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sorts of collagens present in the extracellular matrix. Collagen is the major structural component of connective tissues. All collagens contain collagen triple helices
which is primarily the recurrence of proline enriched tripeptide Gly-X-Y (Gelse
et al. 2003).
Gelatin is a soluble protein compound which is produced as a result of partial
hydrolysis of collagen (Johnston-Banks 1990). In a study, ACE inhibitory peptides
were isolated from the bovine skin gelatin hydrolysate. Five different proteases such
as α chymotrypsin, Alcalase, Pronase E, Neutrase, and trypsin were employed in the
study. The treatment of hydrolysate with enzyme was followed by ultrafiltration and
was finally treated with collagenase. Subsequently two BAPs with excellent ACE
inhibitory activity were isolated. The first peptide was named as EIIICIII and the
second peptide was named as EIIICIV, with IC 50 value of 4.7 μ M, and 2.55 μ M
respectively (Kim et al. 2001b).
Skin gelatin of fish Hoki on hydrolysis via enzymes released peptides that
showed potent biological action. Hydrolysis via tryptic enzyme released peptide,
which exhibited powerful action on DPPH and superoxide anion. Tryptic hydrolysis
released another peptide with specific sequence His-Gly-Pro-Leu-Gly-Pro-Leu
with strong radical scavenging ability (Mendis et al. 2005).
Chicken collagen was hydrolyzed by an Aspergillus oryzae protease and ACE
inhibitory hydrolysate were also obtained. The subsequent hydrolysate was further
treated with four different proteases, amino G, protease A, protease FP, and protease
N. Consequently, four different peptides exhibiting ACE inhibitory potential were
isolated and the IC 50 values of each were determined. The peptides were named as
GAHypGLHypGP, GAHypGPAGPGGIHypGERG, GLHypGSRGERGERGLHypG
and GIHypGERGPVGPSG with IC 50 values of 29.4, 45.6, 60.8 and 43.4 μ M
respectively. It was concluded in the study that low molecular weight chicken collagen hydrolysates had long-lasting hypotensive effects in vivo and can serve as
possible antihypertensive therapeutic agents (Saiga et al. 2008).
Fish peptides have significant biological activities against bacteria, viruses, and
fungi and used as immunomodulator, and antitumor agents. Recently, it is suggested, that almost all fish antimicrobial peptides possess antibacterial or bacteriostatic activities against several Gram-negative and -positive bacteria. A novel
20-residue antimicrobial peptide, pelteobagrin, was isolated from the skin mucus of
yellow catfish (Rajanbabu and Chen 2011).
In a study BAPs are obtained from the hydrolysis of squid (Dosidicus gigas)
by- collagen, by means of enzyme Protease type XIV. The protein hydrolysate
was further purified by ultrafiltration. After treatment with ultrafiltration membranes the BAPs from squid exhibited enhanced antioxidant and antimutagenic
activities but the antiproliferative activity did not improve after ultrafiltration
(UF) (Suárez- Jiménez et al. 2019). In another study, collagen remains from squid
skins were treated with Esperase and hydrolysate was obtained. This hydrolysate
was further fractionalized into three peptide fragments. The peptide sequence
with the lowest molecular weight exhibited maximum ACE inhibition ability
(Alemán et al. 2013).
5 Bioactive Peptides and Their Natural Sources
sorts of collagens present in the extracellular matrix. Collagen is the major structural component of connective tissues. All collagens contain collagen triple helices
which is primarily the recurrence of proline enriched tripeptide Gly-X-Y (Gelse
et al. 2003).
Gelatin is a soluble protein compound which is produced as a result of partial
hydrolysis of collagen (Johnston-Banks 1990). In a study, ACE inhibitory peptides
were isolated from the bovine skin gelatin hydrolysate. Five different proteases such
as α chymotrypsin, Alcalase, Pronase E, Neutrase, and trypsin were employed in the
study. The treatment of hydrolysate with enzyme was followed by ultrafiltration and
was finally treated with collagenase. Subsequently two BAPs with excellent ACE
inhibitory activity were isolated. The first peptide was named as EIIICIII and the
second peptide was named as EIIICIV, with IC 50 value of 4.7 μ M, and 2.55 μ M
respectively (Kim et al. 2001b).
Skin gelatin of fish Hoki on hydrolysis via enzymes released peptides that
showed potent biological action. Hydrolysis via tryptic enzyme released peptide,
which exhibited powerful action on DPPH and superoxide anion. Tryptic hydrolysis
released another peptide with specific sequence His-Gly-Pro-Leu-Gly-Pro-Leu
with strong radical scavenging ability (Mendis et al. 2005).
Chicken collagen was hydrolyzed by an Aspergillus oryzae protease and ACE
inhibitory hydrolysate were also obtained. The subsequent hydrolysate was further
treated with four different proteases, amino G, protease A, protease FP, and protease
N. Consequently, four different peptides exhibiting ACE inhibitory potential were
isolated and the IC 50 values of each were determined. The peptides were named as
GAHypGLHypGP, GAHypGPAGPGGIHypGERG, GLHypGSRGERGERGLHypG
and GIHypGERGPVGPSG with IC 50 values of 29.4, 45.6, 60.8 and 43.4 μ M
respectively. It was concluded in the study that low molecular weight chicken collagen hydrolysates had long-lasting hypotensive effects in vivo and can serve as
possible antihypertensive therapeutic agents (Saiga et al. 2008).
Fish peptides have significant biological activities against bacteria, viruses, and
fungi and used as immunomodulator, and antitumor agents. Recently, it is suggested, that almost all fish antimicrobial peptides possess antibacterial or bacteriostatic activities against several Gram-negative and -positive bacteria. A novel
20-residue antimicrobial peptide, pelteobagrin, was isolated from the skin mucus of
yellow catfish (Rajanbabu and Chen 2011).
In a study BAPs are obtained from the hydrolysis of squid (Dosidicus gigas)
by- collagen, by means of enzyme Protease type XIV. The protein hydrolysate
was further purified by ultrafiltration. After treatment with ultrafiltration membranes the BAPs from squid exhibited enhanced antioxidant and antimutagenic
activities but the antiproliferative activity did not improve after ultrafiltration
(UF) (Suárez- Jiménez et al. 2019). In another study, collagen remains from squid
skins were treated with Esperase and hydrolysate was obtained. This hydrolysate
was further fractionalized into three peptide fragments. The peptide sequence
with the lowest molecular weight exhibited maximum ACE inhibition ability
(Alemán et al. 2013).
5 Bioactive Peptides and Their Natural Sources