Article ID | Journal | Published Year | Pages | File Type |
---|---|---|---|---|
7593646 | Food Chemistry | 2015 | 8 Pages |
Abstract
To examine the mechanisms in the interaction of sorghum procyanidins trimer (SPT) with porcine pancreatic α-amylase (PPA), fluorescence quenching, circular dichroism, and UV spectra methods were adopted. The procyanidins binding mode, binding constant and effect of procyanidins on protein stability and conformation were determined. The fluorescence spectroscopy results showed that the Stern-Volmer quenching constant KSV of SPT on PPA, bimolecular quenching constant kq, and apparent static quenching constant K were 2639.5 Mâ1, 2.6395 Ã 1011 Mâ1 sâ1, and 495.19 Mâ1, respectively. In addition, binding constant KA and number of binding sites were 872.971 Mâ1 and 1, respectively. Circular dichroism study revealed that PPA conformation was altered by SPT with a major reduction of β-sheet, increase of β-turn, minor change of random coil. UV spectra indicated that SPT influenced the micro-environment of aromatic amino acid residues in PPA. These findings directly elucidate the mechanisms of high molecular weight SPT in interaction with PPA.
Related Topics
Physical Sciences and Engineering
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Authors
Xin Cai, Jianan Yu, Liman Xu, Rui Liu, Jun Yang,