Purification and Characterization of a New Phytolectin Extracted from Eucalyptus vicina Fruits with Immunomodulatory Effect

Plant-derived lectins are getting growing interest for their potential biomedical applications, however, there are few studies on lectins from Eucalyptus vicina fruits. The aim of the current study was to isolate and characterize a new phytolectin from Eucalyptus vicina fruits (EVL) and evaluate its immunomodulatory activity. EVL was purified through ammonium sulfate precipitation (70%) followed by ion-exchange chromatography. The purified protein appeared to have a molecular weight of around 55 kDa, determined using sodium dodecyl sulfate–polyacrylamide gel electrophoresis SDS-PAGE. EVL had strong hemagglutination activity against rabbit erythrocytes and all human blood types and displayed a high affinity against fetuin. The lectin exhibited optimal activity at alkaline pH (8–10) and was remarkably thermostable for 1 h at 70 degrees. Metal ions did not alter activity to a significant degree. The immunomodulatory effects were assessed in vivo using a carbon clearance assay, and EVL injection resulted in a dose-dependent increase in phagocytic activity. Overall, our data suggests that EVL could be a valuable candidate for research and future immunomodulatory therapies.