Effects Of Hormone-Like Substance On The Culture Of Chlorella

As a high photosynthetic efficiency of species, microalgae are placed increasingly high expectations in the fields including renewable energy, global warming mitigation, food, and health care. However, there have many problems in large-scale microalgae cultivation, and causing a low productivity, a long payback period and the costs of microalgae cultivation hovering at a high level. These are all reasons for the slow development of microalgae industry. Many scholars have made a lot of work and research in many way such as the process of CO2 complementary and the design of nutrients composition, and they have achieved many achievements. For the harvesting costs and many other considerations, high-density microalgae cultivation technology is more reasonable. This study based on the premise of high-density microalgae cultivation, and studied the effects of several hormone-like substance on the growth of Chlorella by univariate experiments, with which has been widely applied in agricultural production.In conditions of each plant hormone-like substance initial concentrations not higher than 20 ppm, they all have effects on the growth and metabolism, as well as changes in intracellular material composition with their different characteristics. CPPU for the growth of Chlorella is promoting the absorption of nutrients, promoting cell division and elongation. For the content of intracellular components had no significant effect. The initial concentration of 5 ppm is considered to be the most economical and reasonable. The effect of DA-6 is throughout the whole process of cell growth and cell metabolism for Chlorella. Also a tremendous impact has been found to the content of intracellular lipid. The initial concentration of 2 ppm has the most advantageous for the accumulation of lipid. The initial concentration of 2,4-D within 20 ppm are possible for the cultivation of Chlorella. And we get the largest rate of biomass accumulation when the initial concentrations at 10 ppm. 2,4-D and IAA are more suitable for getting the intracellular polysaccharides and intracellular proteins.6-BA and a higher concentration of DA-6 are more suitable for the promotion of intracellular lipid accumulation in Chlorella cultivation.Then we paid attention to the changes of intracellular fatty acid composition with the conditions of different initial concentrations. Effects of the plant hormone-like substances on fatty acid composition are different form that on the growth and metabolism. Several substances did not change the overall structure of the fatty acid composition. The initial concentration of 10 ppm 6-BA and 2,4-D can improve the palmitic acid and oleic acid in the total fatty acid in proportion, but at the expense of linoleic acid. DA-6 is significantly increased the accumulation efficiency of linoleic acid, not only increased its share of the total fatty acids, but also improve the cell yield at the same time. All of this confirmed that several plant hormone-like substances have their characteristics on Chlorella cultivation.By the brief analysis on the economic benefit, we can see that the use of plant hormone-like substances are reasonable, and has certain actual application value and future.