• 한국연초학회지
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• 제25권1호
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• pp.70-79
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• 2003

$\beta$ -Glucosidase-catalysed synthesis of glucosides with aromatic alcohols and monoterpene alcohols as accepters and cellobiose as a donor in the presence of various commercial $\beta$ -glucosidases were described. $\beta$ -Glucosidases from Aspergillus niger spp,. Trichoderma spp., Penicillium sup. and bitter almond have been shown to catalyze synthesis of $\beta$ -glucosides of benzyl alcohol, 2-hydroxybenzyl alcohol, 4-hydroxybenzyl alcohol, 2-phenylethyl alcohol, geraniol and citronellol in the presence of cellobiose as sugar donor. Among enzyme preparations tested, each $\beta$ -glucosides prepared from Aspergillus niger were isolated in the pure state by Diaion HP-20 and silica gel column chromatography. The products were identified as $\beta$ -glucosyl products of benzyl alcohol, 2-hydroxyhenzyl alcohol, 4-hydroxybenzyl alcohol, 2-phenyl ethyl alcohol, geraniol and citronellol by spectrometry (UV, IR, $^1$H-NMR, $^{13}$ C-NMR) and enzymatic hydrolysis with $\beta$ - glucosidase. Monoterpene alcohols with a sterically hindered hydroxyl group, such as linalool, $\ell$-menthol and $\alpha$-terpineol were not used as acceptors in transglycosylation reaction.

• 한국식품영양학회지
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• 제30권1호
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• pp.120-128
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• 2017

This study aimed to provide volatile flavor compounds of three onion products through thermal process and alcohol fermentation, to meet the quality standard of onion products. The identified components of onion extracts (OE) included 49 (18 sulfur-containing compounds, 5 alcohols, 8 acids, 3 ketones, 4 esters, 4 aromatic compounds, 2 aldehydes, 1 pyrazines and 4 miscellaneous compounds), and 55 (17 sulfur-containing compounds, 15 alcohols, 5 acids, 11 ketones, 3 aromatic compounds, 2 aldehydes and 1 pyrazine) in autoclave-sterilized onion extracts (SOE); and 69 (10 sulfur-containing compounds, 27 alcohols, 11 acids, 11 ketones, 6 esters, 1 aromatic compound and 3 pyrazines) in onion wine (OW), respectively. Among the major flavor classes, sulfur-containing compounds (36.8%), acids (31.3%) and aldehydes (13.6%) in OE were changed to alcohols (46.5%) and ketones (27.3%) in SOE whereas, alcohols (56.3%) and acids (26.6%) in OW. Moreover, 1,3-butanediol, 2,3-butanediol, and 3-hydroxy-2-butanone were highly detected in SOE whereas, acetic acid, 3-methylbutanol, 2-phenylethanol and 1,2,3-propanetriol in OW.

• 한국화재소방학회논문지
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• 제7권2호
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• pp.24-28
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• 1993

The flash point for flammable liquids (alcohol, aromatic compounds) were measured by Penskt-Martens's measuring apparatus with closed cup. As a result, it was observed that the flash points had the regular tendency according to the carbon number and the molecular structure. Consequently, the flash point for the alcohols were increased in proportion to the increase of the carbon number and branch number. The differences between the literature and experimental data are 14.6% for the relative error and 3.46$^{\circ}C$ in average for the measuring temperature.

• 한국식품영양과학회지
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• 제28권2호
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• pp.299-304
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• 1999

To compare the composition of volatile flavor components of two different types of rice, the volatile flavor concentrates isolated from brown rices Hyangnambyeo(aromatic cultivar) and Dongjinbyeo (normal cultivar) were analyzed by gas chromatography and gas chromatography mass spectrometry. A total of components, including 16 hydrocarbons, 16 aldehydes and ketones, 15 alcohols, 4 acids, and 10 miscellaneous components were identified positively or tentat ively. Among them, n pentanol was the most abundant component in both samples and Hyangnambyeo contained more aldehydes and alcohols than Dongjinbyeo. 2 Acetyl 1 pyrroline which is chiefly responsible for the character istic odor of aromatic type rice was high in Hyangnambyeo compare to Dongjinbyeo, but these were detected as minor component.

• Bulletin of the Korean Chemical Society
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• 제3권4호
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• pp.149-152
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• 1982

A new convenient method for the reduction of carboxylic acids to the corresponding alcohols via acyloxyborohydrides was explored. Acyloxyborohydrides, prepared from the reaction of various carboxylic acids and sodium borohydride, underwent reduction to the corresponding alcohols readily by the addition of dimethyl sulfate or Lewis acids, such as boron trifluoride etherate and triphenyl borate, presumably through acyloxyboranes. By utilizing this procedure, aliphatic and aromatic acids are rapidly and quantitatively reduced to the corresponding alcohols in terahydrofuran either at room temperature (or at $65^{\circ}$). This procedure provides selective reduction of carboxylic acids in the presence of halogen, nitro, and heterocyclic rings such as furan and thiophene.

• 한국작물학회지
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• 제44권3호
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• pp.181-185
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• 1999

To compare the composition of volatile flavor components of three different cultivars of rice, Hyangnambyeo (aromatic cultivar), Heugjinjubyeo (pigmented cultivar) and Dongjinbyeo (normal cultivar), the volatile flavor components of brown rice were isolated by Likens-Nickerson simultaneous steam distillation and extraction apparatus. The flavor concentrates obtained were analyzed by gas chromatography and gas chromatography-mass spectrometry. A total of 65 components, including 14 aliphatic aldehydes and ketones, 7 aliphatic alcohols, 8 aromatic alcohols, 13 hydrocarbons, 9 esters, 7 aliphatic acids, and 7 miscellaneous components were identified. The aliphatic aldehydes, which are known as contributors to the overall flavor of cooked rice, were present in larger amounts in Hyangnambyeo than in Heugjinjubyeo and Dongjinbyeo, while the difference in quantity of these components between Heugjinjubyeo and Dongjinbyeo was not remarkable. Hyangnambyeo and Heugjinjubeyo contained 562 ng and 259 ng of 2-acetyl-1-pyrroline per gram of brown rice based on dry weight, respectively, which is a key compound contributing to the popcorn-like aroma in aromatic rice. Dongjinbeyo contained about 6 ng.

• Bulletin of the Korean Chemical Society
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• 제31권8호
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• pp.2361-2367
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• 2010

$TiO_2-ZrO_2$ was prepared with surfactant through a sol-gel method. Catalysts containing 5 - 35% $H_3PO_4$ were prepared using these oxides. Subsequently the catalytic performance of prepared catalysts was determined for liquid phase esterification of aromatic acids. $H_3PO_4/TiO_2-ZrO_2$ has been used as catalyst to synthesize various novel esters by esterification of some aromatic acids with aliphatic alcohols (2-propanol, 1-butanol, iso butanol, 3-pentanol, 1-hexanol, heptanol, cyclo heptanol, octanol and decanol). Under optimized conditions, maximum yields and selectivity (100%) to the corresponding ester, was obtained by using 25 wt % $H_3PO_4/TiO_2-ZrO_2$ as catalyst. The Catalyst can be easily recycled after reaction and can be reused without any significant loss of activity/selectivity performance. No by-product formation, high yields, short reaction times, mild reaction conditions, operational simplicity with reusability of the catalyst are the salient features of the present synthetic protocol. The reaction was carried out under solvent-free condition.

• 생명과학회지
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• 제18권11호
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• pp.1570-1577
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• 2008

오만둥이된장찌개의 가열조리에 따른 열유도반응물질을 규명하여 오만둥이를 이용한 가공기술의 기초자료를 제공하고자 향기성분을 분석하였다. 총 128종의 휘발성 향기성분은 에스테르류(16종), 방향족화합물류(14종), 함질소화합물류(11종), 알콜류(34종), 테르펜류(5종), 카르보닐화합물류(23종), 퓨란류(4종), 탄화수소류(13종), 산류(5종) 및 기타화합물류(3종)로 구성되어 있었다. 된장의 향기성분은 방향족화합물, 알콜류 및 산류의 순으로 많았고, 가열 반응 후 pentanoic acid (불쾌취)는 감소하였으며 열유도 화합물인 furfural을 주로 한 퓨란류가 약 2배로 증가하였다. 오만둥이의 향기성분은 decenol, 2,6-dimethylheptanol 및 octanol이 주된 성분인 알콜류, 탄화수소류 및 방향족화합물 순으로 많았다. 가열 반응 후에는 pentanol의 함량이 증가하였고, 함질소아미노산과 카르보닐화합물의 열유도화합물인 2-acetyl-2-thiazoline 및 benzothiazole과 같은 함황고리화합물이 생성되었다. 오만둥이 된장국에서는 오만둥이에서 유리되는 decenol 및 2,6-dimethylheptanol을 주로한 알콜류, 방향족화합물, 탄화수소류 및 된장가열 후 생성된 benzeneacetaldehyde가 주된 카르보닐 화합물이 많았다. 즉 오만둥이 된장국은 독특한 오만둥이향을 함유한 동시에 된장의 구수한 향미를 보유함을 알 수 있었다

• 한국식품조리과학회지
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• 제17권1호
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• pp.55-59
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• 2001

신선 및 동결 건조된 두메부추 잎을 연속수증기 증류추출 장치로 증류하여 얻어진 정유성분을 GC 및 GC-MS로 분석하여 신선한 시료에서 11종의 hydrocarbons 0.136ppm 9종의 aldehydes 0.278ppm, 4종의 alcohols 0.025ppm, 2종의 esters 2.328ppm, 7종의 acids 0.545ppm, 4종의 ketones 0.037ppm 및 9종의 sulfur containing compounds 0.117ppm의 총 46종의 성분을 확인하였다. 동결 건조한 두메부추 잎에서는 8종의 hydrocarbons 1.357ppm 5종의 aldehydes 0.498ppm, 3종의 alcohols 0.094ppm, 5종의 esters 0.720ppm, 2종의 acids 0.069ppm 3종의 ketones 0.163ppm 및 4종의 sulfur containing compounds 0.039ppm을 포함하여 총 30종의 향기성분이 확인되었다. 전자코의 분석 결과, 제1주성분 값의 기여율이 0.987을 나타내어 제1주성분이 두메부추와 부추를 총괄하는 정보로 사용될 수 있음을 알 수 있다. 신선한 두메부추는 제1주성분 값이 0.5부근에 집중된 분포를 보이고, 신선한 부추는 -0.5부근에 분포되어 있어 신선한 두메부추와 신선한 부추의 휘발성 향기성분 패턴이 다름을 알 수 있었다. 또한 동결 건조된 시료의 경우, 두메부추는 제1주성분 값 0을 중심으로 -쪽에 분포되어 있고, 부추는 +부근에 분포되어 있어 동결 건조된 시료의 휘발성 향기성분 패턴도 차이가 있었다.

• Bulletin of the Korean Chemical Society
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• 제34권11호
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• pp.3410-3414
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• 2013

Atom-economical esterification is of great importance in green chemistry. In this work, we demonstrated the catalyst and additive free esterification of alcohols by their reaction with 2-acyl-4,5-dichloropyridazin-3(2H)-ones without solvent at $100^{\circ}C$. Aliphatic and aromatic alcohols were converted into the corresponding esters in good to excellent yields. It is noteworthy that the reaction is solvent-free, atom-economic, easy-workup, and rapid and that the process is inexpensive.