Abstract: Technological conditions on extracting  L-arginine from hair with subzero isoelectric point precipitation method were researched in this paper.The influences of hair hydrolization conditions,the preapitant type and dasage,the pH value,temperature,and the concentration of chlorine ion on the extraction rate of L-arginine were investigated.The experimental results show that the extraction rate of L-arginine can reach 0.139 g under the condition of pH10,temperature at 0 ℃,the bezaldehyde dasage of 2 mL,and the concentration of chlorine ion of 2.1 mol/L in 30 mL hair hydrolysate.

Key words: L-arginine, isoelectric point precipitation method, hair