Abstract

SCREENING OF LECTIN IN TUBERS OF ARACEAE AND PARTIAL CHARACTERIZATION OF XANTHOSOMA VIOLACEUM LECTIN (XVL)

Anitha N. and Sathisha G. J.*

Abstract

Present study describes the screening of lectin from different edible tubers belongs to Araceae family. Among the different tubers screened Xanthosoma Violaceum showed higher lectin activity and choosen for further studies. Crude lectin was extracted from Xanthosoma Violaceum tuber using various buffers like acetate buffer saline (pH- 4.3), Phosphate buffer saline (pH 7.2) and Tris buffer saline (pH-8.5). Heamagglutination activity was performed for the crude extract and partially purified lectin sample. XVL showed agglutination towards rabbit, goat, sheep, horse, cow, and pig erythrocytes but not towards human erythrocytes. Protein profiling of crude and ammonium sulphate fraction at different pH was done using SDS-PAGE. More number of proteins and large amount of lectin was extracted in both in PBS and TBS. Partially purified XVL was used for the determination of its carbohydrate specificity by heamagglutination inhibition assay. XVL activity was inhibited by simple sugars like galactose, mannose, glucosamine and also by complex glycoproteins such as thyroglobulin, transferrin, fetuin, asialofetuin, mucin, asialomucin, and ovalbumin. Partially purified lectin was stable over a wide range of pH 3.0 –8.5 and retains its activity up to 700C. The present investigation increases the knowledge about the occurrence of lectins and their contribution towards the medicinal properties of edible tubers of Araceae family.

Keywords: Xanthosoma violaceum, Araceae, Mannose, Lectins, Glycoproteins.