SPEC 70 SLS阳离子树脂分离牛乳中乳铁蛋白

Purification of lactoferrin from defatted milk with SPEC 70 SLS ion-exchange resin

建立了乳铁蛋白和乳过氧化物酶的反相液相色谱检测法;并采用SPEC 70 SLS离子交换树脂,研究了一步法分离脱脂牛乳中乳铁蛋白和乳过氧化物酶的工艺条件。高效液相条件:波长220 nm,流速1 mL/min,乙腈体积分数在20 min内从25%增加到75%。SPEC 70 SLS树脂静态吸附条件优化:温度15℃,pH7.0,时间3 h。在此条件下,乳铁蛋白标准品的吸附量(质量比)为22.0 mg/g。乳铁蛋白吸附过程符合Langmuir吸附等温线模型,最大吸附量为21.73 mg/g。在静态脱脂牛乳吸附过程中,乳铁蛋白和乳过氧化物酶的吸附量分别为7.64,6.89 mg/g,优于CM Sepharose FF和SP Sepharose FF。

The application of SPEC 70 SLS ion-exchange resin for directly isolation of lactoferrin and lactoperoxidase from non-pretreatment defatted milk was described.With detection wavelength 220 nm,flow rate 1 mL/min,acetonitrile volume fraction from 25% to 75% within 20 min,RP-HPLC method was developed to determine the volume fraction of lactoferrin and lactoperoxidase in peak fractions.The adsorption capability of SPEC 70 SLS resin towards pure lactoferrin was investigated.The static binding conditions of SPEC 70 SLS resin were optimized as follows： 15 ℃,pH 7.0 and adsorption time 3 h.Under such conditions,the adsorption capacity of lactoferrin（mass ratio） is 22.0 mg/g.The adsorption process can be well described by a Langmuir adsorption isotherm model,with a maximum adsorption capacity of 21.73 mg/g.In batch fractionation of defatted milk,the binding capacity of SPEC 70 SLS for adsorbing lactoferrin and lactoperoxidase simultaneously is 7.64 and 6.89 mg/g,respectively,which is superior to that with CM Sepharose Fast Flow and SP Sepharose Fast Flow.