Effects of Salinity on the Growth and Biochemical Properties of a Freshwater Algae Scenedesmus sp.

doi:10.13560/j.cnki.biotech.bull.1985.2016-1159

Abstract

Abstract: The aims of this work are to analyze and compare the effects of different salt concentration（0-40‰）on the growth and biochemical characteristics of a freshwater algae Scenedesmus sp. incubated in small tubular bioreactors，and evaluate the industrialization potential of culturing this algae in seawater as well explore the adaptive mechanism at high salinity，which provides theoretical references for further study on seawater domestication. The growth of the microalgae，the content of protein，lipid and polysaccharide，and the composition of pigments and fatty acids were analyzed correspondingly by microscopic observation，Soxhlet extraction，Kjeldahl method，phenol sulfuric acid determination，gas chromatography technology，and HPLC. The results showed that cells grew bigger and naturally precipitated at high salinity，meaning that it can be harvested at low cost. The study also found that growth of Scenedesmus sp. was gradually inhibited with the increase of salinity，and completely inhibited at the salinity of 40‰；however，it still grew well at the salinity of 30‰ with biomass of 2.84 g/L，and higher protein content（95.40% higher than 0‰ group）with similar protein productivity as that by freshwater. Combined with the great cost reduction of producing protein at high salinity，culturing Scenedesmus sp. in seawater for protein resource is of high potential. Moreover，with the increase of salinity，Scenedesmus sp. tended to accumulate more β-carotene，astaxanthin，and even soluble sugar，which might be the key physiological basis of adapting salt-stress.

Key words: freshwater microalgae, Scenedesmus sp., high-salinity stress, growth, biochemical composition

LI Jia-ying,LI Tao, TAN Li,WU Jia-yi ,XIANG Wen-zhou, LIU De-hai. Effects of Salinity on the Growth and Biochemical Properties of a Freshwater Algae Scenedesmus sp.[J]. Biotechnology Bulletin, 2017, 33(7): 155-161.

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