No abstract

/npsi/ctrl?lang=en http://nparc.cisti-icist.nrc-cnrc.gc.ca/npsi/ctrl?lang=fr Access and use of this website and the material on it are subject to the Terms and Conditions set forth at http://nparc.cisti-icist.nrc-cnrc.gc.ca/npsi/jsp/nparc_cp.jsp?lang=en NRC Publications Archive Archives des publications du CNRCThis publication could be one of several versions: author's original, accepted manuscript or the publisher's version. / La version de cette publication peut être l'une des suivantes : la version prépublication de l'auteur, la version acceptée du manuscrit ou la version de l'éditeur. For the publisher's version, please access the DOI link below./ Pour consulter la version de l'éditeur, utilisez le lien DOI ci-dessous.http://dx.doi.org/10.1021/jf301847uJournal of Agricultural and Food Chemistry, 60, 35, pp. 8571-8579, 2012-08-16 Identification and quantification of Cyclolinopeptides in five flaxseed cultivars Gui, Bo; Shim, Youn Young; Datla, Raju S. S.; Covello, Patrick S.; Stone, Sandra L.; Reaney, Martin J. T. ABSTRACT: Cyclolinopeptides are a group of naturally occurring hydrophobic cyclic peptides found in flaxseed and flax oil that have immunosuppressive activity. This study describes the measurement of flaxseed cyclolinopeptide concentrations using an internal standard HPLC method. In addition, the concentration of cyclolinopeptides in the seed of Canadian flax cultivars grown at two locations over two years is reported. The data are consistent with the formation of flaxseed cyclolinopeptides from two ribosome-derived precursors. Each precursor protein includes the sequences corresponding to three cyclolinopeptides from which those cyclolinopeptides are presumably derived by precursor processing. The concentrations of cyclolinopeptides C and E, which are encoded by the same gene sequence, are highly correlated, and the concentrations of cyclolinopeptides D, F, and G, which are encoded by a second gene sequence, are also highly correlated. The strong correlation between the cyclolinopeptides arising from the same gene may prove to be important in understanding how peptide concentration is controlled. Additional research may lead to approaches to improve flax either as a platform for peptide production or as a source of oil with improved drying properties and flavor. Identification and Quantification of Cyclolinopeptides in

No abstract

Hydrophobic cyclic peptides, termed cyclolinopeptides, found in flaxseed are known for their immunosuppressive activity. This study is the first report of the occurrence of cyclolinopeptides in flaxseed fractions and products produced by aqueous processing and cold pressing. The distribution of cyclolinopeptides in flaxseed was determined after processing of flaxseed by various industrial and laboratory processes. Extracts of the water-soluble mucilage did not contain cyclolinopeptides. The cotyledon had the highest concentration of cyclolinopeptides, whereas seed coat had lower levels. An oil body fraction separated from seed after homogenization in water, followed by centrifugation, had the highest concentration of cyclolinopeptides of the fractions produced by this method. Further washing of the oil body fraction led to a loss of cyclolinopeptides. When oilseed was extruded using an expeller press, cyclolinopeptides were found in greater concentrations in crude oil and the solid sediment present in the oil fraction than in meal or the unprocessed seed. The concentration of cyclolinopeptides in crude flaxseed oil immediately after pressing was much higher than that observed in flaxseed oils purchased from a retail outlet. The effect of oil refining treatments on the removal of cyclolinopeptides was also tested. Acid degumming using aqueous H(3)PO(4) removed cyclolinopeptides from crude flaxseed oil. Alkali refining was less effective as this treatment failed to remove all peptides equally. This work illustrates ways that cyclolinopeptides may be extracted from flaxseed oil that could be developed for large-scale industrial extraction. The ability to extract cyclolinopeptides on a larger scale would allow faster exploitation of commercial applications of these molecules and provide the flaxseed industry with value-added coproducts.

The kinetics, energetics, and structure of Cyclolinopeptide A binding with Human Serum Albumin were investigated with surface plasmon resonance and circular dichroism. The complex is formed through slow recognition kinetics that is temperature sensitive in the range of 20°C–37°C. The overall reaction was observed to be endothermic (ΔH = 204 kJ mol−1) and entropy driven (ΔS = 746 J mol−1K−1) with overall small changes to the tertiary structure.