• Korean journal of applied entomology
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• v.47 no.4
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• pp.447-456
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• 2008

Five effective strains against tobacco cutworm, Spodoptera litura (Lepidoptera: Noctuidae), Steinernema carpocapsae (GSN1), Steinernema sp. (GSNUS-10), Steinernema sp. (GSNUS-14), Heterorhabditis bacteriophora Hamyang (HbH), and Heterorhabditis sp. (GSNUH-1) were selected among 14 isolates of Korean entomopathogenic nematode in laboratory tests. $LC_{50}$ values of above five strains against tobacco cutworm were various by different nematode strains and developmental stages of tobacco cutworm. $LC_{50}$ value of S. carpocapsae (GSN1) was the lowest by $4.0{\sim}8.3$ infective juveniles (Ijs) and 2nd instars of tobacco cutworm was most susceptible. Pathogenicity of five effective strains against tobacco cutworm depends on nematode strain, concentration, and application times. The most effective strain was determined as S. carpocapsae (GSN1). Two or three times of applications were effective regardless of nematode strain, or concentration. Efficacy of S. carpocapsae (GSN1), Steinernema (GSNUS-10), Steinernema (GSNUS-14), and Heterorhabditis (GSNUH-1) was variable depending on nematode strain, concentration, application times, and host variety. S. carpocapsae (GSN1) was the most effective and inoculation of 100,000 infective juveniles per m2 (720,000 Ijs/7.2 $m^2=1{\times}10^9$ Ijs/ha) resulted in higher efficacy. Three times of application of nematodes led to higher control efficacy than one or two applications. Efficacy of nematodes was higher on Chinese cabbage than cabbage or kale.

• Korean Journal of Environment and Ecology
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• v.25 no.2
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• pp.156-165
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• 2011

It is selected seven sites for marine algal flora and community structure and investigated seasonally from December 2008 to November 2009 in Gogunsan Islands, the west coast of Korea. A total of 58 species including 10 green, 16 brown and 32 red algae were collected and identified. Among these species, 11 species were found throughout the year. Annual mean biomass in dry weight were 213.8 g $m^{-2}$ at Sinsido 1, 143.1 g $m^{-2}$ at Sinsido 2, 133.3 g $m^{-2}$ at Sinsido 3, 164.0 g $m^{-2}$ at Munyeodo, 116.9 g $m^{-2}$ at Seonyudo, and 145.1 g $m^{-2}$ at Jangjado. Maximum biomass was recorded in Sinsido 1, and minimum mean biomass was Sinsido 4. The dominant species based on biomass were Sargassum thunbergii, Ulva pertusa, Sargassum fusiforme and Corallina pilulifera. S. thunbergii was the representative alga occurred at all seasons. The flora investigated could be classified into six functional groups such as coarsely branched form (46.6%), filamentous form (27.6%), sheet form (17.2%), thick leathery form (3.4%), jointed calcareous form (3.4%) and crustose form (1.7%). The R/P, C/P and (R+C)/P value reflecting flora characteristics were 0.33~0.75, 1.11~2.50, 1.47~3.25, respectively. Diversity index (H') and dominance index (DI) indicated that stability of seaweed community of Gogunsan Islands was unstable and environmental conditions were bad. According to multidimensional scaling (MDS) and cluster analysis, Gogunsan Islands were divided into three distinct groups. The first group was Sinsido 2, Sinsido 3, Seonyudo and Muyeodo and the second group comprised Sinsido 1 and Jangjado and the other was Sinsido 4 due to meaningful difference in similarity.

• Journal of the Korean Society of Food Science and Nutrition
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• v.46 no.3
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• pp.335-342
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• 2017

In this study, we investigated the physicochemical quality characteristics and antioxidant activities of water extracts ($20^{\circ}C$ and $95^{\circ}C$) against different parts (leaf and petiole) from Wasabia japonica (wasabi). Water extracts were divided into six types of wasabi powders: leaf hot air dried (LD), petiole hot air dried (PD), whole (leaf+petiole) hot air dried (WD), leaf steamed and hot air dried (LSD), petiole steamed and hot air dried (PSD), and whole steamed and hot air dried (WSD). Turbidity was higher in wasabi $20^{\circ}C$ water extracts than in $95^{\circ}C$ hot water extracts. Browning degree was higher in wasabi leaf extracts than in petiole extracts. The pH of hot water extraction was lower than that of room temperature extraction. Wasabi extracts did not show much difference in Hunter's color values according to extraction temperature, expected that b value of yellowness was significantly higher in leaf extracts than in petiole extracts. Carbazole pectin contents of leaf extracts were significantly higher than in petiole extracts, however water soluble pectin was higher in petiole extracts. The total polyphenol contents of LD20 and LD95 were 1,561.43 mg gallic acid equivalent (GAE)/100 g and 1,163.02 mg GAE/100 g, respectively, and total polyphenols decreased during hot water extraction. Extracts from different parts of wasabi showed a significant difference in total flavonoid contents. Total flavonoid contents of LD20, LD95, PD20, and PD95 were 554.44 mg/100 g, 396.65 mg/100 g, 55.42 mg/100 g, and 47.68 mg/100 g, respectively. In the sensory evaluation, LD95 extract showed significantly higher values than other samples in terms of color, flavor, taste, mouth feeling, and overall acceptability. In the analysis of sourness, saltiness, umami, sweetness, and bitterness taste by an electronic tongue, the sourness values of LD20 and PSD95, saltiness values of WSD20 and WSD95, and umami values of PD20 and PD95 were significantly higher than other extracts. The results of this study suggest that wasabi leaf and petiole extracts enhance qualities and antioxidant activities when used different parts together.

• Korean Journal of Agricultural Science
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• v.41 no.4
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• pp.415-424
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• 2014

This study was carried out to determine the effect of storage condition, such as temperature or relative humidity (RH) in home-style refrigerator, on the change of quality traits and storage characteristics of Hanwoo M. longissimus to find out the condition for prolongation of shelf-life with maintaining the meat quality for consumers. Samples were sliced in $1{\pm}0.2cm$ thickness, and packed in foamed polystyrene tray with linear low-density polyethylene (LLD-PE) film to simulate the pre-packed Hanwoo loin sold in retail market, then stored in home-style refrigerator ($5^{\circ}C$/17% RH, Control), and chambers of $5^{\circ}C$/55% RH (T1), $5^{\circ}C$/85% RH (T2), and $-1^{\circ}C$/99% RH (T3), respectively. Quality traits (color, pH, water holding capacity, shear force and grilling loss) and storage characteristics (thiobarbituric acid reactive substances, volatile basic nitrogen and total microbes) were measured at 1, 4, 7, 14 and 21 days after storage. Lightness of Hanwoo loin stored in T1, T2 and T3 were higher than that of control until 14 days of storage, however at the end of storage (21 days) control showed significantly higher than other treatments (p<0.05). Redness and Yellowness of Hanwoo loin samples stored in T1 and T3 were significantly higher than others during all storage period (p<0.05). The water holding capacity (WHC) of control was significantly higher than others until 14 days of storage (p<0.05), however, Hanwoo loin stored in T2 was the highest ($63.64{\pm}7.62kg/cm^2$) at 21 days of storage. Hanwoo loin stored in T1 showed significantly lower shear force than others during all storage period (p<0.05). There was no consistent tendency in pH and grilling loss during storage in all treatments. Hanwoo loin stored in T1 showed lower TBARS value than others during storage period, however there was a rapid increase to $0.34{\pm}0.27mg$ malonaldehyde/kg meat at 21 days of storage. And, all the treated samples (from T1 to T3) showed significantly lower VBN values at 21 days of storage (p<0.05). The population of total aerobic microbes were significantly increased in all treatments as storage period increasing, and the population of T3 ($2.28{\pm}0.57logCFU/g$) was the lowest at 21 days of storage (p<0.05). From those results, it could be predicted the better storage condition to maintain the meat quality and prolong the shelf-life of Hanwoo loin by lowering the temperature and adjusting the humidity about 55%.

• Food Science and Preservation
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• v.21 no.6
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• pp.790-798
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• 2014

The nutritional compositions and antioxidative activities of the Kimcheon lowbush and Pyungtaek highbush blueberries cultivated in South Korea were investigated. The approximate compositions, pH, and soluble-solid and mineral contents of P, Ca, Mg, Na, and Zn were determined. Both blueberry cultivars had mainly fructose and glucose as free sugars while disaccharides such as sucrose, maltose, and lactose were not detected in both. Oleic, linoleic, and linolenic fatty acids were the major fatty acids in both types of blueberries. The total of 16 free amino acids, including seven essential and nine non-essential amino acids, were higher in the Pyungtaek highbush blueberry. Among the amino acids, arginine was especially much higher in the Pyungtaek highbush blueberry. The anthocyanin, resveratrol, and polyphenol compounds, which are the important biologically active compounds in blueberries, were found. The anthocyanin contents of the Kimcheon lowbush and Pyungtaek highbush blueberries were 22.0 and 18.1 mg/100 g, respectively; the resveratrol contents by HPLC, 0.12 and 0.11 mg/100 g; and the total polyphenol contents, 141.3 and 138.4 mg/100 g. The electron-donating ability determined based on the DPPH radical scavenging activity was increased in a concentration-dependent manner, and it was higher than that of the Pyungtaek highbush blueberries, which implies that it is highly correlated with the higher amounts of total polyphenol, anthocyanin, and resveratrol in it. In conclusion, the two varieties of Korean blueberries can be suggested as potential sources of high-value-added functional foods.

• Journal of Wetlands Research
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• v.22 no.1
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• pp.24-30
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• 2020

To assess the wetland systems' capability to reduce fine dust, we used an artificial wetland module of small-sized greenhouse (70cm W × 70cm L × 60cm H) which creates a closed system. Experiment was performed twice using four species in each experiment. Non-plantation, one species, or two species condition was created in each mesocosm. We measured air quality, primarily PM2.5 and PM10 at the initial open mesocosms and 1hr later since mesocosms were closed. The dry weight of vegetation was measured at the 2nd experiment. The decreased amount of PM2.5 and PM10 was 13.7±1.3 and 13.2±1.3 ㎍·m^-3hr^-1 in wetland condition and 15.0±1.4 and 13.8±1.5 ㎍·m^-3hr^-1 in dryland condition, respectively. In 2^nd experiment, the decreased amount of PM 2.5 and PM 10 in wetland condition was 13.7±1.3 and 9.2±1.5 ㎍·m^-3hr^-1, 15.0±1.4 and 8.8±1.4 ㎍·m^-3hr^-1 in dryland condition, respectively. Wetland showed higher removal effect due to its high productivity leading to more effective absorption of particulate matter. Furthermore, the aquatic characteristics of wetland system and high humidity helped purifying the air quality. This can be seen as another value of wetlands, which can be presented as one of the solutions to the problem of fine dust.

• Radiation Oncology Journal
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• v.19 no.2
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• pp.163-170
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• 2001

Purpose : The measurement of radiation survival using a clonogenic assay, the established standard, can be difficult and time consuming. In this study, We have used the MTT assay, based on the reduction of a tetrazolium salt to a purple formazan precipitate by living cells, as a substitution for clonogenic assay and have examined the optimal condition for performing this assay in determination of radiation sensitivity. Materials and Methods : Four human cancer cell lines - PCI-1, SNU-1066, NCI-H630 and RKO cells have been used. For each cell line, a clonogenic assay and a MTT assay using Premix WST-1 solution, which is one of the tetrazolium salts and does not require washing or solubilization of the precipitate were carried out after irradiation of 0, 2, 4, 6, 8, 10 Gy. For clonogenic assay, cells in $25\;cm^2$ flasks were irradiated after overnight incubation and the resultant colonies containing more than 50 cells were scored after culturing the cells for $10\~14$ days. For MTT assay, the relationship between absorbance and cell number, optimal seeding cell number, and optimal timing of assay was determined. Then, MTT assay was performed when the irradiated cells had regained exponential growth or when the non-irradiated cells had undergone four or more doubling times. Results : There was minimal variation in the values gained from these two methods with the standard deviation generally less than $5\%$, and there were no statistically significant differences between two methods according to t-test in low radiation dose (below 6 Gy). The regression analyses showed high linear correlation with the $R^2$ value of $0.975\~0.992$ between data from the two different methods. The optimal cell numbers for MTT assay were found to be dependent on plating efficiency of used cell line. Less than 300 cells/well were appropriate for cells with high plating efficiency (more than $30\%$). For cells with low plating efficiency (less than $30\%$), 500 cells/well or more were appropriate for assay. The optimal time for MTT assay was after 6 doubling times for the results compatible with those of clonogenic assay, at least after 4 doubling times was required for valid results. In consideration of practical limits of assay (12 days, in this study) cells with doubling time more than 3 days were inappropriate for application. Conclusion : In conclusion, it is found that MTT assay can successfully replace clonogenic assay of tested cancer cell lines after irradiation only if MTT assay was undertaken with optimal assay conditions that included plating efficiency of each cell line and doubling time at least.

• Journal of Food Hygiene and Safety
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• v.15 no.4
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• pp.328-333
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• 2000

This study was carried out to changes in chemical and microbiological properties of spring waters in Tongyeoung area. In this paper, ninety spring water samples were collected from 9 station for 11 month to evaluated chemical and bacteriological water quality. Range and mean values of constituents of the samples are as followed; water temperature 5.2~25.8$^{\circ}C$, 16.3$^{\circ}C$, pH 6.0~7.2, 6.7, total residue 33.6~210 mg/1, 90.6 mg/1, turbidity 0.35~5.48, 1.45NTU, KMnO4 consumed 0.51~4.21 mg/1, 1.39 mg/1, chloride ion 6.23~42.5, 16.7 mg/l, phosphate-phosphorus ND-0.04, 0.02 mg/1, nitrite-nitrogen ND~0.02, 0.01 mg/1, nitrate-nitrogen ND~3.56, 1.42 mg/1, ammonia-nitrogen ND~0.20, 0.14 mg/1, dissolved total nitrogen ND~3.78, 1.57 mg/1, iron 0.04~0.28, 0.13ppm, zinc 0.03~0.66, 0.20ppm, mangan ND~0.01, allumium 0.14~0.58, 0.39ppm, copper ND~0.01, 0.01, lead ND~0.01, 0.01ppm, Arsenic ND~0.01, 0.01ppm, mercury ND~0.02, chrome not detected, cadmium not detetced respectively. The viable cell counts of the spring waters ranged 5.0~760/m1(means 130/m1). Range and mean value of total coliform and focal coliform MPN's of the spring waters were 0~2,400MPN/100 ml, 73MPN/100 ml and 0~540MPN/100 ml, 21MPN/100 ml. Spring water quality was usually poor with viable cell counts exceeding 130 CFU/liter and the coliform counts in spring waters of 73 MPN/liter. Composition of coliform by IMViC reaction was 33.3% E. coli, 15.6% Citrobacter freundii, 35.6% Klebsiella aerogenes and others.

• Journal of the Korean Society of Food Science and Nutrition
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• v.35 no.5
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• pp.613-621
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• 2006

This study was performed to evaluate the storage quality of milk bread added with $\beta$-glucan (10 20 and 30%), which is a functional food material produced from Agrobacterium spp. R259 KCTC 10197BP. During storage ($20^{\circ}C$, 40% relative humidity) the pH of all breads gradually increased, although there were no significant differences in pH of the $\beta$-glucan added milk bread from those of the control. During storage, the moisture content of all groups decreased, however, moisture contents in the $\beta$-glucan added breads were higher than that in the control. Hunter color values ($L^*,\;a^*\;and\;b^*\;value$) of the milk bread added upto 20% $\beta$-glucan were not significantly different, but the lightness increased during storage. Rapid increase of hardness in the milk bread during storage was observed in control, while the hardness of $\beta$-glucan added bread increased slowly. Also, the degree of retrogradation of bread decreased as $\beta$-glucan addition amount increased. Sensory evaluation showed that the score of over-all acceptability of the bread added with 20% $\beta$-glucan was the highest among treated groups until four days of storage. This study confirmed that the addition of $\beta$-glucan to milk bread maintained the moisture content and delayed hardness during storage.

• Asian-Australasian Journal of Animal Sciences
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• v.22 no.6
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• pp.836-842
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• 2009

The objectives of this study were to evaluate potential benefits of intercropping of corn with runner bean for a smallsized farming system, based on land equivalent ratio (LER) and silage yield and quality of corn intercropped with runner bean (Phaseolus vulgaris L.), in arid conditions of Turkey under an irrigation system. This experiment was established as a split-plot design in a randomized complete block, with three replications and carried out over two (consecutive) years in 2006 and 2007. Seven different mixtures (runner bean, B and silage corn sole crop, C, 10% B+90% C, 20% B+80% C, 30% B+70% C, 40% B+60%C, and 50% B+50%C) of silage corn-runner bean were intercropped. All of the mixtures were grown under irrigation. The corn-runner bean fields were planted in the second week of May and harvested in the first week of September in both years. Green beans were harvested three times each year and green bean yields were recorded each time. After the 3rd harvest of green bean, residues of bean and corn together were randomly harvested from a 1 $m^{2}$ area by hand using a clipper when the bean started to dry and corn was at the dough stage. Green mass yields of each plot were recorded. Silages were prepared from each plot (triplicate) in 1 L mini-silos. After 60 d ensiling, subsamples were taken from this material for determination of dry matter (DM), pH, organic acids, chemical composition, and in vitro DM digestibility of silages. The LER index was also calculated to evaluate intercrop efficiencies with respect to sole crops. Average pH, acetic, propionic and butyric acid concentrations were similar but lactic acid and ammonia-N levels were significantly different (p<0.05) among different mixtures of bean intercropped with corn. Ammonia-N levels linearly increased from 0.90% to 2.218 as the percentage of bean increased in the mixtures up to a 50:50 seeding ratio. While average CP content increased linearly from 6.47 to 12.45%, and average NDF and ADF contents decreased linearly from 56.17 to 44.88 and from 34.92 to 33.51%, respectively, (p<0.05) as the percentage of bean increased in the mixtures up to a 50:50 seeding ratio, but DM and OM contents did not differ among different mixtures of bean intercropped with corn (p>0.05). In vitro OM digestibility values differed significantly among bean-corn mixture silages (p<0.05). Fresh bean, herbage DM, IVOMD, ME yields, and LER index were significantly influenced by percentage of bean in the mixtures (p<0.01). As the percentage of bean increased in the mixtures up to a 50:50 seeding ratio, yields of fresh bean (from 0 to 24,380 kg/ha) and CP (from 1,258.0 to 1,563.0 kg/ha) and LER values (from 1.0 to 1.775) linearly increased, but yields of herbage DM (from 19,670 to 12,550 kg/ha), IVOMD (from 12,790 to 8,020 kg/ha) and ME (46,230 to 29,000 Mcal/ha) yields decreased (p<0.05). In conclusion, all of the bean-corn mixtures provided a good silage and better CP concentrations. Even though forage yields decreased, the LER index linearly increased as the percentage of bean increased in the mixture up to a 50:50 seeding ratio, which indicates a greater utilization of land. Therefore, a 50:50 seeding ratio seemed to be best for optimal utilization of land in this study and to provide greater financial stability for labor-intensive, small farmers.