• Bulletin of the Korean Chemical Society
• /
• v.27 no.9
• /
• pp.1315-1322
• /
• 2006

The following study describes the gas chromatography-mass spectrometry (GC-MS) based screening and confirmation analysis of urinary androgenic steroids. Four commercially available solid-phase extraction (SPE) cartridges, Serdolit PAD-1, Sep-pak $C_{18}$, amino-propyl, and Oasis HLB, and three different extractive organic solvents, diethyl ether, methyl tert-butyl ether (MTBE), and n-pentane, were tested for sample preparation. Overall, Oasis HLB combined with MTBE extraction provided the highest recoveries in 39 of 46 total androgenic steroids examined and it showed a good extraction yield (>82.1%) for polar steroids, such as metabolites of fluoxymesterone, oxandrolone, and stanozolol, which gave a poor recovery in both n-pentane (9.2-64.3%) and diethyl ether (22.2-73.6%) extractions. All SPE sorbents tested showed potential, because they were efficient in extraction for most or selective steroids. When applied to positive urine samples based on the results obtained, the present method allowed selective and sensitive analysis for detection of urinary androgenic steroids. The experiments showed that the high-resolution MS method is clearly more efficient than the low-resolution MS technique for the detection of many urinary steroids. However, comprehensive sample clean-up procedures also might be needed especially in confirmation analysis to increase detectability.

• Korean Journal of Environmental Agriculture
• /
• v.33 no.3
• /
• pp.194-197
• /
• 2014

BACKGROUND: Herbal extracts have been screened for their inhibitory effect of seed germination and root development on weeds, but there is a scarcity of reports for crop growth regulation. The objective of this research was to develop a growth inhibitor on Brassica campestris, and its effective extraction method from herbal medicine extract. METHODS AND RESULTS: Eighty four herbal medicine extracts were tested for their plant growth inhibition activity on B. campestris. The alcohol extracts of Artemisia annua, Cinnamomum cassia, and Mentha arvensis inhibited over 30% of germination and the extract of A. annua, and C. cassia inhibited over 70% of radicle growth at 0.1 % w/w treatment. The partially purified extracts of A. annua, and C. cassia with dichloromethane and hexane showed stronger radicle growth inhibition than the crude extracts on B. campestris. The diethyl ether extract of A. annua showed a similar 50% radicle growth inhibition ($RI_{50}$ = 45 mg/L) to its partially purified extract with dichloromethane or hexane, but the diethyl ether extract of C. cassia showed a worse $RI_{50}$ than the purified extract. CONCLUSION: The alcohol extracts of A. annua, and C. cassia showed potent radicle growth inhibition properties on B. campestris. Diethyl ether proved to be a good solvent for simple extraction from A. annua.

• Journal of Pharmaceutical Investigation
• /
• v.39 no.5
• /
• pp.321-325
• /
• 2009

5-HT$_{2C}$ receptors have been considered as therapeutic targets for the treatment of various central nervous system disorders such as depression, anxiety, epilepsy, schizophrenia and sleep disorders. We chemically synthesized KKHQ80114 (K14) and KKHQ80109 (K09), selective 5-HT$_{2C}$ agonists, with the purpose of developing therapeutic agents for the treatment of obesity. The objective of this work is to investigate analytical methods of these compounds in the plasma and urine of rats by gas chromatography/mass spectrometry. In this experiment, K14 was determined in plasma and urine by using K09 as internal standard. Calibration curves give a good linearity in plasma (r$^2$=0.9993) and urine (r$^2$=0.9988). Among hexane, ethyl acetate and diethyl ether, the highest peak was observed in diethyl ether. However, ethyl acetate was used since more interfering peaks were observed with diethyl ether. Inter-day precision and accuracy were determined in the ranges of 50-500 ng/mL for plasma and 10-500 ng/ml for urine. Quantitation limits were 50 ng/mL plasma and 25 ng/ mL urine. These data may be applicable for further studies of these compounds including absorption and metabolism due to no pharmacokinetic or analytical data available.

• Journal of Life Science
• /
• v.20 no.2
• /
• pp.253-259
• /
• 2010

The neuroprotective effects of extracts from various parts of peanut sprouts on glutamate-induced neurotoxicity in N18-RE-105 cells were investigated. This study was performed to evaluate the neuroprotective activity of methanolic extracts from the whole (WME), heads (HME), and stems (SME) of peanut sprouts. The neuroprotective effects of these extracts were measured by MTT reduction assay, LDH release assay, phase-contrast microscopy, and flow cytometric analysis on the N18-RE-105 cells. Among these extracts, the HME showed the greatest neuroprotective effects, and was further fractionated with hexane, diethyl ether, ethyl acetate, and water, according to degree of polarity. Out of the fractionated extracts, the diethyl ether layer showed the highest activity on glutamate-induced cytotoxicity in N18-RE-105 cells. The sub-G1 DNA contents of the glutamate-induced severely apoptotic N18-RE-105s were measured by flow cytometric analysis to confirm the HME's anti-apoptotic activity. Interestingly, after incubation with 100 mg/ml of the HME, the proportion of sub-G1 cells of the glutamate-stressed N18-RE-105s had been greatly reduced, from 58.5% to 9.1%. These results imply that HME may have strong potential as a chemotherapeutic agent against neuronal diseases.

• Microbiology and Biotechnology Letters
• /
• v.26 no.4
• /
• pp.331-337
• /
• 1998

The biological activities of both ethanol and water extracts from the fruiting body of E. applanata and E. applanata mycelium and the three fractions of ethanol extracts from E. applanata were compared. 91% of MCF7 cell growth was inhibited by adding 0.5 g/l of water extracts of E. applanata and 81% of MCF7 cell growth was inhibited by adding 0.5 g/l of diethyl ether and chloroform fractions. It was also showed that above 60% of Hep3B cell growth was inhibited by adding all samples including the fractions. The ethanol extracts of E. applanata mycelium showed 33.3% of cytotoxicity on normal liver cell, WRL68 in adding 0.5 g/l of the samples and 40% in adding 0.5 g/l of chloroform fractions. The result of anti-mutagenicity of all extracts and fractions including ethanol extracts of Phelinus linteus were showed that diethyl ether fractions were most effective than any other samples. Hypoglycemic activities of diethyl ether and chloroform fractions were the most effective which scores were above 75%. The enhancement of glutathione-S-transferase activity was increased above 2.3 times by adding 1.0 g/l ethanol extracts of E. applanata and diethyl ether, chloroform fractions. It can be concluded that both biological activities of the fruiting body and mycelium of E. applanata were almost equivalent.

• Analytical Science and Technology
• /
• v.22 no.6
• /
• pp.480-487
• /
• 2009

The herbicide dicamba (2-methoxy-3,6-dichlorobenzoic acid) in soil and plants was determined by gas chromatography-mass spectrometry (GC/MS). The samples were extracted with diethyl ether at pH 2, and washed with 0.1 N HCl, and then dried. The dried residue was derivatized in 1 mL of 10% $H_2SO_4$-MeOH for 2 hr at $80^{\circ}C$. The reaction mixture was neutralized with 4 mL of sodium bicarbonate solution and reextracted with 5 mL of diethyl ether. After the extract was concentrated, dicamba was determined by GC/MS-SIM mode. There was good linearity above 0.999 in the ranges of the $1.0{\sim}100{\mu}g/kg$. Total 42 sample including 32 soil samples and 10 plants samples were analyzed by developed method. Dicamba was detected in the concentration range of $2.9-123.9{\mu}g/kg$ in 15 samples among 32 soil samples and in the concentration range of $43-33,252{\mu}g/kg$ in 5 samples among 10 plants samples. A cause of the wither and die of the pine trees is suspected to spray dicamba around or directly to them.

• Proceedings of the Korean Fiber Society Conference
• /
• 2003.04a
• /
• pp.9-12
• /
• 2003

요오드 2분자가 양이온(I$^{+}$)과 음이온(I$_3$$^{-}$)로 해리되어 이 매 생성된 양이온에 의한 비닐 에테르류의 양이온 중합에 관한 연구는 보고된 바 있으나$^{1)}$ 요오드를 개시제로 사용한 삼차부틸 에테르의 양이온 중합에 관한 결과가 발표된 것은 별로 눈에 뜨이지 않는다. 삼차 부틸 에테르는 단량체의 활성이 크고 중합거동이 타 비닐 에테르류와 매우 다르기 때문에$^{3),4)}$ boron trifluoride diethyl etherate를 개시제로 하고, n-햅탄 이나 톨루엔과 같은 비극성용매를 사용하여 저온에서 중합을 행한 결과만이 보고되고 있다.$^{2)-5)}$ (중략)

• Korean Journal of Microbiology
• /
• v.17 no.4
• /
• pp.193-197
• /
• 1979

Attempts were made to elucidate the process of biodegradation of furfural. Zoogloea sp. isolated from soil could convert furfural into 2-furoic acid by a certain enzyme (s) and also accumulated it extracellularly. This substance was extracted with diethyl ether and identified with U.V. spectrophotometry, high pressure liquid chromatography (HPLC) and IR spectrophotometry.

• 한국생물공학회:학술대회논문집
• /
• 2002.04a
• /
• pp.253-256
• /
• 2002

For the antimicrobial activity test, Akebia quinata DECAISNE stem were extract water and fractionate it with four solvents which had a different polarity, antimicribial activity were increased in oder of petroleum ether fraction = diethyl ether fraction ${\leq}$ n-buthanol fraction < ethyl acetate fraction < aqueous fraction. Water extracts of stems and fruits were showed inhibitory two species bacteria](Bacillus subtills KCTC 1021, Bacillus cereus KCTC 1012) from developing.

• Korean Journal of Food Science and Technology
• /
• v.32 no.5
• /
• pp.1029-1034
• /
• 2000

A suitable method of sample treatments to minimize the analytical interferences was presented in order to determine bisphenols [bisphenol F (BPF), bisphenol A (BPA), bisphenol F diglycidyl ether (BFDGE), and bisphenol A diglycidyl ether (BADGE)] in various canned beverages coated with epoxy resin by the reversephase high performance liquid chromatography (RP-HPLC) equipped with a fluorescence detector and the gas chromatography with mass selective detection. The recovery test of bisphenols was performed using 1, 5, and 10 ${\mu}g/L$ bisphenols spiked beverages with the combined technique of the solid-phase extraction (SPE) and the liquid-phase extraction (LPE). Both BPA and BADGE showed quite adequate resolutions in HPLC-chromatograms. The recoveries of BPA obtained by LPE with diethyl ether were higher than those obtaind with methylene chloride on coffee, shikhye and fruit juice. For cola and tea, the recoveries of BPA obtaind by SPE were higher than those by LPE with diethyl ether. The recoveries of BADGE were less than those of BPA for all beverage samples treated by either SPE or LPE method. In survey of bisphenols for eighteen commercial canned beverage samples, BPA contents of coffee, cola, tea, shikhye, and fruit juice were in the range of $1.3{\sim}11.6,\;0.5{\sim}0.9,\;1.0{\sim}1.3,\;2.4{\sim}7.9$, and $3.0{\sim}3.4\;{\mu}g/L$, respectively, but there was no detection of BPA in beer sample.