Study On Industrial Separation And Purification Technology Of Lactoferrin From Colostrum

Lactoferrin is a kind of glucoprotein combined with ferriion and other ions,which shows antibacterial,antiviral,immunity enhancement,tumor inhibition,coronary artery disease prevent ion and growth of beneficial bacteria promotion functions,and also it is an important raw material of food and drug industry.A combination of membrane separation and ion exchange resin purification technologies were applied in this study,and technical parameters were determined by pilot scale experiment,moreover,the purity of lactoferrin was improved in industry process.The economical and reliable methods,the efficient and practical technologies were utilized for high quality and high purity lactoferrin preparation.Three research contents were included in this study:1.Technical parameters reseach of lactoferrin separation by membrane.Taking colostrum as the raw material,the hybridprotein was removed after pretreatment, lactoferrin was separated by two ultrafiltration molecular.By single factor experiment and rotatory combination experiment,the process parameters were optimized as following:feed solution temperature 31.8℃,operating pressure of 0.20Mpa,pH7.0.Actual membrane flux 53.2L/m~2·h.Determined by spectrophotometric, the membrane performance was 0.79g/m~2·min,and the purity was 66.0±0.5%.The membrane was cleaned by water and alkali to reduce membrane clogging,the membrane flux recovery was 95%.2.Technical parameters research of i lactoferrin separation by ion exchange resin.Static adsorption test was applied for resin screening,based on the results of adsorption capacity and desorption,D151 was chosen from D151,D152,D113,DLT110 as the best resin for lactoferrin purification.The experiments were carried out to investigate the feed concentration,feed rate,elution rate,buffer system, and the conditions were optimized by L9(3~3)orthogonal test.The optimum process parameters were:0.3 and 0.9 mol/L NaCl two-step elution, buffer solution pH 7.0, feed concentration 20 mg/mL,feed rate 1.0 mL/min, elution rate 1.5 mL/min.The samples were desalinated and concentrated by 1 kDa molecular weight cut off(MWCO) membrane,and after vacuum freeze-dried,the purity of product was 90.6%±0.5%.3.Determination the pilot scale experiment parameters of lactoferrin purification by SMB.According to the paramters of ion-exchange purified from lactoferrin,and results of single column preparative chromatography validation test,combined with theoretical relations of TMB and SMB model,the industrialization technical parameters were designed and carried out with pilot scale experiment, the optimum SMB purification conditions were:switching time 780 s,feed flow rate 14.0 mL/min,elution flow rate 16.0 mL/min,regeneration flow rate 10.0 mL/min,washed flow rate 20.0 mL/min.The lactoferrin recovery rate was 93.5±0.5%.Detected by electrophoresis, and compared with Marker,the product was lactoferrin,and the purity was 95.8±0.5%.Compared with the cost of single-column preparative chromatography and SMBC purification lactoferrin, SMBC decreased 5 times of eluent amount,and only took 1/10 running time.