Abstract: Fresh sword jackbean was used as material,and the best technological conditions for the extraction of sword jackbean lectin(SJL) were obtained in this study. The best conditions are as follows: extracting time 2.5 h,extracting temperature 22℃,concentration of NaCl in formic acid solution 0.20 mol/L,formic acid concentration 0.7 mol/L and ratio of material to water 1:50 (W/V). Under these conditions,the hemagglutinating activity of SJL is 102.96 HU/g,and the extraction mass of protein is 11.15 mg/g. By ammonium sulfate fractionation and dialysis,crude product of SJL is got. HPLC analysis showed that the preliminary product of SJL comprises a number of proteins with different molecular weights,in a wide range,from about 150000D to 1300D. The protein with the molecular weight of about 7100D accounts for 22.65%,and the protein with,the molecular weight of about 36000D accounts for 15.55%. The results showed that the content of sword jackbean lectin in the initial isolate is high.

Key words: sword jackbean, lectin, extraction and separation, analysis