• Journal of the Korean Society of Food Science and Nutrition
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• v.31 no.1
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• pp.75-80
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• 2002

The growth inhibition by nisin-Producing lactococci against Bacillus subtilis and its application to doenjang fermentation were investigated. Lactococcus lactis subsp. lactis IFO 12007, L. lactis subsp. lactis ATCC 7962 and L. lactis subsp. lactis ATCC 11454 were used as nisin-producing lactococci. All of three strain rapidly proliferated to more than 10$^{9}$ CFU/g in steamed soybeans. Only L. lactis subsp. lactis IFO 12007 was in steamed soybean without any pH decrease. In spite of the mild decrease in pH, the growth of B. subtilis was completely inhibited; no living cells were detected in a soybean sample inoculated with 10$^{6}$ CFU/g and incubated for 24 to 72h. The L. lactis subsp. lactis IFO 12007 was applied to doenjang fermentation as a starter culture. It produced high nisin activity in steamed soybean, resulting in the complete growth inhibition of B. subtilis, which had been inoculated at the beginning of the meju fermentation, throughout the process of doenjang production. Over-acidification, which is undesirable for doenjang quality, was successfully prevented simply by adding salt which killed the salt-intolerant L. lactis subsp. lactis IFO 12007. Furthermore, the nisin activity in doenjang disappeared with aging.

• Journal of Soil and Groundwater Environment
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• v.9 no.4
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• pp.15-23
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• 2004

Deicer operations provide traffic safety during winter driving conditions in urban areas. Using large quantities of de-icing chemicals (i.e., $CaCl_2$ and NaCl) can cause serious environmental problems and may change behaviors of heavy metals in roadside sediments, resulting in an increase in mobilization of heavy metals due to complexation of heavy metals with chloride ions. To examine effect of de-icing salt concentration on the leaching behaviors and mobility of heavy metals (cadmium, zinc, copper, lead, arsenic, nickel, chromium, cobalt, manganese, and iron), leaching experiments were conducted on roadside sediments collected from Seoul city using de-icing salt solutions having various concentrations (0.01-5.0M). Results indicate that zinc, copper, and manganese in roadside sediments were easily mobilized, whereas chromium and cobalt remain strongly fixed. The zinc, copper and manganese concentrations measured in the leaching experiments were relatively high. De-icing salts can cause a decrease in partitioning between adsorbed (or precipitated) and dissolved metals, resulting in an increase in concentrations of dissolved metals in salt laden snowmelt. As a result, run-off water quality can be degraded. The de-icing salt applied on the road surface also lead to infiltration and contamination of heavy metal to groundwater.

• Korean journal of food and cookery science
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• v.10 no.1
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• pp.45-50
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• 1994

Conventional Doenjang, three kinds of Improved Doenjang(A; koji: soybean: salt=53: 100: 33, B; koji: soybean: salt=100: 100: 40, C; koji: soybean: salt= 200: 100: 40) prepared with different ratio of koji and salt were made to study the changes in the general contents, characteristics bitter peptides, correlations between bitterness and overall eating quality. 1. Total nitrogen contents increased a little, and amino nitrogen contents in all samples increase markedly. Especially, Amino nitrogen contents of conventrional Doenjang increased more than others. Reducing sugars of doenjang prepared with Asp. oryzae were higher than conventional Doenjang and increased throughout the aging period and Doenjang prepared with Asp. oryzae were more acidic. 2. To characterize bitter peptides in fermented Doenjang, peptides were extracted with 2: 1(v/v) chloroform-methanol and separated by Gel chromato-graphy with Sephadex and TLC. After Gel chromatography and TLC, each fraction examined presence of bitterness and evaluated intensity of bitterness. Amino acid composition of the fractions showing bitter tastes were as follows. Conv. peak 1-1 Trp-(Asp, Arg, Thr, Ser, Glu, Pro)-Phe Imp. A peak 1 Trp-(Glu, Val, Arg, lie)-Phe Imp. B peak 1 Trp-(lie, Pro, Asp, Lys, Val, Glu)-Trp. Imp. C peak 1-2 Trp-(Try, Thr, Glu, Pro, Gly)-Phe 3. Sensory evaluation revealed that correlation coefficient between bitterness and overall eating guality was not high.

• Journal of Korean Society for Atmospheric Environment
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• v.21 no.E1
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• pp.23-35
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• 2005

Size distribution of particulate water-soluble ion components was measured at Gosan, Korea using a micro-orifice uniform deposit impactor (MOUDI). Sulfate, ammonium, and nitrate showed peaks in three size ranges; Sulfate and ammonium were of dominant species measured in the fine mode ($D_{p} < 1.8 {\mu}m$). One peak was observed in the condensation mode ($0.218\sim0.532{\mu}m$), and the other peak was obtained in the droplet mode ($0.532\sim1.8{\mu}m$). Considering the fact that the equivalent ratios of ammonium to sulfate ranged from 0.5 to 1.0 in these size ranges, it is inferred that they formed sufficiently neutralized compounds such as ($NH_{4})_{2}SO_{4} and (NH_{4})_{3}H(SO_{4})_{2}$ during the long-range transport of anthropogenic pollutants. On the other hand, nitrate was distributed mainly in the coarse mode ($3.1\sim6.2{\mu}m$) combined with soil and sea salt. Two sets of MOUDI samples were collected in each season. One sample was collected when the concentrations of criteria air pollutants were relatively high, but the other represented relatively clean air quality. The concentrations of sulfate and ammonium particles in droplet mode were the highest in winter and the lowest in summer. When the air quality was bad, the increase of nitrate was observed in the condensation mode ($0.218\sim0.282{\mu}m$). It thus suggests that the nitrate particles were produced through gas phase reaction of nitric acid with ammonia. Chloride depletion was remarkably high in summer due to the high temperature and relative humidity.

• Proceedings of the Korean Society of Crop Science Conference
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• 2017.06a
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• pp.214-214
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• 2017

Seeds of Tomato (Lycopersicon esculentum Mill.) have demanded high quality because of their high cost of seed. The optimization of the seed priming techniques that have positive effect on fast and uniform germination becomes important at the commercial level. Several factors such as solution composition, osmotic potential, and treatment duration affect seed priming response. In this study, osmotic potentials of priming solution and germination characteristics of primed seed were investigated to clarify the effects different inorganic salt types and the duration. Tomato seeds were primed in osmotic solutions that were osmotic potential ranged -1.54 to -0.45 MPa in an aerated solution of PEG 8000 (17%, 22%, 27%), and inorganic salt solution of $KNO_3$, $Na_2SO_4$, and $K_2SO_4$ (100, 200, 300mM). The seeds were treated at $20^{\circ}C$ for 2, 4, and 6 days. After each treatment, the seeds were dried to moisture content ranged 5-8% at $25^{\circ}C$. Four replications of 25 seeds per each treatments were placed in 10-cm petri dishes containing two filter papers and 3 ml of $dH_2O$ and incubated at $20^{\circ}C/30^{\circ}C$ and $15^{\circ}C$ and seedlings evaluated for abnormality after 14 days of incubation. Seed water potential (${\psi}$) was correlated with water potential of priming solution ($r^2=0.86$). Seeds primed in 100mM $KNO_3$ resulted the highest germination rate (GR, $63.9 %{\cdot}day^{-1}$) and lowest mean germination time (MGT, 2.0 days) comparing to untreated control ($23.9%{\cdot}day^{-1}$ of germination rate and 4.1 days of MGT) at $20/30^{\circ}C$, even though 96% of germination percentage were not different. Seeds primed in 100mM $KNO_3$ (${\psi}=-0.45MPa$) for 4 days showed ${\psi}=-0.38MPa$. Priming in $Na_2SO_4$, $K_2SO_4$, and PEG solution for 6 days improved MGT and GR, but not significantly than 4 days of treatment. Additionally, stepwise osmotic solution treatment with 100mM and 300mM concentration for 6 day did not showed differences with single treatment. In relation to osmotic potentials, identical osmotic potential in different inorganic salt solution showed different effect on germination characteristics.

• Journal of Bio-Environment Control
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• v.26 no.2
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• pp.133-139
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• 2017

This study investigated the effects of NaCl and jasmonic acid (JA) on the growth and physiological responses of spearmint (Mentha spicata L.). Spearmint was hydroponically grown for 3 weeks in modified Hoagland solution containing 0 (untreated control), JA ($20{\mu}M$ JA pretreatment), NaCl (50 mM NaCl treatment) and JA + NaCl ($20{\mu}M$ JA pretreatment + 50 mM NaCl treatment). Growth characteristics, chlorophyll, vitamin C, proline contents, DPPH scavenging activity and inorganic ion contents were evaluated. As a results, there were significant decreases in the plant height, leaf length, leaf width, and fresh weight of plants, treated with NaCl compared with control. On the other hand, the dry matters of shoot and root treated with JA + NaCl combination were better than control or NaCl treatment. Chlorophyll a and b contents in JA treatment was the highest. Vitamin C, antioxidant activity, and proline content in shoot were increased in NaCl treatment which showed low level of growth rate. The K/Na ratio, which is known to indirectly reflect the balance of ion uptake, was higher in a single treatment of JA than the control group, while lower in salt treatment (NaCl and JA + NaCl) because of high $Na^+$ absorption. In conclusion, these results showed that moderate stress treatment such as low level salt treatment and plant growth regulator jasmonic acid (JA) application would be potential strategies to improve the quality of spearmint by inducing the accumulation of secondary metabolites containing high antioxidant activity and essential oil.

• Food Science and Preservation
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• v.12 no.3
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• pp.292-298
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• 2005

Kochujang(Korean red pepper paste) of 600 g was fermented in the different types of vessels (glass, polypropylene(PP), polyethylene terephthalate(PET), stainless steel and Korean porcelain called onggi) with 627 mL of volume during 4 months. The quality changes were monitored for physical, chemical and microbiological attributes. Onggi which had high porosity in the micro-structure provided kochujang with higher microbial counts of aerobic bacteria, lactic acid bacteria and yeasts than those of the other containers. Compared to kochujang fermented in the other containers, kochujang in Onggi showed higher protease activity, amino type nitrogen, and free amino acid content. The kochujang in Onggi also attained higher acidity, lower pH and higher reducing sugar concentration than those in the other containers. All changes were completed 2 or 3 months. Onggi showed water loss and salt increase of the kochujang comparable to those in the other vessels, which was from gradual clogging of the micropores during storage. All physical, chemical and microbiological changes made the kochujang in Onggi attain the sensory quality significantly better than those fermented in the other vessels.

• Journal of Environmental Science International
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• v.23 no.6
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• pp.1037-1047
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• 2014

A highly sensitive analytical method based on stir bar sorptive extraction (SBSE) technique and gas chromatography/tandem mass spectrometry (GC/MS-MS) has been developed, allowing the simultaneous multi-analyte determination of seven UV filters in water samples. The stir bar coated with polydimethylsiloxane (PDMS) was added to 40 mL of water sample at pH 3 and stirred at 1,100 rpm for 120 min. Other SBSE parameters (salt effect and presence of organic solvent) were optimised. The method shows good linearity (coefficients > 0.990) and reproducibility (RSD < 12.9%). The extraction efficiencies were above 84% for all the compounds. The limits of detections (LOD) and limits of quantification (LOQ) were 2.1~8.6 ng/L and 6.8~27.5 ng/L, respectively. The developed method offers the ability to detect 8 UV filters at ultra-low concentration levels with only 40 mL of sample volume. Matrix effects in tap water, river water, wastewater treatment plant (WWTP) final effluent water and seawater were investigated and it was shown that the method is suitable for the analysis of trace level of 7 UV filters except of benzophenone (BP). The method developed in the present study has the advantage of being rapid, simple, high-sensitive and both user and environmentally friendly.

• Korean journal of food and cookery science
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• v.25 no.6
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• pp.747-757
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• 2009

The purpose of this study was to enhance the quality of kochujang Apple juice was added to traditional Kochujang at 0%, 20%, 40%, 60 and 80%. Physicochemical and microbial characteristics were periodically investigated during at room temperature during a 90 day fermentation period. The moisture content of the apple Kochujang was higher than that of the control, while the salt content of the apple Kochujang was lower than that of the control, At first, the sweetness of the apple Kochujang showed no significant difference from the control; however, its sweetness increased during the 90 days. In all treatments, the pH value decreased during the fermentation period, while the titratable acidity increased during the fermentation period. Viscosity decreased greatly after 30 days. Sugar reduction was higher in the apple Kochujang than in the control, and its concentration increased with apple juice content. According to the analysis of free sugar, glucose, fructose, and maltose had an especially high ratio in the apple Kochujang. The organic acids detected in Kochujang were citric acid, malic acid, oxalic acid and lactic acids. The content of citric acid and malic acid were higher than the other acids in the apple Kochujang. L, a, and b values generally decreased during the fermentation period. When the Kochujang was made, the number of the total viable cells was $10^7\;CFU/g$. At room temperature, the number steadily increased up to the 30th day, then steadily decreased on the 90th day. After that, there was no significant change. The number of yeasts was $10^6\;CFU/g$ at the end of the 90th day. After the 90th day of fermentation, sensory results showed that the 60~80% apple juice Kochujang showed the best taste, appearance, texture, and overall quality.

• Korean journal of food and cookery science
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• v.22 no.1 s.91
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• pp.69-79
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• 2006

Traditional doenjang with Lentinus edodes added at a concentration of 0, 3, 5 and 10% (w/w) was prepared and its physicochemical characteristics were analyzed during fermentation for 6 months. The moisture content, salt level and pH for doenjang were decreased with increasing addition of Lentinus edodes powder, but crude protein content was increased. Among the free sugars, glucose, galactose, arabinose, sucrose and maltose were identified and quantified, with the first two being the major free sugar. Minerals were detected in the order of Na> K> P> Ca> Mg> Fe while the content of Cu, Mn and Zn exhibited little change. The contents of each amino acid of traditional doenjang with added Lentinus edodes, glutamic, leucine and aspartic acids, had a much higher level. In fatty acid compositions, palmitic, stearic, oleic and linoleic acids were analyzed, with oleic acid being the most abundant fatty acid at $56.4{\pm}0.8\sim57.5{\pm}0.5%$ in all the tested samples. GMP and IMP contents of nucleotides and their related compounds were extremely high. It was thought that these substances contributed to the sweet taste of traditional doenjang with added Lentinus edodes. These results showed the applicability and high quality of traditional doenjang with added Lentinus edodes.