• Korean Journal of Microbiology
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• v.35 no.4
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• pp.307-314
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• 1999

This study was aimed at the investigation of the possibility of the addition of lactic acid bacteria as "starter"for the preparation of radish juice. Forty strains of lactic acid bacteria were isolated from dongchimi that was fermented by a traditional method. The isolates were assorted into 5groups, Leuconostoc mesenteroides subsp. mesenteroides (J-9), Lacobacillus brevis (J-12), Lactobacillus fermentum (J-7), Lactobacillus sake (J-20), and Lactobacillus plantarum (J-39). Leuconostoc mesenteroides was predominated in the sample of dongchimi with frequency of 52.5%. Each of the strain, which exhibited the beat growth in the species, was selected in the 5species, and investigation of the fermentation characteristcis was carried out. The fermentation were performed for 9 days at 25${\circ}C$ after the inoculation of 0.3% ($10^{6}$ cfu/㎖) to each ultra-filtrated radish juice. The pH, total acidity, content of non-volatile organic acids were examined during the fermentation period. Lactobacillus plantarum showed the highest growth rate and the growth rate of Lactobacillus sake was the lowest. The pH (6.3-6.36) and total acidity (0.09-1.0 %) fo the ultrafiltrated radish juice before fermentation were changed to 3.2-4.3 and 0.65-1.2% after 9days, respectively. The changes of the pH and total acidity were related with the growth of the lactic acid bacteria; the better growth of lactic acid bacteria, the more rapid decrease of pH and increase of the total acidity. when the amount of non-volatile organic acids were estimated during fermentation, citric acid, malic acid, malonic acid, and succinic acid were decreased in all cases. However, the content of lactic acid increased with the progression of fermentation. L. mesenteroides (J-9), L. brevis (J-12) and L. fermentum (J-7) were chosen for the candidates of the starter for the lactic fermentation of radish juice based on the biochemical analysis and sensory evaluation.

• Journal of The Korean Society of Grassland and Forage Science
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• v.33 no.4
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• pp.257-262
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• 2013

This study investigates the effect of fermentable carbohydrate on the concentration of odorous compounds in pig slurry. Four types of pig diet were studied: control, peanut hull (crude fiber 29.87, NDF 44.02%), golden fiber (crude fiber 48.77, NDF 65.88%), and almond hull (crude fiber 44.30, NDF 64.44%). Pigs (average BW 37.0 kg) were fed diets that met the Korean Feeding Standard (2012) and their excreta samples were collected from the slurry pits. Levels of volatile organic compounds (phenols and indoles) and volatile fatty acids were analyzed by gas chromatography. Phenol level was the lowest (p<0.05) in golden fiber (33.26 ppm) group and the highest in control (97.29 ppm). The concentration of indoles in the peanut hull (1.27 ppm), almond hull (1.20 ppm), and golden fiber (1.02 ppm) groups was lower (p < 0.05) than that of control (1.79 ppm). Levels of short chain fatty acid (SCFA) were lower (p < 0.05) in golden fiber (1,319 ppm) and almond hull (1,433 ppm) groups than in control (1,893 ppm). Concentration of branched chain fatty acid (BCFA) in the golden fiber group (74 ppm) was lower (p < 0.05) than that of control (98 ppm). Taken together, the concentration levels of phenols, indoles, and VFAs decreased on addition of peanut hull, golden fiber or almond hull to the diet, suggesting that fermentable carbohydrate may contribute to reducing odorous compounds in pig slurry.

• Korean Journal of Organic Agriculture
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• v.23 no.2
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• pp.373-390
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• 2015

This study investigated the effect of coated feed using mixed oil on rumen fermentation characteristics. Two experiments were conducted based on materials that were mixed. First, cashew nut and soybean oils were mixed with white mineral oil. And second, different plant extracts were mixed with white mineral oil. At first experiment, inclusion levels of mixed oil on diet (0.03%, 0.1%, 0.5%) were applied as variables. A coated diet was fermented with rumen inoculum according to in vitro rumen fermentation and its parameters were investigated. In the result of first experiment, no negative effects on rumen pH were found. Significantly decreased dry matter digestibility was detected at 0.5% treatment (P<0.05). Total gas productions in control and 0.03% were significantly greater than those of others (P<0.05). Significantly reduced methane productions were found in all treatments compared to the control (P<0.05). Inclusion of mixed oil did not affect on ammonia production. Total volatile fatty acid production was also not influenced by coating with mixed oils. Rumen fermentation parameters were greatly changed according to introduced plant extracts at second experiment. The significantly lowest and greatest ammonia productions were found at treatments with Ixeris dentata and Plantago asiatica, respectively (P<0.05). The significantly greatest acetate and propionate productions were detected at treatments with Crucuma longa and Zizyphus vulgaris 1, respectively (P<0.05). All treatments, except Chrysanthemum idicum, Euyale ferox seed, Moringa leaf and fruit and Zizyphus vulgaris 1, showed significantly increased total volatile fatty acid production compared to the control (P<0.05). Only Paeonia lactiflora showed significantly lesser gas production than the control (P<0.05). In methane production, Ceramium, Zizyphus, Paeonia, Agrimonia, Torilis, Mugwort, Foeniculum, Euphorbia, Taraxacum, Artemisia, Momordica, Curcuma and Moringa reduced methane significantly compared to the control (P<0.05).

• Journal of Korean Society of Environmental Engineers
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• v.36 no.7
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• pp.469-475
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• 2014

The study investigated the physicochemical characteristics and the ecological risk of the Northport sediment in B city and the releasing properties of heavy metals into seawater during the resuspension also studied. The major components of the sediment are fine silt and clay which contains high organic matter and AVS (Acid volatile sulfide) and the ecological risk of the heavy metals in sediment also very high. The release rate of heavy metals into seawater was in order of Pb>>Cu>Cr>>Zn>Cd during the resuspension in a batch experiment, and the heavy metal release mainly attributed to the oxidation of metal sulfides. Heavy metals which came from easily oxidisable metal sulfides rapidly contaminated seawater within about 1.0 h of the sediment resuspension. The sulfide oxidation during the resuspension increased the residual fraction of heavy metals in the sediment, decreased the organic bound fraction, and changed the other fractions of heavy metals in the sediment. The release of heavy metals from the sediment during resuspension was affected by the resuspension time, the oxidation rate of metal sulfides and resuspended concentration of the sediment particle.

• Journal of the Korea Organic Resources Recycling Association
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• v.10 no.3
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• pp.59-67
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• 2002

This study was carried out to improve the utilization of food wastes known as major source of environmental pollution and to determine proper additional levels of methionine hydroxy analogue(MHA) on food wastes. 1%, 3% and 5% of MHA were added to 3 groups of food wastes gathered from small cafeteria. Each group has 3 reiteration. NaCl contents were tended to get higher as addition levels increased(p<0.05). And pH values were tended to get lower as additional levels increased(p<0.05). $NH_3-N$ contents were significantly decreased as additional levels increased(p<0.05). Total VFA(Volatile Fatty Acid) content was increased after 30 days of storage on control. On MHA treatments(1, 3, 5%), total VFA contents were decreased until 15 days of storage, and kept low values until the end of experiment. In terms of superficial change, mildew covered all over control, and covered by thin mildew on the surface of 1% MHA treatment. No superficial change found on 3% and 5% MHA treatments. In conclusion, over 1% addition of MHA was effective to prevent the decay and degeneration of food wastes.

• Korean Journal of Organic Agriculture
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• v.21 no.3
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• pp.437-450
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• 2013

Miscanthus sacchariflorus var. No. 1 has been newly developed in Korea. This study was conducted to assess the feed value of M. sacchariflorus var. No. 1 at different growth and harvesting time. Total 3 different miscanthus - 1y4m (first shoot and harvested at 4 month), 2y4m (second shoot and harvested at 4 month) and 2y8m (second shoot and harvested at 8 month). Two experiments were carried out, In vitro rumen simulated fermentation and In situ dry matter digestibility (DMD). Ruminal pH at in vitro fermentation were higher in M. sacchariflorus var. No. 1 treatments compared to the rice straw (RS). In volatile fatty acid production, 1y4m resulted in higher acetate production than the other M. sacchariflorus var. No. 1 at higher maturity stages. Significant differences among treatments were observed in propionate and total volatile fatty acid (VFA) productions at 9, 24 and 48 h of incubation times. Higher ammonia nitrogen productions were found as increased maturity of M. sacchariflorus var. No. 1. At In situ experiment, high DMD was detected in the order of RS (60.51%) > 1y4m (57.65%) > 2y4m (57.63%) > 2y8m (46.28%). The results from this study indicate that young and early harvested M. sacchariflorus var. No. 1 are able to improve its nutrient values in the ruminant animal.

• Journal of Wetlands Research
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• v.13 no.2
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• pp.243-263
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• 2011

In order to understand the sedimentary environment of the southern intertidal zone of Shihwa Lake, west coast of Gyeonggi-do, 10 surface and 2 core sediment samples were analysed for grain size, water content, AVS (Acid Volatile Sulfide), TOC (Total Organic Carbon), concentrations of metals (Al, Fe, Mn, Cu, As, Pb, Zn, Ni, Cd, and Cr). The surface sediments are generally poorly sorted (0.60~2.31 ${\phi}$) sandy Silt, slightly gravelly muddy Sand, silty Sand, Sand with mean grain size of 2.95 to 6.00 ${\phi}$. The sediments contain Al (1.54%), Fe (1.75%), Cu (9.1ppm), As (1.1ppm), Pb (18.8 ppm), Ni (11.0 ppm), Cd (0.02 ppm), and Cr (30.1 ppm) on the average. Heavy metals are concentrated less than ERL (Effect Range-Low), verified by NOAA (National Oceanic and Atmospheric Administration). In the core sediments, they are also less than the ERL. Based on the uniform vertical distribution of excess radioactivity of $^{210}Pb$, the core sediments seen to have been actively mixed biologically or rapidly deposited after the construction of Shi-Hwa Seawall. The 'enrichment factor' of metals, normalized to Al, shows that the upper sediments of 35 cm in depth are more polluted. infect was significant in 2 core sediment samples in 35 cm below layer.

• Korean Journal of Organic Agriculture
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• v.22 no.3
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• pp.491-502
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• 2014

The present study was conducted to investigate effective starter culture to improve biological activity of Asarum sieboldii. Antibacterial activity, antioxidant activity and reduction of enteric rumen methane production were used as criterions for biological activity. Ground A. sieboldii was added in MRS broth at 10% (w/v) and fermented by different starter cultures. Weissella confusa NJ28, Weissella cibaria NJ33, Lactobacillus curvatus NJ40, Lactobacillus brevis NJ42, Lactobacillus plantarum NJ45 and Lactobacillus sakei NJ48 were used for starter culture strains. Each starter culture was inoculated with 1% (v/v) ratio and fermentation was performed at $30^{\circ}C$ with agitation (150 rpm) for 48 h. MRS broth for the control was employed without starter culture. Then the fermentation growth was dried and extracted using ethyl alcohol. The growth of starter culture was detected at NJ40, NJ42, NJ45 and NJ48. And the highest cell growth was found in NJ40. Antibacterial activity against to Staphylococcus aureus, Listeria monocytogens, Mannheimia haemolytica and Salmonella gallinarum were observed in the extract fermented by NJ40 and NJ45. All treatments showed antioxidant activities, however, there were no significant differences (p>0.05). In in vitro rumen fermentation, negative control (NC) and positive control (PC) were assigned to without extract and with non-fermented A. sieboldii extract. Significant suppression of gas productions were detected in positive control and treatments compared to negative control (p<0.05). However, total volatile fatty acid production was not suppressed. Significant methane reduction per total volatile fatty acid productions were found in positive control and NJ45 treatment (p<0.05). The present study suggested a fermentation of A. sieboldii using NJ45 strain could improve its biological activity and make possible for its use in bio additive for enteric rumen methane mitigation without suppression of animal productivity.

• Korean Journal of Food Science and Technology
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• v.14 no.1
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• pp.6-10
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• 1982

To investigate the effect of organic acids on suppression of fishy odor, the change of the odor and the remaining amount of trimethyamine (TMA), selected as the representative component of fishy odor in clam pickle (15.5% NaCl) were examined by sensory evaluation and gas chromatography. The fishy odor linearly decreased as the amount of vinegar increased at ${\alpha}=0.01$, but there was no significant difference of fishness score for the changes of storage period and kinds of acid. Overall acceptability score was found to be the best when 8 ml vinegar added to 100g clam pickle. The remaining amount of TMA showed the tendency to decrease as the amount of acetic acid and storage time increased and kinds of acid were changed in order of acetic, malic and citric acid. However when $4\;{\mu}l/ml$ acetic acid (=8 ml vinegar/100g clam pickle) was added, the percentage of the remaining amount of TMA showed little decrease from about 95% for 72 hours of storage time. From the results of sensory evaluation and gas chromatography, it was considered that acids have the effect on suppression of fishy odor by producing non-volatile salts by combining with TMA chemically and that the effect of acids on suppression of fishy odor is mainly due to the masking effect at the concentration commonly used.

• Korean Journal of Food Science and Technology
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• v.20 no.4
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• pp.511-517
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• 1988

Kimchi, a traditional vegitable fermented food in Korea, was prepared and fermented at $5^{\circ}C$ in order to analyze the taste and flavor compounds. Major flavor components were identified as dimethyl-disulfide, dimethyl-trisulfide, dipropyl-disulfide, 1-butane 1-isothiocyanate, diallyl-disulfide by GC and GC/MS. Some organic acids such as lactic acid and citric acid increased from 1.2mg/100g and 5.4mg/100g in the initial stage to 33.3mg/100g and 44.4mg/100g at the end of fermentation, respectively. Free amino acids in kimchi were found to play an important role for the taste. The contents of total free amino acid increased from 316.3mg/100g to 600mg/100g in the fermented kimchi and glutamic acid, alanine, valine, leucine, lysine and arginine were abundant in kimchi. The results of sensory evaluation showed that the taste of kimchi was closely related to the contents of non-volatile organic acid, free amino acid and pH.