• Journal of the Korean Society of Food Science and Nutrition
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• v.45 no.6
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• pp.923-928
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• 2016

To increase the consumption of head-type kimchi cabbage leaves as fresh food ingredients, the physicochemical composition was investigated depending on leaf parts. Kimchi cabbage leaves were divided into three portions, such as outer (L1), mid (L2), and inner (L3), and their proximate compositions were determined along with dietary fiber, free sugar, organic acid, free amino acid, and mineral contents. Contents of moisture, crude protein, and crude fat were highest in L1, whereas contents of crude ash and carbohydrate were highest in L3 (P<0.05). Calories ranged 24.5~26.5 kcal/100 g with no significant difference among leaf parts, and dietary fiber content of L1 was highest (P<0.05). Fructose, glucose, and sucrose contents were highest in L3 (P<0.05). Citric acid, malic acid, and succinic acid were detected, and contents of citric acid and malic acid were highest in L3, in contrast, succinic acid was highest in L1 (P<0.05). Glutamic acid, constituting over 30% of the total free amino acid contents, was highest in L3, whereas ${\gamma}-aminobutyric$ acid contents were highest in L1 (P<0.05). K, Na, Ca, and Mg were the major minerals in head-type kimchi cabbage, and their contents showed no significant differences (P<0.05). It can be proposed that marketing of head-type kimchi cabbage as a fresh-cut vegetable could be enhanced due to the different quality characteristics of its leaf parts.

• Biotechnology and Bioprocess Engineering:BBE
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• v.10 no.4
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• pp.289-295
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• 2005

In this study, the cultural medium used for the efficient production of $\gamma$-PGA with a newly isolated Bacillus sp. RKY3 was optimized. It was necessary to supplement the culture medium with L-glutamic acid and an additional carbon source in order to induce the effective production of $\gamma$-PGA. The amount of $\gamma$-PGA increased with the addition of L-glutamic acid to the medium. The addition of 90 g/L L-glutamic acid to the medium resulted in the maximal yield of $\gamma$-PGA (83.2 g/L). The optimum nitrogen source was determined to be peptone, but corn steep liquor, a cheap nutrient, was also found to be effective for $\gamma$-PGA production. Both the $\gamma$-PGA production and cell growth increased rapidly with the addition of small amounts of $K_2HPO_4$ and $MgSO_4\cdot7H_{2}O$. Bacillus sp. RKY3 appears to require $Mg^{2+}$, rather than $Mn^{2+}$, for $\gamma$-PGA production, which is distinct from the production protocols associated with other, previously reported bacteria. Bacillus sp. RKY3 may also have contributed some minor $\gamma$-PGA depolymerase activity, resulting in the reduction of the molecular weight of the produced $\gamma$-PGA at the end of fermentation.

• Korean Journal of Soil Science and Fertilizer
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• v.47 no.6
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• pp.432-436
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• 2014

While searching for healthier diets, people became more attentive to agricultural organic products. However, organic foods may be more susceptible to microbiological contamination because of the use of livestock manure compost and liquid manure, potential sources of pathogenic bacteria. This study was undertaken to investigate the persistence of Salmonella enterica, Escherichia coli O157:H7, and Listeria monocytogenes in soil, liquid manure amended soil, and liquid manure. Loamy soil, liquid manure amended soil, and liquid manure were inoculated with S. enterica, E. coli O157:H7, and L. monocytogenes. Samples were incubated in consistent moisture content at $25^{\circ}C$. Samples had been periodically collected during 120 days depending on the given conditions. S. enterica and E. coli O157:H7 survived over 120 days in loamy soil and over 60 days in liquid manure amended soil, respectively. L. monocytogenes decreased faster than other pathogens in soil. S. enterica, E. coli O157:H7, and L. monocytogenes survived for up to 5 days in liquid manure. S. enterica and E. coli O157:H7 in soil decreased by 2 to $2.5log\;CFU\;g^{-1}$ for 120 days. S. enterica and E. coli O157:H7 in liquid manure amended soil decreased slowly for 21 days. However, S. enterica, E. coli O157:H7, and L. monocytogenes sharply decreased after 21 days. S. enterica, E. coli O157:H7, and L. monocytogenes in soil increased by 0.5 to $1.0log\;CFU\;g^{-1}$ for 7 days. Foodborne pathogens in soil and liquid manure amended soil gradually decreased over time.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.40 no.6
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• pp.343-349
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• 2007

This study examined the effective utilization of pearl processing by-products. Three extracts of hot-water extract (WE), hydro-cooked extract (HE), and two-step enzymatic hydrolysate (EH) were prepared from pearl oyster muscle, and their characteristics were examined. The moisture, crude protein, volatile basic nitrogen (VBN), and amino-N contents were 97.5-98.0%, 0.5-1.3%, 2.1-4.9 g/100 mL, and 35.0-74.5 g/100 mL, respectively. EH had the lowest VBN and highest amino-N contents. In addition, EH had the highest yields. In terms of its functional properties, EH inhibited angiotensin-I converting enzyme ($IC_{50}$, 1.39 mg/mL) more strongly than the other extracts ($IC_{50}$, 4.17-7.95 mg/mL). The free amino acid contents of WE, HE, and EH were 661, 470 and 1,150 mg/100 mL, respectively. Major amino acids were taurine and glutamic acid. Major inorganic ions were Na, Mg, and Ca. Contents of taste compounds, such as free amino acids, inorganic ions, and quaternary ammonium bases, differed significantly according to the extract methods. Based on the results of chemical experiments and sensory evaluation, the quality of EH was superior to the other extracts, and EH is suitable for use in natural flavoring materials.

• Food Quality and Culture
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• v.3 no.1
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• pp.34-39
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• 2009

This study assessed the efficacy of aqueous chlorine dioxide ($ClO_2$) and commercial chlorine sanitizer in terms of its ability to eliminate Listeria monocytogenes, Salmonella Typhimurium, and Escherichia coli O157:H7 on radish sprouts (Raphanus sativus L.). Radish sprouts were inoculated with a cocktail containing one each of three strains of three different foodborne pathogens, then treated with distilled water (control) or chemical sanitizers (100 ppm commercial chlorine, and 50, 100, 200 ppm $C1O_2$) for 1, 5, and 10 min at room temperature ($22{\pm}2^{\circ}C$). Populations of S. Typhimurium, E. coli O157:H7 and L. monocytogenes were counted at 4.64, 6.05, and 4.29 log CFU/g, respectively, after inoculation. Treatment with water did not significantly reduce the levels of any of the three foodborne pathogens. The levels of all three pathogens were reduced by treatment with chemical sanitizers; however, the observed levels of reduction of E. coli O157:H7 and L. monocytogenes were not significant as compared with the controls. The levels of the three pathogens were reduced most profoundly when treated for 10 min with 200 ppm of $C1O_2$, and the reduction levels of S. Typhimurium, E. coli O157:H7, and L. monocytogenes were 1.17, 1.63, and 0.96 log CFU/g, respectively. When chemically injured cells were investigated using SPRAB for E. coli O157 :H7 and by selective overlay methods for S. Typhimurium and L. monocytogenes, respectively, it was noted that commercial chlorine sanitizer generated more numbers of injured pathogens than did $C1O_2$. These data indicate that $C1O_2$ treatment may prove useful in reducing the numbers of pathogenic bacteria in radish sprouts.

• Journal of Ginseng Research
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• v.29 no.2
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• pp.107-112
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• 2005

The objective of this study was to determine effects of the die temperature(100 and $120^{\circ}C$) and screw speed(200 and 300 rpm) on the characteristics of extruded raw ginseng such as crude saponin, ginsenosides, maltol and the color of powder. Crude saponin content increased after extrusion-cooking. Ginsenoside $Rg_1\;and\;Rg_2$ that contained in red ginseng increased from 0.2275 mg/g to 0.2835 mg/g$(Rg_l)$ and 0.1164 mg/g to 0.2230 mg/g$(Rg_2)$ with the increase in die temperature from 100 to $120^{\circ}C$, which increased with the decrease in screw speed from 300 to 200 rpm. Maltol, specific component in red ginseng was detected in extruded ginseng. Total sugar content was not changed by extrusion process, however reducing sugar decreased with the increase in die temperature from 100 to $120^{\circ}C$. In conclusion extrusion process can be applied to red ginseng manufacturing by controling extrusion process variables such as extrusion temperature and screw speed.

• Journal of the Korean Society of Tobacco Science
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• v.30 no.2
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• pp.117-124
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• 2008

A solid phase microextraction (SPME) method in combination with gas chromatography/mass spectrometric techniques was used for the extraction and quantification of 12 selected agrochemical residues in tobacco. The parameters such as the type of SPME fiber, adsorption/desorption time and the extraction temperature affecting the precision and accuracy of the SPME method were investigated and optimized. Among three types of fibers investigated, polyacrylate (PA), polydimethylsiloxane (PDMS) and polydimethylsiloxane-divinylbenzene (PDMS-DVB), PDMS fiber was selected for the extractions of the agrochemicals. The SPME device was automated and on-line coupled to a gas chromatograph with a mass spectrometer. Mass spectrometry (MS) was used and two different instruments, a quadrupole MS and triple quadrupole MS-MS mode, were compared. The performances of the two GC-MS instruments were comparable in terms of linearity (in the range of 0.01$\sim$0.5 $\mu$g/mL) and sensitivity (limits of detection were in the low ng/mL range). The triple quadrupole MS-MS instrument gave better precision than that of quadrupole MS system, but generally the relative standard deviations for replicates were acceptable for both instruments (< 15%). The LODs was fully satisfied the requirements of the CORESTA GRL. Recoveries of 12 selected agrochemicals in tobacco yielded more than 80% and reproducibility was found to be better than 10% RSD so that SPME procedure could be applied to the quantitative analysis of agrochemical residues in tobacco.

• Analytical Science and Technology
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• v.16 no.6
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• pp.488-498
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• 2003

By LC/MS/MS, the analytical method of sildenafil and its analogues (homosildenafil, vardenafil and tadalafil) used as used medical treatment of impotence was established. electrosprary ionization (ESI) and atmospheric pressure chemical ionization (APCI) as a ionization method were applied. Several parameter were varied and the sensitivity and reproducibility were compared. In LC/ESI-MS method, capillary voltage, cone voltage, extractor, entrance and RF lens to create appropriate productr ions for multiple reaction monitoring (MRM) were variable parameter, but the formation of the other product ions except the precursor ion could not detect. And the value of entrance, collision energy, exit, corona voltage, cone voltage, extractor, RF lens, cone gas, and desolvation gas in APCI mode were varied, only the creation pattern of fragment ions by the change of RF lens value were detected, and the limit of detection was decreased due to the increase of S/N. Ten millimole ammonium formate (pH 4.8):acetonitrile=70:30 by isocratic elution in HPLC system was shown the maximum sensitivity in MS, the detection limit of sildenafil, homosildenafil, vardenafil and tadalafil obtained by ESI-MRM were 0.10, 0.025, 0.025, and $0.25{\mu}g/mL$ at S/N>5, respectively.

• 한국생물공학회:학술대회논문집
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• 2003.04a
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• pp.284-287
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• 2003

Effects of ultrasound on cell growth and the production of human granulocyte-macrophage colony-stimulating factor (hGM-CSF) were investigated using transgenic Nicotiana tabacum cell suspension cultures. The culture suffered a slight growth depression immediately after the sonication, but gradually recovered to normal growth within 2 days. When the cells were exposed to ultrasound, the level of secreted hGM-CSF was 2.14 times higher than that in normal condition. From the beginning to 6 days of culture, production of secreted hGM-CSF was higher than that of control and then decreased. At the end of culture, however, hGM-CSF was considerably increased up to 36.7%. In the case of intracellular hGM-CSF, the level was slightly higher than that obtained in normal condition. Total hGM-CSF production was 31.5% higher than that of control culture after 6 days. The highest amount of hGM-CSF was $34.9\;{\mu}g/L$.

• Biotechnology and Bioprocess Engineering:BBE
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• v.6 no.1
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• pp.6-10
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• 2001

The production of chitosan from the mycelia of Absidia coerulea was studied to improve cell growth and chitosan productivity. Culture conditions were optimized in batch cultivation (pH 4.5, agitator speed of 250 rpm, and aeration rate of 2 vvm) and the maximum chitosan concentration achieved was 2.3g/L under optimized conditions. Continuous culture was carried out successfully by the formation of new growth spots under optimized conditions, with a chitosan productivity of 0.052g/L(sup)-1 h(sup)-1, which is the highest value to date, and was obtained at a dulution rate of 0.05h(sup)-1. Cell chitosan concentrations reached about 14% in the steady state, which is similar to that achieved in batch culture. This study shows that for the continuous culture of Absidia coerulea it is vital to control the medium composition.