Indigofera<br />heterantha commonly called indigo bush is a<br />member of leguminoseae family found in the Himalayan region of Kashmir. A<br />lectin has been isolated from the seeds of Indigofera<br />heterantha by the purification procedure involving anion exchange chromatography<br />on DEAE-cellulose followed by gel filtration chromatography on Sephadex G 100.<br />Molecular characterization of the lectin was done by gel filtration and<br />SDS-PAGE. Activity of the lectin was checked by hemagglutination assay and the<br />sugar specificity by sugar inhibition tests. The antimicrobial activity of the<br />purified lectin was carried out by Agar disc diffusion using appropriate<br />standards. On the ion exchange column, the bound protein when eluted with 0-0.5 M NaCl gradient emerged as three peaks—peak I, peak II and peak III out of<br />which only peak II showed the hemagglutinating activity. The lectin further<br />resolved into two peaks G1 and G2 on gel filtration, with the lectin activity<br />residing in G1, corresponding to a molecular weight of 70 KDa. The purified<br />lectin named as Indigofera heterantha Lectin<br />(IHL) produced a single band on SDS PAGE (18 KDa), revealing the tetrameric<br />nature of the lectin. It agglutinated human erythrocytes (A, B, AB, and O).<br />Hemagglutination was inhibited by D-galactose, Dmannose and D-arabinose. The<br />lectin is reasonably thermostable showing full activity within a temperature<br />range of 30°C to 90°C. pH stability of the lectin falls in the range of 2-9.<br />IHL demonstrated a remarkable antibacterial activity against the pathogenic<br />bacteria Klebsiella pneumoniae, Staphylococcus aureus, Escherichia coli, and Bacillus subtilis. IHL also inhibited the growth of<br />phytopathogenic fungi Aspergillus niger, Aspergillus oryzae and Fusarium oxysporum.
Qadir, S., Hussain Wani, I., Rafiq, S., Ahmad Ganie, S., Masood, A., & Hamid, R. (2013). Evaluation of antimicrobial activity of a lectin isolated and purified from <i>Indigofera heterantha</i> Advances in Bioscience and Biotechnology, 04(11), 999–1006. https://doi.org/10.4236/abb.2013.411133