Hyperproduction and application of alpha-agarase to enzymatic enhancement of antioxidant activity of porphyran.

The nucleotide sequence of the gene for the alpha-agarase, AgaA33, from Thalassomonas sp. strain JAMB-A33 was determined. The open reading frame for AgaA33 was revealed to encode 1463 amino acid residues. We succeeded in extracellular production of recombinant -agarase (AgaA33) efficiently using Bacillus subtilis as a host. This is the first report of recombinant production of -agarase. Furthermore, we demonstrated that hydrolysis of alpha-1,3 linkages in porphyran, a sulfated polysaccharide from marine red algae, by alpha-agarase is an important step for improvement of its antioxidant activity with regard to free-radical-scavenging capacity and superoxide radical anion scavenging activity, whereas the hydrolysis of beta-1,4 linkages in porphyran by beta-agarase did not increase on the antioxidant activity markedly.