• 한국세라믹학회지
• /
• 제32권10호
• /
• pp.1093-1102
• /
• 1995

Water-soluble phosphate glasses containing Ag or Cu ion were prepared through melting process. Then the powdered glass samples were dissolved in D.I. water at room temperature with changing the dissolution time. In terms with the glass composition, dissolution characteristics, bactericidal effects and cytotoxicities were investigated. Dissolved amounts increased uniformly with dissolution time, and the dissolution rate was higher for ternary glass than for binary glass and with less metal oxide amount. And the dissolution rate of the glass with Ag ion was higher than that with Cu ion, and the bactericidal effect of the glass with Ag ion was also greater. Solution with more than 25 ppm of Ag was observed to have strong cytotoxicity to L929, and solutions of lower Ag concentration or with Cu seemed to have little cytotoxicity.

• 대한가정학회지
• /
• 제37권4호
• /
• pp.29-40
• /
• 1999

Effects of the commercial laundry detergents, fabric softeners, and bleaches on bactericidal activities were studied. Bactericidal activities under various conditions during washing, rinsing, and bleaching were evaluated in terms of minimum inhibitory concentration(MIC) by a broth dilution method. The experiments were carried out using Staphylococcus aureus and Escherichia coli which were usually employed in antibacterial activity tests. The results are summarized as follows : 1. All samples of Powder detergents(10 samples), soaps(7 samples) and fabric softeners(4 samples) were inactive against the Staphylococcus aureus and Escherichia coli. 2. One sample in the liquid detergents(6 samples) showed a very low MIC for Staphylococcus aureus and Escherichia coli., and three samples showed a selective effect for two bacterial strains. 3. Bleaching agent(containing peroxide) did not have bactericidal effect for Staphylococcus aureus and Escherichia coli. but the other(containing chlorine) had the effect for every bacterial strain in standard concentration. 4. All samples showed bactericidal effect above 60$^{\circ}C$.

• KSBB Journal
• /
• 제16권2호
• /
• pp.163-169
• /
• 2001

This study was undertaken to evaluate the effects of green and taste teas on the in-vitro antimicrobial activity and vacuolating toxin titer of Helicobacter pylori. Crude aqueous extracts prepared by adding 2 g of tea leaf or powder to 100 ml of boiling distilled water, and sterilized by passing through a 0.22 $mutextrm{m}$ membrane filter. Green tea, coffee, and ginger tea showed bactericidal activity on H. pylori within 3 hours. Black tea and ssangwha tea also showed bactericidal activity on H. pylori in 24 hours. Arrowroot tea show no bactericidal effect on H. pylori after 48 hours. Two fold diluted green tea and coffee decreased(1/10,000cfu) the growth of H. pylori in 24 hours, but the two fold diluted black tea, ssangwha tea, and ginger tea showed suppression effect upon of(1/10cfu) H. pylori in 24 hours. The two-fold and 10-fold diluted green tea, coffee and two-fold diluted black tea abrogated the vacuolating toxin titer of H. pylori, but the two-fold and 10-fold diluted ginger, ssangwha, ginseng, and arrowroot tea only reduced the vacuolating toxin titer of H.pylori from 1/2 to 1/8. These result suggest that green tea and coffee have effective antibacterial or bactericidal effects on H.pylori, and that they also have a neutralization effect upon the vacuolating toxin of H.pylori.

• Archives of Pharmacal Research
• /
• 제29권4호
• /
• pp.298-301
• /
• 2006

This study was investigated the bactericidal effects of calcium oxide (CaO) on three common foodborne pathogenic bacteria: Escherichia coli, Listeria monocytogenes, and Salmonella typhimurium. Each bacteria level was determined in a CaO solution (0.01, 0.03, 0.05, 0.10, 0.15, and $0.20\%$ [w/v]) exposed for either 15 sec, 30 sec, 1 min, 2 min, 3 min, 5 min, 10 min, or 30 min. All three bacteria were not greatly affected by CaO solutions at concentrations of 0.01 and $0.03\%$, however, the decline of E. coli $(99\%;\;2.78\;log_{10}CFU/mL)$, L. monocytogens $(45\%;\;1.44\;log_{10}CFU/mL)$, and S. typhimurium $(70\%;\;2.08\;log_{10}CFU/mL)$ was greatest when they were exposed to $0.05\%$ CaO solution for 10 min. Moreover, the bactericidal action of CaO was maintained for at least 24 h of storage. The results of this study provide evidence that CaO, as a substitute for synthetic chemical substances has potential for use in the disinfection and sanitization of foods and food processing equipment.

• 한국식품과학회지
• /
• 제31권2호
• /
• pp.522-526
• /
• 1999

S. mutans에 대한 키토산의 항균효과는 그 분자량에 따라 뚜렷한 차이를 보였으며, 약 30,000의 분자량을 갖는 키토산이 가장 높은 항균활성을 보였다. 키토산 처리에 의해 세포로부터 단백질, 핵산, 2가 양이온 등이 상당량 유출되는 것이 관찰되었으며, 세포내 물질의 유출정도는 키토산의 항균효과와 밀접한 상관성을 보였다. 이러한 세포내 물질의 유출은 양이온성을 띠는 키토산의 아민기와 세포벽내의 음이온 성분과의 강한 결합에 의해 세포벽의 결합력이 약화되면서 생기는 결과로서 추측되었다. 키토산처리에 의해 S. mutans의 세포벽이 원형질로부터 분리되고 세포내 물질이 세포벽 내에서 밖으로 유출되는 현상은 투과전자현미경(TEM)에 의해 확인되었다.

• Journal of Periodontal and Implant Science
• /
• 제53권2호
• /
• pp.110-119
• /
• 2023

Purpose: This study aimed to investigate the proper wavelengths for safe levels of light-emitting diode (LED) irradiation with bactericidal and photobiomodulation effects in vitro. Methods: Cell viability tests of fibroblasts and osteoblasts after LED irradiation at 470, 525, 590, 630, and 850 nm were performed using the thiazolyl blue tetrazolium bromide assay. The bactericidal effect of 470-nm LED irradiation was analyzed with Streptococcus gordonii, Aggregatibacter actinomycetemcomitans, Fusobacterium nucleatum, Porphyromonas gingivalis, and Tannerella forsythia. Levels of nitric oxide, a proinflammatory mediator, were measured to identify the anti-inflammatory effect of LED irradiation on lipopolysaccharide-stimulated inflammation in RAW 264.7 macrophages. Results: LED irradiation at wavelengths of 470, 525, 590, 630, and 850 nm showed no cytotoxic effect on fibroblasts and osteoblasts. LED irradiation at 630 and 850 nm led to fibroblast proliferation compared to no LED irradiation. LED irradiation at 470 nm resulted in bactericidal effects on S. gordonii, A. actinomycetemcomitans, F. nucleatum, P. gingivalis, and T. forsythia. Lipopolysaccharide (LPS)-induced RAW 264.7 inflammation was reduced by irradiation with 525-nm LED before LPS treatment and irradiation with 630-nm LED after LPS treatment; however, the effects were limited. Conclusions: LED irradiation at 470 nm showed bactericidal effects, while LED irradiation at 525 and 630 nm showed preventive and treatment effects on LPS-induced RAW 264.7 inflammation. The application of LED irradiation has potential as an adjuvant in periodontal therapy, although further investigations should be performed in vivo.

• International Journal of Oral Biology
• /
• 제43권3호
• /
• pp.129-132
• /
• 2018

Enterococcus faecalis is a major causative agent of endodontic treatment failure. The purpose of this study was to investigate bactericidal effects of ethanol extract of Garcinia mangostana L. (mangosteen extract) on five strains of E. faecalis that were isolated from human oral cavities. The bactericidal effects of mangosteen extract were assessed by measurement of minimum bactericidal concentration (MBC) value. The cytotoxicity of mangosteen extract on immortalized human gingival fibroblasts, hTERT-hNOF, was determined based on cell counting method. The data revealed the MBC value of mangosteen extract against the E. faecalis strains was $4{\mu}g/ml$. Additionally, the cell viability of mangosteen extract on hTERT-hNOF was 83.7-89.1% at the 1 to $16{\mu}g/ml$. These findings indicated that mangosteen extract could be used as a root canal cleaner during management of endodontic treatment failure caused by E. faecalis.

• Mycobiology
• /
• 제46권4호
• /
• pp.448-451
• /
• 2018

Fungal perylenequinones have photodynamic activity and are promising photosensitizers for photodynamic therapy (PDT). Here, we investigated the bactericidal and antitumor activities of phleichrome from the fungal perylenequinone family in vitro. Photodynamic bactericidal activity of phleichrome was analyzed by agar-well diffusion method under dark and illuminated conditions. The photodynamic antitumor activity of phleichrome was analyzed in MCF-7, HeLa, SW480, and HepG2 human cancer cell lines using in vitro cytotoxicity assays. Photodynamic bactericidal activities against Gram-negative and Gram-positive bacteria were species-specific. Antitumor activity against all tumor cell lines increased under the illuminated condition. Depending on the results of the analyses, Phleichrome has potential for further drug development related to its antibacterial and antitumor activities.

• Advances in nano research
• /
• 제15권6호
• /
• pp.567-577
• /
• 2023

The killing of bacteria by mechanical forces on nanopatterned surfaces has been defined as a mechano-bactericidal effect. Inspired by nature, this method is a new-generation technology that does not cause toxic effects and antibiotic resistance. This study aimed to simulate the mechano-bactericidal effect of nanopatterned surfaces' geometric parameters and material properties against three implant-derived bacterial species. Here, in silico models were developed to explain the interactions between the bacterial cell and the nanopatterned surface. Numerical solutions were performed based on the finite element method. Elastic and creep deformation models of bacterial cells were created. Maximum deformation, maximum stress, maximum strain, as well as mortality of the cells were calculated. The results showed that increasing the peak sharpness and decreasing the width of the nanopatterns increased the maximum deformation, stress, and strain in the walls of the three bacterial cells. The increase in spacing between nanopatterns increased the maximum deformation, stress, and strain in E. coli and P. aeruginosa cell walls it decreased in S. aureus. The decrease in width with the increase in sharpness and spacing increased the mortality of E. coli and P. aeruginosa cells, the same values did not cause mortality in S. aureus cells. In addition, it was determined that using different materials for nanopatterns did not cause a significant change in stress, strain, and deformation. This study will accelerate and promote the production of more efficient mechano-bactericidal implant surfaces by modeling the geometric structures and material properties of nanopatterned surfaces together.

• 식물병연구
• /
• 제15권2호
• /
• pp.130-133
• /
• 2009

Nano-silver 용액의 식물병원성 세균에 대한 항균 활성 검정을 하기 위해 Clavibacter michiganensis subsp. michiganensis를 포함한 10가지 균주를 대상으로 실험을 수행 하였다. Nano-silver용액은 바이오 (주)플러스에서 제공된 WA-CV-WA13B, WA-AT-WB13R과 WA-PR-WB13R용액을 사용하였으며, 10 ppm, 25 ppm, 50 ppm, 100 ppm 농도로 nano-silver 용액을 배지에 첨가하여 nano-silver 배지를 제조한 후 실험대상 세균 균주를 72 h 배양 후 생장억제 정도를 관찰하기 위하여 세균의 colony 수를 세었다. 실험 결과, WA-CV-WA13B 용액의 경우 C-1에 대하여 10 ppm에서도 높은 생장 억제 효과를 나타냈고, P-6, X-1, 그리고 X-2에 대해서도 생장억제 효과를 나타냈고, WA-AT-WB13R용액의 경우 10 ppm의 농도에서 P-6에 대하여 살균효과가 나타났다. 10 ppm의 농도에서는 C-1, X-1, 그리고 X-2에 대해서 약간의 생장억제 효과가 관찰 되었다. WA-PR-WB13R용액의 경우 10 ppm 혹은 그이상의 농도가 P-5, P-6, 그리고 X-2 균주에 대하여 살균효과를 나타내었다. 실험에 사용된 3가지 nano-silver 용액 모두 25 ppm 이상에서 모든 실험대상 식물병원성 세균에 대하여 살균효과를 나타내었으며, 이러한 결과는 nano-silver 용액을 식물병원성 세균의 방제제로 활용할 수 있는 가능성을 보여주는 결과라고 판된다.