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Maize Kernels (maize + kernel)
Selected AbstractsA simple DNA extraction method suitable for PCR detection of genetically modified maizeJOURNAL OF THE SCIENCE OF FOOD AND AGRICULTURE, Issue 14 2007Manuel Porcar Abstract BACKGROUND: The polymerase chain reaction (PCR) is a powerful tool that is being increasingly used for detection of transgenic DNA. PCR requires only a minute quantity of template, but sensitive and accurate testing requires DNA of sufficient purity and free from inhibitors such as plant polysaccharides. Several standard protocols are available for this purpose, but they usually involve several steps, imply destruction of the maize kernel, or are time-consuming. Our aim was to develop a fast and simple extraction method to isolate a raw DNA-containing solution from maize tissues suitable for use as a template in a PCR-based detection assay with specific oligonucleotides directed to the identification of event MON810. RESULTS: The NaOH-based DNA extraction method we report here is time-saving (5 min) and can be used to isolate DNA-containing solutions from a small maize leaf portion (down to 1 mg) or from a single overnight-germinated kernel. PCR performed with selected primers yielded reproducible detection of transgenic DNA. CONCLUSION: The main advantages of the procedure are the quick extraction step, the possibility of non-destructive testing of maize kernels, and the robustness of the PCR-based detection, a consequence of the selection of MON810-matching oligonucleotides yielding intense and highly specific amplicons. Copyright © 2007 Society of Chemical Industry [source] Occurrence of Toxic Hexadepsipeptides in Preharvest Maize Ear Rot Infected by Fusarium poae in PolandJOURNAL OF PHYTOPATHOLOGY, Issue 1 2007J. Che, kowski Abstract Twenty-seven preharvest maize ears affected by Fusarium poae rot (disease score 36,100%) were selected in 1998 and 1999 in Poland and examined for the occurrence of toxic hexadepsipeptides: beauvericin (BEA), enniatin A, enniatin B and enniatin B1. The identification of F. poae was confirmed by sequence analysis of variable internal transcribed spacer regions and compared with NCBI gene bank DNA sequences. Chemical analyses were performed by HPLC-MS. In 27 ears infected by F. poae were detected: BEA (trace to 46 ,g/g) in 18 samples, enniatin A (trace to 37 ,g/g) in nine samples, enniatin B (trace to 47 ,g/g) in 15 samples and enniatin B1 (trace to 25 ,g/g) in 12 samples. When 20 strains of F. poae isolated from these samples were cultured on rice, all produced BEA (1.9,75 ,g/g), three enniatin A (1.8,2 ,g/g), 12 enniatin B (1.1,5.1 ,g/g) and eight enniatin B1 (1.2,5.2 ,g/g). Occurrence and quantification of enniatin A, enniatin B and enniatin B1 and their co-occurrence with BEA in maize kernels is reported for the first time. [source] A simple DNA extraction method suitable for PCR detection of genetically modified maizeJOURNAL OF THE SCIENCE OF FOOD AND AGRICULTURE, Issue 14 2007Manuel Porcar Abstract BACKGROUND: The polymerase chain reaction (PCR) is a powerful tool that is being increasingly used for detection of transgenic DNA. PCR requires only a minute quantity of template, but sensitive and accurate testing requires DNA of sufficient purity and free from inhibitors such as plant polysaccharides. Several standard protocols are available for this purpose, but they usually involve several steps, imply destruction of the maize kernel, or are time-consuming. Our aim was to develop a fast and simple extraction method to isolate a raw DNA-containing solution from maize tissues suitable for use as a template in a PCR-based detection assay with specific oligonucleotides directed to the identification of event MON810. RESULTS: The NaOH-based DNA extraction method we report here is time-saving (5 min) and can be used to isolate DNA-containing solutions from a small maize leaf portion (down to 1 mg) or from a single overnight-germinated kernel. PCR performed with selected primers yielded reproducible detection of transgenic DNA. CONCLUSION: The main advantages of the procedure are the quick extraction step, the possibility of non-destructive testing of maize kernels, and the robustness of the PCR-based detection, a consequence of the selection of MON810-matching oligonucleotides yielding intense and highly specific amplicons. Copyright © 2007 Society of Chemical Industry [source] Synthesis of Novel Porous Magnetic Silica Microspheres as Adsorbents for Isolation of Genomic DNABIOTECHNOLOGY PROGRESS, Issue 2 2006Zhichao Zhang An improved procedure is described for preparation of novel mesoporous microspheres consisting of magnetic nanoparticles homogeneously dispersed in a silica matrix. The method is based on a three-step process, involving (i) formation of hematite/silica composite microspheres by urea-formaldehyde polymerization, (ii) calcination of the composite particles to remove the organic constituents, and (iii) in situ transformation of the iron oxide in the composites by hydrogen reductive reaction. The as-synthesized magnetite/silica composite microspheres were nearly monodisperse, mesoporous, and magnetizable, with as typical values an average diameter of 3.5 ,m, a surface area of 250 m2/g, a pore size of 6.03 nm, and a saturation magnetization of 9.82 emu/g. These magnetic particles were tested as adsorbents for isolation of genomic DNA from Saccharomyces cerevisiae cells and maize kernels. The results are quite encouraging as the magnetic particle based protocols lead to the extraction of genomic DNA with satisfactory integrity, yield, and purity. Being hydrophilic in nature, the porous magnetic silica microspheres are considered a good alternative to polystyrene-based magnetic particles for use in biomedical applications where nonspecific adsorption of biomolecules is to be minimized. [source] | ||||||||||