2017 Volume 23 Issue 6 Pages 819-826
Microalgae are not only potential feed stock of biodiesel, but also an important source of high biological value products. Polysaccharide, as a family member of microalgae, has several important biological activities. In this paper, the culture conditions were optimized by response surface methodology for the production of intracellular water-soluble polysaccharide (IWSP). The highest IWSP yield of 88.1013 mg/L was obtained with the culture condition of NaNO3 362.5 mg/L, NaCl 85.4 mg/L and NaHCO3 2.4925 g/L. Gravimetric analysis revealed a total lipid content of 27.56% in this culture. IWSP was composed of mannose, xylose, galactose and glucose. The fatty acid of lipid was rich in unsaturated fatty acids contributed 55.38%; the main saturated fatty acids were C16:0, which counted for 41.98%. The antimicrobial activity of IWSP showed that antibacterial activity is higher than antifungal activity. It showed the highest antibacterial activity against Pseudomonas aeruginosa and weak antimicrobial activity against Escherichia coli, Staphylococcus albus, Staphylococcus aureus and Saccharomyces cerevisiae.
