• Journal of the Korean Society of Food Science and Nutrition
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• v.40 no.3
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• pp.475-479
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• 2011

Although the storage period of raw baechu cabbage could be 2 months at $0{\sim}2^{\circ}C$, 1 month was appropriate considering the quality of the baechu cabbage, waste ratio, and storage cost. The polyethylene container was the most efficient storage container among polypropylene box, polypropylene net and polyethylene container. pH of a brined baechu cabbage using raw baechu cabbage was 4.0~4.3 after 8 weeks and its total bacteria and lactic acid bacteria counts were $10^7$ cfu/g, and textural property (springiness) lower than 50% was at 8th week of storage at $0{\sim}2^{\circ}C$ and thus its storage period was limited to 8 weeks. When brined baechu cabbage was prepared by raw baechu cabbage stored for 1 month at $0{\sim}2^{\circ}C$, its pH, microorganism counts and springiness showed similar trends to the brined cabbage using raw baechu stored for 0 month. However, its rates of change were faster than the brined baechu cabbage using the raw baechu, and the storage period was limited to 6 weeks. Brined baechu cabbage using the raw cabbage stored for 2 months and its storage period was limited by about 4 weeks judging by its indicated quality characteristics.

• Development and Reproduction
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• v.11 no.3
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• pp.245-251
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• 2007

Vinclozolin(VCZ), a systemic dicarboximide fungicide, has been used in the control of diseases caused by microorganism of some species in fruits, vegatables and ornamental plants. Although VCZ itself is a very weak antagonist for androgen receptor binding, both melabolites M1 and M2 are effective antagonists. The present study was undertaken to examine whether prepubertal exposure to VCZ affects on the onset of puberty and the associated reproductive parameters such as hormone receptor expressions in female rats. VCZ(10 mg/kg/day) was administered daily from postnatal day 21(PND 21) through the day when the first vaginal opening(V.O.) was observed. Gross anatomy and weight of reproductive tissues were compared to test the VCZ's effects on the cell proliferation. Furthermore, histological studies were performed to assess the structural alterations in the tissues. To determine the transcriptional changes in progesterone receptor(PR), total RNAs were extracted and applied to the semi-quantitative reverse transcription polymerase chain reaction(RT-PCR). As a result, delayed V.O. was shown in the VCZ group(PND $34.00{\pm}1.22$) compared to the control group(PND $38.20{\pm}1.92$; p<0.01). VCZ treatment significantly decreased the wet weight of ovaries and uteri compared to the control group(p<0.01). Graafian follicles and corpora lutea were observed only in the ovaries from the control animals, while numerous primary, secondary follicles and small atretic follicles were observed in the ovaries from VCZ group. Similarly, hypotrophy of luminal and glandular uterine epithelium was found in the VCZ group. In the semi-quantitative RT-PCR studies, the transcriptional activity of PR in ovary(p<0.01) from VCZ group were significantly lower than those from the control group while in uterus were similar compared with the control group. The present studies demonstrated that the acute exposure to VCZ during the critical period of prepubertal stage could inactivate the reproductive system resulting delayed puberty in female rats.

• Korean Journal of Ecology and Environment
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• v.46 no.2
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• pp.276-288
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• 2013

The present study investigates the effects of elevated soil nitrogen on growth and decomposition of Oryza sativa shoots. The plants were cultivated in greenhouse until leaf senescence and the total biomass of the plant increased 1.9 times at nitrogen addition plot. Total C and N content in shoot increased; however, lignin, C/N, and lignin/N levels decreased in the N-treated soil. The shoot litters collected from the control and N-treated soil were tested for decay and microbial biomass, $CO_2$ evolution, and enzyme activities during decomposition on the control and N-treated soil at $25^{\circ}C$ microcosm. The remaining mass of the shoot litter was approximately 6% higher in the litter collected from the control soil (53.0%) than the litter collected from high N-treated soil (47.1%). However, the high N-containing litter exhibited faster decay in the control soil than in the N-treated soil. The litter containing high N, low C/N, and low lignin/N showed a higher decomposition rate than that of low quality litter. The N-addition showed decreased microbial biomass C and dehydrogenase activity in soil; however, it exhibited high microbial biomass N and urease activity in soil. When the high N-containing litter decays on the N-treated soil, the microbial biomass C increased rapidly at the initial phase of decomposition and decreased thereafter, and dehydrogenase activity was less that of other treatment; however, there was no effect on the microbial biomass N. The urease in the decomposing litter was highest during the early decomposition stage and dramatically decreased thereafter. The present findings suggested that the N-addition increased N content in litter, but inhibited the decomposition process of above-ground biomass in terrestrial ecosystems.

• Korean Journal of Microbiology
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• v.50 no.4
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• pp.345-350
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• 2014

The aim of this study was to investigate the effect of high temperature on the viability of probiotic organisms (Bacillus subtilis, Lactobacillus plantarum, and Saccharomyces cerevisiae) mixed with animal feed under controlled conditions by simulating a farm feed bin in the summer. Following inoculation of probiotics into the feed, the pH and probiotic viability were monitored during an 8-day incubation at room temperature. Sterile and non-sterile feeds displayed different patterns of pH changes, with increased pH in non-sterile feed at 2 days, but a pattern of decreasing pH at 4 days. The viabilities of S. cerevisiae and B. subtilis after mono/co-inoculation were maintained without substantial changes during the incubation, whereas L. plantarum viability tended to decline. In both non-sterile and sterile feeds, the probiotics were maintained or grew without any antagonistic effects. Probiotic viability was also tested upon a shift to high temperature ($60^{\circ}C$). There was no distinct change in pH between sterile and non-sterile feeds after the temperature shift. L. plantarum and S. cerevisiae could not survive at the high temperature, whereas B. subtilis displayed normal growth, and it inhibited the growth of contaminant microbes. Fungal growth was not observed in non-sterile feed 2 days after supplementation with B. subtilis. Therefore, heat resistant B. subtilis could be safely used in feed bins to inhibit microbial contamination, even at high temperatures. The prevention of elevated temperature in feed bins is necessary for the utilization of L. plantarum and S. cerevisiae during the summer season.

• Journal of Animal Science and Technology
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• v.51 no.3
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• pp.207-216
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• 2009

This experiment was conducted to investigate the effects of dietary supplementation of organic acid mixture on growth performance, cecal microflora, blood characteristics and immune response in broiler chicks and to prove the possibility of organic acid mixture as an alternative to antibiotics growth promotor. A total of four hundred eighty, 1-day-old male broiler chicks (Ross$\times$Ross 308) were randomly divided into 4 groups with 4 replicates of 30 birds each. The treatments were NC (free antibiotics), PC (basal diet with virginiamycin 10 ppm and salinomycin 60 ppm), 0.3% organic acid, and 0.5% organic acid. The final body weight and body weight gain were significantly higher in organic acid 0.5% than NC (P<0.05). The feed conversion ratio in all treated groups were significantly improved as compared to that of NC (P<0.05). The carcass rate and relative organs weight were not significantly difference among the groups. The relative weight and length of small intestine in PC were significantly decreased than the other groups. The numbers of cecal coliform bacteria and Salmonella in all treated groups were significantly lower than NC (P<0.05). The number of cecal lactic acid bacteria was not different among the groups. No significant differences among the groups were observed in the contents of total cholesterol, triglyceride, blood urea nitrogen (BUN), albumin, aspartate aminotransferase (AST), and alanine aminotransferase (ALT) in blood serum. The contents of total protein and globulin in blood serum of PC and organic acid treated groups were significantly increased as compared to those of NC (P<0.05). Therefore, albumin:globulin ratio of PC and organic acid treated groups was significantly lower than NC (P<0.05). The total white blood cell (WBC), heterophil, lymphocyte, and stress indicator (heterophil:lymphocyte ratio) were not significantly different among the groups. No significant difference was observed on the expression rate of splenic cytokines mRNA in organic acid treated groups compared to the control. Consequently, supplemental organic acid mixture improved the growth performance, and influenced positive effects on the intestinal microflora by inhibiting the growth of harmful bacteria without any adverse effects on relative weights of organs and blood biochemical parameters in broiler chicks.

• Korean Journal of Soil Science and Fertilizer
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• v.33 no.1
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• pp.52-60
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• 2000

This study was conducted to gain basic data for alleviation of gas emission and conservation of healthy soil environment by investigating an aspect of gas emission and microbial diversity due to the supplement of different fertilizers after application with a livestock manure compost in greenhouse soils. Green pepper was cultivated in clay loamy soil from April to August. Before planting, a livestock manure compost was applied with $741mg\;ha^{-1}$ on the basis of the phosphate content contained in compost. And then, deficient nitrogen for cropping was supplemented with either quick-acting fertilizer of urea or a controlled slow release fertilizer made from urea formaldehyde(U/F). $NH_3$ and R $NH_2$ gases emitted from soil showed a low concentration in the early stage but a maximum in 27 days after planting, then decreased rapidly and not detected after 33 days. Their average concentrations were 42% and 85% lower in the treatment of slow release fertilizer than that of urea fertilizer, respectively. $CO_2$ gas emitted under urea fertilization was ranged from 1,200 to $3,200mg{\ell}^{-1}$ and that in slow release fertilizer was $900{\sim}2,650mg\;{\ell}^{-1}$. The average concentration of urea treatment was $2,260mg{\ell}^{-1}$ and 30% higher than that of slow release fertilizer. The treatment of slow release fertilizer with the lapse of cropping time populated larger in numbers of bacteria, actinomycetes, nitrate bacteria and nitrate reduction bacteria, and ratios of bacteria and actinmycetes to fungi than that of urea fertilizer. But the number of fungi was higher in the treatment of urea fertilizer and denitrifying bacteria showed a similar trend in both treatments. The microbial diversity index, which calculated with numbers of 6 species of microorganisms, was decreased with increasing of growing stage in the range of 0.1 to 0.35 and that was higher in the tratment of slow release fertilizer than urea.

• Journal of The Korean Society of Grassland and Forage Science
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• v.41 no.1
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• pp.62-70
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• 2021

The purpose of this study was to determine the optimal digestible energy levels on pregnancy mares. Physical changes and fecal microorganism in pregnant horse and changes in birth characteristics of neonatal foals were investigated. The experiment was conducted by 18 mares (Jeju corssed bred, older than 36 months) into three treatment groups. The experimental diet consisted of 80%, 100%, 120% digestible energy levels based on NRC. The average daily intake was lower in the 120% (8.75±1.01) than the 100% (9.34±0.92), 80% (9.14±0.88) and there was significant difference (p<0.05). The feed efficiency was lower in the 120% than 80%, 100% (p<0.05). Total cholesterol, HDL-cholesterol, LDL-cholesterol and triglyceride was higher in 120% than others (p<0.05). However there were no health problem and there was no difference between the treatment groups in the birth characteristics of neonatal foals. At the phylum level, Fibrobactres was difference by digestible energy levels, 80% (8.53%) was higher than 100%, 120%. At the genus level, Bacteroides and Kineothrix increased in fecal proportions with increasing digestible energy levels (p<0.05). Fibrobacter showed higher composition at 80% than 100% and 120% (p<0.05).

• The Korean Journal of Food And Nutrition
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• v.26 no.4
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• pp.841-849
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• 2013

The aim of this study was to investigate the quality characteristics of Kimchi, prepared with seasoning fluid, vinegar, and mustard extract to inhibit the proliferation of microorganisms and extend the edible period during fermentation at $25^{\circ}C$. We also added perilla leaf, endive, and mustard leaf to Kimchi to improve the flavor. The pH of control Kimchi fluid over 1 day after Kimchi processing, was $5.40{\pm}0.01$ and that of the experimental groups in which vinegar and mustard extract were added was $4.51{\pm}0.01{\sim}4.52{\pm}0.01$, which was lower than that of the control. As the fermentation progresses, the pH of the control decreased rapidly and that of the experimental groups decreased slowly. The initial titratible acidity of the control was low and 3 days later reached $0.95{\pm}0.04$. However, that of the experimental groups was $0.42{\pm}0.01{\sim}0.43{\pm}0.02$ and 5 days later reached a level similar to that of the control. The salinities of the Kimchi juice of both the control and the experimental groups were $2.67{\pm}0.06{\sim}2.80{\pm}0.10$% after 1 day and decreased during fermentation. The amount of lactic acid bacteria of the control was $8.17{\pm}4.01{\times}10^8cfu/g$, 1 day after the Kimchi processing and that of the experimental groups was $2.70{\pm}2.08{\times}10^7{\sim}3.63{\pm}2.80{\times}10^7cfu/g$. After 3 days, these were $3.13{\pm}1.94{\times}10^{11}cfu/g$ and $2.47{\pm}2.23{\times}10^9{\sim}8.03{\pm}3.71{\times}10^9cfu/g$, respectively. According to the result of sensory evaluation, throughout the entire period of the experiment, all sensory items such as color, odor, taste, texture, and total acceptability of the experimental groups were better than those of the control group (p<0.05). Especially, Kimchi in which perilla leaf was added was the best. With the addition of vinegar and mustard extract to the Kimchi, microorganism proliferation was inhibited and the edible period was extended. The minerals, vitamins and antioxidants of leaf vegetables could therefore be obtained.

• Journal of Korean Society of Environmental Engineers
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• v.29 no.2
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• pp.184-191
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• 2007

Coal-, coconut- and wood-based activated carbons and anthracite were tested for an adsorption and biodegradation performances of nitrogenous chlorinated by-products such as chloropicrin, DCAN, DBAN and TCAN. In early stage of operations, an adsorption performance was a main mechanism for removal of nitrogenous chlorinated by-products, however as increasing populations of attached bacteria, the bacteria played a major role in removing nitrogenous chlorinated by-products in the activated carbon and anthracite biofilter. It was also investigated that the compounds were readily subjected to biodegrade. Whilst the coal- and coconut-based activated carbons were found most effective in adsorption of the compounds, the anthracite was worst in adsorption of the compounds. Highest populations and activity of attached bacteria were shown in the coal-based activated carbon. The populations and activity of attached bacteria decreased in the order: coconut-based activated carbon > wood-based activated carbon > anthracite. The attached bacteria were inhibited for removal of the compounds at temperatures below $10^{\circ}C$. The attached bacteria were more active at higher water temperatures$(20^{\circ}C\;<)$ but less active at love. water temperature$(10^{\circ}C\;>)$. The removal efficiencies of the compounds obtained using coal-, coconut- and wood-based activated carbons and anthracite were directly related to the water temperatures. In particular, water temperature was the most important factor for removal of the compounds in the anthracite biofilter because the removal of the compounds depended mainly on biodegradation. Therefore, the main removal mechanism of the compounds the main mechanism on the removal of the compounds using activated carbon was both adsorption and biodegradation by the attached bacteria. The observation suggests that using coal-based activated carbon is the best for removal of nitrogenous chlorinated by-products in the water treatment.

• Applied Biological Chemistry
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• v.48 no.4
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• pp.322-325
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• 2005

Pseudomonas sp. JH1014 was isolated from stream water as a detergent-compatible alkaline protease producing microorganism. The strain produced no detectable cellulolytic activity in LB medium. The addition of carboxymethyl cellulose induced the production of carboxymethyl cellulase (CMCase) without causing any significant change in the growth pattern of the strain. The strain reached its maximum growth after 9 to 12 h at $37^{\circ}C$, and the production of CMCase in the presence of the substrate reached its maximum after 21 h of growth at $37^{\circ}C$. The optimum pH of the crude enzyme preparation was pH 6.0. The enzyme had an optimal temperature at $55^{\circ}C$, and retained 70% of its original activity when preincubated at $70^{\circ}C$ for 10 min. Activity staining of the crude enzyme preparation separated on an SDS-PAGE gel showed two active bands with molecular masses of 54 and 30 kDa, indicating that Pseudomonas sp. JH1014 produced at least 2 kinds of CMCase.