Abstract: In order to clarify the physicochemical properties of Phaseolus vulgaris Phytohaemagglutinin（PHA） and promote its development and utilization， the effects of temperature， pH，denaturant，sugar-binding specificity，and metal ion on the activity of PHA were studied after separated and purified from fresh bean pods. At the same time，the difference in lectin activity in different legumes was also studied. The results showed that the coagulation activity of PHA was completely lost at 90 ℃ for 5 min. The agglutinin in the range of pH 2 ~ 13 had strong hemagglutination activity and strong acid-base stability. After treatment by EDTA，Fe²⁺ and Cu²⁺ could restore the hemagglutination activity of the common bean agglutinin，while Ca²⁺，Mg²⁺，and Zn²⁺ couldn't restore. D-fructose and L-rhamnose had inhibitory effects on the activity of PHA. The PHA was not sensitive to the tested denaturant. Only a high concentration of SDS and urea had some inhibitory effect on its hemagglutination activity. The order of hemagglutination activity of different leguminous plants was common bean > lentils > cat bean = cassia seed > sword bean = phaseolus coccineus > rice bean > cowpea = winged bean. The study clarifies the physical and chemical properties of PHA and its activity change rules. It provides a theoretical basis for regulating PHA activity intensity and facilitates the development and utilization of secondary metabolites.

Key words: common bean, Phytohaemagglutinin, physicochemical properties, haemagglutination activity