• Korean Journal of Soil Science and Fertilizer
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• v.45 no.3
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• pp.377-384
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• 2012

This study was carried out to evaluate effect of temperature condition on nitrogen mineralization of organic matter, distribution of microbial group by PLFA profiles, and soil microbial community in non-volcanic ash soil. Dried soil 30 g mixed well each 2 g of pellet (OFPE) organic fertilizers, pig manure compost (PMC), and food waste compost (FWC). And then had incubated at $10^{\circ}C$, $20^{\circ}C$, and $30^{\circ}C$, respectively. Nitrogen mineralization rate increased with increasing temperature and that was in the order of FWC>OFPE>PMC. Distribution ratio of microbial group by PLFA profiles showed that was different significantly according to incubation temperature and the type of organic matter. As incubating time passed, density of microbial group decreased gradually. The Gram-bacteria PLFA/Gram+ bacteria PLFA, Fungi PLFA/Bacteria PLFA, and Unsaturated PLFA/saturated PLFA ratios were decreased according to the increasing temperature gradually. Principal component analysis using PLFA profiles showed that microbial community structures were composed differently by temperature factor at both 75 days ($10^{\circ}C$) and 270 days ($30^{\circ}C$). In conclusion, Soil microbial community structure showed relative sensitivity and seasonal changes as affected by temperature and organic matter type.

• Korean Journal of Soil Science and Fertilizer
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• v.45 no.4
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• pp.467-474
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• 2012

This study was carried out to evaluate effect of temperature condition on nitrogen mineralization of organic matter, distribution of microbial group by PLFA profiles, and soil microbial community structure in volcanic ash soil. Dried soil 30 g mixed well each 2 g of pellet (OFPE) organic fertilizers, pig manure compost (PMC), and food waste compost (FWC). And then had incubated at $10^{\circ}C$, $20^{\circ}C$, and $30^{\circ}C$, respectively. Nitrogen mineralization rate increased with increasing temperature and that was in the order of FWC>OFPE>PMC. Distribution ratio of microbial group by PLFA profiles were different significantly caused by incubation temperature and the type of organic matter. As incubating time passed, density of microbial group decreased gradually. The Gram-bacteria PLFA/Gram+ bacteria PLFA, Fungi PLFA/Bacteria PLFA, and Unsaturated PLFA/saturated PLFA ratios were decreased according to the increasing temperature gradually. But cy19:0/$18:1{\omega}7c$ ratio increased both FWC and PMC treatment. Principal component analysis using PLFA profiles showed that microbial community structure made up clearly at both 75 days ($10^{\circ}C$) and 270 days ($30^{\circ}C$) by temperature factor. As incubating time passed, microbial community structure shifted gradually.

• Korean Journal of Environmental Agriculture
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• v.35 no.1
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• pp.32-38
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• 2016

BACKGROUND: Our study aims to investigate the impact of temperature on the abundance and structure of soil microbial community in a temperature gradient tunnel.METHODS AND RESULTS: To investigate the interaction between temperature and input of C and N, rice straw and urea were applied to the study plots, respectively. We also studied the impact of plants by comparing plots cultivated with rice and unplanted plots. Soil microbial response was measured using the phospholipid fatty acid (PLFA) analysis. Soil chemical properties, including pH and ammonia and phosphate concentrations were influenced by warming and material addition. Microbial PLFA was partially influenced by material inputs, and actinomycetes PLFA was decreased by warming. In cultivated rice plots, an increase in the carbon to nitrogen ratio illustrated the effect of plant on microbiota caused by carbon addition through the root residues. Results from the principal component analysis of PLFA data showed that warmed and control plots applied with rice straw could be separated by principal component analysis.CONCLUSION: Our results suggest that plant influence both the microbial community structure and abundance, and temperature change has a minimal impact on soil microorganisms in flooded soil.

• The Korean Journal of Mycology
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• v.12 no.1
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• pp.35-43
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• 1984

To produce and characterize antineoplastic constituents in the submerged cultured­mycelia of Laccaria laccata, the mycelia were extracted with distilled water. Purification of the extract was carried out by acetone precipitation, by ion exchange chromatography using DEAE­Sephadex A-50, CM-Sephadex C-25 resins, and by gel filtration chromatography on Sephadex G-200. Each fraction obtained during the purification was examined for antineoplastic activity against sarcoma 180 in ICR mice. As the purification proceeded, the antineoplastic activity was markedly increased. The highly purified Fraction E showed 75% tumor inhibition ratio at a dose of 10mg/kg/day and contained 81% polysaccharide and 4% protein. The antitumor component of Fraction E stimulated an accumulation of peritoneal exudate cells including peritoneal macrophages, and is named laccaran.

• Korean Journal of Soil Science and Fertilizer
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• v.44 no.2
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• pp.236-241
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• 2011

Soil microbial diversity was responsible for a strong effect on the chemical properties of orchard soils. This study evaluated a relationship between soil chemical properties and soil microbial diversities at 25 sites in orchard soils in Gyeongnam Province. The average nutrients in the orchard soils were 2.6 times for available phosphorous, 2.3 times for exchangeable potassium and 1.3 times for exchangeable calcium higher compared to recommend concentrations in the orchard soils. Contents of available phosphorous and organic matter in the inclined piedmont soils were higher than those in the other topographical soils (p<0.05). Populations of fungi and fluorescence Pseudomonas sp. in the silt loam soils were significantly higher than those in the sandy loam soils (p<0.05). In principal component analysis of chemical properties and microbial populations in the upland soils, our findings suggested that population of bacteria should be considered as potential factor responsible for the clear orchard soils differentiation. The soil organic matter was significantly negative correlation with population of bacteria whereas was positive correlation with population of fungi in orchard soils.

• Asian-Australasian Journal of Animal Sciences
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• v.27 no.6
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• pp.898-906
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• 2014

The objective of this study was to investigate differences in the faecal microbial composition among Lantang, Bama, Erhualian, Meishan, Xiaomeishan, Duroc, Landrace, and Yorkshire sows and to explore the possible link of the pig breed with the gut microbial community. Among the sows, the Meishan, Landrace, Duroc, and Yorkshire sows were from the same breeding farm with the same feed. Fresh faeces were collected from three sows of each purebred breed for microbiota analysis and volatile fatty acid (VFA) determination. Denaturing gradient gel electrophoresis (DGGE) analysis revealed that samples from Bama, Erhualian, and Xiaomeishan sows, which from different farms, were generally grouped in one cluster, with similarity higher than 67.2%, and those from Duroc, Landrace, and Yorkshire sows were grouped in another cluster. Principal component analysis of the DGGE profile showed that samples from the foreign breeds and the samples from the Chinese indigenous breeds were scattered in two different groups, irrespective of the farm origin. Faecal VFA concentrations were significantly affected by the pig breed. The proportion of acetate was higher in the Bama sows than in the other breeds. The real-time PCR analysis showed that 16S rRNA gene copies of total bacteria, Firmicutes and Bacteroidetes were significantly higher in the Bama sows compared to Xiaomeishan and Duroc sows. Both Meishan and Erhualian sows had higher numbers of total bacteria, Firmicutes, Bacteroidetes and sulphate-reducing bacteria as compared to Duroc sows. The results suggest that the pig breed affects the composition of gut microbiota. The microbial composition is different with different breeds, especially between overseas breeds (lean type) and Chinese breeds (relatively obese type).

• The Plant Pathology Journal
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• v.39 no.2
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• pp.207-219
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• 2023

Soft rot is a widespread, catastrophic disease caused by Pectobacterium carotovorum subsp. carotovorum (Pcc) that severely damages the production of Amorphophallus spp. This study evaluated the rhizosphere bacterial and fungal communities in Pcc-infected and uninfected plants of two species of Amorphophallus, A. muelleri and A. konjac. Principal component analysis showed that the samples formed different clusters according to the Pcc infection status, indicating that Pcc infection can cause a large number of changes in the bacterial and fungal communities in the Amorphophallus spp. rhizosphere soil. However, the response mechanisms of A. muelleri and A. konjac are different. There was little difference in the overall microbial species composition among the four treatments, but the relative abundances of core microbiome members were significantly different. The relative abundances of Actinobacteria, Chloroflexi, Acidobacteria, Firmicutes, Bacillus, and Lysobacter were lower in infected A. konjac plants than in healthy plants; in contrast, those of infected A. muelleri plants were higher than those in healthy plants. For fungi, the relative abundances of Ascomycota and Fusarium in the rhizosphere of infected A. konjac plants were significantly higher than those of healthy plants, but those of infected A. muelleri plants were lower than those of healthy plants. The relative abundance of beneficial Penicillium fungi was lower in infected A. konjac plants than in healthy plants, and that of infected A. muelleri plants was higher than that of healthy plants. These findings can provide theoretical references for further functional research and utilization of Amorphophallus spp. rhizosphere microbial communities in the future.

• Journal of Microbiology and Biotechnology
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• v.34 no.4
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• pp.863-870
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• 2024

Meju, a fermented soybean brick, is a key component in soybean foods like doenjang and ganjang, harboring a variety of microorganisms, including bacteria and fungi. These microorganisms significantly contribute to the nutritional and sensory characteristics of doenjang and ganjang. Amplicon-based next-generation sequencing was applied to investigate how the microbial communities of meju fermented at low and high temperatures differ and how this variation affects the microbial communities of doenjang, a subsequently fermented soybean food. Our metagenomic data showed distinct patterns depending on the fermentation temperature. The microbial abundance in the bacterial community was increased under both temperatures during the fermentation of meju and doenjang. Weissella was the most abundant genus before the fermentation of meju, however, it was replaced by Bacillus at high temperature-fermented meju and lactic acid bacteria such as Weissella and Latilactobacillus at low temperature-fermented meju. Leuconostoc, Logiolactobacillus, and Tetragenococcus gradually took over the dominant role during the fermentation process of doenjang, replacing the previous dominant microorganisms. Mucor was dominant in the fungal community before and after meju fermentation, whereas Debaryomyces was dominant under both temperatures during doenjang fermentation. The dominant fungal genus of doenjang was not affected regardless of the fermentation temperature of meju. Strong correlations were shown for specific bacteria and fungi linked to specific fermentation temperatures. This study helps our understanding of meju fermentation process at different fermentation temperatures and highlights different bacteria and fungi associated with specific fermentation periods which may influence the nutritional and organoleptic properties of the final fermented soybean foods doenjang.

• 제어로봇시스템학회:학술대회논문집
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• 2001.10a
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• pp.97.1-97
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• 2001

One of the main problems to constitute control method on biologically oriented wastewater purification processes, e.g. activated sludge process, sequential batch reactor, rotating bio-disk contactor, etc. is that it is hard to control the target component directly. For instance, while biochemical oxygen demand, suspended solids, and chemical oxygen demand are the key components to check the process performance, one may not control them directly since they are the results of microbial activities related to numerous physiochemical factors. Therefore controllers for bioprocess should be designed to make favorable condition for microorganisms´ living, e.g. dissolved oxygen level favorable, mixed liquor suspended solids concentration suitable ...

• Journal of Plant Biotechnology
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• v.37 no.1
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• pp.47-56
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• 2010

Sea buckthorn (Hippophae rhamnoides L.) is deciduous shrubs in the genus Hippophae, mainly cultivated in Europe and Asia. Sea buckthorn berries have a high vitamin C, vitamin E, carotenoids, carbohydrates, protein, organic acids, dietary minerals, triterpenoids, polyphenolic acids and amino acids. Extracts of sea buckthorn berries have anti- obesity, anti-oxidantive, anti-microbial, anti-ulcerogenic, anti-diabetic and nutritional effects. Sea buckthorn used as a traditional medicine for the treatment of cough, aid digestion, invigorate blood circulation and alleviate pain. Extracts of sea buckthorn branches and leaves was administered to humans and animals to treat gastrointestinal distress in Mongolia. This paper briefly reviews the most relevant experimental data on the pharmacological effects and isolated component of sea buckthorn. And, we also describe the importance of sea buckthorn as the environmental-friendly crops.