• Journal of the Korea Organic Resources Recycling Association
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• v.27 no.3
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• pp.63-74
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• 2019

This study carried out a human risk assessment of Cu, Pb, Zn and Ni contained in soil contaminated by improperly buried heavy metal wastes in railway sites. The purpose of the human risk assessment is to derive the need for soil remediation and factors that should be considered during soil remediation. Risk assessment was performed in accordance with the Environment Ministry's Risk Assessment Guidelines. The results of the human risk assessment of contaminated heavy metal soil contaminated by improperly buried waste in the railway site were presented after the process of determining exposure concentration, calculating exposure, and determining carcinogenic hazards. The heavy metal content of soil is 621.3 Cu mg/kg, 2,824.5 Pb mg/kg, 1,559.1 Zn mg/kg and 45 Ni mg/kg, which is the exposure concentration of the target contaminant. The results of human exposure according to exposure pathways were high in the order of soil outdoor dust >soil ingestion >soil contact, and Pb >Zn >Cu >Ni were higher in order of contaminant. The carcinogenic and noncarcinogenic risks of soil contaminated with heavy metal waste were higher than the allowable carcinogenic risks (TCR> $10^{-6}$) and the risk index (Hi < 1.0) suggested by USEPA. Therefore, the site needs to be remediated.

• Journal of Life Science
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• v.32 no.4
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• pp.290-297
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• 2022

This study was performed to investigate the organic acids, alcohol metabolism enzyme, and antioxidative, nitrite-scavenging, and hepatoprotective effects of Dendropanax morbifera vinegar prepared by a traditional fermentation method. Among the organic acids detected, acetic acid was the highest found, at 91.72 mg/ml, followed by lactic acid (7.31 mg/ml), malic acid (1.36 mg/ml), and succinic acid (1.20 mg/ml). The total polyphenol content of the D. morbifera vinegar was 13.73 ㎍ tannic acid equivalent (TAE)/ml. The 1,1-Diphenyl-2-picrylhydrazy (DPPH) radical scavenging activity of D. morbifera vinegar was 76.04% at a 60% concentration. The superoxide dismutase (SOD) activity of D. morbifera vinegar was increased in a dose-dependent manner, which was 95.14% at a 60% concentration, while the α-glucosidase inhibitory activity of D. morbifera vinegar was 98.94% at a 10% concentration. The effects of D. morbifera vinegar on alcohol metabolism were determined by measuring the generation of reduced nicotinamide adenine dinucleotide (NADH) by alcohol dehydrogenase (ADH) and acetaldehyde dehydrogenase (ALDH). The ADH and ALDH activities of D. morbifera vinegar were increased in a dose-dependent manner, 43.62% and 60.39% at a 60% concentration, respectively. The D. morbifera vinegar showed significant protective effects against tacrine-induced cytotoxicity in HepG2 cells at the 0.6% concentration. These results suggest that D. morbifera vinegar has great potential as a resource for high quality functional health beverages.

• Korean Journal of Organic Agriculture
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• v.30 no.2
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• pp.279-290
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• 2022

This study was conducted to find out that winter green manure crops could be efficient replacements of expeller cake fertilizers, which were mostly imported, on environment-friendly red pepper production. Four treatments were compared under the condition of plastic film house: 1) barley (B); 2) hairy vetch (HV); 3) mixtures of barley and hairy vetch (B/HV); 4) expeller cake (EC). Total nitrogen content in hariy vetch was 3.6%, which was higher than 1.5~1.8% in barley and mixtures of barley and hairy vetch. P₂O₅ and K₂O contents were similar in all green manures. Supplying amount of nitrogen from B, HV and B/HV plot, which were 172 kg ha^-1, 193 kg ha^-1, and 198 kg ha^-1, were higher than amount of basal nitrogen required by soil testing but were lower than that of total nitrogen, respectively. Among the green manure crops, C/N ratio of HV was the lowest at 11.8, showing a similar value to that of expeller cake, but that of B was the highest at 30.6. Total yield was no significant difference in all treatment plots although B/HV plot showed the highest yield, but initial yield in B plot with high C/N ratio was lower than that in EC plot.

• Journal of the Korea Organic Resources Recycling Association
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• v.29 no.4
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• pp.33-40
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• 2021

In this study, the physico-chemical and biological characteristics of anaerobic granular sludge at different heights of a full-scale UASB reactor (UASBr) were investigated. Granular sludge was taken from 1 m, 2 m, and 3 m above the ground level in the UASBr. The morphological analysis showed that the upper part had bigger granules and the lower part had rounder granules. The ANOVA test confirmed that the mean size and the roundness of the granules had statistically significant difference along the height at 95% confidence level, and there was a significant negative linear relationship between the size and roundness (r=-0.40, p<0.05). A SMA test using acetic, propionic and butyric acids showed that granules from 2 m height had the highest specific methanogenic activity. The EPS contents were also unequal to each height, with 2 m showing the highest content. These findings could be helpful to understand the different characteristics of stratified anaerobic granules in full-scale UASBr and maintain the reactor performance.

• Korean Journal of Organic Agriculture
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• v.29 no.4
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• pp.613-623
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• 2021

This study was conducted to investigate the effect of addition levels of coffee and green tea by products extract including polyphenols through hot water extraction on rumen fermentation. The treatment groups consisted of coffee extract (CO), green tea extract (GR) and mixed extract (MIX), and the addition level was 10 µL, 20 µL and 30 µL of three levels. The experiment consisted of a total of 10 experimental groups including the control group, and a full factorial design was used. The effect of polyphenol addition in coffee and green tea by-products was analyzed through main and interaction effect of statistical analysis. The total polyphenol content of the extracts was 106.15, 79.10 and 185.25 ㎍ GAE/g DM for coffee by-product, green tea by-product and mixture, respectively. Total gas production was significantly lower in the treatment groups than in the control (114.00 mL/gDM) (p<0.05). Methane emission tended to decrease as the polyphenol addition level increased. Moreover, the MIX showed the lowest methane emission when 30 µL was added (p<0.05). Volatile fatty acids showed a significant difference compared to the treatment group as a control (98.06 mM) (p<0.05), but there was no change according to the level of polyphenols. As a result of the main effect and interaction, it is thought that the effect on methane reduction and improvement of rumen fermentation in MIX20 can be expected. In a series of studies, the addition of 20 µL of a blended extract of coffee and green tea by-products is thought to reduce methane to levels that do not inhibit rumen fermentation.

• Korean Journal of Environment and Ecology
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• v.36 no.4
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• pp.422-432
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• 2022

Soil and micro-climatic environmental monitoring was conducted to evaluate the factors causing tree growth impediments at the Baekdudaegan ecological axis restoration project site. As a result, it was found that the nutrient supply was insufficient in the restoration project site due to the lack of organic matter, total nitrogen and cation exchange capacity of the soil compared to the surrounding forest. After the completion of the restoration, the soil moisture in the autumn decreased more than 7 times faster than that of the surrounding forest, and it was evaluated that the soil moisture was significantly low due to the lack of silt and clay content. In the case of the restoration site, the annual potential evapotranspiration was analyzed to be 975mm, which is approximately two times higher than that of the surrounding forest. The soil moisture of the restoration site in the summer decreased rapidly during the daytime when the amount of insolation increased and this was found to be strongly influenced by the increase in potential evapotranspiration. In order to improve the above factors affecting the tree growth at the Baekdudaegan ecological axis restoration project site, it is necessary to induce the smooth supply of nutrients and water to plants by improving physical proprieties and cation exchange capacity, i.e., using litterfall, humus soil, soil conditioner and organic fertilizer. The results of this study are expected to serve as basic data for the design, construction, and management of ecological axis restoration projects in the future.

• Animal Bioscience
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• v.36 no.3
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• pp.484-491
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• 2023

Objective: The aim of this trial was to investigate the effect of supplementation and withdrawal of selenium-enriched kale sprouts (SeKS) on productivity and egg Se concentration of laying hens. Selenium from commercial Se-enriched yeast (SeY) was used as a comparative Se source. Methods: One-hundred and eighty 61-week-old laying hens were randomly divided into 5 treatment groups with 4 replicates (9 hens each) in a 2×2+1 Augmented Factorial Experiment in a completely randomized design. The experimental diets were basal diet, basal diet supplemented with 0.2 and 0.4 mg Se/kg from SeKS and SeY, respectively. The 8-week feeding trial was divided into 2 periods, namely the Se supplemental period (week 1 to 4) and the Se withdrawal period (week 5 to 8). Results: Productive performance, egg quality and egg Se concentration of laying hens were not affected by sources of Se (SeKS and SeY) during both, the Se supplemental and withdrawal periods. Egg production and egg Se concentration increased (p<0.05) with increasing levels of Se supplementation. The egg Se concentration increased and reached a peak 1 week after Se supplementation. However, concentration of Se in eggs of hens fed Se from both sources decreased rapidly from the second week of the Se withdrawal period to reach the same egg Se concentration of hens fed the basal diet by the fourth week of the Se withdrawal period. Conclusion: The efficacy of Se from SeKS on productivity and egg Se concentration in laying hens was comparable to commercial SeY. Thus, SeKS can provide an alternate organic Se source for production of Se-enriched eggs.

• Journal of Wetlands Research
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• v.25 no.2
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• pp.132-144
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• 2023

The use of constructed wetlands (CWs) to sequester carbon has been a topic of interest in recent studies. However, CWs have been found to be both carbon sinks and carbon sources, thus leaving uncertainties about their role in carbon neutrality initiatives. To address the uncertainties, a bibliometric and comprehensive review on carbon sequestration in CWs was conducted. Upon forming various scripts using CorText Manager, it was found that a majority of the studies focused on the effectiveness of CWs to remove nutrients, particularly nitrogen. The results of the comprehensive review revealed that high carbon concentrations and carbon sequestration rates in CW soils are dependent on the vegetation types used, the ages of the CWs, and the organic content of inflow water entering the CWs. The Typha genus was the most dominant plant genus used in the CWs from the reviewed studies and was associated with the highest carbon sequestration rates documented in this review study. Furthermore, the relatively high ability of tree species, in comparison to emergent plants, to sequester carbon was observed. Therefore, incorporating tree species into CW designs and adding them to emergent plants is seen as a potential breakthrough approach to improve the ability of CWs to sequester carbon and ultimately contribute to mitigating climate change.

• Journal of Practical Agriculture & Fisheries Research
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• v.7 no.1
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• pp.64-73
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• 2005

This study was done to determine the regional adaptability of Dioscorea opposita in Korea. Suwon, Chunchon, Kangneung, Yonchon and Taean had soil pH of 6.62, 5.65, 5.9, 5.9 and 5.82, respectively, being at more unfavorable conditions than a standard soil condition for yam with pH 6.2. The amounts of organic matter in Suwon, Chunchon, Taean, and Yonchon were 1.96%, 4.51%, 3.76%, 1.89% and 1.12%, respectively, being at more favorable conditions than a standard organic matter in soil for yam with 2.0~3.0%. As the results from cultivating of large plantings in different regions, Suwon showed the largest the tuber dry weight of 135g. In comparison of general component between round yam and short yam in the area of Kangneung, protein of round yam(3.30%) was higher than that of short yam(1.40%). Dryness in round yam(36.5%) was lower than that of short yam(28.9%), indicating a higher dry weight ratio of round yam. In tuber extracts analysis, saponins content was respectively 23.7mg/g in round yam and 10.4mg/g in short yam.

• Journal of the Korea Convergence Society
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• v.13 no.1
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• pp.149-160
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• 2022

In this study, the physical quality and microbial changes of ginseng sprout according to the pretreatment process and packaging container were evaluated to improve the storage properties of ginseng sprout produced in smart farm. Quality change during storage (10 days) according to pretreatment method (ascorbic acid, citric acid, peroxyacetic acid) and packaging container (expanded polystyrene (EP), polypropylene (PP), polyethylene (PE), polypropylene + polyethylene + cast polypropylene (PP+PE+CPP)) was evaluated in terms of texture, viable cell count, water content, and color. As a result of comparison according to the type of pretreatment, the citric acid treatment group showed the lowest texture change and the effect on inhibition of bacterial growth. On the other hand, citric acid, which was most effective among pretreatments, was treated in all samples and then stored in 4 types of containers. Specially, the ginseng sprout in PP packaging container was not observed significant softening or color changes after 10 days storage, and the lowest changes in viable cell number. Therefore, this study was shown that citric acid treatment and use of PP packaging container are effective in increasing the shelf life of ginseng sprout.