• Economic and Environmental Geology
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• v.27 no.5
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• pp.469-477
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• 1994

Many researchers have investigated most representative sequential extraction method using various reagents for determining the chemical forms of metals in soils and sediments. In this paper, a newly modified method for sequential extraction scheme based on Tessier's method by Environmental Geochemistry Research, Centre for Environmental Technology, Imperial College, was introduced and examined. In comparison with Tessier's method, originally designed for sediment analysis by Atomic Absorption Spectrophotometry (AAS), the sequential extraction scheme has been developed for the multi-element analysis by Inductively Coupled Plasma Atomic Emission Spectrometry (ICP-AES). The partitioning of particulate trace elements was classified into five fractions: (i) exchangeable, (ii) bound to carbonates or specially adsorbed, (iii) bound to Fe and Mn oxides, (iv) bound to organic matter and sulphides and (v) residuals. The experimental results of the pilot study for in-house reference material (HRM2) and certified international standard reference material (SRM2711) using the modified method showed not only reasonable precision and accuracy but also acceptable overall recovery rates. In addition, mine dump soils sampled in the Dalsung Cu-W mine, Korea were prepared and sequentially extracted using the method. Most of Cu was bound to organic matter/sulphides and residual fractions. The dominant fraction of soil Pb and Zn in the study area was found in the residuals. The fraction of Cd showed a wide variation between samples and could be found bound to the carbonates or specially adsorbed, oxides, organic fraction and residuals. The recovery rates of Cd, however, were poor due to relatively low Cd concentrations in soils. The heavy metals in these mine dumps appear to be in the more inert forms and should not be readily bioavailable. The soils, however, had very low pH values (average 4.1) and had sandy textures; consequently, rapid infiltration of rainfall may increase leaching of Zn and Cd which were found to be around 5 to 10% of the exchangeable fraction. As a result of the investigation of this study, it has been strongly recommended that these mine waste materials should still be considered a significant contaminant source and will need environmental remediation to prevent pollutants from being released into the environment.

• Korean Journal of Soil Science and Fertilizer
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• v.41 no.3
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• pp.184-189
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• 2008

To assess the relationship between Cd fraction in paddy soils and Cd in polished rice, soils and rice were analyzed at the 3 Cd contaminated paddy fields near closed mines. Major Cd fractions of A field were organically bound (62.6%) and Fe-Mn oxide bound (25.3%) forms. In case of B field, major Cd fractions of B1 field were carbonate bound (46.3%) and Fe-Mn oxide bound (31.6%) form whereas B2 field were residual (54.3%) and carbonate bound (21.8%) form, respectively. It showed a huge difference of Cd fraction each other. 0.1M HCl extractable Cd in soil was positively correlated with Cd in rice. Specially, the ratios of 0.1M HCl extractable Cd against total Cd content in soils were 13.7%, 2.6%, and 0.45% in A, B1, and B2 fields, respectively. These ratio were largely affected with Cd uptake to rice grain. Also, exchangable, Fe-Mn oxide bound, and carbonate bound form, which are partially bioavailable Cd fraction to the plant, were positively correlated with Cd in rice while organically bound and residual form was not correlated. Multiple regression equation was developed with Rice Cd = -0.02861 + 0.07456 FR 1(exchangeable) + 0.00252 FR 2(carbonate bound) + 0.001075 FR 3(Fe Mn oxide bound) - 0.00095 FR 4(organically bound) - 0.00348 FR 5(residual) ($R^2=0.7893^{***}$) considering Cd fraction in soils.

• Ocean and Polar Research
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• v.32 no.3
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• pp.177-186
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• 2010

A sequential extraction technique was used to study sediment phosphorus speciation and its relative importance in the intertidal flat of Keunso Bay during summer and winter for a better understanding of the phosphorus cycle and bioavailability in intertidal sediments. Loosely sorbed P contents were the lowest among the five P-pools and showed little seasonal or spatial variation. Although Fe-bound P contents were almost constant in winter, they decreased rapidly with sediment depth in summer. The dissolution of Fe oxides, used as an oxidant for the anaerobic respiration, ascribed the rapid decrease of Fe-bound P in summer. Al-bound P contents displayed little seasonal variation, but showed a large spatial variation, with higher values in the upper intertidal flat. Comprising about 50% of total P, Ca-bound P contents were the highest among the five P-pools. Ca-bound P contents were higher in winter than summer, but did not exhibit a clear spatial variation. Organic P contents were higher in summer than winter, which was associated with higher primary production and clam biomass in summer. Organic P contents were higher in the lower intertidal flat than the upper intertidal flat. In Keunso Bay, bioavailable P contents of the intertidal flat comprising about one third of total P ranged from 2.41 to 5.09 ${\mu}molg^{-1}$ in summer and 3.82 to 5.29 ${\mu}molg^{-1}$ in winter. The bioavailability of P contents was higher in the lower intertidal flat than the upper intertidal flat, which was attributed to the large clam production in the lower intertidal flat.

• Journal of Microbiology and Biotechnology
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• v.25 no.4
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• pp.469-478
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• 2015

In spite of the reported probiotic effects, Bifidobacterium bifidum BGN4 (BGN4) showed no βglucosidase activity and failed to biotransform isoflavone glucosides into the more bioactive aglycones during soy milk fermentation. To develop an isoflavone-biotransforming BGN4, we constructed the recombinant B. bifidum BGN4 strain (B919G) by cloning the structural β-glucosidase gene from B. lactis AD011 (AD011) using the expression vector with the constitutively active promoter 919 from BGN4. As a result, B919G highly expressed β-glucosidase and showed higher β-glucosidase activity and heat stability than the source strain of the β-glucosidase gene, AD011. The biotransformation of daidzin and genistin compounds using the crude enzyme extract from B919G was completed within 4 h, and the bioconversion of daidzin and genistin in soy milk during fermentation with B919G also occurred within 6 h, which was much faster and higher than with AD011. The incorporation of this β-glucosidase-producing Bifidobacterium strain in soy milk could lead to the production of fermented soy milk with an elevated amount of bioavailable forms of isoflavones as well as to the indigenous probiotic effects of the Bifidobacterium strain.

• Archives of Pharmacal Research
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• v.26 no.1
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• pp.89-94
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• 2003

In vivo clearance of BMS-182874 was primarily due to metabolism via stepwise N-demethylation. Despite in vivo clearance approached ca 50％ of the total liver plasma flow, BMS-182874 was completely bioavailable after oral administration in rats. Saturable first-pass metabolism and the role of extrahepatic tissue were evaluated as possible reasons for complete oral bioavailability despite extensive metabolic clearance. Pharmacokinetic parameters were obtained after an intravenous and a range of oral doses of BMS-182874 in rats. Bile and urine were collected from bile-duct cannulated (BDC) rats and the in vivo metabolic pathways of BMS-182874 were evaluated. Pharmacokinetics of BMS-182874 were also compared in nephrectomized (renally impaired) vs. sham-operated control rats. Oral bioavailability of BMS-182874 averaged 100％, indicating that BMS-182874 was completely absorbed and the first-pass metabolism (liver or intestine) was negligible. The AUC and C/sub max/ values increased dose-proportionally, indicating kinetics were linear within the oral dose range of 13 to 290 mmole/kg. After intravenous administration of BMS-182874 to BDC rats, about 2％ of intact BMS-182874 was recovered in excreta, indicating that BMS-182874 was cleared primarily via metabolism in vivo. The major metabolite circulating in plasma was the mono-N-desmethyl metabolite and the major metabolite recovered in excreta was the di-N-desmethyl metabolite. In vivo clearance of BMS-182874 was significantly reduced in nephrectomized rats. These observations suggest saturable first-pass metabolism is unlikely to be a mechanism for complete oral bioavailability of BMS-182874. Reduced clearance observed in the nephrectomized rats suggests that extrahepatic tissues (e.g., kidneys) may play an important role in the in vivo clearance of xenobiotics that are metabolized via N-demethylation.

• Journal of Preventive Medicine and Public Health
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• v.34 no.1
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• pp.41-46
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• 2001

Objectives : To investigate the effects of particulate matter (PM), a marker of environmental pollution derived from combustion sources, on lung epithelial cells (A549) and macrophage (RAW 264.7). Methods : The production of reactive radicals from lung cells, the lipid peroxidation of cell membrane, and the cytotoxicity of PM were measured using an in vitro model. The results were compared with a control group. Results : The presence of PM significantly increased the production of reactive oxygen species and reactive nitrogen species with time and in a dose dependent pattern and also increased the malondialdehyde concentration in lung epithelial cells. The cytotoxicity of PM was increased with increasing concentration of PM. Conclusions : It has been suggested that urban particulate matter causes an inflammatory reaction in lung tissue through the production of hydroxyl radicals, nitric oxides and numerous cytokines. The causal chemical determinant responsible for these biologic effects are not well understood, but the bioavailable metal in PM seems to determine the tonicity of inhaled PM.

• Korean Journal of Soil Science and Fertilizer
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• v.46 no.2
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• pp.73-80
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• 2013

Due to the fact that possible risk associated with soil-crop-food chain transfer, metal contamination in croplands has become a major topic of wide concern. Accumulation of toxic metals in edible parts of crops grown in contaminated soils has been reported from number of crops including rice, soybean, wheat, maize, and vegetables. Therefore, in order to ensure food safety, measures are needed to be taken in mitigating metal pollution and subsequent uptake by crop plants. Present paper critically reviewed some of the cost effective remediation techniques used in minimizing metal uptake by crops grown in contaminated soils. Liming with different materials such as limestone ($CaCO_3$), burnt lime (CaO), slaked lime [$Ca(OH)_2$], dolomite [$CaMg(CO_3)_2$], and slag ($CaSiO_3$) has been widely used because they could elevate soil pH rendering metals less-bioavailable for plant uptake. Zn fertilization, use of organic amendments, crop rotation and water management are among the other techniques successfully employed in reducing metal uptake by crop plants. However, irrespectively the mitigating measure used, heterogeneous accumulation of metals in different crop species is often reported. The inconsistency might be attributed to the genetic makeup of the crops for selective uptake, their morphological characteristics, position of edible parts on the plants in respect of their distance from roots, crop management practices, the season and to the soil characteristics. However, a sound conclusion in this regard can only be made when more scientific evidence is available on case-specific researches, in particular from long-term field trials which included risks and benefits analysis also for various remediation practices.

• Journal of Nutrition and Health
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• v.50 no.3
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• pp.203-216
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• 2017

Purpose: This literature review was performed to assess the effect of raisins on human health. Methods: A review of Medline was conducted using the keywords: 'raisins, raisins and health, raisins and cardiovascular disease (CVD), raisins and cancer, raisins and diabetes, raisins and fiber, raisins and colon health, raisins and antioxidants, raisins and inflammation, raisins and dental caries'. The reference lists from previous review articles on raisins and human health and the California Raisin Marketing Board files were reviewed for additional studies. Results: Raisins have one of the highest polyphenolic content and antioxidant ORAC levels compared to other traditional dried fruits. Many of the polyphenols in raisins are well assimilated and bioavailable. Raisin consumption reduces low density lipoprotein (LDL) cholesterol, blood pressure and blood sugar, when compared to equal caloric carbohydrate snacks and is associated with a reduced risk of CVD. The anti-inflammatory and cancer chemopreventive effects of raisins are mixed. Raisin consumption reduces intestinal transit time and positively affects gut microbiota. Raisins produce sustained energy during long term athletic competitions equal to traditional sports energy gels, shots and jelly beans. Raisins produce a non-cariogenic oral environment and do not fit the American Academy of Pediatrics criteria to be considered a choking hazard. Conclusions: Based on the review of literature, consumption of raisins provide numerous health benefits for promoting general wellness and in the prevention of many chronic diseases including: CVD, type 2 diabetes mellitus (T2DM) gastrointestinal diseases, and dental caries.

• YAKHAK HOEJI
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• v.44 no.2
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• pp.182-188
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• 2000

High soy consumption leading to high exposures of soy isoflavones has been associated with a reduced risk of cancers at many sites. As part of a study focusing on the chemopreventive mechanisms, we have investigated the modulating effects of daidzein and genistein, a prominent and more bioavailable isoflavone in soy foods, on murine immune function. Daidzein (50 mg/kg) or genistein (50 mg/kg) was administered p.o. once a day for 7 days in BALB/c mice. Daidzein decreased the mitogen-stimulated proliferation of murine splenocyte, but genistein increased it. Daidzein stimulated the secretion of interleukin-4, but inhibited the secretion of ${\gamma}$-interferon, interleukin-2 and tumor necrosis factor-$\alpha$. Genistein stimulated the secretion of ${\gamma}$-interferon, interleukin-2 and tumor necrosis factor-$\alpha$, but inhibited the secretion of interleukin-4. Daidzein and geiustein inhibited the production of nitric oxide and enhanced the phagocytic activity in peritoneal macrophage. These results suggest that cancer preventive effects of daidzein is partly concerned with the secretion of $T_{H}$2 cells cytokine and the activation of macrophage phagocytosis, and genistein is partly concerned with the secretion of $T_{H}$l cells cytokine, tumor necrosis factor-$\alpha$ and the activation of macrophage phagocytosis.sis.

• Korean Journal of Soil Science and Fertilizer
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• v.43 no.6
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• pp.917-922
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• 2010

To assess the bioavailability of As in soils and to provide a basic information for adequate management of As contaminated fields, paddy soils and rice grains near 5 closed mines were collected and analyzed for As using sequential extraction procedure. The As contents extracted with 1M HCl against total As content in soils were ranged from 5.4 to 41.9% ($r=0.90^{**}$). However, these two contents of As in soils were not positively correlated with As concentration in rice grains. Major As fractionation of paddy soils was residual form ranging 38.1 to 84.1% except NS mine. Also, specially adsorbed fraction and fraction associated with amorphous Fe and Al oxyhydroxides, which are partially bioavailable As fractionation to the rice plant, were positively correlated with As in rice grains while fraction associated with crystalline Fe and Al oxyhydroxides and residual form were not correlated.