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Effects of Salicylate and Glucose on Biodegradation of Phenanthrene by Burkholderia cepacia PM07

  • LEE DAE SUNG;LEE MIN WOO;WOO SEUNG HAN;PARK JONG MOON
    • Journal of Microbiology and Biotechnology
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    • v.15 no.4
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    • pp.859-865
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    • 2005
  • The stimulatory effects of exogenous salicylate as a pathway inducer on phenanthrene biodegradation were investigated using Burkholderia cepacia PM07. The phenanthrene degradation rate was greatly enhanced by increasing the salicylate additions, and the maximum rate was 19.6 mg $I^{-1}\;d^{-1}$ with the addition of 200 mg $I^{-1}$ of salicylate, 3.5 times higher than that (5.6 mg $I^{-1}\;d^{-1}$) without the addition of salicylate. The degradation rate was decreased at higher concentrations of salicylate (above 500 mg$I^{-1}$), and cell growth was significantly inhibited. The phenanthrene degradation was not affected by increasing glucose up to 2 g $I^{-1}$, although dramatic microbial growth was obtained. The stimulatory effect of exogenous salicylate decreased in the presence of glucose. After the addition of 200 mg $I^{-1}$ of salicylate, approximately $60\%$ of the initial phenanthrene (50 mg $I^{-1}$) was degraded after 96 h. However, with extra addition of 200 mg $I^{-1}$ of glucose, the phenanthrene degradation rate decreased, and only $18.5\%$ of the initial phenanthrene was degraded.

Plasmid-associated Bacteriocin Production by Leuconostoc sp. LAB145-3A Isolated from Kimchi

  • Choi, Yeon-Ok;Ahn, Cheol
    • Journal of Microbiology and Biotechnology
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    • v.7 no.6
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    • pp.409-416
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    • 1997
  • Leuconostoc sp. LAB145-3A isolated from kimchi produced a bacteriocin which was active against food pathogens, such as Listeria monocytogenes, Enterococcus faecalis, and E. faecium. Bacteriocin production occurred during the early exponential phase of growth and was stable upto the late stationary phase of growth. Optimum conditions for bacteriocin production were $37^{\circ}C$ with an initial pH of 7.0. The bacteriocin of LAB145-3A was sensitive to proteases, but stable for solvents, pH change and heat treatment. It was stable even at autoclaving temperature for 15 min. The bacteriocin exhibited a bactericidal mode of action against Lactobacillus curvatus LAB170-12. The bacteriocin produced by Leuconostoc sp. LAB145-3A was purified by CM-cellulose cation exchange column chromatography and Sephadex G-50 gel filtration. The purification resulted in an approximate 10,000-fold increase in the specific activity. Approximately 4% of the initial activity was recovered. Purified bacteriocin exhibited a single band on the SDS-PAGE with an apparent molecular weight of 4,400 daltons. This bacteriocin was named leucocin K. Leuconostoc sp. LAB145-3A had two residential plasmids with molecular sizes of 23 kb and 48 kb. A comparison of plasmid profiles between LAB145-3A and its mutants revealed that the 23 kb plasmid (pCA23) was responsible for bacteriocin production and immunity to the bacteriocin in Leuconostoc sp. LAB145-3A.

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The Fermentation Characteristics of Saccharomyces cerevisiae F38-1 a Thermotolerant Yeast Isolated for Fuel Alcohol Production at Elevated Temperature (연료용 알콜의 고온발효를 위해 분리한 고온성 효모균주 Saccharomyces cerevisiae F38-1의 발효 특성)

  • 김재완;김상헌;진익렬
    • Microbiology and Biotechnology Letters
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    • v.23 no.5
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    • pp.624-631
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    • 1995
  • The fermentation characteristics of Saccharomyces cerevisiae F38-1, a newly isolated thermotolerant yeast strain from a high temperature environment have been studied using a fermentation medium containing 20% glucose, 0.2% yeast extract, 0.2% polypeptone, 0.3% (NH$_{4}$)$_{2}$SO$_{4}$, 0.1% KH$_{2}$PO$_{4}$, and 0.2% MgSO$_{4}$ without shaking at 30$\circ$C to 43$\circ$C for 5 days. The fermentability was over 90% at 30$\circ$C, 88% at 37$\circ$C, 77% at 40$\circ$C and 30% at 43$\circ$C. A similar fermentation result was obtained at pH between 4 and 6 at 30$\circ$C and 40$\circ$C. Aeration stimulated the growth of the strain at the beginning of the fermentation, but it reduced alcohol production at the end of alcohol fermentation. Optimal glucose concentration was determined to be between 18 and 22% at 40$\circ$C as well as 30$\circ$C, but the growth was inhibited at the glucose concentration of over 30%. A fermentability of over 90% was observed at 40$\circ$C in 2 days when the medium was supplemented by 2% yeast extract. A higher inoculum size increased the initial fermentation rate, but not the fermentation. A fermentability of over 90% was achieved in 2 days at 40$\circ$C in a fermentor experiment using an optimized medium containing 20% glucose and 1% yeast extract.

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Cultural Characteristics of A Medicinal Mushroom, Phellinus linteus

  • Hong, In-Pyo;Jung, I-Yeon;Nam, Sung-Hee;Park, Jeong-Sik;Cho, Joon-Hyeong;Lee, Min-Woong;Guo, Shun-Xing
    • Mycobiology
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    • v.30 no.4
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    • pp.208-212
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    • 2002
  • For comparison of mycelial colonization of Phellinus linteus on logs, several techniques of inoculation were tested; sterilized short log inoculation, drilling inoculation and log-end sandwich inoculation. The mycelial colonization of P. linteus on logs was good in the treatment of sterilized short log inoculation, but poor in the traditional methods such as drilling inoculation and log-end sandwich inoculation. The initial mycelial growth and the full mycelial colonization of P. linteus in logs were the best in case of 20 cm logs under the condition of 42% moisture content. Also, the initial mycelial growth of P. linteus was accelerated over 12 hours of sterilization. Burying method of logs after $5{\sim}6$ months of incubation was the best for formation of basidiocarps of P. linteus. The formation of fruiting body of P. linteus was quite good in the cultivation house at $31{\sim}35^{\circ}C$ and over 96% of relative humidity.

Relationship between Concentration of Alcian Blue and Mechanical Properties on High Current Density Copper Electroplating (고전류밀도 구리도금공정에서 알시안블루(Alcian Blue) 농도와 기계적 특성과의 상관관계)

  • Woo, Tae-Gyu
    • Korean Journal of Materials Research
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    • v.30 no.4
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    • pp.160-168
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    • 2020
  • The current density in copper electroplating is directly related with the productivity; then, to increase the productivity, an increase in current density is required. This study is based on an analysis of changes in surface characteristics and mechanical properties by applying the addition of Alcian Blue (AB, C56H68Cl4CuN16S4). The amount of Alcian Blue in the electrolytes is changed from 0 to 100 ppm. When Alcian Blue is added at 20 ppm, a seed layer is formed homogeneously on the surface at the initial stage of nucleation. However, crystals electroplated in electrolytes with more than 40 ppm of Alcian Blue are observed to have growth in the vertical direction on the surface and the shapes are like pyramids. This tendency of initial nucleation formation causes protrusions when the thickness of copper foil is 12 ㎛. Thereafter, a lot of extrusions are observed on the group of 100 ppm Alcian Blue. Tensile strength of groups with added Alcian Blue increased by more than 140% compare to no-addition group, but elongation is reduced. These results are due to the decrease of crystal size and changes of prior crystal growth plane from (111) and (200) to (220) due to Alcian Blue.

A Study on Adolescents' Internalizing and Externalizing Problem Behaviors and Related Variables in Transition with Latent Growth Model (잠재성장모형을 활용한 청소년 전환기 내면화 및 외현화 문제행동과 관련변인에 관한 연구)

  • Kim, YeonJu;Lee, Jimin
    • Journal of Families and Better Life
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    • v.33 no.1
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    • pp.1-17
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    • 2015
  • This study investigated how variables of internalizing and externalizing problematic behaviors change according to gender and as time passes by and how the variables influence adolescent problematic behaviors. The variables selected for the analysis are personal variables, parent variables, peer and school variables, and community variables. longitudinal data collected for 4 years from the Korea Youth Panel Survey(KYPS) were utilized for the analysis. Data were collected initially from 2,707 fifth grade elementary students in 2005 and they were traced until 2008. The final respondents were 2,448 students. The findings are as follows. Frist, the statistical significance was found in changes of problematic behavioral variables in terms of the gender difference. Second, variables, such as self-esteem and self-control are negatively correlated to the problematic behaviors and stress level is strongly positively correlated to the behaviors. Third, the study pressure and peer attachment level are correlated to the initial value of internalizing problematic behaviors. In conclusion, given that more statistical significances were found at initial values than the change rates among variables, early intervention is important in addressing adolescent problematic behaviors.

Factors Affecting Primary Cultures of Abalone Haliotis discus hannai Ovary-dissociated Cells and General Culture Aspects

  • Ryu, Jun Hyung;Nam, Yoon Kwon;Gong, Seung Pyo
    • Fisheries and Aquatic Sciences
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    • v.18 no.1
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    • pp.81-88
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    • 2015
  • We investigated factors affecting primary cultures of Pacific abalone Haliotis discus hannai ovary-dissociated cells to identify general aspects of their early-phase culture. Ninety-seven cell populations derived from 30 individuals were cultured in different media with varying compositions of medium supplements, and initial attachment, subculture, and survival for ${\geq}10$ weeks were assessed according to medium composition and individual. We also examined the time required for subculture and the rate of cell death according to both culturing period and passage number within 10 weeks. A lack of fetal bovine serum (FBS) and hemolymph significantly inhibited the growth of cultured cells, while we detected no significant effect of medium composition on initial cell attachment. Through data reallocation, with the omission of data from cell populations cultured in FBS-free and hemolymph-free media, we showed that growth inhibition was also affected by individual differences among the abalones used. During the culture, we observed four different types of cell morphology. Moreover, considerable time was required for subculture-18.4 and 19.5 days for first and second subcultures, respectively-and cell death did not occur within 30 days or for passage 0. Our results will provide valuable information for developing universal cell culturing guidelines in abalone species and suggest the feasibility of culturing abalone ovary-dissociated cells.

Effects of Plant Age Inoculum Concentration and Inoculation Method on Root Gall Development of Clubroot Disease of Chinese Cabbage Caused by Planmodiophora brassicae (배추무사마병의 뿌리혹 형성에 미치는 묘령, 접종원 농도 및 접종방법의 영향)

  • 김충회
    • Plant Disease and Agriculture
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    • v.5 no.2
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    • pp.90-94
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    • 1999
  • Effect of inoculum concentration inoculation method and plant age on development of clubroot disease of Chinese cabbage seedling were examined in growth chambers. Root galls were developed at the concentration of 105 resting spore or above per ml of incoulum and as the inoculum concentration became higher rate of development of root galls was faster. In the plants with root gall development fresh weight of above ground parts was reduced to 30-44% of that of healthy plants but root weight increased by 4-10 times. Growth of diseased plants was greatly reduced as compared to healthy plants. Planting in the diseased soil as a inoculation method was most effective for disease development showing uniform infections but time of initial root gall development was delayed by root soaking inoculation. Some plants inoculated by soil drenching method did not develop root galls. However root gall enlargement after its initial formation did not differ greatly among inoculation methods. Nine-day-old seedlings showed poor development of root gall but 16-days-old seedlings was found to be most adequate for inoculation for gall development.

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A Study on the Human Growth Hormone Response Following Electro Convulsion Therapy (전기-경련 시술후의 혈장 HGH 반응)

  • Kim, Dong-Ju;Sung, Ho-Kyung;Rhee, Sang-Don
    • The Korean Journal of Physiology
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    • v.10 no.1
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    • pp.67-71
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    • 1976
  • Effect of Electro Convulsion Therapy (ECT) on the Human Growth Hormone (HGH) response was observed in 32 cases of various mental illness. The patients were fasting overnight and ECT was induced in the morning by application of $90{\sim}120V$ for a period of $0.1{\sim}0.5\;sec$. In all patients, venous blood samples were taken prior to simultaneously with 1 and 4 hours after the ECT. Plasma was immediately seperated and stored in $-20^{\circ}C$ refrigerator. HGH concentrantion was determined by means of radioimmunoassay Results were as follows: 1. Application of electric current was not followed by a significant change in mean plasma HGH of 52 cases. 2 Increases of plasma HGH following ECT were observed in about half cases showing low initial level but in 20 other cases with high initial level of plasma HGH, reasonable decreases after therapy were not found. 3. Plasma concentration of HGH one hour after application of current were always higher than just after the current. 4. There were no differences between HGH responses to a 1st, 2nd or 5th ECT. 5. Discussions were made on the possible modification of HGH response following ECT by the autoregulatory control mechanism.

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The Impact of The Sales Scale to Fisheries Products Processing Business on Primary Fisheries Cooperatives in Korea (수협 회원조합의 매출액 규모가 수산물 가공사업에 미치는 영향)

  • Park, Joon-Mo
    • The Journal of Fisheries Business Administration
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    • v.46 no.3
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    • pp.1-14
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    • 2015
  • This study aims to examine factors affecting the seafood processing business of primary cooperatives. For this purpose, I divided primary cooperatives that participate to seafood processing business into three group by sales scale. And then analyzed survey results for the four items that might be affecting the seafood processing business, type of seafood processing methods, HACCP certification status, distribution channels, processing difficulties during project implementation, etc. The result offers four implications. First, It is desirable to reduce the burden of the initial investment by leveraging the consignment process at the initial entry to seafood processing business. Second, HACCP certification is essential factor in order to promote seafood processing business as a long-term economic business. Third, To the steady growth of the seafood processing business, it is important to secure fixed large customers, as well as a individual customer. Fourth, For the continued growth of the seafood processing business it should be approached differently by way of sales, when the National Federation of Fisheries Cooperatives support to primary cooperatives.