• Korean Journal of Food Science and Technology
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• v.25 no.2
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• pp.142-147
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• 1993

For the purpose of fixing solar energy and utilizing water wastes from food industries for SCP(single cell protein), 170 strains of photosynthetic bacteria were isolated from 56 samples. Among 170 strains, B-Ps-106 strain was selected as the most suitable strain and identified as a variant or a relation of Rhodopseudomonas sphaeroides and its growth was better under anaerobic light condition than aerobic condition. The optimum conditions of the cell growth of B-Ps-106 were investigated on soybean-curd whey media. The optimum pH for cell growth was $8.5{\sim}9.0$. The optimum temperature was $30^{\circ}C$ and the optimum light density was above $0.72\;cal/cm^2/min$. The most favorable concentration of $K_2HPO_4\;and\;(NH_4)_2SO_4$ was both 0.9 g/l when added to soybean-curd whey media.

• The Journal of Advanced Prosthodontics
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• v.4 no.2
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• pp.84-88
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• 2012

PURPOSE. To evaluate the efficacy of sodium hypochlorite (1 : 10) and iodophor disinfectants on alginate impressions along with their effect on the survived bacterium count on the gypsum cast. MATERIALS AND METHODS. Four alginate impression on each dentate patients were made, of which Group I were not washed or disinfected, Group II impressions were merely washed with water, Group III were disinfected by spraying with sodium hypochlorite (1 : 10), Group IV were disinfected with iodophor (1 : 213). Gypsum cast (type III) were made from all the impression. Impressions and gypsum cast were swabbed in mid palatal region for bacterial culture. Bacterial colony counting done after 3 days of incubation at $37^{\circ}C$ in blood agar media. The data obtained was analyzed by one way ANOVA test at a significant difference level of 0.05. RESULTS. Group I and Group II showed significantly more bacteria compared to Group III and Group IV. Bacterial colonies on the alginate impression and gypsum cast in group disinfected with Sodium hypochlorite (1 : 10) were 0.18, 0.82 respectively compared to group treated with iodophor (1 : 213). There was an increase in bacterial count on dental cast compared to source alginate impressions. CONCLUSION. Sodium hypochlorite (1 : 10) was found to be better disinfectant for alginate impression. There was an indication of increase in number of bacteria from alginate impression to making of dental cast. Additional gypsum cast disinfectant procedures need to be encouraged to completely eliminate cross infection to dental laboratory.

• The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
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• v.8 no.2
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• pp.210-224
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• 2003

Sulfate reduction is a microbiological process which occurs ubiquitously in anaerobic marine environment. Sulfate reducing bacteria play a significant role in anaerobic decomposition of organic matter and regeneration of inorganic nutrients which supports the primary production in the water column (i.e., benthic-pelagic coupling) and, in special case, could be responsible for the harmful algal bloom in the coastal marine environment. Summary of the sulfate reduction rates reported in various marine sedimentary environments revealed that supply of organic substrates and presence of various electron acceptors (i.e., $O_2$, NO$_{3}$$^{[-10]}$ , Fe(III) and Mn(IV), etc.) for other aerobic and anaerobic respiration directly affect the sulfate reduction rate and relative significance of sulfate reduction in organic matter mineralization. Significance of temperature, macrophytes and bioturbation is discussed as factors controlling supply of organic substrates and distribution of electron acceptors. Finally, we suggest studies on the anaerobic microbiological processes associated with biogeochemical element cycles in the coastal environments of Korea where massive operation of organic enriched fish cage farm, frequent occurrence of toxic algal bloom and hypoxia and conservation of tidal flat are of major environmental issues.

• Korean Journal of Soil Science and Fertilizer
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• v.17 no.1
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• pp.67-76
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• 1984

This experiment was conducted to find out the changes in microflora of submerged soil uncultivated rice plant by application of CNP herbicide (2, 4, 6 - Trichlorophenyl-4-Nitrophenyl ether) under conditions applied with compost, rice straw, glucose or without organic material. The soil, sandy loam textured was incubated in green house for 66 days. Sampling and analysis of microorganisms were carried out during submergence periods. The results were summarilized as follows. 1. Number of aerobic total bacteria was increased by application of CNP herbicide during submerbed 50 days, afterthen, could not seen the difference. The application of rice straw increased number of aerobic bacteria regardless of CNP herbicide application or not, but glucose tended to decrease. 2. Number of Fungi was constantly maintained at $8-20{\times}10^3$ levels during period of submergence regardless of application of CNP herbicide and organic materials or not. 3. The CNP herbicide application tended to decrease the number of actinomycetes, particularly, in the treatments without organic substances and rice straw were remarkably decreased. 4. Anaerobic-and gram-negative bacteria populations were not showed any difference by application of herbicide and organic materials. 5. The ratios of aerobic bacteria to fungi and aerobic bacteria to actinomycetes appeared high values by application of herbicide and of organic substances. 6. At 66 days after submergence, the ratio of chromogenic actinomycetes to the total number of actinomycetes was lowered in application of herbicide. On the other hand, the percentage of both pretense-positive and cellulase-positive actinomycetes to the total isolates were higher in the treatment with herbicide than An without herbicide, particularly. The ratios of pretense-positive actinomycetes were high in the rice straw application regardless of herbicide application or not, but cellulase-positive actinomycetes was not remarkably difference.

• Journal of Species Research
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• v.10 no.3
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• pp.227-236
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• 2021

To obtain unrecorded freshwater bacterial species in Korea, water and sediment samples were collected from streams, lakes, and wetland of the Han River watershed in 2020. Approximately 800 bacterial strains were isolated on R2A agar after aerobic or anaerobic incubation, and identified using 16S rRNA gene sequences. A total of 28 strains, with ≥98.7% 16S rRNA gene sequence similarity with validly published bacterial species but not reported in Korea, were determined to be unrecorded bacterial species in Korea. The unrecorded bacterial strains were phylogenetically diverse and belonged to four phyla, eight classes, 13 orders, 19 families, and 25 genera. The unreported species were assigned to Acetobacter, Alsobacter, Mesorhizobium, Prosthecomicrobium, and Microvirga of the class Alphaproteobacteria; Vogesella, Formosimonas, Aquincola, Massilia, Acidovorax, and Brachymonas of the class Betaproteobacteria; Pseudoxanthomonas, Thermomonas, Lysobacter, Enterobacter, Kosakonia, and Acinetobacter of the class Gammaproteobacteria; Sulfuricurvum of the class Epsilonproteobacteria; Mycolicibacterium, Agromyces, Phycicoccus, and Microbacterium of the class Actinobacteria; Paenibacillus of the class Bacilli; Clostridium of the class Clostridia; and Flavobacterium of the class Flavobacteriia. The details of the unreported species, including Gram reaction, colony and cell morphology, biochemical characteristics, and phylogenetic position are also provided in the description of the strains.

• Applied Biological Chemistry
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• v.49 no.2
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• pp.108-113
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• 2006

This study was conducted to analyze the acidity and turbidity changes of immersion solutions as well as changes in aerobic bacteria, E. coli, anaerobic bacteria, yeast and mold counts of mulberry leaf soybean curds during storages at $4^{\circ}C$ and $25^{\circ}C$ in different immersion solutions such as distilled water, grapefruit seed extract (300 ppm) and alkaline ionic water. The acidities of immersion solutions of distilled water, grapefruit seed extract and alkaline ionic water after 18 days of storage at $4^{\circ}C$ were 0.021, 0.008 and 0.002%, respectively. After 5 days of storage at $25^{\circ}C$ were 0.042, 0.029 and 0.009%, respectively. The turbidities of the above mentioned immersion solutions were 0.50, 0.29 and 0.21 after 18 days of storage at $4^{\circ}C$ and 0.38, 0.34 and 0.27, respectively, after 5 days of storage at $25^{\circ}C$. The acidity and turbidity changes of immersion solutions were sensitive to storage temperatures. The aerobic bacteria count of mulberry leaf soybean curds after 18 days of storage at $4^{\circ}C$ was still below $10^7\;CFU/g$, the beginning point of soybean curd putrefaction; in contrast, this value was reached within one day in distilled water at $25^{\circ}C$ and between 2 and 3 days in alkaline ionic water. Grapefruit seed extract and alkaline ionic water had a better preservative effect at $4^{\circ}C$ than at $25^{\circ}C$ storage temperature.

• Korean Journal of Microbiology
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• v.20 no.2
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• pp.53-66
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• 1982

1. When Chong Ju and Chung Ju soils possessing different physicochemical properties were treated with 500 ppm of TOK and incubated in flooded anaerobic condition for 2, 4, and 6 months, respectively, they produced 4-Chloro-4'-amino diphenyl ether, 2,4-Dichloro-4'-amino diphenyl ether(amin-TOK), N-[4'-(4-Chlorophenoxy)] phenyl acetamide, and N-[4'-(4-Chlorophenoxy)] phenyl formamide as the metabolities. This result indicates that TOK undergose the reduction of its $NO_2\;to\;NH_2$ group, dechlorination, acetylation, and formylation under this condition. The cleavage of ether linkage does not occur. In addition, TOK degrades more readily in Chung Ju soil which is characterized by pH 6.43 and higher contents of $Ca^{++}$ and C.E.C. than in Chong Ju soil which is lower in pH, $Ca^{++}$, and C.E.C. 2. In the aerobic incubation of TOK of 25ppm in Chung Ju soil suspension for 21 days, the ratio of the resulting metabolites, TOK : amino-TOK : 4-Chloro-4'-amino diphenyl ether was 100 : 130 : 76. Meanwhile, in the 42 day incubation, the ratio was 100 : 19 : 5, which indicates that TOK in aerobic condition dose not necessrily degrade as a function of the incubation period. 3. The citrate buffer extract of Chung Ju soil has the capability of degrading TOK, which was verified to be due to the action of the microorganisms involved. 4. Twelye strains of soil bacteria were isolated from the TOK-treated soils. In the incubation of TOK in pure cultures of the respective isolates, the strain T-1-1 isolated from Chong Ju soil had almost no degradability whereas the strain T-2-3 was the most potent. The degradation of TOK by the isolates constituted mostly the reduction of the nitro group to amino group. 5. In a test for the degradability of TOK by some selected microorganisms, Pseudomonas species were more potent than fungi. Yet, Isolate B which had been isolated from Chung Ju soil suspension was the most potent.

• Journal of Microbiology and Biotechnology
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• v.26 no.3
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• pp.441-451
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• 2016

Squalene is a linear triterpene formed via the MVA or MEP biosynthetic pathway and is widely distributed in bacteria, fungi, algae, plants, and animals. Metabolically, squalene is used not only as a precursor in the synthesis of complex secondary metabolites such as sterols, hormones, and vitamins, but also as a carbon source in aerobic and anaerobic fermentation in microorganisms. Owing to the increasing roles of squalene as an antioxidant, anticancer, and anti-inflammatory agent, the demand for this chemical is highly urgent. As a result, with the exception of traditional methods of the isolation of squalene from animals (shark liver oil) and plants, biotechnological methods using microorganisms as producers have afforded increased yield and productivity, but a reduction in progress. In this paper, we first review the biosynthetic routes of squalene and its typical derivatives, particularly the squalene synthase route. Second, typical biotechnological methods for the enhanced production of squalene using microbial cell factories are summarized and classified. Finally, the outline and discussion of the novel trend in the production of squalene with several updated events to 2015 are presented.

• Food Science of Animal Resources
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• v.39 no.6
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• pp.863-876
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• 2019

The thermal-death times of Listeria monocytogenes were determined in inoculated restructured goat steak at 60℃, 65℃, and 70℃ of sous-vide temperatures. D-values of L. monocytogenes in inoculated restructured goat steak ranged from 7.27 min at 60℃ to 0.46 min at 70℃. Times need to yield at least a 6 log reduction of L. monocytogenes at their temperatures for this product were 47, 12, and 3 min, respectively. After sous-vide, all microbial counts in non-inoculated samples were not detectable, except the aerobic and anaerobic mesophilie and lactic acid bacteria counts were lower than 2 Log CFU/g. For sous-vided and grilled sous-vided samples, sous-vide loss and surface shrinkage were the lowest in samples sous-vided at 60℃ for 47 min (p<0.05). These samples demonstrated the lowest CIE L^*, shear force, hardness, gumminess and chewiness and the highest CIE a^* and hue angle (p<0.05). Therefore, sous-vide at 60℃ for 47 min provided convenient ready-to-cook restructured goat steak for microbiology safety and optimization of physicochemical quality.

• Archives of Reconstructive Microsurgery
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• v.12 no.1
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• pp.13-18
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• 2003

Fournier's gangrene is a synergistic necrotizing fasciitis of the perineal, perirectal and urogenital area and can be fatal unless treated in early stage. Perianal and urogenital infections are common causes of the disease but it can occur after artificial procedure on perineal area using by surgical instruments. It is mixed aerobic and anaerobic infection and E. coli is the most common causative bacteria. Untill now many investigators have focused on early diagnosis, preserving hemodynamic stability, broad-spectrum systemic antibiotics and treatment of underlying disease in management of Fournier's gangrene. The authors have experienced five patients of chronic liver disease whose necrotizing perineal infections developed spontaneously and treated them aggressively as described above and reconstructed perineal soft tissue defects using by various surgical methods, then we got good results both functionary and cosmetically. From now on, we would better reconstruct soft tissue defect of perineum with skin graft or pedicled flap in early stage when treat Fournier's gangrene, thereafter we can get an ultimate increase in patient's life quality.