Abstract

ASSESSMENT OF ANTIMICROBIAL ACTIVITY OF A LECTIN ISOLATED AND PURIFIED FROM ADHATODA VASICA L.

Cyrilyuvaraj Sathish Claimer *, S. Ahmed John

Abstract

Adhatoda vasica belongs to a member of the family Acanthaceae. It is a well-known plant drug in Ayurvedic and Unani medicine and which is found in worldwide distribution. A lectin has been isolated from the leaves of Adhatoda vasica by the purification procedure of 80 % ammonium sulphate precipitation, followed by dialysis against 50 mM Tris HCl pH (7.6) and sephadex G -100 column chromatography. The Flow rate of 1.5 mL 12 min−1 fractions showed haemagglutinating activity against on rabbit 4% erythrocytes. The purified lectin named as Adhatoda vasica Lectin (AVL) results for molecular mass determinations produced a single band on SDS PAGE (20 KDa), revealing that tetrameric nature. It agglutinated against human A, B, AB, and O system, cow, sheep, Goat, mice, rabbit, and big erythrocytes and result that rabbit erythrocyte specificity. Haemagglutination was inhibited by D-galactose sugar specificity. The antimicrobial activity of the purified lectin was carried out by Agar disc diffusion using appropriate standards. The antimicrobial effect of AVL was evaluated by determining the minimal inhibitory, bactericide and fungicide concentrations. Highest bacteriostatic and bactericide effects were detected for S. paratyphi 13 mm μg ml-1 and antifungal activity 13.25 mm μg ml-1 S. aureus and S. epidermis MIC value (3.59, 2.5 and 1.72, 1.6)μg ml-1 E. coli and S. paratyphi respectively. The thermo stability of AVL is 30°C to 60°C. pH stability of the lectin in the range of 5 - 7. AVL confirmed a remarkable antibacterial activity against the pathogenic bacteria and inhibited the growth of fungi

Keywords: Adhatoda vasica Lectin; Haemagglutination; Lectin Isolation; Antimicrobial; Protein purification.