Effect of Environment and Genotype on Durum Wheat Gluten Strength and Pasta Viscoelasticity

Data on the quality of durum wheat genotypes grown under eight environments (site-year combinations) were evaluated to determine the relative effects of genotype and environment on quality characteristics associated with gluten strength, protein content, and pasta texture. The 10 durum wheat genotypes assessed in this study represented a range of gluten strength types from the very strong U.S. desert durum genotype, Durex, to the medium strength Canadian genotype, Plenty. Considerable genetic variability was detected for all quality characteristics studied. Genotype-environment interaction was significant for all quality parameters evaluated, with the exception of mixograph development time. Genotypeenvironment interaction was most important in determining protein content and least important in determining gluten index, gluten viscoelasticity, and SDS sedimentation volume. The nature of the genotype-environment interaction was evaluated by determining the number of significant crossover (rank change) interactions. There was at least one significant crossover interaction between pairs of genotypes and environments for five of eight quality traits tested. Of 45 genotype pairs, eight and six showed significant crossover interactions for protein content and pasta disk viscoelasticity, respectively. Significant crossover interactions were at least partially due to the differential response of Canadian genotypes as compared with U.S. genotypes. With the exception of protein content and pasta disk viscoelasticity, our results suggest that among the selected sample of 10 genotypes, genotype-environment interactions were minor and due primarily to changes in magnitude rather than changes in rank.     

Impact of Genotype and Environment on the Quality of Amber Durum Wheat Alkaline Noodles

Canada Western Amber Durum wheat cultivars (4), Canada Western Red Spring (1), and Canada Western Hard White Spring (1) wheat were grown at three sites in 2007 to evaluate the effect of genotype (G) and environment (E) on the quality of yellow alkaline noodles (YAN). YAN were evaluated for color, appearance, and cooked texture. Brightness (L*) and yellowness (b*) of YAN made from durum cultivars were significantly higher than common wheat. Durum flour yellow pigment content was approximately fourfold greater than common wheat while noodle speckiness was approximately half of CWRS at 2 hr with environment accounting for >75% of the variance for each parameter. Resistance to compression (RTC) and recovery (REC) of cooked durum alkaline noodles were equivalent or superior to common wheat noodles even when lower grade durum wheat flour was used. In conclusion, cooked durum noodle texture parameters were all significantly influenced by genotype and environment, with environment accounting for 66–71% of their variance.     

Phenolic Content and Antioxidant Properties of Bran in 51 Wheat Cultivars

Whole‐grain‐based diets have been suggested to reduce the incidence of cardiovascular disease and colon cancer. Phenolic compounds, most of which are present in the wheat bran, may be one of the factors contributing to whole‐grain health benefits. We measured the free, bound, and total phenolic content and antioxidant activity in the bran of 51 wheat cultivars belonging to eight Western Canadian spring wheat market classes grown in a replicated trial at Saskatoon, Saskatchewan, Canada. The free phenolic (extracted with 80% v/v aqueous ethanol) content ranged from 854.1 ± 265.1 to 1,754.9 ± 240.3 μg/g of bran gallic acid equivalent (GAE). Saponification followed by a liquid‐liquid solvent extraction released bound phenols ranging from 2,304.9 ± 483.0 to 5,386.1 ± 927.5 μg/g of bran GAE, contributing 66–82% of the total wheat bran phenolic content. Total phenolic content ranged from 3,406.4 ± 32.3 to 6,702.7 ± 19.6 μg/g of bran GAE, with the average being 5,197.2 ± 804.9 μg/g of bran GAE. Antioxidant activity ranged from 11.86 ± 2.59 to 20.12 ± 0.51%, while the overall average was 15.6 ± 2.2%. Based on varietal means, antioxidant activity correlated with free, bound, and total phenolic content (r = 0.8, P < 0.05).     

Genotype and Environment Affect Phytosterol Content and Composition of Wheat

Phytosterols (PS) lower low density lipoprotein (LDL) levels by as much as 10–14% in normal and hypercholesteromic people. High LDL levels in the blood are associated with an increased risk of coronary heart disease. Wheat germ and bran contain significant amounts of PS. The main objective of this study was to evaluate the effect of genotype and environment on PS content and composition in whole wheat grain. Protein and ash contents and mineral composition of the samples were also determined. Grain samples were collected from three cultivars, Jagger, Trego, and Intrada, grown at three locations, Alva, Balko, and Goodwell, OK in 2005. Irrigated and dryland samples were obtained from Goodwell. Total PS content and composition in the grain samples were determined using a gas chromatography system. Whole wheat grain samples varied in PS content from 202 mg/kg to 355 mg/kg. β‐Sitosterol, campesterol, and stigmasterol were the major PS compounds found in all the samples. PS exhibited a significant location‐by‐cultivar random effect (P < 0.048), indicating the presence of genotype‐by‐location interaction. Within each location, a significant cultivar effect was also observed. Protein and ash contents and mineral composition of the samples, except those collected from Goodwell‐dryland, were within the range published in the literature for other wheat cultivars. A fundamental understanding of compositional variation in wheat grain requires multi‐environment testing of genotypes, perhaps over several years. This study is a first step for achieving this goal.     

Influence of Durum Genotype on Whole Wheat and Traditional Spaghetti Qualities

This research was conducted to determine if genotypes selected for their superior traditional semolina pasta quality would also make the best whole wheat pasta. Results from 19 durum wheat cultivars and 17 breeding lines grown at 19 different environments in North Dakota showed that physical and cooking qualities varied differently for whole wheat and traditional spaghettis, respectively. Ward's clustering segregated the 36 genotypes into five groups based on whole wheat spaghetti quality. Groups 1 and 2 (21 genotypes) produced good to high‐quality whole wheat pasta that displayed high mean values for cooked firmness (4.3 and 4.1 g·cm), mechanical strength (31.3 and 31.0 g), and color (brightness, 34.92 and 34.54), respectively. Groups 4 and 5 produced poor quality whole wheat pasta that had low cooked firmness (both 3.5 g·cm) and high cooking loss (10.1 and 10.4%). Grain protein content (≥13.9%) was found with high quality of whole wheat spaghetti. Of the 36 genotypes evaluated, 21 and 3 genotypes produced good and poor qualities, respectively, of whole wheat and traditional spaghettis, and 12 other genotypes produced good traditional spaghetti but produced poor quality whole wheat spaghetti. These data indicate the need to select genotypes specifically for their whole wheat pasta quality.     

Influence of UV Exposure on Phenolic Acid Content,Mechanical Properties of Bran,and Milling Behavior of Durum Wheat (Triticum Durum Desf.)

Durum wheat bran was exposed to UV radiation up to 48 hr and the changes in ferulic acid (FA) content in the peripheral part s of grain were measured. The treatment resulted in a 25% decrease in FA monomer and a 44% decrease in dehydrodiferulic acid (DHD) ester‐linked to the cell‐wall arabinoxylans. This reduction was partly explained by a significant increase of FA (30%) and DHD (36%) engaged in hot alkali‐labile linkages. The results suggest that UV irradiation induced the formation of new cross‐links between feruloylated arabinoxylan and lignin in the pericarp. The effects of UV treatment on bran mechanical properties and wheat milling behavior were investigated. UV irradiation for 15 hr increased the stress to rupture by 30% and decreased the extensibility of bran tissues by 54%. This stiffening was associated with an increase in bran friability during grinding. Although this effect was due in part to the hydrothermal history of the grain, chemical modification induced by UV significantly influenced the size reduction of bran particles, which can be explained by the modification of the mechanical properties of bran. Relationships between the organization of cell‐wall polymers, the mechanical properties of tissues, and the behavior of wheat grain during milling were investigated.     

Phenolic Content and Antioxidant Activity of Pearled Wheat and Roller‐Milled Fractions

Wheat contains phenolic compounds concentrated mainly in bran tissues. This study examined the distribution of phenolics and antioxidant activities in wheat fractions derived from pearling and roller milling. Debranning (pearling) of wheat before milling is becoming increasingly accepted by the milling industry as a means of improving wheat rollermilling performance, making it of interest to determine the concentration of ferulic acid at various degrees of pearling. Eight cultivar samples were used, including five genotypes representing four commercial Canadian wheat classes with different intrinsic qualities. Wheat was pearled incrementally to obtain five fractions, each representing an amount of product equivalent to 5% of initial sample weight. Wheat was also roller milled without debranning. Total phenolic content of fractions was determined using the modified Folin‐Ciocalteau method for all pearling fractions, and for bran, shorts, bran flour, and first middlings flour from roller milling. Antioxidant activity was determined on phenolic extracts by a method involving the use of the free radical 2,2‐diphenyl‐l‐picrylhydrazyl (DPPH). Total phenolics were concentrated in fractions from the first and second pearlings (>4,000 mg/kg). Wheat fractions from the third and fourth pearlings still contained high phenolic content (>3,000 mg/kg). A similar trend was observed in antioxidant activity of the milled fractions with ≈4,000 mg/kg in bran and shorts, ≈3,000 mg/kg in bran flour, and <1,000 mg/kg in first middlings flour. Total phenolic content and antioxidant activity were highly correlated (R² = 0.94). There were no significant differences between red and white wheat samples. A strong influence of environment (growing location) was indicated. Pearling represents an effective technique to obtain wheat bran fractions enriched in phenolics and antioxidants, thereby maximizing health benefits associated with wheat‐based products.     

Total Phenolic Content and Antioxidant Capacity of Germinated,Popped, and Cooked Huauzontle (Chenopodium berlandieri spp. nuttalliae) Seeds

Raw, germinated, popped, and cooked huauzontle (Chenopodium berlandieri spp. nuttalliae) seeds were analyzed for the contents of phenolics extracted with water (WE), methanol, 1:1 (v/v) methanol/water (MWE), and 1.2M HCl in 1:1 (v/v) methanol/water (HMWE); radical scavenging capacity measured by the 2,2‐diphenyl‐1‐picrylhydrazyl (DPPH) and 2,2′‐azino‐bis(3‐ethylbenzothiazoline‐6‐sulphonic acid) (ABTS) methods was studied. The effect of the system solvents used for the accurate quantification of antioxidant content and capacity showed that for raw, germinated, and cooked extracts, water gave the highest yield of total phenolic content, and MWE could recover the highest yield in popped extracts. Thermal treatments increased the flavonoid content more in all extracts than did the germinating process, with values ranging from 10 to 620 μg/g db of quercetin equivalents. However, all treatments significantly decreased (P < 0.05) the total phenolics (from 3,010 μg of gallic acid equivalents/g db in raw seeds WE to 710 μg/g db in germinated seeds MWE). HMWE in all treatments showed the highest values (up to 95.41%) by the DPPH method. With the ABTS method, germinated and popped MWE showed the highest values (up to 2,740mM Trolox/kg db). Based on these results, huauzontle seeds represent a useful potential ingredient for consumer health, because it has been shown to be a good source of total phenolic content having high antioxidant activity; moreover, for further studies, water appears to be effective as an extraction solvent of phenolic compounds.     

Mineral Element and Total Phenolic Composition and Antioxidant Capacity of Seeds and Aerial Plant Parts of Perennial Legumes

ABSTRACT

Naturally derived bioactive compounds with antioxidant activity and mineral component have a positive effect on human health. Consequently, legumes, including perennial species, have been used as healthy food or medicinal plants. Red clover (Trifolium pratense) and lucerne (Medicago sativa) have been researched more thoroughly for food components and supplements than zigzag clover (T. medium), black medick (M. lupulina), liquorice milkvetch (Astragalus glycyphyllos), cicer milkvetch (A. cicer), and sainfoin (Onobrychis viciifolia). However, information is scarce about the distribution of mineral elements and phenolics in plants of these species as well as the antioxidant capacity of their extracts. In this study, we determined the mineral composition and total phenolic concentration in seeds and whole aerial plant parts and morphological fractions of these perennial legumes, as well as the antioxidant activity of extracts of the above-mentioned plant parts. The legume accessions chosen for this study were rich in potassium (K), calcium (Ca), magnesium (Mg), phosphorus (P), zinc (Zn), and iron (Fe), especially at branching growth stage, and thus could be used for mineral fortification of staple foods. Astragalus species, particularly seeds of A. glycyphyllos, were the richest source of Fe. Trifolium pratense, T. medium, O. viciifolia, and A. cicer were valuable source of total phenolics and antioxidants. The flower and leaf extracts of red clover exhibited very strong 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging activity. In general, the tested perennial legumes and their plant parts have rich mineral composition and bioactive properties, and they can be used as functional ingredients to accommodate the need for a particular mineral element or a bioactive property.     

Effects of Salinity and Drought Stress on Grain Quality of Durum Wheat

This work aimed to assess the influences of soil salinity and drought stresses on grain quality characteristics of selected salt-tolerant genotypes differing in salinity tolerance in durum wheat. This study was conducted under control, drought, and saline field conditions in separate experiments during 2 years. A randomized complete block design with three replications was used for each experiment. The results showed significant effects of genotype and environmental conditions on all grain-quality related traits. Salt and drought stress caused the significant increment of grain protein content, wet and dry gluten contents, and sodium dodecyl sulfate (SDS) sedimentation volume. Thousand-grain weight, grain protein yield, and test weight reduced significantly under both salinity and drought stress conditions. Protein content showed positive correlation with wet gluten, dry gluten, SDS sedimentation, and volume and strong negative correlation with other traits. It is concluded that influence of salinity stress was greater than drought stress on grain protein yield and some other grain-quality-related traits.     

A Comprehensive Genotype and Environment Assessment of Wheat Grain Ash Content in Oregon and Washington: Analysis of Variation

A comprehensive analysis of the variation in wheat grain ash content has not been previously conducted. This study assessed the relative contribution of genotype and environment to variation in ash content, with a particular aim of ascertaining the potential for manipulating the trait using contemporary adapted germplasm. A total of 2,240 samples were drawn from four years of multilocation field plots grown in the wheat production areas of Oregon and Washington states. Genotypes included commercial cultivars and advanced breeding lines of soft and hard winter, and soft and hard spring wheats with red and white kernel color, several soft white club wheats, and one soft white spring waxy wheat cultivar. In addition to ash, protein content, test weight, and Single Kernel Characterization System kernel hardness, weight and size were also measured. In total, 20 separate fully balanced ANOVA results were conducted. Whole model R² values were highly significant, 0.62–0.91. Nineteen of the 20 ANOVA results indicated significant genotype effects, but the effects were not large. In contrast, environment effects were always highly significant with F values often one to two orders of magnitude larger than the genotype F values. The grand mean for all samples was 1.368% ash. For individual data sets, genotype means across environments varied ≈0.1–0.3% ash. The genotypes judged noteworthy because they had the highest least squares mean ash content were OR9900553 and ClearFirst soft white winter, NuHills hard red winter, Waxy‐Pen and Cataldo soft white spring, and WA8010 and Lochsa hard spring wheats. Genotypes with lowest least squares mean ash were Edwin (club) soft white winter, OR2040073H hard red winter, WA7952 soft white spring, and WA8038 hard spring wheats. In conclusion, wheat grain ash is more greatly influenced by crop year and location than by genotype. However, sufficient genotype variation is present to plausibly manipulate this grain trait through traditional plant breeding.     

Phenolic Fingerprint of Sicilian Modern Cultivars and Durum Wheat Landraces: A Tool to Assess Biodiversity

Durum wheat landraces have been recognized to have different contents in health‐promoting phytochemicals. These health benefits have been mainly attributed to the presence of phenolic acids and flavonoids existing in this matrix both as soluble free compounds and insoluble bound forms. Sicily is one of the few areas of Southern Europe where it is still possible to find landraces of durum wheat, no longer cropped because of the commercial spread of new high‐yielding varieties. This study aimed to determine the phenolic profile and content of 10 wheat landraces and three genetically improved cultivars to develop an analytical tool for cultivar screening and traceability. Hydroalcoholic extracts from wheat grains were analyzed by means of HPLC with a diode‐array detector and HPLC electrospray ionization MS, revealing 13 metabolites belonging mainly to the classes of hydroxycinnamic acids and flavones C‐glycosides. The quantitative pattern of the 13 phenolic markers, analyzed by applying stepwise linear discriminant analysis, allowed the discrimination between the two groups under study, namely, modern cultivars and durum wheat landraces. Furthermore, all 13 durum wheat varieties were perfectly discriminated in this statistical model, confirming a specific and genotype‐dependent pattern of phenolics concentration.     

Genotype and Environment Effects on Wheat Quality Traits in a Population Derived from a Soft by Hard Cross

Advances in understanding the biochemistry and genetics underlying wheat end-use quality require that cereal chemistry research utilize lines grown in the same environments. It also requires that effects of linkage disequilibrium and small ranges in trait variation be avoided. Our objectives were to: 1) ascertain the effects of genotype and environment and their interactions on hard and soft wheat end-use quality traits, and 2) examine relationships between traits and heritability, using recombinant inbred lines derived from a soft by hard wheat cross. All traits showed transgressive segregation. Kernel texture (KT) was not genetically correlated with mixograph traits, indicating the feasibility of producing soft-textured genotypes with stronger mixing properties. KT was highly genetically correlated with alkaline water retention capacity (AWRC) and moderately genetically correlated with flour yield (FY). Protein content (PRO) was not genetically correlated with dough mixing time across lines, but was with dough mixing strength. KT, FY, and mixograph traits demonstrated higher heritabilities than did AWRC and PRO. Genotype and environment and their interactions affected all traits. Year caused the greatest environment effects, affecting primarily AWRC and PRO. Genotype affected mainly KT, FY, and peak time. The effect of environment on those traits supports the need to develop screening methods using genotype rather than phenotype.     

Simple Phenolic Acids in Flours Prepared from Canadian Wheat: Relationship to Ash Content,Color, and Polyphenol Oxidase Activity

Simple phenolic acid levels were determined on pooled millstreams of five different classes of Canadian wheat milled to ~75, 80, and 85% extraction. Pooled flours and whole grain were analyzed by reversed-phase high-performance liquid chromatography (RP-HPLC) to establish endogenous levels of insoluble bound, soluble esterified, and free phenolic acids. Only ferulic acid was detected in the insoluble bound category, which accounted for >80% of the total phenolic acids present in every flour. The soluble esterified phenolic acids accounted for up to 17% of the overall total phenolic acid content within a flour. The major constituents were sinapic, ferulic, and vanillic acids, with minor amounts of coumaric, caffeic, and syringic acids. Free phenolic acids accounted for a maximum of 6% of the total phenolic content of any prepared flour. Ferulic acid was the major free phenolic acid, while sinapic acid was not detected in any flour. Significant correlations (r = 0.64–0.97, P < 0.05) were observed between insoluble bound ferulic acid, individual soluble esterified acids, and most free acids with polyphenol oxidase activity, as well as color and ash content for each class.     

电解水对荞麦芽酚酸含量及抗氧化能力的影响

为了能够更好地将发芽荞麦用作制备功能食品的原料,本研究采用理化指标不同的电解水制备荞麦芽,考察荞麦的发芽率及芽长、总酚含量、DPPH和ABTS自由基清除能力,以及铁离子还原力在发芽期间的动态变化,并分析各处理组发芽第7天荞麦芽中游离酚和结合酚种类和含量。结果表明,在7 d观测期内,电解水有利于荞麦发芽及生长。不同评价方法测定荞麦芽抗氧化能力的结果显示,pH值11.13电解水处理组发芽1~3 d荞麦芽总酚含量及抗氧化水平均显著高于对照组(P<0.05),而pH值3.21、pH值5.02和pH值9.02电解水处理组发芽5~7 d荞麦芽总酚含量及抗氧化水平均显著高于对照组(P<0.05)。各处理组荞麦芽中主要的游离酚均为绿原酸,且电解水处理组荞麦芽游离绿原酸含量均显著高于对照组(P<0.05)。自来水处理组荞麦芽主要结合酚为香豆酸,而电解水处理组荞麦芽主要结合酚为咖啡酸。本研究结果为电解水应用于功能性荞麦芽的制备提供了理论依据。     

Effect of Wheat Genotype and Environment on Relationships Between Dough Extensibility and Breadmaking Quality

Dough extensibility affects processing ease, gas retention, and loaf volume of finished products. The Kieffer dough extensibility test was developed to assess extensibility of small dough samples and is therefore adapted for use in breeding programs. Information is lacking on relationships between wheat growing environments and dough properties measured by the Kieffer dough extensibility test. This study documents the variability of dough extensibility (Ext), maximum resistance to extension (Rmax), and area under the extensibility curve (Area) in relation to breadmaking quality, and the effect of wheat growing environments. Mixograph, Kieffer dough extensibility, and bake tests were performed on flour milled from 19 hard red spring wheat (Triticum aestivum L.) genotypes grown during three growing seasons (2007‐2009) at six South Dakota locations. Although both genotype and environment had significant effects on Kieffer dough extensibility variables, environment represented the largest source of variation. Among genotype means, Area was most correlated (r = 0.63) with loaf volume, suggesting that by selecting lines with increased Area, loaf volume should improve. Rmax was positively correlated (r = 0.58) with loaf volume among genotype means but negatively correlated (r = –0.80) among environmental means. Ext was positively correlated (r = 0.90) with loaf volume among environmental means. Weather variables were correlated with Rmax, Ext and loaf volume and therefore could help predict end‐use quality.     

Phenolic Content,Antioxidant Activity,and Consumer Acceptability of Sorghum Cookies

Cookies were produced from different sorghum flours to determine their potential as vectors of antioxidants. Different sorghum cultivars and their flour extraction rates were evaluated for their effects on phenolic content and antioxidant activity of the cookies. Consumer acceptance of the sorghum cookies was compared with that of wheat flour cookies. For each sorghum cultivar, cookies of 100% extraction rate flours had two to three times more total phenolics compared with those of 70% extraction rate flours, while antioxidant activity was 22–90% higher. Cookies of the condensed tannin sorghum had two to five times more phenolics compared with those of condensed tannin‐free sorghum. Antioxidant activity was 145–227 μMol Trolox equivalents (TE)/g in cookies of condensed tannin sorghum compared with 10–102 μMol TE/g in those of condensed tannin‐free sorghum. The sorghum flours had slightly higher phenolic content and antioxidant activity values than their corresponding cookies. Cookies of the red tannin‐free sorghum flours (PAN 8564/8446) were equally liked as wheat flour cookies, except for texture. However, cookies of condensed tannin sorghum were least accepted compared with wheat flour cookies despite their high antioxidant activity.     

Antioxidant Activity and Phenolic Content of Air‐Classified Corn Bran

The effectiveness of extracting free and bound phenolic compounds and antioxidant activities from air‐classified corn bran was evaluated by various extracting methods. Free phenolic contents and antioxidant activities decreased significantly with increasing particle sizes for all methods used in the study. Also, the oil, protein, and ash contents were noticeably decreased with increasing particle sizes. By contrast, bound phenolic content and antioxidant activities increased with increasing particle sizes. Free phenolic contents were much lower than those of bound phenolic contents for the same fraction. The free antioxidant activities were similar to bound antioxidant activities for the same fraction. It suggests that some phenolic compounds may not exhibit antioxidant activity, and some antioxidant activities were not extractable or released during alkaline extraction. Considerable higher free antioxidant activities were found in both direct and double extractions when compared to the single neutral extraction using samples <30 μm. Similar free antioxidant activities were observed for directed extraction and double extraction. For corn bran fractions, the direct method may be suitable for free phenolic content and antioxidant activity, while the sequential method may be proper for bound phenolic content and antioxidant activity.     

Effects of Nitrogen and Sulfur Fertilizers on Gliadin Composition of Several Cultivars of Durum Wheat

Four fertilizer treatments were applied to 10 cultivars of durum wheat (Triticum turgidum var. durum L.) in three seasons of designed field trials. The fertilizer treatments were N0S0 ‐ neither N nor S applied; N1S0 ‐ only N applied; N1S1 ‐ both N and S applied; N0S1 ‐ only S applied. It was found, through densitometric SDS‐PAGE, that the relative proportion of different gliadin components was influenced by the distinct regimes, even though our region in the center of the Argentinean Pampa is not considered to be deficient in soil S‐availability. The effects observed were more marked in one particular season of the three studied, were principally associated with the treatment expected to produce the maximum degree of grain S‐deficiency (N1S0), and were consistent with the hypothesis that the relative content of S‐poor gliadins increases under conditions of S‐deficiency, as has been found in related crops. Multivariate reverse‐phase high‐performance liquid chromatography (RP‐HPLC) analysis of samples from the season most affected generally supported these observations, but refined them in identifying quantitative differences between all four fertilizer treatments for the cultivars studied. These findings imply that differences in industrial quality might also be expected between the fertilizer treatments. RP‐HPLC also identified numerous genetically controlled qualitative differences in the gliadins between the cultivars studied, adding to previous published work on these cultivars based on SDS‐PAGE. These observations confirmed that one particular cultivar of very low gluten strength showed a gliadin profile markedly distinct from the remaining cultivars studied.     

The Effect of Bioprocessing on the Phenolic Acid Composition and Antioxidant Activity of Wheat Bran

In the present study, bioprocessing with eight microbial strains including Bacillus species, yeasts, and filamentous fungi was evaluated for its potential to improve the phenolic acid composition and antioxidant activity of wheat bran. The soluble free and soluble conjugated fractions of ethanolic extracts of the treated bran samples were compared for their total phenolic contents, phenolic acid composition, and in vitro antioxidant activities. In general, total phenolic content in the soluble free fraction increased significantly, accounting for 241.11 ± 1.25 μg of gallic acid equivalents (GE)/g (Rhizopus oryzae), 230.50 ± 1.05 μg of GE/g (Mucor circinelloides), and 230.19 ± 1.02 μg of GE/g (Saccharomycopsis fibuligera). The phenolic acid composition, especially of the soluble free fraction, was improved most by S. fibuligera (hydroxybenzoic, vanillic, syringic, and trans‐ferulic acids), M. circinelloides (chlorogenic acid), and R. oryzae (protocatechuic, trans‐coumaric, and benzoic acids). Comparatively, bioprocessing exhibited less effectiveness on conjugated phenolic acid composition. Fermented wheat bran displayed enhanced reducing capacity, superoxide anion radical scavenging activity, and 1,1‐diphenyl‐2‐picrylhydrazyl radical scavenging activity in comparison with the nonfermented sample. The antioxidant activity was significantly correlated to the total phenolic content.