• Bulletin of the Korean Chemical Society
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• v.23 no.5
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• pp.693-698
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• 2002

A method has been described for the determination of Cu(Ⅱ), Pb(Ⅱ), Ni(Ⅱ), Cd(Ⅱ), Mn(Ⅱ) and Fe(Ⅲ) by flame atomic absorption spectrometry (FAAS) after preconcentration on Amberlite XAD-16 resin, using hexamethyleneammonium-hexamethylenedithiocarbamate (HMA-HMDTC) as a chelating agent, and NH3/NH4Cl buffer solution (pH 9). Influences of various analytical parameters such as pH, concentration of nitric acid, amount of analytes, diverse ions and sample volume were investigated. The relative standard deviation (RSD) and the detection limit (LOD) were found in the range of 0.8-2.9% and 0.006-0.277 ㎍/mL,respectively. Recoveries obtained by the column method were quantitative ( >95%) at optimum conditions.The method was applied to the determination of some metal ions in seawater and wastewater samples. A high preconcentration factor (about 150 for seawater and 75 for wastewater samples) and simplicity are the main advantages of this suggested method.

• Analytical Science and Technology
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• v.11 no.4
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• pp.243-247
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• 1998

Cisplatin is a platinum-containing antitumor agent with nephrotoxic and neurotoxic side effects. An analytical method for measuring cisplatin in plasma by FAAS was developed, which is rapid, simple and need no sample preparation. The linearity test of calibration curve in the range of 20~1000 ng/mL showed good correlation coefficient of r=0.999. The result of accuracy test appeared to be relative standard deviation of < 5.0% at concentration range from 50 to 1000 ng/mL. When $200{\mu}L$ of plasma was used, detection limit was 10 ng/mL. Therefore, it can be applied for the monitoring in plasma for optimal condition of treatment and reduce of toxicity.

• Bulletin of the Korean Chemical Society
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• v.32 no.2
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• pp.444-450
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• 2011

A novel method that utilizes poly(5-methyl-2-thiozyl methacrylamide-co-2-acrylamido-2-methyl-1-propanesulfonic acid-co-divinylbenzene) [MTMAAm/AMPS/DVB] as a solid-phase extractant was developed for simultaneous preconcentration of trace Cd(II), Co(II), Cr(III), Cu(II), Fe(III), Mn(II), Ni(II), Pb(II), and Zn(II) prior to the measurement by flame atomic absorpiton spectrometry (FAAS). Experimental conditions for effective adsorption of the metal ions were optimized using column procedures. The optimum pH value for the simultaneously separation of the metal ions on the new adsorbent was 2.5. Effects of concentration and volume of elution solution, sample flow rate, sample volume and interfering ions on the recovery of the analytes were investigated. A high preconcentration factor, 100, and low relative standard deviation values, $\leq$1.5% (n = 10), were obtained. The detection limits (${\mu}gL^{-1}$) based on the 3s criterion were 0.18 for Cd(II), 0.11 for Co(II), 0.07 for Cr(III), 0.12 for Cu(II), 0.18 for Fe(III), 0.67 for Mn(II), 0.13 for Ni(II), 0.06 for Pb(II), and 0.09 for Zn(II). The validation of the procedure was performed by the analysis of two certified reference materials. The presented method was applied to the determination of the analytes in various environmental samples with satisfactory results.

• Journal of Animal Science and Technology
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• v.65 no.1
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• pp.57-68
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• 2023

Flavor is an important sensory trait of chicken meat. The free amino acid (FAA) and nucleotide (NT) components of meat are major factors affecting meat flavor during the cooking process. As a genetic approach to improve meat flavor, we performed a genome-wide association study (GWAS) to identify the potential candidate genes related to the FAA and NT components of chicken breast meat. Measurements of FAA and NT components were recorded at the age of 10 weeks from 764 and 767 birds, respectively, using a White leghorn and Yeonsan ogye crossbred F2 chicken population. For genotyping, we used 60K Illumina single-nucleotide polymorphism (SNP) chips. We found a total of nine significant SNPs for five FAA traits (arginine, glycine, lysine, threonine content, and the essential FAAs and one NT trait (inosine content), and six significant genomic regions were identified, including three regions shared among the essential FAAs, arginine, and inosine content traits. A list of potential candidate genes in significant genomic regions was detected, including the KCNRG, KCNIP4, HOXA3, THSD7B, and MMUT genes. The essential FAAs had significant gene regions the same as arginine. The genes related to arginine content were involved in nitric oxide metabolism, while the inosine content was possibly affected by insulin activity. Moreover, the threonine content could be related to methylmalonyl-CoA mutase. The genes and SNPs identified in this study might be useful markers in chicken selection and breeding for chicken meat flavor.

• Korean Journal of Food Science and Technology
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• v.31 no.1
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• pp.13-19
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• 1999

In order to investigate the composition and the actual status of extractive nitrogenous compounds in the fresh 'Gae-bul' (echiuroid), a kind of echiurida (Urechis unicinctus), the extract was analyzed separately into extractive nitrogen, free amino acids (FAAs), oligopeptides, nucleotides and related compounds, quaternary ammonium bases, and guanidino compounds, using specimens collected at fish market in April 1988. The extractive nitrogen of echiuroid was $601{\sim}610mg/100g$. Thirty-two kinds of FAAs were found, and the total of them in it was $2,437{\sim}2,609\;mg$. Glycine, alanine, taurine, and serine were the major FAAs in the echiuroid extracts. The large amount of glycine $(1,075{\sim}1,171mg)$ was noted in the extract. The sum of ATP and its related compounds was $3.04{\sim}3.12\;{\mu}mol/g$, and predominant compound was the AMP. Besides, CTP, GTP, UTP and their related compounds were also detected, and the total amount of them was $1.92{\sim}3.74\;{\mu}mol/g$. The lower homarine, trigonelline, TMAO, TMA, and creatine were detected in the extracts. The extractive nitrogenous constituents of medium size and large size echiuroid were almost the same level each other. The total nitrogens of the compounds analyzed for each samples accounted for more than 90% of the extractive nitrogen in this study.

• Journal of Nutrition and Health
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• v.52 no.2
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• pp.149-156
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• 2019

Purpose: The skin pH is maintained by epidermal lactate, free fatty acids (FFAs), and free amino acids (FAAs). As a significant determinant of skin health, the skin pH is increased (less acidic) under abnormal and aged skin conditions. In a search for dietary alternatives that would promote an acidic skin pH, this study investigated the dietary effects of Lactobacillus plantarum CJLP55 isolated from Korean kimchi on the skin pH, and epidermal levels of lactate, FFAs, and FAAs in adult subjects. Methods: Seventy eight subjects (mean age $24.9{\pm}0.5years$, range 19 ~ 37 years) were assigned randomly to ingest CJLP55, Lactobacillus strain from kimchi, (n = 39, CJLP group) or placebo supplements (n = 39, placebo group) for 12 weeks in a double-blind, placebo-controlled trial. Skin pH and epidermal levels of lactate, FFAs and FFAs were assessed at 0, 6 and 12 weeks. Results: Although significant decreases in skin pH were observed in both the CJLP and placebo groups at 6 weeks, the skin pH was decreased significantly only in the CJLP group at 12 weeks. In parallel, the epidermal level of lactate in the CJLP group was also increased by 25.6% at 12 weeks. On the other hand, the epidermal level of FAAs were not altered in the CJLP and placebo groups, but the epidermal level of total FFAs, including palmitic acid and stearic acid, was lower in the CJLP group than in the placebo group over 12 weeks. The changes in the other FFAs, such as palmitoleic acid and oleic acid, were similar in the CJLP and placebo groups over 12 weeks. Conclusion: Overall, a dietary supplement of CJLP55 promotes acidic skin pH with a selective increase in epidermal lactate in adult subjects.

• Bulletin of the Korean Chemical Society
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• v.27 no.9
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• pp.1293-1296
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• 2006

In this study, a solid phase extraction method has been developed for the preconcentration and separation of the elements Cr(III), Fe(III), Co(II) and Pb(II) at trace levels by using a column packed with Amberlite XAD-1180 resin loaded with 4-(2-pyridylazo)-resorcinol (PAR) reagent. After preconcentrating, the metals retained on the column were eluted with 20 mL of 3 mol/L $HNO_3$ and then determined by flame atomic absorption spectrometry (FAAS). The factors affecting the recovery of the elements, such as pH, type and concentration of eluent, volume of sample and elution solution, and matrix components, were also ascertained. The recoveries of Cr(III), Fe(III), Co(II) and Pb(II) were found to be $99\;{\pm}\;4,\;97\;{\pm}\;3,\;95\;{\pm}\;3$ and $98\;{\pm}\;4$%, respectively, under the optimum conditions at 95% confidence level and the relative standard deviations found by analyzing of nine replicates were $\leq4.4$%. The preconcentration factors for Cr(III), Fe(III), Co(II) and Pb(II) were found as 75, 125, 50 and 75 respectively. The detection limits (DL, 3s/b) were 3.0 $\mu g/L$ for Cr(III), 1.25 $\mu g/L$ for Fe(III), 3.3 $\mu g/L$ for Co(II), and 7.2 $\mu g/L$ for Pb(II). The recoveries achieved by adding of metals at known concentrations to samples and the analysis results of Buffalo river sediment (RM 8704) show that the described method has a good accuracy. The proposed method was applied to tap water, stream water, salt and street dust samples.

• Safety and Health at Work
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• v.3 no.3
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• pp.216-223
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• 2012

Objectives: The objectives of this study were to determine the lead levels in blood samples from nielloware workers, to determine airborne lead levels, to describe the workers' hygiene behaviors, and to ascertain and describe any correlations between lead levels in blood samples and lead levels in airborne samples. Methods: Blood samples and airborne samples from 45 nielloware workers were collected from nielloware workplaces in Nakhon Sri Thammarat Province, Thailand. Lead levels were determined by flame atomic absorption spectrometry (FAAS), at a wavelength of 283.3 nm. FAAS was used especially adequate for metals at relatively high concentration levels. Results: The geometric mean of the 45 airborne lead levels was 81.14 ${\mu}g/m^3$ (range 9.0-677.2 ${\mu}g/m^3$). The geometric mean blood lead level of the 45 workers was 16.25 ${\mu}g/dL$ (range 4.59-39.33 ${\mu}g/dL$). No worker had a blood lead level > 60 ${\mu}g/dL$. A statistically significantly positive correlation was found between airborne lead level and blood lead levels (r = 0.747, p < 0.01). It was observed that personal hygiene was poor; workers smoked and did not wash their hands before drinking or eating. It was concluded that these behaviors had a significant correlation with blood lead levels (p < 0.001). Conclusion: Improvements in working conditions and occupational health education are required due to the correlation found between blood leads and airborne lead levels.

• Analytical Science and Technology
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• v.14 no.3
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• pp.253-258
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• 2001

This is a research on hazardous characteristics and potentials of bottom ash from 9 municipal solid waste combustors(200 tons/day) of Korea by the test methods of leaching and content. The leaching method was performed by Waste Test Method of Korea. In case of the content method, mercury was determined by thermal decomposition amalgamation atomic absorption spectrometer, other 9 elemets including Pb, which were pretreated by U.S.EPA SW-846 3050B method, were determined by flame atomic absorption spectrometer(FAAS) or inductively coupled plasma atomic emission spectrometer(ICP-AES). Results of leaching test showed that Pb and Cu was main pollutants. It was interested that the distribution rate of metals' contents of each combustors was similar and the rank of concentration was Fe>Zn>Cu>Mn>Pb>Cr>As>Cd>Hg.

• Food Science of Animal Resources
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• v.40 no.6
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• pp.908-923
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• 2020

The objective of this study was to compare tastes-related components and eating quality properties between Hanwoo steer and cow meats. Longissimus thoracis (LT) muscles with same quality grade (1⁺ grade) collected from left sides of the steer and cow carcasses were used for analyses of technological quality traits, free amino acids (FAAs), metabolites, nucleotides, fatty acids and sensory attributes. there were no differences occurring in the chemical composition (fat, protein, moisture and collagen) and technological quality traits (cooking loss, water holding capacity, shear force and color) between the two beef types (p>0.05). The cow meat exhibited significantly higher amounts of some FAAs associated with umami (e.g., glutamic acid and lysine), sweetness (e.g., proline and glutamic acid) and saltiness (e.g., histidine and glutamic acid) compared to the steer meat (p<0.05). Regarding the nucleotides, no differences occurred in all the identified nucleotides between the two beef types (p>0.05). A total of 27 metabolites were identified, however, only some compounds (e.g., acetate, creatine, creatinine, glucose and inosine, etc.) showed their significantly higher amounts in the cow meat compared with those in the steer meat (p<0.05). In terms of sensory aspects, the panelists found no differences in scores of all the eating quality traits between the two sex types of beef (p>0.05). Overall, excepts some variations in tastes-active compounds, there were no differences in the quality characteristics in general and eating quality in particular between the cow and steer meats when they were in the same quality grade.