• KOREAN JOURNAL OF CROP SCIENCE
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• v.57 no.2
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• pp.188-194
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• 2012

This study was carried out to evaluate the quality properties, fatty acid composition and amino acid composition of major Korean inbred lines and hybrids of maize for corn breeding. Protein content of $F_2$ seeds was 9.0%, which was slightly lower than those of inbred lines, 11.4%, and $F_1$ seeds, 10.9%. in hybrid maizes. Lipid content of $F_2$ seeds of hybrid maizes was 4.2%, slightly higher than those of inbred lines, 3.3%, and $F_1$ seeds, 3.6%. However, there was no significant difference in ash content. The amount of linoleic acid in inbred lines, $F_1$ and $F_2$ seeds of hybrid maizes was highest among all fatty acids and followed by oleic acid, palmitic acid, stearic acid and linolenic acid. The composition of saturated fatty acid of $F_2$ seeds was 17.6%, similar to $F_1$ seeds but it was lower than that of inbred lines. The composition of unsaturated fatty acid of $F_2$ seeds was 82.4%, similar to $F_1$ seeds but was higher than inbred lines. The content of leucine of $F_2$ seeds was lower than inbred lines and $F_1$ seeds. The content of valine, serine, threonine, cysteine, aspartic acid, lysine, arginine, histidine of $F_2$ seeds was higher than inbred lines and $F_1$ seeds. MMA (monoamino monocarboxylic acid) in inbred lines, $F_1$ and $F_2$ seeds of hybrid maizes was highest among all amino acids and followed by DMA (diamino monocarboxylic acid) and AAA (aromatic amino acid).

• Journal of the Korean Society of Food Science and Nutrition
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• v.35 no.1
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• pp.7-14
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• 2006

The antioxidative activity and the related parameters of hot water extracts obtained from 16 medicinal plants were tested. The extraction yield was the highest in Salvia miltiorrhiza Bunge $(36.49\%)$ pH range was $4.00\~5.92$ in all samples. Absorbance at 280 nm was examined to determine aromatic compounds content. The absorbance of $250{\mu}g/mL$ sample was the highest in Prunella vulgaris Linne var. lilacina Nakai (2.872) and below 0.5 in Cirsium maackii, Crataegus pinnatifida Bunge and Zizyphus jujuba Miller. Also, absorbance at 420 nm was high in order of Prunella vulgaris Linne vu. lilacina Nakai (1.312), Zea mays Linne (0.917) and Inula japonica Thunberg (0.725) Total phenolic compounds contents was the highest in Prunella vulgaris Linne var. lilacina Nakai $(5.07{\pm}0.05\;mg/100g)$ and flavonoids contents was 2-fold higher in Salvia miltiorrhiza Bunge $(4.82{\pm}1.16\;mg/100g)$ than the other samples. Electron donating abilities of Zizyphus jujuba Miller, Cornus officinalis Siebold et Zuccarini and Salvia miltiorrhiza Bunge were over $90\%$ at $1000{\mu}g/mL$. Reducing power had similar tendency to electron donating ability while reducing power was significantly lower in samples compared to BHT. Two samples (Prunella vulgaris Linne val. lilacina Nakai and Inula japonica Thunberg) were found to have more than $50\%$ nitrite scavenging effect at $500{\mu}g/mL$ while 8 kinds samples (Zizyphus jujuba Miller, Cornus officinalis Siebold 81 Zuccarini, Chrysanthemum indicum Linne, Prunella vulgaris Linne var. lilacina Nakai, Inula japonica Thunberg, Acanthopanax sessiliflorum Seeman, Salvia miltiorrhiza Bunge and Curcuma longa Linne) showed more than $50\%$ nitrite scavenging effect at $1000{\mu}g/mL$. Prunella vulgaris Linne var. lilacina Nakai showed significantly stronger nitrite scavenging effect than other samples, and its activity was $59.62{\pm}1.573\%$ and $80.58{\pm}0.300\%$ at concentrations of 250 and $1000{\mu}g/mL$, respectively.

• Journal of the Korean Applied Science and Technology
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• v.34 no.3
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• pp.555-561
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• 2017

This study was conducted to investigate the several physicochemical extraction characteristics and the antioxidant activities of ethanol extract from Rhus javanica bark. The contents of soluble solid and sugar in extract was measured to 73.5 mg/100g dry basis and $17.8^{\circ}Brix$, respectively. The contents of total aromatics, total flavonoids and total phenolic compounds was measured to 0.508 in absorbance, 49.88 mg/100g and 296.6 mg/100g, respectively. The reducing power of extract was about 27.5 % of ascorbic acid with the same soluble solid contents of the extract. But the ferric reducing antioxidant power and the DPPH radical scavenging ability of extract were measured to equivalent to those of ascorbic acid. The metal ion chelating ability of the extract was 81.58 % whereas that of ascorbic acid was 74.73 %. The nitrite scavenging ability of the extract was measured to 51.76 % at pH 2. And the antioxidative effect of the extract on soybean oil was observed with Rancimat test.

• Journal of the Korean Society of Food Science and Nutrition
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• v.41 no.1
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• pp.116-122
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• 2012

Volatile flavor compounds derived from four black garlic extracts purchased in a local market were analyzed for the purpose of quality assessment. A total of 68 compounds was detected in samples using solid phase microextraction (SPME)/GC/MSD, and they were mainly sulfur-containing compounds, including three unknown compounds (21), aldehydes (10), furans (7), alcohols (6), aromatic compounds (7), ketones (4), acids (4), nitrogen-containing compounds (3), esters (2), and miscellaneous compounds (4). 2,6-Dimethyl-4-heptanone having a fruity-sweet odor was the most abundant in all of the samples. Six sulfur-containing compounds including allyl sulfide, 4-methyl-1,2,4-thiazole, 1,3,5-trithiane, unknown I (RI 1564), unknown II (RI 1565), and unknown III (RI 1613) were detected in all of the samples and appeared to contribute to the garlic-like odor. Particularly, three aldehydes (3-methylbutanal, benzaldehyde, phenylacetaldehyde), four furans (furfural, 2-acetylfuran, 5-methyl-2-furfural, furfural alcohol), and others (2,6-dimethylpyrazine, acetic acid) formed through a Maillard reaction during garlic aging were detected in all of the samples, and they contributed to the characteristic burnt, sweet, and sour flavors of black garlic extracts.

• Korean Journal of Food Science and Technology
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• v.37 no.6
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• pp.866-872
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• 2005

Cocentrations 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 fish (n=120), shellfish(n=50) and their products (n=35) were estimated by saponification and extraction with n-hexane, clean-up on Sep-Pak Florisil Cartridges and HPLC/FLD. Overall recoveries for eight PAHs spiked into samples ranged from 90 to 106%. Mean level of benzo(a)anthracene, chrysene, benzo(b)fluoranthene, benzo(k)fluoranthene, benzo(a)pyrene, dibenzo(a,h)anthracene, benzo(g,h,i)perylene and indeno(1,2,3-c,d)pyrene were not detected, 0.01, 0.04, 0.07, 0.05, 0.004, 0.0008 and 0.06ng/g, respectively, similar to those reported by other countries.

• Journal of the Korean Society of Food Science and Nutrition
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• v.43 no.1
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• pp.102-109
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• 2014

Crab-like flavoring base (CFB) was made from a concentrated snow crab cooker effluent (SCCE) containing five food additives (proline, glycine, arginine, methionine, fructose) using reaction flavor technology (RFT). The volatile flavor compounds in CFB were compared between raw (SCCE) and control (without food additives) samples using solid phase microextraction (SPME) and gas chromatography with mass selective detector. A total of 74 compounds were detected in all samples (30 raw samples, 34 control samples, 55 CFB samples). A total of 22 nitrogen-containing compounds, including 19 pyrazines and 3 pyridines, were formed through RFT and increased 27 times compared to the control. Dimethyl trisulfide and dimethyl disulfide were predominant sulfur-containing compounds that increased through RFT, while aromatic compounds decreased through RFT. Seven compounds, tetramethylpyrazine, 2-ethyl-3,5,6-trimethylpyrazine, 2,3,5-trimethyl-6-(3-methylbutyl)pyrazine, 2-ethyl-3,5-dimethylpyrazine, 2,5-dimethyl-3-(3-methylbutyl)pyrazine, 2-ethyl-3,6-dimethylpyrazine, and 2-decanone potentially have a role in CFB odor by Pearson's correlation analysis.

• Journal of Life Science
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• v.21 no.12
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• pp.1740-1745
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• 2011

Volatile flavor compounds of 3 commercial products of black onion extract (produced in Changnyeong, Muan and Jeungpyeong) purchased in the online/offline markets were analyzed. A total of 51 compounds were detected in samples by solid phase microextraction (SPME)/GC/MSD, consisting mainly of carbonyl compounds (15), sulfur-containing compounds (8), aromatic compounds (6), furans (6), nitrogen-containing compounds (3), alcohols (2), acids (2) and miscellaneous compounds (10). Among carbonyls, 4 compounds including 2-methylbutanal, 3-methylbutanal, nonanal and benzaldehyde were detected in all samples, while two sulfur containing compounds, dimethyl disulfide and dimethyl trisulfide, were detected in high amounts and considered to be key flavors in black onion extracts. Particularly, thiophenes and 3 sulfur containing compounds (methylpropyl disulfide, methyl-(Z)-propenyl disulfide and methyl-(E)-propenyl disulfide) were detected only in two products. With acetic acid, furfural and pyrazines that formed through Maillard reaction during black onion aging were detected in high amounts in all samples. This also contributed to characteristic flavors such as roasted, sweet, and sour, in the flavor of black onion extracts.

• Korean Journal of Soil Science and Fertilizer
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• v.40 no.3
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• pp.196-200
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• 2007

This study was to determine long-term changes of polycyclic aromatic hydrocarbons (PAHs) in paddy soils. To do this, we analyzed 16 PAHs in soil samples which were stored in the archive of Yeoungnam Agricultural Research Institute, Milyang, Kyeoungnam province, Korea. The samples used in this study were collected every year from 1978 to 2001 at the plough layer (0-12cm). In average, total PAHs accumulated in paddy soil was continuously decreased since 1980 when it peaked to be $237g\;kg^{-1}$. No significant changes were observed for PAHs having 5-6 phenyl rings for the past two decades, whereas PAHs with 3-4 phenyl rings were greatly decreased, reaching at about a half levels of the 1980's. It is worthy to be noted that the large reduction in PAHs with 3-4 phenyl rings has mainly been attributed to the decrease of PAHs in paddy soils for last 20 years. The major compounds accumulated were: phenanthrene > fluoroanthene > chrysene/benzo(b)fluoroanthene. The present results suggest that the switch of main fuels used in Korea from coal to petroleum around at the end of 1970's is likely contributed to decrease in PAH accumulation in paddy soils.

• Korean Journal of Food Science and Technology
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• v.26 no.5
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• pp.500-506
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• 1994

For comparison of beef quality, four kinds of beef (Korean native cattle beef, dairy cattle beef, imported beef, cross-bred beef) were investigated through tenderness, juiciness and flavor related components measurement and organoleptic tests. Flavor related chemical components such as NPN, IMP, free fatty acid and free amino acids were analyzed, water holding capacity, contents of hydroxyproline and intramuscular fat were measured for evaluation of beef tenderness. Instron was also used for measuring beef tenderness as an objective method. Triangle test and descriptive analysis test were conducted for comparison and evaluation of preference of various beef samples. In hardness analysis using Instron, imported and cross-bred beefs had higher value than that of Korean native cattle or dairy cattle beef. Water holding capacity and pH of Korean cattle beef was higher than that of others. The intramuscular fat content of Korean cattle beef was highest, so it was expected juicier than other beef. In flavor related compound analysis, NPN content of Korean native cattle beef was the lowest, which shows it spent the least time among sample meats after slaughter. IMP, hypoxantine and inosine were most abundant in Korean native cattle beef. In free amino acids analysis showed that the proportion of basic acid and aromatic acid content of Korean native cattle beef was highest, whereas that of sulfur containing amino acid of imported beef was highest. TBA value of Korean native cattle beef was the lowest, and analysis of fatty acid composition revealed that the proportion of unsaturated fatty acid of Korean native cattle beef was higher than imported and dairy cattle beef, but similar to cross-bred beef. Organoleptic test was performed by triangle test and descriptive analysis. In triangle test, most panelist could distinguish Korea native cattle beef from imported beef and cross-bred beef, imported beef from cross-bred beef. In descriptive analysis which relys on subjective standards of panelists, there was no difference among beef in aroma, flavor and tenderness except juiciness. Even though contents of non volatile flavor compounds in Korean native cattle beef were higher than those of other beef samples, there were no significant differences in subjective panel test. The results showed that Korean consumers do not have common standards for beef quality evaluation.

• Applied Chemistry for Engineering
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• v.17 no.2
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• pp.210-216
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• 2006

The concentrations of 16 priority PAHs (US EPA standard) were analyzed in the surface sediments obtained from 23 sampling sites near Kwangyang Bay in Korea. There was a local variability in the total PAHs ranged from 0.01 to 171.39 mg/kg, with a mean value of $8.13{\pm}24.8mg/kg$. The major pollution sources of PAHs near Kwanyang Bay were Taeindo, Sueo stream and Wallae stream, whose concentrations were 114.81, 38.37 mg/kg and 19.05 mg/kg, respectively. It showed that PAHs concentrations were increased with the decrease of particle size and with the increase of organic carbon contents in three fractioned sediments. From the analysis of PAHs source using LMW/HMW, Phe/Ant, and Fla/Pyr, pyrolysis by-products were mostly showed in Kwangyang Bay and some place showed the mixure of pyrolysis by-products, and crude oil by-products. Besides, the toxic effects assessment on benthic ecosystem for three major pollution sources showed that the PAHs concentration of Taindo which was mainly accumulated with carcinogenic PAHs exceeds ERM value and the PAHs of Sueo and Wallae streams are the degree of ERL value.