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Maize Grain (maize + grain)
Selected AbstractsHPLC-PAD-APCI/MS assay of phenylpropanoids in cerealsPHYTOCHEMICAL ANALYSIS, Issue 1 2004Antoine C. Bily Abstract A new, rapid HPLC-PAD-APCI/MS assay has been developed in order to measure accurately the amount of p -coumaric, E - and Z -ferulic acid and the dehydrodimers of ferulic acid in cereal grain. In the positive ionisation mode, MS patterns gave additional information for the identi,cation of the dimers. The time required and the quantities of solvents employed in the developed analytical method are much lower than those involved in previously available assays of these compounds, thus making the method suitable for the screening of cereal genotypes. Application of the method to accessions of maize, wheat and sorghum showed that E -ferulic was the most abundant phenylpropanoid, whilst the major dimer was 8- O -4, dehydrodimer of ferulic acid followed by the 5,5, and then the 8,5, forms. Maize grains, especially of the Mexican landraces, contained the highest levels of these dimers. Copyright © 2004 John Wiley & Sons, Ltd. [source] Soil greenhouse gas fluxes and global warming potential in four high-yielding maize systemsGLOBAL CHANGE BIOLOGY, Issue 9 2007M. A. A. ADVIENTO-BORBE Abstract Crop intensification is often thought to increase greenhouse gas (GHG) emissions, but studies in which crop management is optimized to exploit crop yield potential are rare. We conducted a field study in eastern Nebraska, USA to quantify GHG emissions, changes in soil organic carbon (SOC) and the net global warming potential (GWP) in four irrigated systems: continuous maize with recommended best management practices (CC-rec) or intensive management (CC-int) and maize,soybean rotation with recommended (CS-rec) or intensive management (CS-int). Grain yields of maize and soybean were generally within 80,100% of the estimated site yield potential. Large soil surface carbon dioxide (CO2) fluxes were mostly associated with rapid crop growth, high temperature and high soil water content. Within each crop rotation, soil CO2 efflux under intensive management was not consistently higher than with recommended management. Owing to differences in residue inputs, SOC increased in the two continuous maize systems, but decreased in CS-rec or remained unchanged in CS-int. N2O emission peaks were mainly associated with high temperature and high soil water content resulting from rainfall or irrigation events, but less clearly related to soil NO3 -N levels. N2O fluxes in intensively managed systems were only occasionally greater than those measured in the CC-rec and CS-rec systems. Fertilizer-induced N2O emissions ranged from 1.9% to 3.5% in 2003, from 0.8% to 1.5% in 2004 and from 0.4% to 0.5% in 2005, with no consistent differences among the four systems. All four cropping systems where net sources of GHG. However, due to increased soil C sequestration continuous maize systems had lower GWP than maize,soybean systems and intensive management did not cause a significant increase in GWP. Converting maize grain to ethanol in the two continuous maize systems resulted in a net reduction in life cycle GHG emissions of maize ethanol relative to petrol-based gasoline by 33,38%. Our study provided evidence that net GHG emissions from agricultural systems can be kept low when management is optimized toward better exploitation of the yield potential. Major components for this included (i) choosing the right combination of adopted varieties, planting date and plant population to maximize crop biomass productivity, (ii) tactical water and nitrogen (N) management decisions that contributed to high N use efficiency and avoided extreme N2O emissions, and (iii) a deep tillage and residue management approach that favored the build-up of soil organic matter from large amounts of crop residues returned. [source] Impact of environment and interactions of Fusarium verticillioides and Fusarium proliferatum with Aspergillus parasiticus on fumonisin B1 and aflatoxins on maize grainJOURNAL OF THE SCIENCE OF FOOD AND AGRICULTURE, Issue 11 2001Sonia Marín Abstract Fusarium verticillioides and F proliferatum isolates were inoculated in mixed cultures with Aspergillus parasiticus on irradiated maize grain at two different inoculum concentrations (2,×,105 and 2,×,102 conidia g,1 dry maize). The treatments were 0.93,0.98 water activity (aw) and 15 and 25,°C for 28 days. A complex relationship was found between aw, temperature, inoculum concentration and the interactions which took place between fumonisin and aflatoxin producers. In general, A parasiticus reduced F verticillioides and F proliferatum populations (by 6,36%) but did not affect fumonisin B1 production by these species. In contrast, while the Fusarium species were not able to decrease A parasiticus populations, they significantly reduced aflatoxin B1 accumulation (by 30,93%). © 2001 Society of Chemical Industry [source] Chapter 6: Maize with Increased Lysine (Lysine Maize,LY038)COMPREHENSIVE REVIEWS IN FOOD SCIENCE AND FOOD SAFETY, Issue 1 2008Article first published online: 30 JAN 200 ABSTRACT:, Data and information provided in this case study relate to a crop derived by modern biotechnology, in which a specific nutrient (lysine) has been increased in maize grain.Lysine maize is a feed ingredient with enhanced nutritional characteristics for poultry and swine and provides an alternative to adding supplemental lysine to diets for these animals. Lysine maize is in an advanced state of development; therefore, extensive unpublished data and information are presented to demonstrate that (1) Lysine maize,and the feeds and foods derived from it,are as safe as those derived from conventional maize,and (2) the increased lysine in Lysine maize grain produces the intended nutritional benefit for broiler chickens when compared to a diet containing conventional maize grain and a crystalline lysine supplement. These conclusions are based on a detailed molecular characterization of Lysine maize,a safety assessment of the introduced protein,a safety and nutritional assessment of the LY038 crop,and a comparison of the agronomic and phenotypic properties of maize hybrids with and without the Lysine maize trait. Although Lysine maize is a specialty crop for use in animal feed,its safety for both animals and humans must be demonstrated. Free lysine is significantly increased in Lysine maize by the introduction of the dapA gene (cordapA) from Corynebacterium glutamicum that encodes a form of dihydrodipicolinate synthase (cDHDPS) that is insensitive to lysine feedback inhibition.Analysis of lysine anabolic and catabolic pathways in maize identified 6 metabolites that might change as a consequence of the introduction of cDHDPS insensitive to lysine-feedback inhibition. The results of compositional analysis demonstrated that Lysine maize grain is comparable to conventional maize, with the exception of the intended increase in lysine and a corresponding increase in 2 products of lysine catabolism,saccha-ropine and -aminoadipic acid. Therefore, the safety and/or nutritional implication of these 3 compounds under the conditions of use were the focus of additional assessments and found to not present either a safety or nutritional problem. [source] | ||||||||||