• 제목/요약/키워드: biological cause

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Potentials for Biological Control of Blue Stain on Woods Caused by Ophiostomatoid Fungi

  • Lee, Jong-Kyu;Oh, Eun-Sung
    • The Plant Pathology Journal
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    • 제16권4호
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    • pp.200-205
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    • 2000
  • Biological control of blue stain fungi, such as Ophiostoma and Leptographium spp., that reduce the quality of logs and cause economic losses in wood product industry, was carried out in laboratory and field trials by a colorless strain of Ophiostoma quercus, BSFcs-1. Inoculation of pine wood chips with the colorless strain 1 wk before inoculating wild-type strain demonstrated that BSFcs-1 colonized wood chips and excluded blue stain fungi from being established. Efficacy of BSFcs-1 was compared with colorless strain of O. piliferum, which is commercially available under the trade name of Cartapip. Inoculation of pine wood logs with the colorless strain 1 wk before inoculating wild-type strain of blue stain in isolated wood chips, while O. quercus and O. floccosum colonized 0% and 17%, respectively. Simultaneous inoculation of logs with the colorless and wild-type strains resulted in decreased colonization (28%) by BSFcs-1, but increased colonization by O. quercus (185) and O. floccosum (29%). On the other hand, BSFcs-1 and wild-type strain alone colonized 75% and 71%, respectively. Treatment of the surface of log ends with mycelial suspension of BSFcs-1 after cutting also showed good control of blue stain fungi in a pine forest stands.

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생물테러와 환경소독 (Bioterrorism and Environmental Decontamination)

  • 정우동;문성민;윤제용
    • 대한환경공학회지
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    • 제29권9호
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    • pp.1051-1059
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    • 2007
  • 병원성 미생물을 이용하여 인명살상과 사회적 혼란을 야기하는 생물학적 테러에 대응하기 위한 여러 방안 중에서 사후조치로써의 환경에서 생물무기 제독(환경소독)은 매우 중요하다. 이러한 상황에 대한 현재 우리의 환경소독 방법은 대부분 소독제를 물과 반응시킨 고농도의 수용액을 이용한 소독 방법을 적용하고 있다. 생물테러와 같은 고위험 병원성 미생물에 오염된 실내공간을 완벽하게 소독하거나 군사적인 목적의 제독작전을 위해서는 수용액을 이용한 표면의 제독방법과 더불어 가스 상의 멸균제를 혼합한 공간제독이 병행되어야 할 것이다. 이 글에서는 생물테러라는 특수한 상황을 전제로 하여 실내소독에 대한 현행 환경소독의 문제점과 해외 동향을 분석해보고 앞으로의 발전을 위한 제언을 하였다.

The Anticoagulant Fraction from the Leaves of Diospyros Kaki L. Has an Antithrombotic Activity

  • Sa You Seon;Kim Soo-Jin;Choi Hye-Seon
    • Archives of Pharmacal Research
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    • 제28권6호
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    • pp.667-674
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    • 2005
  • The leaves of Persimmon (Diospyros kaki L.) has long been used for tea in Korea since it was thought to be effective against hypertension. An anticoagulant fraction was purified through gel filtration G-100, hydrophobic, gel filtration G-150, and FPLC, Phenyl superpose column chromatographies. The purified fraction was homogenous and its Mr was estimated 10,000 Da by gel filtration and SDS-PAGE. The purified fraction was sensitive to treatment of subtilisin B, but not to heat and its activity was not changed after periodate oxidation, indicating that the activity was not due to carbohydrates. It delayed thrombin time (TT), activated partial thromboplastin time (APTT), and prothrombin time (PT) using human plasma. TT was more sensitive than APTT and PT, suggesting that the anticoagulant activity may be caused by a degradation or a defect of fibrin or thrombin. It did not cause the hydrolysis of fibrin after incubation. However, it inhibited thrombin-catalyzed fibrin formation with a competitive inhibition pattern. These results indicate that it may be an antithrombotic agent and that it is bound to fibrinogen binding sites of thrombin.

Design of Optical Biological Sensor for Phycocyanin Parameters Measurement using Fluorescence Technique

  • Lee, Sung Hwa;Mariappan, Vinayagam;Won, Dong Chan;Ann, Myungsuk;Yang, Seungyoun
    • International journal of advanced smart convergence
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    • 제5권2호
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    • pp.73-79
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    • 2016
  • Remote sensing and measurement are of paramount importance of providing information on the state of water quality in water bodies. The formation and growth of cyanobacteria is of serious concern to in land aquatic life forms and human life. The main cause of water quality deterioration stems from anthropogenic induced eutrophication. The goal of this research to quantify and determine the spatial distribution of cyanobacteria concentration in the water using remote sensing technique. The standard approach to measure water quality based on the direct measurement of the fluorescence of the chlorophyll a in the living algal cells and the same approach used to detect the phycobilin pigments found in blue-green algae (a.k.a. cyanobacteria), phycocyanin and phycoerythrin. This paper propose the emerging sensor design to measure the water quality based on the optical analysis by fluorescence of the phycocyanin pigment. In this research, we developed an method to sense and quantify to derive phycocyanin intensity index for estimating cyanobacteria concentrations. The development of the index was based on the reflectance difference between visible light band 620nm and 665nm. As a result of research this paper presents, an optical biological sensor design information to measure the Phycocyanin parameters in water content.

소수성화학물질의 생물축적과 기저독성: 분자크기, 반응속도, 화학적 활성도에 따른 제약 (Bioaccumulation and Baseline Toxicity of Hydrophobic Chemicals: Molecular Size Cutoff, Kinetic Limitations, and Chemical Activity Cut-off)

  • 권정환
    • Environmental Analysis Health and Toxicology
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    • 제23권2호
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    • pp.67-77
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    • 2008
  • It has been observed that the linear relationship between the logarithm of bioconcentration factor (log BCF) of highly hydrophobic chemicals and their log $K_{ow}$ breaks when log $K_{ow}$ becomes greater than 6.0. Consequently, super hydrophobic chemicals were not thought to cause baseline toxicity as a single compound. Researchers often call this phenomenon as "hydrophobicity cutoff" meaning that bioconcentration or corresponding baseline toxicity has a certain cutoff at high log $K_{ow}$ value of hydrophobic organic pollutants. The underlying assumption is that the increased molecular size with increasing hydrophobicity prohibits highly hydrophobic compounds from crossing biological membranes. However, there are debates among scientists about mechanisms and at which log $K_{ow}$ this phenomenon occurs. This paper reviews three hypotheses to explain observed "cutoff": steric effects, kinetic or physiological limitations, and chemical activity cutoff. Although the critical molecular size that makes biological membranes not permeable to hydrophobic organic chemicals is uncertain, size effects in combination with kinetic limitation would explain observed non-linearity between log BCF and log $K_{ow}$. Chemical activity of hydrophobic chemicals generally decreases with increasing melting point at their aqueous solubility. Thus, there may be a chemical activity cutoff of baseline toxicity if there is a critical chemical activity over which baseline effects can be observed.

부레옥잠을 이용한 Clostridium beijerinckii의 Biobutanol 생산 (Production of Biobutanol by Clostridium beijerinckii from Water Hyacinth)

  • 박봉제;박혜민;윤현식
    • KSBB Journal
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    • 제31권1호
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    • pp.79-84
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    • 2016
  • Biofuel has been considered as promising renewable energy to solve various problems that result from increasing usage of fossil fuels since the early 20th century. In terms of chemical and physical properties as fuel, biobutanol has more merits than bioethanol. It could replace gasoline for transportation and industrial demand is increasing significantly. Production of butanol can be achieved by chemical synthesis or by microbial fermentation. The water hyacinth, an aquatic macrophyte, originated from tropical South America but is currently distributed all over the world. Water hyacinth has excellent water purification capacity and it can be utilized as animal feed, organic fertilizer, and biomass feedstock. However, it can cause problems in the rivers and lakes due to its rapid growth and dense mats formation. In this study, the potential of water hyacinth was evaluated as a lignocellulosic biomass feedstock in biobutanol fermentation by using Clostridium beijerinckii. Water hyacinth was converted to water hyacinth hydrolysate medium through pretreatment and saccharification. It was found that productivity of water hyacinth hydrolysate medium on biobutanol production was comparable to general medium.

Biological Control of Oomycete Soilborne Diseases Caused by Phytophthora capsici, Phytophthora infestans, and Phytophthora nicotianae in Solanaceous Crops

  • Elena Volynchikova;Ki Deok Kim
    • Mycobiology
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    • 제50권5호
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    • pp.269-293
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    • 2022
  • Oomycete pathogens that belong to the genus Phytophthora cause devastating diseases in solanaceous crops such as pepper, potato, and tobacco, resulting in crop production losses worldwide. Although the application of fungicides efficiently controls these diseases, it has been shown to trigger negative side effects such as environmental pollution, phytotoxicity, and fungicide resistance in plant pathogens. Therefore, biological control of Phytophthora-induced diseases was proposed as an environmentally sound alternative to conventional chemical control. In this review, progress on biological control of the soilborne oomycete plant pathogens, Phytophthora capsici, Phytophthora infestans, and Phytophthora nicotianae, infecting pepper, potato, and tobacco is described. Bacterial (e.g., Acinetobacter, Bacillus, Chryseobacterium, Paenibacillus, Pseudomonas, and Streptomyces) and fungal (e.g., Trichoderma and arbuscular mycorrhizal fungi) agents, and yeasts (e.g., Aureobasidium, Curvibasidium, and Metschnikowia) have been reported as successful biocontrol agents of Phytophthora pathogens. These microorganisms antagonize Phytophthora spp. via antimicrobial compounds with inhibitory activities against mycelial growth, sporulation, and zoospore germination. They also trigger plant immunity-inducing systemic resistance via several pathways, resulting in enhanced defense responses in their hosts. Along with plant protection, some of the microorganisms promote plant growth, thereby enhancing their beneficial relations with host plants. Although the beneficial effects of the biocontrol microorganisms are acceptable, single applications of antagonistic microorganisms tend to lack consistent efficacy compared with chemical analogues. Therefore, strategies to improve the biocontrol performance of these prominent antagonists are also discussed in this review.

Draft Genome Sequence of Aeromonas caviae Isolated from a Newborn with Acute Haemorrhagic Gastroenteritis

  • Savita Jadhav;Ujjayni Saha;Kunal Dixit;Anjali Kher;Sourav Sen;Nitin Lingayat;Vivekanand Jadhav;Sunil Saroj
    • 한국미생물·생명공학회지
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    • 제51권2호
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    • pp.217-221
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    • 2023
  • Aeromonas spp., are Gram-negative rods that can cause infections in healthy and immunocompromised hosts. The clinical presentation of gastroenteritis varies from mild diarrhoea to shigella-like dysentery to severe cholera-like watery diarrhoea. Here, we report a case of acute hemorrhagic gastroenteritis in a newborn infant by Aeromonas caviae and its draft genome sequence. It is important to reduce the chance of incorrect isolate identification, which could lead to the exclusion of pathogenic Aeromonas spp., from routine laboratory identification in cases of diarrheal diseases. The genome sequence of A. caviae SVJ23 represents a significant step forward in understanding the diversity and pathogenesis, virulence, and antimicrobial resistance profile.

Chemical Indices of Soil Quality: Effects of Heavy Metal Additions

  • Yang, Jae-E.;Choi, Moon-Heon;Lee, Wi-Young;Kim, Jeong-Je;Jung, Yeong-Sang
    • Applied Biological Chemistry
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    • 제41권8호
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    • pp.587-594
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    • 1998
  • The objective of this research was to characterize effects of Cu or Cd additions on chemistry of soil quality indices, such as pH, EC, cation distribution and buffering capacity. Metals were added at rates ranging from 0 to 400 mg $kg^{-1}$ of soil. Soil solution was sequentially extracted from saturated pastes using vacuum. Concentrations of Cu or Cd remaining in soil solutions were very low as compared to those added to the soils, warranting that most of the added metals were recovered as nonavailable fractions. Adsorption of the added metals released cations into soil solution causing increases of ionic strength of soil solution. At metal additions of $200{\sim}400\;mg\;kg^{-1}$, EC of soil solution increased to as much as $2{\sim}4\;m^{-1}$; salinity levels considered high enough to cause detrimental effects on plant production. More divalent cations than monovalent cations were exchanged by Cu or Cd adsorption. The nutrient buffering capacity of soils was decreased due to the metal adsorption and release of cations. pH of soil solution decreased linearly with increasing metal loading rates, with a decrement of up to 1.3 units at 400 mg Cu $kg^{-1}$ addition. Influences of Cu on each of these soil quality parameters were consistently greater than those of Cd. These effects were of a detrimental nature and large enough in most cases to significantly impact soil productivity. It is clear that new protocols are needed for evaluating potential effects of heavy metal loading of soils.

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Rapid Diagnosis of CMT1A Duplications and HNPP Deletions by Multiplex Microsatellite PCR

  • Choi, Byung-Ok;Kim, Joonki;Lee, Kyung Lyong;Yu, Jin Seok;Hwang, Jung Hee;Chung, Ki Wha
    • Molecules and Cells
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    • 제23권1호
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    • pp.39-48
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    • 2007
  • Charcot-Marie-Tooth (CMT) disease and hereditary neuropathy with liability to pressure palsies (HNPP) are frequent forms of genetically heterogeneous peripheral neuropathies. Reciprocal unequal crossover between flanking CMT1A-REPs on chromosome 17p11.2-p12 is a major cause of CMT type 1A (CMT1A) and HNPP. The importance of a sensitive and rapid method for identifying the CMT1A duplication and HNPP deletion is being emphasized. In the present study, we established a molecular diagnostic method for the CMT1A duplication and HNPP deletion based on hexaplex PCR of 6 microsatellite markers (D17S921, D17S9B, D17S9A, D17S918, D17S4A and D17S2230). The method is highly time-, cost- and sample-saving because the six markers are amplified by a single PCR reaction and resolved with a single capillary in 3 h. Several statistical and forensic estimates indicated that most of these markers are likely to be useful for diagnosing the peripheral neuropathies. Reproducibility, as determined by concordance between independent tests, was estimated to be 100%. The likelihood that genotypes of all six markers are homozygous in randomly selected individuals was calculated to be $1.6{\times}10^{-4}$, which indicates that the statistical error rate for this diagnosis of HNPP deletion is only 0.016%.