• Journal of agriculture & life science
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• v.50 no.1
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• pp.1-22
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• 2016

In this study, the securing state of nationally indicated beneficial microbial resources was evaluated in an aspect of bio-diversity using their taxonomical information. Depending on the analysis result with the Margalef's richness or the Mehinick's index which are representative bio-diversity analytical indices, species diversity values was revealed as 8.537, 3.546 within bacterial resources, 3.349, 2.167 within fungal resources. Several developed or researched beneficial strains and spoilage microbes showed relative taxonomical relationship with comparation of their biological information. As a result, we propose the necessity or countermeasure method for preventing the microbial spoilage with the overhauling consideration of advanced research on agricultural microbiology covering crop endophyte beneficial/spoilage microorganisms.

• Journal of Korean Society of Forest Science
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• v.83 no.2
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• pp.191-204
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• 1994

Due to its topographic complexities and various climatical condition, Korea exhibits diverse forest types. Dominant tree species in this zone are Quercus spp., Betula spp., Zelkova spp., Fraxinus spp., Pinus densiflora, Pinus koraiensis, and Pinus thunbergii ete. Genetic conservation in forest species in Korea there are three ways ; one is in situ, other is ex situ and third is in-facility conservation. In situ conservation include that are the present status of conservation of rare and endangered flora and ecosystem, the reserved forest, the national and provincial park, and the gene pool of natural forests. Ex situ conservation means to be established the new forest from in situ forest stands, progeny and provenance test populations, seed orchard and clone banks, and gene conservation in-facility. As a tool for low temperature storage, several aspects on in vitro system were studied ; (1) establishment of in vitro cultures from juvenile and/or rejuvenated tissues, (2) induction of multiple shoots from the individual micropropagules, (3) elongation of the proliferated shoots. Studies on cold storage for short-and long-term maintenance of in vitro cultures under $4^{\circ}C$ in the refrigerator were conducted. For the cryopreservation at $-196^{\circ}C$, various factors affecting survivability of the plant materials are being examined. The necessity of gene conservation of forest trees is enlarged not only to increase the adaptability for various environments but also to gain the breeding materials in the future. For effective gene conservation of forest trees, I would like to suggest followings ; 1. Forest stands reserved for other than the gene conservation purposes such as national parks should be investigated by botanical and gene-ecological studies for selecting bio-diversity and gene conservation stands. 2. Reserved forest for gene pool should be extented both economically important tree spp. and non-economical species. 3. Reserved forest for progeny test and clone bank should be systematically investigated for the use of Ex situ forest gene conservation. 4. We have to find out a new methodology of genetic analysis determining the proper and effective size of subpopulation for in situ gene conservation. 5. We should develop a new tree breeding systems for successful gene conservation and utilization of the genetic resources. 6. New method of in-facility gene conservation using advanced genetic engineering should be developed to save time and economic resources. 7. For the conservation of species with short-life span of seed or shortage of knowledge of seed physiology, tissue culture techniques will be played a great role for gene conservation of those species. 8. It is are very useful conservation not only of genes but of genotypes which were selected already by breeding program. 9. Institutional and administrative arrangements including legistlation must be necessarily taken for gene conservation of forest trees. 10. It is national problems for conservation of forest resources which have been rapidly destroyed because of degenerating environmental condition and of inexperienced management system of bio-diversity and gene conservation. 11. In order to international cooperation for exchanging data of bio-diversity and gene conservation, we should connect to international net works as soon as possible.

• Korean Journal of Plant Taxonomy
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• v.49 no.4
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• pp.324-333
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• 2019

Neutral genetic diversity found in plant species usually leaves an indelible footprint of historical events. Korea's main mountain range (referred to as the Baekdudaegan [BDDG]), is known to have served as a glacial refugium primarily for the boreal and temperate flora of northeastern Asia. In addition, life-history traits (life forms, geographic range, and breeding systems) influence the within- and among-population genetic diversity of seed plant species. For example, selfing species harbor significantly less within-population genetic variation than that of predominantly outcrossers. A previous study of two Liparis species (L. makinoana and L. kumokiri) emphasizes the role of the abovementioned factors shaping the levels of genetic diversity. Liparis makinoana, mainly occurring on the BDDG and self-incompatible, harbors high levels of within-population genetic diversity (expected heterozygosity, H_eP = 0.319), whereas there is no allozyme variation (H_eP = 0.000) in L. kumokiri, which is self-compatible and mainly occurs in lowland hilly areas. To determine if this trend is also found in other congeners, we sampled five populations of L. krameri from the southern part of the Korean Peninsula and investigated the allozyme-based genetic diversity at 15 putative loci. The somewhat intermediate levels of within-population genetic variation (H_eP = 0.145) found in L. krameri are most likely due to its occurrence in mountainous areas that, despite being outside of the main ridge of the BDDG, still served as refugia, and a self-incompatible breeding system. Management strategies are suggested for L. krameri and L. makinoana based on the levels and distribution of genetic diversity and inbreeding.

• Journal of Mushroom
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• v.19 no.3
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• pp.134-139
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• 2021

A diverse group of plant-growth promoting bacteria were isolated in button mushroom (Agaricus bisporus) media to investigate the plant-growth promoting traits of compounds including indole acetic acid (IAA), ammonia, 1-aminocyclopropane-1-carboxylic acid deaminase, siderophore, and hydrogen cyanide. Twenty-one bacterial strains showing positive effects for all the test traits were selected and classified to confirm bacterial diversity in the media habitat. Plant-growth promoting traits of the isolates were also assessed. All strains produced IAA ranging from 20 ㎍/mL to 250 ㎍/mL. Most of the isolates produced more than 80% siderophore. Four strains (Pantoea sp., PSB-08, Bacillus sp., PSB-13, Pseudomonas sp., PSB-17, and Enterobacter sp., PSB-21) showed outstanding performances for all the tested traits. In a bioassay of these four strains using mung bean plant, the best growth performances (23.16 cm, 22.98 cm, 2.27 g/plant, and 1.83 g/plant for shoot length, root length, shoot dry weight, and root dry weight, respectively) were obtained from the plants co-inoculated with Bacillus sp., PSB-13. The resultant data indicate that button mushroom media have got a diverse group of bacteria with plant growth promoting abilities. Thus, the media could be a good recycling resource for using to an effective bio-fertilizer.

• Steel and Composite Structures
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• v.44 no.1
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• pp.105-117
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• 2022

Impact resistance efficiency of the newly designed sandwich beam with a laterally arched core as bio-inspired by the woodpecker is numerically investigated. The principal components of the beam comprise a dual-core system sandwiched by the top and bottom laminated CFRP skins. Different materials, including hot melt adhesive, high-density polyethylene (HDPE), acrylonitrile butadiene styrene (ABS), epoxy resin (EPON862), aluminum (Al6061), and mild carbon steel (AISI1018), are considered for the side-arched core layer of the beam for impact efficiency assessment. The aluminum honeycomb takes the role of the second core. Contact force, stress, damage formation, and impact energy for beams equipped with different materials are examined. A diversity in performance superiority is noticed in each of these indicators for different core materials. Therefore, for overall performance appraisal, the impact resistance efficiency index, which covers several chief impact performance parameters, of each sandwich beam is computed and compared. The impact resistance efficiency index of the structure equipped with the AISI1018 core is found to be the highest, about 3-10 times greater than other specimens, thus demonstrating its efficacy as the optimal material for the bio-inspired dual-core sandwich beam system.

• Asian-Australasian Journal of Animal Sciences
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• v.23 no.6
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• pp.825-832
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• 2010

The United Nations Convention on Biological Diversity defines biotechnology as "Any technological application that uses biological systems, dead organisms, or derivatives thereof, to make or modify products or processes for specific use" Biotechnology has made tremendous contributions to improve production efficiency of agriculture during the last century. This article reviews successful examples of application of bio-fermentation in improving swine nutrition efficiency mainly based on the authors'z own research experience. Production of feed grade supplemental amino acids by bio-fermentation allowed nutritionists to formulate accurate feed for optimal lean growth and reduced nitrogen excretion. Recent issues with high feed grain prices caused potential feed quality problems. Bio-fermentation allowed nutritionists to use exogenous supplemental enzymes such as phytase and NSPases in swine diets, thereby improving nutrient utilization and reducing nutrient excretion to the environment. Yeast metabolites are also produced by bio-fermentation and have been repeatedly shown to improve milk production of sows during early lactation even though actual mechanisms are still to be investigated. Bio-fermentation technology also allowed nutritionists to prepare vegetable protein sources with large protein molecules and anti-nutritional factors suitable for feeding newly weaned piglets, as selected microorganisms significantly reduce specific anti-nutritional factors and size of peptides. Preparations of vegetable protein sources suitable for newly weaned pigs will greatly contribute to swine nutrition by providing efficient alternatives to the use of animal protein sources that are often expensive and somewhat against societal preference. Considering the few examples listed above, biotechnology has closely influenced improvement of production efficiency in the swine industry. As we have limited resources to produce meat to satisfy ever-increasing global demands, extensive adaptation of biotechnology to enhance production efficiency should be continued. However, at the same time, wise and careful application of bio-technology should be considered to ensure production of safe food and to meet the expectations of our society.

• Journal of Ginseng Research
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• v.40 no.1
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• pp.28-37
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• 2016

Background: Panax ginseng cannot be cultivated on the same land consecutively for an extended period, and the underlying mechanism regarding microorganisms is still being explored. Methods: Polymerase chain reaction and denaturing gradient gel electrophoresis (PCR-DGGE) and BIO-LOG methods were used to evaluate the microbial genetic and functional diversity associated with the P. ginseng rhizosphere soil in various cultivation ages and modes. Results: The analysis of microbial diversity using PCR-DGGE showed that microbial communities were significantly variable in composition, of which six bacterial phyla and seven fungal classes were detected in P. ginseng soil. Among them, Proteobacteria and Hypocreales dominated. Fusarium oxysporum, a soilborne pathogen, was found in all P. ginseng soil samples except R0. The results from functional diversity suggested that the microbial metabolic diversity of fallow soil abandoned in 2003was the maximum and transplanted soil was higher than direct-seeding soil and the forest soil uncultivated P. ginseng, whereas the increase in cultivation ages in the same mode led to decreases in microbial diversity in P. ginseng soil. Carbohydrates, amino acids, and polymers were the main carbon sources utilized. Furthermore, the microbial diversity index and multivariate comparisons indicated that the augmentation of P. ginseng cultivation ages resulted in decreased bacterial diversity and increased fungal diversity, whereas microbial diversity was improved strikingly in transplanted soil and fallow soil abandoned for at least one decade. Conclusion: The key factors for discontinuous P. ginseng cultivation were the lack of balance in rhizosphere microbial communities and the outbreak of soilborne diseases caused by the accumulation of its root exudates.

• Korean Journal of Organic Agriculture
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• v.18 no.3
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• pp.291-313
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• 2010

The objective of this paper is to apply choice experiment methods to estimate non-market value of organic farming and its policy implication. A preliminary survey shows that the attributes of organic farming are reduce environmental pollution, bio-diversity improvements, cultural diversity improvements and maintain local community, reduce green-house gas emissions, energy saving, landscape improvements and tax for organic farming improvement policy. Questionnaire was eight different choice sets presented to each respondent. Implicit values of the attributive levels of organic farming have been calculated into tax money costs per house. This paper compared the six feasible scenarios in terms of willingness to pay per year. This study is expected to contribute to government's organic farming policies and quantitative information related to practice of organic farming.

• Journal of the Korea Furniture Society
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• v.19 no.4
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• pp.300-306
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• 2008

Nepal is rich country in terms of its vast array of biological diversity. The relationship between local communities and the biological diversity in Nepal is a very entangle one, whereby two-thirds of our population are heavily dependent upon the biodiversity for their survival. The destruction of biodiversity signifies the destruction of people's livelihoods and survival. Biodiversity and genetic resources conservation has been a most significant part of the Nepalese society due to its socio-economic and cultural importance and provides the human race trees for timber, fuel, food, industrial raw materials, pharmaceuticals, beverages and environmental stabilization. Threats to biodiversity at global level is of greater concern, specially, human activities are the greatest factor currently affecting biodiversity, through the use of natural resources by industry, agriculture, hunting, and energy generation.

• Journal of Microbiology and Biotechnology
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• v.27 no.5
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• pp.916-924
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• 2017

Eighty-five Enterococcus faecalis isolates collected from animals (40 isolates), meju (a Korean fermented soybean product; 27 isolates), humans (10 isolates), and various environmental samples (8 isolates) were subjected to multilocus sequence typing (MLST) to identify genetic differences between samples of different origins. MLST analysis resulted in 44 sequence types (STs), and the eBURST algorithm clustered the STs into 21 clonal complexes (CCs) and 17 singletons. The predominant STs, ST695 (21.1%, 18/85) and ST694 (9.4%, 8/85), were singletons, and only contained isolates originating from meju. None of the STs in the current study belonged to CC2 or CC9, which comprise clinical isolates with high levels of antibiotic resistance. The E. faecalis isolates showed the highest rates of resistance to tetracycline (32.9%), followed by erythromycin (9.4%) and vancomycin (2.4%). All isolates from meju were sensitive to these three antibiotics. Hence, MLST uncovered genetic diversity within E. faecalis, and clustering of the STs using eBURST revealed a correlation between the genotypes and origins of the isolates.