• Korean Journal of Environmental Biology
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• v.34 no.4
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• pp.223-232
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• 2016

Drought is one of important environmental stress for plant. Drought has deleterious effect to plant growth including maize (Zea mays L.) such as vegetative and/or reproductive growth, root extension, photosynthesis efficiency, flowering, anthesis-silking interval (ASI), fertilization, and grain filling. In this study, we screened drought tolerant maize in 21 cultivars from different sources, sixteen NAM parent lines (B73, CML103, CML228, CML247, CML277, CML322, CML333, CML69, Ki11, Ki3, Ky21, M37W, Mo18w, NC350, Oh43 and Tx303), four Korean hybrids (Cheongdaok, Gangdaok, Kwangpyeongok and Pyeonganok) and one Southeast Asian genotype (DK9955). Drought stress (DS) index was evaluated with leaf rolling score at seedling stage and ASI at silking date. The leaf rolling scoring of CML228, DK9955 and Ki11 were determined 1.28, 1.85, 1.86, respectively. However, M37W, Kwangpyeongok, B73 and NC350 were determined over the 3. ASI analysis revealed that CML228, CML103, Cheongdaok, NC350, B73, CML322, Kwangpyeongok and Ki11 are represented less than 5 days under DS and less than 3 days of difference between DS and well-watered (WW), but CML69, Ki3, Pyeonganok, M37W, Mo18w and Gangdaok were represented more than 10 days under DS and more than 8 days of difference between DS and WW. Multi-Dimensional Scaling (MDS) analysis determined CML228, Ki11, and CML322 were regarded as drought tolerance cultivars. Eventually, Ki11 showed genetic similarity with Korean cultivars by QTL analysis and MDS analysis. Ki11 has a potential for development of drought tolerance maize with Korean cultivars.

• Journal of Life Science
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• v.21 no.11
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• pp.1541-1548
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• 2011

This study was carried out to evaluate the effects of the addition of different levels of CFP (Cordyceps with fly pupa) on growth performance in broiler chickens. 400 broiler chicks (Ross 308, 1 day old) were sorted randomly into 4 treatment groups and fed experimental diets for 35 days. The treatment groups were divided into a control group not fed with CFP (T1), and treatment groups fed with CFP 2.0% (T2), CFP 3.5% (T3), and CFP 5.0% (T4). Although the broilers' weight gain and feed efficiency were significantly higher (p<0.05) in the T3 group throughout the entirety of the test period, no statistically significant differences were noted among the T1 and T2, T4 groups. Triglyceride in the blood, total cholesterol, and LDL-C were significantly lower in the CFP treatment groups than in the control group (p<0.05). The blood lipid reduction rate ranged from 5.32 to 10.63% for triglycerides, from 9.23 to 12.62% for total cholesterol, and from 44.67 to 53.81% for LDL-C in the CFP treatment groups relative to the control group. The abdominal fat weight ratio was reduced significantly in the CFP treatment groups (p<0.05) compared with the control group, with a reduction rate range of 17.67-21.68%. Broiler carcass weight, carcass rate, and ratios of breast muscle, skin and thigh muscle weights to carcass weight were significantly higher in the T3 group, and statistically significant differences were noted among the T1 and T2, T4 groups (p<0.05). Enteropathogenic E.coli and Salmonella were lower in the CFP treatment groups than in the control group, whereas the beneficial bacteria Bifidobacteria were significantly higher in the CFP treatment groups than in the control group (p<0.05). These findings suggest that the Cordyceps with fly pupa can improve the carcass characteristics and body weight gain in broiler chickens.

• Journal of the Korean Society of Food Science and Nutrition
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• v.34 no.7
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• pp.1082-1090
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• 2005

Jocheong was prepared by adding Lentinus edodes extract to improve its quality and to give some functional properties. Contents of crude protein, ash and crude lipid were similar to those of control, while carbohydrate content was decreased. Total mineral content were $1,916.03\~2,674.24mg/kg$ that was no difference between test samples. From HPLC determination of free sugars, Jocheong was found to contain maltose as the highest sugar, followed by glucose and fructose. In amino acid analysis, seventeen amino acid were identified and quantified. Glutamic acid in Jocheong was major amino acid. The major fatty acids in Jocheong $(0\%,\;control)$ were linoleic acid, palmitic acid, oleic acid, myristic acid and caproic acid. There was no significant differences in fatty acid composition, pH and reducing sugar content among the Jocheong samples. The viscosity and solid contents tended to decrease with the addition of Lentinus edodes extract. Increasing the ratio of mushroom extract in Jocheong tended to decrease the lightness, yellowness and redness in Hunter's color value. Although sensory value decreased with increasing Lentinus edodes extracts, use of mushroom extracts (7: 3; saccharification liquids: Lentinus edodes extracts) is recommended for making Jocheong.

• Journal of the Korean Society of Food Science and Nutrition
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• v.38 no.5
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• pp.618-625
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• 2009

The purposes of this study were to evaluate food safety knowledge and to assess home food safety performance of home-delivered meal service recipients. Two facilities providing home-delivered meal services for older adults were located in Seoul. A total of 120 service recipients were surveyed using an individual interview technique and 97 responses were used for data analysis. A statistical data analysis was completed using SPSS program (ver.14) for descriptive analysis, t-test, ANOVA, and correlation analysis. The majority of the participants were 70 years old or older and females. They perceived their health status as poor or very poor and took more than one kind of medicines. An average score of the food safety knowledge test was 11.48 based on 18 points (63.8%). The results revealed that the older adults knew the importance of hand washing but were not aware of when and how to wash hands. There was room to improve knowledge on cleaning and sanitizing fresh fruits and using wiping cloth. The knowledge score for each category was not significantly different by gender and age. The home food safety practices of the older adults was rated as 2.8 out of 4 points; the highest score was associated for proper food handling category and the lowest score was for cleaning and sanitizing. The worst performance was related to managing hand cuts and wounds (1.96). The total knowledge score and an average performance score were significantly correlated (p<0.01). Food safety education programs targeting the older adults who receive home-delivered meal services would improve the recipients' food safety knowledge and practices related to consumption of the meals at home. The programs should focus on not only improving food safety knowledge but also changing food safety practices.

• Korean Journal of Environmental Agriculture
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• v.16 no.4
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• pp.295-303
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• 1997

To investigate the transformation characteristics of nitrogen and carbon from cow manure compost amended in soil under different moisture conditions, dynamics of nitrogen and carbon were determined periodically for 15 weeks of aerobic incubation at room temperature during July${\sim}$November, 1996. Cow manure compost matured with mixing saw dust was amended with the 4 ratios (0, 2, 4, 6%(wt/wt)) in Ap horizon soil, which collected from green house in Yesan, Chungnam. Moisture was controlled with 0.2, 0.3, 0.4, and 0.5 of mass water conte nt (${\theta}$m) to air dried soil, and water loss was compensated at every sampling. During incubation, soil pH was decreased continuously, that was caused by hydrogen generated from nitrification of ammonium nitrogen. And pH became higher with inclining cow manure compost amendment and water treatment, that meaned the increase of mineralization of organic-N to $NH_4\;^+-N$. Total nitrogen was reduced with increasing water content, but total carbon showed the contrast tendency with that of nitrogen. Therefore, C/N ratio slightly decreased in the low water condition (${\theta}$m 0.2) during incubation, but increased continuously in high water condition over ${\theta}$m 0.4. As a result, it was assumed that soil fertility is able to be reduced in the high water content over available water content. Nitrate transformation rate increased lasting in the low water content less than ${\theta}$m 0.3. Itdropped significantly in the first $2{\sim}3$ weeks of incubation over ${\theta}$m 0.4. In particular, nitrate was not detected in ${\theta}$m 0.5 of water content after the first $2{\sim}3$ weeks. In contrast, ammonium transformation was inclined with increasing water treatment. Nitrogen mineralization rate, which calculated with percentage ratio of (the sum of ex.$NH_4\;^+-N$ and $NO_3\;^--N$)/total nitrogen, was continuously increased in the low water content of ${\theta}$m 0.2 and 0.3. But it saw the different patterns in high water content over ${\theta}$m 0.4 that was drastically declined in the initial stage and then gradually inclined . From the above results, nitrogen transformation patterns differentiated decisively in water content between ${\theta}$m 0.3 and 0.4 in soil. Thus, it is very important for the maintain of suitable soil water content to enhance fertility of soil amended with manure compost. However, excess treatment of manure compost might enhance the possibility of contamination of small watershed and ground water around agricultural area.

• Korean Journal of Environmental Biology
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• v.35 no.2
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• pp.116-122
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• 2017

Basic dyes such as malachite green and methylene blue have been used as disinfectants to control water fungal infections since the 1930s. However, after succeeding reports of carcinogenicity and bioaccumulation of the dye, their use was forbidden in lieu of public health. This study undertook to evaluate the therapeutic effect of sulfur solution processed by effective microorganisms (EM-PSS) against Saprolegnia parasitica infection, and its safety in fish. In vitro antifungal evaluation of EM-PSS inhibited the growth of S. parasitica mycelia at concentrations of 50 ppm or higher. The acute toxicity test of EM-PSS to the mud fish (Misgurnus mizolepis) measured a no effect concentration (NOEC) at 100 ppm, the lowest effect concentration (LOEC) at 125 ppm, and the half-lethal concentration ($LC_{50}$) at 125 ppm in juvenile and 250 ppm in the immature stage. In addition, the ecotoxicity test of EM-PSS using Daphnia magna inhibited swimming of D. magna at concentrations of 100 ppm or less. Lastly, the EM-PSS prevented infection of S. parasitica to mud fish, at concentrations of 50 ppm. Furthermore, at 100 ppm concentration, the EM-PSS showed no acute toxicity on mud fish, nor any eco-toxic effects on D. magnano. Therefore, we conclude that carcinogenic disinfectants such as malachite green and methylene blue could be replaced by EM-PSS to remove S. parasitica in mud fish farming, and might be a potential eco-friendly disinfectant in aquaculture.

• Journal of the East Asian Society of Dietary Life
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• v.17 no.6
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• pp.834-839
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• 2007

This study was designed to determine the optimal ratio of dropwort powder in castella by adding the powder at levels of 0, 3, 6, 9, and 12% respectively. The properties of the castella were analyzed by specific gravity, specific volume, color determinations, texture properties and sensory evaluation. The Specific gravity increased with increasing amount of dropwort powder. However, the specific volume decreased with increasing dropwort powder. For the color values, as more dropwort powder was added, the L-value decreased. The castella with 9% dropwort powder had a higher hardness, gumminess, and chewiness. A sensory panel perceived that the external and internal color of the castella become darker with the dropwort powder substitution and the grain size decreased with increasing amount dropwort powder, while sweet taste showed no significant difference. The order of overall preference was DP 9>DP 6>DP 12>CON>DP 3. Therefore, the substitution of 9% of wheat flour with dropwort powder was recommended in the production of castella.

• Journal of the Korean Society of Food Science and Nutrition
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• v.41 no.6
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• pp.861-869
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• 2012

This study was conducted to investigate the purchasing status and to compare supplier performance evaluations between competitive bidding and negotiated contracts in school foodservice in Changwon, Korea. A total of 190 questionnaires were distributed and 167 (return rate 87.9%) were collected from June 29 to September 28, 2010, and then a total of 151 (analysis rate 79.5%) were used for the final analysis. First, 91.4% of food product purchases for school meals were contracted through competitive bidding, especially limited competitive bidding. It mainly consisted of agricultural products, processed food, and eco-friendly agricultural products (fruit). Second, 78.8% of schools purchased food products by negotiated contracts, while single negotiation accounted for 59.7%. Food products by negotiated contract consisted of meat, kimchi, and fish. Third, the purchase status of competitive bidding and negotiated contracts showed a significant difference in agricultural products (p<0.001), fish (p<0.001), meats (p<0.001), poultry (p<0.001), antibiotic-free poultry (p<0.001), eco-friendly grain (p<0.001), eco-friendly agricultural products (fruit) (p<0.001), eco-friendly processed food (p<0.001), processed products (p<0.001), milk (p<0.001) and general grain (p<0.001) except for kimchi. Fourth, comparative analysis of supplier performance evaluation (on a 5-point Likert scale) of school foodservice showed that price of product of competitive bidding (3.73) was significantly higher than that of negotiated contract (2.95) (p<0.001), and the overall performance level of the negotiated contract (3.85) was significantly higher than that of competitive bidding (3.61) (p<0.01). The supplier performance evaluation levels of product packaging (p<0.01), product quality at the time of delivery (p<0.001), hygiene of products (p<0.001), consistency to specification (p<0.001), swiftness of return and exchange (p<0.001), emergency delivery (p<0.001), service of delivery staff (p<0.05), and handling of complaints (p<0.001) of negotiated contracts were significantly higher than those of competitive bidding of school foodservice. In conclusion, school foodservice selected food suppliers both by adopting competitive bidding and negotiated contracts. And there was a significant difference of school foodservice supplier performance between competitive bidding and negotiated contracts in Changwon, Korea.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.51 no.5
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• pp.408-419
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• 2006

A pot experiment was conducted for two years to evaluate the effects of purified Si fertilization combined with $^{15}N$ on the nutrient uptake, plant growth characteristics, and photosynthetic characteristics of rice in water melon cultivated soil. In 2002, plant height was positively affected at 25 DAT (Day After Transplanting) by Si fertilization in 100%N treatment. However, in 2003, plant height at 25 DAT was negatively affected by Si fertilization in low N level but it was reversed in high N level with initial increase of plant height. Tiller number per pot was positively affected by N and Si fertilization level, especially for high N fertilized treatment. Leaf color was positively affected by Si fertilizatlon in no N fertilized pots, however, Si was not effected in 50%N and 100%N fertilized treatments. N harvest index (NHI) increased with increased Si fertilization in no N plots, however it decreased with increasing of N fertilization level. Nitrogen use efficiency (NUE) decreased with increasing of fertilized N but Si fertilization increased NUE in 50%N plots, however, it was not different by the Si fertilization level in 100%N plots. In 50%N+200%Si plots, NUE was greatest with 130 and shoot N content was $16.2g-N/m^{2}$. N content ($g/m^{2}$) in rice plant increased with increasing Si fertilization in no N plots at panicle initiation stage, 50 and 100%N plots at heading stage and all N treatment at harvesting time. This was mostly more efficient in late growth stage than early growth stage. The concentration (%) of P and K increased with increasing N fertilization level at heading and harvesting but it was not significantly different by the Si fertilization treatment except a little decreasing with increasing Si fertilization level at heading. Potassium content was also not significantly related with N fertilization level except increasing with Si fertilization level at panicle initiation stage. Plant Ca content (%) decreased with increasing of Si fertilization at heading stage and Si fertilization increased Ca content at panicle initiation stage and heading stage and it increased with increasing of Si fertilization level. Photosynthetic activity was not directly related with Si fertilization amount, however, Fluorescent factors, Fv'/Fm' and PsII, were positively affected by Si fertilization level. In conclusion, N fertilization in Si 200% fertilized condition should be reduced by about 50% level of recommended N fertilization for rice cropping in green-house water-melon cultivated paddy field. However, improvement of Ps by Si fertilization could not be attributed to Ps activity in the same leaf area but because of increased total leaf area per pot improved fluorescent characteristics.

• Korean Journal of Soil Science and Fertilizer
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• v.32 no.3
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• pp.261-267
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• 1999

Pot experiments were conducted to evaluate the phosphorus (P) availability with cropping in soils where P were highly accumulated. Bray 1-P contents of the used three soils were 584, 695 and $1043P\;mg\;kg^{-1}$, respectively. Corn ${\rightarrow}$ Chinese cabbage ${\rightarrow}$ Chinese cabbage ${\rightarrow}$ corn were sequentially grown from 1996 to 1998. P fertilizer was applied at three levels of 0 (P0), recommended application rate (P1), and double of recommended application rate (P2). At the end of each crop growth, available P content was determined by methods of Bray 1-P, Olsen-P and Lancaster-P. The growth of crops were not significantly affected by the rates of P applications. The relative yields of PO treatment were more than 88% of P1 treatment. The recoveries of added phosphorus were relatively low due to the high content of available phosphorus in soils. Although available phosphorus contents decreased through cropping, the concentration of soil available phosphorus was maintained high level even after the final cropping. In the case of P0 treatment in the three soils, the residual concentration was in the range of $410{\sim}610mg\;kg^{-1}$ for Bray 1-P, $284{\sim}410mg\;kg^{-1}$ for Olsen-P and $368{\sim}524mg\;kg^{-1}$ for Lancaster-P. The amount of soil available phosphorus decreased during the experiments was linearly regressed with high significance to the amount of P taken up by crops. The regressions of soil 1 as follow, Bray 1-P : y=149.7x=102.7, Lancaster-P : y=209.2x-140.2, Olsen-P: y=60.8x=19.9. The decrease rate of available phosphorus in the P0 treatment with cropping was described by an equation of first-order chemical reaction. The equation of soil1 was as follow: Bray 1-P: In(C)= -0.12N + 6.96 r=-0.991, Lancaster-P: In(C)= -0.14N = 6.88 r= -0.938, Olsen-P: In(C)= -0.07N = 6.37 r= -0.959. The rate constants seemed to be affected by ply, sand and silt content, and exchangeable $Ca^{2+}$ concentration. The times of cropping needed to reduce the content of available P to half of the initial or to the index level could be predicted by using that equation.