三、 Lu et al. used a comparative molecular field analysis (CoMFA) model to show a positive
correlation between C, M, the bulky C-terminal amino acid residue (R), the negatively charged
group around sulfur-containing amino acids, and the antioxidant activity of a nanopeptide with
the SYPTECRMR sequence obtained from sesame protein. The authors indicate that sulfur-
containing amino acids (C, M) as well as steric and electrostatic factors determine the antioxidant
activity of SYPTECRMR. Moreover, Zhang et al. reported that VEVYLPR and VVEVYLPR
peptides obtained from egg-white protein exhibited lower antioxidant activity than VYLPR,
which explains the fact that the position of glutamate
(E) in VEVYLPR and VVEVYLPR may
affect their antioxidant activity. Zhang et al. concluded that valine at the N-terminus of VYLPR
might be helpful to enhance the antioxidant activity of this peptide. Yang et al. showed that the
crucial antiradical activity against ABTS+• of a novel peptide ATVY was dependent on Tyr
positions in the N-terminus. In turn, Sheng et al. reported that the presence of antioxidant amino
acids (W, Y, and M) did not determine the cellular antioxidative effect of peptides. On the other
hand, Matsui et al. concluded that the antioxidant activities of tyrosine containing peptides GYG,
GYYG, and YGGY varied, depending on the characteristics of ROS and/or RNS. The author
showed that the number and position of Y in the peptides did not affect the antioxidant activity
against the ClO− ion, whereas the Tyr position was an important factor for the activity against
ONO2 −. In the case of ROO• , the number of Tyr residues influenced the antioxidant activity,
while its position did not have a significant effect. [Adopted from Foods 2020, 9, 846]
【題組】3. Please describe glutamate and valine significance for antioxidant activity from egg-white.