The salt‐soluble proteins of barley. I.—a review

Abstract

The literature concerned with the composition of dialysed aqueous and saline extracts of barley grain has been reviewed, in particular in relation to the electrophoretic and ultracentrifugal analyses of the many fractions prepared from the extracts by precipitation with ammonium sulphate. The evidence suggests that at least the α‐globulin originally described by Quensel¹ is a mixture. Similarly, certain albumin preparations which sediment as single boundaries in the ultracentrifuge are shown by electrophoresis to be complex. On the other hand, the β‐ and γ‐globulins appear to be more homogeneous. No complete separation of albumins and globulins is apparently achieved by dialysing the extracts against water. It would appear that a group of non‐dialysable polypeptides which are not precipitated by ammonium sulphate constitute an important part of the nitrogenous fractions in the barley extracts.