• Korean Journal of Food Science and Technology
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• v.52 no.5
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• pp.524-528
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• 2020

The aim of this study was to enhance the use of wheat bran in lactic acid bacteria (LAB) fermentation. LAB fermentation of wheat bran and the flavor components and amino acids of fermentation products were analyzed using gas chromatography-mass spectrometry (GC/MS) and high-performance liquid chromatography (HPLC). The results showed that total flavor components increased by 93% and 73% in the animal-based LAB mixture (T2) and plant-based LAB mixture (T3), respectively, after fermentation. Among these components, 2,3-butanedione (diacetyl), known for its buttery flavor, was detected at concentrations of 18.44 ng/g (T2) and 16.95 ng/g (T3). Levels of hexanal and nonanal, which causes off-flavor components in wheat bran, dramatically decreased after T2 fermentation; similarly, levels of total free amino acids decreased by 37.6% (T2) and 36.7% (T3) after fermentation. This may explain why some components were bound to volatile compounds during LAB fermentation. These results suggest that LAB-fermented wheat bran is a potential value-added food material.

• Food Industry
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• s.172
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• pp.38-56
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• 2003

The volatile compounds of traditional Kyungsando squid sikhe were identified by GC-MS. the amount of-zingibirene among identified volatile compounds was 19.73 mg/kg. The major volatile compounds of sikhe was (Z)-Di-2-propenyl disulfide,-curcumene, methyl

• Korean Journal of Environmental Biology
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• v.35 no.2
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• pp.123-127
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• 2017

To determine their acute toxicities on the earthworm (Eisenia fetida), six toxic chemicals were evaluated, according to the OECD guideline 207: sulfuric acid, methanol, methylethylketone, nitric acid, formic acid, and toluene. Sulfuric acid exhibited the maximum toxicity. The $LC_{50}$ values of sulfuric acid, nitric acid, formic acid, and toluene were 20.5, 49.1, 55.5, and $534.5{\mu}g\;cm^{-2}$, respectively. Toluene showed 26-fold lower toxicity than sulfuric acid. In this study, methanol and methylethylketone did not exhibit any toxicity to the earthworm. Further evaluation revealed that nitric acid, formic acid, and toluene exerted a change in the body weight of the chemically treated earthworms, whereas the other chemicals were ineffective. These results can be used for environmental risk assessment, when the chemicals are accidently discharged into the environment.

• The Korean Journal of Pesticide Science
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• v.2 no.2
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• pp.16-21
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• 1998

Bis-aromatic ${\alpha},{\beta}$-unsaturated ketone derivatives represented as substrate(S) were synthesized and their fungicidal activities in vivo against rice blast(Pyricularia oryzae) and tomato leaf blight(Phytophthora infestans) were examined with the quantitative structure activity relationships(QSAR) using 3D QSAR, comparative molecular field analysis (CoMFA). The 3D CoMFA results and those of 2D QSAR were compared and the results reveal that both results show similar trend. The two important factors, steric and electronic, contribute toward the activity. We assumed that fungicidal activity for rice blast was greatly improved by increasing with positive charge of ${\beta}$-carbon and introduction of bulky derivatives into $R_{2}$ group, while that for tomato leaf blight was improved by decreasing the positive charge of ${\beta}$-carbon and introduction of smaller molecular derivative into $R_{2}$ group. The CoMFA analyses clearly demonstrate its potential in unraveling the steric and electronic features of the molecules through contour maps.

• Journal of Energy Engineering
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• v.25 no.3
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• pp.66-72
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• 2016

In this study, a sulfonated poly(arylene ether ketone) block copolymer was prepared from hydrophilic oligomer and hydrophobic oligomer. The structure of the prepared membrane was characterized by $^1H$-NMR, FT-IR and GPC. The $M_w$(weight-average molecular weights) of the polymer was $209,700g\;mol^{-1}$ and the molecular weight distribution($M_w/M_n$) of 1.25 was obtained. The prepared membrane showed excellent thermal stability with gradual weight loss up to $200^{\circ}C$. The proton conductivity of SPAEK block copolymer reached the maximum of $9.0mS\;cm^{-1}$ at $90^{\circ}C$ under 100% relative humidity (RH). From the observed results, it is necessary to do more aggressive attempt to study the possibility of application as an ion-conductive composite electrolyte.

• Journal of the Korean Chemical Society
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• v.31 no.4
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• pp.359-363
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• 1987

Sonic waves (50KHz) was accelerated the oxidation reaction of primary, benzyl and secondary alcohol with $BaMnO_4\;and\;KMnO_4-CuSO_4{\cdot}5H_2O$ to give the corresponding aldehyde and ketone at $30^{\circ}C/1$ atm. in high yields compared to stirring or refluxing condition.

• Proceedings of the Membrane Society of Korea Conference
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• 1993.10a
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• pp.32-33
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• 1993

근래 환경 문제의 중요성이 크게 대두되면서 여러 제조 공정에서 방출되는 폐수등을 처리하는데 막분리 공정을 이용하려는 연구가 진행되고 있다. 이 공정에 필요한 내구성, 내 미생물성, 내 약품성등이 우수한 역삼투막 재료를 얻기 위한 방법의 하나로 엔지니어링 플라스틱을 친수화 시키는 방법이 개발되어 왔는데, 구체적으로는 설폰화등의 친수화가 된 폴리설폰(polysulfone), 폴리 에테르 에테르 케톤(poly ether ether ketone), 폴리 이미드(polyimide) 수지등이 검토되고 있다. 특히 PPO(poly(2,6-dimethyl-1,4-phenylene oxide))로 만들어진 분리막은 내산화성이 우수하고 내구성이 뛰어나다고 알려져 있다. 본 연구에서는 PPO를 유기 금속 반응을 이용하여 carboxylation시키고 이 carboxylated PPO로 역삼투막을 제조하여 투과특성을 조사하였다.

• Polymer(Korea)
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• v.31 no.2
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• pp.93-97
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• 2007

Phenyl styryl ketone ligands 1-5 containing different functional groups were synthesized and attached to the aminated poly (styrene-divinvlbenzene) copolymer through diazotization. The coupling of the ligand with polymer was confirmed by FT-IR. The variation of the uptakes of Pb (II) or Cu (II) ions loaded in the prepared polymers (6-10) was examined at different pH values. An increase of metal uptake in the polymers was observed with the increase in pH value in aqueous solution.

• Journal of the Korean Society of Industry Convergence
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• v.26 no.3
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• pp.371-380
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• 2023

This study aimed to present data for the industrialization of Omija added onion fermented beverage (OOFB) development by analyzing the volatile flavor components. A total of 55 compounds, including 4 terpene derivatives, 9 esters, 5 aromatic compounds, 6 alcohols, 7 ketones, 3 aldehydes, 11 acids, 1 sulfur-containing compound, 8 furans and 1 other, were identified in OOFB. The content of fragrance components was high with 37.8% of acids and 29.0% of furans. 2,5-dimethyl thiophene, a sulfur compound, is a compound produced during the acetic acid fermentation of onion, and is thought to affect the onion flavor of OOFB.

• Korean Journal of Food Science and Technology
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• v.39 no.2
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• pp.109-113
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• 2007

Adenophora remotiflora (Mosidae) is a perennial plant in the Campanulaceae family and a wild plant that only inhabits in Korea. This research analyzed the volatile compounds in Mosidae and their antioxidant activities. The volatile compounds in fresh, shady air-dried, and freeze-dried Mosidae were isolated by steam-distillation extraction (SDE) method using diethylether as a solvent. Volatile compounds were analyzed by gas chromatography-mass spectrometry (GC/MS). Antioxidant activities were determined using the linoleic acid system and 1,1-diphenyl-2-picrylhydrazyl (DPPH) method. Sixty and seventy-two volatile compounds were identified from fresh and shady air-dried Mosidae, respectively. In fresh Mosidae, the most abundant compounds were ethyl acetate and heptyl acetate, while ethyl acetate and limonene were the most abundant in the shady air-dried sample. Inhibition of peroxide formation by fresh Mosidae was higher than that of ${\alpha}-tocopherol$, and inhibition by shady air-dried Mosidae was same as that of ${\alpha}-tocopherol$. Furthermore, volatile compounds from shady air-dried Mosidae had higher free radical scavenging activity than ${\alpha}-tocopherol$. The freeze-dried sample showed lower antioxidant activity in both the linoleic acid system and DPPH method.