Physicochemical studies of caroubin: a gluten-like protein

It has been reported that caroubin, a protein mixture obtained from carob seeds, has rheological properties similar to those of gluten. Comparative studies of the effects of hydration and temperature on caroubin and gluten were carried out with the aid of NMR, FTIR, scanning electron microscopy, and differential scanning calorimetry techniques. The results show that caroubin has a more ordered structure than gluten and that hydration has little effect on its secondary structure when compared to gluten. Caroubin is more easily accessible to water than gluten, suggesting that caroubin is more hydrophilic in nature. On hydration, caroubin, like gluten, forms fibrillar structures and sheets.

Identification of genomes and chromosomes involved in peroxidase synthesis of wheat seeds

Polyacrylamide-slab gel electrophoresis of peroxidases of different Triticum and Aegilops species and of nullisomic–tetrasomic lines of Chinese spring wheat showed that T. aestivum chromosomes 7D, 4B, and 7A are the carriers of genes coding the synthesis of peroxidase a, peroxidase c, and peroxidase d, respectively. The indirect effect of modified chromosome systems and a special effect of chromosome 5B on peroxidase synthesis have also been observed. The chromosomal and genomic origin of the three other peroxidases (b, e, and f) detected in common wheat could not be definitively established.

[Purification and characterization of two peroxidases from hard wheat]

Two peroxidases A and B were purified from a borate buffer extract (pH = 10,4) of durum wheat semolina (Triticum durum), var. Bidi 17, by chromatography on DEAE-cellulose, salting out by 3M ammonium sulphate and two chromatographies on CM-cellulose; specific activities of peroxidase A or B were increased 114 or 66 fold. Molecular weight, amino acid composition, absorption spectrum, pH optimum, thermal stability and KM values differentiate the two enzymes. Ion Ca++ was shown as an activator of both peroxidase activities; the presence of an inhibitor in the crude extract was demonstrated.