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In this study, to fabricate stable floating photocatalytic spheres, facile alcohol solvothermal reduction was first employed to modify commercial TiO2 (P25) photocatalysts to harvest visible light and improve their performances for photodegrading phenol in seawater exciting by visible light. Floating photocatalytic spheres were then prepared by loading reduced P25 photocatalysts on inner and outer surfaces of acrylic hollow spheres. The structural characterizations showed that reduction of P25 introduced disorder-crystalline shell-core structures with present Ti3+ in reduced P25 photocatalysts. These features facilitated visible light response and phenol degradation in seawater under visible light irradiation. As reduction time or temperature of alcohol solvothermal process rose, more Ti3+ and shell-core structures were introduced into reduced P25, resulting in higher performances towards phenol degradation in seawater. However, extended periods of time and elevated temperatures decreased disordered layer of reduced P25, deteriorating the photocatalytic performances. Thanks to good light transmission of the hollow spheres and the high performance of the reduced P25, the photocatalytic performances of spheres loaded with reduced P25 could effectively degrade phenol in seawater even at low concentrations. The removal rate of phenol by floating spheres reached more than 95% after 8 h. In addition, the floating spheres displayed good stability and convenient reusability after six repeated photocatalytic degradation for phenol in seawater, promising features for future treatment of organic pollutants in oceans.

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Background Peanut (Arachis hypogaea L.) is an important economic and oilseed crop. Long-term rainless conditions and seasonal droughts can limit peanut yields and were conducive to preharvest aflatoxin contamination. To elucidate the molecular mechanisms by which peanut responds and adapts to water limited conditions, we isolated and characterized several drought-induced genes from peanut roots using a suppression subtractive hybridization (SSH) technique. Results RNA was extracted from peanut roots subjected to a water stress treatment (45% field capacity) and from control plants (75% field capacity), and used to generate an SSH cDNA library. A total of 111 non-redundant sequences were obtained, with 80 unique transcripts showing homology to known genes and 31 clones with no similarity to either hypothetical or known proteins. GO and KEGG analyses of these differentially expressed ESTs indicated that drought-related responses in peanut could mainly be attributed to genes involved in cellular structure and metabolism. In addition, we examined the expression patterns of seven differentially expressed candidate genes using real-time reverse transcription-PCR (qRT-PCR) and confirmed that all were up-regulated in roots in response to drought stress, but to differing extents. Conclusions We successfully constructed an SSH cDNA library in peanut roots and identified several drought-related genes. Our results serve as a foundation for future studies into the elucidation of the drought stress response mechanisms of peanut.

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BACKGROUND: The objective of this study was to investigate antioxidant and anti-inflammatory activity of cabbage phytochemicals. MATERIALS AND METHODS: Color coordinates were evaluated by colorimetry, and the antioxidant and anti-inflammatory activities were analyzed by spectrophotometer for some common cabbage varieties. RESULTS: Red heads had the highest total antioxidant contents followed by Savoy, Chinese and green heads. The Chinese variety had the highest ABTS (2,2-azino-di-(3-ethylbenzthiazoline-sulfonic acid) antioxidant activity, was 5.72 µmol TE/g fw (Trolox equivalent). The green variety had the highest DPPH (free radical scavenging activity) antioxidant activity, which was 91.2 µmol TE/g fw. The red variety had the highest FRAP (ferric reducing antioxidant power) antioxidant activity, which was 80.8 µmol TE/g fw. The total phenol amounts were 17.2-32.6 mM trolox equivalent antioxidant capacity (TEAC) and the total flavonoid amounts were 40.0-74.2 mg quercetin per gram. Methanolic extracts of different cabbage heads showed different anti-inflammatory activity values. Chinese, Savoy and green heads had the highest anti-inflammatory activity, while red heads had the lowest. CONCLUSIONS: The results suggest that these varieties of cabbage heads could contribute as sources of important antioxidant and anti-inflammatory related to the prevention of chronic diseases associated to oxidative stress, such as in cancer and coronary artery disease.

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Background: Based on the conserved sequences of a known NBS resistance gene, a pair of degenerate primers was designed to amplify the NBS-LRR resistance gene from peanut using PCR and RACE methods. Results: Analyzing the amino acid sequence by BLAST on NCBI, which was deduced from the 1088bp-long gene named PnAG1-2, showed that it had a certain homology with some resistance proteins, among which Arachis cardenasii resistance protein gene had the highest homology (66 percent). Relative quantification PCR analysis indicated that PnAG1-2 gene expresses more in J11 (an A. flavus-resistant variety) than in JH1012 (an A. flavus-susceptible variety) when the harvest time was coming. Conclusions: In this study, the NBS-LRR resistance sequence was successfully cloned from peanut and prokaryotic expression was done on the gene, which provided a foundation for cultivating anti-A. flavus peanut varieties.

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The preoxidation of polluted surface water with ferrate was conducted with respect to its impact on the following coagulation. It can be seen that UV254-absorbance, turbidity and TOC substantially decreased by 36.7%, 80.2%, 31.1%, respectively, after coagulation, without ferrate preoxidation, and by 63.3%, 89.6%, 37.0%, respectively, after coagulation, with ferrate preoxidation. It is noted that NH4+-N concentration is increased by 17% after coagulation with ferrate. This phenomenon can be explained by the fact that organics containing nitrogen in raw water were partly oxidized to inorganic nitrogen by ferrate preoxidation. After coagulation, AOC and AOC/TOC are increased from 998 microg x L(-1) to 1241 microg x L(-1), from 28.4% to 38.7%, respectively, by ferrate preoxidation. AOC-P17/AOC after coagulation is up to 83% with ferrate preoxidation. These suggest that preoxidation with ferrate promoted the biodegradation of organics with substantial increases of AOC, AOC/TOC. The results indicate that the concentration of organics with relative molecular mass (Mr) of 10000-100000 and less than 500 were substantially increased after the raw water was coagulated with ferrate preoxidation, which suggested that some high molecular weight organic substances were broken into smaller ones during ferrate preoxidation. After coagulation, organics of less than Mr = 500 in TOC are increased up to 65.0% with preoxidation from 38.9% without ferrate preoxidation. These oxidation products are biodegradable.

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This study found that the discolorization of malachite green solutions (0.01 mmol/L) was improved by Fe3+/H2O2 catalyzed with EDTA, at pH 7. Oxidation was carried out in presence of various hydrogen peroxide concentrations, in a wide range of temperature and EDTA concentration. It was found that oxidation with EDTA promoted the discolorization of MG from 43% to 98.3% as compared with the cases without EDTA. The discolorization of MG increased by 40% with the increase of EDTA concentration by 5 fold. The H2O2 concentration and temperature are higher, the discolorization of MG better, t-BuOH inhibited the improvement from EDTA. With the same total dosage of applied H2O2, the multiple steps addition did not show a much higher removal efficiency than that obtained by one step. OH free radical or an iron-oxo species may be the highly reactive oxidizing species, the latter may be the major oxidant. With the time, EDTA was a little oxidized.

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