The objective was to obtain the polysaccharide fraction present in the extracted polymeric matrix of a biofilm by differential precipitation of the protein content. This was tried by pH adjustment and by addition of trichloroacetic acid (TCA). The best yield of protein precipitation was with 20% (w/v) TCA, with more than 97% of the protein removed and without affecting the amount of polysaccharides in solution.
differential precipitation - polysaccharides - proteins