• Bulletin of the Korean Chemical Society
• /
• v.15 no.8
• /
• pp.644-649
• /
• 1994

The approximate rates and stoichiometry of reaction of excess dipyrrolinoaluminum hydride (DPAH) with selected organic compounds containing representative functional groups under standardized conditions (tetrahydrofuran, 0, reagent : compound=4 : 1) were examined in order to define the characteristics of the reagent for selective reductions. The reducing ability of DPAH was also compared with that of bis(diethylamino)aluminum hydride (BEAH). The reagent appears to be stronger than BEAH, but weaker than the parent reagent in reducing strength. DPAH shows a unique reducing characteristics. Thus, the reagent reduces aldehydes, ketones, esters, acid chlorides, epoxides, and nitriles readily. In addition to that, ${\alpha},\;{\beta}$-unsaturated aldehyde is reduced to the saturated alcohol. Quinone are reduced cleanly to the corresponding 1,4-reduction products. The examination for possibility of achieving a partial reduction to aldehydes was also performed. Both primary and tertiary aromatic carboxamides are converted to aldehydes with a limiting amount of DPAH. Finally, disulfides and sulfoxides are readily reduced to thiols and sulfides, respectively.

• Food Science of Animal Resources
• /
• v.29 no.5
• /
• pp.579-589
• /
• 2009

This study was conducted to investigate the effects of heating, fiber type used in solid-phase microextraction (SPME, two phase vs three phase) and storage time on the volatile compounds of porcine M. longissimus dorsi (LD). Volatile compounds were measured using a gas chromatography and mass spectrometry (GC/MS) with a quadrupole mass analyzer. Among the volatile compounds identified, aldehydes (49.33%), alcohols (24.63%) and ketones (9.85%) were higher in pre-heated loins ($100^{\circ}C$/30 min), whereas, alcohols (34.33%), hydrocarbons (22.84%) and ketones (16.88%) were higher in non-heated loins. Heating of loins induced the formation of various volatile compounds such as aldehydes (hexanal) and alcohols. The total contents of hydrocarbons, alcohols, and carboxylic acids were higher in two phase fibers, whereas those of esters tended to be higher in three-phase fibers (p<0.05). Most volatile compounds increased (p<0.05) with increased storage time. Thus, the analysis of volatile compounds were affected by the fiber type, while heating and refrigerated storage of pork M. longissimus dorsi increased the volatile compounds derived from lipid oxidation and amino acid catabolism, respectively.

• Journal of Korean Society for Atmospheric Environment
• /
• v.27 no.1
• /
• pp.97-116
• /
• 2011

This study analyzed indoor air pollutants from elementary school with different environment. Air sampling and measurement were carried out from classrooms and hallways from three target elementary schools in the fall and winter seasons. The winter average concentrations of $PM_{10}$, $CO_2$, CO, aldehydes and ketones, and benzene were higher than the fall ones. The fall average concentrations of $O_3$ and $NO_2$ were higher than the winter ones. The concentrations of $PM_{10}$ and $CO_2$ at the schools near the heavy traffic areas and having poor ventilation were higher than those from the other elementary school. The average concentration of CO at the school having heavy traffic volume was highest. The concentrations of $O_3$, $NO_2$, aldehydes and ketones, and VOCs at the school near the shipbuilding industries were highest among the three elementary schools.

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

• Journal of the Korean Society of Tobacco Science
• /
• v.25 no.1
• /
• pp.39-46
• /
• 2003

The essential oils from Burley 21 tobacco was isolated by using the SDE (Simultaneous Distillation & Extraction) apparatus coupled with gas chromatography and mass spectrometry analysis. Burley 21 tobaccos were divided and collected by six stages at intervals of five days during air-curing process. Air curing was conducted with horizontal hanging method in greenhouse settled by shading materials. 55 components were identified by comparisons of retention indices and mass spectral data, including 22 hydrocarbons, 6 alcohols, 3 aldehydes, 9 ketones and 15 miscellaneous compounds. Neophytadiene was the major components of the oils and almost all hydrocarbons were gradually decreased during air-curing process. Most of alcohols were also diminished, on the contrary, 1-pentanol and benzyl alcohol among them were increased. Aldehydes and ketones were increased during air-curing and especially, the concentrations of solanone, $\beta$-damascone, $\beta$-damascenone and megastigmatrienones were much increased. Indole level of miscellaneous compounds were continuously increased during air-curing of Burley 21 tobacco.

• The Korean Journal of Food And Nutrition
• /
• v.29 no.2
• /
• pp.153-161
• /
• 2016

This study investigated the chemical composition of Solidago virga-aurea var. asiatica Nakai essential oils collected using different extraction methods. The essential oils obtained by simultaneous steam distillation extraction (SDE) and hydrodistillation extraction (HDE) methods from the aerial parts of Solidago virga-aurea var. asiatica Nakai were analyzed by GC and GC-MS. Ninety-nine volatile flavor compounds were identified in the essential oil produced from Solidago virga-aurea var. asiatica Nakai using the SDE method. These compounds were classified into eight categories in terms of chemical functionality: 26 hydrocarbons, 8 aldehydes, 36 alcohols, 7 ketones, 12 esters, 5 oxides and epixides, 4 acids, and a miscellaneous one. Spathulenol (15.66%) was the most abundant compound. Ninety-eight compounds including of 35 hydrocarbons, 6 aldehydes, 29 alcohols, 6 ketones, 10 esters, 4 oxides and epixides, 7 acids, and a miscellaneous one were identified in the essential oil from the plant using the HDE method. Hexadecanoic acid (24.74%) was the most abundant compound. The chemical composition of Solidago virga-aurea var. asiatica Nakai essential oils extracted by SDE and HDE methods are characterized by high content of sesquiterpene alcohols and acids, respectively. The extraction methods may be influenced in the chemical composition of natural plant essential oils.

• Journal of the Korean Society of Food Science and Nutrition
• /
• v.21 no.6
• /
• pp.719-724
• /
• 1992

Volatile components in Korean salt-fermented anchovy were analyzed by simultaneous steam distillation-solvent extraction/gas chromatography/mass spectrometry. Seventy-three volatile compounds were detected in sample. Among these, 58 compounds were positively identified and were composed mainly of aldehydes, ketones, alcohols, nitrogen-containing compounds, esters, sulfur-containing compounds, furans and miscellaneous compounds. The amounts of aldehydes was the highest in flavor compounds detected in sample and next followed by alcohols, furans, esters and ketones. In particular, the following high ratios were observed : 3-methylbutanal, 1-penten-3-ol, ehtylacetate, 2-ethylfuran.

• Journal of the Korean Society of Food Culture
• /
• v.36 no.3
• /
• pp.317-324
• /
• 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 the Korean Society of Food Science and Nutrition
• /
• v.43 no.12
• /
• pp.1871-1880
• /
• 2014

Headspace volatile compounds of leaf, stem, and root of Peucedanum japonicum Thunberg (PJT) harvested in March and July were isolated, separated, and identified by using a combined system of solid phase microextraction and gas chromatography/mass spectrometry. Identified numbers of volatile compounds were 72, 75, and 63 in March PJT as well as 78, 73, and 69 in July, respectively. Total compounds identified from PJT consisted of alcohols (1~7), aldehydes (7~15), esters (1~4), hydrocarbons (5~9), ketones (1~2), monoterpenes (13~16), monoterpene alcohols (1~5), monoterpene aldehydes (2~4), monoterpene esters (1~4), monoterpene ketones (1~2), sesquiterpenes (16~24), and miscellaneous compounds (2~3). Major volatile compounds of PJT were monoterpenes at all harvest times and in all parts of PJT. The amounts of ${\beta}$-pinene in leaf and stem harvested in March were highest in monoterpenes, followed by ${\alpha}$-pinene and ${\beta}$-myrcene. However, amounts of volatile compounds of monoterpenes in leaf and stem from July PJT were in the decreasing order of ${\beta}$-pinene, ${\beta}$-phellandrene, and ${\beta}$-myrcene. Of the 39 sesquiterpenes identified in PJT, (E)-caryophyllene in March leaf was the most abundant volatile compound, followed by acoradiene in March leaf, ${\beta}$-elemene, and ${\alpha}$-copaene in July stem.

• Food Science and Preservation
• /
• v.13 no.1
• /
• pp.108-114
• /
• 2006

This study was conducted to determine the volatile flavor compositions of the essential oil and the headspace of Capsella bursa-pastoris Medicus. Essential oil and headspace from the plant were extracted by simultaneous steam distillation extraction (SDE), and solid-phase microextraction(SPME) methods, respectively. Seventy-two compounds including 28 hydrocarbons, 4 aldehydes, 6 ketones, 16 alcohols, 4 esters, 8 acids, and 6 miscellaneous ones were identified in the leaf essential oil extracted by SDE method Sixty-eight compounds including 26 hydrocarbons, 2 aldehydes, 6 ketones, 17 alcohols, 4 esters, 6 acids, and 7 miscellaneous ones were identified in the root essential oil. According to the instrumental analyses the essential oil, phytol ($21.12\%$ in leaves, $20.94\%$ in roots) was the most abundant compound Alcohols, esters, and acids were main groups of the essential oil. On the other hand, thirty-eight compounds including 18 hydrocarbons, 3 aldehydes, 3 ketones, 9 alcohols, 2 esters, 3 miscellaneous ones were identified in the leaf headspace by SPME. In root headspace, thirty-three compounds including 16 hydrocarbons, 2 aldehydes, 1 ketone, 9 alcohols, 3 esten;, and 2 miscellaneous ones were identified. Hydrocarbons($44.02\%$ in leaves, $56.98\%$ in roots) were the main components of the headspace of Capsella bursa-pastoris Medicus.