Inhibitor of α-Glucosidase (AGH, EC 3.2.1.20). IC50 = 3.7 ±
0.02 mM. Inhibitory activity of YYPL was ca. 140-fold weaker than that of a
voglibose, typical commercial therapeutic drug (Matsui et al., 1996)
(IC50 = 26 μM, Takeda Medical Co., Osaka, Japan). However, considering
that the peptides may be used as a physiologically functional food
component, the prophylactic effect in diabetes by food would be
substantial, regardless of its lower inhibition. The Lineweaver-Burk
plots for the inhibition of AGH showed the peptide inhibited AGH
competitively.
Table 1 AGH inhibitory activity of synthetic analogues of the peptide isolated from muscle hydrolyzate a
Sequence
| IC50 (mM)
| Tyr-Tyr-Pro-Leu
| 3.7 ± 0.02
| Tyr-Pro-Leu
| 3.9 ± 0.02
| Pro-Leu
| No inhibition
| Tyr-Pro
| 16.8 ± 0.08
| Tyr-Pro-Gly
| 5.0 ± 0.01
| Tyr-Pro-Tyr
| 25.8 ± 0.12
| a The analogue peptides were synthesized on the basis of the sequence of Tyr-Tyr-Pro-Leu isolated from the hydrolyzate.
|