• 한국미생물·생명공학회지
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• 제47권4호
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• pp.621-629
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• 2019

In this study we attempted to screen bacteria and fungi that generate electricity while treating wastewater using optimized double-chamber microbial fuel cell (MFC) system parameters. Optimization was carried out for five best exoelectrogenic isolates (two bacteria and three fungi) at pH values of 6.0, 7.5, 8.5, and 9.5, and temperatures of 30, 35, 40, and 45℃; the generated power densities were measured using a digital multimeter (DT9205A). The isolates were identified using molecular characterization, followed by the phylogenetic analysis of isolates with known exoelectrogenic microorganisms. The bacterium, Proteus species, N6 (KX548358.1) and fungus, Candida parapsilosis, S10 (KX548360) produced the highest power densities of 1.59 and 1.55 W/m² (at a pH of 8.5 and temperatures of 35 and 40℃) within 24 h, respectively. Other fungi-Clavispora lusitaniae, S9 (KX548359.1) at 40℃, Clavispora lusitaniae, S14 (KX548361.1) at 35℃-and bacterium-Providencia species, N4 (KX548357.1) at 40℃-produced power densities of 1.51, 1.46, and 1.44 W/m², respectively within 24 h. The MFCs achieved higher power densities at a pH of 8.5, temperature of 40℃ within 24 h. The bacterial isolates have a close evolutionary relationship with other known exoelectrogenic microorganisms. These findings helped us determine the optimal pH, temperature, evolutionary relationship, and exoelectrogenic fungal species other than bacteria that enhance MFC performance.

• Asian-Australasian Journal of Animal Sciences
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• 제18권8호
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• pp.1098-1104
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• 2005

The trial was carried out on twenty-one Friesian cows at the end of eight months gestation, nine multiparous and twelve primiparous; allocated into three groups (1 control, 2 and 3 experimental). The same diet was administred to all three groups before partum (12.8 kg DM/head/day) and after partum (18.8 kg DM/head/day). The cows in groups 2 and 3 received two different daily quantities of amino-acid chelated chromium (0.6 and 1.2 mg Cr/kg DM) from 4 weeks prior to presumed parturition to 6 weeks after. The milk yield control was carried out at 15, 30, 42 and 60 days. All animals were immunised two weeks prior to the presumed parturition and two weeks after with the following antigens: ovalbumin and brucellergene. Blood samples were collected weekly to monitor humoral and cell-mediated immune responses. When analysing the results of antibody immunity (ovalbumin) in the sixth blood collection both treated groups significantly increased compared to group 1 (0.5230 and 0.4536 vs. 0.1812 OD; p<0.05). The results of the cell-mediated immune response (brucellergene) had significant differences (p<0.10) in correspondence to the third (between group 2 and control) and the fifth (between groups 3 and 2) blood collection. Significant differences in fat corrected milk were observed at 42 days between group 3 and the other two groups (31.01 vs. 26.99 and 28.66 kg/d, p<0.05) and at 60 days between group 3 and control (30.88 vs. 26.69 kg/d, p<0.05). Before partum and at partum a positive immune response was obtained with a lower dose of chromium. After partum a positive immune response, anti-OVA indicator, was obtained with the higher dose of chromium while, $\gamma$-IFN indicator, with the lower dose. A significant increase of the milk yield resulted at both 42 and 60 days with the highest level of chromium.

• Asian-Australasian Journal of Animal Sciences
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• 제18권12호
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• pp.1800-1812
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• 2005

Aquaculture pollution is a major concern among the entrepreneurs, farmers and researchers. Excess discharge of phosphorus and nitrogen into the water bodies is the principal pollutant responsible for this. Plant-based feed ingredients due to its high phytic acid content enhances both nitrogen and phosphorus discharge thereby increasing the pollution level. Dietary phytase treatment is probably the best answer to address this problem. This review explains the nature and properties of phytate, its interactions with other nutrients and the application of phytase in aquafeed to reduce the pollution. This review also covers the different biotechnological aspects for lowering the phytic acid level in the common aquafeed ingredients, as an alternate approach to controlling the pollution level. Some of future research needs have also been highlighted to attract the attention of more researchers to this area.

• Journal of Nutrition and Health
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• 제24권2호
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• pp.77-86
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• 1991

Changes in total lipid content. total cholesterol content and fatty acid composition of human milk were investigated longitudinaly from 2-5 days to 12 weeks postpartum Milk samples were collected from 19 Korean lactating women at 2-5 days and at 1. 2. 4. 6. and 12 weeks postpartum. The obtained results were as follows : On average the daily energy intake protein intake and fat intake of Korean lactating women was 1812 kcal 72.5g and 29.8g respectively. The composition ratio of energy consis-ting of protein fat and carbohydrate was 16:15:69 The total lipid content increased from 1.39g/이 at 2-5 days to 2.86g/dl at 12 weeks ; while the total cholesterol concentration (mg/g) decreased significantly with time following postpartum. The total unsaturated fatty acids content was higher in colostrum than in mature milk. and the total saturated fatty acids were higher in mature milk. The average DHA content was 0.55% and the P/S ratio of human milk lipids was 0.37.

• 한국표면공학회:학술대회논문집
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• 한국표면공학회 1998년도 춘계학술발표회 초록집
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• pp.7-7
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• 1998

1812년 영국의 Humphrey Davy에 의해서 정립되기 시작한 음극방식(Cathodic P Protection)기술은 1900년대 중반이후의 유럽과 미국의 비약적인 발전을 거쳐 이제 세계적으로 철강의 방식법중 빼놓을 수 없는 주요한 기술이 되었다. 1970년대초부터 우리나라에 채용되기 시작한 음극방식기술은 현재 항만, 지중, 열교환기, 화학플랜트 등 다양한 분야에 적용되고 있다. 아직 국내의 아쉬운 점이라면 기술도입 이후 신기술의 개발노력이 거의 이루어 지지 못하고, 해외에서 개발된 새로운 장치나 신기술들을 산발적으로 수입/적용해 왔다는 것이다. 이제 우리나라도 산업의 분야에 따라서는 상당한 방식시설을 보유 하고 있음에도 아직도 국내의 환경에 적합한 음극방식기술의 개발과 심도있는 연구 및 기술축적이 부족한 형편이다. 그 원인으로는 광범위하게 발전해 가는 해외기술 에 대한 정보부족을 먼저 꼽을 수 있으며 국내의 기술 및 연구개발에 투자가 미약 하다는 것이 또하나의 이유라 하겠다. 본 강의는 상기 원인중 음극방식에 대한 해외기술정보를 소개하기 위한 것으로 해외에서 최근에 개발된 음극방식관련 각종 장치를 소개하고 전반적인 산업분야의 음극방식법 응용연구의 방향을 발표하며, 부가하여 읍국방식관련 각종 규정의 소개를 하고자 한다. 제한된 정보로 방식산업에 직접 관계하는 분에게는 부족한 기술 정보가 될지 모르나 전반적인 음극방식기술에 대한 실태를 파악하는데는 조그마한 도움이 될 수 있을 것이다.

• Journal of Microbiology and Biotechnology
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• 제29권8호
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• pp.1266-1272
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• 2019

A bacterial strain, labeled $UR11^T$, was isolated from green alga Ulva pertusa collected from Jeju Island, Korea. $UR11^T$ was identified as a gram-negative, rod-shaped, motile by gliding and aerobic bacterial strain with yellow colonies on R2A plates. The strain $UR11^T$ grew over at a temperature range of $10^{\circ}C$ to $30^{\circ}C$ (optimally at $25^{\circ}C$), a pH range of 6.0-11 (optimally at pH 7.0) and a Nacl range of 0.5-5% Nacl (w/v). Phylogenetic analysis based on 16S rRNA gene sequences revealed that strain $UR11^T$ was a member of the genus Flavobacterium. Strain $UR11^T$ shared close similarity with F. jejuensis $EC11^T$ (98.0%) F. jumunjinense $HME7102^T$ (96.1%), F. haoranii $LQY-7^T$ (95.3%), F. dongtanense $LW30^T$ (95.1%), and F. ahnfeltiae 10Alg $130^T$(94.9%). The major fatty acids (>5%) were $iso-C_{15:0}$ (33.9%), $iso-C_{15:1}$ G (12.4%), $iso-C_{17:0}$ 3-OH (9.0%), $isoC_{16:0}$ (7.0%) and $iso-C_{15:0}$ 3-OH (6.3%). The major polar lipids were phosphatidylethanolamine, seven unknown aminolipids, two unknown aminopolarlipids and two unknown lipids. DNA-DNA hybridization value was 58% at strain $UR11^T$ with F. jejuensis $EC11^T$. Based on phenotypic, chemotaxonomic and phylogenetic evidence, strain $UR11^T$ represents a novel species of the genus Flavobacterium, for which the name Flavobacterium jocheonensis sp. nov. is proposed. The type strain is Flavobacterium jocheonensis is $UR11^T$ (=KCTC $52377^T$ =JCM $31512^T$).

• 한국미생물·생명공학회지
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• 제47권3호
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• pp.412-422
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• 2019

The present study reports the morphological and molecular characterization of the fungal strain, CMSS06 and evaluates its raw starch hydrolyzing ability in four different agricultural substrates (rice bran, banana peel, cassava tubers, and coconut water). The potential use of each agricultural substrate to replace the expensive fermentation media was evaluated with six different fermentation media: rice bran (RB), banana peel (BP), cassava starch (CS), cassava in coconut water (CSCW), cassava in modified coconut water (CMCW), and pure Coconut water (CW). The fungal strain CMSS06 was identified as Thielaviopsis ethacetica by the analysis of the ITS sequences. The T. ethacetica alpha amylase enzyme exhibited maximum alpha amylase activity at 72 h, pH 7.0, and $40^{\circ}C$ on soluble starch. This species resulted in the highest enzyme activity (mU/ml) of 26.06, 10.89, 58.82, 14.2, and 54.67 with the RB, BP, CS, CSCW, and CMCW fermentation media, respectively. The results indicate that CS can be used as a carbon substrate and CMCW can be used to accelerate the fermentation by T. ethacetica. The enzyme was partially purified by 40-60% ammonium sulphate fraction, and it showed total enzyme activity, total protein content, specific activity, purification fold, and a recovery of 2400 mU, 30 mg, 80 mU/mg, 2.7, and 71.1%, respectively. The molecular mass of the T. ethacetica alpha amylase was estimated on SDS-PAGE, and two bands around 50 kDa and 70 kDa were identified. The present study implies that T. ethacetica can produce alpha amylase, and it can be used to hydrolyze raw starch during the fermentation processes.

• Journal of Microbiology and Biotechnology
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• 제29권5호
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• pp.696-703
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• 2019

Cronobacter sakazakii is an opportunistic pathogen causing serious infections in neonates. In this study, a bacteriophage ${\Phi}CS01$, which infects C. sakazakii, was isolated from swine feces and its morphology, growth parameters, and genomic analysis were investigated. Transmission electron microscopy revealed that ${\Phi}CS01$ has a spherical head and is 65.74 nm in diameter with a 98.75 nm contracted tail, suggesting that it belongs to the family Myoviridae. The major viral proteins are approximately 71 kDa and 64 kDa in size. The latent period of ${\Phi}CS01$ was shown to be 60 min, and the burst size was 90.7 pfu (plaque-forming units)/infected cell. Bacteriophage ${\Phi}CS01$ was stable at $4-60^{\circ}C$ for 1 h and lost infectivity after 1 h of heating at $70^{\circ}C$. Infectivity remained unaffected at pH 4-9 for 2 h, while the bacteriophage was inactivated at pH <3 or >10. The double-stranded ${\Phi}CS01$ DNA genome consists of 48,195 base pairs, with 75 predicted open reading frames. Phylogenetic analysis is closely related to that of the previously reported C. sakazakii phage ESP2949-1. The newly isolated ${\Phi}CS01$ shows infectivity in the host bacterium C. sakazakii, indicating that it may be a promising alternative to antibacterial agents for the removal of C. sakazakii from powdered infant formulas.

• 대한핵의학회지
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• 제25권2호
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• pp.227-236
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• 1991

Background: The evaluation of individual renal function is important to diagnosis and follow-up of various diseases. Ureteral catheterization of each kidney has been widely used for this purpose, but this method had some technical difficulty, frequent complications and much restriction in reapplication. Therefore we tried to applicate radiopharmaceuticals for the evaluation of individual renal function. Methods: We measured 2 hour, 4 hour and 24 hour relative renal uptake of $^{99m}Tc-DMSA$ and relative glomerular filteration rate of $^{99m}Tc-DTPA$ with 59 patients with various renal diseases to determine their usefulness for assessment of individual renal function and to compare correlations between every renal uptake of $^{99m}Tc-DMSA$ and relative glomerular filteration rate. Results: The correlations between 2 hour-, 4 hour- and 24 hour- relative renal uptake of $^{99m}Tc-DMSA$ and relative glomerular filteration rate of $^{99m}Tc-DTPA$ were R=0.9190 (p < 0.001), R: 0.9229 (p<0.001) and R=0.9917 (p<0.001). In acute obstructive uropathy, the correlations at 2 hour and 4 houre were poor as R=0.1812 (p<0.05) and R=0.4923 (p < 0.05), but the correlation at 24 hour was good as R=0.9942 (p<0.001). Conclusions: We concluded that relative renal uptake at 2 hour and 4 hour had good correlation with relative DTPA uptake ratio in the cases without chronic renal failure and obstructive uropathy. Delayed image with 24 hour relative renal uptake $^{99m}Tc-DTPA$ had the best correlation with relative glomerular filteration rate of $^{99m}Tc-DTPA$ and that might be useful in evaluation of chronic renal disease in which showed increased beckground activity or acute obstructive uropathy.

• Journal of Microbiology and Biotechnology
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• 제29권12호
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• pp.1969-1974
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• 2019

A Gram-staining-negative, aerobic, light brown pigment bacterium, designated strain CE80^T was isolated from marine sponge Callyspongia elegans in Jeju Island, Republic of Korea. Strain CE80^T grew optimally at 25℃, in the range of pH 5.0-11.0 (optimum 7.0-8.0), and with 1.0-5.0% NaCl (optimum 1-3% (w/v)). Phylogenetic analysis based on the 16S rRNA gene sequence showed that strain CE80^T belonged to the genus Labrenzia and was closely related to L. suaedae YC6927^T (98.3%), L. alexandrii DFL-11^T (96.6%), L. aggregata IAM 12614^T (96.6%) L. marina mano18^T (96.5%) and L. alba CECT 5094^T (96.2%). The major fatty acids of strain CE80^T were C_18:1 ω7c, and summed feature. The polar lipids were diphosphatidylglycerol, phosphatidylcholine, phosphatidylethanolamine, phosphatidylglycerol, phosphatidylmonomethylethanolamin, one unidentified aminolipid, one phospholipid and four unidentified lipids. The DNA G+C content of strain CE80^T was 55.9 mol%. The major respiratory quinone was Q-10. DNA-DNA relatedness between strain CE80^T and L. suaedae YC6927^T was 56.1±2.8%. On the basis of physiological and biochemical characterization and phylogenetic and chemotaxonomic analysis, strain CE80^T represents a novel species of the Labrenzia, for which the name Labrenzia callyspongiae sp. nov., is proposed. The type strain is CE80^T (=KCTC 42849^T =JCM 31309^T).