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991.
992.
Di Paola-Naranjo RD Baroni MV Podio NS Rubinstein HR Fabani MP Badini RG Inga M Ostera HA Cagnoni M Gallegos E Gautier E Peral-Garcia P Hoogewerff J Wunderlin DA 《Journal of agricultural and food chemistry》2011,59(14):7854-7865
Our main goal was to investigate if robust chemical fingerprints could be developed for three Argentinean red wines based on organic, inorganic, and isotopic patterns, in relation to the regional soil composition. Soils and wines from three regions (Mendoza, San Juan, and Co?rdoba) and three varieties (Cabernet Sauvignon, Malbec, and Syrah) were collected. The phenolic profile was determined by HPLC-MS/MS and multielemental composition by ICP-MS; (87)Sr/(86)Sr and δ(13)C were determined by TIMS and IRMS, respectively. Chemometrics allowed robust differentiation between regions, wine varieties, and the same variety from different regions. Among phenolic compounds, resveratrol concentration was the most useful marker for wine differentiation, whereas Mg, K/Rb, Ca/Sr, and (87)Sr/(86)Sr were the main inorganic and isotopic parameters selected. Generalized Procrustes analysis (GPA) using two studied matrices (wine and soil) shows consensus between them and clear differences between studied areas. Finally, we applied a canonical correlation analysis, demonstrating significant correlation (r = 0.99; p < 0.001) between soil and wine composition. To our knowledge this is the first report combining independent variables, constructing a fingerprint including elemental composition, isotopic, and polyphenol patterns to differentiate wines, matching part of this fingerprint with the soil provenance. 相似文献
993.
Wszelaki N Paradowska K Jamróz MK Granica S Kiss AK 《Journal of agricultural and food chemistry》2011,59(17):9186-9193
Isolation and identification of the inhibitors of butyrylcholinesterase (BChE), obtained from the extracts of roots and fruits of Angelica archangelica L., are reported. Our results confirmed the weak inhibitory effect of Angelica roots on acetylcholinesterase activity. BChE inhibition was much more pronounced at a concentration of 100 μg/mL for hexane extracts and attained a higher rate than 50%. The TLC bioautography guided fractionation and spectroscopic analysis led to the isolation and identification of imperatorin from the fruit's hexane extract and of heraclenol-2'-O-angelate from the root's hexane extract. Both compounds showed significant BChE inhibition activity with IC(50) = 14.4 ± 3.2 μM and IC(50) = 7.5 ± 1.8 μM, respectively. Only C8-substituted and C5-unsubstituted furanocoumarins were active, which could supply information about the initial structures of specific BChE inhibitors. 相似文献
994.
Background
There is an increasing demand for renewable resources to replace fossil fuels. However, different applications such as the production of secondary biofuels or combustion for energy production require different wood properties. Therefore, high-throughput methods are needed for rapid screening of wood in large scale samples, e.g., to evaluate the outcome of tree breeding or genetic engineering. In this study, we investigated the intra-specific variability of lignin and energy contents in extractive-free wood of hybrid poplar progenies (Populus trichocarpa × deltoides) and tested if the range was sufficient for the development of quantitative prediction models based on Fourier transform infrared spectroscopy (FTIR). Since lignin is a major energy-bearing compound, we expected that the energy content of wood would be positively correlated with the lignin content. 相似文献995.
FlordeFátima Rosas-Cárdenas Noé Durán-Figueroa Jean-Philippe Vielle-Calzada Andrés Cruz-Hernández Nayelli Marsch-Martínez Stefan de Folter 《Plant methods》2011,7(1):4
Background
Small RNAs emerged over the last decade as key regulators in diverse biological processes in eukaryotic organisms. To identify and study small RNAs, good and efficient protocols are necessary to isolate them, which sometimes may be challenging due to the composition of specific tissues of certain plant species. Here we describe a simple and efficient method to isolate small RNAs from different plant species. 相似文献996.
Penultimate and last instar larvae of the common citrus swallowtail butterfly, Papilio demoleus L. (Papilionidae: Lepidoptera), were treated with different doses of a novel juvenoid, diofenolan. Several deformities were
observed as a result of topical administration of diofenolan which include delay in larval–larval and larval–pupal ecdysis,
ecdysial failure, mortality, severe reduction in pupation, deformed pupae and complete inhibition of adult emergence. The
juvenoid diofenolan severely hampers the normal growth, development and metamorphosis of P. demoleus and can be incorporated into integrated pest management programs for successful control of this important pest of citrus
all over the world. 相似文献
997.
Alate viviparous females of Wahlgreniella nervata (Gillette) were found on a Damask rose (Rosa damascena Mill.) plantation in Isparta Province, Turkey. The aphid is recorded for the first time from Turkey. Besides, Damask rose
is a new host for this species. Brief information about this aphid including a key to the alate females of aphid species known
to infest Damask rose in Turkey is provided. 相似文献
998.
Chao Zhou Yongqiang Liu Weili Yu Zhaorong Deng Ming Gao Feng Liu Wei Mu 《Phytoparasitica》2011,39(4):315-324
Spodoptera exigua (Hübner) collected from three regions (two scallion-producing regions and one ginger-producing region) in Shandong, China
and a laboratory colony of Wuhan (WHLC) were evaluated for their susceptibilities to ten insecticides (emamectin benzoate,
chlorfenapyr, indoxacarb, spinosyn, tebufenozide, methoxyfenozide, chlorfluazuron, beta-cypermethrin, chlorpyrifos and methomyl)
in 2008, 2009 and 2010 using a leaf-dip bioassay method. The results indicate that the resistance ratios of S. exigua to newer insecticides such as emamectin benzoate, chlorfenapyr and indoxacarb were all below 20-fold, with no obvious change
in all 3 years. S. exigua exhibits moderate resistance to spinosyn, and its resistance ratios increased from 1.98–5.31-fold in 2008 to 14.31–64.20-fold
in 2010 from three regions as compared with WHLC. S. exigua showed moderate to high resistance to insect growth regulators such as tebufenozide, methoxyfenozide, chlorfluazuron in 2008,
2009 and 2010, in which resistance to chlorfluazuron was rapidly increased from 31.49–88.19-fold in 2008 to 1184.39–2789.67-fold
in 2010. Resistance of S. exigua to beta-cypermethrin and chlorpyrifos varied greatly among the three regions, ranging from 95.31–437.97-fold and 25.05–40.64-fold
in 2008, 951.81–1304.40-fold and 44.91–186.33-fold in 2009, to 27.27–1095.31-fold and 19.12–267.98-fold in 2010. In contrast,
S. exigua showed low resistance to methomyl, and the resistance ratio was below 5-fold in 3 years. There are several reasons accounting
for varying degrees of resistance, including selection pressure, cropping structure and migration, in which the migration
of S. exigua may play an important role. 相似文献
999.
1000.