Fig 1.
Hydrophobicity-based fractionation of bromelain-generated stone fish protein hydrolysate (a) Chromatogram of semi-preparative RP-HPLC; (b) ACE-inhibitory activities of each of the potent fraction; (c) Relation between ACE-inhibitory activity and percentage acetonitrile being used.
Table 1.
ACE-inhibitory effect of the RP-HPLC fractions and IEF sub-fractions.
Fig 2.
ACE-inhibitory activity of bromelain-generated stone fish protein hydrolysate fractions at different isoelectric points along a pH gradient (3–10).
Fig 3.
MS/MS spectra, ion tables, MS/MS fragments and standard error of the potent peptide sequences with mw < 1000 Da: (a) Ala-Leu-Gly-Pro-Gln-Phe-Tyr (b) Lys-Val-Pro-Pro-Lys-Ala (c) Leu-Ala-Pro-Pro-Thr-Met (d) Glu-Val-Leu-Ile-Gln (e) Glu-His-Pro-Val-Leu.
Table 2.
Characteristics of the Potent ACE-inhibitory peptide sequences identified from the RP-HPLC fractions and IEF sub-fractions.
Table 3.
Estimated values of the GlideScore and binding energy for the best poses determined by molecular docking of stonefish-derived ACE-inhibitory peptides to the binding site of ACE.
Fig 4.
Predicted mode of binding of peptides and captopril docked to ACE.
(a) Ala-Leu-Gly-Pro-Gln-Phe-Tyr (b) Lys-Val-Pro-Pro-Lys-Ala (c) Leu-Ala-Pro-Pro-Thr-Met (d) Glu-Val-Leu-Ile-Gln (e) Glu-His-Pro-Val-Leu and (f) Captopril. Peptides are indicated as green lines, ACE residues are depicted as ribbon sticks, Different mode of interaction and selected distances are illustrated by dash lines and zinc ions are shown as cyan spheres.
Fig 5.
Predicted binding site for the 2D interaction of stone fish-derived ACE-inhibitory peptides with molecular surface of ACE; (a) Ala-Leu-Gly-Pro-Gln-Phe-Tyr (b) Lys-Val-Pro-Pro-Lys-Ala (c) Leu-Ala-Pro-Pro-Thr-Met (d) Glu-Val-Leu-Ile-Gln (e) Glu-His-Pro-Val-Leu and (f) Captopril as predicted by Schrödinger software.