Biological Properties and Characterization of Lectin from Red Kidney Bean (<i>Phaseolus Vulgaris</i>)

Abstract

Red kidney beans (Phaseolus vulgaris) contain significant amounts of lectins which have both beneficial and detrimental biological properties. Lectins are carbohydrate-binding glycoproteins that can react specifically with human blood cells, preferentially agglutinate malignant cells, and undergo mitogenic stimulation of lymphocytes. Some lectins are resistant to heat and proteolytic enzymes and can enter the circulatory system intact. Phytohaemagglutinin (PHA)—a lectin isolated from the red kidney bean—consists of four subunits with a molecular weight of 125 kDa. This bioactive compound has been partially purified by affinity chromatography using Affi-gel Blue. PHA has been shown to inhibit the viral enzymes, immunodeficiency virus type 1 reverse transcriptase (HIV-1 RT), and α- and β-glucosidases. This paper will review the chemical properties, biological activity, distribution, isolation, and heath benefits of red kidney bean lectin.