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 °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.