• Journal of the Korean Society of Food Science and Nutrition
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• v.29 no.6
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• pp.1042-1049
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• 2000

Irradiation-induced volatile flavor compounds in irradiated (1, 3, 5, 10 kGy) beef were analyzed by liquid liquid continuous extraction (LLCE) and gas chromatography/mass spectrometry (GC/MS) methods. One hundred fifty volatile compounds were detected in irradiated beef. These compounds were composed mainly of 71 hydrocarbons, 35 aromatic compounds, 15 aldehydes, 7 ketones, 4 acids, 6 esters and 12 miscellaneous compounds. Among these, only 6 volatile compounds including (E) -2-hexenal, nonene, 2-nonenal, cyclodecene, dodecene and cyclododecene were detected as irradiation-induced volatile flavor compounds, comparing with unirradiated beef meat. However, 4 volatile compounds, such as cyclodecene (r=0.88), (E)-2-hexenal (r=0.85), nonene (r=0.74) and 2-nonenal (r=0.70), having a positive correlation coefficient with the increment of irradiation dose, were considered as marker compounds for detecting irradiation dosages in irradiated beef.

• The Korean Journal of Pesticide Science
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• v.18 no.3
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• pp.141-147
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• 2014

Fenpyroximate is acaricide of pyrazole group. This acaricide have already been permitted for herb cultivation. This experiment was conducted to establish a determination method for fenpyroximate residue in herbal medicines using HPLC-PDA and HPLC-MS/MS. Fenpyroximate residue was extracted with acetone from samples of herbal which Liquorice Root (Glycyrrhiza uralensis) and Safflower Seed (Carthamus tinctorius Linne). The extract was diluted with saturated saline water and dichloromethane liquid-liquid partition (extraction) was followed to recover fenpyroximate from the aqueous phase. Amino propyl ($NH_2$) and florisil column chromatography was additionally employed for final clean up of the extract. The fenpyroximate was quantitated by HPLC-PDA and HPLC-MS/MS. The herbals were fortified with fenpyroximate at 2 or 3 levels per crop. Mean recovery ratio were ranged from 72.0 to 106.4%. The coefficients of variation were ranged from 0.2 to 4.4. Therefore, this analytical method was reproducible and sensitive enough to determine the residue of fenpyroximate in herbal medicines.

• Korean Journal of Food Science and Technology
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• v.29 no.3
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• pp.417-426
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• 1997

Rice bran protein hydrolysates were prepared and some of their physicochemical properties were investigated to utilize rice bran as starting material for functional food ingredient. Rice bran proteins (RBP) were prepared from defatted rice bran by alkaline extraction and isoelectric precipitation. The enzyme for hydrolysis of RBP was selected through measuring relative activity by pH-drop method and comparing the degree of hydrolysis (DH) of hydrolysates. The enzymatic hydrolysates prepared by $Esperase^{\circledR}$ treatment were partitioned into two fractions by ultrafiltration(UF) with a 10 kDa molecular weight cut-off membrane. Each fraction was applied to a cholic acid-conjugated ${\omega}-aminohexyl$ Sepharose 4B column and the bile acid-binding components were obtained by eluting with deoxycholate. Gel permeation chromatography on a Sephadex G-50 column revealed that molecular weight of the bile acid-binding fraction of UF permeate was distributed in ranges of $2\;kDa{\sim}10\;kDa$ and $0.2\;kDa{\sim}0.6\;kDa$. Three peaks (R-1, R-2 and R-3) were obtained by prep-HPLC of bile acid-binding fraction of UF retentate and analyzed for total and free amino acid composition. The results showed that proline content of the bile-acid binding polypeptides and peptides was four times as much as that of rice bran protein and that the peak corresponding to higher average hydrophobicity had a higher free amino acid content. Average hydrophobicity slightly increased with enzymatic hydrolysis.

• Maxillofacial Plastic and Reconstructive Surgery
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• v.19 no.3
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• pp.265-286
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• 1997

Bone morphogenetic proteins(BMPs) are a group of transforming growth factor beta(TGF-${\beta}$)-related factors and multifunctional proteins, especially the only known biologic factors capable of inducing endochondral bone formation at an extraskeletal site. This study was performed to investigate the effect of the partially purified porcine BMP(pBMP) at an ectopic site. PBMP was partially purified from porcine bone matrix and its activity was monitored by an in vivo bioassay. The purification method utilized extraction of the bone-inducing activity with 4M guanidine, followed by chromatography on heparin-Sepharose. Active fractions were assayed by sodium dodecyl sulfate-polyacrylamide gel electrophoresis. And the fractions were reconstituted with inactive insoluble collagenous bone matrix from rats, acid soluble type I collagen from rat tail and chondroitin-6-sulfate sodium salt and implanted into the pectroralis muscle pouches of Sprague-Dawley rats. And the carrier complex was implanted on the opposite side as control. The rats were sacrificed at the day of 1st, 3rd, 5th, 7th, 11th, 14th and 21st after implantation and examined histologically, radiologically and biochemically. And alkaline phosphatase activity and calcium content were used as indices of bone formation. The results were as follows ; 1. Active fractions were localized in a zone between 31 and 40 KDa on SDS-PAGE. 2. The implanted 3.0mg of the partially purified pBMP induced cartilage and bone in the muscle tissue of rats through an endochondral ossification process. 3. Inactive insoluble bone matrix, type I collagen and chondroitin-6-sulfate have functioned as carriers for pBMP, but revealed some foreign body reactions. 4. Soft X-ray didn't reveal significant change between the experimental and the control group. 5. The alkaline phosphatase activities in the experimental group of 5th, 7th, 11th, 14th and 21st were increased significantly compared with control (p<0.01) with the peak in the group of 11th day. 6. With time, the calcium content of the experimental group increased. And the calcium contents in the experimental group of 11th, 14th and 21st were increased significantly compared with control (p<0.01).

• Journal of the Korean Society of Food Science and Nutrition
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• v.30 no.6
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• pp.1033-1037
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• 2001

Garlic oleoresins were made by extracting with four solvents of methanol, methyl acetate hexane and acetone from chopped garlic, respectively, and the volatile compounds of each extract were separated by gas chromatography installed with polar (supelcowax-10$^{TM}$) and nonpolar (HP-5) capillary columns, respectively, and identified by matching mass data of mass selective detector and Kovat\`s retention index with references. The numbers of the volatile compounds identified the garlic oleoresin by polar and nonpolar columns from in garlic oleoresins were 41 and 32, respectively. In polar column, 13 pyrans, 11 sulfur-containing compounds 6 furans 2 alcohols and 2 heterocyclic compounds were identified. In nonpolar column, 11 sulfur-containing compounds 5 acids 3 furans and eugenol were identified. The major sulfur-containing compounds identified from the oleoresins were 3, 3'-thiobis-1-propene, methyl 2-propenyl disulfide, dimethyl trisulfide, di-2-prnpenyl-trisulfide, 2-thiophenecarboxylic acid. The amount of these sulfur-containing compounds isolated from the oleresins were more abundant in polar column than in nonpolar column. The most efficient solvent for extracting volatile compounds of garlic was methanol but the most useful solvent for extracting sulfur-containing compounds was methyl acetate of less polarity.y.

• Clean Technology
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• v.18 no.4
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• pp.426-431
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• 2012

Carbon-rich coal can be utilized as a fuel for direct carbon fuel cell (DCFC). However, left-behind ash after the electrochemical oxidation may hinder the electrochemical reactions. In this study, we produced ash-free coal (AFC) by thermal extraction and then tested it as a fuel for DCFC. DCFC was built based on solid oxide electrolyte and the electrochemical performance of AFC mixed with $K_2CO_3$ was compared with AFC only. Significantly enhanced power density was found by catalytic steam gasification of AFC. However, an increase of the power density by catalytic pyrolysis was negligible. This result indicated that a catalyst activated the steam gasification reactions, producing much more $H_2$ and thus increasing the power density, compared to AFC only. Results of a quantitative analysis showed much improved kinetics in AFC with $K_2CO_3$ in agreement with DCFC results. A secondary phase of potassium on yttria-stabilized zirconia (YSZ) surface was observed after the cell operation. This probably caused poor long-term behavior of AFC with $K_2CO_3$. A thin YSZ (30 ${\mu}m$ thick) was found to be higher in the power density than 0.9 mm of YSZ.

• Journal of the Korean Chemical Society
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• v.30 no.4
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• pp.369-376
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• 1986

Diosgenin in an Indonesian Costus speciosus was determined by capillary gas-liquid chromatography (GLC). The experimental conditions for the hydrolysis, extraction and acetylation of the diosgenin, and the determination by GLC were investigated. 0.20g of dried sample powder was refluxed in the solution of 3N HCI and xylene at 95∼100${\circ}C$ for 4 hours and the xylene layer was separated. The residue evaporated the xylene was refluxed in 20 : 80 acetic anhydride-pyridine for 30 minutes and the diosgenin acetate was extracted with diethyl ether. Dehydrated with anhydrous $Na_2SO_4$ and evaporated the ether, the residue was dissolved in 5.00ml of n-hexane and injected into GLC. Capillary column of SE-30 25m ${\times}$ 0. 33mm was installed in GLC and the column temperature was increased from 180${\circ}$ to 270${\circ}C$ at rate of 10${\circ}C$/min. The flow rate of carrier gas $N_2$ was 2ml/min and FID was used to detect. The analytical result of the diosgenin was 0.281% and relative standard deviation of 5 measures was 1.8%.

• Food Science and Preservation
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• v.17 no.6
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• pp.770-776
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• 2010

Sarcodon aspratus (Berk.) S. Ito is a wild mushroom commonly consumed in Korea due to its beneficial effects on health. However, only limited information on the volatile and nonvolatile constituents of S. aspratus is available. In the present study, the total concentration of mushroom soluble sugars, including glucose, trehalose, sucrose, and xylose, was found to be 202.5 mg/kg. The total contents of free and essential amino acids were 2,592.1 mg/kg and 1,249.5 mg/kg, respectively; arginine, lysine, methionine, and valine were the major amino acids present. The contents of total 5'-nucleotides and flavor 5'-nucleotides in S. aspratus were 2,510.7 mg/kg and 773.4 mg/kg, respectively. The volatile components of S. aspratus were collected by simultaneous distillation-extraction (SDE) and analyzed by gas chromatography-massspectrometry (GC-MS). A total of 27 volatile compounds were isolated and identified. The most abundant was l-octen-3-ol, which accounted for more than 68% of total volatiles; other important compounds were 2-octen-1-ol, 1-octen-3-one, and 2-octenol. Our results provide preliminary data for the development of S. aspratus as a food material.

• Food Science and Preservation
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• v.23 no.7
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• pp.977-988
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• 2016

The volatile flavor compounds in five Jeju citrus fruit varieties (Cheonhyehyang, Hallabong, Jinjihyang, Hwanggeum hyang and Redhyang) were extracted by simultaneous distillation-extraction (SDE) using solvent mixture of n-pentane and diethyl ether (1:1, v/v) and analyzed by using gas chromatography-mass spectrometry (GC-MS). The number of aroma compounds were identified with : 104 (4,939.77 mg/kg) in Cheonhyehyang, 98 (3,286.38 mg/kg) in Hallabong, 105 (3,317.56 mg/kg) in Jinjihyang, 102 (4,293.39 mg/kg) in Hwanggeumhyang, and 108 (4,049.94 mg/kg) in Redhyang. The detected main volatile compounds were; limonene, sabinene, ${\beta}$-myrcene, ${\alpha}$-pinene, ${\beta}$-pinene, linalool, 4-terpineol, ${\alpha}$-terpineol, (E)-${\beta}$-ocimene and ${\gamma}$-terpinene. Among the identified volatiles compounds, ethyl-benzene, nonanol, 1-p-menthen-9-al, (E)-isocarveol, methyl salicylate, ${\alpha}$-terpinen-7-al, perilla alcohol, and ethyl-dodecanoate were detected in Cheonhyehyang. only Furthermore, ${\beta}$-chamigrene and ${\alpha}$-selinene were in Hallabong only; 3-hydroxybutanal, (E)-2-nonenal, isoborneol, octyl acetate, (E)-2-undecenal, ${\beta}$-ylangene and guaia-6,9-diene in Jinjihyang. ${\rho}$-Cymenene, ${\beta}$-thujone, selina-4,11-diene and (E,E)-2,6-farnesol in Hwanggeumhyang only; and ${\rho}$-cymen-8-ol, bornyl acetate, carvacrol, bicycloelemene, ${\alpha}$-cubebene and 7-epi-${\alpha}$-selinene in Redhyang only. This study confirmed the differences in composition and content of volatile aroma components in five varieties of Jeju citrus fruits.

• Korean Journal of Food Science and Technology
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• v.37 no.4
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• pp.537-541
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• 2005

Estimation of concentrations of PAHs [benzo(a)anthracene, chrysene, benzo(b)fluoranthene, benzo(k)fluoranthene, benzo(a)pyrene, dibenzo(a,h)anthracene, benzo(g,h,i)perylene, indeno(1,2,3-c,d)pyrene] in cereals, pulses, potatoes, and their products available in Korean markets gave mean levels of 0.13, 0.08, 0.06, 0.03, 0.08, 0.15, 0.45, and $0.14{\mu}g/kg$, respectively, with recoveries between 82.6-106.6%. Methodology involved saponification and extraction with n-hexane, purification on Sep-Pak Florisil cartridges, and high performance liquid chromatography using a fluorescence detector.