Identification of lectins from the seeds of Bangladeshi plants Sesbania bispinosa and Senna occidentalis by hemagglutination assay

Hemagglutination assay is a simple and easy method to specify a lectin. An active lectin agglutinates erythrocytes by recognizing a carbohydrate on the cell surface and forming a cross-linked network in suspension. The assay is traditionally performed on a microtiter plate, where the lectin solution is serially diluted and the minimum concentration of a lectin causing agglutination is detected. The crude extract of Senna occidentalis and Sesbania bispinosa seeds contain considerable amount of protein. It was found that 10 gm of Sesbania bispinosa and Senna occidentalis seeds contain about 12.6 mg/mL and 9.8 mg/mL of protein, and minimum agglutination concentration was found to be 0.393 mg/mL for Sesbania bispinosa in each group of human erythrocytes (A, B, O and AB) and 0.613 mg/mL for Senna occidentalis in chicken erythrocytes. Finally, the hemagglutination assay confirmed that possible lectins present in the Sesbania bispinosa and Senna occidentalis plant sources.