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991.
Perfluorooctanesulfonate and related fluorochemicals in human blood samples from China 总被引:3,自引:0,他引:3
Yeung LW So MK Jiang G Taniyasu S Yamashita N Song M Wu Y Li J Giesy JP Guruge KS Lam PK 《Environmental science & technology》2006,40(3):715-720
Perfluorooctanesulfonylfluoride (POSF)-based compounds have been manufactured and used in a variety of industrial applications. These compounds degrade to perfluorooctanesulfonate (PFOS) which is regarded as a persistent end-stage metabolite and is found to accumulate in tissues of humans and wildlife. PFOS, perfluorohexanesulfonate (PFHxS), perfluorooctanoate (PFOA), and perfluorooctanesulfonamide (PFOSA) have been found in human sera from the United States. In this study, concentrations of PFHxS, perfluorobutanesulfonate (PFBS), PFOS, perfluorohexanoic acid (PFHxA), PFOA, perfluorononanoic acid (PFNA), perfluorodecanoic acid (PFDA), perfluoroundecanoic acid (PFUnDA), perfluorododecanoic acid (PFDoDA), and PFOSA were measured in 85 samples of whole human blood collected from nine cities (eight provinces) in China, including Shenyang (Liaoning), Beijing (Hebei), Zhengzhou (Henan), Jintan (Jiangsu), Wuhan (Hubei), Zhoushan (Zhejiang), Guiyang (Guizhou), Xiamen (Fujian), and Fuzhou (Fujian). Among the 10 perfluorinated compounds (PFCs) measured, PFOS was the predominant compound. The mean concentration of PFOS was greatest in samples collected from Shenyang (79.2 ng/mL) and least in samples from Jintan (3.72 ng/mL). PFHxS was the next most abundant perfluorochemical in the samples. No age-related differences in the concentrations of PFOA, PFOS, PFOSA, and PFHxS were observed. Gender-related differences were found,with males higher for PFOS and PFHxS, and females higher in PFUnDA. Concentrations of PFHxS were positively correlated with those of PFOS, while concentrations of PFNA, PFDA, and PFUnDA were positively correlated with those of PFOA. There were differences in the concentration profiles (percentage composition) of various PFCs in the samples among the nine cities. 相似文献
992.
Paul M Cinciripini Jason D Robinson Brian L Carter Cho Lam XiFeng Wu Carl A de Moor Walter F Baile David W Wetter 《Nicotine & tobacco research》2006,8(3):379-392
Although converging lines of evidence suggest that nicotine and mood are related at a fundamental biological level, this link has not been reliably demonstrated in laboratory studies. In this study, startle probe methodology was used to examine the effects of nicotine administration and deprivation on emotional processes associated with motivation. Smokers (N = 115) completed four laboratory sessions crossing deprivation (12-hr deprived vs. nondeprived) with nicotine spray (active vs. placebo). Participants viewed affective pictures (positive, negative, neutral) and pictures involving cigarette cues, while startle probes were administered. Deprivation decreased startle responding to cigarette cues, suggesting an activation of appetitive processes. Nicotine administration suppressed overall startle responding during deprivation. In addition, during deprivation, random exposure to negative stimuli over two blocks of trials resulted in decreased adaptation of the startle response, suggesting that some sensitization to negative emotional cues may take place during nicotine withdrawal. These effects are consistent with formulations of addiction, stressing that withdrawal may both increase the reinforcement salience of smoking stimuli and decrease habituation to negative emotional stimuli. 相似文献
993.
Cadmium pollution from the manufacture and disposal of NiCd batteries remains an important problem in developing countries. Among the available remedial technologies, adsorption is popular because of its low cost and simplicity. The mesoporous NH2-MCM-41 displays good adsorption capacities for cadmium and nickel ions. This work demonstrated for the first time the use of the competition between complexant and sorbentto create high adsorption selectivity. The selectivity was manipulated by the judicious use of a chelating agent, thus achieving on-demand 100% selectivity for either Cd2+ or Ni2+ adsorption. Single and binary components adsorption studies, carried out with different metals and EDTA concentrations, solution compositions and pH, showed that NH2-MCM-41 adsorbs only cadmium with a capacity of 0.56 mmol g(-1) from binary mixtures at [EDTA]/[M2+] = 0.5 and pH 5. The NH2-MCM-41 displays 100% selectivityfor nickel adsorption at [EDTA]/[M2+] = 0.5 and pH 2 with a measured adsorption capacity of 0.50 mmol g(-1). Pure Cd2+ and Ni2+ solutions were recovered by a simple acid wash, and the regenerated adsorbent could be reused without lost of performance (i.e., adsorption capacity and selectivity). 相似文献
994.
Bacillus cereus is a foodborne spore-forming bacterial pathogen that is ubiquitous in the natural environment. Infections with this pathogen manifest as diarrheal or emetic types of food poisoning. In this study, 140 samples of dried red pepper purchased in Korea were assayed for the presence of B. cereus according to the U.S. Food and Drug Administration standard culture method. A multiplex PCR assay was developed for the rapid confirmation of B. cereus as an alternative to conventional biochemical confirmation tests. The genetic diversity of B. cereus isolates was investigated using a random amplified polymorphic DNA (RAPD) assay. B. cereus was found in 84.3% of the dried red pepper samples, with an average concentration of 1.9 x 10(4) CFU/g. B. cereus could be detected and distinguished from B. thuringiensis in the multiplex PCR assay by using the BCFW1 plus BCrevnew and the K3 plus K5 primer sets designed to detect the gyrB gene of B. cereus and B. thuringiensis and the cry gene of B. thuringiensis. A RAPD assay using the OPG 16 and MUP 3 primers was used to successfully distinguish among isolates, thus elucidating the genetic diversity of B. cereus isolates. The discriminating ability of the OPG 16 primer (142 types) was about threefold higher than that of MUP 3 (52 types) in the RAPD assay. 相似文献
995.
Unraveling the structural components of soil humin by use of solution-state nuclear magnetic resonance spectroscopy 总被引:1,自引:0,他引:1
Simpson AJ Song G Smith E Lam B Novotny EH Hayes MH 《Environmental science & technology》2007,41(3):876-883
Humin is the most recalcitrant and least understood fraction of soil organic matter. By definition, humin is that fraction not extracted by traditional aqueous alkaline soil extractants. Here we show that > or = 70% of the traditional humin fraction is solubilized when 0.1 M NaOH + 6 M urea and dimethyl sulfoxide (DMSO) + 6% H2SO4 are used in series after conventional extraction. Multidimensional solution-state NMR is applied in this study to gain an understanding of the major constituents present in these "solubilized humin fractions". The spectra indicated strong contributions from five main categories of components, namely, peptides, aliphatic species, carbohydrates, peptidoglycan, and lignin. Diffusion edited spectroscopy indicated that all species are present as macromolecules (or stable aggregate species). Although the distribution of the components is generally similar, peptidoglycan is present at significant levels supporting a higher microbial contribution to humin than to humic and fulvic fractions. The abundance of plant- and microbial-derived materials found does not exclude "humic" materials (e.g., oxidized lignin) or the presence of novel compounds at lower concentrations but suggests that a large proportion of humin is formed from classes of known compounds and parent biopolymers. 相似文献
996.
Effects of gamma‐irradiated soybean pod extract on oxidative stress,cancer cell viability,and tyrosinase inhibition 下载免费PDF全文
Ji Hae Lee Koan Sik Woo Jae‐Kyung Kim Mijung Kim Byong Won Lee Eunyeong Sim Yong‐Hee Jeon Choon‐Ki Lee Hyun‐Joo Kim 《Journal of Food Biochemistry》2018,42(1)
Soybean pods contain abundant dietary fiber and phytochemicals, including phenolic compounds. However, few bioactivity studies have been conducted using soybean pods, while soybean leaves, and seeds have been well characterized. In this study, the effect of gamma irradiation on the physiological properties of soybean pod extract (SPE) was investigated. SPE was irradiated at 0, 5, 10, and 20 kGy, and the phenolic compound concentration and antioxidant activity were investigated. The total phenolic compounds were increased and total flavonoids were decreased as the irradiation dose increased. Antioxidant activity, which was measured using the 2,2‐diphenyl‐1‐picrylhydrazyl, 2,2′‐azino‐bis‐3‐ethylbenzothiazoline‐6‐sulphonic acid, and 2‐thiobarbituric acid reactive substances assays, improved as the irradiation dose increased. In addition, cancer cell viability, and tyrosinase activity were reduced by gamma irradiation. These results show that soybean pods can be utilized as functional food materials after gamma irradiation.
Practical applications
Gamma irradiation modified the chemical composition of soybean pod extract (SPE). Such irradiation improved the antioxidant, anti‐pigmentation, and anti‐carcinogenesis effects compared to those of control SPE. Therefore, this material, previously considered a byproduct of soybean processing, can be used as a functional food to prevent such disorders as oxidative damage, cancer, and hyperpigmentation. 相似文献997.
Srinivasaraonaik B Lok Pratap Singh Inderjeet Tyagi Anujay Rawat Shishir Sinha 《国际能源研究杂志》2020,44(5):3854-3864
In the present work, microencapsulated phase change material (M-PCM) has been synthesized with eutectic mixture (75% SA + 25% CA) as core and melamine formaldehyde (MF) as shell using in situ polymerization. Advanced instrumental techniques like field emission scanning electron microscopy (FE-SEM), Fourier-transform infrared spectroscopy (FT-IR), particle size analyzer (PSA), thermogravimetric/differential thermal analysis (TG/DTA), differential scanning calorimetry (DSC), and thermal conductivity analyzer (TCi) were used to characterize the synthesized M-PCM, and impact of effective parameters like pH and agitator speed on the encapsulation process was also elucidated. Results obtained reveal that at the optimized pH (3.2) and agitator speed (1500 rpm) M-PCM possess smooth surface morphology, spherical in shape with particle size of 10.41 μm. Based on FT-IR analysis, it was observed that the synthesized M-PCM was uniformly encapsulated by MF resin with eutectic mixture in the core. The encapsulation process results in the improvement of the thermal stability of eutectic mixture, it increases from 202.5 to 212.3°C, and the encapsulation efficiency of the M-PCM is found to be 85.3%. The melting point and latent heat of fusion of M-PCM were found to be 34.5°C and 103.9 kJ/kg, respectively. 相似文献
998.
Hyun Young Kim Sang Hoon Lee In Guk Hwang Koan Sik Woo Kee Jong Kim Mi Ja Lee Dae Joong Kim Tae Jip Kim Junsoo Lee Heon Sang Jeong 《Food science and biotechnology》2013,22(1):181-186
This study investigated the changes in antioxidant and antiproliferation activities of germinated winter cereal crops, including oats, barley, rye, and wheat, to develop functional materials. The highest total polyphenol content was found post-germination at 3.97 mg gallic acid equiv./g, which was 1.61-fold higher than the 2.46 mg gallic acid equiv./g in pre-germination barley. The flavonoid content was highly increased in wheat, which was 2.25-fold higher than 0.28 mg catechin equiv./g sample in pre-germination. The DPPH free radical scavenging activity (IC50) was the greatest in the post-germination barley at 1.67 mg/mL. The highest ascorbic acid equivalent antioxidant capacity (7.43 mg AA eq/g sample) was obtained from post-germination barley, while its pre-germination capacity was 5.44 mg AA eq/g sample. The post-germination oats ethanol extract had a higher antiproliferation effect on HepG2 and HCT-116 cell lines than the pre-germination extract. The cell viability of the HepG2 and HCT-116 cell lines exposed to the post-germination oats was 19.98 and 11.81% at 3.0 mg/mL, respectively. 相似文献
999.
The goal of this study was to develop a high value Korean traditional rice wine possessing the antihypertensive functionality. The effects of the Lycii fructus and Pholiota adiposa on the alcohol fermentation and its angiotensin I-converting (ACE) inhibitory activity of Korean traditional rice wine, yakju were investigated. Optimal fermentation conditions for the preparation of yakju consisted of the koji added at 10% and a fermentation period of 10 days at 25?C. The best acceptability appeared with the Lf-1 traditional rice wine that was brewed by the addition of 1% Lycii fructus into the mash containing cooked rice, koji and antihypertensive S. cerevisiae. Its antihypertensive ACE inhibitory activity was 76%. Its ACE inhibitory activity was also increased about 8% by the addition of 0.1% of the edible mushroom Pholiota adiposa ASI 24012 fruiting bodies into the mash, showing good sensory characteristics. From these results, Lf-Pa1 yakju which was brewed by addition of 1% Lycii fructus and 0.1% Pholiota adiposa into the mash, has the potential to become a new functional Korean traditional rice wine with high antihypertensive properties. 相似文献
1000.
Magda Corgneau Claire Gaiani Jeremy Petit Yoana Nikolova Sylvie Banon Léa Ritié-Pertusa Doan Thanh Lam Le Joël Scher 《International Journal of Food Science & Technology》2019,54(6):2132-2140
Influence of diverse botanical sources (wheat, maize, waxy maize, cassava, potato, rice or waxy rice) on in vitro native starch digestibility has been investigated. Physicochemical properties (chemical composition, particles size and shape, surface features) of starch granules were determined with a view to explaining digestibility differences between samples. Rapidly digestible starch (RDS), slowly digestible starch (SDS) and resistant starch (RS) contents were measured according to Englyst method. Potato starch was shown to be composed of large rounded granules having smooth surfaces, which explains its slow enzymatic breakdown. Potato starch displayed the highest RS (86%) content and the lowest RDS content (9.9%). Since RS positively influences health and SDS may result in cell, tissue and/or organ damages, potato starch is an ideal starch nutrient. Conversely, waxy rice starch was rich in amylopectin and displayed small diameters and angular shapes, which are both known to facilitate enzymatic starch hydrolysis. It exhibited a near-zero RS content (0.9%) and a high RDS fraction (60%). According to this study, potato starch exhibited the best nutrient profile, followed up in this order by cassava, waxy maize, wheat, maize and waxy rice starches. 相似文献