Slade et al. describe the application of TILLING to the identification of an allelic series of variants in the granule-bound starch synthase I (GBSSI) gene in hexaploid and tetraploid wheat. GBSSI or Waxy plays a critical role in the synthesis of amylose, which, in addition to amylopectin, comprises the starch fraction of the seed. Reduction or loss of GBSSI function results in starch with a de...

Novel amylose ester derivatives were synthesized and their chiral recognition abilities as chiral stationary phases for highperformance liquid chromatography were evaluated. Compared with amylose benzoate derivatives, cinnamate derivatives showed a higher chiral recognition ability and some racemates could be efficiently resolved. The recognition abilities of these derivatives varied significan...

The shx shrunken endosperm mutation of barley is the only one described with its primary effect on Type I, primer-independent soluble starch synthase (SSS). The mutant produces grains with only 31% of the normal dry weight of starch, associated with a decrease in A-granule dimensions. We investigated the structure of shx and normal cv. Bomi barley amylose and amylopectin. Surprisingly, both amy...

Starch present in the endosperm of common wheat (Triticum aestivum L.) grains is an important source of carbohydrates worldwide. Starches with a greater proportion of amylose have increased levels of resistant starch, a dietary fiber that can provide human health benefits. Induced mutations in STARCH BRANCHING ENZYME II (SBEII) genes in wheat are associated with increased amylose and resistant ...

Amylose and amylopectin are the 2 major components of plant storage starch. The rice starch branching enzyme (RBE) plays an important role in the starch components of rice. In the present study, we selected a specific 195-bp segment from the RBE3 gene to construct hairpin DNA, which was driven by an endosperm-specific high molecular weight glutenin promoter to regulate the biosynthesis of starc...

Background and Objectives: As chemical methods are commonly used to modify the starch properties, in this study, the influence of chemical modification using POCl3 on the rice starch function was evaluated. Materials and Methods: Rice starch was isolated by alkaline extraction of the proteins and cross-linked rice starches were prepared from reactions between native rice starch (low and high a...

Some physicochemical and cooking characteristics corresponding to different varieties and commercial samples of rice were analysed. Some mechanical properties determined by both, the viscoelastograf and the Instrom Universal Food Testing Machine were also analysed. Gelatinization time (Gt), gelatinization endotherm and amylose content were determined. The results showed that there was a very go...

The successful synthesis of amylose brushes via enzymatic "grafting from" polymerization and the detailed characterization of all synthetic steps by X-ray photoelectron spectroscopy (XPS) and spectroscopic ellipsometry measurements are reported. Au and Si surfaces are amino-functionalized with self-assembled monolayers (SAMs) of cystamine and 3-aminopropyldimethyethoxysilane (APDMES), respectiv...

To elucidate the relationship between the substrate size and geometric shape of the catalytic site of Thermus maltogenic amylase, Gly50, Asp109, and Val431, located at the interface of the dimer, were replaced with bulky amino acids. The k(cat)/K(m) value of the mutant for amylose increased significantly, whereas that for amylopectin decreased as compared to that of the wild-type enzyme. Thus, ...