Loading [MathJax]/jax/output/CommonHTML/jax.js
  • Title/Summary/Keyword: 생장 저해

Search Result 428, Processing Time 0.025 seconds

Detection of a Quorum-Sensing Inhibitor from the Natural Products (천연물로부터 Quorum Sensing 저해제의 탐색)

  • Kim, Tae-Woo;Cha, Ji-Young;Lee, Jun-Seung;Min, Bok-Kee;Baik, Hyung-Suk
    • Journal of Life Science
    • /
    • v.18 no.2
    • /
    • pp.206-212
    • /
    • 2008
  • The quorum sensing (QS) regulatory network has been the subject of extensive studies during recent years and has also attracted a lot of attention because it both positively and negatively regulates various putative virulence factors, although initially considered to be a specialized system of Vibrio fischeri and related species. In this study, to identify the novel materials which inhibit QS system of microorganisms, extracts of eighteen natural products were tested by bioassay using N-(3-oxohexanoyl)-L-homoserine lactone and N-(3-oxooctanoyl)-L-homoserine lactone synthesized in this experiment and an Agrobacterium tumefaciens NT1 biosensor strain containing a traI::lacZ fusion. The result indicated that the extracts of cabbage, leek, and onion exhibited the QS inhibition activity. Thus, materials contained in the extracts were isolated via recycling preparative HPLC and were purified via a JAIGEL-LS255 column. The common fraction corresponding to a peak of the 83 min point of them quenched the quorum sensing of A. tumefaciens NT1 biosensor strain in ABMM containing X-gal and was designated quorum sensing inhibitor-83 min (QSI-83). The QSI-83 exhibited the heat stability and did not inhibit the growth of A. tumefaciens NTl. Furthermore, thin layer chromatography (TLC) results suggested that these novel materials may be antagonists of N-acyl homoserine lactone or may inhibit the QS autoinducer synthesis by Pseudomonas syringae pv. tabaci.

Synthesis of Abscisic Acid Analogs and Their Biological Activity on Growth of Rice Seedling (합성 ABA 유도체의 벼 유묘 생장저해 작용)

  • Lee, Sang-Kap
    • Korean Journal of Environmental Agriculture
    • /
    • v.16 no.3
    • /
    • pp.269-273
    • /
    • 1997
  • This research aims at developing a new plant growth inhibitors related to abscisic acid by means of esterification of (S)-(+)-ABA with p-hydroxy methyl cinnamate and umbelliferone, and testing its biological activity on growth of rice seedlings. The over-all yield of ABA-methyl cinnamate(AC) and ABA-umbelliferone(AC) ester compounds were 83% and 78%, respectively. The growth inhibition activity of these synthetic compounds were shown about 3 to 10 times(AC) and 10 to 30 times(AU) higher than (S)-(+)-ABA.

  • PDF

Effect of Pluronic F-68 and Oxygen Vectors on Cell Growth of Angelica gigas Nakai in Fed-batch Culture

  • Jeon, Su-Hwan;Lee, Sang-Yun;Jo, Ji-Suk;Min, Byeong-Hyeok;Kim, Dong-Il
    • 한국생물공학회:학술대회논문집
    • /
    • 2000.11a
    • /
    • pp.159-162
    • /
    • 2000
  • It has been commonly known that cell growth is inhibited by the lack of dissolved oxygen and mass transfer inhibition of nutrients at stationary phase in fed-batch culture. In this study, Pluronic F-68 and oxygen vectors were added in Angelica gigas Nakai suspension culture in order to enhance cell growth in fed-batch culture. It was observed that the addition of 6%(w/v) Pluronic F-68 promoted cell growth up to 6.1% compared to control and that the use of 4%(v/v) n-hexadecane markedly enhanced cell growth up to 11.4%.

  • PDF

형질전환 CHO-K1 세포주를 이용한 EPO의 생산에서 zinc ion이 미치는 영향

  • Lee, Gyeong-Seon;Kim, Dong-Il
    • 한국생물공학회:학술대회논문집
    • /
    • 2002.04a
    • /
    • pp.309-312
    • /
    • 2002
  • Exogenous glutamine synthetase (GS) was used efficiently as a selectable marker to identify successful transfectants for the production of erythropoietin (EPO) in Chines hamster ovary (CHO-K1) cells in the absence of glutamine. Inclusion of methionine sulphoximine (MSX), an inhibitor of glutamine synthetase, enabled further selection of clones with relatively high levels of transfected glutamine synthetase and EPO genes which were coupled together. In this study, a new cell line was established by using GS system and enhancement of EPO production by zinc ion was evaluated using the transfected CHO-K1 cell line under normal condition. It was found that EPO production from CHO-K1 cells was enhanced 40% when the optimal amount of zinc ion was added.

  • PDF

Comparison of the Sensitivity of Freshwater Algae to 6 Pesticides for Paddy Rice (담수조류의 벼재배용 농약 6종에 대한 감수성 비교)

  • Bae, Chul-Han;Park, Yeon-Ki;Kim, Yeon-Sik;Cho, Kyung-Won;Lee, Suk-Hee;Jung, Chang-Kook
    • The Korean Journal of Pesticide Science
    • /
    • v.12 no.3
    • /
    • pp.222-228
    • /
    • 2008
  • Algal Growth-inhibition tests were conducted with 6 pesticides butachlor GR (5%), butachlor EW (33%), isoprothiolane GR (12%), isoprothiolane EC (40%), diazinon GR (3%) and diazinon EC (34%) to determine their comparative toxicity to three species of freshwater green algae Selenastrum capricornutum, Scenedesmus subspicatus, Chlorella vulgris and one species diatom Nitzschia palea. The test species were exposed to the test pesticide for 72 hours and the toxicity represented EC50 value calculated by the reduction in growth rate at 72 hours. The toxicity of EC or EW formulation to green algae and diatom was higher than the toxicity of GR formulation at all test in this study. Also, the toxicity of EC formulation was higher than the toxicity technical pesticide. These results indicate that the types of pesticide formulation may affect on their toxicity on algae and the green alga, S. capricornutum and S. subspicatus were more sensitive than C. vulgris. Also, the sensitivity of the diatom, N. palea showed equal or lower than S. capricornutum, S. subspicatus but more sensitive than C. vulgris.

Quantification of Inhibitory Impact of Heavy Metals on the Growth of Escherichia coli (중금속에 의한 대장균 성장 저해의 정량적 평가)

  • Jo, Gyeong-Suk;Gu, So-Yeon;Kim, Ji-Yeong;Ryu, Hui-Uk
    • Microbiology and Biotechnology Letters
    • /
    • v.32 no.4
    • /
    • pp.341-346
    • /
    • 2004
  • The quantification of the toxicological effects of the heavy metals such as Cu, Cd, Cr, Hg, and Zn on the growth of Escherichia coli was performed, and the variations of toxicwith exposure time were evaluated in adaptation procedure. The characteristics of growth inhibition on Escherichia coli by heavy metals were different with metal species, and critical concentration of each metal, which inhibited cell growth completely, were Cu of 3.5 mM, Zn of 2.5 mM, Cd of 1.5 mM, Cr of 1.2 mM, and Hg of 0.12 mM, respectively. The tolerance of E. coli against heavy metals, based on EC50 values, increased in order of Cu > Zn > Cr > Cd > Hg. The slopes obtained from the relationship between ECso values and expose time corresponds to adaptability of test organisms to the toxicants. The adaptability of test organisms to the toxicants was much higher at higher slope values. Adaptability of E. coli on heavy metals increased in order to Zn > Cd > CU >> Cr> Hg.

Effects of herbicide butachlor on Rhodospirillum rubrum KS-301 (Rhodospirillum rubrum KS-301에 미치는 제초제 butachlor의 영향)

  • 이경미;이현순
    • Korean Journal of Microbiology
    • /
    • v.27 no.3
    • /
    • pp.285-290
    • /
    • 1989
  • The biololgical effect of the preemergence rice field herbicide, butachlor(commercial name, Machete) on purple nonsulfur photosynthetic bacterium Rhodospirillum rubrum KS-301 has been studied under cultural conditions. Bacterial growth showed a tendency to decline according to the degree of the concentration of butachlor until 103 M and slmost stopped at 102M. The growth inhibitory action at 103M of butachlor was evident (4.2-18.7% inhibition of growth rate) but had little effect in nitrogen fixation. Conversely, there was a little enhancement effect(1%) in pyruvate, dinitrogen gas growing cultures. At concentration of 103 M, instead of spiral form, rod shapes were observed through phase contrast microscope and instead of vesicular intracytoplasmic membrane, irregular tubular forms were observed through electron microscope. Alkaline pH value slightly reversed tha inhibitory action of butachlor.

  • PDF

Effect of Medium Composition on In vitro Prothallus Culture of 3 Fern Species in the Family Aspleniaceae (꼬리고사리과(Aspleniaceae) 양치식물 3종 전엽체의 기내배양에 미치는 배지구성물질의 영향)

  • Jeong Jin-A;Lee Cheol-Hee
    • Korean Journal of Plant Resources
    • /
    • v.19 no.2
    • /
    • pp.259-264
    • /
    • 2006
  • This experiment was conducted to investigate the effects of medium composition, physical condition and growth regulators on prothallus proliferation in 3 fern species belonging to Aspleniaceae (Asplenium incisum, Camptosorus sibiricus and Phyllitis scolopendrium). In all of the 3 species, the effective medium for prothallus proliferation was Murashige and Skoog's basal medium with 1% sucrose and pH 5.8. The optimum NH+4:NO3 concentration ratio of protahllus proliferation was 20:40mM (1:2 ratio) in A. incisum and P. scolopendrium and 30:30mM (1:1 ratio) in C. sibiricus. However, agar content of medium did not affect the rate of prothallus proliferation. Among the selected 6 kinds of growth regulators (NAA, IAA, 2,4-D, BAP, kinetin and lip), cytokinins generally has a promotive effect, but auxins showed an inhibitory effect on prothallus growth.

Effect of Buprofezin Concentration on the Formation and Reversion of Protoplast of Ganoderma spp. and Coriolus versicolor (Buprofezin이 Ganoderma및 Coriolus 속균(屬菌)의 원형질체(原形質體) 나출(裸出) 및 재생(再生)에 미치는 영향(影響))

  • Shin, Gwan Chull;Hwang, Ewi Ill;Hwang, Kyung Sook
    • Korean Journal of Agricultural Science
    • /
    • v.19 no.1
    • /
    • pp.33-39
    • /
    • 1992
  • Effects of buprofezin, a chitin synthesis inhibitor of insects, on mycelial growth, protoplast formation and reversion of Coriolus versicolor, Ganoderma applanatum and G. lucidum were investigated. The mycelial growth of C. versicolor, G, applanatum and G, lucidum was severely inhibited by buprofezin treatment, and the inhibition rate severely as the concentration of the buprofezin increased. Aerial mycelia and oidia formation of the mushrooms were increased by buprofezin treatment, but mycelial morphology was not changed. The rate of protoplast formation and reversion of G, applanatum was greatly increased by the treatment of the buprofezin, while that of G. lucidium was decreased. The rate of protoplast formation of C. versicolor was also increased when buprofezin was added to the medium, but the rate of protoplast reversion was not affected by the treatment, From the results obtained in this experiment, we found that the rate of protoplast. formation and reversion was increased by the treatment of the buprofezin in the mushrooms such as C, versicolor and G, applanatum, whose mycelial growth was fast on the medium, while that of G. lucidum, whose mycelial growth was relatively slow, was decreased by the treatment.

  • PDF

Isolation and characterization of Bacillus amyloliquefaciens TK3 inhibiting causative bacteria of atrophic rhinitis and fowl typhoid (돼지위축성비염과 가금티푸스 병원균을 저해하는 Bacillus amyloliquefaciens TK3의 분리 및 특성 조사)

  • Jung, Taeck-Kyung;Song, Hong-Gyu
    • Korean Journal of Microbiology
    • /
    • v.51 no.2
    • /
    • pp.177-180
    • /
    • 2015
  • For prevention of atrophic rhinitis of swine by Bordetella bronchiseptica and fowl typhoid by Salmonella gallinarum, bacterial strains showing antimicrobial activity against those pathogenic bacteria were isolated from various samples collected at animal farms. Among 372 bacterial isolates strain TK3 showed the highest antibacterial activity against both pathogens, and was identified as Bacillus amyloliquefaciens by 16S rRNA gene sequence analysis. B. amyloliquefaciens TK3 could inhibit growth of both pathogens by secretion of antibacterial compounds such as siderophore, rhamnolipid and antimicrobial peptide. Production radius of siderophore on Chrome azurol S agar plate by strain TK3 was 0.53 cm after 14 days of incubation, and concentration of siderophore in King's B medium was 1.06 mmol/ml. It also secreted 82.4 mg/L of rhamnolipid, and antimicrobial peptide that completely inhibited growth of both pathogens at concentration of 30μl/ml in LB medium.