• KSBB Journal
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• v.26 no.5
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• pp.365-373
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• 2011

Effective Microorganisms (EM), a fermented medium developed by Professor Higa at the University of the Ryukyus, is a mixed culture containing dozens of microorganisms which are beneficial to nature including people, animals, plants and many microbial species in environment. EM is known to contain more than 80 kinds of anaerobic or aerobic microbes including photosynthetic bacteria, lactic acid bacteria, yeast, actinomycetes, fungi and so on, with yeast, lactic acid bacteria and photosynthetic bacteria as the main species of EM. Antioxidant effect generated by the concert of complex coexistence and coprosperity among these microbes is considered to be the main source of EM benefits. Currently, EM is earning an increasing attention with applications in agriculture, forestry, animal husbandry, fisheries, environment and medicine among others. At the same time, however, a quantitative interpretation of EM system based on a mixed culture model needs efforts from biochemical engineers for efficient production and further promotion of EM. In this paper, we describe the functions of major microbes in EM and current researches and applications of EM in agriculture, forestry, animal husbandry, fisheries, environment and medicine.

• 한국신재생에너지학회:학술대회논문집
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• 2006.06a
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• pp.478-481
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• 2006

Energy is vital to global prosperity, yet dependence on fossil fuels as our primary energy source contributes to global climate change environmental degradation, and health problems. Hydrogen $(H_2)$ offers tremendous potential as a clean renewable energy currency. Hydrogen has the highest gravimetric energy density of any known fuel and is compatible with electrochemical and combustion processes for energy conversion without producing carbon-based emission that contribute to environmental pollution and climate change. Numerous methodologies have been developed for effective hydrogen production. Among them, the biological hydrogen production has gained attention, because hydrogen can be produced by cellular metabolismunder the presence of water and sunlight. The green alga Chlamydomonas reinhardtii is capable of sustained $H_2$ photoproduction when grown under sulfur deprived condition. Under sulfur deprived conditions, PSII and photosynthetic $O_2$ evolution are inactivated, resulting in shift from aerobic to anaerobic condition in the culture. After anaerobiosis, sulfur deprived algal cells induce a reversible hydrogenase and start to evolve $H_2$ gas in the light. According to above principle, we investigated the effect of induction parameters such as cell age, cell density. light intensity, and sulfate concentration under sulfur deprived condition We also developed continuous hydrogen production system by sulfate re-addition under sulfur deprived condition.

• Journal of Microbiology and Biotechnology
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• v.16 no.10
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• pp.1518-1522
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• 2006

In the present study, it was observed how the phage-host system that is naturally reproduced in activated sludge is affected by the host inoculation. The system of Microlunatus phosphovorus and its phages was selected as the phage-host system native to an activated sludge system operated for 19 days under sequencing anaerobic-aerobic conditions with glutamate as the main carbon source. The phage-host system related to M. phosphovorus was monitored by plaque assay for the phages and by fluorescent in situ hybridization (FISH) for the bacterial host. In addition, the whole phage structure was also monitored by pulsed-field gel electrophoresis (PFGE). During the first 9 days, the phage-host system was more or less steady at approx. 9% (FISH/ DAPI) for M. phosphovorus and approx. 10,000 PFU/ml for its lytic phages. Microlunatus phosphovorus JCM9379 was inoculated into the activated sludge on day 10. Right after the inoculation, M. phosphovorus was approx. 24% (FISH/DAPI) whereas its lytic phages dropped down to approx. 500 PFU/ ml. After the host inoculation (within 9 days), however, the phage-host system eventually reverted to its original level in each population. On the other hand, the whole phage structure was not significantly changed by M. phosphovorus inoculation but stable throughout the process operation. Only the minor change that four phage groups gradually became abundant after the host inoculation was observed.

• Journal of the Korean Society of Food Science and Nutrition
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• v.24 no.5
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• pp.803-810
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• 1995

Co-immobilized mixed culture system(A-Z system) composed of two different oxygen-demanding strains, aerobic(Aspergillus awamori) and anaerobic(Zymomonas mobilis) strains, in a Ca-alginate gel beads was developed to increase ethanol production from raw starch as a carbon source. Optimal mixture ratio of A. awamori and Z. mobilis was $1.25{\times}10^{9}\;spores/L-gel$ and 0.5g cells/L-gel, respectively. After 120 hours of cultivation, gel beads distinguished oxygen-rich surface for A. awamori from oxygen-deficient central part for Z. mobilis. At A-Z culture system, yield of ethanol on glucose, $Y_{p/s}=0.18$, was very low and there was high leakage of cells from surface of gel beads. At A-Z 36 cultrue system with changing silicon check valve for cotton plug at 36 hours in A-Z culture system, there was no cell leakage from gel beads, pH was maintained at around 4.3 during cultivation, and yield of ethanol on glucose, $Y_{p/s}=0.36$, showed 2 times higher than that of control culture system(cotton plug culture).

• Journal of Environmental Health Sciences
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• v.37 no.2
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• pp.124-132
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• 2011

Biofilm and aeration tank of pilot and full RABC (rotating activated Bacillus contactor) plant were analyzed to characterize and determine bacterial community structure in food wastewater treatment system at winter. Concentration of heterotrophic bacteria and Bacillus group was $10^7$ and $10^5$ CFU/ml, respectively, at biofilm of pilot-plant while others represented $10^6$ and $10^4$ CFU/ml, respectively. Five and eight phyla were detected at biofilm of pilot- and full-plant, respectively, by 16S rDNA sequencing. Biofilm of pilot-plant was dominated by ${\beta}$-Proteobacteria (38.8%), ${\gamma}$-Proteobacteria (22.4%), and Bacteroidetes (12.2%), and the most dominant genus was Zoogloeae genus (22.4%). Candidate division TM7 (12.5%) was only detected at biofilm of full-plant and it was dominated by Bacteroidetes (33.3%), ${\gamma}$-Proteobacteria (29.2%), and ${\beta}$-Proteobacteria (20.8%). Clostridium genus specific primer set enabled to detect the sequences of Clostridium genus. These suggested that anaerobic and aerobic bacteria were coexisted even from the initial period of biofilm formation and ${\beta}$-Proteobacteria, ${\gamma}$-Proteobacteria and Bacteroidetes were major phyla in biofilm of food wastewater treatment system at winter.

• Journal of Korean Society on Water Environment
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• v.21 no.6
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• pp.624-629
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• 2005

The purpose of this study is to investigate the performance of nitrogen removal using autotrophic microorganism in the Membrane-Attached Biofilm Reactor (MABR). The treatment system consists of an aerobic MABR (R1) for nitrification and an anaerobic MABR (R2) for hydrogenotrophic denitrification. Oxygen and hydrogen were supplied through the lumen of hollow-fiber membranes as electron acceptor and donor, respectively. In phase Ι, simultaneous organic carbon removal and nitrification were carried out successfully in R1. In phase II, to develop the biofilm on the hollow-fiber membrane surface and to acclimate the microbial community to autotrophic condition, R1 and R2 were operated independently. The MABRs, R1 and R2 were connected in series continuously in phase III and operated at HRT of 8 hr or 4 hr with $NH_4{^+}-N$ concentration of influent, from 150 to 200 mgN/L. The total nitrogen removal efficiency reached the maximum value of 99% at the volumetric nitrogen loading rate of $1.20kgN/m^3{\cdot}d$ in the combined MABR system with R1 and R2. The results in this study demonstrated that the combined MABR system could operate effectively for the removal of nitrogen in wastewater not containing organic materials and can be used stably as a high rate nitrogen removal technology.

• Journal of Environmental Health Sciences
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• v.18 no.2
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• pp.67-74
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• 1992

The lab-scale biological A$_{2}$O system was applied from treating piggery wastewater highly polluted organic material which nitrogen and phosphorous are much contained relatively in conversion with other wastewater. The objective of this study was to investigate the effect of variance parameters on the treatability of this system according to operation conditions. An obtained experimental data were analysed by using principal component analysis (PCA) method. The results are summarized as follows: 1. From Varimax rotated factor loading in raw wastewater, variance of factor 1 was 36.8% and cumulative percentage of variance from factor 1 to factor 4 was 81.5% and of these was related to BOD, TKN and BOD loading. 2. In anaerobic process, variance of factor 1 was 33.5% and cumulative percentage of variance from factor I to factor 4 was 81.8% and of these was related to PO$_{4}$-P, BOD, DO and Temperature. 3. In anoxic process, variance of factor 1 was 30.1% and cumulative percentage of variance from factor i to factor 4 was 84.3% and of these was related to pH, DO, TKN and temperature. 4. In aerobic process, variance of factor 1 was 43.8% and cumulative percentage of variance from factor 1 to factor 4 was 81.5% and of these was highly related to DO, PO$_{4}$-P and BOD. 5. It was better to be operated below 0.30 kg/kg$\cdot$day F/M ratio to keep over 90% of BOD and SS, 80% of TKN, and 60% of PO$_{4}$-P in treatment efficiencies. 6. Treatment efficiencies was over 93% of BOD and SS, 81% of TKN and 60% of PO$_{4}$-P at over 20$^{\circ}$C, respectively.

• Journal of Microbiology
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• v.43 no.3
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• pp.257-259
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• 2005

Although automated continuous-monitoring blood culture systems are both rapid and sensitive, false-positive and false-negative results still occur. The objective of this study, then, was to evaluate negative results occurring with BacT/Alert 3D blood culture systems. A total of 1032 samples were cultured with the BacT/Alert 3D automated blood culture system, using both aerobic (BPA) and anaerobic (BPN) media, and 128 of these samples yielded positive results. A total of 904 negative blood samples were then subcultured in $5\%$ sheep blood agar, eosin methylene blue, chocolate agar, and sabouraud-dextrose agar. Organisms growing on these subcultures were subsequently identified using both Vitek32 (bioMerieux, Durham, NC) and conventional methods. Twenty four $(2.6\%)$ of the 904 subcultures grew on the subculture media. The majority $(83.3\%)$ of these were determined to be gram-positive microorganisms. Fourteen $(58.3\%)$ were coagulase-negative staphylococci, two $(8.3\%)$ were Bacillus spp., one $(4.2\%)$ was Staphylococcus aureus, and one $(4.2\%)$ was identified as Enterococcus faecium. Streptococcus pneumoniae and Neisseria spp. were isolated together in two $(8.3\%)$ vials. Gram-negative microorganisms comprised $12.5\%$ of the subcultures, of which two $(8.3\%)$ were found to be Pseudomonas aeruginosa, and one $(4.2\%)$ was Pseudomonas fluorescens. The other isolate $(4.2\%)$ was identified as Candida albicans. We conclude that the subculture of negative results is valuable in the BacT/Alert 3D system, especially in situations in which only one set of blood cultures is taken.

• Journal of the Korean Society of Urban Environment
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• v.18 no.4
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• pp.401-408
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• 2018

EQPS (Effluent Quality Prediction System, Dynamita, France) was applied to analyze the appropriateness of the design of a bioreactor in A sewage treatment plant. A sewage treatment plant was designed by setting the design concentration of the secondary clarifier effluent to total nitrogen and total phosphorus, 10 mg/L and 1.8 mg/L, respectively, in order to comply with the target water quality at the level of the hydrophilic water. The retention time of the 4-stage BNR reactor was 9.6 hours, which was 0.5 for the pre-anoxic tank, 1.0 for the anaerobic tank, 2.9 for the anoxic tank, and 5.2 hours for the aerobic tank. As a result of the modeling of the winter season, the retention time of the anaerobic tank was increased by 0.2 hours in order to satisfy the target water quality of the hydrophilic water level. The default coefficients of the one step nitrification denitrification model proposed by the software manufacturer were used to exclude distortion of the modeling results. Since the process modeling generally presents optimal conditions, the retention time of the 4-stage BNR should be increased to 9.8 hours considering the bioreactor margin. The accurate use of process modeling in the design stage of the sewage treatment plant is a way to ensure the stability of the treatment performance and efficiency after construction of the sewage treatment plant.

• KSBB Journal
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• v.10 no.5
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• pp.561-567
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• 1995

Using superoxide dismutase (SOD)-deficient mutants of Saccharomyces cerevisiae, the oxygen toxicity induced by paraquat was studied. In aerobic culture condition, yeasts lacking MnSOD (milochondrial SOD) showed more significant growth retardation than CuZnSOD (cytoplasmic SOD)-deficient yeasts. However, not so big differences in growth pattern of those mutants compared with wild type were observed under anaerobic condition. When exposed to paraquat, the growth of yeasts lacking CuZnSOD was severely affected by higher than 0.01mM of paraquat in culture medium. By the analysis of several cellular components ivolved in free radical generating and scavenging system, it was found that, under aerobic condition, the content of lipid peroxides in cell membrane as well as cellular activity of glutathion peroxidase of CuZnSOD-deficient mutants was increased in the presence of paraquat, although significant decrease of catalase activity was observed in those stratns. In MnSOD-deficient yeast, however, increment in cellular activity of glutathion peroxldase and catalase by paraquat was observed without any deterioration of membrane lipid. It implies that the lack of mitochondrial SOD could be compensated by both of glutathion peroxldase and catalase, but that only glutathion peroxidase might act for CuZnSOD in cytoplasm. In contrast, all of SOD-deficient mutants showed a significant decrease in catalase activity, but slight increase in the activities of glutathion peroxidase, when cultivated anaerobically in the medium containing paraquat. Nevertheless, any significant changes of lipid peroxides in cell membranes were not observed during anaerobic cultivation of SOD-deficient mutants. It suggests that a little amount of free radicals generated by paraquat under anaerobic condition could be sufficiently overcome by glutathion peroxidase but not by catalase.