• YAKHAK HOEJI
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• v.45 no.5
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• pp.476-483
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• 2001

The clotting assay was replaced by the chromogenic substrate assay which is recommended by the European Pharmacopoeia (EP) and the Scientific and Standardization Committee of the International Society on Thrombosis and Haemostasis based on the reliability convenience and simplicity of the chromogenic assay, A correlation study was carried out with a one-stage factor Ⅷ : C clotting assay and the performance of the chromogenic assay was evaluated using two test kits that fulfilled the requirements of EP for factor Ⅷ concentrates test. Although chromogenic assay has partly differences in measurement principle and standardization, this assay has a high correlation with clotting assay in various types of factor Ⅷ concentrates and factor Ⅷ standard. We conclude that the chromogenic assay for factor Ⅷ : C concentrates correlates well with the clotting assay and shows good analytical performance.

• BMB Reports
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• v.37 no.6
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• pp.749-752
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• 2004

Saturated fatty acids are less vulnerable to lipid peroxidation than their unsaturated counterparts. In this investigation, individual fatty acids of the $C_{16}$, $C_{18}$ and $C_{20}$ families were subjected to the thiobarbituric (TBA) assay. These fatty acids were chosen based on their degree of saturation and configuration of double bonds. Interestingly, an assay threshold was reached where increasing the fatty acid concentration resulted in no additional decrease in the TBARS concentrations. Therefore, the linear range of TBARS inhibition was determined for fatty acids in the $C_{16}$ and $C_{20}$ families. The rate of TBARS inhibition was greater for the saturated than for unsaturated fatty acids, as measured from the slope of the linear range. These findings demonstrate the need to standardize the TBARS assay using multiple fatty acid concentrations when using this assay for measuring in vitro lipid peroxidation.

• Proceedings of the PSK Conference
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• 2000.04a
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• pp.175.1-175.1
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• 2000

• Korean Journal of Pharmacognosy
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• v.4 no.2
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• pp.53-58
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• 1973

• Korean Journal of Pharmacognosy
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• v.31 no.1
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• pp.82-86
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• 2000

To evaluate anti-influenza virus activity of 113 specimens of Korean traditional medicine both water and methanol extracts were examined using haemagglutination inhibition test. The water extract from Citrus junos was found to inhibit influenza virus A/Taiwan/l/86(H1N1). The survival rates of virus were determined by in situ cellular enzyme-linked immunosorbent assay. The water extract of Citrus junos was fractionated by chromatographic separating using Amberlite XAD-4, 40% MeOH and 60% MeOH layer had antiviral activity. The half inhibition concentration $(IC_{50})$ of 40% MeOH layer on survival of influenza virus was $MIC>361.5{\mu}g/ml$ and $IC_{50}$ value of fr. 40-4 fractionated from 40% MeOH layer was $677.19{\mu}g/ml$. These results suggested that the fractions of Citus junos have potent anti-influenza A virus activity.

• Journal of Pharmaceutical Investigation
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• v.33 no.4
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• pp.273-279
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• 2003

Pancreatin is a enzyme mixture breaking down carbohydrates, proteins and lipids. Most pancreatin used in Korea is imported from foreign countries. However, guideline of each country for pancreatin produced from each country is different. Therefore, guideline for pancreatin imported from several countries, such as Europe, Japan and America, it is standardized to control its quality. Assay of enzyme activity for pancreatin in KP is similar to tat in JP, but it is significantly different from those in FP ad in USP. We measured pancreatin digestive activities of 17 commercial products. Activity assay of digestive enzymes, starch- and lipid-digestive enzymes, for pancreatin by KP method (including JP) was difficult compared to those by FIP ad USP methods. Particularly, activity assays of starch- and lipid-digestive enzymes by KP method were mistakable, ad varied in diluted samples than those by FIP. However, activity assay of protein-digestive enzyme by KP method was similar to that by FIP. Starch-digestive enzyme activities of 17 commercial pancreatins by KP method were lower 0.079-fold compared to those by FIP method. Their protein-digestive enzyme activities by KP method were higher 75.7-fold than those by FIP method. Their lipid-digestive enzyme activities by KP method were lower 0.234-fold compared to those by FIP method.

• Journal of Korean Society on Water Environment
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• v.26 no.4
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• pp.574-579
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• 2010

In this study the enzyme inhibition method using dehydrogenase which has been popularly used to estimate ecotoxicity was optimized. When three bacterial strains, Escherichia coli HB101, Enterobacter asburiae KCAD-4, and Aeromonas media KCAD-13, were compared, KCAD-4 was considered as the adequate strain to estimate toxicity because of its sensitivity and reproducibility. The optimal bacterial density was estimated as $5.4{\times}10^9CFU/mL$, at which the maximum sensitivity was observed. The phosphate buffer was suitable for the reaction solution. When the reaction times required for inhibition of enzyme activity by contact of toxicants and for reaction of damaged bacteria and substrate were tested, the optimal value was estimated as 20 min and 2 hrs, respectively. It is expected that the optimized conditions can be used to develop the standardized kits to estimate ecotoxicity of heavy metals in effluent from the industrial wastewater treatment facilities.

• Toxicological Research
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• v.16 no.2
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• pp.109-116
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• 2000

The purposes of our study were to optimize the conditions of the screening and testing methods for endocrine disruptors, to characterize these assays using several compounds with well-defined endocrine activity, and to compare the sensitivity between these assays currently undergoing validation. Two in vitro test systems, MCF-7 cells proliferation (E-screen assay) and competitive binding to estrogen receptors (ER) were selected to evaluate the estrogenic effects. 17$\beta$-Estradiol (E2) and diethylstilbestrol (DES) were used as a positive control in vitro test. Also, E2 and ethinyl estradiol (EE) were used as a positive control in vivo uterotrophic assay. In in vitro test, E2 and DES showed a strong estrogenic response at concentration of 1.0 nM. In uterotrophic assay, E2 (0.3 $\mu\textrm{g}$/kg) and EE (0.3 $\mu\textrm{g}$/kg) produced a significant increase in uterus and vagina weight in both immature and ovariectomized rats. Although we did not com-pared the specificity between in vivo and in vitro assays, these assay systems may serve as a good tool for endocrine disruptors screening methods. Our data indicate that these assay systems exhibit some difference in their sensitivity to the same estrogenic compounds. Therefore, as a first rapid screening assay for estrogenic activity qf unknown chemicals, at least two assay systems should probably be carried out with a view of high sensitivity and standardization conditions. Also, a careful validation tests are necessary to obtain a reasonable degree of reproducibility.

• Fisheries and Aquatic Sciences
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• v.19 no.1
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• pp.3.1-3.6
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• 2016

Phlorotannins are reported to have diverse biological properties. However, no analytical methods for the standardization of phlorotannin preparations have been reported. Herein, we developed and validated an analytical method for the determination of dieckol in phlorotannin extracts (PRT) using high-performance liquid chromatography (HPLC). The optimum HPLC conditions consisted of a Supelco Discovery C18 column stationary phase, a mobile phase (A: 15 % HPLC grade methanol in deionized water, B: methanol), UV detection at 230 nm, and a flow rate of 0.7 mL/min. The optimized chromatographic conditions were validated and exhibited good specificity and linearity ($R^2$ > 0.9994-1.0000). The recoveries were in the range of 100.9-102.3 %. The method had good intermediate (%RSD 1.2) and intra-day (%RSD 0.4-1.7) assay precisions. This HPLC method had good accuracy and quality in the determination of dieckol in PRT.

• Journal of Microbiology and Biotechnology
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• v.11 no.1
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• pp.21-28
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• 2001

Enzyme linked-immunosorbent assay (ELISA) for a rapid detection of fungi, Aspergillus and Penicillium genera in food, were developed and their efficiencies were approved by detecting artificially contaminated agricultural commodities. Mice were immunized with partially purified Aspergillus flavus extracellualr polysaccharide (EPS) and lymph node cells of the mice were fused with the myeloma cells for production of monoclonal antibodies. Mab 1G11, one of the antibodies, was selected and purified. A sandwich ELISA was established and its detection limit toward A. flavus EPS was 1mg/ml. Among the 59 strains tested (including 18 species of Aspergillus, 16 of Penicillium, 11 of Fusarium, 1 of Absidia, 2 of Alternaria, 2 of Candida, 2 of Cladosporium, 2 of Geotrichum, 2 of Mucor, 2 of Rhizopus, 1 of Trichoderma), species of Aspergillus and penicillium had a high reactivity with Mab 1G11 even up to 10,000 times dilution of culture broths. The other genera except Cladosporium resinae showed no reactivity, thus Mab 1G11 was specific to the genera of Aspergillus and Penicillium. The epitope of A. flavus EPS against monoclonal Mab 1G11 was on the carbohydrate moiety when 1 to 100$\mu g/g$ A. flavus EPS were put into rice, potato, and mandarin orange, the average recoveries detected by sandwich ELIA were 123, 59, and 76%, respectively. Correlation was found to be linear between the EPS, and mycelium of A. flavus and Penicillium citrinum grown in a liquid medium (r=0.87 and 0.96), and also between the EPS and colony forming unit in solid media of rice of potato (r=0.91-0.99).