• Journal of the Korean Applied Science and Technology
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• v.33 no.2
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• pp.278-285
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• 2016

The discovery of various activities of natural plants has increased interest in halophytes. Suaeda australis and S. maritime are perennial halophytes that belong to the Chenopodiaceae family. Extracts of S. australis and S. maritime plants were investigated for concentration and time-dependent antibacterial and antioxidant activities using bacterial species and 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical scavenging activity, respectively, as well as total phenolic content. The S. australis extract ($500{\mu}g/mL$) showed activity against all the bacterial species including P. aeruginosa, P. mirabilis, A. baumannii, and VRE with 61.1, 42.3, 44.49, and 40.38%, respectively, inhibition and suppressed of these four species for 12 h. Overall, the S. australis extract showed marked antibacterial activities while, in contrast, the S. maritime extract had excellent antioxidant effects. However, the effects of the two extracts were much lower than that of quercetin. The present study identified antibacterial activities of S. australis, and it would be necessary to perform further phytochemical studies of S. australis.

• The Korean Journal of Ecology
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• v.17 no.2
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• pp.171-183
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• 1994

Soil condition, total number of bacteria, soil amylase activity and microbial biomass $(CO_2-C)$ were measured at soil of different forest types. And the difference of the allelopathic effect was determined between fresh leaf extract of Quercus acutissima and Pinus rigida to the bacteria isolated from soil of different forest types. 1. Total number of bacteria in Carpinus laxiflora forest soil was 4~7 times larger than that in pinus desiflora forest soil. 2. Soil amylase activity was positively correlated with total number of soil bacteria and soil organic matter content. The amylase activity at F layer was 4~5 times larger than that at H layer, and that at H layer was 2~4 times larger than that at A layer. 3. Seasonal changes of microbial biomass showed a peak in summer, and vertical distribution of microbial biomass decreased with increasing soil depth. The microbial biomass in Pinus densiflora forest soil was larger than that in Quercus serrata forest soil. 4. Fresh leaf extract of Pinus rigida and Quercus acutissima showed an acceleration or inhibition effect on the growth of soil bacteria, and that of !. acutissima inhibited larger number of soil bacterial strains than that of P. rigida. 4.2% and 25% of soil bacterial strains isolated from soil of P. rigida and Q. acutissima forests were inhibited by fresh leaf extract of P. rigida and Q. acutissima, respectively.

• BMB Reports
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• v.30 no.1
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• pp.60-65
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• 1997

Expression of human Cu.Zn-superoxide dismutase (SOD) with activity comparable to human erythrocyte enzyme was achieved in E. coli B21(DE3) by using the pET-17b expression vector containing a T7 promoter. Recombinant human SOD was found in the cytosol of disrupted bacterial cells and represented > 25% of the total bacterial proteins. The protein produced by the E. coli cells was purified using a combination of ammonium sulfate precipitation, Sephacryl S-100 gel filtration and DEAE-Sephacel ion exchange chromatography. The recombinant Cu,Zn-SOD and human erythrocyte enzyme were compared using dismutation activity, SDS-PAGE and immunoblotting analysis. The mass of the subunits was determined to be 15,809 by using a electrospray mass spectrometer. The copper specific chelator. diethyldithiocarbamate (DOC) reacted with the recombinant Cu,Zn-SOD. At $50{\mu}M$ and $100{\mu}M$ concentrations of DOC, the dismutation activity was not inhibited for one hour but gradually reduced after one hour. This result suggests that the reaction of DOC with the enzyme occurred in two distinct phases (phase I and phase II). During phase I of this reaction, one DOC reacted with the copper center, with retention of the dismutation activity while the second DOC displaced the copper, with a loss of activity in phase II.

• Microbiology and Biotechnology Letters
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• v.41 no.4
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• pp.469-471
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• 2013

In this study, we measured the anti-bacterial activity of radioisotope Lu-177 using a new laboratory instrument. The disk method used for the measurement of existing anti-bacterial antibiotics is drug diffusion into the medium. To measure the antimicrobial activity of a radioisotope, a new type of laboratory instrument is necessary to prevent the drug from spreading and the present invention was thus tested. In the medium, a space isolated separately for radioisotope injection was used to prevent the radioisotope from spreading and radioisotopes are actually injected by this system. We found that the antibacterial activity increased according to the radiation dose increases. It is expected that, through the present study, measuring the antibacterial activity of the other radioisotopes easily in the laboratory will be possible.

• The Plant Pathology Journal
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• v.24 no.3
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• pp.328-336
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• 2008

Out of various fungi and bacteria tested for inhibition of Tobacco mosaic virus(TMV) infection using Nicotiana tabacum cv. Xanthi-nc, a bacterial isolate JB-l, identified as Pseudomonas putida had a strong direct inhibitory activity against the TMV infection. Its systemic or indirect activity was also noted at more than a half level of the direct control efficacy. Disease severity was reduced significantly in the susceptible tobacco N. tabacum cv. NC 82 by the treatment of the bacterial culture filtrate, somewhat more by the pretreatment than by simultaneous treatment, probably by inhibiting the TMV transmission and translocation in the plants, showing negative serological, which responses in the viral detection by DAS-ELISA. TMV-inhibitory substances from P. putida JB-1 were water-soluble, stable to high temperature(even boiling), and to a wide range of pH. As proteinase K nullified their antiviral activity, the TMV inhibition activity of P. putida may be derived from proteinaceous materials. In electron microscopy, TMV particles treated with the JB-1 culture were shown to be shrunken with granule-like particles attached on them. All of these aspects suggest that P. putida JB-1 may be developed as a potential agent for the control of TMV.

• IMMUNE NETWORK
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• v.10 no.6
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• pp.230-238
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• 2010

Background: The MK1 strain, a novel bacterial isolate from soft-rotten tissue of the Neungee mushroom, produces copious amounts of exopolysaccharide (EPS) in a dextrose minimal medium. This study examined the molecular characteristics and immunomodulatory activity of MK1 EPS. Methods: The EPS in the culture supernatant was purified by cold ethanol precipitation, and characterized by SDS- PAGE/silver staining and Bio-HPLC. The immunomodulatory activities of the EPS were examined using the mouse monocytic cell line, RAW 264.7 cells. Results: The molecular weights of the purified EPS were rather heterogeneous, ranging from 10.6 to 55 kDa. The EPS was composed of glucose, rhamnose, mannose, galactose, and glucosamine at an approximate molar ratio of 1.00 : 0.8 : 0.71 : 0.29 : 0.21. EPS activated the RAW cells to produce cytokines, such as TNF-${\alpha}$ and IL-$1{\beta}$, and nitric oxide (NO). EPS also induced the expression of co-stimulatory molecules, such as B7-1, B7-2 and ICAM-1, and increased the phagocytic activity. The macrophage-activating activity of EPS was not due to endotoxin contamination because the treatment of EPS with polymyin B did not reduce the macrophage-activating activity. Conclusion: The EPS produced from the MK1 strain exerts macrophage-activating activity.

• The Journal of Korean Medicine Ophthalmology and Otolaryngology and Dermatology
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• v.17 no.3
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• pp.33-37
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• 2004

Objective: The aim of this work is to investigate the antibacterial activity of the Sohporaflavanone G isolated from Sophora flavescens (S. flavescens), as the development of microbial resistance to antibiotics make it essential to constantly look for new and active compounds effective against pathogenic bacteria. Method : Sophoraflavanone G was isolated from the dried roots of Sophora flavescens Aiton (Leguminosae) by bioassay?guided fractionation. We investigated the effect of sophoraflavanone G on oral bacterial at various concentrations after incubation of 24 h in strains in the dose?dependent manner. Results: The structure of active compound, Sophoraflavanone G having a lavandulyl group at C?8, was elucidated on the basis of spectral data especially 1H?NMR and I3C?NMR. The antimicrobial activity showed that Sophoraflavanone G exhibited antimicrobial activilies against all the bacteria tested (MICs, 0.39 - 6.25 ㎍／ml). Sophoraflavanone G showed the strong antimicrobial activity against all the facultative bacteria and microaerophilic bacteria (MICs, 0.78 - 1.56 ㎍／ml) and also Sophoraflavanone G showed the strong antimicrobial activity against obligate anaerobic bacteria (MICs, 0.39 - 6.25 ㎍／ml).

• Food Science and Biotechnology
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• v.15 no.4
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• pp.559-563
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• 2006

The growth responses of six bacterial strains exposed to materials extracted from turmeric (Curcuma longa) rhizomes were examined using impregnated paper disk agar diffusion. Methanol extracts of turmeric rhizomes exhibited strong inhibitory activity against Clostridium perfringens and weak inhibitory activity toward Escherichia coli at 5 mg/disk. However, in tests conducted with Bifidobacterium adolescentis, B. bifidum, B. longum, and Lactobacillus casei, the methanol extract showed no inhibitory response. The biologically active constituent isolated from the turmeric rhizomes extracts was characterized as ar-turmerone using various spectroscopic analyses including EI-MS and NMR. The responses varied according to the dosage, chemicals, and bacterial strain tested. At 2 and 1 mg/disk, ar-turmerone strongly inhibited the growth of C. perfringens and moderately inhibited the growth of E. coli without any adverse effects on the growth of four lactic acid-bacteria. Of the commercially available compounds originating from turmeric rhizomes, curcumin exhibited strong and moderate growth inhibition against C. perfringens at 2 and 1 mg/disk, respectively, and weak growth inhibition against E. coli at 1 mg/disk. However, little or no activity was observed for borneol, 1,8-cineole, and sabinene against all six bacteria strains tested. The observed inhibitory activity of the turmeric rhizome-derived curcumin and ar-turmerone against C. perfringens and E. coli demonstrate one of the important pharmacological activities of turmeric rhizomes.

• Korean Journal of Veterinary Research
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• v.59 no.2
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• pp.75-80
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• 2019

Enrofloxacin, a fluoroquinolone, is a broad-spectrum antibiotic widely used in veterinary medicine that inhibits the action of bacterial DNA gyrase, resulting in anti-bacterial effects. This study was performed to examine whether enrofloxacin has modulatory and anti-inflammatory activity on immune cells. A few studies have reported the anti-inflammatory effects of enrofloxacin. In this study, we used mouse spleen cells treated with lipopolysaccharide (LPS) and examined the effects of enrofloxacin. Several assays were performed in LPS-treated spleen cells after the enrofloxacin treatment. Enrofloxacin inhibited the metabolic activity and mitochondrial membrane potential of LPS-treated spleen cells significantly. On the other hand, enrofloxacin did not alter the proportion of the subsets in spleen cells, and did not induce cell death. The production of tumor necrosis factor-alpha in LPS-treated spleen cells was inhibited by enrofloxacin. Overall, enrofloxacin had modulatory activity in spleen cells treated with LPS. These data may broaden the use of enrofloxacin as an antibiotic with anti-inflammatory activity in veterinary clinics.

• Mycobiology
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• v.31 no.4
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• pp.251-254
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• 2003

To select active bacterial strains to control plant diseases, 57 bacterial strains were isolated from the rhizosphere of the plants growing in various areas such as coast, middle and top of Halla Mountain in Jeju Island. Anti-fungal effect of isolated bactrial strains was tested in vitro by incubating in potato dextrose agar with isolates of four fungal plant pathogens Rhizoctonia solani, Fusarium oxysporum, Colletotrichum gloeosporioides and C. orbiculare, respectively. Thirty-four bacterial strains inhibited the hyphal growth of the plant pathogens, from which 17 strains inhibited one of the tested fungi, 10 strains two fungi, six strains three and a strain TRL2-3 inhibited all of the tested fungi. Some bacterial strains could inhibit weakly the hyphal growth of the plant pathogens, whereas some did very strongly with apparent inhibition zone between the plant pathogens and bacterial strains indicating the unfavorable condition for hyphal growth. Although there was no apparent inhibition zone, some bacterial strains showed a strong suppression of hyphal growth of plant pathogens. Especially, the inhibition by TRL2-3 was remarkably strong in all cases of the tested plant pathogens in this study that could be a possible candidate for biological control of various plant diseases.