Chromatographic separation, fractionation and oxdation of selected beta-lactoglobulin peptides

Research output: ThesisMaster's thesisTheses

Abstract

The literature review elucidates the mechanism of oxidation in proteins and amino acids and
gives an overview of the detection and analysis of protein oxidation products as well as
information about β-lactoglobulin and studies carried out on modifications of this protein
under certain conditions. The experimental research included the fractionation of the tryptic
peptides of β-lactoglobulin using preparative-HPLC-MS and monitoring the oxidation
process of these peptides via reverse phase-HPLC-UV.
Peptides chosen to be oxidized were selected with respect to their amino acid content which
were susceptible to oxidation and fractionated according to their m/z values. These peptides
were: IPAVFK (m/z 674), ALPMHIR (m/z 838), LIVTQTMK (m/z 934) and
VLVLDTDYK (m/z 1066). Even though it was not possible to solely isolate the target
peptides due to co-elution of various fractions, the percentages of target peptides in the
samples were satisfactory to carry out the oxidation procedure.
IPAVFK and VLVLDTDYK fractions were found to yield the oxidation products reviewed
in literature, however, unoxidized peptides were still present in high amounts after 21 days
of oxidation. The UV data at 260 and 280 nm enabled to monitor both the main peptides
and the oxidation products due to the absorbance of aromatic side-chains these peptides
possess.
ALPMHIR and LIVTQTMK fractions were oxidatively consumed rapidly and oxidation
products of these peptides were observed even on day 0. High rates of depletion of these
peptides were acredited to the presence of His (H) and sulfur-containing side-chains of Met
(M).
In conclusion, selected peptides hold the potential to be utilized as marker peptides in
β-lactoglobulin oxidation.

Original languageEnglish
Publication statusPublished - 2010
MoE publication typeG2 Master's thesis, polytechnic Master's thesis

Fields of Science

  • 415 Other agricultural sciences
  • beta-lactoglobulin
  • protein oxidation
  • peptides
  • HPLC

Cite this

@phdthesis{6b203bc496284228b5a6eb4418fd476b,
title = "Chromatographic separation, fractionation and oxdation of selected beta-lactoglobulin peptides",
abstract = "The literature review elucidates the mechanism of oxidation in proteins and amino acids and gives an overview of the detection and analysis of protein oxidation products as well as information about β-lactoglobulin and studies carried out on modifications of this protein under certain conditions. The experimental research included the fractionation of the tryptic peptides of β-lactoglobulin using preparative-HPLC-MS and monitoring the oxidation process of these peptides via reverse phase-HPLC-UV. Peptides chosen to be oxidized were selected with respect to their amino acid content which were susceptible to oxidation and fractionated according to their m/z values. These peptides were: IPAVFK (m/z 674), ALPMHIR (m/z 838), LIVTQTMK (m/z 934) and VLVLDTDYK (m/z 1066). Even though it was not possible to solely isolate the target peptides due to co-elution of various fractions, the percentages of target peptides in the samples were satisfactory to carry out the oxidation procedure. IPAVFK and VLVLDTDYK fractions were found to yield the oxidation products reviewed in literature, however, unoxidized peptides were still present in high amounts after 21 days of oxidation. The UV data at 260 and 280 nm enabled to monitor both the main peptides and the oxidation products due to the absorbance of aromatic side-chains these peptides possess. ALPMHIR and LIVTQTMK fractions were oxidatively consumed rapidly and oxidation products of these peptides were observed even on day 0. High rates of depletion of these peptides were acredited to the presence of His (H) and sulfur-containing side-chains of Met (M). In conclusion, selected peptides hold the potential to be utilized as marker peptides in β-lactoglobulin oxidation.",
keywords = "415 Other agricultural sciences, beta-lactoglobulin, protein oxidation, peptides, HPLC",
author = "G{\"o}ker G{\"u}rb{\"u}z",
year = "2010",
language = "English",

}

TY - THES

T1 - Chromatographic separation, fractionation and oxdation of selected beta-lactoglobulin peptides

AU - Gürbüz, Göker

PY - 2010

Y1 - 2010

N2 - The literature review elucidates the mechanism of oxidation in proteins and amino acids and gives an overview of the detection and analysis of protein oxidation products as well as information about β-lactoglobulin and studies carried out on modifications of this protein under certain conditions. The experimental research included the fractionation of the tryptic peptides of β-lactoglobulin using preparative-HPLC-MS and monitoring the oxidation process of these peptides via reverse phase-HPLC-UV. Peptides chosen to be oxidized were selected with respect to their amino acid content which were susceptible to oxidation and fractionated according to their m/z values. These peptides were: IPAVFK (m/z 674), ALPMHIR (m/z 838), LIVTQTMK (m/z 934) and VLVLDTDYK (m/z 1066). Even though it was not possible to solely isolate the target peptides due to co-elution of various fractions, the percentages of target peptides in the samples were satisfactory to carry out the oxidation procedure. IPAVFK and VLVLDTDYK fractions were found to yield the oxidation products reviewed in literature, however, unoxidized peptides were still present in high amounts after 21 days of oxidation. The UV data at 260 and 280 nm enabled to monitor both the main peptides and the oxidation products due to the absorbance of aromatic side-chains these peptides possess. ALPMHIR and LIVTQTMK fractions were oxidatively consumed rapidly and oxidation products of these peptides were observed even on day 0. High rates of depletion of these peptides were acredited to the presence of His (H) and sulfur-containing side-chains of Met (M). In conclusion, selected peptides hold the potential to be utilized as marker peptides in β-lactoglobulin oxidation.

AB - The literature review elucidates the mechanism of oxidation in proteins and amino acids and gives an overview of the detection and analysis of protein oxidation products as well as information about β-lactoglobulin and studies carried out on modifications of this protein under certain conditions. The experimental research included the fractionation of the tryptic peptides of β-lactoglobulin using preparative-HPLC-MS and monitoring the oxidation process of these peptides via reverse phase-HPLC-UV. Peptides chosen to be oxidized were selected with respect to their amino acid content which were susceptible to oxidation and fractionated according to their m/z values. These peptides were: IPAVFK (m/z 674), ALPMHIR (m/z 838), LIVTQTMK (m/z 934) and VLVLDTDYK (m/z 1066). Even though it was not possible to solely isolate the target peptides due to co-elution of various fractions, the percentages of target peptides in the samples were satisfactory to carry out the oxidation procedure. IPAVFK and VLVLDTDYK fractions were found to yield the oxidation products reviewed in literature, however, unoxidized peptides were still present in high amounts after 21 days of oxidation. The UV data at 260 and 280 nm enabled to monitor both the main peptides and the oxidation products due to the absorbance of aromatic side-chains these peptides possess. ALPMHIR and LIVTQTMK fractions were oxidatively consumed rapidly and oxidation products of these peptides were observed even on day 0. High rates of depletion of these peptides were acredited to the presence of His (H) and sulfur-containing side-chains of Met (M). In conclusion, selected peptides hold the potential to be utilized as marker peptides in β-lactoglobulin oxidation.

KW - 415 Other agricultural sciences

KW - beta-lactoglobulin

KW - protein oxidation

KW - peptides

KW - HPLC

M3 - Master's thesis

ER -