Mastocarpus stellatus as a source of R-phycoerythrin: optimization of enzyme assisted extraction using response surface methodology

This study reports the extraction of R-phycoerythrin (R-PE) from the red seaweed, Mastocarpus stellatus. Phosphate buffer 20 mM with pH 7.1 showed better results for R-PE extraction following classical maceration. The grinding of freeze dried material in liquid nitrogen aided greater extraction of R-PE. The treatment of freeze-dried seaweed with different cell-wall-degrading enzymes provided better results for R-PE yield than merely thawed algae. The enzyme xylanase was effective in degrading the cell wall polysaccharides of M. stellatus. The response surface methodology was employed in order to determine the optimal hydrolysis conditions of R-PE extraction: The optimum extraction conditions were as follows: temperature (12 A degrees C), pH (6.45), xylanase/dry seaweed ratio (13.18 mg. g(-1)) for 6 h in the dark. Under these optimal extraction conditions, the R-PE yield was 1.99 mg g(-1)dw which is about 1.8 times more than that of obtained for dry algae without optimization and six times more than that of obtained with wet algae treated with xylanase.