The constitution of Tamarindus‐amyloid

The preparation of Tamarindus‐amyloid from seeds of Tamarindus indica L. is described in detail. The product was homogeneous under conditions of free boundary electrophoresis and of sedimentation in the ultracentrifuge. A tentative value for a molecular weight of 115,000 was found. Partial hydrolysis of the polysaccharide with Myrotheciwn‐cellulase liberated a hepta‐, an octa‐ and a nona‐saccharide, while a fungal enzyme “Luizym” yielded 6‐O‐α‐D‐xylopyranosyl‐D‐glucopyranose. Partial hydrolysis with dilute mineral acid gave the disaccharide 2‐O‐β‐D‐galactopyranosyl‐D‐xylopyranose. Experimental evidence is presented for the following structural features: A main chain of β 1,4‐linked glucose residues. A xylose residue attached by an α 1,6‐linkage to three glucose residues out of every four. The three substituted glucose residues and the unsubstituted one alternate regularly. The galactose residues are attached to the xylose residues by β 1,2‐linkages. On the basis of this evidence a structure for Tamarindus‐amyloid is proposed.