• Title/Summary/Keyword: Sole

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Biodegradation of crude oil hydrocarbons by Acinetobacter sp. isolated from activated sludge (활성슬러지에서 단리한 Acinetobacter sp.에 의한 원유탄화수소분해)

  • Dong-Hyuk CHOI;Dong Hoon LEE
    • Journal of Korea Soil Environment Society
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    • v.5 no.1
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    • pp.97-108
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    • 2000
  • A Gram-type negative bacteria that can utilize crude oil as the sole source of carbon and energy was isolated from an activated sludge of a local sewage treatment plant and identified tentatively as belonging to the genus Acinetobacter. The isolate could degrade n-alkanes and unidentified hydrocarbons in crude oil and utilize n-alkanes, hydrophobic substrates, as sole carbon and energy sources. n-Alkanes from tridecane (Cl3) to triacontane (C30) in crude oil were degraded simultaneously with no difference in degradation characteristics between the two close odd and even numbered alkanes in carbon numbers. The linear growth of the isolate and the degradation characteristics of Pr-alkanes suggested that the transport of substrates from the oil phase to the site where the substrates undergo the initial oxidation in microorganism might be the rate limiting in the biodegradation process of crude oil constituents. The remainder fraction of substrates after cultivation was considered to reflect the hydrocarbon inclusions in the cell mass, characteristics in Acinetobacter species, and to control the transport of substrates from crude oil phase. On the basis of the results, the isolate was considered to play an important role in the degradation study of hydrophobic environmental pollutants.

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Metagenome Resource for D-Serine Utilization in a DsdA-Disrupted Escherichia coli

  • Lim, Mi-Young;Lee, Hyo-Jeong;Kim, Pil
    • Journal of Microbiology and Biotechnology
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    • v.21 no.4
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    • pp.374-378
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    • 2011
  • To find alternative genetic resources for D-serine dehydratase (E.C. 4.3.1.18, dsdA) mediating the deamination of D-serine into pyruvate, metagenomic libraries were screened. The chromosomal dsdA gene of a wild-type Escherichia coli W3110 strain was disrupted by inserting the tetracycline resistance gene (tet), using double-crossover, for use as a screening host. The W3110 dsdA::tet strain was not able to grow in a medium containing D-serine as a sole carbon source, whereas wild-type W3110 and the complement W3110 dsdA::tet strain containing a dsdA-expression plasmid were able to grow. After introducing metagenome libraries into the screening host, a strain containing a 40-kb DNA fragment obtained from the metagenomic souce derived from a compost was selected based on its capability to grow on the agar plate containing D-serine as a sole carbon source. For identification of the genetic resource responsible for the D-serine degrading capability, transposon-${\mu}$ was randomly inserted into the 40-kb metagenome. Two strains that had lost their D-serine degrading ability were negatively selected, and the two 6-kb contigs responsible for the D-serine degrading capability were sequenced and deposited (GenBank code: HQ829474.1 and HQ829475.1). Therefore, new alternative genetic resources for D-serine dehydratase was found from the metagenomic resource, and the corresponding ORFs are discussed.

A study on the traceability and uncertainty of skin hydration measurement on the sole of the foot

  • Yang, Gi-Young;Choi, Ji-Won;Chae, Han;Lee, Byung-Ryul
    • The Journal of Korean Medicine
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    • v.38 no.4
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    • pp.55-61
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    • 2017
  • Objectives: In order to accurately measure skin moisture and accumulate normal skin moisture data, analyzing the uncertainty of the skin moisture measurement and establishing standard reference data is essential. It helps to evaluate the skin's condition and has great significance in diagnosis and treatment. In this study, the traceability of the equipment and the uncertainty of the results were analyzed for their potential use in the field of Korean medicine. The data was collected measuring skin moisture on the sole of the foot. Methods: One professional measured the moisture of the adult male's foot 10 times following a determined protocol. The standard uncertainty of repeated measurements was calculated from the mean value of 10 repeated measurements. Ten trainee participants also measured the adult male's foot following a determined protocol. The standard uncertainty by tester was calculated from the value of repeated measurements. Results: As a result of analyzing the difference between the mean and standard uncertainties in both the expert and trainees, it was confirmed that the variance in this study did not satisfy the normal distribution. In addition, the Mann-Whitney U-test was carried out, and it was found that there was no significant difference in the measured values of the two groups. The authorized uncertainty of measurements and traceability of all the equipment was not confirmed. Conclusions: This paper establishes the basis for later measurement-equipment research to provide the objective indicators to approach the dryness of plantar skin from dehydration, the Korean medicine perspective.

Effect of Stepped Pattern of Feed Intake Using Rice Straw as Roughage Source on Regulation of Growth, Reproduction and Lactation in Dairy Heifers

  • Jin, M.G.;Lee, H.G.;Lee, H.J.;Hong, Z.S.;Wang, J.H.;Yin, Y.H.;Jin, R.H.;Cho, K.K.;Choi, Y.J.
    • Asian-Australasian Journal of Animal Sciences
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    • v.17 no.6
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    • pp.794-798
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    • 2004
  • An attempt was made to improve the efficiency of growth and lactation performance of dairy heifers subjected to a stair-step growth scheme using rice straw as the sole roughage source. Twenty-four young Holstein heifers were randomly assigned to either control or test group. The control diet met the National Research Council (NRC) requirement, with heifers calving at 24 to 26 mo of age. The test group was individually fed according to a schedule of 3, 2, 4, 2, 5 and 2 mo in which feed intake was alternately 20% below or 25% above the NRC requirements. Heifers on the stair-step growth pattern gained more body weight and consumed less dry matter (10.80 and 11.22%, respectively), resulting an increasing growth efficiency compared with the control. Body condition, first estrus, first conception, services per conception and calving difficulty (data not shown) were not affected. Milk yield of the test group was 8.5% higher than that of the control group. During the early lactation period, the milk yield was significantly higher in the stair-step group than in that of the control group (p<0.05). Milk composition was not affected by compensatory growth induced by the stair-step scheme. Also, weight at calving and calf growth performance was not affected by stair-step growth. The results indicate that using rice straw as a sole roughage source in a stair-step compensatory growth scheme can contribute to the improvement of growth efficiency and early lactation performance.

Effect of Restricted and Ad libitum Feeding of Urea Molasses Liquid Diet (UMLD) on the Performance of Adult Crossbred Cattle

  • Mehra, U.R.;Verma, A.K.;Dass, R.S.
    • Asian-Australasian Journal of Animal Sciences
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    • v.11 no.1
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    • pp.30-34
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    • 1998
  • To compare response of feeding concentrate mixtere and wheat straw (Group I) with either urea molasses liquid diet (UMLD) as sole ration (group II) or UMLD (similar to protein equivalent of concentrate mixture) plus wheat straw (group III) on intake and utilisation of nutrients and overall performance, twelve crossbred adult male cattle (Holstein Friesian ${\times}$ Hariana) aged about 2.5 years and weighing 342 kg were randomly allotted into three equal groups following completely randomised design and fed respective diets for a period of 60 days. Thereafter, a metabolism trial of seven days duration was conducted to assess nutrient utilisation and nitrogen balance. Animals fed UMLD as sole ration consumed significantly (p < 0.01) less amount of most of the nutrients as compared to other two groups, except crude protein, intake of which was higher in this group but it was comparable between II and III and III and I. On the other hand, digestibilities of nutrients were higher (p < 0.01) in group II, though it was comparable between other two groups, except ADF, the digestibility of which was lower in group II. Inspite of positive nitrogen balance in all the three groups, being significantly (p < 0.01) higher in group I, animals of group II and III lost their body weight especially to the utmost extent in group II, although the amount of energy (TDN) intake were similar statistically. Results indicate that during a scarcity period and economic compulsions, feeding of UMLD can be practised to replace only concentrate mixture from the maintenance ration of adult crossbred cattle for shorter duration as roughage part seems to be essential for the normal functioning of the rumen microbes and overall performance of the animals.

Bioavailability of Iron-fortified Whey Protein Concentrate in Iron-deficient Rats

  • Nakano, Tomoki;Goto, Tomomi;Nakaji, Tarushige;Aoki, Takayoshi
    • Asian-Australasian Journal of Animal Sciences
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    • v.20 no.7
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    • pp.1120-1126
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    • 2007
  • An iron-fortified whey protein concentrate (Fe-WPC) was prepared by addition of ferric chloride to concentrated whey. A large part of the iron in the Fe-WPC existed as complexes with proteins such as ${\beta}$-lactoglobulin. The bioavailability of iron from Fe-WPC was evaluated using iron-deficient rats, in comparison with heme iron. Rats were separated into a control group and an iron-deficiency group. Rats in the control group were given the standard diet containing ferrous sulfate as the source of iron throughout the experimental feeding period. Rats in the iron-deficiency group were made anemic by feeding on an Fe-deficient diet without any added iron for 3 wk. After the iron-deficiency period, the iron-deficiency group was separated into an Fe-WPC group and a heme iron group fed Fe-WPC and hemin as the sole source of iron, respectively. The hemoglobin content, iron content in liver, hemoglobin regeneration efficiency (HRE) and apparent iron absorption rate were examined when iron-deficient rats were fed either Fe-WPC or hemin as the sole source of iron for 20 d. Hemoglobin content was significantly higher in the rats fed the Fe-WPC diet than in rats fed the hemin diet. HRE in rats fed the Fe-WPC diet was significantly higher than in rats fed the hemin diet. The apparent iron absorption rate in rats fed the Fe-WPC diet tended to be higher than in rats fed the hemin diet (p = 0.054). The solubility of iron in the small intestine of rats at 2.5 h after ingestion of the Fe-WPC diet was approximately twice that of rats fed the hemin diet. These results indicated that the iron bioavailability of Fe-WPC was higher than that of hemin, which seemed due, in part, to the different iron solubility in the intestine.

Genetic and Phenotypic Diversity of Fenitrothion-Degrading Bacteria Isolated from Soils

  • Kim, Kyung-Duk;Ahn, Jae-Hyung;Kim, Tae-Sung;Park, Seong-Chan;Seong, Chi-Nam;Song, Hong-Gyu;Ka, Jong-Ok
    • Journal of Microbiology and Biotechnology
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    • v.19 no.2
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    • pp.113-120
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    • 2009
  • Twenty-seven fenitrothion-degrading bacteria were isolated from different soils, and their genetic and phenotypic characteristics were investigated. Analysis of the 16S rDNA sequence showed that the isolates were related to members of the genera Burkholderia, Pseudomonas, Sphingomonas, Cupriavidus, Corynebacterium, and Arthrobacter. Among the 27 isolates, 12 different chromosomal DNA fingerprinting patterns were obtained by polymerase chain reaction(PCR) amplification of repetitive extra genic palindromic(REP) sequences. The isolates were able to utilize fenitrothion as a sole source of carbon and energy, producing 3-methyl-4-nitrophenol as the intermediate metabolite during the complete degradation of fenitrothion. Twenty-two of 27 isolates were able to degrade parathion, methyl-parathion, and p-nitrophenol but only strain BS2 could degrade EPN(O-ethyl-O-p-nitrophenyl phenylphosphorothioate) as a sole source of carbon and energy for growth. Eighteen of the 27 isolates had plasmids. When analyzed with PCR amplification and dot-blotting hybridization using various specific primers targeted to the organophosphorus pesticide hydrolase genes of the previously reported isolates, none of the isolates showed positive signals, suggesting that the corresponding genes of our isolates had no significant sequence homology with those of the previously isolated organophosphate pesticide-degrading bacteria.

Characterization of Hexane Biodegradation by Rhodococcus sp. EH741 (Rhodococcus sp. EH741에 의한 Hexane 생분해 특성)

  • Lee, Eun-Hee;Cho, Kyung-Suk
    • Journal of Korean Society of Environmental Engineers
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    • v.28 no.2
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    • pp.144-149
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    • 2006
  • As a strain EH741, having an excellent hexane degradability, was isolated from bacterial consortium using hexane as a sole carbon and energy source. EH741 was identified as a Rhodococcus sp. and the addition of a surfactant Pluronic F68(PF68), for increasing hexane solubility couldn't enhance the specific growth rate of the isolate EH741 n the mineral salt medium supplemented with hexane as a sole carbon source(hexane-BH medium). In the hexane-BH medium, the maximum specific growth rate(${\mu}_{max}$) of this strain was $0.04h^{-1}$, and the maximum hexane degradation rate($V_{max}$) and saturation constant($K_s$) were$161{\mu}mol{\cdot}g-DCW^{-1}{\cdot}h^{-1}$ and 10.5 mM, respectively. Rhodococcus sp. EH741 was one of excellent microorgamisms for hexane biodegradation processes.

Egg Development and Morphological Change of Larvae and Juveniles of the Sakhalin Sole Limanda sakhalinensis (사할린가자미(Limanda sakhalinensis)의 난발생 과정 및 자치어 형태발달)

  • Han, Kyeong-Ho;Na, Hae-Choon;Park, Ae-Jeon;Park, Jae-Min
    • Korean Journal of Fisheries and Aquatic Sciences
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    • v.50 no.3
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    • pp.287-295
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    • 2017
  • Egg development and morphological change of larvae of the Sakhalin sole Limanda sakhalinensis were studied by observing specimens obtained in a rearing experiment from fertilized eggs to the juvenile stage. The wild broodstock was collected in January 2010 and kept in a circular water tank (${\O}1.5{\times}1m$) at a temperature of $14.5{\pm}0.5^{\circ}C$. Fertilized eggs ranged from 0.72 to 0.82 mm ($0.77{\pm}0.07mm$, $mean{\pm}SD$) in diameter. The eggs were spherical, transparent and adhesive demersal. The egg yolk was divided from the oocyte 10 min after fertilization (AF), and an embryo was formed in 36 h AF. More than 50% of the eggs hatched within 133 h AF. The mouth and anus did not open until $3.5{\pm}0.25mm$ total length (TL). At 4, days after hatching (AH), the fish became larvae 3.7 to 4.2 mm ($4.0{\pm}0.36mm\;TL$), yolk absorption was completed and the mouth began to open. The left eye moved upward and the nostril moved to the right at 39 days AH. These post-larvae ranged from 8.0 to 9.9 mm TL ($8.9{\pm}1.33mm\;TL$). At 50 days AH, the fish became juveniles ($12.4{\pm}1.20mm\;TL$) There were 70-72 dorsal fin rays, 55-56 anal fin rays, 11 pectoral fin rays, and 6 ventral fin rays and the juveniles adopted a benthic life.

Influence of Drying Methods on Measurement of Hydration Degree of Hydraulic Inorganic Materials: 1) Ordinary Portland cement paste and mortar (수경성 무기재료의 수화도 측정에 대한 건조방법의 영향: 1) 보통 포틀랜드 시멘트 페이스트 및 모르타르)

  • Lee, Hyo Kyoung;Kim, Hyeong-Ki
    • Resources Recycling
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    • v.27 no.1
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    • pp.92-105
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    • 2018
  • The present study was carried out to find a suitable drying method for measuring non-evaporable water contents of various hydraulic inorganic materials. In Part 1 of the paper, the case Ordinary Portland cement is discussed. Various drying methods including vacuum and oven drying, and an ignition, were used for the OPC paste and mortar having different w/c. The sole vacuum drying under room temperature led a fluctuation on measurement of hydration degree, while the sole oven drying also yielded unwanted hydration promotion at the early age. A combination of the vacuum and oven drying was considered as a suitable drying method for the OPC case.