Study On Reducing Immunogenicity Of Bovine Milk β-lactoglobulin By Conjugation With Saccharides

Bovine milk is nutritious in multiple aspects,it has become the most suitable food source for infants.However,some infants are allergic to bovine milk.This is because bovine milk contains certain intense allergens.β-lactoglobulin(β-LG)is one of them.At present,the methods for resolving the problem almost all destroy the molecular structure of(3-LG,and make it lost the original function. Reports showed that the immunogenicity of P-LG was reduced by conjugation with saccharide,without destroying molecular structure and the function.The aim of this research is to find a method can reduce the immunogenicity ofβ-LG effectively and maintain the original molecular structure and function as far as possible.In this study,β-LG was obtained from Whey Protein Isolate(WPI)firstly,and was conjugated with the carboxymethylchitosan,chitooligosaccharide,isomaltooligosaccharide galactooligosaccharide and chitosan respectively by the maillard reaction then.Antigenicity and immunogenicity ofβ-LG-saccharides were investigated,and the molecular structure and function of the conjugates were analyzed.The present study indicated that,1)The antigenicity of bovine milkβ-LG was reduced by conjugation with galactooligosaccharide, carboxymethylchitosan,isomaltooligosaccharide and chitooligosaccharide,about 43%,39%,24%,21%.The antigenicity of theβ-LG-galactooligosaccharide was reduced most significantly.2)The immunogenicity ofβ-LG was reduced by conjugation with galactooligosaccharide and chitooligosaccharide.The immunogenicity reducing rate was 18%and 13%.The immunogenicity of theβ-LG-galactooligosaccharide was reduced most effectively.3)The molecular weight ofβ-LG-galactooligosaccharide was large slightly comparing toβ-LG, and still maintained in dimmer form.4)The emulsification stability,solubility,dispersion and thermal stability of theβ-LG-galactooligosaccharide were similar to those ofβ-LG,and antioxidant ability of theβ-LG-galactooligosaccharide was improved obviously.In conclusion,the conjugation of galactooligosaccharide withβ-LG was considered to be effective for decreasing the immunogenicity ofβ-LG,and maintained the original molecular structure and function ofβ-LG well.