• Journal of Microbiology and Biotechnology
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• 제22권9호
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• pp.1288-1295
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• 2012

Exposure to bioaerosols causes various adverse health effects including infectious and respiratory diseases, and hypersensitivity. Controlling exposure to bioaerosols is important for disease control and prevention. In this study, we evaluated the efficacies of various functional filters coated with antimicrobial chemicals in deactivating representative microorganisms on filters or as bioaerosols. Tested functional filters were coated with different chemicals that included (i) Ginkgo and sumac, (ii) Ag-apatite and guanidine phosphate, (iii) $SiO_2$, ZnO, and $Al_2O_3$, and (iv) zeolite. To evaluate the filters, we used a model ventilation system (1) to evaluate the removal efficiency of bacteria (Escherichia coli and Legionella pneumophila), bacterial spores (Bacillus subtilis spore), and viruses (MS2 bacteriophage) on various functional filters, and (2) to characterize the removal efficiency of these bioaerosols. All experiments were performed at a constant temperature of $25^{\circ}C$ and humidity of 50%. Most bacteria (excluding B. subtilis) rapidly decreased on the functional filter. Therefore, we confirmed that functional filters have antimicrobial effects. Additionally, we evaluated the removal efficiency of various bioaerosols by these filters. We used a six-jet collision nebulizer to generate microbial aerosols and introduced it into the environmental chamber. We then measured the removal efficiency of functional filters with and without a medium-efficiency filter. Most bioaerosol concentrations did not significantly decrease by the functional filter only but decreased by a combination of functional and medium-efficiency filter. In conclusion, functional filters could facilitate biological removal of various bioaerosols, but physical removal of these by functional was minimal. Proper use of chemical-coated filter materials could reduce exposure to these agents.

• 한국입자에어로졸학회지
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• 제12권3호
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• pp.73-80
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• 2016

Bioaerosol inactivation becomes important as people recognize the significance on the health effects of bioaerosols. There are several ways to inactivate such bioaerosols such as antimicrobial filters, UV, etc. For the on-filter-inactivation, proper antimicrobial materials coating should be applied. Recently, air ions are adopted to effectively reduce germ and virus activity. Limitations arise when each method is applied separately. Coating materials can experience chemical instability over time and temperature. Ionizers can generate ozone to prepare high ion concentrations. Combinations of developed techniques to enhance the inactivation efficiency were suggested. Researches on the air sterilization are reviewed and outlook is highlighted. Proper techniques such as combinations of filter material coating and air ion generation can be used to make air quality better for human living.

• 한방안이비인후피부과학회지
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• 제17권1호
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• pp.143-153
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• 2004

Antimicrobial activities against Streptococcus mutans, Candida albicans, Escherichia coli, Staphylococcus epidermidis, Staphylococcus aureus were assayed through the hot water extracts and the ethanol extracts from Chungyulsodokeum and its composition oriental medicines. The stains were incubated on culture medium and activated. We observed the size of inhibition zone on the strains that is incubated in strilized filter paper disc with various concentration extracts of Chungyulsodokeum and its composition 1. The extracts of Chungyulsodokeum, Coptidis Rhizoma, Paeoniae Radix, Glycyrrhizae Radix, Gardeniae Fructus showed antimicrobial activities against Staphylococcus aureus. 2. The extracts of Chungyulsodokeum, Coptidis Rhizoma, Paeoniae Radix, Forsythiae Fructus Ghycyrrhizae Radix, showed antimiaobial activities against Staphylococcus epidermidis. 3. The extracts of Chungyulsodokeum, Coptidis Rhizoma, Paeoniae Radix, Glycyrrhizae Radix, showed antimicrobial activities against Streptococcus mutans. 4. The extract of Coptidis Rhizoma showed antimicrobial activities against Candida albicans. 5. None of the extracts showed antimicrobial activities against Escherichia coli. We observed antimicrobial activities of Chungyulsodokeum and its composition against Streptococcus mutans, Staphylococcus epidermidis, Staphylococcus aureus.

• Journal of Dental Anesthesia and Pain Medicine
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• 제16권1호
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• pp.17-24
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• 2016

Background: To evaluate the antimicrobial activity of lidocaine (LD) topical anesthetic spray against oral microflora. Methods: Antimicrobial effects of 10% LD spray were assessed against six bacterial cultures obtained from volunteers: Escherichia coli, Enterococcus faecalis, Staphylococcus aureus, Streptococcus salivarius, Streptococcus pyogenes, and Streptococcus sanguinis. The filter papers contained $50-{\mu}l$ LD, brain heart infusion (BHI) broth, or 0.2% chlorhexidine. Papers were placed on the cultured blood plates for 1-3 min. After the papers were removed, plates were incubated for 24 h. Bacterial growth on the contact areas was recorded as the antimicrobial score. The split mouth technique was use in for sample collection in clinical study. Filter papers soaked with either BHI broth or LD were placed on the right or left buccal mucosa for 1 min, and replaced with other papers to imprint biofilms onto the contact areas. Papers were placed on blood plates, incubated for 24 h, and antimicrobial scores were determined. Experiments were conducted for 2- and 3-min exposure times with a 1-day washout period. Results: LD exhibited bactericidal effects against E. coli, S. sanguinis, and S. salivarius within 1 min but displayed no effect against S. aureus, E. faecalis, and S. pyogenes. The antimicrobial effect of LD on oral microflora depended upon exposure time, similar to the results obtained from the clinical study (P < 0.05). LD showed 60-95% biofilm reduction on buccal mucosa. Conclusions: Antimicrobial activity of 10% LD topical anesthetic spray was increased by exposure time. The 3 min application reduced oral microflora in the buccal mucosa.

• 한국환경과학회지
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• 제15권11호
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• pp.1027-1034
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• 2006

Antimicrobial powder was made by exchanging silver ion on calcined oyster shell. On the purpose of application to water clarifier, bail-type media mixed with antimicrobial powder and $0{\sim}30%$ white kaoline were made. The sterilization effect, pore size distribution and zeta potential was tested to indicate the condition for the media of water clarifier. From these tests, it was confirmed that this media have an excellent sterilization power on $G^-\;and\;G^+$ germs. As the concentration of the exchanged silver ion increased, the surface charge density of the anions on the surface of the media also increased. The surface pore size decreased with the concentration of silver ion and 20% more white kaoline ratio. Consequently, mixing ratio of white kaoline would appear to indicate the optimun condition as media have sterilization power.

• 한국미생물·생명공학회지
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• 제22권6호
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• pp.700-706
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• 1994

Lactic acid bacteria in Kimchi fermentation were tested for inhibitory activity against Gram positive bacteria and Gram negative bacteria. The Lactobacillus brevis (KCCM 35464) was found to produce a antimicrobial substance. It showed relatively wide range of inhibition spectrum against gram positive and gram negative bacteria and maintained the inhibitory activity between pH 4.0 and pH 9.0. The antimicrobial substance was obtained in the stationary growth phase and was purified by gel chromatography. The inhibitory effect of the antimicrobial substance on sensitive bacterial strains was determined by filter paper test. The activity of antimicrobial substa- nce was stable at 75$\circ$C. On the basis of its electrophoretic pattern is SDS-PAGE, antimicrobial substance appeared as a single band of 59 KDalton.

• 한국산학기술학회논문지
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• 제19권4호
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• pp.311-316
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• 2018

최근 현대인들의 삶이 윤택해질수록 실내공기질 (Indoor Air Qulity)의 개선이 강하게 요구되고 있다. 생물학적 공기 오염원(세균, 진균, 바이러스 등)의 제거를 위해서 UV/광촉매 장치 또는 오존발생장치, 항균물질의 도포와 같은 방법을 사용하고 있다. 추가 에너지 소모 또는 높은 부식성과 독성, 낮은 항균력 등의 단점을 가지고 있으며, 이를 보완하기 위하여 항균력을 가진 구리를 이용하여 필터를 제작하였다. 항균동 필터의 항균력 검증을 위하여 2종의 곰팡이 (P. pinophilum, C. globosum) 와 1종의 균 (S. aureus) 에 대한 항균력을 측정하였고, 부유미생물 제거능력을 챔버 단계부터 건물의 공조시설까지 단계별 시험을 실시하였다. 그 결과 2종의 곰팡이에 대해서는 24시간 후 100% 항균력을 나타내었고, 1종의 균에 대해서는 18시간 후 99.9% 항균력을 나타내었다. 단계별 부유미생물 제거능력에서는 챔버와 공기청정기를 이용한 시험에서 항균헤파필터보다 높은 항균력을 나타내었다. 건물의 공조시설을 이용한 시험에서는 공간이 밀폐되지 않았고 지속적인 가동을 하지 않았지만 설치 후 약 2주 후부터 항균 효과가 나타나는 것으로 확인하였다. 항균동 필터의 항균력 검증 결과 제작 방법 및 소재의 연구가 더욱 필요하지만 항균 필터로써 충분한 항균력을 가진 것으로 판단된다.

• 한국식품영양과학회지
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• 제35권2호
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• pp.127-131
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• 2006

효소에 의한 옥수수 단백가수분해물의 천연항균제로서의 이용가능성을 조사하기 위하여 zein 단백질에 단백 가수분해 효소를 작용시켜 얻어진 가수분해물의 항균활성을 측정하고 membrane filter로 한외 여과하여 항균활성이 가장 높은 분획을 HPLC로 분취한 후 항균활성을 측정하고 MIC, 각종 세균에 대한 생육저해농도를 측정하여 다음과 같은 결과를 얻었다. Zein 단백질에 6종의 단백분해효소를 작용시켜 제조한 가수분해물 중 pepsin으로 작용시킨 것이 항균활성이 가장높았다. Membrane filter에 의하여 여과한가수분해물의 항균활성은 M.W. $10,000\~30,000$에서 가장 높았으며 $121^{\circ}C$에서 10분간 처리하여도 항균활성에 변화가 없는 열안정성이 매우 높았고 MIC는 2.5 mg/mL이었다. HPLC로 분리한 항균성 peptide의 N-말단 아미노산 조성은 leucine, glutamic acid, proline, phenylalanine, aspartic acid, argenine 순이었다. 분자량 $10,000\~30,000$의 가수분해 동결건조물을 3 mg/mL 농도로 nutrient broth 배지에 첨가하고 $37^{\circ}C$에서 배양하였을 때 크게 생육이 저해되었다.

• 한국식품저장유통학회지
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• 제13권1호
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• pp.88-94
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• 2006

단백 효소 가수분해물의 천연 항균제로서의 응용성을 검토하기 위하여 casein에 5종의 단백질 가수분해 효소를 작용시켜 얻어진 가수 분해물의 항균활성을 측정하고 활성이 가장 높은 가수분해물을 부분 정제하여 그 응용성을 검토하였다. Casein에 5종 단백질 분해효소를 작용시켜 얻은 가수분해물의 항균활성은 Aspergillus oryzae protease에 의한 것이 가장 높았다. 효소처리에 의하여 얻어진 가수분해 물을 30,000, 10,000, 3,000 membrane filter로 한외여과 하였을 때 항균활성은 3,000이하 분획물에 대부분 함유되어 있었으며 공시균주에 대한 최소저해농도는 $1.0\~1.5\;mg/mL$이었다. Aspergillus oryzae pretense로 작용시킨 casein 가수분해물은 $121^{\circ}C$에서 10분간 가열했을 때도 그 항균 활성을 유지하는 것으로 보아 열에 안정하였다. 가수분해물을 HPLC로 220 nm 280 nm에서 검출된 peak 별로 수집하여 항균활성을 측정 한 결과 retention time 12.6, 13.2 분에서 분취된 peptide가 활성이 있었다. 가수분해 동결건조물을 된장에 첨가하였을 때 미생물의 생육이 저해되었으며 실용성이 있었다.

• Journal of Microbiology and Biotechnology
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• 제18권11호
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• pp.1836-1840
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• 2008

Bacteriocins are antimicrobial peptides that are produced by bacteria and toxic to bacterial strains closely related to the producer strain. It has previously been reported that Bacillus thuringiensis strain NEB17 and Bacillus thuringiensis subsp. kurstaki BUPM4 produce the bacteriocins thuricin 17 (3,162 Da) and bacthuricin F4 (3,160.05 Da), respectively. Here, we demonstrate that these bacteriocins have functional similarities and show a similar spectrum of antimicrobial activities against indicator strains. We also studied the effects of sterilization methods on the recovery and biological activities of these bacteriocins. They were completely degraded by autoclaving and the two were similarly affected by the tested filter membranes. Polyvinylidene fluoride (PVDF), polyestersulfone (PES), and cellulose acetate (CA) are suitable for filter sterilization of these bacteriocins. The two bacteriocins were stable across a range of storage conditions. These data will facilitate their utilization in food preservation or agricultural applications.