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141.
Hedrick P 《Science (New York, N.Y.)》2010,330(6012):1744; author reply 1744
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Floudas D Binder M Riley R Barry K Blanchette RA Henrissat B Martínez AT Otillar R Spatafora JW Yadav JS Aerts A Benoit I Boyd A Carlson A Copeland A Coutinho PM de Vries RP Ferreira P Findley K Foster B Gaskell J Glotzer D Górecki P Heitman J Hesse C Hori C Igarashi K Jurgens JA Kallen N Kersten P Kohler A Kües U Kumar TK Kuo A LaButti K Larrondo LF Lindquist E Ling A Lombard V Lucas S Lundell T Martin R McLaughlin DJ Morgenstern I Morin E Murat C Nagy LG Nolan M Ohm RA Patyshakuliyeva A 《Science (New York, N.Y.)》2012,336(6089):1715-1719
Wood is a major pool of organic carbon that is highly resistant to decay, owing largely to the presence of lignin. The only organisms capable of substantial lignin decay are white rot fungi in the Agaricomycetes, which also contains non-lignin-degrading brown rot and ectomycorrhizal species. Comparative analyses of 31 fungal genomes (12 generated for this study) suggest that lignin-degrading peroxidases expanded in the lineage leading to the ancestor of the Agaricomycetes, which is reconstructed as a white rot species, and then contracted in parallel lineages leading to brown rot and mycorrhizal species. Molecular clock analyses suggest that the origin of lignin degradation might have coincided with the sharp decrease in the rate of organic carbon burial around the end of the Carboniferous period. 相似文献
143.
A method for estimating the total limonoid aglycone and glucoside concentrations in Citrus samples in terms of limonin and limonin glucoside equivalents is presented. The method consists of extraction followed by colorimetric quantification. The colorimetric quantification was based on the formation of red to orange colored derivatives resulting from the treatment of limonin, limonin glucoside, or a fruit extract with 4-(dimethylamino)benzaldehyde (DMAB) in the presence of perchloric and acetic acids. Absorbance maxima for the limonin and limonin glucoside derivatives were found to be 470 and 503 nm, respectively. The influence of DMAB concentration, reaction time, and solvent composition on color development and sensitivity were investigated and optimal assay conditions established. With a microplate format under these conditions, the limits of detection and quantification were determined to be 0.25 and 0.50 microg/mL for limonin and 0.50 and 1.0 microg/mL for limonin glucoside. 相似文献
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Toole GA Le Gall G Colquhoun IJ Johnson P Bedo Z Saulnier L Shewry PR Mills EN 《Journal of agricultural and food chemistry》2011,59(13):7075-7082
Fifty bread wheat (Triticum aestivum L.) cultivars were selected from the HEALTHGRAIN germplasm collection based on variation in their contents of total and water-extractable arabinoxylan. FT-IR spectroscopic mapping of thin transverse sections of grain showed variation in cell wall arabinoxylan composition between the cultivars, from consisting almost entirely of low-substituted arabinoxylan (e.g., T.aestivum 'Claire') to almost entirely of highly substituted arabinoxylan (e.g., T.aestivum 'Manital') and a mixture of the two forms (e.g., T.aestivum 'Hereward'). Complementary data were obtained using endoxylanase digestion of flour followed by HP-AEC analysis of the arabinoxylan oligosaccharides. This allowed the selection of six cultivars for more detailed analysis using FT-IR and (1)H NMR spectroscopy to determine the proportions of mono-, di-, and unsubstituted xylose residues. The results of the two analyses were consistent, showing that variation in the composition and structure of the endosperm cell wall arabinoxylan is present between bread wheat cultivars. The heterogeneity and spatial distribution of the arabinoxylan in endosperm cell walls may be exploited in wheat processing as it may allow the production of mill streams enriched in various arabinoxylan fractions which have beneficial effects on health. 相似文献
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Julie Beckstead Laura E. Street Susan E. Meyer Phil S. Allen 《Strength and Conditioning Journal》2011,64(2):148-157
The generalist fungal pathogen Pyrenophora semeniperda occurs primarily in cheatgrass (Bromus tectorum) seed banks, where it causes high mortality. We investigated the relationship between this pathogen and its cheatgrass host in the context of fire, asking whether burning would facilitate host escape from the pathogen or increase host vulnerability. We used a series of laboratory and field experiments to address the ability of host seeds and pathogen life stages to survive fire. First, we determined the thermal death point (TDP50; temperature causing 50% mortality) of seeds and pathogen propagules at two time intervals using a muffle furnace. We then measured peak fire temperatures in prescribed burns at sites in Utah and Washington and quantified seed and fungal propagule survival using pre- and postburn seed bank sampling and inoculum bioassays. Finally, we investigated the survival of both seeds and pathogen after wildfires. We found that radiant heat generated by both prescribed and wild cheatgrass monoculture fires was generally not sufficient to kill either host seeds or pathogen propagules; most mortality was apparently due to direct consumption by flames. The 5-min mean TDP50 was 164°C for pathogen propagules and 148°C for host seeds, indicating that the pathogen is more likely to survive fire than the seeds. Peak fire temperature at the surface in the prescribed burns averaged 130°C. Fire directly consumed 85–98% of the viable seed bank, but prescribed burns and wildfires generally did not lead to dramatic reductions in pathogen inoculum loads. We conclude that the net effect of fire on this pathosystem is not large. Rapid postburn recovery of both host and associated pathogen populations is the predicted outcome. Postfire management of residual cheatgrass seed banks should be facilitated by the persistent presence of this seed bank pathogen. 相似文献
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Huan Wang Kun Phil Kim In Ho Kim 《Journal of animal physiology and animal nutrition》2019,103(6):1919-1925
The present study investigated the influence of Bacillus subtilis GCB‐13‐001 on growth performance, nutrient digestibility, blood characteristics, faecal microbiota and faecal score in weanling pigs. A total of 120 weaning pigs [(Landrace × Yorkshire) × Duroc; 7.73 ± 0.75 kg (28 days of age)] were randomly allotted into three treatments according to their initial body weight (BW) and gender in a 6‐week experiment. There were 8 replication pens in each treatment, with five pigs/pen. Dietary treatment groups were as follows: (a) basal diet (CON), (b) CON + 0.1% Bacillus subtilis GCB‐13‐001 1 × 108 CFU/kg (T1) and (c) CON + 0.1% Bacillus subtilis GCB‐13‐001 1 × 109 CFU/kg (T2). Days 1 to 7, the BW and ADG with T2 treatment were higher (p < .05) than CON treatment, as well as F:G showed trends in linear reduction (p < .1). Days 8 to 21, the BW and ADG were improved (p < .05) in pigs offered T1 and T2 diets compared with CON diet. Days 22 to 42, BW and ADG were higher (p < .05) in pigs fed T2 diet than CON and T1 diets, and the pigs fed T1 diet had higher BW than CON treatment. Overall, the ADG with the T2 treatment was higher (p < .05) than that with the T1 and CON treatments, and pigs offered T1 treatment had higher (p < .05) ADG than CON treatment. Moreover, F:G ratio were significantly decreased (p < .05) by T2 treatment compared with CON treatment. The faecal Lactobacillus counts were improved, and E. coli counts were reduced (p < .05) in pigs fed T2 diet compared with CON at the end of the experiment. In conclusion, supplementation of 0.1% Bacillus subtilis GCB‐13‐001 1 × 109 CFU/kg has shown a beneficial effect in improving BW, increase ADG, decrease F:G ratio. 相似文献