title: Binding of (-)-epigallocatechin-3-gallate with thermally-induced bovine serum albumin/ι-carrageenan particles.
abstract: Novel thermally-induced BSA/ι-carrageenan particles are used as a protective carrier for (-)-epigallocatechin-3-gallate (EGCG). The addition of EGCG to BSA/ι-carrageenan particles can highly quench the intrinsic fluorescence of BSA, which is explained in terms of the binding of EGCG to the hydrophobic pockets of BSA mainly through the hydrophobic force. According to the double logarithm equation, the binding constant is determined as 1.1×10(8)M(-1) for the binding of EGCG with BSA/ι-carrageenan particles. The high binding affinity is ascribed to both the molecular structure of EGCG and the partial unfolding state of BSA in BSA/ι-carrageenan particles. The circular dichroism spectra and calculated α-helix of BSA suggest that the bound EGCG leads to a more random secondary structure of BSA. Furthermore, BSA/ι-carrageenan particles are found to be superior to native BSA and pure BSA particles for improving the stability and radical scavenging activity of EGCG.
authors.affiliation: School of Chemistry and Molecular Engineering, East China University of Science and Technology, Shanghai 200237, China.
authors.forename: Jinbing
authors.initials: J
authors.lastname: Li
authors.affiliation: School of Chemistry and Molecular Engineering, East China University of Science and Technology, Shanghai 200237, China. Electronic address: xiaoyong@ecust.edu.cn.
authors.forename: Xiaoyong
authors.initials: X
authors.lastname: Wang
mesh_terms: D000818:Animals; D000975:Antioxidants / Q000737:chemistry; D002351:Carrageenan / Q000737:chemistry*; D002392:Catechin / Q000031:analogs & derivatives* / Q000737:chemistry / Q000378:metabolism; D002417:Cattle; D002942:Circular Dichroism; D005453:Fluorescence; D057927:Hydrophobic and Hydrophilic Interactions; D010316:Particle Size; D011485:Protein Binding; D017433:Protein Structure, Secondary; D012710:Serum Albumin, Bovine / Q000737:chemistry* / Q000378:metabolism; D013050:Spectrometry, Fluorescence; D013500:Surface Tension; D013696:Temperature
chemical_list: D000975:Antioxidants; D012710:Serum Albumin, Bovine; D002392:Catechin; D002351:Carrageenan; C045651:epigallocatechin gallate
keywords: Binding constant; Biopolymer particles; EGCG; Fluorescence; Stability