TY - JOUR
T1 - Purification and identification of endogenous antioxidant and ACE-inhibitory peptides from donkey milk by multidimensional liquid chromatography and nanoHPLC-high resolution mass spectrometry
AU - Zenezini Chiozzi, Riccardo
AU - Capriotti, Anna Laura
AU - Cavaliere, Chiara
AU - La Barbera, Giorgia
AU - Piovesana, Susy
AU - Samperi, Roberto
AU - Laganà, Aldo
PY - 2016/8/1
Y1 - 2016/8/1
N2 - Donkey milk is a valuable product for the food industry due to its nutraceutical, nutritional, and functional properties. In this work, the endogenous peptides from donkey milk were investigated for their antioxidant and ACE-inhibitory activities, combining a two-dimensional peptide fractionation strategy with high-resolution mass spectrometry, bioinformatics analysis, and in vitro assays. After extraction, the endogenous peptides were fractionated twice, first by polymeric reversed phase and then by hydrophilic interaction chromatography. Fractions were screened for the investigated bioactivities and only the most active ones were finally analyzed by nanoRP-HPLC-MS/MS; this approach allowed to reduce the total number of possible bioactive sequences. Results were further mined by in silico analysis using PeptideRanker, BioPep, and PepBank, which provided a bioactivity score to the identified peptides and matched sequences to known bioactive peptides, in order to select candidates for chemical synthesis. Thus, five peptides were prepared and then compared to the natural occurring ones, checking their retention times and fragmentation patterns in donkey milk alone and in spiked donkey milk samples. Pure peptide standards were finally in vitro tested for the specific bioactivity. In this way, two novel endogenous antioxidant peptides, namely EWFTFLKEAGQGAKDMWR and GQGAKDMWR, and two ACE-inhibitory peptides, namely REWFTFLK and MPFLKSPIVPF, were successfully validated from donkey milk. [Figure not available: see fulltext.]
AB - Donkey milk is a valuable product for the food industry due to its nutraceutical, nutritional, and functional properties. In this work, the endogenous peptides from donkey milk were investigated for their antioxidant and ACE-inhibitory activities, combining a two-dimensional peptide fractionation strategy with high-resolution mass spectrometry, bioinformatics analysis, and in vitro assays. After extraction, the endogenous peptides were fractionated twice, first by polymeric reversed phase and then by hydrophilic interaction chromatography. Fractions were screened for the investigated bioactivities and only the most active ones were finally analyzed by nanoRP-HPLC-MS/MS; this approach allowed to reduce the total number of possible bioactive sequences. Results were further mined by in silico analysis using PeptideRanker, BioPep, and PepBank, which provided a bioactivity score to the identified peptides and matched sequences to known bioactive peptides, in order to select candidates for chemical synthesis. Thus, five peptides were prepared and then compared to the natural occurring ones, checking their retention times and fragmentation patterns in donkey milk alone and in spiked donkey milk samples. Pure peptide standards were finally in vitro tested for the specific bioactivity. In this way, two novel endogenous antioxidant peptides, namely EWFTFLKEAGQGAKDMWR and GQGAKDMWR, and two ACE-inhibitory peptides, namely REWFTFLK and MPFLKSPIVPF, were successfully validated from donkey milk. [Figure not available: see fulltext.]
KW - ACE-inhibitory peptides
KW - Antioxidant peptides
KW - Donkey milk
KW - High-resolution mass spectrometry
KW - Off-line two-dimensional chromatography
KW - Peptidomics
UR - http://www.scopus.com/inward/record.url?scp=84975217767&partnerID=8YFLogxK
U2 - 10.1007/s00216-016-9672-z
DO - 10.1007/s00216-016-9672-z
M3 - Journal article
C2 - 27325462
AN - SCOPUS:84975217767
SN - 1618-2642
VL - 408
SP - 5657
EP - 5666
JO - Analytical and Bioanalytical Chemistry
JF - Analytical and Bioanalytical Chemistry
IS - 20
ER -