A novel phytolectin purified from Eucalyptus vicina: properties and immunomodulatory activity

This study characterizes a novel lectin isolated from Eucalyptus vicina (EVL) fruits, an area of limited prior research. The lectin (EVL) was purified from fruit extract via ammonium sulfate precipitation followed by single-step ion-exchange chromatography. EVL exhibits a strong affinity for fetuin and demonstrates potent hemagglutination activity against rabbit and all human blood types. Size exclusion chromatography revealed a single 57 kDa peak in solution. Hemagglutination activity was optimal at alkaline pH (8-10) and was not affected by the presence of metals. Notably, EVL retained significant agglutination activity after one hour at 70°C, indicating thermostability. Furthermore, in vivo immunomodulatory effects were investigated using a carbon clearance assay. EVL administration resulted in a statistically significant, dose-dependent increase in phagocytic activity compared to the control group, suggesting its potential immunomodulatory properties.