• Journal of the Korean Society of Food Science and Nutrition
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• v.24 no.6
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• pp.925-931
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• 1995

Volatile compounds in Cheddar, Emmentaler, Parmesan and Roquefort cheese and cheese aroma were concentrated using a microsteam distillation-extraction apparatus and those compounds were analyzed with GC. The lipase-treated cheese aroma concentrates showed significantly higher level of short-chain free fatty acids than natural ripened cheese. The sensory properties of rancidity was high in Emmemtaler and Parmesan. Acidity and fruitness were shown high score in Roquefort. Correlation of free fatty acids and cheese flavor 'sharpness, rancidity and soapy' appear to be related(r=0.8239, 0.8918 and 0.7503), respectively. Methyl ketones, the most striking flavor components of Roquefort cheese showed high amounts in the series 2-heptanone > 2-nonanone > 2-pentanone > 2-undecanone. And the intensity of the Roquefort taste sensation 'acidity and fruitness' is linearly correlated with the methyl ketone concentrations(r=0.9284, r=0.9659).

• Korean Journal of Food Science and Technology
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• v.32 no.5
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• pp.997-1001
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• 2000

The organic acids in 3 kinds of medicinal herbal extracts were screened and compared each other according to their organic acid contents by an efficient gas chromatographic method. It involves solid-phase extraction of organic acids using Chromosorb P with subsequent conversion to stable tert-butyldimethysilyl derivatives for the direct analysis by capillary column gas chromatography and gas chromatography-mass spectrometry. Total of 24 organic acids were reproducibly identified from 3 kinds of herbal extracts. When the GC profiles were simplified to their retention index spectra, characteristic patterns were obtained for each herb sample. As expected, three kinds of herbal extracts showed three distinct patterns.

• Clinical Nutrition Research
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• v.11 no.4
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• pp.241-254
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• 2022

Polycystic ovary syndrome (PCOS) is a heterogeneous clinical syndrome. Recent studies examine different strategies to modulate its related complications. Chlorogenic acid, as a bioactive component of green coffee (GC), is known to have great health benefits. The present study aimed to determine the effect of GC on lipid profile, glycemic indices, and inflammatory biomarkers. Forty-four PCOS patients were enrolled in this randomized clinical trial of whom 34 have completed the study protocol. The intervention group (n = 17) received 400 mg of GC supplements, while the placebo group (n = 17) received the same amount of starch for six weeks. Then, glycemic indices, lipid profiles, and inflammatory parameters were measured. After the intervention period, no significant difference was shown in fasting blood sugar, insulin level, Homeostasis model assessment of insulin resistance index, low-density lipoprotein, high-density lipoprotein, Interleukin 6 or 10 between supplementation and placebo groups. However, cholesterol and triglyceride serum levels decreased significantly in the intervention group (p < 0.05). This research confirmed that GC supplements might improve some lipid profiles in women with PCOS. However, more detailed studies with larger sample sizes are required to prove the effectiveness of this supplement.

• The Bulletin of The Korean Astronomical Society
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• v.35 no.1
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• pp.55.2-55.2
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• 2010

We present a photometric and spectroscopic study of the globular clusters (GCs) in the giant elliptical galaxy NGC 4636 in the Virgo cluster. The photometry of the GCs is based on HST/WFPC2 images for the inner region and deep, wide field Washington $CT_1$ CCD images for the outer region. We investigated the color distribution, the radial number density profile, the spatial distribution, and the mean color of the bright blue GCs about the GCs in NGC 4636. We obtained spectra of the GC candidates in NGC 4636 using the Multi-Object Spectroscopy (MOS) mode of Faint Object Camera and Spectrograph (FOCAS) on the SUBARU 8.2m Telescope. We measured the velocities for 105 GCs in NGC 4636. Using the 238 GCs obtained from combining our results with data in the literature, we investigated the kinematics of the GC system of NGC 4636: the rotation, the velocity dispersion, the radial variation, and the orbit. We also investigated the distribution and the radial variation of the metallicities, ages, and alpha-elements of the GCs in NGC 4636 derived using the absorption lines. We compared the GC kinematics of NGC 4636 with those of other six gEs, finding that the kinematic properties of the GCs are diverse among gEs. We found several correlations between the kinematics of the GCs and the global parameters of their host galaxies. Finally we discuss the implication of the results for the formation models of the GC system in gEs, and suggest a mixture scenario for the origin of the GCs in gEs.

• The Bulletin of The Korean Astronomical Society
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• v.46 no.1
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• pp.52.2-52.2
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• 2021

The Black Eye Galaxy M64 is an intriguing spiral galaxy with a Type III disk break. To trace the origin of its Type III component, we present HST/ACS F606W/F814W photometry of resolved stars in the outer disk of M64 (2.5' < R < 6.5'). First, we discover a bright extended globular cluster (GC) M64-GC1 at R ~ 5.5', and find that it is an old metal-poor halo GC ([Fe/H] = -1.5 +/- 0.2). Second, we find that there are two distinct subpopulations of red giant branch stars (RGBs). One is an old metal-rich ([Fe/H] ~ -0.4) disk population, and the other is an old metal-poor halo population similar to the resolved stars in M64-GC1. The radial number density profile of the metal-rich RGB follows an exponential disk law, while that of the metal-poor RGB follows a de Vaucouleurs's low. From these results, we conclude that the origin of the Type III component in M64 is a halo, not a disk or a bulge. We will further discuss the results in regards to the formation and evolution of M64.

• Korean Journal of Food Science and Technology
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• v.26 no.2
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• pp.162-166
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• 1994

A rapid gas chromatographic (GC) profiling method for the simultaneous analysis of volatile and nonvolatile organic acids was applied to alcoholic beverages (white wine, red wine, brandy, and beer). It involves the solid-phase extraction of organic acids using Chromosorb P as the sorbent and diethyl ether as the eluent with subsequent triethylamine treatment. The resulting triethylammonium salts of acids were directly converted to volatile tert.-butyldimethylsilyl derivatives, which were analyzed by dual-capillary column GC and GC-mass spectrometry. From the alcoholic beverages studied, more than 29 organic acids were detected. When the simplified retention infer (RI) spectra of organic acids, and the direct comparisor method between alcoholic beverages and a test sample were attempted to identify a test sample, it was quickly recognized to be a red wine with the 998 ppt match quality value.

• Analytical Science and Technology
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• v.13 no.1
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• pp.108-120
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• 2000

To perform an effective screening for toxic materials of forensic interest detected in high profile criminal case in biological and environmental samples, we tried to construct a searchable computerized database using HPTLC(High Performance Thin Layer Chromatography) and GC/MS. Retardation factor($R_f$) values and UV spectral data of HPTLC were investigated for 160 pesticides, 34 chemicals and 39 explosives of standard grade. The data were compiled in a library. We also analyzed 112 pesticides, 31 chemicals and 17 explosives and 57 volatile organic compounds(VOCs) by GC/MS. The data for RT and characteristic mass ions were also compiled in a library.

• Journal of Korean Society for Atmospheric Environment
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• v.21 no.3
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• pp.315-327
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• 2005

The total of 35 target VOCs (volatile organic compounds), which were included in the TO-14, was selected to develop a VOCs' source profile matrix of the Yeosu Petrochemical Complex and to test its collinearity by singular value decomposition(SVD) technique. The VOCs collected in canisters were sampled from 12 different sources such as 8 direct emission sources (refinery, painting, wastewater treatment plant, incinerator, petrochemical processing, oil storage, fertilizer plant, and iron mill) and 4 general area sources (gasoline vapor emission, graphic art activity, vehicle emission, and asphalt paving activity) in this study area, and then those samples were analyzed by GC/MS. Initially the resulting raw data for each profile were scaled and normalized through several data treatment steps, and then specific VOCs showing major weight fractions were intensively reviewed and compared by introducing many other related studies. Next, all of the source profiles were tested in terms of degree of collinearity by SVD technique. The study finally could provide a proper VOCs' source profile in the study area, which can give opportunities to apply various receptor models properly including chemical mass balance (CMB).

• Asian-Australasian Journal of Animal Sciences
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• v.27 no.4
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• pp.551-560
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• 2014

Twenty-four male 1-year old swamp buffaloes (Bubalus bubalis) were randomly allocated to 4 groups. One group grazed on guinea grass (GG) and another on guinea grass and the legume Stylosanthes guianensis (GL). The other two groups were kept in pens and fed freshly cut guinea grass and concentrate at an amount of 1.5% (GC1.5) and 2.0% (GC2.0) of body weight, respectively. The effect of the different feeding intensities on carcass characteristics and meat quality were assessed. The mean body weight at slaughter was 398 (${\pm}16$) kg. Average daily gain was higher in concentrate-supplemented groups (570 and 540 g/d in GC1.5 and GC2.0, respectively) when compared to GG (316 g/d) and GL (354 g/d) (p<0.01). Likewise, the warm carcass weight was higher in GC1.5 and GC2.0 compared to GG and GL. Dressing percentage was 48.1% and 49.5% in GC1.5 and GC2.0 in comparison to 42.9% and 44.8% observed in GG and GL, respectively. Meat of Longissimus throracis from GC1.5 and GC2.0 was redder in color (p<0.01), while water holding capacity (drip and thawing loss) was improved in pasture-fed groups (p<0.05). Protein and fat content of Longissimus thoracis was higher in animals supplemented with concentrate (p<0.01), as was cholesterol content (p<0.05), whereas PUFA:SFA ratio was higher and n-6/n-3 ratio lower (p<0.01) in pasture-fed buffaloes. Results of the present study showed that the supplementation of pasture with concentrate enhances the growth and carcass characteristics of swamp buffaloes expressed in superior dressing percentage, better muscling, and redder meat with a higher content of protein and fat, whereas animals grazing only on pasture had a more favorable fatty acid profile and water holding capacity. In conclusion, the supplementation of concentrate at a rate of about 1.5% of body weight is recommended to improve the performance and carcass quality of buffaloes.

• Korean Journal of Plant Resources
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• v.26 no.6
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• pp.718-725
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• 2013

Components extracted from 7 species and 18 populations of Chrysosplenium in Korea were compared and analyzed using GC-MS analysis. 57 components (${\geq}80%$ quality) were identified, of which neophytadiene, palmitic acid and phytol were found at all the taxa. Percentage composition of isolated extracts showed a clear difference in components type and GC-MS profile. On the basis of that result, data matrix was made and cluster analysis using UPGMA was conducted. From the result of cluster analysis, two groups were recombined; one with alternate leaves comprised C. japonicum in Ser. Alternifolia and C. flagelliferum in Ser. Flagellifera and the other with opposite leaves gradationally comprised C. psuedofauriei in Ser. Sinica, C. ramosum in Ser. Oppositifolia and C. sphaerospermum, C. valdepilosum, C. flaviflorum in Ser. Pilosa. These chemotaxonomic results agreed in general with those of existing studies on external morphology and molecular. In conclusion, chemical composition can be an useful characters in understanding the relation analysis among interspecific and intraspecific complex with the help of cluster analysis of 7 species and 18 populations of Chrysosplenium in Korea.