• Journal of the Korean Chemical Society
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• v.56 no.6
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• pp.706-711
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• 2012

Hindered phenols and alcohols were protected as their corresponding ethers using different alkylating agents in presence of KOH/DMSO under microwave irradiation. $$R-OH\;{KOH/DMSO,\;R^{\prime}-X,\;MW \\{\vec{10-15\;Mins,\;80%-90%\;Yield}}}\;R^{{/}^O{\backslash}}R^{\prime}$$.

• Bulletin of the Korean Chemical Society
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• v.30 no.5
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• pp.1071-1076
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• 2009

N,N,N′,N′-tetramethylethylenediamine (TMEDA) acts as a simple, mild and efficient catalyst for the acylation of alcohols, phenols and thiols at room temperature under solvent-free condition. Acylation reaction with acetic anhydride and benzoic anhydride proceeds with good to excellent yield in the presence of TMEDA as the catalyst.

• Applied Biological Chemistry
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• v.31 no.3
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• pp.292-297
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• 1988

The volatiles of whole and homogenated tomato fruits collected by the headspace trapping method using Tenax GC and the simultaneous steam distillation method were identified by GC and GC-MS. Among over 100 GC peaks, 10 alcohols, 6 aldehydes, 4 ketones, 3 esters, 1 phenol and 1 acid were identified from whole tomato fruits, whereas 12 alcohols, 6 aldehydes, 5 ketones, 5 esters, 2 phenols, 1 hydrocarbon and 1 acid were identified from homogenated tomato fruits. By simultaneous steam distillation-extraction, 19 alcohols, 13 hydrocarbons, 9 esters, 9 ketones, 8 aldehydes, 2 phenols, 2 lactones,2 furans, 1 acids and 2 others were identified among over 300 peaks.

• Journal of the Korean Chemical Society
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• v.55 no.4
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• pp.633-637
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• 2011

Iron (III) phosphate was employed as an efficient catalyst for the chemo selective acetylation of alcohols and phenols under solvent free condition at room temperature and with high yields. Iron (III) phosphate is also a potential green catalyst due to solid intrinsically, reusable and with high catalytic activity.

• Bulletin of the Korean Chemical Society
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• v.22 no.11
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• pp.1177-1178
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• 2001

• Bulletin of the Korean Chemical Society
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• v.1 no.4
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• pp.144-144
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• 1980

• Preventive Nutrition and Food Science
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• v.6 no.1
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• pp.10-15
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• 2001

Antimicrobial activities of volatile flavor, water and methanol extracts from Agastache rugosa were investigated. The volatile flavor extract was obtained from A. rugosa by simulataneous distillation-extraction (SDE) method. Antimicrobial activity was investigated by disc diffusion method against several microorganisms, four species of Gram positive, three species of Gram negative and tow species of yeast. The volatile flavor extracts had strong antimicrobial activity againstc. utilisand S. cerevisiae. During the growth period, a difference in antimicrobial activity among volatile flavor extracts from A. rugosa was not shown. The water extract of above 10 mg/disc showed antimicrobial activity. Methanol extracts from A. rugosa harvested in June showed antimicrobial activity against tested Gram positive and Gram negative bacteria, showed weak antimicrobial activity against the bacteria from those harvested in July and August. In particular, antimicrobial activity against V. parahaemolyticus was stronger than that against other bacteria. Water and methanol extracts did not inhibit yeast. C. utilis and S. cerevisiae. To further elucidate the effective components, volatile flavor extracts was analyzed by GC/MS. harvested in June, the components included 8 phenols (93.031%), 18 terpenes (5.230%), 12 alcohols (1.300%) 8 alkanes (0.181%), 1 ester (0.056%), 2 ketones (0.033%), 2 aldehydes (0.011%) and 1 pyrrole (0.007%). In July, the components included 6 phenols (94.366%), 19 terpenes (3.394%), 11 alcohols (2.045%), 1 ester (0.039%), 2 ketones (0.028%), 1 furan (0.005%) and 1 aldehyde (0.005%). And in August, the components included 7 phenols (95.270%), 19 terpenes (2.951%), 13 alcohols (1.399%), 1 ester (0.063%), 2 aldehydes (0.016%), 2 ketones (0.011%), 1 alkane (0.006%), 1 acid (0.005%) and 1 pyrrole (0.005%). The major component of volatile flavors was estragole, a phenolic compound.

• Journal of the Korean Society of Tobacco Science
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• v.24 no.1
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• pp.53-59
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• 2002

This study was conducted to evaluate whether pine needle extracts can be used as tobacco flavors. Yield of essential oil, absolute and oleoresin extracted from pine needles is 0.07%, 1.20% and 6.08% respectively. The volatile compounds isolated from the three types of extracts were analyzed by gas chromatography(GC) and mass selective detector(MSD). Total 72 components were identified in the three type of extracts including 26 hydrocarbons, 16 alcohols, 13 esters, 9 acids, 4 phenols, 2 aldehydes and 2 ketones compounds. The major components were $\beta$-pinene, $\beta$-caryophyllene, $\delta$-cadinene and 4,5-dimethyl-1,3 -dioxol-2-one. There were 49 volatile components in the absolute, 44 components in the essential oil and 26 components in the oleoresin. The content of hydrocarbons and alcohols was higher in the essential oil extracted by simultaneous distillation extraction(SDE) than in others, while that of esters and acids was higher in the absolute than in others. Especially, phenols and ketones were identified only in the oleoresin. The components such as $\beta$-pinene, bornyl acetate, $\alpha$-terpineol and oxygenated terpenes have characteristic piney and fresh green odor. The contents of these components was higher in the essential oil and the absolute than in the oleoresin. Therefor, the essential oil and the absolute are expected to be more useful than the oleoresin as tobacco flavor.

• Preventive Nutrition and Food Science
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• v.4 no.1
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• pp.18-22
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• 1999

Flavor characteristics of raw Cordyceps militaris significatntly different from those of dried one. In the case of raw Cordyceps militaris , major flavor components were composed of 5 alcohols, 3 ketones, 4 phenols, 9 alkanes , and 3 alkenes. The major alcohol was 1-octen-3-ol(22.56%, 1147.3% ng/ml), which contributed to the characteristic green flavor. Ketones (3-ocatone, inparticular )were present in the highest concentration in raw Cordyceps militaris . In contrast, major flavor components of dried Cordyceps militaris were composed of 4 alcohols, 4 ketones, 3 furans, 4 pyrizines, 2 dithiazines, 5 phenols , 8alkenes , 17 alkanes, and 8 fatty acids. Dried Cordyceps militaris had unique sweet aroma of sesame as wella s a milky flavor. Green or fruit flavor were rarely detected . In alkanes , 10 cosanes, component fo wax were present. Typical flavor components of alkanes such as $\beta$-caryophyllen and Δ-cadinene were also detected. Fatty acids of dried Cordyceps militaris ranged from myristic acid (14 :0) to linoleic acid (18 ; 2). The sweet aroma of dried Cordyceps militaris was mostly due to pryazines, dithaiazines, and furans. Two dithaizines were identified and characteristics of these flavor components was a roasted bacon flavor. Strong antibacterial acitivity was observed toward Vibrio spp. such as V. vulnificus, V.cholerae, V. parahaemlyticus. Relatively high antibacterial acitivity was shown toward Bacillus subtilis , B,cereus, Staphyllococcus aureus, and Corynebacterium xerosis.

• Korean Journal of Food Science and Technology
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• v.21 no.4
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• pp.511-514
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• 1989

Volatile components of Youngia denticulata and Amaranthus lividus, Korean wild vegetables, were collected by Steam Distillation-Extraction (SDE) method Essential oils were analyzed by gas chromatography (GC) and combined gas chromatography-mass spectrometry (GC-MS). Thirty one components, Including 10 alcohols, 2 esters, 6 aldehydes, 5 ketones, 3 hydrocarbons, 2 acids and 3 miscellaneous ones were confirmed in Youngia denticulata. Fifty eight components, including 12 alcohols, 4 esters, 5 aldehydes, 9 ketones, 3 acids, 2 phenols and 6 miscellaneous ones were confirmed in Amaranthus lividus.