发酵牛骨粉中小分子胶原多肽的超滤分离

应用超滤技术对发酵牛骨粉多肽进行分离,研究了超滤系统几个主要参数对膜通量的影响。确定了以下各超滤膜最佳的操作工艺参数。截留分子量(MWCO)10 kDa:多肽浓度为30 g/L、压力0.20~0.22 MPa、最佳料液温度30~35℃、pH值控制在6.0~7.0、运行周期为50 m in,膜透过速率为1.24 mL/m in;MWCO 6 kDa和4 kDa:多肽浓度为40 g/L、压力为0.20~0.22 MPa、温度低于45℃、自然pH值,运行周期为60 m in,膜透过速率为1.44 mL/m in和1.18 mL/m in;MWCO 2 kDa:多肽浓度为30 g/L、压力0.20~0.22 MPa、温度低于45℃、自然pH值,运行周期为50 m in,膜透过速率为1.01 mL/m in。超滤分离后分子量(MW)大于10 kDa和小于2 kDa的胶原多肽所占比例较多,分别为34.45%和33.94%。针对MWCO 10 kDa膜研究表明:随着超滤体积不断增加,膜透过速率不断下降;同时发酵液的水解度与总蛋白和总肽的透过率成正相关关系。

Ultrafiltration on Separation of Small Collagen Polypeptides from Fermented Bovine Bones

In this experiment,collagen polypeptides were separated by ultrafiltration.The effects of major ultrafiltration-system parameters on the filtrating velocity of membrane were studied.With the ultrafiltration membrane molecular weight cutoff(MWCO) 10 kDa,30 g/L of peptide concentration,50 min for a cycle at 0.20~0.22 MPa,30~35℃ and pH 6.0~7.0,the filtrating velocity of membrane would be about 1.24 mL/min.With the ultrafiltration membrane MWCO 6 kDa and 4 kDa,40 g/L of collagen polypeptide concentration,60 min for a cycle at 0.20~0.22 MPa,less than 45 ℃ and natural pH,the filtrating velocity of membrane would be about 1.44 mL/min and 1.18 mL/min,respectively.With the ultrafiltration membrane MWCO 2 kDa,30 g/L of collagen polypeptide concentration,50 min for a cycle,at 0.20~0.22 MPa,temperature less than 45℃ and natural pH,the filtrating velocity of membrane would be about 1.01 mL/min.Under these conditions,larger proportions of collagen polypeptides with molecular weight more than10 kDa and less than 2 kDa were 34.45% and 33.94% respectively.Ultrafiltration experiments for MWCO 10 kDa membrane showed that the average rate continuously dropped with the increasing volume.At the same time,it showed that the relationship of DH and the permeate of total protein and total peptides was positive correlation.