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Background and objectives: Hard red wheat bran and hard white wheat bran were prehydrated and treated with cellulase, xylanase, or cellulase + xylanase to mitigate the adverse effects of bran on the bread‐baking quality of whole wheat meals. Findings: The hydration of bran with cellulase increased its soluble sugar content and decreased its soluble and insoluble fiber contents. Bran hydration with cellulase + xylanase was more effective at increasing soluble sugar and lowering insoluble fiber, indicating more extensive degradation of cell wall materials. The compositional changes of bran induced by hydration with cellulase or cellulase + xylanase affected the starch pasting and dough mixing properties of the flour–bran blends, showing delayed/inhibited starch gelatinization and decreased water absorption during dough development. A higher loaf volume was observed in bread containing bran hydrated with a low dose of xylanase or cellulase + xylanase in hard red wheat and in bread containing bran hydrated with low‐dose xylanase in hard white wheat. Conclusions: The prehydration of wheat bran with enzymes could effectively improve the baking quality of whole wheat meals prepared from flour–bran blends by inducing changes in the composition of bran and subsequently in the physicochemical properties of starch and gluten. Significance and novelty: The prehydration of wheat bran with enzymes can be an effective approach for enhancing whole wheat bread processing. [ABSTRACT FROM AUTHOR]

Background and objectives: Durum wheat (Triticum turgidum L. ssp. durum) may have advantages over bread wheat in making various styles of noodles due to low polyphenol oxidase (PPO) and high yellow pigment. However, the very hard kernel texture of durum wheat may pose a hindrance to its expanded utilization. The development of soft kernel durum wheat prompted this research into comparing the color of white salted, alkaline, and egg noodle sheets over time and three levels of hydration for one durum and 10 hexaploid wheat varieties. Findings: All noodle sheets darkened over time and "varieties" was a major source of variation. PPO activity was a poor predictor of noodle sheet brightness (L*) at 48 hr for all three styles of noodle. The soft durum variety "Soft Svevo" exhibited about average brightness but tended to have low discoloration (ΔL*) over time. The range in the green‐red axis, a*, was small, and all noodle sheets exhibited a small positive increase with most values near the neutral gray value. All noodle sheets were yellow, with Soft Svevo being markedly more yellow in all three formulations. The alkaline pH increased average yellowness by three units overall, but in Soft Svevo, not at all. In some varieties, a decrease in yellow color occurred from 6 to 48 hr. Conclusions: The low PPO activity of Soft Svevo did not predict an advantage in white salted, alkaline, and egg noodle sheet brightness over the "best" hexaploid wheat varieties. The reason was not resolved but may be related to marked differences in protein content of the flours. Significance and novelty: Soft kernel durum wheat exhibited some advantages over hexaploid wheat, particularly in low discoloration (ΔL*) and high yellow color. In no way was soft durum found to be inferior to hexaploid wheat. [ABSTRACT FROM AUTHOR]

The effect of bran prehydration on the composition and bread-baking quality was determined using bran and flour of two wheat varieties. Bran was hydrated in sodium acetate buffer (50mM, pH 5.3) to 50% moisture at 25 or 55°C for 1.5 or 12 h. The soluble sugar content in bran increased with prehydration. Decreases in phytate and soluble fiber were observed in prehydrated bran, but insoluble fiber was not affected by prehydration. Likewise, free phenolic content decreased, and there was little change in the content o f bound phenolics in prehydrated bran. The compositional changes were greater in the bran prehydrated at 55 than at 25°C, and for 12 than for 1.5 h. Addition of prehydrated bran delayed dough development of bran and flour blends and slightly increased water absorption of dough. A higher loaf volume of fresh bread and lower crumb firmness of bread stored for 10 days were observed in bread containing bran prehydrated at 25°C than in bread containing nonhydrated bran or bran prehydrated at 55°C. The prehydration of bran at 25°C before being incorporated into refined flour for dough mixing improved bread quality by altering bran compositional properties, allowing enough water to be absorbed by fibrous materials in the bran and preventing water competition among dough constituents. [ABSTRACT FROM AUTHOR]

The effects of organic versus conventional farming practices on wheat functional and nutritional characteristics were compared. Soft white winter wheat and hard red spring wheat were obtained from multiyear replicated field plots near Pullman, Washington, and Bozeman, Montana. Test weight, kernel weight, and kernel diameter tended to be greater in both soft and hard organic wheat than in conventional wheat in the Pullman studies. Phenolic content and total antioxidant capacity tended to be lower in organic than in conventional wheat. Flour ash, P, and Mg contents in whole wheat flour varied in parallel among cropping systems, but levels were not consistently associated with either organic or conventional cropping systems. Protein contents of whole wheat and refined flours were similar in organic and conventional wheat from Pullman when fertility levels were similar. Higher fertility was associated with higher protein content in both organic and conventional cropping systems. Soft wheat flour from a low‐fertility organic cropping system had lower sodium carbonate, lactic acid, and sucrose solvent retention capacities, lower protein content, and greater cookie diameter and cake volume than soft wheat flour from the higher fertility organic and conventional cropping systems; the change in end‐product quality was significant in one out of two crop years. In the Bozeman hard wheat studies, higher fertility in both organic and conventional cropping systems tended to increase protein content and bread loaf volume. Results indicated that neither organic nor conventional cropping systems were associated with substantially improved mineral and antioxidant nutritional properties, and end‐use quality of wheat was more strongly associated with fertility level than with organic versus conventional cropping systems. [ABSTRACT FROM AUTHOR]

Phytochemical profile (phenolic acids, carotenoids, and tocopherols) and antiproliferative properties of bread processing fractions, including the dough, crumb, and upper crust made from refined wheat and whole wheat flours were analyzed for two wheat cultivars. Ferulic acid, lutein, and α‐tocopherol were the predominant phenolic acid, carotenoid, and tocopherol, respectively, extracted from all fractions. The levels of all phytochemicals in whole wheat samples were over eightfold higher than their corresponding refined wheat samples. The concentrations of total phenolic acids (soluble and insoluble bound) were higher in the upper crust of refined (∼60–90%) and whole wheat (∼15–40%) breads than their corresponding dough fractions. However, the dough of whole wheat had higher levels of tocopherols and carotenoids compared with the crumb and upper crust, suggesting that phenolic acids were relatively stable during baking, whereas tocopherols (∼25–80%) and carotenoids (∼20–80%), were partially degraded. The antiproliferative activity of whole wheat bread extracts against HT‐29 cancer cells was weakly correlated with total phenolic acids but showed no correlations with total carotenoid and total tocopherol contents. [ABSTRACT FROM AUTHOR]

The effects of no‐till versus conventional farming practices were evaluated on soft wheat functional and nutritional characteristics, including kernel physical properties, whole wheat composition, antioxidant activity, and end‐product quality. Soft white winter wheat cultivar ORCF 102 was evaluated over a two‐year period from three long‐term replicated no‐till versus conventional tillage studies in Oregon. Wheat from the no‐till cropping systems generally had greater test weight, kernel diameter, and kernel weight and had softer kernels compared with wheat from the conventional tillage systems. Compared with the conventional systems, no‐till whole wheat flour had lower protein and SDS sedimentation volume. Ash content as well as most minerals measured (calcium, copper, iron, magnesium, and zinc), except for manganese and phosphorus, were generally slightly lower in no‐till than in conventional wheat. Whole wheat flour from the no‐till cropping systems generally had slightly lower total phenolic content and total antioxidant capacity. Milling properties, including flour yield, break flour yield, and mill score, were not affected by tillage systems. Refined flour from no‐till systems had lower protein, SDS sedimentation volume, and lactic acid and sucrose solvent retention capacities compared with flour from conventional tillage. No‐till wheat generally had greater sugar‐snap cookie diameter than conventionally tilled wheat. In conclusion, no‐till soft white winter wheat generally had slightly reduced nutritional properties (protein, ash, most minerals, and total antioxidant content) compared with wheat from conventionally tilled systems, and it had equivalent or sometimes superior functional properties for baking cookie‐type products. [ABSTRACT FROM AUTHOR]

End‐use quality in soft wheat (Triticum aestivum L.) can be assessed by a wide array of measurements, generally categorized into grain, milling, and baking characteristics. Samples were obtained from four U.S. regional nurseries. Selected parameters included test weight, kernel hardness, kernel size, kernel diameter, wheat protein, polyphenol oxidase activity, flour yield, break flour yield, flour ash content, milling score, flour protein content, flour SDS sedimentation volume, flour swelling volume, Rapid Visco Analyzer peak paste viscosity, solvent retention capacity (SRC) parameters, total and water‐extractable arabinoxylan (TAX and WEAX, respectively), and cookie diameter. The objectives were to model cookie diameter and lactic acid SRC as well as to compare exceptionally performing varieties for each quality parameter. Cookie diameter and lactic acid SRC were modeled by using multiple regression analyses and all of the aforementioned quality parameters. Cookie diameter was positively associated with peak paste viscosity and was negatively associated with or modeled by kernel hardness, flour protein content, sodium carbonate SRC, lactic acid SRC, and water SRC. Lactic acid SRC was positively modeled by break flour yield, milling score, flour SDS sedimentation volume, and sucrose SRC and was negatively modeled by flour protein content. Exceptionally high‐ and low‐performing varieties were selected on the basis of their responses to the aforementioned characteristics in each nursery. High‐ and low‐performing varieties exhibited notably wide variation in kernel hardness, break flour yield, milling score, sodium carbonate SRC, sucrose SRC, water SRC, TAX content, and cookie diameter. This high level of variation in variety performance can facilitate selection for improved quality based on exceptional performance in one or more of these traits. The models described allow a more focused approach toward predicting soft wheat quality. [ABSTRACT FROM AUTHOR]

Arabinoxylans (AX) are well known to have a wide‐ranging influence on wheat (Triticum aestivum L.) end‐use quality and are associated with health benefits. There is little information on the effects of processing on AX properties in high‐water‐content batter‐based products and on the associations between AX properties and end‐use quality in such products. The objective of this study was to track total and water‐extractable AX (TAX and WEAX, respectively) contents and determine changes in AX characteristics throughout the baking process of pancakes, a batter‐based wheat product. The TAX and WEAX contents along with the arabinose‐to‐xylose (A/X) ratio were quantified in refined flour and wholemeal as well as batter and pancakes from two soft and three hard wheat varieties. ANOVA F values indicated that the variation in TAX content was influenced most by sample type differences (flour versus batter versus pancakes), whereas varietal differences were responsible for the greatest differences in WEAX. In separate analyses on refined and wholemeal flours, the highest F values were for variety WEAX, largely attributed to the higher WEAX content of the three hard varieties. WEAX levels generally increased slightly from flour to batter to pancakes in refined flour. The WEAX content in flour, batter, and pancakes of both refined flour and wholemeal was highly correlated with pancake volume. These observations suggest moderate changes in wheat AX characteristics during processing and a positive association of WEAX levels with end‐product volume in a batter‐based product. [ABSTRACT FROM AUTHOR]

Recent attention to dietary fiber in wheat (Triticum aestivum L.) has invigorated research in the nonstarch carbohydrate arabinoxylan (AX). AX molecules are composed of a linear xylose backbone with arabinose substitutions along the backbone. These arabinose substituents can also carry a ferulic acid moiety. AX molecules can be fractionated into two categories based on extraction properties that have a structural and conformational basis: water‐extractable (WEAX) and water‐unextractable (WUAX) molecules. The ferulic acid moieties also allow for oxidative cross‐linking between AX molecules or the tyrosine residues of proteins. The contents of total AX and WEAX molecules are primarily influenced by genetic differences; however, there is also evidence of environmental influence on content. There are several useful methods for quantifying AX molecules, providing varying levels of structural information as well as accuracy and precision. The high water‐absorption capacity of AX molecules results in a strong influence of AX on end‐use quality. Whereas WEAX molecules, in particular, tend to be detrimental for the quality of soft wheat products such as cookies, WEAX molecules are beneficial to the quality of hard wheat products such as bread. The role of WUAX molecules among the range of soft wheat products is as yet unclear; however, WUAX molecules tend to have a detrimental influence on bread. Because of the variable influence of AX structure on end‐use product functionality, closer examination of structure–function relationships may provide key insights into how to direct breeding efforts to maximize these relationships between AX molecules and other ingredients. Further investigation is necessary to obtain a more complete understanding of how the arabinose substitution levels and patterns affect end‐use quality and how the genetic basis of these traits can be resolved and manipulated for optimum end‐use quality. [ABSTRACT FROM AUTHOR]

Wheat (Triticum aestivum L.) quality is dependent upon both genetic and environmental factors, which work in concert to produce specific grain, milling, flour, and baking characteristics. This study surveyed all of the 132 soft wheat varieties (cultivars and advanced breeding lines) grown in the U.S. regional nursery system, which encompassed the three main soft wheat producing regions of the United States (eastern and southern soft red winter and western soft white). The quality parameters included test weight, kernel hardness, weight, and diameter, wheat and flour protein, polyphenol oxidase, break flour yield, flour yield, flour ash, milling score, flour swelling volume, flour SDS sedimentation volume, solvent retention capacity (SRC) for water, sodium carbonate, sucrose, and lactic acid, Rapid Visco Analyzer peak pasting viscosity, and cookie diameter. High levels of variation were observed among varieties, regions, and specific environments, with environment being in general a much greater source of variation than varieties. Variety was observed to have a relatively stronger influence on wheat quality in the western nurseries, compared with the eastern and southern regions, where location effects had a stronger impact on overall wheat quality. The greater influence of variety was particularly notable for kernel hardness in the western nurseries. Kernel hardness also varied considerably as a result of environment. For the two soft red winter wheat nurseries, the western U.S. environment produced substantially harder kernels (37–40) compared with the same varieties grown in eastern U.S. locations (15–20). Intertrait quality relationships were observed to be unique to the specific nursery and germplasm in which they were studied, and these relationships were not consistent across nurseries. Nevertheless, on average, soft wheat quality was fairly similar across the United States, indicating that breeding and testing models have been successful in achieving a relatively uniform target for quality. However, many traits showed high levels of variability among varieties, suggesting that a greater level of selection for end‐use quality would benefit end users by increasing consistency and reducing variability. The often large role of environment (location) in quality indicates that end users must be assiduous in their origination and grain procurement. Clearly, “nursery mean” quality does not reflect the potential that can be obtained, as reflected by a few exceptional soft wheat varieties. [ABSTRACT FROM AUTHOR]

Hybridization and introgression continue to gain recognition as important issues in the management and conservation of native fishes. It is often necessary to identify hybrids in natural populations and to distinguish among individuals of various hybrid categories. Molecular methods are important for these purposes, and it is valuable if researchers have a range of molecular methods to apply, since each method has unique advantages and disadvantages. The determination of the best class of marker for a particular study depends on various factors, including the goals of the study, the resolution required, and the genomic and marker information already available for the taxa of interest. We modified a protocol to generate fluorescent randomly amplified polymorphic DNA (FRAPD) markers for hybridization studies. To our knowledge, this type of marker has not previously been used for hybrid identification. To demonstrate the utility of the modified methods, FRAPD markers were used to evaluate potential reproduction by saugeye (female walleye Sander vitreus × male sauger Sander canadensis) in a central Ohio reservoir. Our approach successfully generated a battery of diagnostic genetic markers that were used to test the hypothesis that young-of-year saugeye were later-generation offspring of saugeye cohorts previously stocked into the reservoir. Alternatively, the fish may have been immigrant first-generation saugeye from other sources. Data obtained from the FRAPD markers provided strong support favoring the alternative hypothesis. These methods provide a very useful tool for distinguishing between pure parentals and various classes of hybrid individuals, both in Sander spp. and in other taxa, offering a powerful and easily developed alternative to other molecular methods of generating informative genetic markers for hybridization studies. Received September 20, 2011; accepted April 5, 2012 [ABSTRACT FROM AUTHOR]

The article explores the discovery and characterization of super soft kernel texture trait in wheat. The study indicates the minimal impact of near-infrared (NIR) hardness and that it is associated to the yield of superior break flour in milling. It stresses the potential contribution of NIR hardness in enhancing the quality of the cake. It also notes the opportunities provided by the trait with the wheat breeders in the modification of end-use wheat quality.

As evolutionary relationships within the order Acipenseriformes are not well understood and some classifications are currently controversial, the study of evolutionary relationships, especially based on genetic data, has received much recent attention. In this reanalysis we present a nearly complete proposed phylogeny of the order, including 25 species, based on the maximum likelihood analysis of combined DNA sequence data (4406 base pairs) from five mitochondrial genes sequenced in our laboratories (cytochrome b, 12S rRNA, cytochrome c oxidase subunit II, tRNAAsp and tRNAPhe) and three mitochondrial gene regions sequenced by Birstein et al. (2002) (16S rRNA, NADH5 and control region). Examination of the molecular phylogeny using either maximum likelihood, Bayesian analysis, maximum parsimony or neighbor-joining leads to the following conclusions: (i) the two species of paddlefish do form a clade; (ii) the most basal position within the Acipenseridae remains unresolved, held either by the genus Scaphirhynchus or by the clade containing Acipenser oxyrinchus and A. sturio; (iii) Huso is not monophyletic, with the two species of Huso found embedded separately within the genus Acipenser; (iv) A. sinensis and A. dabryanus are confirmed as closely related; (v) the previously described Atlantic-Pacific subdivision within the Acipenser/Huso complex is supported and (vi) the unexpected placement of Pseudoscaphirhynchus kaufmanni within Acipenser is supported by this analysis. These results offer further evidence that some revision of acipenseriform classification may be needed to accurately inform conservation efforts and that future phylogenetic studies of this group should focus on the analysis of nuclear genes. [ABSTRACT FROM AUTHOR]

The article presents information on a study that determines how novel spotted fever group rickettsiae infecting amblyomma americanum ticks in Ohio. The main objective of the study is to determine the prevalence, species composition, and genetic diversity of tick borne rickettsiae found in amblyomma americanum ticks in Ohio. Researchers in the study finds a high rate of occurrence of rickettsiae amblyommii in amblyomma ticks from Ohio.

Summary Nuclear 18S ribosomal RNA (rRNA) gene sequences were determined during a phylogenetic study of the evolutionary relationships of the North American sturgeon and paddlefish. In the course of this study, intra-individual variation of the 18S rRNA gene was discovered in all nine species of sturgeon examined, while no variation was detected for this gene in the North American paddlefish (Polyodon spathula ) or in other non-acipenseriform fish species included in the study (bichirs, reedfish, gar, bowfin and lungfish). The discovery of multiple sequence variants of the 18S rRNA gene in an individual is unexpected; although most eukaryotes possess many copies of the rDNA unit in their genomes, the copies are normally thought to be homogenized within an individual as well as in a species by concerted evolution. The effect of the variation on the determination of species level relationships within the order and of the relationship of the order to other fish groups is examined. The actual cause(s) for the presence of intra-individual variation of the 18S rRNA gene are as yet unknown, however, it is possible that the origin and maintenance of multiple 18S rDNA sequence variants in sturgeon may be related to the polyploid status of the sturgeon genome. [ABSTRACT FROM AUTHOR]

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The article presents information on strain identification of Actinobacillus actinomycetemcomitans using the polymerase chain reaction. A definitive assay that can distinguish among strains of Actinobacillus actinomycetemcomitans is needed to track the transmission of bacterial strains within human populations to determine the mode of acquisition of this pathogen and to study the pathogenicity of specific strains. Molecular techniques can provide more precise methods of strain identification, and whole genomic DNA has been examined for restriction fragment length polymorphisms that have proved to have some utility in differentiating genetically distinct groups of oral microbes.