Comparison of EPS Extraction Efficiences from Cladophora Glomerata by Two Chemical Extraction Methods

For a macroalga Cladophora glomerata, the extracellular matrix on the surface of algae cell, extracellular polymeric substances (EPS) has a gel-like structure that could fractioned into loosely bound EPS (LB-EPS) and tightly bound EPS (TB-EPS). The ratio of protein to polysaccharides (P/S) is TB-EPS is higher than LB-EPS. The contents and extraction rate of EPS were compared two chemical extraction methods (formaldehyde-NaOH and NH4OH). The analysis demonstrated that more extraction rates of EPS were achieved by the formaldehyde-NaOH method. The protein to polysaccharides ratio(P/S) in EPS is between 0.299 to 0.375 by formaldehyde-NaOH and between 0.232 to 0.374 by NH4OH. The results indicated that the EPS could be efficiently extracted by the formaldehyde-NaOH method, but the influence of P/S ratios were not obvious.