In a preliminary study, the addition of antibiotics was shown to reduce bacterial concentrations in Entodinium exiguum cultures by more than 99% in 4 h, whereas the protozoal population was apparently unaffected. Using this procedure, the growth and amylolytic capability of Entodinium exiguum, in the presence or absence of live bacteria, was studied in vitro. Treatments for Trial 1 were protozo...

The evolution of metabolic pathways is a fundamental but poorly understood aspect of evolutionary change. One approach for understanding the complexity of pathway evolution is to examine the molecular evolution of genes that together comprise an integrated metabolic pathway. The rice endosperm starch biosynthetic pathway is one of the most thoroughly characterized metabolic pathways in plants, ...

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...

An F3 population consisting of 117 F2:3 families derived from a cross between two varieties of rice, Gongmi No. 3 and Diantun 502, with a large difference in their resistant starch and total alkaloid content, was used for quantitative trait locus (QTL) mapping. Two QTLs of resistant starch for rice (qRS7-1, qRS7-2) were identified in a linkage group on chromosome 7, which could explain phenotyp...

The inactivation of starch branching IIb (SBEIIb) in rice is traditionally associated with elevated apparent amylose content, increased peak gelatinization temperature, and a decreased proportion of short amylopectin branches. To elucidate further the structural and functional role of this enzyme, the phenotypic effects of down-regulating SBEIIb expression in rice endosperm were characterized b...

The influence of drying temperature on rice taste quality was studied in this paper. The heated-air temperature of 40°C, 45°C, 50°C, 55°C, and 60°C, respectively, were used to dry fresh paddy. The critical drying temperature of 45°C for paddy rice with an initial moisture content of 21.36% w.b. was obtained, which induce the rice taste value declining significantly. Also, the amorphous starch m...

Rice is staple food of Pakistani inhabitants and is a source of foreign exchange earnings. It is an immense source of starch. Rice starch is digested so quickly than any other high starchy food and this aspect make it distinctive among other cereals. The cooking and eating value is determined by the amylose content and gelatinization temperature. The cooking and eating characteristics of rice i...

Cereal Chem. 80(1):30–34 Flours and starches from rough rice dried using different treatment combinations of air temperature (T) and relative humidity (RH) were studied to better understand the effect of drying regime on rice functionality. Rough rice from cultivars Bengal and Cypress were dried to a moisture content of 12% by three drying regimes: low temperature (T 20°C, RH 50%), medium tempe...

Cereal Chem. 79(3):465–469 The structural features of rice starch that may contribute to differences in the functionality of three long-grain rice cultivars were studied. Dried rough rice samples of cultivars Cypress, Drew, and Wells were analyzed for milling quality, grain physical attributes, and starch structures and physicochemical properties. Drew was lower in head rice yield and transluce...

Octenyl succinic anhydride (OSA) modified early Indica rice starch was prepared in aqueous slurry systems using response surface methodology. The paste properties of the OSA starch were also investigated. Results indicated that the suitable parameters for the preparation of OSA starch from early Indica rice starch were as follows: reaction period 4 h, reaction temperature 33.4 °C, pH of reactio...