• 한국연초학회지
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• 제13권2호
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• pp.42-47
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• 1991

Control effect of an avirulent bacterlocin-producing strain(ABPS) Y6l-1 of Pseudomonas solanacearum on bacterial wilt was 58.8 % when the bacterial suspension had poured onto the rhizosphere soil of tobacco cultivar NC82 on one day before transplanting to the field and of hilling time. Until eight weeks after inoculation, survival of the strain on rhizoplane and in stem of the plants inoculated was better than that of other four strains tested. It suggested that survival of the ABPS in and on the plants should be supported for the sufficient protection.

• Journal of Microbiology and Biotechnology
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• 제26권5호
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• pp.900-908
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• 2016

The effects of algal inoculation on chemical oxygen demand (COD) and total nitrogen (TN) removal, and indigenous bacterial dynamics were investigated in municipal wastewater. Experiments were conducted with municipal wastewater inoculated with either Chlorella vulgaris AG10032, Selenastrum gracile UTEX 325, or Scenedesmus quadricauda AG 10308. C. vulgaris and S. gracile as fast growing algae in municipal wastewater, performed high COD and TN removal in contrast to Sc. quadricauda. The indigenous bacterial dynamics revealed by 16S rRNA gene amplification showed different bacterial shifts in response to different algal inoculations. The dominant bacterial genera of either algal case were characterized as heterotrophic nitrifying bacteria. Our results suggest that selection of indigenous bacteria that symbiotically interact with algal species is important for better performance of wastewater treatment.

• The Journal of Advanced Prosthodontics
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• 제6권3호
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• pp.207-214
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• 2014

PURPOSE. This study characterized the synthesis of a modified PMMA (Polymethyl methacrylate) denture acrylic loading platinum nanoparticles (PtN) and assessed its bacterial inhibitory efficacy to produce novel antimicrobial denture base material. MATERIALS AND METHODS. Polymerized PMMA denture acrylic disc ($20mm{\times}2mm$) specimens containing 0 (control), 10, 50, 100 and 200 mg/L of PtN were fabricated respectively. The obtained platinum-PMMA nanocomposite (PtNC) was characterized by TEM (transmission electron microscopy), SEM/EDX (scanning electron microscope/energy dispersive X-ray spectroscopy), thermogravimetric and atomic absorption spectrophotometer analysis. In antimicrobial assay, specimens were placed on the cell culture plate, and $100{\mu}L$ of microbial suspensions of S. mutans (Streptococcus mutans) and S. sobrinus (Streptococcus sobrinus) were inoculated then incubated at $37^{\circ}C$ for 24 hours. The bacterial attachment was tested by FACS (fluorescence-activated cell sorting) analysis after staining with fluorescent probe. RESULTS. PtN were successfully loaded and uniformly immobilized into PMMA denture acrylic with a proper thermal stability and similar surface morphology as compared to control. PtNC expressed significant bacterial anti-adherent effect rather than bactericidal effect above 50 mg/L PtN loaded when compared to pristine PMMA (P=.01) with no or extremely small amounts of Pt ion eluted. CONCLUSION. This is the first report on the synthesis and its antibacterial activity of Pt-PMMA nanocomposite. PMMA denture acrylic loading PtN could be a possible intrinsic antimicrobial denture material with proper mechanical characteristics, meeting those specified for denture bases. For clinical application, future studies including biocompatibility, color stability and warranting the long-term effect were still required.

• Restorative Dentistry and Endodontics
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• 제43권4호
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• pp.46.1-46.10
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• 2018

Objectives: This study was to evaluate the antibacterial effect of different instrumentation and irrigation techniques using confocal laser scanning microscopy (CLSM) after root canal inoculation with Enterococcus faecalis (E. faecalis). Materials and Methods: Mesiobuccal and mesiolingual canals of extracted mandibular molars were apically enlarged up to a size 25 hand K-file, then autoclaved and inoculated with E. faecalis. The samples were randomly divided into 4 main groups according to the system of instrumentation and irrigation: an XP-endo Shaper (XPS) combined with conventional irrigation (XPS/C) or an XP-endo Finisher (XPF) (XPS/XPF), and iRaCe combined with conventional irrigation (iRaCe/C) or combined with an XPF (iRaCe/XPF). A middle-third sample was taken from each group, and then the bacterial reduction was evaluated using CLSM at a depth of $50{\mu}m$ inside the dentinal tubules. The ratio of red fluorescence (dead cells) to green-and-red fluorescence (live and dead cells) represented the percentage of bacterial reduction. The data were then statistically analyzed using the Kruskal-Wallis test for comparisons across the groups and the Dunn test was used for pairwise comparisons. Results: The instrumentation and irrigation techniques had a significant effect on bacterial reduction (p < 0.05). The iRaCe/XPF group showed the strongest effect, followed by the XPS/XPF and XPS/C group, while the iRaCe/C group had the weakest effect. Conclusions: Combining iRaCe with XPF improved its bacterial reduction effect, while combining XPS with XPF did not yield a significant improvement in its ability to reduce bacteria at a depth of $50{\mu}m$ in the dentinal tubules.

• 한국식품영양과학회지
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• 제31권5호
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• pp.802-807
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• 2002

본 실험은 초산균인 Glwonncetobacter hansenii에 의해 코코넛 배지에서 생성된 막인 bacterial fiber가 흰쥐의 장 전반과 소장의 이당류 효소활성 및 체내 지질상태에 미치는 영 향을 조사하였다. 이를 위하여 흰쥐를 0.5% 콜레스테롤 식이로 사육하였으며 섬유소원으로 bacterial fiber를 식이의 2%로 첨가 하였으며, 효과를 비교할 실험군들에게는 섬유소원으로 식물성 cellulose와 pectin을 같은 수준으로 식이에 첨가하여 사육 하였다. 실험 4주간 동안 식이섭취량 및 체중 증가량은 세군간에 차이가 없었다. 소장의 길이, 무게 등은 군간에 유의적인 차이는 없었으나 소장점 막 sucrase활성이 bacterial fiber군에서 감소하였고, maltase 활성도 감소하는 경향이었다. 맹장의 무게가 bacterial fiber군에서 증가하였으나, 결장의 무게에는 영향이 없었고, 결장 내용물 및 건조분변량이 감소하였다 혈장 총 콜레스테롤 농도는 세군중에서 pectin군이 유의적으로 낮았고 HDL-콜레스테롤 함량은 반대로 pectin군에서 높았다. 혈장과 간조직의 중성지방 함량은 모두 bacterial fiber군에서 다른 군들에 비하여 유의적으로 낮았다. 간조직 콜레스테롤 함량은 pectin군에서 낮았다. 간조직의 상대적 무게는 군간에 차이가 없었고, 혈장 GOT 및 GPT 활성도 bacterial fiber군에서 다른 두 군에 비하여 차이가 없었다. 본 연구의 결과, 실험에서 사용한 bacterial fiber는 체내의 중성지방 수준을 낮추어 지질 상태를 개선 할 수 있는 가능성을 보여 주어 이에 대한 기전과 이 작용의 활용에 대한 연구가 요망된다. 본 실험에서는 콜레스테롤 및 소장의 구조와 소화효소에는 큰 영향을 주지 않았으나 사용하는 섬유소의 수준을 보다 높이거나 다른 섬유소와 복합적으로 사용하는 경우, 또 동물의 나이에 따라 다른 결과가 도출될 수도 있으리라고 사료되어 앞으로의 지속적인 연구가 필요하다.

• Journal of Microbiology and Biotechnology
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• 제27권10호
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• pp.1837-1843
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• 2017

Knowledge of avian host responses to brucellosis is critical to understanding how birds resist this infection; however, this mechanism is not well established. On the other hand, temperature has a major involvement in the physiology of living organisms, and cell death induced by heat is attributed to protein denaturation. This study demonstrates the direct bactericidal effect of a high temperature ($41^{\circ}C$) on Brucella abortus that resulted in the gradual reduction of intracellular bacteria and inhibited bacterial growth within avian macrophage HD11 in an increasing period of time. On the other hand, this study also revealed that high temperature does not affect the rate of bacterial uptake, as confirmed by the bacterial adherence assay. No significant difference was observed in the expression of target genes between infected and uninfected cells for both temperatures. This study suggests the susceptibility of B. abortus to bacterial death under a high temperature with an increased period of incubation, leading to suppression of bacterial growth.

• 약학회지
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• 제43권6호
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• pp.716-728
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• 1999

Whole oil and ketonic fraction (KF) of Leptospermum scoparium have been tested for their antimicrobial activity and combination effect with several antibiotics against various bacterial strains and fungi by using microbiological assay methods. Antibacterial activities of KF against a number of test strains were 2-3 fold stronger than those of whole oil. MICs of the KF were $65~125{\;}{\mu\textrm{g}}/ml$ against seven gram positive bacterial strains, $65~250{\;}{\mu\textrm{g}}/ml$ against 19 methicillin resistance Staphylococcus aureus strains, and $65~50{\;}{\mu\textrm{g}}/ml$ against 14 quinolone resistance strains. However, KF showed little or no activity against gram negative bacteria. MICs of the KF were $16~250{\;}{\mu\textrm{g}}/ml$ against more than 50% of the anaerobic bacterial strains tested. KF showed the higher antibacterial activity than bacitracin against 10 strains of Bacteroids thetaiotaomicron, or three strains of Bacteroides ovatus, and the more active than ciprofloxacin against one strain of Bacteroides thetaiotaomicron and three strains of Bacteroids ovatus. The MICs of KF was 63 and $250{\;}{\mu\textrm{g}}/ml$ against Aspergillus niger and Candida albicans, respectively. Antibacterial activities of KF in combination with 19 antibiotics against 14 strains and with four antifungal agents against one fungal strain were determined by paper strip diffusion method. While most of combination showed additivity, KF showed synergism with bacitracin, exfadroxil, cephradin, and meropenem for 29~57% of the strains tested. However, ofloxacin, enoxacin, sparfloxacin showed antagonism with KF for 43~71% of the strains. KF alone and in combination with bacitracin, gentamycin, neomycin, itraconazole, fluconazole, terfinafine and ketoconazole against five bacterial strains or one fungus strain synergistic effect was demonstrated against 33% of strains examined with FIC index value below 0.5 by checkerboard study. Synergistic effect of KF with gentamicin against Staphylococcus epidermidis 329 (QRS) was found by time-kill study.

• Journal of Applied Biological Chemistry
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• 제48권3호
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• pp.133-137
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• 2005

In vitro antimutagenicity of Bacillus natto islolated from Natto, Japanese traditional fermented food, was investigated using umu-test. Mutagenicity of S9-activated metabolites of Trp-P-2 and IQ for Salmonella typhimurium TA 1535/pSK1002 was remarkably inhibited by addition of bacterial cells and their cytoplasmic fraction. Desmutagenicity by cytoplasmic fraction increased with increasing concentration of the fraction. Bioantimutagenic effect of cytoplasm on Salmonella typhimurium SD-100 did not show bioantimutagenic activity against mutated bacterial cells induced by Trp-P-2. Cytoplasmic fraction exhibited 17% bioantimutagenicity due to desmutation caused by IQ.

• 미생물학회지
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• 제11권4호
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• pp.175-180
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• 1973

This study was attempted to see more clear relationships among the enterobacteria, especially between the intestinal normal flora and pathogenic bacteria. It has been known that some intestinal normal flora produce the bactrial metabolites that are harmful to other enteric bacteria. One of the metabolites is known as colicin, the protein fraction, which possesses certain degree of inhibitory effect against other bacterial growth fraction, whih possesses certain degree of inhibitory effect against other bacterial growth. As a preliminary study for a colicin purification, the antagonistic effect of E, coli to groups of Salmonella and Shigella has been studied by means of in vitro quantitative culture method. 1. E.coli showed definite inhibitory effects aganist both Salmonella and Shigella groups in the mixture of two organisms. 2. The inhibitory effects of E.coli in the E.coli-Salmonella and the E.coli-Shigella mixture occurred from 4 hours incubation following the inoculation. 3. Even the complete inhibition of pathogenic enteric bacterial growth was noticed in the E.coli-Salmonella mixture at overnight incubation. 4. Among the diluted mixtures, 1:100, 1:1,000, and 1:10,000, survival rate of pathogenic enteric bacteria in the mixtures with E.coli showed least affected at the 1:1,000 dilution. 5. It was found that the antagonistic effect aganist groups of Salmonella-shigella was depending upon the groups of the genera.

• 대한한방내과학회지
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• 제25권1호
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• pp.149-157
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• 2004

The chronic non-bacterial prostatis disease is relatively incurable, chronic and recurrent. Due to its prostatis barrier, chronic non-bacterial prostatis disease is difficult to be penetrated with Medicine. Nevertheless, we obtained the desired results using the method of iki action by Bojungiki-tang. The purpose of this study is to evaluate the effect of treatment and change of WBC numerical index using Bojungiki-tang. We investigated one chronic non-bacterial prostatis disease for about one year with NIH chronic prostatis symptom index, expressed prostatic secretion(EPS). After the treatment, symptom index score was decreased from 27 to 1. Also WBC numerical index by EPS test was decreased to zero. These results indicate that oriental medical therapy is effective in treating chronic non-bacterial prostatis disease. Therefore further study of the effect of herb-medicine is necessary.