Characterization of bovine serum albumin and (-)-epigallocatechin gallate/3,4-O-dicaffeoylquinic acid/tannic acid layer-by-layer assembled microcapsule for protecting immunoglobulin G in stomach digestion and releasing in small intestinal tract
Chunxu Chen, Guijie Chen, Peng Wan, Dan Chen, Tao Zhu, Bing Hu, Yi Sun, Xiaoxiong Zeng
Journal of Agricultural and Food Chemistry
The protein-polyphenols layer-by-layer (LbL) assembled polymer composite microcapsule is a considerable delivery system that can be used to improve the bioactive stability and effectiveness of natural compounds in various applications. In the present study, three kinds of polyphenols were loaded in the sequence of (-)-epigallocatechin gallate (EGCG), 3,4-O-dicaffeoylquinic acid (3,4-diCQA) and tannin acid (TA) to prepare BSA-polyphenols LbL membrane. The composition of IgG-(BSA-EGCG/3,4-diCQA/TA)n microcapsule and its stability and releasing ability in gastrointestinal tract were evaluated. In addition, by binding these three kinds of polyphenols to BSA, the thermal denaturation temperature and ordered secondary structure of the BSA-polyphenols microcapsules were increased, and the time of scavenging activity on 2,2'-azinobis-(3-ethyl-benzothiazolin-6-sulfonic acid) free radicals was significantly prolonged. These findings suggest that the (BSA-EGCG/3,4-diCQA/TA)n microcapsule can not only protect IgG in food processing and stomach digestion, but also release it in small intestinal tract for bioactive delivery.
Circular dichroism, Secondary structure, Ligand binding, Biochemistry, Food science