University of Surrey

Test tubes in the lab Research in the ATI Dance Research

Elucidation of bioactive properties of salmon skin proteins.

Leong, Pooi M. (2015) Elucidation of bioactive properties of salmon skin proteins. Doctoral thesis, University of Surrey.

[img] Text
corrected thesis.pdf - Thesis (version of record)
Restricted to Repository staff only until 31 August 2017.
Available under License Creative Commons Attribution Non-commercial No Derivatives.

Download (2MB) | Request a copy
[img] Text
embargo.pdf - Restricting access form
Restricted to Repository staff only
Available under License Creative Commons Attribution Non-commercial Share Alike.

Download (143kB) | Request a copy
[img] Text
2014_08_13_Author_Deposit_Agreement.docx - Other
Restricted to Repository staff only until 31 August 2017.
Available under License Creative Commons Attribution Non-commercial Share Alike.

Download (41kB) | Request a copy

Abstract

Bioactive peptides are peptides that are able to exert beneficial health effects apart from providing the nutritional aspect. In this study, bioactive peptides were produced and purified from alcalase hydrolysed Salmon skin gelatin. A gel filtration fraction, GF28, was identified as the most potent fraction. A further aim of this study was to investigate the bioactive properties including antioxidant, ACE inhibition, and anti-proliferative activities of the peptide. GF28 exhibited ACE inhibition activity of 46.5 %. Further studies elucidated GF28 acts as a competitive inhibitor of ACE. GF28 also exhibited comparable antioxidant activity to the positive control trolox (67.1 % and 67.3 % respectively). The antioxidant mechanism of GF28 mainly involved transition metal ion chelating activity and less reducing power activity. Apart from that, GF28 had poor radical scavenging activity in both hydrophobic and hydrophilic environments. GF28 also showed cytotoxic effects in hepatocellular carcinoma, HepG2 cells (IC50=0.154 mg/mL). In addition, GF28 also affected the endogenous antioxidant defence system in HepG2 cells by decreasing SOD, total glutathione and GPx activity. Catalase activity in GF28 treated HepG2 cells also increased. Anti-proliferative effects of GF28 were also observed in Caco-2 cells (IC50=0.16 mg/mL). In 0.15 mg/mL GF28 treated Caco-2 cells, intracellular and mitochondrial ROS (15.3 % and 7.8 % respectively) were significantly lower than untreated cells (32.9 % and 25.2 % respectively). Caco-2 cells treated with GF28 showed cell cycle arrest in the G1 phase as well as apoptosis. The extrinsic and intrinsic apoptosis pathway was activated with GF28. Caspase-8, caspase-3/7 and PARP were activated in the extrinsic pathway whereas caspase-9 and LaminA/C were activated in the intrinsic pathway.

Item Type: Thesis (Doctoral)
Divisions : Theses
Authors :
AuthorsEmailORCID
Leong, Pooi M.leong_pm@hotmail.comUNSPECIFIED
Date : 28 August 2015
Funders : European Commission FP7 for the project-Improving food security by reducing post harvest losses in the fisheries sector (SECUREFISH) (Grant number: 289282)
Contributors :
ContributionNameEmailORCID
Thesis supervisorHowell, Nazlin Kn.howell@surrey.ac.ukUNSPECIFIED
Depositing User : Pooimun Leong
Date Deposited : 08 Sep 2015 08:44
Last Modified : 08 Sep 2015 08:44
URI: http://epubs.surrey.ac.uk/id/eprint/808181

Actions (login required)

View Item View Item

Downloads

Downloads per month over past year


Information about this web site

© The University of Surrey, Guildford, Surrey, GU2 7XH, United Kingdom.
+44 (0)1483 300800