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 precipit-ation 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 ℃) 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 ℃,the haemagglutination activity decreased with increasing temperature,and all activity lost beyond 80 ℃.Conclusion Galactose/lactose specific agglutinin exists in Oncomelania snail,its haemagglutination activity is affected by pH and temperature.