water are the restricting factors on the secreting of polysaccharide. When the contents of TN and TP are within the range of (1.1 to 8.44) mg/L and (0.09 to 0.17) mg/L respectively, the content of polysaccharide will increase. The role of phosphate enzyme, PE, is to keep the content of TP within this range. Another secretion, protein, will also increase with polysaccharide during the growth process of algae. But while the level of nourishment can not satisfy the need of growth, both contents will reduce. Then algae will secrete protein enzyme, which can decompose protein to increase the nourishment level. Although the sunlight plays an important role in the polysaccharide converting, its effect on the secreting of extracellular polysaccharide is unimportant. The active oxygen is the most important factor on the secreting because the purpose of secreting is to reduce the damage of active oxygen. In summary, our result reveals that it is possible to use the content of polysaccharides to evaluate the level of supernutrition in freshwater.