• 한국식품영양과학회지
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• 제35권10호
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• pp.1405-1411
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• 2006

국내에서 유통되는 국내외 브랜드의 extra virgin급과 정제/혼합 올리브유에 잔류된 헥산의 함량을 측정하기 위하여 신속하고 간편한 headspace법을 이용한 전자코(a-FOX 3000, Alpha M.O.S., France)를 이용하여 분석하였으며, head-space-SPME 법을 사용한 GC/MS 분석방법을 이용하여 정량하였다. 전자코 분석결과, 올리브유에 함유된 헥산의 존재 유무 및 농도를 예측할 수 있을 것으로 사료되었으며, 1차로 수거된 국내에 유통 중인 5종의 국내 브랜드 extra virgin급, 10종의 국외브랜드 extra virgin급과 7종의 국내외 브랜드인 혼합/정제 올리브유의 경우 헥산의 잔류 합유량은 잔류되어 있지 않거나, 잔류되어 있다고 하더라도 국내 허용치인 5 ppm 미만으로 예측되었다. 잔류 헥산을 정량하기 위하여 polydimethylsiloxane(PDMS)으로 코팅된 fiber를 사용한 headspace SPME-GC/MS를 사용하였다. 이 때 시료의 head space산출을 위한 최적의 휘발촉진 온도를 선정하기 위하여 각 온도별 검량선 작성한 결과 $R^2$값이 99.99%로 가장 재현성이 높을 것으로 판단되는 $70^{\circ}C$에서 30 min 동안의 휘발촉진과정을 통하여 휘발성분을 fiber에 흡착하였다. 1차로 수집한 총 22개의 올리브유 중 총 6개의 시료에서 헥산이 검출되었고, 2차로 수집한 총 19개의 올리브유에서는 총 2개의 시료에서 헥산이 검출되었으나, 검출된 잔류 헥산의 양은 모두 국내 규정한계농도(5 ppm) 이하인 1 ppm 이하인 것으로 확인되었다.

• Korean Chemical Engineering Research
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• 제56권4호
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• pp.536-541
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• 2018

Excess molar volumes ($V_m^E$) of binary mixtures of 1-propanol or 2-propanol (1) + cyclohexane or n-hexane (2) were measured with V-shaped dilatometer at 303.15 K. The $V_m^E$ data for these mixtures varied as: 2-propanol > 1-propanol and were higher for cyclohexane than n-hexane for both propanol systems. The experimental data were correlated with Redlich-Kister polynomial. The $V_m^E$ data were interpreted qualitatively as well as quantitatively in terms of Flory-Treszczanowicz-Benson model and Prigogine-Flory-Patterson theory. Both models correctly described the sign and shape of $V_m^E$ vs $x_1$ curves. The values calculated by both the models agree well with the experimental data.

• Applied Biological Chemistry
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• 제36권2호
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• pp.134-137
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• 1993

우리나라 전지역의 산과 들에 야생하고 있는 고들빼기(Youngia sonchifolia Max.)는 전통식품인 고들빼기 김치의 원료로 이용될 뿐만 아니라 오래전부터 민간에서 위장장애 치료재로 이용되어 왔다. 그래서 고들빼기의 생화학적 활성 및 항암 실험과 그 특수성분을 분석하였는데 hexane 추출물 중에서 silica gel column chromatography와 재결정으로 얻어낸 화합물은 무색판상 결정으로 융점이 $280{\sim}282^{\circ}C$ 이었으며 구조결정을 위해 $^{13}C-NMR$, $^1H-NMR$, MS로 분석한 결과 pentacyclic triterpene인 bauerenyl acetate인 것을 확인하였다.

• KSBB Journal
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• 제15권1호
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• pp.55-59
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• 2000

생난황으로부터 시알산 함유 올리고당을 직접 생산하기 위한 biphasic system(water-immiscible hexane system)의 최적 조건을 조사하였다. Biphasic system I은 II보다 생산수율이 높았으며, 온도, 함수율 및 반응 시간의 최적조건은 각각 $30^{\circ}C$, 20%, 12시간이었다. Biphasic system I 에서, 난황을 가수분해하기 위한 3종류의 효소(protease A, corolase 7089, neutrase 0.5L)의 활성은 함수율과 온도에 강하게 영향을 받았으나, biphasic system II에서는 온도($30^{\circ}C$와 $50^{\circ}C$)의 영향을 거의 받지 않았다. 두 종류의 biphasic system에서 반응시간 12시간까지는 시알산 함유 올리고당의 생산량이 증가되었으나, 15시간 이후에는 거의 증가하지 않았다.

• 한국식품영양과학회지
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• 제28권5호
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• pp.973-979
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• 1999

Volatile compounds from twigs, needles and sprouts in Pinus densiflora were extracted with n hexane, diethyl ether or ethanol for 24 hours, and the extracted compounds were separated and identified by gas chromatography and mass selective detector. The kinds and amount of volatile compounds extracted from three parts of Pinus densiflora were different in solvent extraction and the extraction by the modified Liken Nickerson apparatus. The contents of volatile compounds of twigs contained more than those of needles and sprouts, and the volatile compounds were extracted more in n hexane than the others. In the extraction with hexane, the main volatile compounds of twigs were 18.5% pinene, 14.5% limonene, 12.7% pinene and 3.2% myrcene. Sprouts were 16.8% limonene, 4.4% pinene, 4.3% pinene and 1.7% myrcene. Needles contained 14.7% pinene, 5.4% pinene, 2.2% limonene and 0.8% myrcene. The highest yield for pine aroma was shown in the extraction from pine twigs with n hexane, and in this extraction the amounts of pinene, pinene and limonene were 742 g, 1108 g and 922 g per gram sample, respectively.

• 한국식품위생안전성학회지
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• 제12권1호
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• pp.63-70
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• 1997

The extracts from Agastache rugosa O. Kuntze, their chloroform and hexane fractions, and estragole identified from hexane fraction were tested to investigate the effects on the growth and metabolic activities of several true fungi. The fungi used were: Aspergillus oryzae KFCC 890, Aspergillus niger KCCM 11240, Saccharomyces cerevisiae IAM 4597, Saccharomyces ellipsoideus PNU 2215. The growth of S. Cerevisiae by treatment of water extract(1%), hexane fraction (0.05%), and estragole (0.05%) were inhibited 93%, 50%, and 33% respectively, and S. ellipsoideus was also inhibited markedly with delaying the alg phase maximum 12 hrs. The growth of A. oryzae was inhibited by treatment of extracts and fractions. The echanol production by S. cerevisiae was increased more than two times in the highest value around 42 hrs incubation by water extract, but chloroform fraction inhibited its production. The glucoamylase actibities by A. niger were strongly inhibited by hexane and chloroform fractions (0.05%). The invertase activity by S. cerevisiae using estragole (0.05%) reached to 57.5% of control group. S. cerevisiae treated with the estragole was damaged the cell wall and cell membrane, leaked the protoplasm, and observed broken pieces of cell.

• 한국지하수토양환경학회:학술대회논문집
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• 한국지하수토양환경학회 2003년도 총회 및 춘계학술발표회
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• pp.413-417
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• 2003

The last few decades have seen drastic growth in the use of brominated flame retardants(BFRs). There is the problems of polybrominated dibenzo-p-dioxins(PBDDS) and polybrominated dibenzofurans(PBDFs) generation as by-products in combustion process of BFRs. PBDDs/PBDFs are highlighted the new pollutants of environmental contamination, recently. In this study, the 10 kinds of PBDDs/PBDFs standards were used to perform the experiments of recoveries. The analysis of PBDDs/PBDFs in soil environmental samples. was carried out. In silica gel column cleanup, PBDDs/PBDFs eluted until 80mL of n-hexane, and the recovery was obtained 73∼105%. In multi-layer silica gel column cleanup, the recovery was obtained 56∼125% with various elution solvents. In alumina clean process, the standard mixture(PBDES, PBDDs/PBDFs) eluted the first fraction of 2% dichloromethane with n-hexane in the range of 0∼100mL, PBDEs compounds eluted in the second fraction of 50% dichloromethane with n-hexane. In activated carbon column cleanup, the PBBEs eluted to the first fraction(n-hexane) and second fraction(toluene), but PBDDs/PBDFs only eluted to the second fraction. The analytical methods of PBDDs/PBDFs for soil was established based on the experimental results of the environmental samples.

• 한국산업보건학회지
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• 제24권3호
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• pp.353-358
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• 2014

Purpose: This study was conducted to evaluate desorption efficiency and storage stability on activated carbon acquired form domestic market. Materials: Mixture of acetone, benzene, normal hexane and toluene was injected on four types of charcoal 100 mg. After overnight, charcoal was desorbed by carbon disulfide $1m{\ell}$ and analyzed by gas chromatography with flame ionization detector. Results: Desorption efficiency of benzene, normal hexane and toluene in charcoal tubes were 95% ~ 105%. But desorption efficiency of acetone in charcoal tubes was below 75% and different from types of charcoal. The more injected amount of acetone on charcoal showed higher desorption efficiency. Acetone injected on charcoal tubes migrated from front section into back section after 10 days storage at room temperature. Conclusions: Desorption efficiency and storage stability of activated carbon acquired from domestic market was good for benzene, normal hexane and toluene. The activated carbon acquired from domestic market has ability to be used as sampling media.

• Food Science and Biotechnology
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• 제18권2호
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• pp.513-518
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• 2009

This study was carried out to investigate the changes of yield, total phenolics, saponin content and composition, antimicrobial, and antioxidant activities of various fractions of fine ginseng root (Panax ginseng C.A. Mayer) by maceration method in the order of increasing polarity (hexane, chloroform, ethyl acetate, butanol, and water). Butanol fraction showed the highest total saponin content compare to other fractions. Hexane fraction could harvest significantly high ginsenoside Rg2, Rg1, and Rf (p<0.05). And the contents of ginsenoside Rh1, Rg3, and Rg1 showed relatively higher in the fraction of ethyl acetate than other fractions. The system of hexane-chloroform-ethyl aceate-butanol showed relatively high content of ginsenoside Re, Rd, Rc, Rb3, and Rb1. However, the last fraction of water still remained lots of Rb2 content. The fraction of water was the highest phenolics. The 1,1-diphenyl-2-picryhydrazil, superoxide, and hydroxyl radical scavenging activity of water fraction was higher than the other fractions. In antimicrobial activity, the fraction of hexane showed relatively high antimicrobial activity against Pseudomonas aeruginosa, Salmonella typhimurium, Staphylococcus aureus, Bacillus cereus, and Escherichia coli. And the fractions of the chloroform and ethyl acetate showed higher antimicrobial activities than the other samples in against P. aeruginosa and S. typhimurium.

• 자연과학논문집
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• 제8권2호
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• pp.21-26
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• 1996

시중에서 판매하는 중국산 옻칠을 그대로 혹은 유기용매에 녹는 부분과 녹지 않는 부분으로 분리하고 각각의 경화현상을 연구하였다. 그대로 사용하는 경우에는 상온에서 수분이 포화된 상태에서 경화를 관찰하였으며 유기용매로 분리한 부분의 경화는 섭씨 $100^{\circ}C$와 $150^{\circ}C$에서 경화를 관찰하였다. 서로 다른 방법으로 얻어낸 도막의 성질을 서로 비교하였으며 옻 중 유기용매에 녹는 부분과 1,6-diisocyanohexane, toluendiisocyanate(TDI)를 공중합하였을 때 얻어지는 도막과 다른 도막과의 성질로 비교하였다. 가열하여 형성된 도막은 매우 깨어지는 성질(취성)이 매우 높았으며 자연상태로 경화된 도막에 비하여 친수성이 낮았다. Diisocyanate를 사용하지 않은 경우에는 경화에 산소가 필수적이어서 오랜 시간이 지나도 내부는 경화가 되지 않았다.