• Korean Journal of Environmental Agriculture
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• v.37 no.2
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• pp.104-116
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• 2018

BACKGROUND: This experiment was conducted to establish a simultaneous analysis method for 7 kinds of herbicides in 3 different classes having similar physicochemical property as diphenyl ether(bifenox and oxyfluorfen), dinitroaniline (ethalfluralin and trifluralin), and chloroacetamide (metolachlor, pretilachlor, and thenylchlor) in crops using GC-ECD/MS. METHODS AND RESULTS: All the 7 pesticide residues were extracted with acetone from representative samples of five raw products which comprised apple, green pepper, Kimchi cabbage, hulled rice and soybean. The extract was diluted with saline water and directly partitioned into n-hexane/dichloromethane(80/20, v/v) to remove polar co-extractives in the aqueous phase. For the hulled rice and soybean samples, n-hexane/acetonitrile partition was additionally employed to remove non-polar lipids. The extract was finally purified by optimized Florisil column chromatography. The analytes were separated and quantitated by GLC with ECD using a DB-1 capillary column. Accuracy and precision of the proposed method was validated by the recovery experiment on every crop samples fortified with bifenox, ethalfluralin, metolachlor, oxyfluorfen, pretilachlor, thenylchlor, and trifluralin at 3 concentration levels per crop in each triplication. CONCLUSION: Mean recoveries of the 7 pesticide residues ranged from 75.7 to 114.8% in five representative agricultural commodities. The coefficients of variation were all less than 10%, irrespective of sample types and fortification levels. Limit of quantitation (LOQ) of the analytes were 0.004 (etahlfluralin and trifluralin), 0.008 (metolachlor and pretilachlor), 0.006 (thenylchlor), 0.002 (oxyfluorfen), and 0.02 (bifenox) mg/kg as verified by the recovery experiment. A confirmatory technique using GC/MS with selected-ion monitoring was also provided to clearly identify the suspected residues. Therefore, this analytical method was reproducible and sensitive enough to determine the residues of bifenox, ethalfluralin, metolachlor, oxyfluorfen, pretilachlor, thenylchlor, and trifluralin in agricultural commodities.

• The Korean Journal of Pesticide Science
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• v.15 no.3
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• pp.254-268
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• 2011

Fenoxycarb, pyriproxyfen and methoprene are juvenile hormone mimic insecticide. These insecticides have been widely used for mosquito, fly, scale insects, and Lepidoptera. The purpose of this study was to develop a simultaneous determination procedure of fenoxycarb, pyriproxyfen and methoprene residues in crops using HPLC-UVD/MS. These insecticide residues were extracted with acetone from representative samples of four raw products which comprised brown rice, apple, green pepper, and Chinese cabbage. The extract was diluted with saline water, and then n-hexane/dichloromethane partition was followed to recover these insecticides from the aqueous phase. Florisil column chromatography was additionally employed for final clean up of the extract. The analytes were quantitated by HPLC-UVD/MS, using a $C_{18}$ column. The crops were fortified with each insecticide at 3 levels per crop. Mean recovery ratios were ranged from 80.0 to 104.3% in four representative agricultural commodities. The coefficients of variation were less than 4.8%. Quantitative limit of fenoxycarb, pyriproxyfen, and methoprene was 0.04 mg/kg in crop samples. A HPLC-UVD/MS with selected-ion monitoring was also provided to confirm the suspected residues. The proposed simultaneous analysis method was reproducible and sensitive enough to determine the residues of fenoxycarb, pyriproxyfen and methoprene in the agricultural commodities.

• Korean Journal of Environmental Agriculture
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• v.40 no.4
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• pp.353-358
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• 2021

BACKGROUND: Prochloraz has been widely used as an imidazole fungicide on fruits and vegetables in Korea. Analytical approaches to evaluate prochloraz residues in herbal medicine are required for their safety management. In this study, we developed a GC-ECD method for quantitative determination of prochloraz in Platycodi Radix. The metabolite 2,4,6-trichlorophenol (2,4,6-T) was used as a target compound to evaluate total prochloraz residues as it is categorized to a representative residue definition of prochloraz. All residues containing 2,4,6-T were converted to 2,4,6-T and subjected to GC-ECD. METHODS AND RESULTS: In order to verify the applicability, the method was optimized for determining prochloraz and it metabolite 2,4,6-T in Platycodi Radix. Prochloraz and its metabolite 2,4,6-T residuals were extracted using acetone. The extract was diluted with and partitioned directly into dichloromethane to remove polar co-extractives in the aqueous phase. The extract was decomposed to 2,4,6-T, and then the partitioned ion-associate was finally purified by optimized aminopropyl solid-phase extraction (SPE). The limits of quantitation of the method (MLOQs) were 0.04 mg/kg and 0.02 mg/kg, respectively for prochloraz and 2,4,6-T, considering the maximum residue level (MRL) of prochloraz as 0.05 mg/kg in Platycodi Radix. Recovery tests were carried out at two levels of concentration (MLOQ, 10 MLOQ) and resulted in good recoveries (82.1-89.7%). Good reproducibilities were obtained (coefficient of variation < 2.8%), and the linearities of calibration curves were reasonable (r² > 0.9986) in the range of 0.005-0.5 ㎍/mL. CONCLUSION(S): The method developed in this study was successfully validated to meet the guidelines required for quantitative determination of pesticides in herbal medicine. Thus, the method could be useful to monitor prochloraz institutionally in herbal medicine.

• The Journal of Korean Medicine Ophthalmology and Otolaryngology and Dermatology
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• v.18 no.2
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• pp.10-27
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• 2005

Objectives: To study the effectiveness of Sanpunggosamhwan(SGH) against Allergic Contact Dermatitis(ACD), the contact hypersensitivity assay, change of cutaneous shape, anti-allergic effect, anti-inflammatory effect, and the effect on skin barrier were observed. Methods: The 200g rats were divided into three groups of 15 rats. The first group is the Normal group which was applied Acetone olive oil only. The second group is the ACD group which has intentionally activated Allergic Contact Dermatitis by DNCB. The third group is the SGH group which was given medication of Sanpunggosamhwan extract after the induction of Allergic Contact Dermatitis by DNCB. Each group of rats was observed after 24, 48 and 72 hours. Results: I. With the result of contact hypersensitivity assay, at 24hours SGH group showed appreciably less ear swelling than ACD group. 2. Regarding general change of skin, SGH group showed less hyperplasia of epidermis, less damage of epidermis than ACD group. 3. Regarding the number of WBC, ACD group showed significantly less than normal and SGH group at 72 hours. 4. Regarding the number of RBC in blood, ACD and SGH group showed significantly more RBC than normal group at 24, 48, 72 hours. 5. Regarding the ratio of neutrophil in WBC, ACD and SGH group showed significantly high percentage than normal group at 24, 48 hours. 6. Regarding the ratio of lymphocyte in WBC, ACD and SGH group showed significantly high percentage than normal group at 48 hours. 7. Regarding the erythema, SGH group showed significantly more erythema than normal and ACD group at 48 hours. 8. Regarding the melanin, SGH group showed significantly less melanin than normal group at 24 hours.9. Regarding the skin hydration, SGH group showed significantly high value than and ACD group at 72 hours. 10. Regarding the skin pH, ACD group showed significantly high value than normal and SGH group af 24 hours. 11. Regarding the number of Total IgE, ACD and SGH group showed more Total IgE than normal. g개up at 24 hours. 12. At Electro microscope-morphologic changes of skin, the damage of epithelium was decreased and regeneration power of skin was increased in the SGH group. Conclusions: The Sanpunggosamhwan extract administration was effective on the mitigation of skin damage in rats with allergic contact dermatitis.

• Journal of Life Science
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• v.21 no.5
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• pp.734-738
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• 2011

Aging in humans is inexorable and inescapable. The progressive decrease of physiological capacity and the reduction of the ability to cope with environmental stresses lead to increased susceptibility and vulnerability to human disease. Recently, in the cosmetic industry, many researchers have paid considerable attention to delaying or improving the symptoms of skin aging. Since the early 1990`s, there have been various challenges in developing cosmeceutical products which have strong anti-aging effects, and this has been an important issue in the cosmetic industry. Meanwhile, development of anti-aging cosmetics supported by biochemical activities in the skin has been researched. Castanea crenata inner Shell solvent extracts were investigated for anti-wrinkle and whitening effects, in order to apply it as a functional ingredient for cosmetic products. For anti-wrinkle effect, elastase inhibition activity of Castanea crenata inner shell acetone extract (CA) was 51.0% at a concentration of 100 ug/ml. The collagenase inhibition activity of CA and Castanea crenata inner shell ethanol extract (CE) was 96.4%, 94.3% at a concentration of 50 ug/ml. The tyrosinase inhibitory effect, which is related to skin-whitening, was 47.2% and 45.8% in CA and CE at a concentration of 500 ug/ml. All these results suggest that Castanea crenata inner shell can be effectively used as a cosmeceutical ingredient for the prevention of wrinkles.

• Journal of the Korean Society of Food Science and Nutrition
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• v.36 no.3
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• pp.269-275
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• 2007

In this experiment, the effects of Asterina pectinifera extracts on the activation of immune cells were studied. An immune cell activating factor was partially purified from starfish, Asterina pectinifera, by means of physiological saline extraction, acetone precipitation and heating inactivation. Starfish extracts increased the proliferation of spleen cells and induced the production of IL-6 and $IFN-{\gamma}$ by spleen cells. Also, it increased the proliferation of purified B cells and production of IgM and IgG in the presence of Asterina pectinifera extracts. Starfish extract self-induced NO synthesis in mouse macrophage cell line (RAW264.7). When cell lines was treated with extracts, the mRNA expression of inducible NO synthetase (iNOS), $TNF-{\alpha}$, IL-6, and GM-CSF were markedly increased in RT-PCR analysis. Therefore starfish extract can self-activate spleen cells, B cells and macrophages. These results might be useful in further studies into a possible immune activating agent from the starfish, Asterina pectinifera, for the development of functional foods and drugs.

• Journal of Life Science
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• v.25 no.11
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• pp.1298-1303
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• 2015

Machilus thunbergii (Lauraceae) is an evergreen tree cultivated in Korea and Japan. M. thunbergii has long been used as a traditional medicine in Korea, China, and Japan to treat various diseases, including edema, abdominal pain, and abdominal distension. In this study, dried stem bark of M. thunbergii extracted in methanol and extract was partitioned into n-hexane, CHCl₃, and BuOH. The CHCl₃-soluble extracts chromatographed on silica gel column using a CHCl₃/acetone and n-hexane/EtOAc mixture to afford Compound 1 and 2. Two dibenzylbutane lignans, macelignan (1) and meso-dihydroguaiaretic acid (2), were isolated from the CHCl₃-soluble extract of M. thunbergii stem bark. The structures of 1 and 2 were determined by ¹H- and ¹³C-NMR spectroscopic data analyses and a comparison with literature data. The tyrosinase inhibitory activity of the isolated compounds was evaluated. Among these compounds, Compound 2 strongly inhibited the monophenolase (IC₅₀=10.2 μM) activity of tyrosinase. A kinetic analysis showed that Compound 2 was a competitive inhibitor. The apparent inhibition constant (K_i) for Compound 2 binding to free enzyme was 4.8 μM. Based on these results, it can be concluded that meso-dihydroguaiaretic acid (2) is a potential candidate for the treatment of melanin biosynthesis-related skin diseases.

• Korean Journal of Food Science and Technology
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• v.38 no.3
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• pp.419-426
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• 2006

A thermophilic microorganism, strain JE 375, which produces a thermostable protease, was isolated from soil and compost in Korea. This gram-positive, rod-shaped, catalase positive, motility positive, and hemolysis ${\beta}$ containing organism was implicated in glucose fermentation, mannitol fermentation, xylose oxidation, aerobic activity and spore formation. The color of the colony was yellowish white. The temperature range for growth at pH 6.5 was between 55 and $70^{\circ}C$, with an optimum growth temperature of $65^{\circ}C$. This result confirmed the strain JE 375 as a thermophilic microorganism. The enzyme was produced aerobically at $65^{\circ}C$ during 20 hr in a medium (pH 6.5) containing 1% trypton. 1% maltose, 0.5% yeast extract and 1% NaCl. The 16S rDNA of strain JE 375 had 97.6% sequence similarity with the 16S rDNA of Bacillus caldoxyloyticus. On the basis of biochemical and physiological properties and phylogenetic analysis, we named the isolated strain as Bacillus sp. JE 375. The thermostable protease from Bacillus sp. JE 375 had been partially purified and characterized. The molecular weight of the enzyme was deduced from SDS-PAGE and gel chromatography as 55 kDa and its optimal temperature was $60^{\circ}C$. The enzyme showed its highest activity at pH 7.5 and was stable from pH 7.0 to 8.0.

• Korean Journal of Food Science and Technology
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• v.45 no.3
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• pp.385-390
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• 2013

The effect of tuna extracts on the production of nitric oxide (NO) and cytokines including interleukin-6 (IL-6), tumor necrosis factor-${\alpha}$ (TNF-${\alpha}$), and interferon-${\gamma}$ (IFN-${\gamma}$), was investigated. All extracts and fractions from tuna significantly reduced NO production induced by lipopolysaccharide (LPS). The acetone+methylene chloride (A+M) extract, n-hexane and 85% aqueous methanol (MeOH) fractions had stronger inhibitory effects among them. The 85% aqueous MeOH fraction at a 10-${\mu}g$ concentration significantly decreased LPS-induced IL-6 and TNF-${\alpha}$ productions at 6 h of incubation. In the case of LPS-induced IFN-${\gamma}$ production, the 85% aqueous MeOH fraction at a 3-${\mu}g$ concentration showed significantly higher levels at 48 h of incubation. These results show that the 85% aqueous MeOH fraction inhibited the production of NO and pro-inflammatory cytokines (IL-6, TNF-${\alpha}$), suggesting that this fraction acts as a potent immunomodulator.

• Journal of Life Science
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• v.22 no.8
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• pp.1107-1113
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• 2012

In this experiment, the effects of Pueraria thunbergiana extracts on the activation of immune cells were studied. An immune cell-activating factor was partially purified from P. thunbergiana by means of physiological saline extraction, acetone precipitation, and heating inactivation. P. thunbergiana extracts increased the proliferation of spleen cells and induced the production of IL-2, IL-6, TNF-${\alpha}$, and IFN-${\gamma}$ by spleen cells. Also, they increased the proliferation of purified B cells and the production of IgM antibody in a dose-dependent fashion. The extract self-induced NO synthesis in a mouse macrophage cell line (RAW264.7). When cell lines were treated with extracts, the cytokines' (IL-$1{\beta}$, IL-6, and TNF-${\alpha}$) production was markedly increased. Therefore, P. thunbergiana extract can self-activate spleen cells, B cells, and macrophages. These results might be useful in further studies into a possible immune-activating agent derived from P. thunbergiana for the development of functional foods and drugs.