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991.
Chung HY Choi HR Park HJ Choi JS Choi WC 《Journal of agricultural and food chemistry》2001,49(8):3614-3621
Peroxynitrite (ONOO(-)), formed from the reaction of superoxide (O(2)*(-)) and nitric oxide (*NO), is a cytotoxic species that can oxidize several cellular components such as proteins, lipids, and DNA. It has been implicated in diseases such as Alzheimer's disease, rheumatoid arthritis, cancer, and atherosclerosis. Due to the lack of endogenous enzymes responsible for ONOO(-) inactivation, developing a specific ONOO(-) scavenger is of considerable importance. The aim of this study was to evaluate the ability of marine natural products to scavenge ONOO(-) and to protect cells against ONOO(-). Methanolic extracts of 17 marine alga were tested for their ONOO(-) scavenging activity. Among them, Symphyocladia latiuscula showed the potent scavenging activity. CH(2)CH(2) fraction was partitioned with CH(2)CH(2) following n-hexanal extraction from the methanol extract of S. latiuscula. It was highly effective for ONOO(-) scavenging activity. Further analysis of the active fractionated extract identified 2,3,6-tribromo-4,5-dihydroxybenzyl methyl ether (TDB) as a potent ONOO(-) scavenger. The data demonstrated that TDB led to decreased ONOO(-)-mediated nitration of tyrosine through electron donation. TDB showed significant inhibition on nitration of bovine serum albumin and low-density lipoprotein by ONOO(-) in a dose-dependent manner. It also provided cytoprotection from cell damage induced by ONOO(-). TDB can be developed as an effective peroxynitrite scavenger for the prevention of the involved diseases. 相似文献
992.
Recent evidence from nitrogen (N) saturation studies indicates that forest floors in moderately impacted forests are the primary sink for atmospheric N inputs. Some researchers have suggested that the sink capacity of organic horizons is dependent on the amount of available carbon (C), which can be used for microbial N assimilation. To test the hypothesis that C limitation in forest floors exposed to chronic N deposition leads to an enhanced N leaching, a field C input manipulation experiment is under way in a deciduous forest. Since September 1999 aboveground C input has been doubled (by doubling litter input or by amending glucose) or excluded in replicated plots. Here we report the short-term response of concentrations of dissolved inorganic N (DIN: NO3 ?-N and NH4 +-N) in forest floor percolate to the C input manipulation. In autumn following the C input manipulation, DIN concentrations in forest floor percolate decreased in all plots except the No Litter plots compared to the pre-treatment summer concentrations. In contrast, the concentrations of DIN in the No Litter plots remained high. A different seasonal pattern of DIN leaching among treatments, along with measurements of microbial biomass C and potential nitrification rates of forest floor samples, indicates that seasonal N dynamics in the forest floor are largely regulated by C availability changes assoicated with litterfall C input. 相似文献
993.
Films containing soy protein and wheat gluten were exposed to simulated farmland soil mix over a period of 30 days and monitored for degradation. The simulated farmland soil mix (topsoil/sand/Sunshine compost/vermiculite, 59:6:25:10, wt %) was mixed and stored at ambient humidity (48-55%) and temperature (20-24 degrees C); the soil mix was constantly maintained at 15% moisture by weight. Research focused on evaluating the effectiveness of gluten and cysteine additions on biodegradable behavior in the simulated farmland soil conditions. The four types of films, soy protein (S:G 1:0); soy protein with cysteine addition (S:G 1:0 + CYS); soy protein-wheat gluten (S:G 4:1); and soy protein-wheat gluten with cysteine addition (S:G 4:1 + CYS), were prepared at pH 7. 0 for degradation studies. Soy protein-gluten film rapidly degraded with 50% weight loss in about 10 days and with up to 95% weight loss in 30 days. Tensile strength and elongation of all soy protein-gluten films significantly decreased in 3 days. However, cysteine addition delayed the degradation rate of soy protein-gluten films. Soy protein-wheat gluten film disintegrated after 20 days in the simulated farmland soil environment. These results suggest that wheat gluten and cysteine addition to soy protein-based films could delay degradation rates due to their high disulfide contents. 相似文献
994.
The importance of ammonia (NH3) in the atmosphere andits role in acidification is increasingly recognized. Adetailed emission inventory of NH3 for South Korea iscarried out for different sources using emission factors.Results indicate that the emission of ammonia has increasedby 21% over the last 11 yr from 143 000 t yr-1 in1988 to 181 000 t yr-1 in 1998. The major contributorsto the NH3 emission in South Korea are livestock andfertilizer application that account for 70 and 26% oftotal NH3 emission, respectively. The 11 × 14 km (0.125° long. × 0.125° lat.) grid distribution of emission of ammonia shows an maximum in the Yochon area due to the largest fertilizer factory and relatively wide regions of high NH3 emission in thenorthwestern part of South Korea due to a great number of livestock. It is found that the nitrogen ratio of wet deposition of NH4 + to emission of NH3 in SouthKorea is averaged to be 0.45. 相似文献
995.
Dong Fu Liang Chen Guohui Yu Yi Liu Qiaojun Lou Hanwei Mei Liang Xiong Mingshou Li Xiaoyan Xu Lijun Luo 《Euphytica》2011,180(2):209-218
Sheath blight, caused by the pathogen Rhizoctonia solani Kühn, is one of the most serious diseases of rice and leads to severe yield loss worldwide. A recombinant inbred line (RIL)
population consisting of 121 lines was constructed from a cross between HH1B and RSB03, the latter of which is a deep-water
rice variety. Five traits were used to evaluate sheath blight resistance, namely disease rating (DR), lesion length (LL),
lesion height (LH), relative lesion length [RLL, the ratio of LL to plant height (PH)], and relative LH (RLH, the ratio of
LH to PH). Using the RIL population and 123 molecular markers, we identified 28 quantitative trait loci (QTLs) for the five
traits in two environments. These QTLs are located on nine chromosomes and most of them are environment specific. A major
QTL for DR (qSBR1) on chromosome 1 was identified with contributions of 12.7% at Shanghai and 42.6% at Hainan, and it collocated with a QTL
for PH. The allele at this locus from RSB03 enhances sheath blight resistance and increases PH. Another QTL for DR on chromosome 7
was adjacent to QTLs for heading date (HD) and four other disease traits. RSB03 also carries the resistant allele at this
locus and shortens HD. The susceptible parent, HH1B, provides the resistance allele at the locus qSBR8, where QTLs for four other disease traits were identified. QTL mapping results showed that most QTLs for LL, LH, RLL, and
RLH are collocated with QTLs for DR. Three QTLs for DR are independent from HD, PH, and four other disease traits, while four
QTLs are closely related to HD and PH. Four QTLs for LL, LH, RLL, and RLH are independent from DR, HD, and PH, while there
is only one region harboring QTLs for these four traits and HD. Correlation analysis and QTL mapping results indicated that
LL, LH, RLL, and RLH might be important indices, like DR, for evaluating the level of resistance to rice sheath blight. 相似文献
996.
András Cseri Mátyás Cserháti Maria von Korff Bettina Nagy Gábor V. Horváth András Palágyi János Pauk Dénes Dudits Ottó Törjék 《Euphytica》2011,181(3):341-356
In the present study, allele mining was conducted on a panel of drought related candidate genes in a set of 96 barley genotypes
using EcoTILLING, which is a variant of the targeting induced local lesions in genomes (TILLING) technology. Analyzing approximately
1.5 million basepairs in barley a total number of 94 verified unique haplotypes were identified in 18 amplicons designed for
9 genes. Overall, 185 single nucleotide polymorphisms (SNPs) and 46 insertions/deletions (INDELs) were detected with a mean
of 1SNP/92 bp and 1INDEL/372 bp genomic sequence. Based on overlapping haplotype sequences, markers were developed for four
candidate genes (HvARH1, HvSRG6, HvDRF1, HVA1), which allows distinguishing between the main haplotypes showing either differences in amino acid sequence or which have
larger INDELs in the promoter region. As “proof of concept”, the HvARH1 and HvSRG6 haplotypes were tested for the level of abscisic acid-induced gene expression in subsets of genotypes belonging to different
haplotype categories. An integrated database was developed to contain information about the genes, genotypes, and haplotypes
analyzed in this study. The database supplies profound information about the natural variation in the tested drought related
candidate genes providing a significant asset for further mapping studies dealing with this highly polygenic trait. 相似文献
997.
998.
Zhenfeng Jiang Binbin Zhang Weili Teng Yingpeng Han Xue Zhao Desheng Sun Zhongchen Zhang Wenbin Li 《Euphytica》2011,177(3):431-442
The oil accumulation in the developing soybean seed has been shown to be a dynamic process with different rates and activities
at different phases affected by both genotype and environment. The objective of the present study was to investigate additive,
epistatic and quantitative trait loci (QTL) × environment interaction (QE) effects of the QTL controlling oil filling rate
in soybean seed. A total of 143 recombinant inbred lines (RILs) derived from the cross of Charleston and Dongnong 594 were
used in this study to obtain 2 years of field data (2004 and 2005). A total of 26 QTL with significantly unconditional and
conditional additive (a) effect and/or additive × environment interaction (ae) effect at different filling stages were identified on 14 linkage groups. Among the QTL with significant a effects, 18 QTL showed positive effects and 6 QTL had negative effects on seed filling rate of oil content during seed development.
A total of 29 epistatic pairwise QTL underlying seed filling rate were identified at different filling stages. About 28 pairs
of the QTL showed additive × additive epistatic (aa) effects and 14 pairs of the QTL showed aa × environment interaction (aae) effects at different filling stages. QTL with aa and aae (additive × additive × environment) effects appeared to vary at different filling stages. Our results demonstrated that oil
filling rate in soybean seed were under genetic, developmental and environmental control. 相似文献
999.
Molecular genetics of race non-specific rust resistance in wheat 总被引:1,自引:0,他引:1
Evans S. Lagudah 《Euphytica》2011,179(1):81-91
Over 150 resistance genes that confer resistance to either leaf rust, stripe rust or stem rust have been catalogued in wheat
or introgressed into wheat from related species. A few of these genes from the ‘slow-rusting’ adult plant resistance (APR)
class confer partial resistance in a race non-specific manner to one or multiple rust diseases. The recent cloning of two
of these genes, Lr34/Yr18, a dual APR for leaf rust and stripe rust, and Yr36, a stripe rust APR gene, showed that they differ from other classes of plant resistance genes. Currently, seven Lr34/Yr18 haplotypes have been identified from sequencing the encoding ATP Binding Cassette transporter gene from diverse wheat germplasm
of which one haplotype is commonly associated with the resistance phenotype. The paucity of well characterised APR genes,
particularly for stem rust, calls for a focused effort in developing critical genetic stocks to delineate quantitative trait
loci, construct specific BAC libraries for targeted APR genes to facilitate robust marker development for breeding applications,
and the eventual cloning of the encoding genes. 相似文献
1000.
Haejeen Bang Dong Youn Cho Kil-Sun Yoo Moo-Kyoung Yoon Bhimanagouda S. Patil Sunggil Kim 《Euphytica》2011,179(3):439-449
In order to implement reliable marker-assisted selection systems for the restorer-of-fertility locus (Ms) in onions (Allium cepa L.), simple PCR-based codominant markers linked to the Ms locus were developed. Based on the EST probe sequences of previously reported RFLP markers, full-length genomic sequences
of the gene encoding putative oligopeptide transporter (OPT) was obtained by RACE. The first intron contained two 108 and
439-bp indel polymorphisms between the two Ms allele-linked OPT alleles. A simple PCR marker for OPT was developed by designing a primer pair on the flanking regions of
the 108-bp indel which is created by two tandem repeats. The second simple PCR marker was developed from the EST probe encoding
photosystem I subunit O (PsaO). Two 14 and 39-bp tandem repeats were identified from the 5′ upstream sequences of the PsaO-coding
gene, which were isolated by genome walking. Three different compositions of these tandem repeats were identified from diverse
onion germplasm. A primer set binding to the flanking sequence of these polymorphic repeats was used to amplify three different
marker haplotypes. The OPT marker was tightly linked to the Ms locus at a distance of 1.5 cM, but the analysis of the linkage relationship showed little linkage disequilibrium between
the marker and the Ms locus. Even so, these simple PCR markers are valuable tools for the marker-assisted selection of segregating individuals
in onion F1 hybrid breeding programs. 相似文献