• The Journal of Internal Korean Medicine
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• v.34 no.3
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• pp.278-288
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• 2013

Objectives : Methicillin-resistant Staphylococcus aureus (MRSA) has a cephalosporin and beta-lactam antibiotic-resistant strains. MRSA is one of the major pathogens causing hospital infection and the isolation ratio of MRSA has gradually increased. Consequently, increased resistance to antibiotics is causing serious problems in the world. Therefore, there is a need to develop alternative antimicrobial drugs for the treatment of infectious diseases. Methods : The antibacterial activities of Ipyo-san were evaluated against 2 strains of MRSA and 1 standard Methicillin-susceptible staphylococcus aureus (MSSA) strain by using the disc diffusion method, minimal inhibitory concentrations (MIC) assay, colorimetric assay using MTT test, checkerboard dilution test and time-kill assay performed under dark. Results : The MIC of Ipyo-san water extract against S. aureus strains ranged from 1000 to $2,000{\mu}g/ml$, so we confirmed that it had a strong antibacterial effect. Also, the combinations of Ipyo-san water extract and conventional antibiotics exhibited improved inhibition of MRSA with synergy effect. We suggest that Ipyo-san water extract against MRSA has antibacterial activity so it has potential as alternatives to antibiotic agents. For the combination test, we used Triton X-100 (TX) and DCCD for measurement of membrane permeability and inhibitor of ATPase. As a result, antimicrobial activity of Ipyo-san water extract was affected by the cell membrane. Conclusions : We suggest that the Ipyo-san water extract lead the treatment of bacterial infection to solve the resistance and remaining side-effect problems that are the major weak points of traditional antibiotics.

• Journal of Life Science
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• v.15 no.2 s.69
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• pp.311-315
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• 2005

When paraquat was added to the bacterial membrane or mitochondrial suspension, the mixture turned dark blue, but the color was disappeared by aeration. The same phenomenon was seen when electrons were supplied to the paraquat. Blue color appeared from near the cathode, and then spreaded to whole transit system. Coloration was accelerated by addition of alkali, but the color was reduced by addition of acid or oxygen. Paraquat exhibited absorption at ultraviolet region by electron transfer at the concentrations as low as 1.0 mM which did not exert difficulty in showing color reaction. Paraquat caused the increase of the optical density at 340 nm by electron transit, and an aspect of that had a strong resemblance to NADH. The acute toxic action of paraquat seemes to depend on inhibition of energy metabolism cased by paraquat action of electron donor and acceptor.

• Applied Biological Chemistry
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• v.40 no.2
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• pp.167-171
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• 1997

Methanol extracts from 25 seed samples belonging to the family Leguminosae were subjected to an in vitro screening for their growth-promoting and inhibitory activities towards Bifidobacterium adolescentis, B. longum, B. bifidum, and Lactobacillus casei, using spectrophotometric and paper disc agar diffusion methods under $O_2-free$ conditions, respectively. The responses varied with both bacterial strains and plant species. Among seed extracts, extracts from Glycine max (light-green color) and Arachis hypogaea (dark-brown) enhanced the growth of lactic acid bacteria in media with or without carbon sources, suggesting that bifidus factor(s) might be involved in the phenomenon. This growth-promoting effect was most pronounced with L. casei among lactic acid bacteria used. Additionally, all seed extracts did not adversely affect the growth of the lactic acid bacteria tested.

• The Plant Pathology Journal
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• v.30 no.3
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• pp.288-298
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• 2014

We examined the efficacy of a bacterium for biocontrol of the root-knot nematode (RKN) Meloidogyne hapla in carrot (Daucus carota subsp. sativus) and tomato (Solanum lycopersicum). Among 542 bacterial isolates from various soils and plants, the highest nematode mortality was observed for treatments with isolate C1-7, which was identified as Bacillus cereus based on cultural and morphological characteristics, the Biolog program, and 16S rRNA sequencing analyses. The population density and the nematicidal activity of B. cereus C1-7 remained high until the end of culture in brain heart infusion broth, suggesting that it may have sustainable biocontrol potential. In pot experiments, the biocontrol efficacy of B. cereus C1-7 was high, showing complete inhibition of root gall or egg mass formation by RKN in carrot and tomato plants, and subsequently reducing RKN damage and suppressing nematode population growth, respectively. Light microscopy of RKN-infected carrot root tissues treated with C1-7 showed reduced formation of gall cells and fully developed giant cells, while extensive gall cells and fully mature giant cells with prominent cell wall ingrowths formed in the untreated control plants infected with RKNs. These histopathological characteristics may be the result of residual or systemic biocontrol activity of the bacterium, which may coincide with the biocontrol efficacies of nematodes in pots. These results suggest that B. cereus C1-7 can be used as a biocontrol agent for M. hapla.

• Biomolecules & Therapeutics
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• v.20 no.1
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• pp.36-42
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• 2012

Baicalin, a main constituent of the rhizome of Scutellaria baicalensis, is metabolized to baicalein and oroxylin A in the intestine before its absorption. To understand the role of intestinal microflora in the pharmacological activities of baicalin, we investigated its anti-inflammatory effect in mice treated with and without antibiotics. Orally administered baicalin showed the anti-inflammatory effect in mice than intraperitoneally treated one, apart from intraperitoneally administered its metabolites, baicalein and oroxylin A, which potently inhibited LPS-induced inflammation. Of these metabolites, oroxylin A showed more potent anti-inflammatory effect. However, treatment with the mixture of cefadroxil, oxytetracycline and erythromycin (COE) significantly attenuated the anti-inflammatory effect of orally administered baicalin in mice. Treatment with COE also reduced intestinal bacterial fecal ${\beta}$-glucuronidase activity. The metabolic activity of human stools is significantly different between individuals, but neither between ages nor between male and female. Baicalin was metabolized to baicalein and oroxylin A, with metabolic activities of $1.427{\pm}0.818$ and $1.025{\pm}0.603$ pmol/min/mg wet weight, respectively. Baicalin and its metabolites also inhibited the expression of pro-inflammatory cytokines, TNF-${\alpha}$ and IL-$1{\beta}$, and the activation of NF-${\kappa}B$B in LPS-stimulated peritoneal macrophages. Of them, oroxylin A showed the most potent inhibition. Based on these findings, baicalin may be metabolized to baicalein and oroxylin A by intestinal microflora, which enhance its anti-inflammatory effect by inhibiting NF-${\kappa}B$ activation.

• Korean Journal of Veterinary Research
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• v.40 no.1
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• pp.56-62
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• 2000

Pasteurella multocida is kind of commensal bacteria in the upper respiratory tract of pigs. It is classified toxigenic and nontoxigenic strains based on the production of dermonecrotic toxin. Toxigenic strain is most associated with atrophic rhinitis which brings great economical loss in swine industry. However, toxigenic and nontoxigenic strains do not differ by diagnostic biochemical reaction or morphology. One of recently developed techniques, PCR detects the toxigenic P multocida. Amplification of an 846-nucleotide fragment of toxA gene was developed. The fragment amplified by PCR was detected in P multocida type D not type A. The PCR amplification was as sensitive as it could detect 1 pg of P multocida DNA. We compared the result of the PCR with the enzyme linked immunosorbent assay (ELISA) in a test for 40 swine nasal swabs. All of these isolates were toxin negative based on the ELISA while 2 isolates were detected in the PCR technique. in addition to accuracy, as required for rapid detection from contaminated nasal swabs, toxigenic P multocida was recovered efficiently from contaminated culture without inhibition of the PCR. The results show that the PCR detection of toxigenic P multocida directly form nasal swabs are feasible.

• Korean Journal of Veterinary Research
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• v.34 no.1
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• pp.115-125
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• 1994

In this study, we try to establish the rapid and specific detection system for Salmonella species. The PhoE gene of Salmonella species was amplified with two specific primers, ST5 and ST8c, using PCR. The probe prepared from the amplified PhoE gene was sequenced and applied for Southern blot analysis. After PCR with ST5 and ST8c primers for PhoE gene, DNA bands of expected size(365bp) from 7 different Salmonella species were detected, but not from 12 enterobacteriaceae and 3 gram positive bacteria. PCR was highly sensitive to detect up to 10fg of purified DNA template and to identify Salmonella species with only 320 heat-lysed bacterial cells. The inhibition of PCR amplification from stool specimen was occurred with 50-fold dilution but disappeared over 100 fold dilution of samples. It was confirmed that the PhoE genes were amplified and cloned with over 97% nacleotide sequence homology of PCR products compared with that of S. typhfmurium LT2. The DNA probe derived from S. typhimurium TA 3,000 showed highly specific and sensitive reaction with PCR products of all tested Salmonella species. These results indicate that PCR was rapid and sensitive detection method for Salmonella species and DNA probe prepared from S. typhimurium TA 3,000 was specific to identify PCR products of different Salmonella species.

• Journal of Pharmacopuncture
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• v.20 no.1
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• pp.18-22
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• 2017

Objectives: The current investigation was carried out to determine the cytotoxic and the antimicrobial activities of methanolic extracts of Plumbago zeylanica. Methods: The stems, leaves, and whole plants were air dried and extracted with methanol by using a Soxhlet extractor for 72 hours at $55-60^{\circ}C$. The antimicrobial activities were determined from the zones of inhibition, which were measured by using the agar well diffusion method, and the cytotoxicity assays were performed using the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay method. Results: The methanolic extracts of the stem and the leaves of Plumbago zeylanica were tested against six bacterial species and nine fungal species, and both extracts showed antimicrobial activity in a dose-dependent manner. The leaf extract of Plumbago zeylanica showed maximum antimicrobial activity against both Staphylococcus aureus sub sp aureus and Fusarium oxysporum. The stem extract was found to be more antimicrobial against the Pseudomonas aeruginosa and the Penicillium expansum species. MTT assays were used to test the cytotoxicity of the whole plant extract in the HCT-116 and the K-562 cell lines, and that extract was shown to have weak cytotoxicity in both cell lines. Conclusion: In the present study, the methanolic stem extracts of Plumbago zeylanica were found to possess remarkable antibacterial activities against many human and agricultural pathogens. The extracts were also found to possess significant antifungal activities, but the antifungal activities were less than the antibacterial activities. Finally, the extracts were found to have weak cytotoxicities in the HCT-116 and the K-562 cell lines.

• KSBB Journal
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• v.20 no.5 s.94
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• pp.355-358
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• 2005

Bacteroides is the most predominant bacteria in the human large intestinal tract. Bacteroides fragilis RoidB isolated from a Korean faecal sample showed high $\alpha-fucosidase$ activity compared to other bacterial species. The optimized meidum for the production of $\alpha-fucosidase$ from 8. fragilis contained BHI 37g, hemin 10mg, cysteine 0.5g, resazurin 1mg, vitamin K1mg, and starch 5g per 1 L. The crude $\alpha-fucosidase$ obtained through DEAE-sepharose and CM- cellulose chromatography showed optimum temperature and pH at $40^{\circ}C$ and 7.0, respectively. Among several metals, $Co^{++}\;and\;Zn^{++}$ showed strong inhibition on enzyme activity.

• YAKHAK HOEJI
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• v.40 no.1
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• pp.102-111
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• 1996

LB10522 is a new parenteral broad spectrum cephalosporin with a catechol moiety at C-7 position of beta-lactam ring. This compound can utilize tonB-dependent iron transp ort system in addition to porin proteins to enter bacterial periplasmic space and access to penicillin-binding proteins (PBPs) which are the lethal targets of ${\beta}$-lactam antibiotics. The chelating activity of LB10522 to metal iron was measured by spectrophotometrically scanning the absorbance from 200 to 900nm. When $FeCl_3$ was added, optical density was increased between 450 and 800nm. LB10522 was more active against gram-negative strains in iron-depleted media than in iron-replete media. This is due to the increased expression of iron transport channels in iron-depleted condition. LB10522 showed a similar activity against E. coli DC2 (permeability mutant) and E. coli DCO (wild type strain) in both iron-depleted and iron-replete media, indicating a minimal permeaility barrier for LB10522 uptake. LB10522 had high affinities to PBP 3 and PBP 1A, 1B of E. coli. By blocking these proteins, LB10522 caused inhibition of cell division and the eventual death of cells. This result was correlated well with the morphological changes in E. coli exposed to LB10522. Although the in vitro MIC of LB10522 against P. aeruginosa 1912E mutant (tonB) was 8-times higher than that of the P. aeruginosa 1912E parent strain, LB10522 showed a similar in vivo protection efficacy against both strains in the mouse systemic infection model. This result suggested that tonB mutant, which requires a high level of iron for normal growth, might have a difficulty in surviving in their host with an iron-limited environment.