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The antioxidative properties of a hot water extract of the leaves of Mallotus japonicus were evaluated. The extract had a high phenolic content and strong antioxidative activity, compared with green tea, rooibos tea, and red wine. Six phenolic compounds were isolated as antioxidative components by HPLC. They were identified as mallotinic acid, mallotusinic acid, corilagin, geraniin, rutin, and ellagic acid. These antioxidative compounds were subjected to DPPH radical-scavenging, superoxide radical-scavenging, and hydroxyl radical-scavenging assays, and compared with other antioxidative compounds. Four of the compounds, mallotinic acid, mallotusinic acid, corilagin and geraniin, exhibited much stronger antioxidative activity than gallic acid, rutin, ellagic acid, quercetin, and chlorogenic acid, and were as active as epigallocatechin gallate (EGCG), a strong antioxidant in green tea. Mallotus japonicus leaves are an excellent source of strong natural antioxidative materials.  相似文献   
83.
A variety of factors, including concentration of oil, antibiotics, dyes, and inoculum washes, were examined to determine their effect on the total counts of microorganisms on oil-containing media. The media found to be best for enumerating petroleum-degrading microorganisms contained 0.5% (vol/vol) oil and 0.003% phenol red, with Fungizone added for isolating bacteria and streptomycin and tetracycline added for isolating yeasts and fungi. Washing the inoculum did not improve recovery of petroleum degraders. Specifically, silica gel-oil medium and a yeast medium are recommended for enumeration of petroleum-degrading bacteria and yeasts and fungi, respectively. It is suggested that counts of petroleum degraders be expressed as percentage of the total population rather than total numbers of petroleum degraders per se. Incubation temperature and presence of oil was found to influence the numbers of petroleum-degrading microorganisms at a given sampling site.  相似文献   
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During the accident that occurred at the Fukushima Daiichi nuclear power plant, a large volume of seawater was introduced as coolant into the storage pools for spent nuclear fuel. If this fuel is reprocessed, some components of seawater will be mixed with the nitric acid solution containing metal ions in the reprocessing process where stainless steels are used as structural material. In this study, we investigated the effect of seawater components in high active liquid waste (HAW) containing nitric acid and metal ions as fission products on the corrosion behavior of SUS316L stainless steel.

Corrosion tests were conducted in surrogate HAW containing artificial seawater (ASW). Intergranular corrosion was observed in the HAW with ASW, where Ru increased the corrosion potential to the transpassive region. An increase in the amount of ASW led to a decrease in the corrosion rate and suppression of intergranular corrosion. Interactions between Ru ions and seawater components, such as chloride ions, were indicated by the results of extended X-ray absorption fine structure spectroscopy and cyclic voltammetry analyses of the solution containing ASW and HAW.  相似文献   

86.
Cholesterol has been detected as one of the major sterols in the surface lipids of higher plant leaves. It was widely distributed among the plant leaves of various species as a common main sterol component with a few exceptions. The content of cholesterol amounted to 71.5% of the total sterols in the surface lipids of rape leaves. However, the proportion of cholesterol in the intracellular lipids of rape leaves was lower than that in the surface lipids, and the seed lipids contained only a trace amount of cholesterol, as reported in the literature. In the leaf surface lipids examined, a minor amount of cholestanol associated with cholesterol often was detected by capillary gas chromatography and gas chromatography-mass spectrometry. The related analysis for the surface lipids of fruits showed that cholesterol was one of the major component sterols also in those lipids of several species.  相似文献   
87.
Sorption-desorption column tests using acrylic columns (? 5 cm × h 10 cm) were employed to evaluate the sorption performance of an attenuation layer against geogenic contamination. The attenuation layer material was silica sand amended with 1, 5, or 10% of a stabilising agent. The main component of the agent was magnesium oxide. The sorption behaviour of the materials was determined by a fluoride solution (C0 = 80 mg/L F-), while the desorption behaviour was determined by distilled water. Breakthroughs (C/C0 > 0.05) occurred after approximately 1, 20, and 50 PVF for stabilising agent contents of 1, 5, and 10%, respectively. The one-dimensional advection-dispersion equation modelled the breakthrough curves obtained from the tests. The predictions gave unrealistic estimates, especially for the breakthrough point where C/C0 = 0.05. For the 1% agent content, approximately 20% of the sorbed mass, Ss, was desorbed, but the percentage of desorbed mass, Sd, was much smaller for the higher agent contents. The difference between the sorbed and desorbed masses was defined as the immobilised fraction, Ss - Sd. For the 5% agent content, Ss - Sd = 4.0 mg/g. The results suggest that when silica sand is amended with magnesium oxide as an agent, the mixture can immobilise the fluoride in the attenuation layer.  相似文献   
88.
Scope: To determine the effect of consumption of a quercetin‐rich diet on obesity and dysregulated hepatic gene expression. Methods and results: C56BL/6J mice were fed for 20 wk on AIN93G (control) or a Western diet high in fat, cholesterol and sucrose, both with or without 0.05% quercetin. Triglyceride levels in plasma, thiobarbituric acid‐reactive substances (oxidative stress marker) and glutathione levels and peroxisome proliferator‐activated receptor α expression in livers of mice fed with the Western diet were all improved after 8 wk feeding with quercetin. After 20 wk, further reductions of visceral and liver fat accumulation and improved hyperglycemia, hyperinsulinemia, dyslipidemia and plasma adiponectin and TNFα levels in these mice fed with quercetin were observed. The expression of hepatic genes related to steatosis, such as peroxisome proliferator‐activated receptor γ and sterol regulatory element‐binding protein‐1c was also normalized by quercetin. In mice fed with the control diet, quercetin did not affect body weight but reduces the plasma TNFα and hepatic thiobarbituric acid‐reactive substance levels. Conclusion: In mice fed with a Western diet, chronic dietary intake of quercetin reduces liver fat accumulation and improves systemic parameters related to metabolic syndrome, probably mainly through decreasing oxidative stress and reducing PPARα expression, and the subsequent reduced expression in the liver of genes related to steatosis.  相似文献   
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