• Environmental Analysis Health and Toxicology
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• 제5권3_4호
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• pp.29-36
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• 1990

Aflatoxins, produced by strains of Aspergillus flavus and Aspergillus parasiticus, can be found worldwide in corn, barley, peanuts, and other commodities. Among this group of toxins, aflatoxin B$_1$was realized to be one of the most potent environmental carcinogens, mutagens and teratogens. It is routinely monitored by methods such as thin layer chromatography, liquid chromatography, fluorodensitometric technique and radioimmunoassay. However, these assays are expensive, necessitate radioactive reagents, and require overnight incubation. In this study, the determination of fungal flora in several sorts cereals has been carried out in order to obtain an appropriate information of the population of fungi. The quantitative analysis of aflatoxin B$_1$has been carried out by High Performance Liquid Chromatography (HPLC) method and Enzyme Linked Immunosorbent Assay (ELISA). The results were summarized as follow: 1) From the 100 samples,313 colonies of fungi were isolated. Among the 313 colonies, 274 were possible to identify into 11 genera. The identified genera were Aspergillus Penicillium, Mucor, Rhizopus, Alternaria, Cladosorium, Fusarium, Circinella, Chrysosporium, Paecilomyces and Phoma. 2) Six of Aspergillus flavus were aflatoxin-producing strains. Aspergillus flavus isolated from sample barleys was contained the highest content (21.8 $\mu\textrm{g}$/ml) of aflatoxin B$_1$. 3) The yield of aflatoxin B$_1$-oxime compound was appromately 75%. Aflatoxin B$_1$-oxime-Human serum albumin was approved by formal consent as complete antigen. 4) Direct competitive ELISA permitted detection of 0.15 ng levels. In the quantitative microanalysis, ELISA was superior to HPLC method.

• 생태와환경
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• 제33권1호통권89호
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• pp.9-22
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• 2000

본 연구에서는 남조류의 독성물질 배출 및 분해양상을 밝히고자 대청댐 지류인 옥천천의 스컴을 채취, 실험대상으로 하였다. Light와 dark 상태로 분리${\cdot}$배양한 배지에는 조사를 하는 동안 다른 영양염류는 첨가하지 않았다. 그 결과 세포내에서 microcystins의 총량은 세포수가 감소함에 따라 감소하였으며 Microcystis aeruginosa의 현존량과 비교하였을 때 light와 dark 상태의 경우 $r^{2}$값이 각각 0.96과 0.97로 높은 상관관계를 보였고 dark 상태에서 보다 더 빠른 감소추세를 보였다. 또한 세포에서 수체로 용존되는 microcystins의 량은 세포내에 존재하는 양의 극히 일부임을 확인 할 수 있었고 세포내에 분포하는 microcystins의 농도는 종류에 따라 차이를 보여 microcystin-RR>-LR>-YR의 순으로 존재하는 것으로 나타났다. 이러한 결과는 옥정호과 제천천을 대상으로 한 수심별 조사에서도 동일한 양상을 보였다. 수체에서 검출된 microcystins의 양은 점성물질의 양과 함께 light와 dark 상태에 따라 뚜렷한 차이를 보였으며 light의 경우 $r^{2}$값이 -0.75의 역의 상관관계를 보였다. 남조류 세포 및 microcystins에 대한 light와 dark 상태에서의 서로 다른 농도 결과는 배양 상태에 따른 미생물의 분해양상의 차이와 미생물에 대한 점성물질의 영향으로 추정된다.

• Journal of Applied Biological Chemistry
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• 제64권4호
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• pp.369-374
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• 2021

느타리버섯의 갈반병은 Pseudomonas tolaasii에 의해 생성된 톨라신 및 이의 유사 펩티드 독소에 의해 발생한다. 톨라신 펩티드들은 세포막에 pore를 형성하고 버섯의 자실체 구조를 파괴한다. 적혈구가 파괴되는 용혈은 톨라신의 세포독성에 의해 일어난다. 톨라신의 용혈활성은 Zn²⁺ 및 Ni²⁺과 같은 금속 이온에 의해 저해된다. 가돌리니움 이온을 첨가하였을 때, 톨라신에 의한 용혈작용에서 1 mM 이하의 농도에서는 용혈작용이 증가하고 그 이상의 농도에서는 저해되는 이중 효과가 나타났다. 가돌리니움 이온에 의한 톨라신 활성저해 기작은 다른 양이온들에 의한 저해기작과 다른 것으로 보인다. 가돌리니움 이온은 음전하를 갖는 막지질들에 결합하여 지질막의 측압을 변화시키는 것으로 보고되어, 톨라신 이온통로의 여닫힘에 직접 작용하기 보다는 막 구조의 단단함을 증가시켜 막에 대한 톨라신 이온통로의 안정성을 감소시키는 것으로 보인다.

• Journal of Microbiology and Biotechnology
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• 제16권11호
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• pp.1784-1790
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• 2006

Bacillus anthracis is a causative agent of anthrax. Anthrax toxins are composed of a protective antigen (PA), lethal factor (LF), and edema factor (EF), in which the PA is a central mediator for the delivery of the two enzymatic moieties LF and EF. Therefore, the PA has been an attractive target in the prevention and vaccinization for anthrax toxin. Recently, it has been reported that the molecule consisting of multiple copies of PA-binding peptide, covalently linked to a flexible polymer backbone, blocked intoxification of anthrax toxin in an animal model. In the present study, we have screened novel diverse peptides that bind to PA with a high affinity (picomolar range) from an M13 peptide display library and characterized the binding regions of the peptides. Our works provide a basis to develop novel potent inhibitors or diagnostic probes with a diverse polyvalence.

• Asian-Australasian Journal of Animal Sciences
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• 제12권3호
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• pp.467-480
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• 1999

Many antinutritional and toxic factors abound in tropical seeds, which are also generally rich in nutrients and therefore more prone to attack from herbivores. Antinutritional and toxic factors are considered to defend seeds against environmental vagaries and thus help to protect them. These factors though good for the plant, cause deleterious effects or are even toxic to animals and man. The conventional seeds cultivated for oil or non-oil purposes, and general aspects of antinutritional factors are not presented here as these have already been discussed widely by many workers. Deficits in conventional protein and energy sources in the tropics have stimulated a quest for alternative feeds both for animals and humans. This article attempts to highlight two new oilseed crops, Jatropha curcas and Moringa oleifera, and in addition deals with some under-utilized seeds with potential as animal feed. Most of these seed plants are adapted to various marginal growing conditions in the tropics and can help to mitigate the prevailing deficit in protein and energy sources. Antinutritional and toxic factors in seed or seed meal, various approaches to detoxify seed meal, and future research and development priorities for their exploitation as animal feeds are presented.

• 대한의생명과학회지
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• 제20권2호
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• pp.49-55
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• 2014

RalBP1 is an ATP-dependent non-ABC transporter, responsible for the major transport function in many cells including many cancer cell lines, causing efflux of glutathione-electrophile conjugates of both endogenous metabolites and environmental toxins. RalBP1 is expressed in most human tissues, and is over-expressed in non-small cell lung cancer cell lines and in many other tumor types. Blockade of RalBP1 by various approaches has been shown to increase sensitivity to radiation and chemotherapeutic drugs, leading to cell apoptosis. In xenograft tumor models in mice, RalBP1 blockade or depletion results in complete and sustained regression across many cancer cell types including lung cancer cells. In addition to its transport function, RalBP1 has many other cellular and physiological functions, based on its domain structure which includes a unique Ral-binding domain and a RhoGAP catalytic domain, as well as docking sites for multiple signaling proteins. Additionally, RalBP1 is also important for stromal cell function in tumors, as it was recently shown to be required for efficient endothelial cell function and angiogenesis in solid tumors. In this review, we discuss the cellular and physiological functions of RalBP1 in normal and lung cancer cells.

• Fisheries and Aquatic Sciences
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• 제7권4호
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• pp.175-183
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• 2004

The dinoflagellate Alexandrium tamiyavanichii Balech, a producer of toxins causing paralytic shellfish poisoning (PSP), has recently been considered as one of main organisms responsible for toxication of shellfish in Japan. In this study, A. tamiyavanichii was subjected to a molecular phylogenetic analysis inferred from 28S rDNA D1-D2 sequences and a species-specific LSU rRNA-targeted oligonucleotide DNA probe was designed to identify A. tamiyavanichii using the whole cell-FISH (fluorescence in situ hybridization). The sequences of the 28S rDNA D1-D2 region of A. tamiyavanichii showed no difference from A. cohorticular AF1746l4 (present name A. tamiyavanichii) and formed a distinct clade from the 'tamarensis species complex'. The probe, TAMID2, reacted specifically with A. tamiyavanichii cultured cells, without any cross-reaction with other species belonging to the same genus, including A. tamarense, A. catenella, A. affine, A. fraterculus, A. insuetum and A. pseudogonyaulax. In a test of cross-reactivity with a field sample, TAMID2 reacted consistently with only A. tamiyavanichii, indicating that the present protocol involving the TAMID2 probe might be useful for detecting toxic A. tamiyavanichii in a simple and rapid manner.

• 한국산업보건학회지
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• 제22권1호
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• pp.82-90
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• 2012

Objectives: This study was performed to provide workplaces with political guidelines that apply international CMRs (Carcinogens, Mutagens, Reproductive toxins) information to Public Notice of TLVs (Threshold Limit Values). We analyzed information supply status about CMRs of international agencies and compared substances for which TLVs are set in KMoEL (Ministry of Employment and Labor in Korea). Methods: We referred to the reliable literature about classification criteria of CMRs corresponding to UN GHS (Globally Harmonized System of classification and Labeling of chemicals) and Public Notice No. 2009-68 'Standard for Classification, Labeling of Chemical Substance and Material Safety Data Sheet' in KMoEL. The classification system of CMRs in professional organizations (IARC, NTP, ACGIH, EU ECHA, KMoEL, etc.) was investigated through the internet and literature. Conclusions: 191 chemical substances among total 650 substances with TLVs are classified as carcinogens. Also, 43 substances classified as mutagens, and 44 as reproductive toxicants. These results suggest that the information of CMRs in Public Notice of TLV will be reorganized to 191 carcinogens, 43 mutagens, and 44 reproductive toxicants.

• 농업과학연구
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• 제49권2호
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• pp.259-267
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• 2022

Although pesticides are recognized as necessary substances to improve agricultural production, exposure to pesticides is known to have a direct or indirect adverse effect on the reproductive function of mammals. The present study examines the effects of mancozeb, a well-known fungicide, on the fertility capacity of spermatozoa. Boar spermatozoa exposed to varying concentrations of mancozeb (0.01 - 0.5 µM) were evaluated for motility, motion kinetic parameters, viability, acrosome integrity and the generation of intracellular reactive oxygen species (ROS) after 30 min or 2 hrs of incubation. A significant reduction in the motility of spermatozoa was observed upon exposure to mancozeb. Similarly, there was a significant reduction of the motion kinematics of sperm treated with mancozeb as compared to untreated controls (p < 0.05). The sperm viability percentage and acrosome integrity also showed dose-dependent decreases upon exposure to mancozeb. High concentrations of mancozeb (0.2 - 0.5 µM) induced higher levels of intracellular ROS production, which resulted in the loss of the sperm membrane and decreased sperm motility due to oxidative stress. Taken together, the results here indicate that direct exposure to mancozeb affects the sperm fertility capacity. Hence, careful research that examines the interaction between reproduction and environmental toxins is crucial to prevent fertility disorders in animals.

• 생태와환경
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• 제49권4호
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• pp.375-384
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• 2016

Phytoplankton community is one of the important factors for the management of aquatic environment due to generation of varying toxins by harmful algal species. This study was performed to examine the phytoplankton community structure (PCS) in the midstream of Geum River (GR) from January 2014 to December 2015. The water sampling was performed in five stations on 2014, and three stations on 2015. Subsequently, the morphological identification was performed by microscopic observation in laboratory condition. As results, total 265 species were identified and it was comprised of 40.8% of Bacillariophyceae, 9.1% of Cyanophyceae, 44.5% of Chlorophyceae, and the others (4.9%). During the investigation period, total average standing crop of phytoplankton was $12,948cells\;mL^{-1}$, and it was comprised of $7,702cells\;mL^{-1}$ of Bacillariophyceae, $2,821cells\;mL^{-1}$ of Cyanophyceae, $2,121cells\;mL^{-1}$ of Chlorophyceae, and $305cells\;mL^{-1}$ of others. To verify which tributaries of upstream area influence on PCS of midstream of GR, the phytoplankton standing crops of two stations including Mihocheon (MH) and Gapcheon (GC) were examined on 2014, and compared to result of on 2015. The results were shown that the MH station had more similar phytoplankton standing crops with midstream of GR than GC station. The relationship between environmental parameters and phytoplankton dynamics was studied at the investigated station. As results, whereas water temperature and total phosphorus were represented the positive correlation, N/P ratio was remarkably exhibited negative correlation. From the results, it is suggested that the PCS of midstream of GR was more affected by MH station than GC station, and the changes of temperature, phosphorus concentration, and N/P ratio may be important factors on the PCS formation of midstream of GR.