• Title/Summary/Keyword: growth inhibition test

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Use of Duckweed (Lemna gibba) Growth-Inhibition Test to Evaluate the Toxicity of Chromate in Korea (환경독성 평가를 위한 좀개구리밥(Lemna gibba)의 성장저해시험법에 관한 연구)

  • 김은주;이성규
    • Environmental Analysis Health and Toxicology
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    • v.16 no.4
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    • pp.205-209
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    • 2001
  • Lemna gibba was newly cultured and provided for toxicity tests. In this study, the chromate toxicity tests for Lemna gibba were performed according to the OECD Lemna growth inhibition test guideline. The test species was Lemna gibba, and the tests were repeated 5 times. To evaluate the toxicity test results, the average specific growth rate, EC50, 95% confidential limit, and variances were calculated. The test performance was analyzed by the doubling time and test statistics. The average values of EC50 data determined by logistic and linear interpolation curves were 25.9 ppm and 35.4 ppm respectively (by chromate concentration). The doubling time of all controls were below 2.5 day, so all tests passed the criteria for the test performance. This study introduced a new test method, Lemna growth inhibition test, which is provided for the hazard assessment of aquatic environment.

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In vitro Screening of UVA Phototoxicity Inhibitors using the Natural Products (In vitro 실험법에 의한 천연물 중의 UVA 광독성 억제제 검색)

  • 김현진;김봉희
    • Environmental Analysis Health and Toxicology
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    • v.17 no.3
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    • pp.253-259
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    • 2002
  • The phototoxicity inhibitory activity of 15 natural products having antiinflammatory effect was screened by three in vitro methods: yeast growth inhibition test with Candida albicans, RBC photohemolysis and MTT assay. We induced phototoxic reaction by irradiating UVA (365 nm) on chlorpromazine (CPZ) that has been widely documented as phototoxic agent in clinical and experimental studies and then observed the effects of the natural products after treating them with CPZ. In yeast growth inhibition test, X. stramonium showed the inhibitory effect on the UVA phototoxicity and E. officinalis, Yeast, P. suffruticosa showed phototoxicity inhibitory effect in that their % hemolysis compared with control were 36.14${\pm}$ 2.69, 42.82${\pm}$1.35, 36.41${\pm}$0.48 on UVA. In MTT assay, all tested natural products increased cell viability compared with the control.

Screening of Potent Biofungicide for the Growth Inhibition of Soilborne Pathogenic Fungi, Rhizoctonia solani (잔디 뿌리병 병원균인 Rhizoctonia solani의 성장을 저해하는 미생물 선발)

  • 이은열;이재화
    • Journal of Life Science
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    • v.13 no.3
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    • pp.355-358
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    • 2003
  • Various Trichoderma spp. were evaluated for the development of biofungicides to control soilborne pathogen, Rhiztonia solani, Various Trichoderma spp. were initially tested for their ability to inhibit growth of R. solani by inhibition zone test. Inhibition zones of 3∼5 mm toward R. solani were detected on PDA agar plates. The parasitic activity of strains, the activities of cell-wall-degrading enzymes such as glucanases and chitinases, were also evaluated. Highest activities of glucanase and chitinase were 3.5 U/ml and 0.9 U/ml, respectively, Isolated Trichoderma spp. also exhibited good growth with currently used agrochemicals, which represents that the isolated biofungicides can be mutually used with agrochemicals.

Antimicrobial test of Antagonistic Microbes for Biological Control of Large patch of Zoysiagrass (잔디 Large patch의 생물학적 방제를 위한 길항 미생물의 선발과 항균력 검정)

  • Ma, Gi-Yoon;Lee, Geung-Joo
    • Proceedings of the Turfgrass Society of Korea Conference
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    • 2011.02a
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    • pp.35-35
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    • 2011
  • A large patch disease caused by Rhizoctonia solani AG2-2(IV) is a serious problem in turfgrass sites including golf courses and sports fields in Korea. The objectives of this study were to isolate some antagonistic microorganisms and to explain some involving mechanisms. Initially single colonies which were formed from the filtrates of various soil samples were obtained from LB culture and then co-cultured with R.solani AG2-2(IV) on PDA plate to explore some antagonistic microbes against for large patch fungus, Rhizoctonia solani AG2-2(IV). Out of total 82 antagonistic isolates which commonly had inhibition effect on Rhizoctonia solani AG2-2(IV) mycelial growth, one candidate (YPIN22) showed the most antifungal effect, which was confirmed by the longest distance from the edge of bacterial colony to the mycelial edge of the Rhizoctonia solani AG2-2(IV) in the dual culture. A succeeding investigation was to test any potential effect of the isolate on growth inhibition of 5 other turfgrass pathogens including R. solani solani AG2-2(IIIB), P. ultimum, C. caudatum, C. lunata, and F.oxysporum. Preliminary result indicated that the new isolate YPIN22 was also found to have antagonistic potential on the growth inhibition of those turfgrass pathogenic fungi, which was explained by inhibition zones ranging from 8 to 22mm. A further explanation of some characteristics of the isolate YPIN22 will be discussed in detail.

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In Vitro Inhibitory Activity of Cow Urine and Dung to Fusarium solani f. sp. cucurbitae

  • Basak, A.B.;Lee, Min-Woong;Lee, Tae-Soo
    • Mycobiology
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    • v.30 no.1
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    • pp.51-54
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    • 2002
  • This paper deals with the study on comparative efficacy and in vitro activity of cow urine and cow dung for controlling root rot disease of cucumber caused by Fusarium solani f. sp. cucurbitae Snyder & Hansen following slide germination and mycelial growth inhibition tests. Results showed that both germination of conidia and the percentage inhibition of mycelial growth decreased or suppressed and varied greatly with respect to different hour and days of incubation and kind of bio-matters. In between two bio-matters cow urine was found more effective than that of cow dung in conidial germination. No germination of conidia was recorded after one hour of incubation in any medium whereas in cow urine germination of conidia was not also observed even after 2 hours of incubation. After 7 hours of incubation out of 200 conidia of F. solani f. sp. cucurbitae, 28 in cow urine and 64 in cow dung were germinated while in control a total germinated conidia was 185. In case of percentage inhibition of conidial germination the highest percentage(100%) was recorded in cow urine after 2 hours of incubation followed by 3 hours(96.0%), 4 hours(91.0%) and 6 hours(89.4%). During the test on inhibition of mycelial growth, the highest percentage(62.8%) was recorded in cow urine potato dextrose agar(CUPDA) medium tested after 4 days of incubation, followed by 3 days(60.5%), 5 days(56.5%) and 2 days(55.0%). In this test cow dung potato dextrose agar(CDPDA) had less efficacy in suppression of the percentage inhibition of mycelial growth.

Application of the Ecotoxicological Standard Method using Population Growth Inhibition of Marine Phytoplankton (식물플랑크톤의 개체군성장저해율을 이용한 해양생태독성 시험방법에 관한 연구)

  • Lee, Sung-Min;Park, Gyung-Soo;An, Kyoung-Ho;Park, Soung-Yun;Lee, Sang-Hee
    • The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
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    • v.13 no.2
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    • pp.112-120
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    • 2008
  • A series of experiments were conducted to establish a marine ecotoxicological standard method using marine primary producers, Skeletonema costatum, Heterosigma akashiwo, Prorocentrum micans, Isochrysis galbana, Tetraselmis suecica as candidate test species. Marine diatom, S. costatum was selected as standard test species in terms of the ecological roles and international uses as test species. Test methods and test acceptability criteria are as follows; $72{\sim}96$ hr population growth inhibition $EC_{50}$ as endpoint. Static non-renewal method, and population growth rates over 0.04/hr in control as test acceptability criterium. S. costatum is widely distributed in the world ocean and used for standard species of marine toxicity test method by ISO (International Standardization Organization). Possible salinity ranges for this test method are $20{\sim}35\;psu$, and reproducibility and interlaboratory test results were consistent through the calibration tests. Sensitivity of the test method was comparable or better than other toxicity tests such as rotifer neonate mortality, bioluminescent bacterial inhibition, seaweed sporulation and sea urchin fertilization tests.

The Interaction of Volatile Chemicals and Phytohormones on Seed Germination and Seedling Growth of Lettuce (상치의 발아와 유묘생장에 미치는 휘발성 화학물질과 식물호르몬의 상호작용)

  • 윤경원;길봉섭
    • The Korean Journal of Ecology
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    • v.20 no.4
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    • pp.233-238
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    • 1997
  • To evaluate allelopathic effect of volatile chemicals and phytohormones, seed germination and seedling growth test of Lactuca sativa have performed in laboratory experiments. Among used chemicals terpienen-4-ol was the most inhibitory to seed germination of lettuce. ABA and GA inhibited seed germination at $5{\times}10^{-6}M$ concentration but promoted germination at $2.5{\times}10^{-5}M$ and $5{\times}10^{-5}M$. ABA and GA alleviated volatile chemical-induced inhibition of seed germination and seedling elongation of lettuce.

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Extracts for the Hair Growth Stimulation using In vivo and In vitro Test Models (In vivo와 In vitro 평가모델을 利用한 韓藥抽出物의 毛髮成長 및 促進에 미치는 實驗的 硏究)

  • Chiang, Hsueh-Chuan;Lee, Soo-Hyeong;Kim, Nam-Kwen;Lim, Hong-Jin;Hwang, Chung-Yeon
    • The Journal of Korean Medicine Ophthalmology and Otolaryngology and Dermatology
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    • v.15 no.2
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    • pp.53-79
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    • 2002
  • To screen the effective materials for hair loss treatment, several natural extracts were tested using in vivo and in vitro test models. Firstly, all test materials were applicated onto the back skin of C57BL/6 mouse and then hair growth promoting effect was measured using hair growth index. As a result, Prunus mume, black bean, Brassica campestris subsp. black sesame and Rubi Fructus showed potent hair growth promoting effect, ranking as 1.5-2.0 of hair growth index. However, there were no plant extracts, which have remarkable potential of growth promotion of human hair dermal papilla cells cultured in vitro. In the experiments of 5${\alpha}$-reductase type Ⅱ inhibition assay, Prunus mume, Eriobotryae Folium showed effective potential to inhibit the activity of 5${\alpha}$-reductase type Ⅱ. To investigate the possible involvement of the effect of several plant extracts on the gene expression of growth factors in human hair dermal papilla cells, RT - PCR analyses were performed. However, there were no plant extracts, which have profound effect on the gene expression of several growth factors such as IGF-I, KGF, HGF and VEGF in the dermal papilla cells. Another tests for inhibition of microbial such as P. acne were also carried out to find whether these plant extracts have anti -microbial activities. Rubi Fructus showed anti -microbial effects on Propionibacterium acnes, which is believed as a pathogen of acne. Together, these results showed several plant extracts can be used for hair growth promotion.

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Studies on the effects of medicinal plant extracts on the hair growth stimulation (數種의 韓藥材가 毛髮成長에 미치는 影響)

  • Choi, Woong;Choi, Jung-Hwa;Kim, Jong-Han
    • The Journal of Korean Medicine Ophthalmology and Otolaryngology and Dermatology
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    • v.15 no.2
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    • pp.80-103
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    • 2002
  • To screen the effective materials for hair loss treatment, several natural extracts were tested using in vivo and in vitro test models. Firstly, all test materials were applicated onto the back skin of C57BL/6 mouse and then hair growth pormoting effect were measured using hair growth index As a result, Polygonum muitifiorum Thunb and Terrninalia chebula Retz. showed potent hair growth promoting effect, ranking as 1.5-2.0 of hair growth index. However, there were no plant extracts, which have remarkable potential of growth promotion of human hair dermal papilla cells cultured in vitro. In the experiments of 5${\alpha}$-reductase type Ⅱ inhibition assay, Morus alba L., Chaenomelis Fructus, Saussureae Radix, Angelicae Gigantis Radix, Polygonum multifiorum Thunb, and Angelica dahurica (Fischer) Bentham et Hooker f. showed effective potential to inhibit the activity of 5${\alpha}$-reductase type Ⅱ. To investigate the possible involvement of effects of several plant extracts on the gene expression of growth factors in human hair dermal papilla cells, RT-PCR analyses were performed. As a consequences, Mentha haplocalyx Briq., Cimicifuga foetida L., Eclipta prostrata (L.) L., Pinus densiflora S. et. Z, and Polygonum muitifiorum Thunb revealed the regulatory roles on the expression of growth factors such as IGF-I, KGF, HGF and VEGF in the dermal papilla cells. Another test for inhibition of microbial such as P. acne and P. ovale were also carried out to find whether these plant extracts have anti-microbial activities. Morus alba L. and Chaenomelis Fructus showed anti-microbial effects on Propionibacterium acnes, which is believed as a pathogen of acne. Together, these results showed several plant extracts can be used for hair growth promotion.

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A Study of Ecotoxicity Test for Byproducts of Ozone in the Ballast Water Treatment System with Ozonation

  • Park, Sung-Jin;Ha, Shin-Young;Kim, In-Soo
    • Journal of Navigation and Port Research
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    • v.35 no.9
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    • pp.741-747
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    • 2011
  • Ecological toxicity testing of the whole-effluent from the ozone ballast water treatment system was conducted as specified in the quality assurance project plans (QAPP). The growth inhibition test with microalgae, acute aquatic toxicity test with the Rotifer reproduction, toxicity test (or population growth) with the Rotifer, survival and growth toxicity test with larval fish and sediment toxicity test with amphipod were carried out to evaluate ecological toxicity on the movile test barge.