Comparative Electrophoretic Patterns of Albumins/ Globulins Extracted from Dry Grains and Green Malts of Barley Varieties

Polyacrylamide gel electrophoresis (PAGE) at acidic pH and sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) of barley seed storage proteins, hordeins, have been widely applied for barley variety discrimination (Cooke, 1995; Wrigley, 1995; White and Cooke, 1992). However, their use is limited to variety grouping, while full differentiation could not be achieved (Lamelland and Briand, 1990; Weiss et al., 1991b; Cooke, 1995; Wrigley, 1995; Bernardo et al., 1997; Binneck et al., 2002; Alvarez et al., 2006; Pan et al., 2007; Sipahi et al., 2010; Strelec et al., 2011). Therefore, useful modifications of standard separation methods or additional differentiation markers are desired. The search for them could include: (i) analysis of different stages of barley grain development, (ii) modification of extraction procedures, (iii) analysis of other protein fractions such as albumins/globulins, (iv) increasing resolution power of gels using gradient gels, (v) use of other electrophoretic separations such as isoelectric focusing or two dimensional-electrophoresis, and (vi) detection of specific group of proteins such as glycoproteins or various enzymes (Strelec et al., 2011; Finnie and Svensson, 2009; Cooke, 1995; Zhang and Jones, 1995; Görg et al., 1992; Weiss et al., 1992a; 1992b; 1991a; Ott and Scandalios, 1978). Analysis of albumins/globulins for barley varieties discrimination had limited capability, as reported by Weiss et al. (1991b). Electrophoretic patterns did not show significant differences between 20 German barley varieties, but allowed their grouping by glycoprotein patterns. Vaz et al. (2004) succeeded to group lupine varieties by electrophoretic separation of their globulins, and glycoprotein detection. Use of enzymes pattern profiling in variety differentiation has shown limited applicability. Görg et al. (1992) found α-amylase isoenzymes as suitable markers for barley malting quality, but differentiation of varieties by ISSN 1330-7142