Mung Bean Lectin Purification And Study Of Some Of It Properties

Lectin refers to a protein or a glycoprotein protein which is extracted from a variety ofplants, invertebrates and higher animals. Because of the agglutination of red blood cellsfunctions, which is wide spread in plants and animals, hence the name lectin. Lectins can be usedas research tools such as probes, and the study of lectin specificity is helpful to study the lifephenomena or atomic level because of its sugar binding specificity which is a combination ofspecificity from one lectin to a particular glycosylation. This paper we take measures to mungbeans with isolation and purification and take a preliminary study of some basic properties.We used coagulation method to detect the coagulation activity and dealed with fresh rabbitred cell as follows: glutaraldehyde concentration0.15%(v/v), fixed time15minutes and trypsinconcentration25U/mL,25℃processing for15minutes. These steps increasedsensitivity ofrabbit red blood cell agglutination and prolonged the rabbit red blood cells’ storage time.The extraction of mung bean agglutinin using phosphate buffer solution (PBS), the bestconditions of leaching solution as follows:0.2mol/L、pH7.2PBS. The mung bean powder wasdealed as follows: crush100mesh, solid to liquid ratio:0.09, NaCl concentration0.3mol/L,leaching time4.16h under20℃，and mung bean lectin agglutination activity in crude extracts is137.4U/mg. Agglutination activity reaches805.9U/mg when we collection50~60%saturatedsediment after ammonium sulfate double salting out of mung bean lectin’s crude extracts. Mungbean lectin agglutination activity of coagulation can arrive1307.8U/mg after extraction which isdealed with PEG600-ammonium sulfate aqueous two-phase system which contains15%PEG600,25%ammonium sulfate in mass fraction and mung bean lectin whose concentration is8.0mg/mL; After glucan gel filtration, the activity of agglutinin reaches1961.9U/mg.Mung bean lectin has strong ability to resist heat treatment. It also has a good tolerance toacid and it can still keep the clotting activity at low pH，between pH6.5~7.5they have thelargest lectin activity. Mung bean agglutinin SDS-PAGE electrophoresis showed two bands,lectin molecular weight about156.33KDa and ultraviolet absorption spectra show that it has thecharacteristic absorption peak at234nm and275nm.