The Relationship Between D Hordein and Malting Quality in Barley

The contribution of grain protein to the malting quality of barley (Hordeum vulgareL.) was investigated by comparing the hordein composition and the malting quality in barley produced under a range of field conditions. Two malting cultivars, Schooner and Arapiles, and one feed cultivar, Galleon, were grown under five nitrogen regimes in each of two years. Hordein composition of the grain was determined at maturity using a combination of sodium dodecyl sulphate-polacrylamide gel electrophoresis and laser densitometry. Malt extract was determined on all samples after micromalting. Variation in growth conditions resulted in a wide range of grain protein contents and malt extract values, as well as variation in the proportions of the individual B, C and D hordeins in the grain. D hordein in particular varied over a 10-fold range. High levels of all protein fractions were associated with low malt extract. Total protein, as expected, displayed a strong, negative correlation with malt extract. The relationship was cultivar specific and separate regression lines were generated for each cultivar. Of the individual hordein fractions, D hordein displayed the strongest negative correlation with malt extract and its relationship to malt extract was independent of cultivar. A consistent relationship between D hordein and malt extract was observed across seasons, treatments and cultivars that was indicative of a causal relationship between D hordein and malting quality. D hordein therefore offers an alternative measurement to total protein for the prediction of malting quality over a wide range of environmental conditions and cultivars.     

Ferulic and p-coumaric acids extraction by alkaline hydrolysis of brewer's spent grain

This work deals with the alkaline hydrolysis of brewer's spent grain (BSG) for the extraction of ferulic and p-coumaric acids, compounds of considerable interest for applications in the food, health, cosmetic, and pharmaceutical industries. A 2³ full factorial design with three replicates at the center point was used to investigate the simultaneous effects of the variables: NaOH concentration (1.0, 1.5 and 2.0%, w/v), temperature (80, 100 and 120 °C), and reaction time (30, 60 and 90 min), on the alkaline hydrolysis. The assays were performed using a solid:liquid ratio of 1:20 (w/w). The Student's t-test revealed a positive influence (p < 0.05) of all the studied variables on the ferulic and p-coumaric acids extraction from BSG. Linear models were well fitted (R² > 0.90) to the experimental data to describe the extraction of these acids as a function of the operational variables employed. The best alkaline hydrolysis conditions consisted in using a 2% NaOH concentration, at 120 °C for 90 min. Under these conditions, a liquor containing 145.3 mg/l ferulic acid and 138.8 mg/l p-coumaric acid was obtained. These values corresponded to 9.65 mg ferulic acid and 9.22 mg p-coumaric acid per gram of solubilized lignin.     

Impact of redox agents on the physico-chemistry of wheat gluten proteins during hydrothermal treatment

The impact of the oxidants potassium bromate and potassium iodate and the reducing agent dithiothreitol (DTT) on the rheological behaviour of 20% (w/v) gluten-in-water suspensions during thermal treatment was monitored with the rapid visco analyser (RVA). The suspensions were subjected to a linear temperature increase from 40 to 95 °C in 14 min, a holding step of 40 min at 95 °C, a cooling step (7 min) with a linear temperature decrease to 50 °C, and a final holding step at 50 °C (13 min). Potassium iodate (1.18 and 1.77 μmol/g protein) and potassium bromate (1.52 and 15.2 μmol/g protein) decreased RVA viscosities in the holding step and increased sodium dodecyl sulphate (SDS) protein extractabilities suggesting a greater heat resistance and decreased gliadin–glutenin cross-linking. In contrast, in the presence of DTT (1.65 and 3.30 μmol/g protein) RVA viscosity increased at lower temperatures and lowered SDS extractabilities. It is postulated that low concentrations of reducing agent facilitate gliadin–glutenin cross-linking during heating while oxidants hinder gluten polymerization due to decreased levels of free sulphydryl groups and less flexibility of the glutenin chains.     

Interspecific competition,N use and interference with weeds in pea–barley intercropping

Field pea (Pisum sativum L.) and spring barley (Hordeum vulgare L.) were intercropped and sole cropped to compare the effects of crop diversity on productivity and use of N sources on a soil with a high weed pressure. ¹⁵N enrichment techniques were used to determine the pea–barley–weed-N dynamics. The pea–barley intercrop yielded 4.6 t grain ha⁻¹, which was significantly greater than the yields of pea and barley in sole cropping. Calculation of land equivalent ratios showed that plant growth factors were used from 25 to 38% more efficiently by the intercrop than by the sole crops. Barley sole crops accumulated 65 kg soil N ha⁻¹ in aboveground plant parts, which was similar to 73 kg soil N ha⁻¹ in the pea–barley intercrop and significantly greater than 15 kg soil N ha⁻¹ in the pea sole crop. The weeds accumulated 57 kg soil N ha⁻¹ in aboveground plant parts during the growing season in the pea sole crops. Intercropped barley accumulated 71 kg N ha⁻¹. Pea relied on N₂ fixation with 90–95% of aboveground N accumulation derived from N₂ fixation independent of cropping system. Pea grown in intercrop with barley instead of sole crop had greater competitive ability towards weeds and soil inorganic N was consequently used for barley grain production instead of weed biomass. There was no indication of a greater inorganic N content after pea compared to barley or pea–barley. However, 46 days after emergence there was about 30 kg N ha⁻¹ inorganic N more under the pea sole crop than under the other two crops. Such greater inorganic N levels during early growth phases was assumed to induce aggressive weed populations and interspecific competition. Pea–barley intercropping seems to be a promising practice of protein production in cropping systems with high weed pressures and low levels of available N.     

Antioxidative properties of partially purified barley hordein, rice bran protein fractions and their hydrolysates

Antioxidative properties of proteins from barley and rice bran and their hydrolysates were examined. Three major hordein fractions of barley, B, C and D hordeins, were partially purified by gel filtration. Albumin, globulin, prolamin and glutelin fractions of rice bran were fractioned by the Osborne method. Hydrolysates of these protein fractions were prepared by digesting with pepsin followed by trypsin. Antioxidant properties in terms of antioxidative activity against linoleic acid peroxidation and reducing activity without the lipid adjuvant were investigated. The globulin fraction from rice bran protein revealed the strongest antioxidative activity throughout the incubation time of 7 days (p ≤ 0.05). The albumin fraction of rice bran protein showed the highest reducing activity (6964 μmol of Fe²⁺) followed by globulin, prolamin, glutelin and hordein fractions with activities of 2904, 2017, 1809 and 1333 μmol of Fe²⁺, respectively (p ≤ 0.05). Partially purified C hordein exhibited the highest reducing activity compared with B and D hordeins. Protein hydrolysates obtained after digestion with pepsin and trypsin exhibited much greater antioxidative, as well as reducing, activities than those from before digestion.     

Digestion of barley malt porridges in a gastrointestinal model: Iron dialysability,iron uptake by Caco-2 cells and degradation of β-glucan

Iron availability and degradation of (1→3,1→4)-β-d-glucan (β-glucan) in three whole grain porridges made from two optimised barley malts and unprocessed barley were studied in a dynamic gastrointestinal model. The malting processes, with steeping at 15 or 48 °C with lactic acid (LA), enabled a complete reduction of phytate by subsequent soaking of ground malt, still with well preserved β-glucan. Iron dialysability and iron uptake by Caco-2 cells were higher in phytate reduced porridges, compared to the reference porridge. During simulated digestion, the extractability of β-glucan increased and the Calcofluor average molecular weight decreased for all porridges, indicating a gradual degradation during passage through the model. The degradation rate, however, appeared lower in porridge prepared from malted barley steeped at 48 °C with LA. The gastrointestinal model ranked iron availability according to human absorption data and showed high repeatability when evaluating changes in β-glucan. The results indicate the potential for using high temperature steeping with LA to yield improved iron availability combined with reduced degradation of β-glucan in the small intestine, maintaining the beneficial properties of barley.     

Net blotch in semi-arid regions of Morocco II

Net blotch incited by Pyrenophora teres f. teres is an important constraint for barley production in the semi-arid regions of Morocco, reaching epidemic proportions under favorable weather conditions. In this study, we generated 480 epidemics. These epidemics were characterized at five sites and for six different varieties with plants either inoculated by the pathogen or treated with fungicide tilt (propiconazle) 250 a.i. ha⁻¹. The study was conducted in two growing seasons (1995–1996 and 1996–1997). Disease severity and area under the disease progress curve (AUDPC) were related to grain yield. Critical-point model (CPM) and multiple-point model (MPM) did not explain the yield variability encountered and were not investigated further. For the same reason, the relationship between the AUDPC and yield was discarded. Disease effect on yield loss was closely related to yield potential in each growing season, and could not be used to predict yield or yield losses. Estimated yield losses due to net blotch varied between 14 and 29% with resistant varieties out yielding susceptible varieties by 39% when there was no disease control and by 56% under fungicide treatment. Varietal resistance is essential to the control of barley net blotch. A response surface model based on grain yield, AUDPC and growth stage explained most of the yield variability (R²=0.94). This model was validated with 13 barley varieties and two mixtures. The fitting of this response surface model predicted grain yields within ±200 kg ha⁻¹ when tested from booting to flowering stages.     

Preparation of biodiesel from Idesia polycarpa var. vestita fruit oil

The feasibility of producing biodiesel from Idesia polycarpa var. vestita fruit oil was studied. A methyl ester biodiesel was prepared from refined I. polycarpa fruit oil using methanol and potassium hydroxide (KOH) in an alkali-catalyzed transesterification process. The experimental variables investigated in this study were catalyst concentration (0.5–2.0 wt.% of oil), methanol/oil molar ratio (4.5:1 to 6.5:1), temperature (20–60 °C) and reaction time (20–60 min). A maximum yield of over 99% of methyl esters in I. polycarpa fruit oil biodiesel was achieved using a 6:1 molar ratio of methanol to oil, 1.0% KOH (% oil) and reaction time for 40 min at 30 °C. The properties of I. polycarpa fruit oil methyl esters produced under optimum conditions were also analyzed for specifications for biodiesel as fuel in diesel engines according to China Biofuel Systems Standards. The fuel properties of the I. polycarpa fruit oil biodiesel obtained are similar to the No. 0 light diesel fuel and most of the parameters comply with the limits established by specifications for biodiesel.     

Soil quality responses to alfalfa watered with a field micro-catchment technique in the Loess Plateau of China

This paper explores the soil responses to alfalfa that is established using a field micro-catchment technique to harvest water under semiarid conditions. The field micro-catchment technique involved setting up ridges and furrows alternately on the flat land. The ridges served as the rainfall harvesting zone and the furrows as the planting zone. Five treatments were set up in this study: (1) conventional cultivation in a flat plot without mulch (CK), (2) plastic mulched ridge with 30 cm width of ridge and furrow (M30), (3) plastic mulched ridge with 60 cm width of ridge and furrow (M60), (4) bare ridge with 30 cm width of ridge and furrow (B30), (5) bare ridge with 60 cm width of ridge and furrow (B60). The mulching treatments increased the productivity of seeded alfalfa and significantly (p < 0.05) increased water use efficiency, causing the soil organic carbon (SOC), total soil nitrogen (TSN) and C/N ratio to increase. We also found that the alfalfa root system was very good at breaking up the plowing pan created by many years of tillage. In the M30 and M60 treatments, the total forage yield during the 3 years was higher than in CK by 10.7% and 40.3% respectively, whereas the total forage yield over the 3 years in the B30 and B60 treatments were lower than in the CK treatment by 14.2% and 28.3%, respectively. The water use efficiency in the mulching treatment was significantly higher than in the other treatments. After 3 years (2001–2003), the SOC content in ridge and furrow treatments (M30, M60, B30 and B60) was increased by 7.4%, 14.2%, 4.5% and 1.8%, respectively, contrasting with a decrease of 3.5% in the CK treatment. The increase in SOC positively correlated (R² = 0.6257) with the forage yield of alfalfa in the ridge and furrow treatments. The TSN for CK, M30, M60, B30 and B60 increased by 0.35%, 1.70%, 2.30%, 0.75% and 0.64%, respectively by the end of the 3 years. However, we found that the available phosphorus (P) in the mulch treatments during the 3-year period decreased rapidly indicating that it is necessary to apply P fertilizer to alfalfa-cultivated land under these management conditions. In conclusion, the ridge and furrow with mulch treatments, especially M60 treatments, proved to be a better pattern for alfalfa establishment, soil quality and nutrient cycling under semiarid conditions.     

Reduction of phytate content while preserving minerals during whole grain cereal tempe fermentation

The effects of different pretreatments on phytate and mineral contents were investigated in whole grain barley and oat tempe fermented with Rhizopus oligosporus. Different varieties of barley and oats were exposed to pretreatments such as pearling, rolling, moistening, autoclaving and soaking before fermentation. Pearling was the most effective pretreatment for reduction of phytate content for both oats and barley. Nevertheless, mineral contents were reduced, and most likely cell wall rich fractions were also reduced by this process. In the first experiments the phytate content reduction in the oats and barley samples were reduced by 74% (3.3 μmol/g, d.m.) and 89% (1.4 μmol/g, d.m.), respectively. However, to improve iron absorption the phytate levels should not exceed 0.5 μmol/g, and further phytate degradation was necessary. Therefore, in the final experiments barley samples were exposed to an optimised process with prolonged soaking at a higher temperature and the pearling residues were returned before fermentation. When the outer layers of the barley kernels were returned before fermentation the phytate content was successfully reduced by 97% to 0.4 μmol/g (d.m.) and Fe and Zn levels were well preserved.     

Effect of SWD irrigation on photosynthesis and grain yield of rice (Oryza sativa L.)

A study was conducted with the objective to determine the influence of (shallow water depth with wetting and drying) SWD on leaf photosynthesis of rice plants under field conditions. Experiments using SWD and traditional irrigations (TRI) were carried out at three transplanting densities, namely D1 (7.5 plants/m²), D2 (13.5 plants/m²) and D3 (19.5 plants/m²) with or without the addition of organic manure (0 and 15 t/ha). A significant increase in leaf net photosynthetic rate by SWD was observed with portable photosynthesis systems in two independent experiments. At both flowering and 20 DAF stages, photosynthetic rate was increased by 14.8% and 33.2% with D2 compared to control. SWD significantly increased specific leaf weight by 17.0% and 11.8% over the control at flowering and 20 DAF stages, respectively. LAI of D2 under SWD was significantly increased by 57.4% at 20 DAF. In addition, SWD with D2 significantly increased the leaf dry weight (DW) at both growing stages. At all the three densities, SWD increased the leaf N content and the increase was 18.9% at D2 density compared with the conventional control. In SWD irrigation, the leaf net photosynthetic rate was positively correlated with the leaf N content (R² = 0.9413), and the stomatal conductance was also positively correlated with leaf N content (R² = 0.7359). SWD enhanced sink size by increasing both panicle number and spikelet number per panicle. The increase in spikelet number per panicle was more pronounced in the 15 t ha⁻¹ manure treatment than in the zero-manure treatment. Grain yield was also significantly increased by SWD, with an average increase of 10% across all treatments. SWD with D2 had the highest grain yield under the both cultivars with or without 15 t ha⁻¹ manure treatment, which was 14.7% or 13.9% increase for Liangyoupeijiu and 11.3% or 11.2% for Zhongyou 6 over the control, respectively.     

Extractability and chromatographic separation of rice endosperm proteins

The molecular weight (MW) distribution of proteins extracted with different solvents from defatted rice endosperm was examined by size exclusion-high performance liquid chromatography (SE-HPLC) with 2.0% sodium dodecyl sulfate (SDS) (w/v) as mobile phase. The resulting protein peaks were further characterized by SDS-PAGE. Under the experimental conditions, 2.0% SDS extracted 64% of the proteins. Adding 6.0 M urea resulted in a 15% increase in extractability (up to 79%). With using 20–100 mM NaOH, 70–81% of the proteins were extractable. Maximum extractability was reached with 2.0% SDS, 6.0 M urea and 0.5–1.5% dithiothreitol (DTT). Apparent MW profiles of rice endosperm proteins allowed classification into six fractions of decreasing apparent MW. Fraction VI contained the low MW albumin, globulin, and prolamin protein material. Fractions IV and V originated from α and β glutelin subunits, respectively. The polypeptides of fraction III consisted of an α and a β subunit linked by an intermolecular disulfide bond. The polypeptides of fractions I and II were dimers, trimers or more highly polymerized forms of the (α–β) glutelin subunit dimer in fraction III. While the work confirmed that rice glutelin is composed of polymers of α and β subunits, remarkably, higher MW glutelin aggregates (fractions I–III) only partly dissociated on reduction. Low MW protein material (fraction VI) was entrapped in the aggregated protein network and was released on reduction. The rapid and reproducible SE-HPLC method developed for rice protein separation allows a more quantitative approach than SDS-PAGE.     

Methyl jasmonate,alone or in combination with genistein,and Bradyrhizobium japonicum increases soybean (Glycine max L.) plant dry matter production and grain yield under short season conditions

Jasmonic acid (JA) is a plant hormone produced via the octadecanoid pathway from its precursor, linolenic acid. Jasmonates are involved in plant wound responses and defense against insects and fungal elicitors. They can also act as signal molecules in the Bradyrhizobium-soybean symbiosis. Pre-incubation of Bradyrhizobium japonicum inocula with gensitein (Ge), an effective inducer of nodulation genes in this species enhances soybean nodulation, nitrogen fixation and yield under low spring soil temperature field conditions. Since jasmonates are also able to induce nodulation genes and cause the production of lipo-chitooligosaccharides (LCOs) by B. japonicum, we conducted two field experiments, in southwestern Quebec, Canada, to determine whether pre-incubation of B. japonicum with methyl jasmonate (MeJA) alone or in combination with genistein (Ge), prior to inoculation, increased soybean plant dry matter production and grain yield. Experiments at each site used a two factor randomized complete block design (RCBD) with four replicates. Two B. japonicum strains (USDA3 and 532C) and four inducer molecule treatments [control, Ge (20 μM), MeJA (50 μM), and Ge + MeJA (20 μM + 50 μM)] were used in the study. The bacterial cultures were induced for 24 h with the inducer molecules and then applied into the furrows at the time of planting. Both Ge and MeJA, alone or in combination, increased plant growth, dry matter accumulation, and grain yield. This study showed that MeJA, alone or in combination with Ge, can be used to promote soybean plant growth and grain yield under short season field conditions.     

Differential accumulation of sulfur-rich and sulfur-poor wheat flour proteins is affected by temperature and mineral nutrition during grain development

Hard red spring wheat (Triticum aestivum cv Butte86) was grown under controlled environmental conditions and grain produced under 24/17 °C, 37/17 °C or 37/28 °C day/night regimens with or without post-anthesis N supplied as NPK. Flour proteins were analyzed and quantified by differential fractionation and RP-HPLC, and endosperm proteins were assessed by two-dimensional gel electrophoresis (2-DE). High temperature or NPK during grain fill increased protein percentage and altered the proportions of S-rich and S-poor proteins. Addition of NPK increased protein accumulation per grain under the 24/17 °C but not the 37/28 °C regimen. However, flour protein composition was similar for grain produced with NPK at 24/17 °C or 37/28 °C. 2-DE of gluten proteins during grain development revealed that NPK or high temperature increased the accumulation rate for S-poor proteins more than for S-rich proteins. Flour S content did not indicate S-deficiency, however, and addition of post-anthesis S had no effect on protein composition. Although, high-protein flour from grain produced under the 37/28 °C regimen with or without NPK had loaf volumes comparable to flour produced at 24/17 °C with NPK, mixing tolerance was decreased by the high temperature regimen.     

Bio-oil production from soybean (Glycine max L.); fuel properties of Bio-oil

Soybean oil cake (SOC) has been studied to produce bio-oil in a fixed-bed pyrolysis unit. The effect of pyrolysis parameters on the product yields and compositions were investigated. The highest bio-oil yield of a ca 25.8 wt.% was obtained at 400 °C pyrolysis temperature with a heating rate of 50 °C/min for particles of 0.425–0.600 mm in size. The various characteristics of bio-oil acquired under these conditions were identified. The empirical formula of bio-oil with a calorific value of 33.6 MJ/kg was established as CH_1.37O_0.15N_0.14. The chemical characterization studies showed that the bio-oil obtained from SOC might be a potentially valuable source as renewable fuel and chemical feedstocks.     

Thermal requirements for barley maturation and leaf development in interior Alaska

Spring barley (Hordeum vulgare L.) is well adapted to the cool and short growing season of interior Alaska but little is known about thermal requirements for development and maturation of barley at such latitudes. Air temperature and barley development were monitored over the course of six growing seasons at Fairbanks (65°N) and Delta Junction (64°N), Alaska. These data were used to assess the base temperature (T_b) in the linear, thermal-unit model using the least variable, x-intercept, and regression coefficient methods. These methods indicated a range in T_b from 0°C to 1.5°C. At a T_b of 0°C, barley required nearly 1100°C d to mature. The phyllochron differed between early and late sowings and averaged 75°C d leaf⁻¹. Sowing date appeared to influence the phyllochron during early vegetative growth due to differences in daylength as well as temperature.     

Developing rice cultivars for high-fertility upland systems in the Asian tropics

Traditionally, upland rice is grown in Asia in low-input, subsistence systems. More productive upland systems, using more fertilizer and improved varieties, are emerging in China and Philippines, and could contribute to productivity increases in rainfed environments in other countries. Here, we evaluate, on-station and on-farm, the yield under upland management of improved indica upland cultivars selected for yield under high-fertility conditions. These cultivars are compared with traditional and improved tropical japonica upland varieties, and with elite indica high-yielding varieties (HYV) developed for irrigated lowland production, to characterize the features of varieties that produce high yields in favorable upland environments. Forty-four improved and traditional varieties and experimental lines were evaluated in irrigated lowland, non-stressed upland, moderately stressed upland, severely water-stressed upland, and low-fertility upland environments in southern Luzon, Philippines. Correlations between yields in non-stress and mild-stress environments were low but positive. Some cultivars, like IR55423-01, were among the highest yielding under both conditions, indicating that high yield and moderate water-stress tolerance can be combined. Upland-selected indica varieties yielded 3.56 t ha⁻¹ in favorable upland environments on-station in southern Luzon, outperforming improved tropical japonica and irrigated varieties by 23 and 69%, respectively. They were also the highest-yielding class in infertile, acid soils. The improved upland indica cultivars are about 110 cm tall under favorable upland conditions and maintain a harvest index of nearly 0.4, or about one-third higher than other cultivar types. The best upland-adapted rice varieties produced average yields on-farm of 3.3 and 4.1 t ha⁻¹ in southern Luzon and Yunnan, respectively, outyielding traditional checks by 30–50% with moderate N application. Screening under both high-fertility, non-stress conditions and moderate reproductive-stage stress appears to be needed to develop cultivars combining high-yield potential with drought tolerance. Upland-adapted indica cultivars offer a new approach to increasing productivity and reducing risk in Asian rainfed rice systems.     

Viscoelastic characterization of a new guar gum derivative containing anionic carboxymethyl and cationic 2-hydroxy-3-(trimethylammonio)propyl substituents

A new guar gum derivative (CMHTPG) containing anionic carboxymethyl and cationic 2-hydroxy-3-(trimethylammonio)propyl substituents was characterized with the help of a stress-controlled rheometer for its linear viscoelastic behavior in aqueous systems. The frequency-dependent elastic modulus (G′) and viscous modulus (G″) curves for 0.5, 1.0, 1.5 and 2.0 g/dl of aqueous CMHTPG solutions were found to cross at a given frequency. The crossover frequency value decreased with the increase of CMHTPG concentration. At 25 °C, the longest relaxation time was obtained to be 5.556 s for aqueous 2.0% CMHTPG solution while the shortest relaxation time to be 0.027 s for aqueous 0.5% CMHTPG solution, showing a strong concentration dependence on the viscoelastic properties. Moreover, the complex viscosity (η*) of aqueous CMHTPG solution was found to increase with the increase of CMHTPG concentration, and to decrease with the increase of frequency. By investigating the viscoelastic properties of aqueous CMHTPG salt solutions containing various concentrations of NaCl, it was observed that the addition of NaCl could lead to a slight increase in the G′, G″ or η* value. Temperature was confirmed to have an important influence on the viscoelastic properties of aqueous CMHTPG solution. For aqueous 1.0% CMHTPG solution, the activation energy reflecting the temperature sensitivity of the complex viscosity was determined at the frequency of 1.0 rad/s and found to be 16.94 kJ/mol.