A Comparison of the Protein and Amino Acid Composition of Old and Recent Barley Grain

Abstract

SUMMARYThe amino acid and protein contents of barley grain from archaeological sites dated between approximately 1000 and 3000 years B.C. have been compared with those of grain grown at Rothamsted between 1852 and 1977. The relative amino acid composition of the archaeological samples was remarkably similar to the recent grain, the main differences being decreased relative amounts of lysine and methionine. We were unable, however, to demonstrate the presence of salt-soluble proteins by electrophoresis or of hordein by electrophoresis or immunoassay. Salt-soluble protein and hordein fractions extracted from the oldest Rothamsted samples gave less clearly resolved patterns on electrophoresis and isoelectric focusing than fractions from recent grain, indicating some protein degradation. The rate of degradation was apparently faster for ' C' hordein than ' B' hordein polypeptides.Scanning electron microscopy showed little difference in the relative amounts of large and small starch grains in the different samples. Transmission electron microscopy showed that although the cells of the starchy endosperm of the 1000 B.C. grain were partially disorganized, they did contain structures which resembled the protein bodies present in similar sections of recent grain.

A multidisciplinary study of archaeological grape seeds

“…Ancient protein degradation is also confirmed by the diffuse smear present in the electrophoretic profile (Fig. 2 ), as previously reported by Shewry et al ( 1982 ), and by the ‘hump’ in the nano-LC chromatogram (cf. Fig.…”

“…2), as previously reported by Shewry et al (1982), and by the ‘hump’ in the nano-LC chromatogram (cf. Fig.…”

“…The protein component represents an important indicator of seed and grain quality. Pioneering studies on archaeological cereal seeds (Derbyshire et al 1977 ; Shewry et al 1982 ) suggested that the investigation of proteins from ancient grains could aid in understanding of plant domestication, but this work was hampered by the prevailing technology of that time. However, the application of mass spectrometry to fossil bone samples has enabled the identification and sequencing of single ancient proteins, namely osteocalcin (Nielsen-Marsh et al 2002 , 2005 ; Humpula et al 2007 ) and collagen (Asara et al 2007 ; Schweitzer et al 2009 ; but see also Buckley et al 2008 ).…”

125thAnniversary Review: Barley research in relation to Scotch whisky production: a journey to new frontiers

“…Shewry et al . and Palmer provide studies on some Egyptian material obtained from 3000 to 1000 BCE, which indicates some similarities to modern varieties particularly in the visible protein structures and amino acid composition , although the effects of time have made it somewhat unclear whether some of the detailed structures are truly comparable. However, Palmer suggests that the visible remains of the grain structures and endosperm of the material from ancient Egypt shows some evidence of some form of ‘malting’.…”

Amino acid analysis of food residues in pottery: a field and laboratory study

“…Studies show that food protein residues can remain relatively unchanged over long periods of time making identification possible. For example, Derbyshire et al (1977) found maize protein with a minimum age of 700 years to be relatively unaltered and Shewry et al (1982) found barley up to 5000 years old to have essentially the same amino acid makeup as modem samples. Evershed and Tuross (1996) did protein and amino acid analyses on experimental pottery and potsherds excavated from a Late Saxon/early Mediaeval site.…”