Chapter 21
Downloaded by UNIV OF GUELPH LIBRARY on July 19, 2012 | http://pubs.acs.org Publication Date: December 1, 2003 | doi: 10.1021/bk-2004-0871.ch021
Antioxidant Characterization of Caseinophosphopeptides from Bovine Milk S. C. K. Chiu and D. D. Kitts Department of Food, Nutrition, and Health, The University of British Columbia, 6650 Northwest Marine Drive, Vancouver, British Columbia V6T 1Z4, Canada
Bioactive peptides have been isolatedfromcasein hydrolysates and shown to have the affinity towards binding divalent metals such as calcium, zinc, copper, manganese and iron. The purpose of this study was to determine if tryptic digests of bovine milk casein deriving caseinophosphopeptides (CPP) carries the potential to hinder metal induced oxidation reactions through strong chelation with divalent metal catalysts. Using site-specific and non site-specific deoxyribose assays, CPP were found to significantly lower the level of secondary oxidation products and hence the extent of iron-mediated oxidation. In addition to secondary antioxidant activity, CPP also interacted directly with and stabilized free radicals such as ABTS radical, displaying yet another extraordinary property as a potential antioxidant.
© 2004 American Chemical Society In Nutraceutical Beverages; Shahidi, F., et al.; ACS Symposium Series; American Chemical Society: Washington, DC, 2003.
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280 Caseinophosphopeptides (CPP) are bioactive peptides derived from tryptic hydrolysis of bovine milk protein, casein. They are named phosphopeptides due to the presence of a high concentration of phosphorylated serine residues therein. The extent of phosphorylation is highly dependent on the type of caseins (a ,
25.5 ± 0.4
b y
χ 100
i
contro
2
Results are expressed as Mean ± SD, η = 3
3
Means within the same row that do not share a common superscript letter (a, b, c and d) are significantly differently (p
