• 한국식품과학회지
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• 제51권4호
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• pp.316-323
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• 2019

이 연구에서는 레몬이나 오렌지와 같은 감귤류 과일에서 잔류 농약인 피메트로진을 분석함에 있어 기존 분석법의 한계점을 파악하고 효율적인 분석을 위해 이를 개선하고자 하였다. 감귤류 과일의 경우 산성을 띄고 있어 기존의 하이드로매트릭스법을 이용하여 피메트로진을 분석 시 효율적인 정제 능력이 부족하여 피메트로진의 머무름 시간에 많은 매트릭스 peak가 나타나 검출에 어려움이 발견되었다(Fig. 2). 이에 액-액 분배법을 이용하여 감귤류 과일의 피메트로진을 분석하였으나 액-액 분배 단계에서 추출 용매로 이용되는 DCM은 발암 가능성 물질로 알려져 있어, DCM의 사용량을 낮추면서 분배 효율에 영향을 미치지 않는 용량(첫번째 분배 시 80 mL과 두번째 분배 시 70 mL 첨가)을 설정하였다(Table 2). 또한 액-액 분배법에 따라 감귤류 과일을 추출할 경우 pH가 6.0 이하로 나타났으며, 이는 피메트로진의 추출 효율에 영향을 미치게 되므로 붕사 완충 용액과 1 N NaOH를 레몬과 라임의 경우에는 각각 25와 5 mL, 오렌지, 감귤 및 자몽의 경우에는 각각 15와 1 mL을 첨가하여 감귤류 과일 추출물의 pH를 7.0 이상으로 유지하였다(Table 3). 최종적으로 개선된 액-액 분배법(Fig. 1B)에 따라 5 종류의 감귤류 과일인 레몬, 라임, 오렌지, 감귤, 그리고 자몽을 추출 및 정제 후 HPLC-PDA를 이용하여 분석하였다. 분석법의 유효성 검증 결과, 검량선을 통해 얻은 직선성($r^2$)은 0.9999로 나타났고, LOD와 LOQ는 각각 4.360과 $14.533{\mu}g/kg$이었다. MQL은 0.007 mg/kg으로 현재 공전 상 피메트로진에 대하여 설정된 MRLs인 0.03-3.0 mg/kg의 1/2 이하까지 검출 가능하였다(Table 4). 또한 레몬, 라임, 오렌지, 감귤 및 자몽에 각각 피메트로진을 첨가하여 최종적으로 분석 값이 0.3 mg/kg이 되도록 실험한 결과, 각각의 평균 회수율은 71.8, 72.0, 79.9, 79.7, 및 83.7%이었고, CV는 각각 2.4, 2.0, 4.9, 1.1, 및 5.9%로 나타나 잔류 농약 분석 기준인 70-120%의 회수율과 10% 이내의 CV값을 만족하였다(Table 4). 따라서 본 연구를 통해 개선된 분석법은 산성을 띄는 감귤류 과일에서 피메트로진의 분석법으로 사용 가능함을 확인하였으며, 또한 향후 수입되는 산성도가 높은 과일의 피메트로진 분석 시에도 적용 가능할 것으로 기대된다.

• 분석과학
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• 제36권6호
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• pp.291-299
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• 2023

식용유지 중 benzo[a]pyrene 추출법으로 액체-액체 추출법, Soxhlet 추출법, 초음파 추출법 등이 사용되고 있으나 이런 방법들은 추출 시간이 길고 많은 양의 용매를 사용하는 단점이 있다. 따라서 본 연구에서는 간편하고 단시간에 분석이 가능한 QuEChERS법을 적용하여 현재의 복잡한 benzo[a]pyrene 분석법을 개선하고자 하였다. 본 연구에서 적용한 QuEChERS법은 식용유지를 n-hexane saturated acetonitrile과 n-hexane으로 녹인 후 magnesium sulfate, sodium chloride를 이용해 추출하는 방식이다. 이 시험법에 대한 유효성 검증 결과, 검출한계와 정량한계는 각각 0.02, 0.05 ㎍/kg 이며, 직선성은 0.1~10 ㎍/kg 농도 범위에서 검량선 결정계수 (R²)는 0.99 이상이었다. 회수율과 회수율에 대한 상대표준편차는 각각 74.5~79.3 %, 0.52~1.58 % 였으며, 정확성 및 정밀성은 각각 72.6~79.4 %, 0.14~7.20%로 나타났다. 위의 결과들은 식품의약품안전평가원의 「식품 등 시험법 마련 표준절차에 관한 가이드라인 (2016)」 및 「시험법 마련 표준절차 AOAC 가이드라인 (2023)」을 모두 만족하였다. 따라서 본 연구에서 제시된 분석법은 기존 분석법 대비 상대적으로 간편한 전처리 방법으로 분석 시간과 용매 사용량을 각각 92 %, 96 % 정도 절감할 수 있었다.

• Archives of Pharmacal Research
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• 제11권3호
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• pp.203-212
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• 1988

To find antitumor components from the higher fungi of Korea, the mycelia of Favolus alveolarius (Fr.) Quelet were cultured in a liquid medium. The cultured mycelia were extracted with hot water twice, and a high molecular weight fraction was obtained by adding two volumes of ethanol to the extract. Two grams of Fraction A were obtained by dialyzing it. It was further separated into four fractions by gel filtration with Sepharose CL-4B, and they were designated Fractions B, C, D, and E. The results of the antitumor test showed that Fractions A, B, C, D and E had tumor inhibition ratios of 92.3, 78.5, 59.6, 77.4 and 62.2%, respectively. Anthrone test was carried out to determine the contents of total polysaccharide of the five fractions, and they had 46.3, 27.3, 65.3, 64.6, and 46.1%, respectively. The contents of the total protein of the five fractions were 29.4, 13.9, 14.3, 14.3, and 29.1%, respectively. Monosaccharide subunits of each fraction were analyzed with gas chromatography, and glucose, xylose, mannose, galactose and fucose were identified. Fraction A was examined for immunological effects. It increased the count of hemolytic plaque forming cells 12.8 times to that of the control group, and the population of macrophage in peritoneal cavity 3.2 times to that of the control group.

• KSBB Journal
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• 제23권4호
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• pp.297-302
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• 2008

오죽으로부터 HPLC On-line $ABTS^{+}$ screening기법을 사용하여 Flavone C-glycosides의 특성중의 하나인 항산화활성을 빠르게 분석하였으며, 오죽으로부터 homoorientin와 orientin의 추출을 다양한 초음파 주파수와 시간의 추출방법을 적용하였다. 전처리한 추출액에 포함된 오죽의 Flavone C-glycosides을 분석하고 최적의 추출조건을 실험적으로 모색하였다. 실험결과에 의하면 전체 수율에서는 Frequency 72 KHz, 60분에서 3.37 mg으로 추출 효율이 높았고, homoorientin와 orientin의 항산화활성은 Frequency 35 KHz, 30분으로 추출한 시료가 73.8%와 14.8%로 가장 우수하였다.

• 한국수산과학회지
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• 제33권1호
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• pp.32-37
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• 2000

본 연구는 갈색 해조류로부터 추출한 alginate를 사용하여 제조한 Ag-alginate에 대한 최적의 은 첨가량을 구하여 항균성능을 측정하고, 기존의 상품으로 판매되고 있는 항균제의 성능과 비교하였다. 포도상구균과 대장균의 성장은 pH 7에서 가장 활발하였으며, 포도상구균은 pH에 매우 민감하였으나, 대장균은 pH 변화에 대한 저항력을 어느 정도 나타내었다. 포도상구균은 배양 초기에 일정기간의 사장시간 (dead time)이 경과한 후 급격하게 성장하였고, 대장균은 약 20분 이내의 사장시간이 경과한 후 완만하게 성장하였다. 해조류로부터 추출한 alginate를 정제하여 제조한 Ag-alginate의 경우, 포도상구균 및 대장균에 대해서 $0.006\;wt.{\%}$ 은을 첨가한 배양액에서 우수한 항균성능을 나타내었으며, 포도상구균보다 대장균에 대하여 더 강한 항균력을 나타내었다. 그러나 미역 및 다시마로부터 추출한 alginate를 정제하지 않고 제조된 Ag-alginate의 경우, 포도상구균 및 대장균에 대한 항균성능은 현저하게 감소되었다. 국내에서 수입되어 항균섬유용으로 많이 사용되고 있는 Agzeolite계 제품의 항균력과 비교하여도 유사한 항균성능을 나타내고 있으므로 Ag-alginate는 수술용 봉합사, band, gauze, 붕대 등과 같은 의료용 섬유에 사용이 가능하다고 판단된다.

• 대한한의학회지
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• 제25권4호
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• pp.1-7
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• 2004

Objective : This study was designed to examine the effects of orally administered Prunus persica water extract (PPE), which is used as herbal medicine, for treatment of Yu Xue (stasis of blood) and tacrine on the basal concentration of extracellular acetylcholine in the hippocampus of rats. Methods: To investigate the effects of PPE and tacrine on concentration of extracellular acetylcholine in the hippocampus of rats, the microdialysis technique, under the same experimental conditions, was used. And we used male Wistar rats which were 7 weeks of age and 210-290 g. PPE was extracted with boiling water, and the rats were anesthetized with pentobarbital Na. Their skulls were exposed and a hole was drilled for implantation of a microdialysis probe. In order to increase the recovery of acetylcholine, a probe with a long membrane was used. One day after surgery, the microdialysis probe was perfused with Ringer's solution at a flow rate of 1.5 l/min. The acetylcholine concentration in dialysis samples was measured by high-performance liquid chromatography (HPLC) with electrochemical detection. AChE activity was measured using the radiometric method, as described by Sherman. Results : The comparative effects of PPE and tacrine on hippocampal extracellular acetylcholine concentration was that these cholinesterase inhibitors produced dose-dependent increases in the extracellular acetylcholine concentration. And the effect of PPE and tacrine on rat brain AChE activity was that PPE produced maximal inhibition at 1 h after administration, when AChE activity was 44% of the intact level. AChE activity gradually recovered thereafter, and reached 78% of the intact level at 12 h after administration. Conclusion : In this study, PPE has a potent activity and a long-lasting effect on the central cholinergic system, in terms of the basal concentration of extracellular acetylcholine in the hippocampus and the AChE activity in the brain of rats. And oral administration of PPE increased dose-dependently the basal concentration of extracellular acetylcholine in the hippocampus of rats. PPE may be one of the more useful cholinesterase inhibitors for the treatment of Alzheimer's disease.

• 약학회지
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• 제57권5호
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• pp.330-336
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• 2013

"The Act on Medication Treatment of Sexual Impulse of Sex Offenders" known as chemical castration has been effective since July 2011 in Korea. According to the law, monitoring of male sex hormone in urine is enforced to request National Forensic Service more than once a month after injection of medicine designed to reduce sex impulse. We established a rapid and sensitive method for the monitoring of testosterone (T) and epitestosterone (E) in human urine by liquid chromatography with tandem mass spectrometry (LC-MS/MS). Three mL of urine was pretreated by solid-phase extraction for purification and performed enzymatic hydrolysis. The pretreated samples were extracted twice with 2 ml of ethyl acetate and n-hexane (2 : 3). The separation was applied on Thermo Hypersil GOLD C18 column ($1.9{\mu}m$, $100{\times}2.1mm$). A gradient elution of methanol and water of 0.1% formic acid were used as mobile phase and the retention time was less than 10 min. LC-MS/MS system coupled with an electrospray ionization source was performed in multiple reaction monitoring mode. The transitions of the analytes executed as following: m/z $289{\rightarrow}97$, 109 for T and E, m/z $292{\rightarrow}109$ for $T-d_3$ and $E-d_3$ as internal standards. The validation results of the method were satisfactory. The limits of detection were 0.05 ng/ml and the limits of quantification were 0.1 ng/ml. This method was successfully applied to real human urine sample. The developed method will be useful for monitoring T/E ratio in urine of sex offenders.

• 한국환경농학회지
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• 제34권2호
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• pp.111-119
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• 2015

BACKGROUND: Ethychlozate (ECZ) is a plant growth regulator of synthetic auxin for agricultural commodities (ACs). Accurate and sensitive method to determine ECZ in diverse ACs on global official purpose is required to legal residue regulation. As the current official method is confined to the limited type of crops with poor validation, this study was conducted to improve and extend the ECZ method using high-performance liquid chromatography (HPLC) in all the registered crops with method verification. METHODS AND RESULTS: ECZ and its acidic metabolite (ECZA) were both extracted from acidified samples with acetone and briefly purified by dichloromethane partition. ECZ was hydrolyzed to form ECZA and the combined ECZA was finally purified by ion-associated partition including hexane-washing. The instrumental quantitation was performed using HPLC/ FLD under ion-suppression of ECZA with no interference by sample co-extractives. The average recoveries of intra- and inter-day experiment ranged from 82.0 to 105.2% and 81.7 to 102.8%, respectively. The repeatability and reproducibility for intra- and inter-day measurements expressed as a relative standard deviation was less than 8.7% and 7.4%, respectively. CONCLUSION: Established analytical method for ECZ residue in ACs was applicable to the nation-wide pesticide residues monitoring program with the acceptable level of sensitivity, repeatability and reproducibility.

• 한국발생생물학회지:발생과생식
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• 제17권4호
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• pp.421-426
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• 2013

In this study, oocyte steroidogenesis are investigated in relation to oocyte development in the starry flounder, Platichthys stellatus, a marine multiple spawner. Vitellogenic (0.52 and 0.55 mm oocyte diameter) and mature oocytes (0.63, 0.66 and 0.71 mm oocyte diameter) were incubated in vitro in the presence of $[^3H]17{\alpha}$-hydroxyprogesterone ($[^3H]17{\alpha}$-OHP) as a precursor. Steroid metabolites were extracted from the incubated media and oocytes, the extracts were separated and identified by thin-layer chromatography (TLC), high performance liquid chromatography (HPLC) and gas chromatographymass spectrometry (GC-MS). The major metabolites produced from $[^3H]17{\alpha}$-OHP were androgens [androstenedione ($A_4$) and testosterone (T)] and estrogens [$17{\beta}$-estradiol ($E_2$) and estrone ($E_1$)] and progestins [$17{\alpha},20{\alpha}$-dihydroxy-4-pregnen-3-one ($17{\alpha}20{\alpha}P$) and $17{\alpha},20{\beta}$-dihydroxy-4-pregnen-3-one ($17{\alpha}20{\beta}P$)] in vitellogenic and mature oocytes. The results from this study suggest the potential roles of $E_1$ in the oocytes with diameter 0.52-0.71 mm, $17{\alpha}20{\alpha}P$ and $17{\alpha}20{\beta}P$ at the oocytes of 0.63, 0.66 and 0.71 mm.

• Journal of Plant Biotechnology
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• 제44권2호
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• pp.191-202
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• 2017

Chemical compounds from four different tissues of the kenaf plant (Hibiscus cannabinus), a valuable medicinal crop originating from Africa, were examined to determine its potential for use as a new drug material. Leaves, bark, flowers, and seeds were harvested to identify phytochemical compounds and measure antioxidant activities. Gas chromatography mass spectrometry analyses identified 22 different phytocompounds in hexane extracts of the different parts of the kenaf plant. The most abundant volatile compounds were E-phytol (32.4%), linolenic acid (47.3%), trisiloxane-1,1,1,5,5,5-hexamethyl-3,3-bis[(trimethylsilyl)oxy] (16.4%), and linoleic acid (46.4%) in leaves, bark, flowers, and seeds, respectively. Ultra-high performance liquid chromatography identified the major compounds in the different parts of the kenaf plant as kaemperitrin, caffeic acid, myricetin glycoside, and p-hydroxybenzoic acid in leaves, bark, flowers, and seeds, respectively. Water extracts of flowers, leaves, and seeds exhibited the greatest DPPH radical scavenging activity and SOD activity. Our analyses suggest that water is the optimal solvent, as it extracted the greatest quantity of functional compounds with the highest levels of antioxidant activity. These results provide valuable information for the development of environmentally friendly natural products for the pharmaceutical industry.