• Korean Journal of Food Science and Technology
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• v.39 no.1
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• pp.25-28
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• 2007

A survey of total aflatoxin levels was conducted on 565 food samples (cereals, nuts, etc) collected in commercial markets. The determination of aflatoxins ($B_{1}$, $B_{2}$, $G_{1}$ and $G_{2}$) was performed using HPLC with fluorescence detector. The Limit of Detections (LODs) of the B group and G group were 0.05 ng/g and 0.07 ng/g, respectively. In addition, recoveries of rice, peanut butter, and red pepper flour were satisfactory. Total aflatoxin was detected 27 samples(4.8%) out of 565 samples. Incidence ratios in cereals, nuts, processed products, and other foods were 0.2, 0.4, 3.0 and 1.2%, respectively, but aflatoxin was not detected in pulse and dried fruits. The daily intake of total aflatoxin using food intakes was 0.04 ng/kg bw/day.

• Journal of the Korean Society of Food Science and Nutrition
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• v.36 no.10
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• pp.1229-1234
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• 2007

Antioxidant activities of extracts from anglerfish (Lophiiu Zitulon) were evaluated. Each part of fresh (skin, flesh, stomach, and liver) or dried (skin and flesh) anglerfish was extracted by four different solvents (methanol, ethanol, acetone, and distilled water). Antioxidant activities of the extracts were determined by radical scavenging activity (RSA) and reducing power (RP). Relatively higher RSA and RP were found in methanol and water extract of fresh anglerfish liver. Antigenotoxic effect of the extracts, which was measured by Comet assay, was shown in most of the extracts except methanol, acetone and distilled water extracts of fresh stomach sample. These results indicated that antioxidant and antigenotoxic properties of extracts from angler fish were variable depending on parts, solvent, and/or physicochemical state. The appropriate extraction process could provide some valuable bioactive materials from anglerfish.

• Journal of Microbiology and Biotechnology
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• v.19 no.12
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• pp.1656-1664
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• 2009

Bioaugmentation of bioreactors focuses on the removal of numerous organics, with little attention typically paid to the maintenance of high and stable nitrite accumulation in partial nitrification. In this study, a bioaugmented membrane bioreactor (MBR) inoculated with enriched ammonia-oxidizing bacteria (AOB) was developed, and the effects of dissolved oxygen (DO) and temperature on the stability of partial nitrification and microbial community structure, in particular on the nitrifying community, were evaluated. The results showed that DO and temperature played the most important roles in the stability of partial nitrification in the bioaugmented MBR. The optimal operation conditions were found at 2-3 mgDO/l and $30^{\circ}C$, achieving 95% ammonia oxidization efficiency and nitrite ratio ($NO_2^-/{NO_x}^-$) of 0.95. High DO (5-6 mg/l) and low temperature ($20^{\circ}C$) had negative impacts on nitrite accumulation, leading to nitrite ratio drop to 0.6. However, the nitrite ratio achieved in the bioaugmented MBR was higher than that in most previous literatures. Denaturing gradient gel electrophoresis (DGGE) and fluorescence in situ hybridization (FISH) were used to provide an insight into the microbial community. It showed that Nitrosomonas-like species as the only detected AOB remained predominant in the bioaugmented MBR all the time, and coexisted with numerous heterotrophic bacteria. The heterotrophic bacteria responsible for mineralizing soluble microbial products (SMP) produced by nitrifiers belonged to the Cytophaga-Flavobacterium-Bacteroides (CFB) group, and $\alpha$-, $\beta$-, and $\gamma$- Proteobacteria. The fraction of AOB ranging from 77% to 54% was much higher than that of nitrite-oxidizing bacteria (0.4-0.9%), which might be the primary cause for the high and stable nitrite accumulation in the bioaugmented MBR.

• Journal of Pharmaceutical Investigation
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• v.36 no.5
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• pp.331-338
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• 2006

A rapid, selective and sensitive reverse-phase HPLC methods for the determination of atenolol and chlorthalidone in human serum and whole blood were validated, and applied to the pharmacokinetic study of atenolol and chlorthalidone combination therapy. Atenolol and an internal standard, pindolol, were extracted from human serum by liquid-liquid extraction, and analyzed on a $\mu$-Bondapak C18 $10-{\mu}$ column in a mobile phase of methanol-0.01 M potassium dihydrogenphosphate(30:70, v/v, adjusted to pH 3.5) and fluorescence detection(emission: 300 nm, excitation: 224 nm). Chlorthalidone and an internal standard, probenecid, were extracted form human whole blood by liquid-liquid extraction, and analyzed on a Luna C18 $5-{\mu}$ column in a mobile phase of acetonitrile containing 77% 0.01 M sodium acetate and UV detection at 214 nm. These analysis were performed at three different laboratories using the same quality control(QC) samples. The chromatograms showed good resolution, sensitivity, and no interference by human serum and whole blood, respectively. The methods showed linear responses over a concentration range of 10-1,000 ng/mL for atenolol and 0.05-20 ${\mu}g/mL$ for chlorthalidone, with correlation coefficients of greater than 0.999 at all the three laboratories. Intra- and inter-day assay precision and accuracy fulfilled international requirements. Stability studies(freeze-thaw, short-, long-term, extracted sample and stock solution) showed that atenolol and chlorthalidone were stable. The lower limit of quantitation of atenolol and chlorthalidone were 10 ng/mL and 0.05 ${\mu}g/mL$, respectively, which was sensitive enough for pharmacokinetic studies. These methods were applied to the pharmacokinetic study of atenolol and chlorthalidone in human volunteers following a single oral administration of Hyundai $Tenoretic^{\circledR}$ tablet(atenolol 50 mg and chlorthalidone 12.5 mg) at three different laboratories.

• Journal of Pharmaceutical Investigation
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• v.31 no.4
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• pp.281-287
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• 2001

Rebamipide is a novel anti-gastric ulcer agent that has been reported to increase the synthesis of mucus, to increase the mucosal concentration of prostaglandin, and to promote rapid ulcer healing. The purpose of the present study was to evaluate the bioequivalence of two rebamipide tablets, $Mucosta^{TM}$ (Otsuka Korea Pharmaceutical Co., Ltd.) and $Rebamide^{TM}$ (Kyung Dong Pharmaceutical Co., Ltd.), according to the guidelines of Korea Food and Drug Administration (KFDA). The rebamipide release from the two rebamipide tablets in vitro was tested using KP VII Apparatus II method at pH 6.8 dissolution media. Twenty normal male volunteers, $24.20{\pm}2.26$ years in age and $66.19{\pm}9.41\;kg$ in body weight, were divided into two groups and a randomized $2{\times}2$ cross-over study was employed. After one tablet containing 100 mg of rebamipide was orally administered, blood was taken at predetermined time intervals and the concentrations of rebamipide in serum were determined using HPLC method with fluorescence detector. The dissolution profiles of two rebamipide tablets were very similar at pH 6.8 dissolution media. Besides, the pharmacokinetic parameters such as $AUC_t$, $C_{max}\;and\;T_{max}$ were calculated and ANOVA test was utilized for the statistical analysis of the parameters. The results showed that the differences in $AUC_t$, $C_{max}\;and\;T_{max}$ between two tablets based on the $Mucosta^{TM}$ were -2.57%, 5.77% and -1.47%, respectively. Minimum detectable differences $({\Delta})$ at ${\alpha}=0.05$ and $1-{\beta}=0.8$ were less than 20% (e.g., 12.62% and 17.63% for $AUC_t,\;and\;C_{max}$, respectively). The powers $(1-{\beta})$ at ${\alpha}=0.05$, ${\Delta}=0.2$ for $AUC_t\;and\;C_{max}$ were above 99.00% and 88.56%, respectively. The 90% confidence intervals were within ${\pm}20%$ (e.g., $-9.96{\sim}4.82$ and $-4.54{\sim}16.09$ for $AUC_t\;and\;C_{max}$, respectively). Two parameters met the criteria of KFDA for bioequivalence, indicating that $Rebamide^{TM}$ tablet is bioequivalent to $Mucosta^{TM}$ tablet.

• Korean Journal of Food Science and Technology
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• v.41 no.2
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• pp.157-161
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• 2009

This paper proposes an analytical method for determining amounts of polycyclic aromatic hydrocarbons (PAHs; benzo[a]anthracene, chrysene, benzo[b]fluoranthene, benzo[k]fluoranthene, benzo[a]pyrene, dibenzo[a,h]anthracene, benzo[g,h,i] perylene) in coffees beans. Soxhlet extraction and liquid/liquid extraction were tested for the quantification of seven PAHs. Soxhlet extraction was followed by cyclohexane extraction and used a silica cartridge. Liquid/liquid extraction was followed by n-hexane extraction and utilized a florisil cartridge. The extracts were analyzed by HPLC-fluorescence detection (FLD) with a Supelcosil LC-PAH column. The PAH recoveries ranged from 78.68 to 96.28% for the liquid/liquid extraction, and from 67.47 to 84.60% for the Soxhlet extraction.

• YAKHAK HOEJI
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• v.47 no.5
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• pp.339-344
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• 2003

Atenolol is a water soluble, ${\beta}_1$ selective adrenoceptor antagonist used in the treatment of angina and hypertension. It is primarily eliminated renally with minimal hepatic metabolism. The purpose of the present study was to evaluate the bioequivalence of Samchundang Atenolol (Samchundang Pharmaceutical Co., Korea.) to Tenolmin(Hyundai Pharmaceutical Ind. Co., Korea). The atenolol release from the two atenolol tablets in vitro was tested using KP VII Apparatus II method with various different kinds of dissolution media (pH 1.2, 4.0, 6.8 buffer solution and water). Twenty four normal male volunteers, 22.83$\pm$1.99 years in age and 65.82$\pm$7.15 kg in body weight, were divided into two groups and a randomized $2{\times}2$ cross-over study was employed. After one tablet containing 50 mg of atenolol was orally administered, blood was taken at predetermined time intervals and the concentrations of atenolol in serum were determined using HPLC method with fluorescence detector. The dissolution profiles of two atenolol tablets were very similar at all dissolution media. Besides, the pharmacokinetic parameters such as $AUC_{t}$, $C_{max}$ and $T_{max}$ were calculated and ANOVA test was utilized for the statistical analysis of the parameters using logarithmically transformed $AUC_{t}$ and $C_{max}$ and untransformed $T_{max}$. The results showed that the differences in $AUC_{t}$, $C_{max}$ and $T_{max}$ between two tablets based on the Tenolmin were 3.74％, 4.38％ and 17.77％, respectively. There were no sequence effects between two tablets in these parameters. The 90％ confidence intervals using logarithmically transformed data were within the acceptance range of log(0.8) to log(1.25) (e.g., log(0.98)∼log(1.l1) and log(0.95)∼log(1.l5) for $AUC_{t}$ and $C_{max}$ respectively), indicating that Samchundang Atenolol tablet is bioequivalent to Tenolmin tablet.

• Journal of fish pathology
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• v.9 no.1
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• pp.65-77
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• 1996

Tachyplesin I is an antimicrobial peptide isolated from horseshoe crab. To investigate the mechanism of action of tachyplesin I for phospholipid bilayers, tachyplesin I and five analogs have been synthesized by the solution method. The synthesized five analogs are [$Phe^2$]-tachyplesin I, [$Phe^{8,13}$]-tachyplesin I, [$Cys(Acm)^{3,7,12,16}$]-tachyplesin I with no disulfide bonds, 7(Acm) and 10 (Acm) which denote the fragments [$Cys(Acm)^{3,7,12,16}$]-tachyplesin I. Circular dichroism spectra showed that tachyplesin I took an antiparallel $\beta$-structure in buffer solution and a less ordered structure in acidic liposomes. The carboxyfluorescein leakage experiment indicated that tachyplesin I interacted strongly with neutral and acidic phospholipid bilayers. In fluorescence experiment, the hydrophobic part of the peptide was shown to be embedded in lipid bilayers. All the peptides except for 7(Acm) and 10(Acm) were almost equally active in lipopolysaccharide binding. Therefore, the present study suggested that phospholipid bilayers induced a conformational change of tachyplesin I from the stable $\beta$-structure to a less ordered one.

• Korean Journal of Food Science and Technology
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• v.44 no.4
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• pp.460-466
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• 2012

Through an analysis of T-2 and HT-2 toxins in corn and brown rice, the effect of enzymatic deacetylation of T-2 toxin on HT-2 toxin was investigated. Gas chromatography (GC) with electron capture detection and high-performance liquid chromatography (HPLC) with fluorescence detection were used for quantitative determination. T-2 toxin was converted into HT-2 (84-86%) within 15 min in the presence of crude protein extracts from corn and brown rice. The absence of T-2 conversion was observed for autoclaved samples, in which the enzymes were inactivated. When phosphate buffered saline, followed by methanol, was used as the extraction solvent, recoveries of T-2 toxin spiked at 50 and 200 ${\mu}g/kg$ were from 60 to 87%, whereas those of HT-2 in the autoclaved samples were 0%. In non-autoclaved samples, recoveries of HT-2 were 37-66%, whereas those of T-2 were negligible. However, the conversion of T-2 into HT-2 was not observed when samples were extracted by methanol/water.

• Journal of Food Hygiene and Safety
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• v.32 no.3
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• pp.187-192
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• 2017

The consumption of herbal medicines has been increasing with growing interest in health. However, due to recent climate change and the complex distribution process of herbal medicines with high import dependence the likelihood of contamination with mycotoxin has been increased. Mycotoxins are emerging as key indicators for ensuring safety of herbal medicines. A total of 498 herbal medicine samples were screened for mycotoxin contamination in this study. Aflatoxin in the herbal medicine samples was extracted by using immunoaffinity column, then the extracted aflatoxin was quantified via high performance liquid chromatography coupled with fluorescence detection (HPLC-FLD) method. The extraction method was verified by linearity, recovery, LOD and LOQ. Aflatoxins were detected in 39/498 samples in an average of $7.670{\mu}g/kg$ ($0.610-77.452{\mu}g/kg$ range). Although safety standards for Corydalis Tuber is not currently available in korea, five of the 39 samples had high concentration of aflatoxins (average of $14.9{\pm}4.1{\mu}g/kg$). In conclusion, it is urgent to establish safety criteria of aflatoxin in Corydalis Tuber. The results of the current study suggest that continuous monitoring is necessary for proactive management of herbal medicine safety.