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Figure 1 Microscopic images of camelina seeds showing the effectiveness of Viscozyme® treatment on removing seed coat mucilage and cotyledon ultrastructure. Upper panels show dissecting light microscopic images. A dry seed with average length L and width W indicated (A), a seed showing the hydrated mucilage layer 1 h after hydration (B), and a dried seed after Viscozyme® treatment (C). Lower panels show TEM images of a cross-section of cotyledon cells with PSVs pointed by white arrows and OBs by white arrow heads (D), and OBs at a higher magnification with black arrows showing the oil body protein (OBP) layer (E).
Figure 2 Solubility of camelina meal proteins in relation to pH. Panel A: percentage solubility of the meal protein (%N × 6.25; one-time extraction) at different pH values. Panel B: polypeptide profile of soluble proteins at different pH vales. SDS-PAGE separation was under non-reducing conditions using 8-25% gradient gels. MWM=Molecular weight markers.
Figure 3 SDS-PAGE of polypeptides from camelina meal, purified cruciferin and napin. SDS-PAGE profiles of mucilage-reduced, oil-free meal (A), cruciferin-enriched fraction (B), and napin-enriched fraction (C) under reducing (+ME) and non-reducing (-ME) conditions. Molecular weight markers (MWM) are on the left-hand side of each panel with molecular weights (kDa) of the polypeptide bands shown in right hand margin of each sample lane in Panel A. Panels D and E show the native PAGE profile of purified cruciferin and napin, respectively. An 8-25% gradient gel was used for A, B, D and E, whereas a 20% gel was used for C. Bovine serum albumin (BSA) and urease were used as standards for native PAGE.
Figure 4 Two-dimensional electrophoresis separation profiles and reconstructed images for purified crucifern (A and B) and napin (C and D) from camelina meal. Numbers in B and D depict the protein spots in A and C, respectively, that were subjected to LC-MS/MS analysis. Cartoons in B and D approximate the size and staining intensity observed in A and C. MWM=Molecular weight markers (kDa).
Figure 5 Polypeptide profiles of OBP from camelina. Panel A: SDS-PAGE profile in one dimension of meal proteins, intermediate products (subnatant) and OBP under non-reducing (-ME) and reducing (+ME) conditions with estimated molecular masses (kDa) of the purified OBPs obtained using 8-25% gradient precast gels. (MWM=Molecular weight markers). Panels B and D: Two-dimensional electrophoresis separation of OBPs on 14% polyacrylamide gels obtained using first dimension IEF pH 3-10 (B) and pH 9-12 (D) followed by SDS-PAGE under non-reducing conditions for second dimension. Panels C and E: Graphical representation of B and D, respectively. Numbers in C and E depict the protein spots observed in A and D, respectively, that were subjected to LC-MS/MS analysis. Protein spot sizes in C and E approximate the size and staining intensity observed in B and D. (MWM=Molecular weight markers).
Figure 6 FTIR spectra of camelina cruciferin and napin together showing differences in in Amide I region and the regions of phosphorous containing functional groups. Separate small graphs are for the Fourier Self Deconvoluted (FSD) spectra of amide I region (1600-1690 cm-1) of cruciferin and napin showing peaks assigned for secondary structural components. FSD parameters: resolution enhancement factor (K) = 2.5 (cruciferin) and 2.8 (napin); full width of half height (FWHH) = 14 cm-1 (cruciferin) and 18 cm-1 (napin); apodization filter = Bassel (cruciferin and napin).
Figure 7 Changes observed in the far-UV CD spectra of purified camelina cruciferin (A) and napin (B) with the pH of the medium and the changes of Fluorescence intensity (C) and the maximum emission wavelength (λmax) (D) of Tryptophan residues of purified cruciferin as at ambient temperature (22°C).
Figure 8 Influence of temperature on tryptophan fluorescence of purified camelina cruciferin at different pH values. Change of fluorescence intensity (top plot in each panel) and maximum emission wavelength (λmax) (bottom plot in each panel) at pH 3 (A), pH 7 (B) and pH 10 (C). Values for F350/F330 ratio are provided in the top panel.