[Extraction of agglutinin from Oncomelania hupensis and its haemagglutination activity].

Objective: To explore the extraction methods of agglutinin from Oncomelania hupensis snail and study its haemagglutination activity.

Methods: Protein obtained by ammonium sulfate fractionation precipitation with 20%-100% saturation of ammonium sulfate. Its haemagglutination activity was determined by rabbit erythrocytes. The precipitation which could agglutinate rabbit erythrocytes was diluted with 2.5 mg/ml D-galactose, D-fructose, D-glucose, saccharose, maltose and lactose, respectively, and then their haemagglutination activity was tested. Snail agglutinin were incubated at different temperatures (25-90 degrees C) and assayed for agglutinating activity. The effect of pH on the haemagglutination activity was determined by using the PBS buffer at different pH values (3.0-10.0).

Results: Oncomelania snail agglutinin exhibited high haemagglutination activity in 20%-40% saturated ammonium sulfate pellet. Lactose and galactose could inhibit the haemagglutination activity of snail agglutinin. The agglutinin showed maximum activity at pH 7.0. In temperature range of 30-70 degrees C, the haemagglutination activity decreased with increasing temperature, and all activity lost beyond 80 degrees C.

Conclusion: Galactose/lactose specific agglutinin exists in Oncomelania snail, its haemagglutination activity is affected by pH and temperature.