• Journal of Life Science
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• v.17 no.2 s.82
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• pp.286-292
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• 2007

Free amino acids and volatile compounds of fresh garlic and its liqueur were investigated to search elution profile of those components as basic data for development of garlic liqueur. The garlic was soaked in 20% alcohol solution and then sampled every week for 5 weeks. The major free amino acids were L-aspartic acid, L-glutamic acid, L-arginine, L-alanine, L-proline, L-asparagine and L-serine. Neutral amino acids such as L-threonine, L-proline, L-valine and L-leucine, and aromatic amino acids such as tyrosine and phenylalanine were eluted over 80% of those content in fresh garlic after 3 weeks of soaking, but acidic, basic and sulfur containing amino acids were below 80% even after 5 weeks. Sulfide compounds such as diallyl trisulfide, diallyl disulfide, methyl allyl disulfide, 2-vinyl-4H-1,3-dithi in, 3-vinyl-3,4-dihydro-1,2-dithiin, 3,5-diethyl-1,24-trithiolane, isobutyl isothiocyanate and diallyl sulfide were identified as major volatile compounds of fresh garlic by using GC/MS. Among volatile compounds of fresh garlic, allyl alcohol, diallyl disulfide, 3,5-diethyl-1,2,4-trithiolane, diallyl trisulfide and 3,4-dimethoxy furan were eluted to liqueur, but those compounds except 3,5-diethyl-1,2,4-trithiolane were lowered in liqueur during soaking. Furfural, 5-methylfurfural, 5-hydroxymethylfurfural, dimethyl pyrazine, furfuryl alcohol, 3-hydroxy-2-bytanone and 2,3-dihydro-3,5-dihydroxy-6-methyl-4H-pyr-an-4-one were generated newly and their content increased in liqueur during soaking.

• Journal of Life Science
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• v.16 no.2 s.75
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• pp.323-327
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• 2006

The Formation of acrylamide was studied in Maillard model reaction systems based on asparagine-glucose. The mixture of asparagine and glucose in equal molar ratio, and then heated at 125, 150, 175 and $200^{\circ}C$ for 10, 20 and 30 minute, respectively. The reaction products were extracted with ethyl acetate and methanol, and then isolated and detected on FFAP capillary column and HP-5MS 5% phenyl methyl siloxane column by using GC/MS. Acrylamide was detected only from methanol extracts and on FFAP capillary column, at retention time 23.53 min., and the detection limit was 4.6 ng. Acrylamide content mainly increased with increasing temperature and processing time till $175^{\circ}C$, therefore, maximal acrylamide formation occurred at $175^{\circ}C$ for 10 minute ($116{\mu}g/g$), while, above $175^{\circ}C$, higher temperatures or prolonged processing times caused a decrease of acrylamide levels, finally disappeared at $200^{\circ}C$ for 30 minute. Three major compounds were identified as 1,3-dihydroxypropanone, 2,3-dihydro-3,5-dihydroxy-6-methyl-4H-pyrane-4-one and 5-hydroxymethylfurfural, and three minor compounds also as 5-methylfurfural, 2-acetylpyrrole and N,N-dimethylcyclohexamine, from ethyl acetate or methanol extracts on FFAP or HP-5MS capillary column.

• Journal of the Korean Wood Science and Technology
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• v.37 no.6
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• pp.578-584
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• 2009

We investigated acid hydrolysis characteristics of yellow poplar woodmeal with concentrated sulfuric acid for high concentration of monosaccharides production. Woodmeal to 72% sulfuric acid ratio (w/w), $2^{nd}$ hydrolysis temperature and time were main variables for finding optimum reaction condition. Optimum woodmeal to 72% sulfuric acid ratio was 1 : 2.61 (w/w) and $2^{nd}$ hydrolysis temperature and time was $105^{\circ}C$ and 40 min as 44.8 g/L of glucose and 25.2 g/L of xylose in hydrolysis solution. In this acid hydrolysis solution, furfural, 5-HMF, low molecular weight phenolic compounds were identified. Furfural and 5-HMF concentration were increased as increasing $2^{nd}$ hydrolysis time. More than 40 min of $2^{nd}$ hydrolysis at $110^{\circ}C$, xylose concentration was decreased but glucose concentration was leveled out because xylose to furfural reaction was faster than xylan to xylose, but cellulose to glucose reaction was similar rate with glucose to 5-HMF at that $2^{nd}$ hydrolysis reaction condition.

• Journal of the Korean Society of Food Science and Nutrition
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• v.35 no.7
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• pp.881-885
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• 2006

The product formation and changes in color of glucose/glutamine model system were investigated in relation to heating temperature and time. The mixtures of glucose and glutamine in equal molar ratio were heated at 125, 150 and $175^{\circ}C$ for 10, 20 and 30 minute, respectively. Acetic acid, butanoic acid, 2-butenoic acid, di-(2-cthylhexyl)phthalate, 2,3-dihydro-3,5-dihydroxy-6-methly-4H-pyran-4-one and 5-hydroxymethylfurfural were identified as a major compounds, and 1,3-dimethylbenzene, 2-ethylhexanol, furfural, 5-methylfurfural, 2-pyrrolidinone, and 2,6-di(t-butyl)-4-hydroxy-4-methyl-2.5-cyclohexadien-1-one as 6 minor compounds by using GC/MS. The contents of acetic acid, 2-ehylhexanol and 2-pyrrolidinone increased with increased heating temperature and time, whereas the formation of the other 9 compounds increased up th heating conditions of $150^{\circ}C$ for 10 or 20 min or $175^{\circ}C$ for 10 min, and decreased dramatically with heating above those conditions. Color parameter $L^*$ decreased with increasing heating conition, resulting in dark brown color in final products. Changes of redness parameter $a^*$ and yellowness $b^*$ showed similar to those of the contents of 9 compounds mentioned as above.

• Archives of Pharmacal Research
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• v.27 no.9
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• pp.912-914
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• 2004

Seven compounds were isolated from the stem of Acanthopanax senticosus by repeated col-umn chromatography. Their structures were elucidated as isovanillin (1), (-)-sesamin (2), iso-fraxidin (3), (＋)-syringaresinol (4), 5-hydroxymethylfurfural (5), eleutheroside B (6), and eleuth-eroside E (7) by spectral analysis. Among them, isovanillin (1) was isolated for the first time from the family Araliaceae.

• Journal of the Korean Wood Science and Technology
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• v.50 no.6
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• pp.475-489
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• 2022

The objective of this study was to understand the conversion characteristics of glucose and xylose using the major monosaccharide standards for lignocellulosic biomass. The acid-catalyzed organosolv pretreatment conducted using ethanol was significantly different from the acid-catalyzed process conducted in an aqueous medium. 5-hydroxymethylfurfural (5-HMF), levulinic acid and furfural were produced from glucose conversion. The maximum yield of 5-HMF was 5.5%, at 200℃, when 0.5% sulfuric acid was used. The maximum yield of levulinic acid was 21.5%, at 220℃, when 1.0% sulfuric acid was used. Furfural was produced from xylose conversion and under 0.5% sulfuric acid, furfural reached the maximum yield 48.5% at 210℃. Ethyl levulinate and methyl levulinate were also formed from the glucose standard following the esterification reaction conducted under conditions of the combined conversion method, which proceeded under both ethanol-rich and water-rich conditions.

• Journal of Applied Biological Chemistry
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• v.56 no.3
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• pp.131-135
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• 2013

Jaeumganghwa-tang (JGT) is a traditional herbal medicine used for chronic bronchitis and inflammatory diseases. The variation in the amount of bioactive components of JGT and its fermentation JGT with ten species of microorganism was investigated via high performance liquid chromatography coupled with diode array detection (HPLC-DAD). Simultaneous qualitative and quantitative analysis of eight bioactive compounds; 5- hydroxymethylfurfural (5-HMF), paeoniflorin, nodakenin, hesperidin, nodakenetin, palmatine, berberine and glycyrrhizin were achieved by comparing their retention times ($t_R$) and UV spectra with those of the standard compounds. In the result, the paeoniflorin amount was 6.95 mg/g that as a main compound in JGT. The amount of nodakenetin was the highest in the fermented-JGT with Lactobacillus fermentum KFRI 145 ($0.47{\pm}0.01mg/g$), which was increased by 2,250% compared to that in non-fermented JGT ($0.02{\pm}0.00mg/g$). In the fermented JGT using Lactobacillus acidophilus KFRI 162, most components were increased than non-fermented JGT, except paeoniflorin and hesperidin.

• Bulletin of the Korean Chemical Society
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• v.31 no.2
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• pp.511-514
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• 2010

• YAKHAK HOEJI
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• v.29 no.1
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• pp.32-38
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• 1985

The anthelmintic substance of the roasted fruits of Prunas mume against Clonorchis sinensis was isolated and its structure was identified by chemical and physical methods. The results obtained from the experiments are as follows: 1) The methanol extract of the roasted fruits of P. mume was fractionated into four parts: petroleum ether, ethyl ether, ethyl acetate and water soluble part. Among these, etherial fraction was found to have strong wormicidal effect on liberated metacercaria of Clonorchis sinensis. 2) From the etherial fraction, the wormicidal substance was isolated by silica gel, polyamide and sephadex column chromatography and identified to be 5-hydroxymethylfurfural (5-HMF) by chemical and spectral data. 3) 5-HMF was synthesized and administered to the rabbits infected with C. sinensis. On the 2nd day after administration, the EPG (eggs per gram in feces) reached to the maximal value. Among the adult worms isolated from the bile duct of the treated animal, 84% of worms were damaged morphologically. 4) The content of 5-HMF in the fruits of P. mume which were roasted in an oven at $90-110^{\circ}C$ for 52 hours and that in the fresh fruits was evaluated by HPLC. The content of 5-HMF was 0.8% in the roasted fruits and 0.02% in the fresh ones.

• Journal of the Korean Society of Food Science and Nutrition
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• v.40 no.1
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• pp.84-88
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• 2011

Some thermally processed foods have higher biological activities due to their various chemical changes during heat treatment. Especially, 5-hydroxymethylfurfural (HMF) is derived from dehydration of sugars and has been identified in processed garlic. The biological function of HMF have revealed as antisickling agent and thyrosinase inhibitor. This study was carried out to examine the formation of HMF and free sugars from the aged garlics when it is treated at 60 and $75^{\circ}C$ and different incubation periods from 7 to 35 days. HMF and free sugars from the hot-water extracts of aged garlics were analyzed with GC/MS, LC/MS, and HPLC. The amount of HMF was higher than at $75^{\circ}C$ and increasing incubation period. Among free sugars, the only fructose except glucose and sucrose was formed and converted to HMF at high temperature and long incubation period. However, fructose formed in low temperature during making of aged garlic was rarely converted to HMF. This result indicates that formation of HMF can be dependent on the temperature and incubation period for making aged garlic.