Abstract: Extraction technology,molecular weight and amino acid composition of white kidney bean globulin were studied.The result showed that:the optimized extraction technology of globulin was as follows:concentration of NaCI 2.5 g/100 mL,solid-liquid ratio 1:22 (g/mL),extraction temperature 55 ℃,extraction time 5 h,and the extraction yield of globulin was 31.46% under the above conditions.The salting-out rate of globulin was 73.55%，when globulin was salted out at 4 ℃ for one hour by 60% ammonium sulphate saturation.Six protein subunit bands were detected in the SDSPAGE electrophoretogram of globulin,their relative molecular weights were 97.52,47.35,33.84,29.62,26.28 and 21.99 ku,respectively.Five bands were consistent with the subunit bands of isolated white kidney bean protein.In conclusion,globulin contained abundant amino acids,and the essential amino acid content was close to the FAO/WHO recommended pattern.It was a kind of high quality plant protein resource.

Key words: globulin, isolated protein, salting-out, molecular weight, amino acid analysis