• Korean Journal of Environmental Agriculture
• /
• v.30 no.4
• /
• pp.459-465
• /
• 2011

BACKGROUND: Nowadays, Chemical antiseptics have become great problems for health and environmental, so that developing of new substitutes for chemical antiseptics is more and more important. Natural product is a kind of environment-friendly additive that could be used as antiseptic in food industry. Thuja orientalis cv Aurea Nana is a gymnospermous plant of the family Cupressaceae, native to northwestern China and widely naturalised elsewhere in Korea and Japan. This study was aimed to investigate the antibacterial potential of various organic extracts from T. orientalis cones against some food-borne and food-spoilage bacteria. METHODS AND RESULTS: Hexane extract (HE), chloroform extract (CE), ethyl acetate extract (EAE) and methanol extract (ME) were obtained from female cones of T. orientalis. The antibacterial activities of various extracts were tested by standard agar diffusion and minimum inhibitory concentrations (MICs) against five gram-positive and six gram-negative bacteria. Cell viability and morphology change of L. monocytogenes ATCC 10943 treated with hexane extract were also observed. The various extracts displayed remarkable antibacterial effects against all the gram-positive bacteria but did not show any effect against the gram-negative bacteria. Hexane extract has the highest inhibitory effect on cell viability of L. monocytogenes ATCC 10943. SEM observation also demonstrated the damaging effect of the hexane extract on the morphology of L. monocytogenes ATCC 10943 at the minimum inhibitory concentration. CONCLUSION(s): The tested gram-positive bacteria were significantly inhibited by organic extracts of T. orientalis cone. Hexane extract was the most potent against Listeria monocytogenes ATCC 10943, as evidenced by the lowest MIC level and the complete inhibition of cell viability within shortest exposure time, along with SEM observation.

• Korean Journal of Medicinal Crop Science
• /
• v.25 no.5
• /
• pp.282-289
• /
• 2017

Background: To investigate the possibility of using Asarum sieboldii as an environment-friendly fumigant for protecting organic cultural heritages, the inhibitory effect of A. sieboldii extract against wood rot fungi on Hanji was examined. Methods and Results: The physical, optical, and morphological properties of Hanji inoculated with Trametes versicolor and Tyromyces palustris, and exposed to the n-hexane fraction of A. sieboldii extract, were measured. The physical properties were expressed as weight loss, zero-span tensile strength and viscosity and the optical properties were depicted by luminance and chromaticity ($L^*$, $a^*$, and $b^*$). The results showed that, the n-hexane fraction of A. sieboldii extract inhibited the growth of fungi on Hanji, and preserved its condition. At a concentration of 25 mg, the n-hexane fraction of A. sieboldii extract maintained zero-span tensile strength, increased viscosity, and restricted discoloration of Hanji. It also was confirmed that the weight of fungi infested Hanji exposed to the extract did not decrease. Scanning electron microscopic images revealed that the spores and hyphae of T. versicolor and T. palustris were not present on Hanji during treatment with > 25 mg of the n-hexane fraction of A. sieboldii extract. Conclusions: These results indicate that the n-hexane fraction of A. sieboldii extract by virtue of its antifungal effectiveness may help in preserving Korean paper cultural heritages, including Hanji.

• Analytical Science and Technology
• /
• v.19 no.6
• /
• pp.512-518
• /
• 2006

The evidence containing some kind of petroleum at the fire spot was analyzed by gas chromatography to identify a fire's sources. To extract some petroleum from fire evidence, 10.0 mL of n-hexane was added in this solution, and it was shaken for 30 minutes. To identify a kind of petroleum in fire evidence, the prepared n-hexane solution was injected and analyzed in the gas chromatograph. The chromatogram of sample was different from those of thinner and gasoline that have low boiling point, and shown different peak pattern to heating and boiler oils. But it was similar to the chromatogram of diesel oil. After small amount of diesel oil was added to the sample, the area of characteristic peaks was increased more than those of raw sample. From the results, the kind of petroleum in the fire evidence was diesel oil.

• Korean Journal of Food Science and Technology
• /
• v.4 no.3
• /
• pp.206-212
• /
• 1972

Oxidative changes in the rice lipids under accelerated condition were studied by measuring the changes in weight gain, total carbonyl compound, malonaldehyde, and fatty acid composition. Rice lipids were prepared by extraction with either n-hexane or ethanol from polished rice grain and purified by Folch's method. The lipid preparations were either incubated in dark at $40^{\circ}C$ or irradiated with ultra-violet light for a period of 55 days. Weight gain by oxygen absorbed sharply increased within 3 days in the rice lipids under UV light irradiation. However, with the rice lipids at $40^{\circ}C$ incubation a moderate increase in weight was observed only after 45 days storage. Their induction periods were one day (hexane extracted, under UV light), 2 days (ethanol extracted, under UV light), 30 days (hexane extracted, at $40^{\circ}C$), and 40 days (ethanol extracted, at $40^{\circ}C$) respectively. Oxidative rancid odor appeared at the end of the induction period. Total carbonyl compound and malonaldehyde markedly increased within 7 days, and decreased in the rice lipids under ultra violet light irradiation, while at $40^{\circ}C$ incubation they were continued to increase slowly through out the storage. The hexane extracted lipid were less stable than ethanol extracted lipid on the basis of oxygen absorption, malonaldehyde and other carbonyl compound formation. With the hexane extracted lipid during 55 days incubation at $40^{\circ}C$, the contents of linoleic and linolenic acids decreased, while the oleic, stearic, and palmitic acids increased.

• Bulletin of the Korean Chemical Society
• /
• v.34 no.9
• /
• pp.2623-2628
• /
• 2013

Three di-acyl chlolide reagents, adipoyl chloride, terephthaloyl chloride and isophthaloyl chloride, were used as spacer reagents to prepare bonded type of three cellulose (3,5-dimethylphenyl)carbamate (CDMPC) chiral stationary phases (CSPs). The CDMPC CSPs were prepared using these three acid chlorides as spacer agents at the 6-position of the primary hydroxyl group on the glucose unit of cellulose regioselectively. The chiral recognition ability of the prepared CSPs for five racemates was evaluated by normal-phase high-performance liquid chromatography (HPLC) with the following mobile phases: hexane/isopropanol (IPA), hexane/IPA/tetrahydrofuran (THF) and hexane/IPA/chloroform. The result showed that these prepared CSPs can be used in THF and chloroform solutions and the chiral recognition abilities of the CSPs were improved depending on the eluents and chiral samples.

• Journal of Industrial Technology
• /
• v.20 no.A
• /
• pp.203-209
• /
• 2000

The fluctuation integrals which give useful information in the structure of solution are associated with the mixed direct correlation integral ($C_{12}$) known. Using its weighted arithmetic mean of $C_{11}$ and $C_{22}$ and the activity coefficient model, the fluctuation integrals on solute-solute, solvent-solute, and solvent-solvent can be calculated in the function of mole fraction. In this work, several binary mixtures containing c-hexane were tested and the results on the fluctuation integrals were rather good.

• Environmental Analysis Health and Toxicology
• /
• v.1 no.1
• /
• pp.55-60
• /
• 1986

The writer measured methemoglobin formation with solvent (n-hexane, ethylacetate and methanol) organic extracts from the sediments of the Wonju stream run through Wonju city on Octover 2nd, 1985. Hemoglobin was converted to methemoglobin with the n-hexane extract obtained from the sediment of the St. C and St. D was polluted industrial wastewater, but not with that from the St. B was polluted with the urban wastewater. The formation of methemoglobin was remarkable with the all solvent extracts from the sediment of the uper stream of the Wonju stream. Doses of the solvent extracts for 20% methemoglobin formation in the researched Wonju streams were as follows; 0.095～0.28 mg/m.$\ell$ in n-hexane extract. 0.85-1.3 mg/ m$\ell$ in methanol extract and 1.95～2.80 mg/m$\ell$ in ethylacetate extract.

• 한국생물공학회:학술대회논문집
• /
• 2001.11a
• /
• pp.693-696
• /
• 2001

Ketoprofen racemate is very useful pharmaceutical intermediate, but the hardness of separation to each enantiomer is most a barrier to apply pharmaceutical industry. To overcome this difficulty, we would like to separate S-ketoprofen from ketoprofen racemate. To design suitable mobile phase, hexane and t-BME(tri-buthyl-methyle-ether) were used to elute peaks of ketoprofen racemate separately. When the ratio of hexane/t-BME/acetic acid was 60/40/0.1(%v/v), each component was separated successfully. In order to separate large amount of S-ketoprofen, sample concentration was increased from 100ppm to 2000ppm. In this case, resolution was decreased due to the overlapping of peaks(1.65${\rightarrow}$0.94).

• Journal of Life Science
• /
• v.9 no.2
• /
• pp.207-211
• /
• 1999

Biologically active compounds in Polygonatum sibiricum were extracted using organic solvents as hexane, CHCl$_3$, n-butanol corresponding each component. Compound I was purified from hexane layer and the chemical structure of compound I was characterized using 1H-NMR, 13C-NMR, DEPT135, COSY, HMQC, HMBC spectrum and MS-spectrum. Consequently, the chemical structure of compound I was determined as 9,12-(9E,l2E)-octade cadienoic acid.

• 한국신재생에너지학회:학술대회논문집
• /
• 2006.11a
• /
• pp.58-61
• /
• 2006

n-Pentane and n-hexane, previously regarded as non-hydrate formers, are found to form structure H hydrate in mixtures with 2,2-dimethylbutane. Even though they are thought to be too large to fit into the largest cage of the structure H hydrate, powder XRD and NMR measurements show that they form gas hydrates in mixtures with other sH hydrate former. These findings are of fundamental interest and also will impact the composition and location of natural gas hydrates and their potential as global energy resource and climate change materials.