Isolation, purification and characterization of antioxidant peptidic fractions from a bovine liver sarcoplasmic protein thermolysin hydrolyzate.
Sarcoplasmic proteins isolated from bovine livers were hydrolyzed using the enzyme thermolysin at 37°C for 2h. The hydrolyzates were filtered through molecular weight cut off membranes (MWCO) and filtrates were obtained. The water activity (a(w)) of unhydrolysed sarcoplasmic protein, full hydrolyzates, 10-kDa and 3-kDa filtrates were below the limit necessary for microbial growth. The antioxidant activities of both filtrates and fractions were assessed using the 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging activity assay, the ferric ion reducing antioxidant power (FRAP) assay and the Fe(2+) chelating ability assay. RP-HPLC was used for purification of the full hydrolyzates, the 10-kDa and the 3-kDa filtrates. The peptidic content of the full hydrolyzates, the 10-kDa and the 3-kDa filtrates were assessed using the Dumas method and peptide contents of each fraction were characterized using electrospray quadrupole time-of-flight (ESI-Q-TOF) mass spectrometry with the resultant spectrum analysed using the software programmes Protein Lynx Global Server 2.4. and TurboSEQUEST. Similarities between the amino acid composition of characterized peptides from each fraction and previously reported antioxidant peptides were found. This study demonstrates that meat by-product such as liver can be utilised as raw material for the generation of bioactive peptides with demonstrated antioxidant activities in vitro using the enzyme thermolysin. It is significant as it presents a potential opportunity for meat processors to use their waste streams for the generation of bioactive peptides for potential functional food use.
Food Chemistry and Technology Department, Teagasc Food Research Centre, Ashtown, Dublin 15, Ireland.
Roberta
R
Di Bernardini
Dilip K
DK
Rai
Declan
D
Bolton
Joseph
J
Kerry
Eileen
E
O'Neill
Anne Maria
AM
Mullen
Pádraigín
P
Harnedy
Maria
M
Hayes
D000595:Amino Acid Sequence; D000818:Animals; D000975:Antioxidants / Q000032:analysis / Q000737:chemistry*; D001713:Biphenyl Compounds / Q000737:chemistry; D002374:Catalase / Q000032:analysis / Q000378:metabolism; D002417:Cattle; D002712:Chlorides / Q000737:chemistry; D002851:Chromatography, High Pressure Liquid; D003593:Cytoplasm / Q000737:chemistry*; D050556:Fatty Acid-Binding Proteins / Q000032:analysis / Q000378:metabolism; D005290:Ferric Compounds / Q000737:chemistry; D005296:Ferrous Compounds / Q000737:chemistry; D005374:Filtration; D016166:Free Radical Scavengers / Q000737:chemistry; D007502:Iron Chelating Agents / Q000737:chemistry; D051037:Large-Conductance Calcium-Activated Potassium Channel alpha Subunits / Q000032:analysis / Q000378:metabolism; D008110:Liver Extracts / Q000737:chemistry* / Q000378:metabolism; D009584:Nitrogen / Q000032:analysis; D010455:Peptides / Q000032:analysis / Q000737:chemistry*; D010851:Picrates / Q000737:chemistry; D011492:Protein Hydrolysates / Q000032:analysis / Q000737:chemistry*; D011506:Proteins / Q000032:analysis / Q000737:chemistry / Q000378:metabolism*; D037662:Pulmonary Surfactant-Associated Protein A / Q000032:analysis / Q000378:metabolism; D021241:Spectrometry, Mass, Electrospray Ionization; D013820:Thermolysin / Q000378:metabolism*; D014867:Water / Q000032:analysis; D055542:alpha-Globins / Q000032:analysis / Q000378:metabolism; D055544:beta-Globins / Q000032:analysis / Q000378:metabolism; D055517:snRNP Core Proteins / Q000032:analysis / Q000378:metabolism
D000975:Antioxidants; D001713:Biphenyl Compounds; D002712:Chlorides; D050556:Fatty Acid-Binding Proteins; D005290:Ferric Compounds; D005296:Ferrous Compounds; D016166:Free Radical Scavengers; D007502:Iron Chelating Agents; D051037:Large-Conductance Calcium-Activated Potassium Channel alpha Subunits; D008110:Liver Extracts; D010455:Peptides; D010851:Picrates; D011492:Protein Hydrolysates; D011506:Proteins; D037662:Pulmonary Surfactant-Associated Protein A; D055542:alpha-Globins; D055544:beta-Globins; D055517:snRNP Core Proteins; D014867:Water; C004931:1,1-diphenyl-2-picrylhydrazyl; D002374:Catalase; D013820:Thermolysin; D009584:Nitrogen; C029451:ferrous chloride; C024555:ferric chloride