• Journal of the Korean Society of Tobacco Science
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• v.20 no.2
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• pp.210-217
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• 1998

Volatile flavor components of extracts produced from the domestic angelica root, which are oleoresin and absolutes type, for tobacco flavoring materials were isolated by solvent extraction method and were analyzed by GC and GC/MSD. And then volatile flavor components of oleoresin were compared with volatiles isolated from absolutes. A total of 65 components were identified in the angelica root extracts, from which 41 components were identified in the oleoresin volatiles, contained 15 hydrocarbons, 12 alcohols, 6 acids, 10 esters and 2 miscellaneous components. The major components were hexadecanoic acid (7.79%), methyl palmitate (6.49%), ethyl palmitate (2.02 %) and sesquiterpenes and sesquiterpene alcohols, such as elemol (2.92 %), ${\gamma}$-selinene (2.19%), $\beta$-selinene (2.02%), $\alpha$-eudesmol (3.49%) and $\beta$-eudesmol (6.12%). On the other hand, volatiles of absolutes, from which 60 components were identified, contained 28 hydrocarbons, 14 alcohols, 5 acids, 10 esters and 3 miscellaneous components. The major components were hyrocarbons, such as undecane (5.11 %), dodecane (3.10%) and pentadecane (1.14 %), and $\alpha$-muurolene (1.64 %), ${\gamma}$-selinene (1.49%), $\beta$-selinene (2.12 %), $\alpha$-eudesmol (2.25%), $\beta$-eudesmol (4.87%), hexadecanoic acid (12.67%) and hexanoic acid (1.87 %).

• Bulletin of the Korean Chemical Society
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• v.25 no.6
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• pp.847-851
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• 2004

The complexation characteristics of tetramethyl (1) and tetraethyl esters (2) of p-tert-butylcalix[4]arene with alkali metal cations have been investigated by ab initio calculation. The structures of endo- or exocomplexation of the hosts in cone conformation with alkali metal ions have been optimized using HF/6-31G method followed by B3LYP/6-31G(d) single point calculation. B3LYP/6-31G(d) calculations suggest that exo-complexation efficiencies of sodium ion to the cavity of lower rim of hosts 1 and 2 are 27.1 and 25.8 kcal/mol better than that of potassium ion, respectively. The exo-complexation efficiencies of potassium ion to the cavity of lower rim of hosts 1 and 2 are 33.3 and 31.5 kcal/mol better than the endo-complexation inside the upper rim (four aromatic rings) as expected from the experimental results. B3LYP/6-31G(d) calculation of the ethyl ester 2 shows 29.5 and 30.8 kcal/mol better exo-complexation efficiency for both sodium and potassium ions than the methyl ester 1.

• Journal of the Korean Society of Food Culture
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• v.36 no.3
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• pp.317-324
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• 2021

This study was carried out to investigate the flavoral essential oil components in the stems of Agastache rugosa. These components were analyzed using gas chromatography-mass selective detector (GC-MSD). The stems of Agastache rugosa were contained alcohols, aldehydes, ketones, fatty acid esters, and terpenoids. The peak area (%) of estragole was highest among its oil components and the next were pulegone and menthone. The terpenoid alcohols found were 1-octen-3-ol, chavicol, spatulenol, 3-hexen-1-ol, 2-cyclohexen-1-ol, methyl eugenol, and octaethyllene glycol. The stems also contained ketones such as pulegone, menthone, cis-isopulegone, 2-cyclohexene-1-one, 3-octanone, 1-cyclohexanone, isoindole-1-one, t-ionone, inden-2-one, as well as the aldehydes of 4-methoxycinnam and benzaldehyde. The following esters were also detected 1-isopulegone-3-yl acetate, caryophyllene oxide, acetate and benzendicarboxylic acid ester. The terpenoids in the stems were identified as caryophyllene, limonene, cyclohexasiloxane-D, germacrene-D, anethole, cadinene, muurolene, and bourbonene. Overall Agastache rugosa contained several functional oil components including phenylpropanoids and terpenoids as flavoral essential oil components for natural aromatherapy.

• Journal of Microbiology and Biotechnology
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• v.26 no.2
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• pp.315-325
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• 2016

A novel esterase gene, est7K, was isolated from a compost metagenomic library. The gene encoded a protein of 411 amino acids and the molecular mass of the Est7K was estimated to be 44,969 Da with no signal peptide. Est7K showed the highest identity of 57% to EstA3, which is an esterase from a drinking water metagenome, when compared with the enzymes with reported properties. Est7K had three motifs, SMTK, YSV, and WGG, which correspond to the typical motifs of family VIII esterases, SxxK, Yxx, and WGG, respectively. Est7K did not have the GxSxG motif in most lipolytic enzymes. Three additional motifs, LxxxPGxxW, PLGMxDTxF, and GGxG, were found to be conserved in family VIII enzymes. The results of the phylogenetic analysis and the alignment study suggest that family VIII enzymes could be classified into two subfamilies, VIII.1 and VIII.2. The purified Est7K was optimally active at 40ºC and pH 10.0. It was activated to exhibit a 2.1-fold higher activity by the presence of 30% methanol. It preferred short-length p-nitrophenyl esters, particularly p-nitrophenyl butyrate, and efficiently hydrolyzed glyceryl tributyrate. It did not hydrolyze β-lactamase substrates, tertiary alcohol esters, glyceryl trioleate, fish oil, and olive oil. Est7K preferred an S-enantiomer, such as (S)-methyl-3-hydroxy-2-methylpropionate, as the substrate. The tolerance to methanol and the substrate specificity may provide potential advantage in the use of the enzyme in pharmaceutical and other biotechnological processes.

• Journal of the Korean Society of Food Science and Nutrition
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• v.34 no.6
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• pp.885-891
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• 2005

The study was carried out to find the effect of freeze drying on the volatile organic components in garlic (Allium sativum L.). The volatile organic compounds from fresh and freeze dried garlic were extracted by simultaneous steam distillation and extraction (SDE) method and identified with GC/MS analysis. A total of 42 and 32 compounds were identified in fresh and freeze-dried garlic, respectively. Sulfur containing compounds in the garlic samples were detected as the major compounds, and alcohols, aldehydes and esters were detected as minor compounds. Diallyl disulfide, diallyl trisulfide, allyl methyl disulfide and ally1 methyl trisulfide were the main sulfur compounds in fresh and freeze dried garlic. The amount of sulfur containing compounds were decreased freeze-drying but methyl propyl trisulide, 3- allylthiopropionic acid, cyclopentyl ethyl sulfide etc. were increased. The others, non- sulfur containing compounds such as ethyl acetate, ethanol, 2-propenol, 2- propenal and hexanal were increased in freeze-dried garlic. Consequently, the total amount of volatile organic compounds in garlic became lower during freeze-drying from 853.42 mg/kg to 802.21 /kg, and the composition of major components were nearly same in fresh and freeze-dried garlic.

• Journal of the Korean Society of Food Science and Nutrition
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• v.42 no.6
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• pp.933-940
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• 2013

In this study, methyl esters with different saturated fatty acids (SFA) were prepared by urea fractionation to make an oil-in-water emulsion. Emulsion characteristics (emulsion stability and oxidative stability) of the methyl ester emulsion were then studied at different percentages of methyl ester saturation (5, 28, 39, 50, and 72%, termed ${\Sigma}$SFA5, ${\Sigma}$SFA28, ${\Sigma}$SFA39, ${\Sigma}$SFA50, and ${\Sigma}$SFA72, respectively). The stability of emulsions (ES) with different SFA content was 46.0 (${\Sigma}$SFA5), 39.5 (${\Sigma}$SFA28), 32.7 (${\Sigma}$SFA39), 32.6 (${\Sigma}$SFA50), and 27.3 (${\Sigma}$SFA72). Results from Turbiscan showed that creaming or clarification, based on the backscattering intensity, was more pronounced with increases in the saturation degree of the emulsion. These results implied that the emulsions with lower saturation were more stable. During 30 days of storage, the lipid peroxide value increased for all emulsions, with the increase less pronounced with the increasing saturation of the emulsion; 1.880 (${\Sigma}$ SFA5), 1.267 (${\Sigma}$SFA28), 1.062 (${\Sigma}$SFA39), 0.342 (${\Sigma}$SFA50) and 0.153 (${\Sigma}$SFA72) mg $H_2O_2/mL$ emulsion. In addition, thiobarbituric acid reactive substances (TBARS) values were significantly lower in emulsions with high saturation (4.419 mg for ${\Sigma}$SFA50 and 4.226 mg for ${\Sigma}$SFA72) than emulsions with low saturation (6.229 mg for ${\Sigma}$SFA5, 6.801 mg for ${\Sigma}$SFA28 and 6.246 mg for ${\Sigma}$SFA39). In conclusion, the emulsions with a higher saturation degree of methyl esters showed lower emulsion stability but better oxidation stability.

• Journal of the Korean Society of Food Culture
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• v.12 no.2
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• pp.173-182
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• 1997

This study was carried out in order to investigate effective aroma components of Korean traditional soy sauce. Volatile aroma compounds were extracted by solvent extraction, TMS esterification of methyl acetate extracts and SDE, and analyzed by GC/MSD. 140 voltile aroma compounds were detected by three different extraction methods. Most abundant volatile compounds were acids and phenols and identified aldehydes, hydrocarbons, ketones, furans, furanone, alcohols, esters, nitrogen compounds, sulfur compounds and thiazoles, too. In the analytical sensory evaluation of soy sauce aroma, there were significant differences between each soy sauce sample in all test item. To sum up, Sweet odor was high in Kyupjang. Nutty odor and traditional soy sauce odor were similarly high in Kyupjang and high concentration soy sauce. Kyupjang had high score in overall odor preference than Chungiangs. The result of multiple regression of soy sauce odor characteristics and gas chromatography pattern demonstrated that offensive and sour odor was affected by octadecanoic acid. Contributive compounds to sweet odor were 1,2-benzenedicarboxylic acid and 3,6-dioxa-2,7-disilacotane. Benzoic acid 4-methyl ethyl ester and nonacotane were identified as major compounds of nutty odor. Contribu live variables of traditional soy sauce odor were benzoic acid 4-methyl ethyl ester and 9,12-octadecadienoic acid. The main factors of odor preference were 3-methyl pentanoic acid, acetic acid, 2,6-dimethyl heptadecane and 3,6-dioxa-2,7-disilacotane.

• Food Science and Preservation
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• v.12 no.1
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• pp.68-74
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• 2005

This study was carried out to analyze to the flavor components of Lindera obtusiloba BL leaf teas by different processing methods. 81 kinds of flavor components in the masted tea, 78 in the roasted tea after steaming, 88 in the withered tea, 86 in the fermented tea, 72 in the steamed tea, and 89 in the air dried tea ware by GC/MS. Hydrocarbones in Lindera obtusiloba BL leaf teas were 45 kinds of $\beta-piepne$, and 16 kinds of alcohols such as Linalool, n-octanoal, phenyl acetaldehyde, $(-)-\alpha-terpineol$, elemol, and cholest-5-en-3-ol. 11 kinds of ketones sachas 2-ethyl-2- propyl-cyclohexanone, and 8 kinds of aldehydes sach as phenyl acetaldehyde, tetradecanal, 10-undecanal, 4-Bromo-2-methylbutanal were found. Esters were methyl 9,12,15-octadecatrienate, didodecyl phthalace, 1,2-benzenediccarbaboxy acid-bis (2-ethylhexyl)ester and phenols was 2,6-bis(1,1-dimethylethyl)-4-methyl-phenol.

• Korean Chemical Engineering Research
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• v.46 no.4
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• pp.747-751
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• 2008

The effect of additives in the synthesis of biodiesel fuel using supercritical methanol was studied in order to examine the possibility of application of spent vegetable oil as a raw material, which has high contents of water or free fatty acid. The experiments were performed by varying the contents of water, free fatty acid or antioxidants respectively in a batch reactor. The contents of fatty acid methyl ester was analyzed by a gas chromatography. As the water contents increased, the contents of fatty acid methyl ester decreased, however, the decrease was very little compared with the alkaline and acid catalyst. The effect of the contents of free fatty acid, vitamin E, and ${\beta}$-carotene was negligible.

• The Korean Journal of Food And Nutrition
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• v.13 no.5
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• pp.453-459
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• 2000

In order to promote the utilization of Rubus coreanum as functional food, and its physicochemical properties and volatile flavor were examined. The contents of chemical compounds showed 5.39% of moisture, 17.3% of total sugars, 8.6% of reducing sugars, 4.5% of crude ash, 3.9% of crude fiber, 10.6% of crude protein and 1.7% of crude fat and that of free sugars was 1.52% of sucrose, 3.98% of fructose, 1.24% of glucose. Among organic acid was 10.2% of citric acid, 6.29% of oxalic acid and 1.94% of malic acid. The highest component of free amino acids was 1,260.3mg of aspartic acid, 1,054.3mg of glutamic acid, respectively. And that of minerals was 38,789ppm of K. A total of 52 volatile flavor components (11 alcohols, 13 acids, 20 carbonyls, 5 hydrocabons, 3 esters) were identified in the Rubus coreanum, respectively. The major volatile flavor components of Rubus coreanum were 3.78% of linalool in alcohols, 14.40% of caproic acid in acids, 2.99% of 2-hydroxy-4-methoxyacetophenone in carbonyls, 1.59% of aromadendrene in hydrocabons and 0.43% of methyl palmitate in esters.