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It has been ascertained in our laboratory that fucoidan, a polysaccharide contained in Saccharina japonica, shows anti-allergic activity through galectin 9 secretion in blood. A crude fucoidan fraction was chromatographically fractionated into three fractions using a Toyopearl-DEAE 650 M column in stepwise elusion with 0, 0.5 and 1.0 M NaCl in 0.05 M Tris-HCl buffer (pH 7.4). Each fraction was assessed using the passive cutaneous anaphylaxis (PCA) reaction. The non-absorbed fraction of the three fractions suppressed PCA, whereas the fractions eluted with 0.5 M and 1.0 M NaCl did not. Moreover, it was discovered that heat treatment of fucoidan at 50 °C for 10 min abolished its anti-allergic activity in the PCA reaction. Using DEAE chromatography, it was demonstrated that heat-treatment of the crude fucoidan fraction decreased the non-absorbed fraction, which possessed the anti-allergic activity, and increased the two fractions eluted with 0.5 M and 1.0 M NaCl. This clearly revealed the importance of temperature in maintaining the anti-allergic activity of fucoidan.

Fucoidan is a sulfated polysaccharide from brown sea algae. In the present study, it was demonstrated that oral administration of F-fucoidan from Saccharina japonica possessed anti-allergic effects using the passive cutaneous anaphylaxis reaction, but not by intraperitoneal administration. The inhibitory mechanism was dependent on galectin-9, which belongs to a soluble lectin family that recognizes β-galactoside and prevents IgE binding to mast cells. The anti-allergy properties of F-fucoidan were cancelled by an intravenous dose of anti-galectin-9 antibody or lactose, which bind competitively with galectin-9 before the passive cutaneous anaphylaxis reaction. F-fucoidan increased the expression level of galectin-9 mRNA in intestinal epithelial cells and serum galectin-9 levels. Oral treatment with F-fucoidan suppressed allergic symptoms through the induction of galectin-9. This is the first report that F-fucoidan can induce the secretion of galectin-9.

We purified a subtilase from digestive system of short spined sea urchin Strongylocentortus intermedius by a combination of ion-exchange chromatography and gel filtration. The molecular weight of purified subtilase on SDS-PAGE under both reducing and nonreducing conditions was 35,000. Antiserum against subtilase specifically immunostained its antigen. By Western blot analysis, immunoreactive with this antibody were observed in stomach and intestine.

The faculty development (FD) meeting began in the Faculty of Fisheries Sciences of Hokkaido University in 1999. In the FD meeting, the faculty members discuss various aspects of education methods, organization, cooperation between the faculty and administrative staff, etc. Orientation of teaching assistant candidates began in 2003. The faculty members also joined this orientation to talk with these candidates. The faculty committee of educational development and executive group for the FD meeting and teaching assistant (TA) orientation were officially established in 2005.