• Journal of Microbiology and Biotechnology
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• v.27 no.2
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• pp.226-233
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• 2017

Jeung-pyun, a fermented rice cake, is prepared by fermenting rice sourdough using makgeolli, a traditional Korean rice wine, in the presence of yeast and lactic acid bacteria (LAB). The goal of this study was to conduct biochemical and microbial analyses of five different rice sourdoughs, each fermented with a different commercial makgeolli, using culture-dependent and culture-independent approaches. All sourdough samples fermented with different makgeolli for 6.5 h showed different profiles in pH, total titratable acidity, organic acid concentration, and microbial growth. LAB belonging to different genera were identified based on colony morphology on modified MRS and sourdough bacteria agar medium. PCR-denaturing gradient gel electrophoresis analyses of the five sourdoughs showed different bands corresponding to LAB and yeast. 16S/26S rRNA gene sequence analyses of the samples confirmed that the predominant LAB in the five fermented rice doughs was Lactobacillus plantarum, Lb. pentosus, and Lb. brevis. Various other Lactobacillus spp. and Saccharomyces cerevisiae were common in all five fermented samples. This study provides comprehensive and comparative information on the microflora involved in fermentation of rice sourdough and signifies the need to develop effective starters to enrich the quality of jeung-pyun.

• Korean Journal of Environmental Agriculture
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• v.33 no.1
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• pp.52-56
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• 2014

BACKGROUND: It is known that impacts of climate change on damage occurrence by insect pests and diseases are increasing. The negative effects of climate change on production will threaten our food security. It is needed that on the basis of analysis of the impacts, proper strategies in response to climate change are developed. METHODS AND RESULTS: The objective of this paper is to estimate impacts of climate change on rice damage occurrence by insect pests and diseases, using the panal model which analyzes both cross-section data and time series data. The result of an analysis on impacts of climate change on rice damage occurrence by pest insect and disease showed that the damage occurrence by Rice leaf roller and Rice water weevil increased if temperature increased, and damage occurrence by Stripe, Sheath blight, and Leaf Blast increased if precipitation(or amount of sunshine) increased(or decreased). CONCLUSION: Adaptation strategies, supplying weather forecasting information by region, developing systematical strategies for prevention of damage occurrence by pest insect and disease, analyzing the factors of damage occurrence by unexpected pest insect and disease, enforcing international cooperation for prevention of damage occurrence are needed to minimize the impacts of damage occurrence on rice production.

• Journal of Korea Technical Association of The Pulp and Paper Industry
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• v.41 no.3
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• pp.22-28
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• 2009

The rice hull could be the one of the most abundant agricultural waste in Korea. Since the efficient utilization of agricultural waste or byproducts of food industry would be critical for the sustainable growth, this study conducted the investigation of the chemical composition and the morphological properties of rice hull and rice hull fiber. It was found that there was big difference between the outer surface and the inner surface in the chemical composition and the morphological properties. Expecially, the outer surface showed the rugged patterns in which most of silica of rice hull existed. Little or no silica was found in the inner surface and rice hull fiber. The average fiber length of rice hull fiber was 0.45mm which was shorter than that of hardwood fiber. Rice hull fiber showed a round long shape which is typical shape of non-wood fibers

• Journal of Korean Society of Rural Planning
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• v.20 no.4
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• pp.35-43
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• 2014

The purpose of this study is to analyze emergy flows of rice for evaluating the value of rice production and sustainability. Emergy analysis evaluates the sustainability of systems or processes considering all the inputs to make a product or a sevice. In this study, we analyzed the emergy flows and indices of rice productionand compared the regional emergy values using statisticcal analysis: input materials, hours per unit area(10a), and production costs. As the results, we found that the rates of external investment (EIR= 18.87) and environmental loading (ELR=21.7) are significantly high during the rice cultivation. However, emergy yield ratio(EYR) shows that rice is a valuable resource because EYR is 5.12 and environmental Sustainability IndexSI value is as low as 0.24 and it shows rice has low sustainability. This study also shows that Chungcheongnam-do has the highest SI value for rice production due to low environmental loading and abundant natural energy during rice cultivation. These results of rice emergy flows and sustainability assessments could provide a way of sustainable rice cultivation with decrease of environmental loading from fertilizer.

• Journal of Practical Agriculture & Fisheries Research
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• v.4 no.1
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• pp.39-44
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• 2002

This paper was studied on a strategy in rice production under New round system of WTO(World Trade Organization) in Korea. Under enactment of New round system in WTO rice will be opened at the world market and thus rice growers will compete with this marketing system. In this regard, rice industry in Korea would be "a theory of rice triangle" such as high quality, low cost, and environmental friendly system. High quality rice would be obtained through a cultivar, cultivation technology, and quality control(QC) to compete against oversea's dealer. Lower cost in rice production should be concentrated into rapid decrease in rural population and into introducing for young generation. Rice cultivation has been played major role in this peninsula in terms of a preservation of water resource, fresh air and prevention of soil erosion.

• Korean Journal of Plant Resources
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• v.19 no.6
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• pp.692-696
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• 2006

This study was conducted to evaluate the effect of seed disinfectant, in control of brown leaf blight, growth characteristics, and dry root yield in the cultivation of Alisma plantago after early maturing rice cropping. Experimental plot was laid out in split plots design with three replications. The major seed disinfectants were benomyl Wp, 20%, Captan Wp, 50%, Triferine Ec, 17%, Etridia zole Ec, 25%, and Thioplant-mythyl Wp, 50%. Even though seed disinfectant treated had no effect on the growth and flowering date of Alisma plantago, dry root yield was increased largely with benomyl Wp, 20%, in seed disinfectant than in the other seed disinfectants and contorl. All seed disinfectants had no injury with standard dosage. But all seed disinfectants had slight injury in the double dosage level for the Alisma plantago. On the basis of yield, vegetative and disease paramerer, benomyl Wp (20%) ($100g/20{\ell}$) had shown superior performance, however, all the seed disinfectants are effective as compare to without treatment.

• Journal of The Korean Society of Agricultural Engineers
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• v.60 no.4
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• pp.93-103
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• 2018

The aim of this study is to apply the Water-Energy-Food-Land Nexus approach which can analyze the trade-offs among resources, and assess the holistic impacts of food security. First, we applied rice as a study crop and analyzed the trend of consumption of rice and the area of paddy fields. Second, the portfolios of water, energy, and land for rice production were constructed using data of footprints and productivity. Finally, the self-sufficiency ratio (SSR) of rice in target year was set as food security scenario and assessed the impacts of food security on water, energy, and land availability. In 2030, the SSR of rice decreased to 87 %, and water use for producing rice decreased from 4,728 to $3,350million\;m^3$, and the water availability index increased from 0.33 to 0.53. However, food security is essential issue and we set the 50 % and 100 % SSR of rice as high and low food security scenarios. For 100% SSR in 2030, about $3,508million\;m^3$ water was required and water availability index reached to 0.5. In other words, there is the trade-off between food security and water-energy-lands availability. Therefore, it is difficult to make a decision whether a high level of SSR is better or worse. However, this study showed the both positive and negative impacts by change of food security and it can be useful for setting the policy decision considering both food security and sustainable resource management at the same time.

• Journal of Climate Change Research
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• v.4 no.4
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• pp.317-330
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• 2013

The yield of rice production is affected severely by abnormal weather events, such as flood, drought, high temperature etc. The objective of this paper is to assess impacts of abnormal weather events on rice production, using a panel model which analyzes both cross-section data and ti- me series data. Abnormal weather is defined as the weather event which goes beyond the range of ${\pm}2{\sigma}$ from the average of a weather factor. The result of an analysis on impacts of high temperature on rice production showed that the yield of rice was decreased 5.8% to 16.3% under the conditions of extremely high temperature, and it was decreased 8.8 to 20.8% under the conditions of both extremely high and heavy rain. Adaptation strategies, development of new varieties enduring high temperature and heavy rain, adaptation of crop insurance, modernization of irrigation facilities are needed to minimize the impacts of abnormal weather on rice production, and to stabilize farmers' income.

• Journal of Microbiology and Biotechnology
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• v.27 no.10
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• pp.1736-1743
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• 2017

Sourdough is made by fermentation of dough by lactic acid bacteria (LAB) and yeast to improve bread properties like volume, flavor, and texture. A Korean traditional sourdough was made by fermenting rice flour with rice wine (makgeolli) and used to make sponge-like bread (jeung-pyun). The aim of this study was to investigate the microbial diversity of makgeolli products and their influence on the organoleptic quality of jeung-pyun. Three commercial makgeolli were tested for jeung-pyun production, with each product exhibiting varied dough swelling rates and organoleptic qualities, and among them, J-product was ranked highest in texture and taste. Microbial analysis of the three makgeolli also showed a big difference in their population and diversity. J-product had the highest LAB and yeast counts, and the predominant species were Lactobacillus casei, Lactobacillus brevis, Leuconostoc pseudomenteroides, and Saccharomyces cerevisiae. Using J-product, sourdough was fermented at $25^{\circ}C$, $30^{\circ}C$, and $35^{\circ}C$, and the microbial growth in and textural properties of jeung-pyun were examined by instrumental and sensory tests. At high temperature ($35^{\circ}C$), the rates of dough swelling and acidification were fast due to rapid microbial growth mainly caused by LAB, resulting in a short leavening time and soft and sour jeung-pyun. Sensory tests showed consumer preference for the soft and mild-sour jeung-pyun. This study shows that LAB in makgeolli play key roles in production of jeung-pyun, influencing the textural and sensory properties. For the production of high-quality jeung-pyun, development of LAB starters with high gas productivity and low acidity and establishment of an optimal fermentation procedure for rice dough are necessary.

• Asian-Australasian Journal of Animal Sciences
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• v.24 no.11
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• pp.1560-1568
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• 2011

This study was conducted to evaluate the yield, nutrient characteristics, ruminal solubility, degradability and disappearance of spent mushroom (Agaricus bisporus) substrates for ruminants. The annual yield of spent Agaricus bisporus substrates was measured to be about 210,000 tons (M/T) in South Korea. The surface soil-removed spent substrates had nutritional characteristics of high crude ash (375 g/kg) and Ca (32 g/kg), medium protein (134 g/kg CP), and high fiber (384 g/kg NDF on a DM basis). Compared with initial mushroom substrates, spent mushroom substrates had twice higher (p<0.0001) CP content and 22.0% lower (p<0.0001) NDF content on an organic matter basis. Compared with raw rice straw, spent rice straw had much higher (p<0.05) predicted ruminal degradabilities and disappearances of DM and CP and a little lower (p<0.05) predicted degradability and disappearance of NDF. In conclusion, the general feed-nutritional value of spent mushroom (Agaricus bisporus) substrates appeared to improve after cultivation of mushrooms.