Fractionation and characterisation ofj water‐soluble polysaccharide‐protein complexes containing hydroxyproline from the leaves of Vida faba

The water‐soluble polysaccharide‐protein complexes obtained previously by extraction with aqueous trichloroacetic acid and by phenol‐aqueous (pH 8) partitioning from the leaves of Vicia faba were fractionated into a number of components by continuous high voltage electrophoresis at pH 8.3 and 3.97 and by Sepharose 4B chromatography. The results indicated that these materials contained a spectrum of molecules with rather similar properties. All fractions obtained contained about 4–7% (wlw)lightly bound protein, two‐thirds of which was made up of four amino acids: hydroxyproline, alanine, serine and threonine. Similarly, all materials contained uronic acid (10–70%; w/w)and neutral sugars (10–90%; w/w), mainly arabinose and galactose. High uronic acid content was found to be associated with appreciable rhamnose content and an arabinose‐galactose ratio close to 2. This ratio became about 0.3 when the amount of uronic acids decreased to about 10% (w/w).