Applying Both Chemical Liquefaction and Enzymatic Catalysis Can Increase Production of Agaro-Oligosaccharides from Agarose

摘要

Red algae represents an important marine bioresource.One high-value utilization of red algae is the production of agarooligosaccharides which have many positive biological effects.However,the lack of an efficient production route seriously limits the application of agaro-oligosaccharides.In this study,we established a green route that combines chemical liquefaction and enzymatic catalysis for the efficient production of agaro-oligosaccharides,and we used the production of neoagarotetraose(NA4)as an example.Agarose(150 g L^−1)liquefaction by citric acid was controlled with respect to two targets:a 100%liquefaction rate and a high average degree of polymerization(>4)of the liquesced agaro-oligosaccharides,which were then catalyzed byβ-agarase into an oligosaccharides mixture with a high concentration of NA4(30.8 g L^−1)in a 1-L reaction volume.After purification,we obtained 25.5 g of NA4 with a purity of 92%.This work establishes an easy route for the efficient production of pure agaro-oligosaccharides from agarose.