• 대한의생명과학회지
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• 제28권3호
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• pp.195-199
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• 2022

The use of copper antibacterial films as an effective infection prevention method is increasing owing to its ability to reduce the risk of pathogen transmission. In this study, we evaluated the bacterial contamination of the antibacterial copper membrane attached to a door handle at a university over time. Six mounting locations with high floating population were selected. In three sites, the door handles with the antibacterial film were exposed, while the remaining three were not attached with the antibacterial films. On days 7 and 14, isolated bacterial strains were inoculated in BHI broth and agar, respectively. Colony-forming units (CFU) were determined after incubation. Strain identification was performed using bacterial 16s rRNA PCR and sequencing. Results showed that the bacterial population on day 14 significantly increased from 6 × 10⁹ CFU/mL (day 7) to 2 × 10¹⁰ CFU/mL. Furthermore, strain distribution was not different between the on and off the copper antibacterial film groups. In conclusion, although copper has an antibacterial activity, microbial contamination may occur with prolonged use.

• 한국초지조사료학회지
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• 제43권3호
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• pp.148-155
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• 2023

This study was aimed to isolate bacterial inoculants producing chitinase and evaluate their application effects on corn silage. Four corn silages were collected from four beef cattle farms to serve as the sources of bacterial inoculants. All isolates were tested against Fusarium graminearum head blight fungus MHGNU F132 to confirm their antifungal effects. The enzyme activities (carboxylesterase and chitinase) were also measured to isolate the bacterial inoculant. Based on the activities of anti-head blight fungus, carboxylesterase, and chitinase, L. buchneri L11-1 and L. paracasei L9-3 were subjected to silage production. Corn forage (cv. Gwangpyeongok) was ensiled into a 10 L mini silo (5 kg) in quadruplication for 90 days. A 2 × 2 factorial design consists of F. graminearum contamination at 1.010⁴ cfu/g (UCT (no contamination) vs. CT (contamination)) and inoculant application at 2.1 × 10⁵ cfu/g (CON (no inoculant) vs. INO (inoculant)) used in this study. After 90 days of ensiling, the contents of CP, NDF, and ADF increased (p<0.05) by F. graminearum contamination, while IVDMD, acetate, and aerobic stability decreased (p<0.05). Meanwhile, aerobic stability decreased (p<0.05) by inoculant application. There were interaction effects (p<0.05) on IVNDFD, NH3-N, LAB, and yeast, which were highest in UCT-INO, UCT-CON, CT-INO, and CT-CON & INO, respectively. In conclusion, this study found that mold contamination could negatively impact silage quality, but isolated inoculants had limited effects on IVNDFD and yeast.

• 한국포장학회지
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• 제19권1호
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• pp.11-15
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• 2013

도서관 등에서의 책의 위생적 유통과 관리를 위한 방안을 찾기 위하여 보관되는 책 및 관련된 환경 오염원에서의 미생물 오염도를 측정하였고, 미생물 부하를 저감시키는 방안에 대하여 연구하였다. 일반적으로 책 내부 표면의 오염도는 매우 낮으며 부주의한 취급으로 침 등과 같은 액체에 의해서 오염되는 경우에 미생물 부하가 증가될 수 있었다. 그리고 책 내부 표면에 비해서 먼지가 축적되기 쉬운 옆끝면에서 미생물 오염부하가 높았다. 책에서의 미생물적 오염의 다양성을 고려할 때, 책의 청결도 유지를 위한 조작으로서는, 미생물 부하가 많은 먼지 등의 건조 분체 오염은 공기와류 장치를 사용하고, 습윤상태의 오염은 280 nm UV LED를 사용하는 것이 적절한 것으로 나타났다. UV LED에 의한 미생물 사멸에서는 2 cm 정도의 가까운 거리에서 약 5분 정도 이상의 조사가 효과적이었고, 공기 와류에 의한 건조 분체 오염부하을 저감시키는 조건으로는 풍속 5.5 m/s에서 30초~1분의 처리가 적절하였다.

• International Journal of Oral Biology
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• 제39권3호
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• pp.137-143
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• 2014

Dental professionals are repeatedly exposed to many microorganisms present in both blood and saliva. Thus, dental professionals are at a greater risk of acquiring and spreading infections, and the implementation of infections control guidelines is necessary. Cellular phones have become a necessary device for communicating in hospitals. Cellular phones contaminated with bacteria may serve as a fomite in the transmission of pathogens by the hands of medical personnel. Nevertheless, studies about rate and levels of bacterial contamination of cellular phones have been extremely limited with regards to dental personnel. The purpose of this study was to identify bacterial flora on the cellular phones of dentists by a molecular biological method using the 16S rRNA cloning and sequencing method. We acquired total 200 clones from dentists' cell phones and identified the bacterial species. Pseudomonas (34.6%), Lactobacillus (18.5%), Azomonas (11.5%), and Janthinobacterium (6%) were the dominant genera on dentists' cell phones. The oral bacteria identified were Anaerococcus lactolyticus, Gibbsiella dentisursi, Lactobacills leiae, Streptococcus mitis, Streptococcus oligofermentans, and Streptococcus sanguinis. Pathogenic bacteria and opportunistic pathogens such as Carnobacterium funditum, Raoultella planticola, Shigella flexneri, Lactobacillus iners, Staphylococcus aureus, and Staphylococcus epidermidis were also identified.

• 대한방사선기술학회지:방사선기술과학
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• 제44권3호
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• pp.231-237
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• 2021

The ongoing coronavirus disease 2019 (COVID-19) pandemic has highlighted the importance of hospital hygiene and infection control in hospital settings. To raise hygiene awareness among ultrasound technicians, we evaluated the hygiene status of an ultrasound room, in comparison with that of objects used in daily life. Using the swab method, the following surfaces were examined: eight surfaces in the ultrasound room including the ultrasound probes (convex, linear, sector, 3D), ultrasound track ball, ultrasound keyboard, ultrasound gel (sealed and in use) and pillow as well as four surfaces of everyday objects including subway handles, common computer keyboards, common computer mouse, and cell phones. The streak plate technique was used for inoculation into media, which was observed for the formation of bacterial colonies following incubation for 24 h. Six bacterial strains were detected from objects used in the ultrasound room, including methicillin-resistant Staphylococcus aureus. Four strains of bacteria were detected on surfaces of everyday objects. The equipment and accessories used in an ultrasound room can act as vehicles for infecting patients. Establishment of standardized hygiene protocols and periodic training of the staff are recommended to avoid cross-infection.

• 한국버섯학회지
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• 제10권1호
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• pp.44-48
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• 2012

본 연구에서는 배양된 액체종균의 세균 오염 여부를 Giemsa 용액의 단일 염색으로 짧은 시간 안에 정확하게 판정이 가능한지를 조사하였다. Giemsa 용액은 혈액 골수 림프절 말라리아 원충 리케차 세포 등을 염색하는 것으로, 염기성 색소인 methylene azul과 methylene blue, 그리고 산성색소인 eosine을 methyl alcohol-glycerine에 녹여서 제조하였다. 그리고 팽이 액체종균의 폭기 배양액 분취하여 슬라이드에 올리고 Gimesa 용액으로 염색한 후 광학 현미경으로 검사하였다. 이 결과 40~60초 동안의 세균세포를 (팽나무)버섯(류) 균사세포의 부스러기나 잔존 대두박 등과 구별할 수 있었다. 이 Gimesa 용액을 이용한 염색 및 검경방법은 빠르고 간편하며 정확하므로 액체종균을 사용하는 버섯재배 농가에서도 세균 오염을 효과적으로 동정(감지)하는데 이용할 수 있다고 생각한다.

• 한국안광학회지
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• 제18권2호
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• pp.101-106
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• 2013

목적: 본 연구는 시력교정용 안경에서 범용 적으로 활용되고 있는 세척방법에 따른 오염 균의 제균 효과를 알아보고자 하였다. 방법: 실험대상 82명의 안경으로부터 세척 전후에 대한 각각의 세균을 채취하여 제균 여부를 확인하였다. 결과: 수돗물을 이용하여 초음파세척을 실시한 결과 세균 종의 수에 대한 변화가 없었으며 70% 소독용 알코올을 이용하여 초음파세척을 실시하였을 때는 46.2%의 제균 효과가 나타났으며 일반 세제를 이용하여 솔 세척 후 70% 알코올을 이용한 초음파세척을 실시한 결과 85.7%의 제균 효과가 나타났다. 결론: 시력교정용 안경에 존재하는 기회감염성 세균들은 세제를 이용하여 솔질 세척이 더욱 효과적이었는데 이것은 렌즈와 림의 틈새 등 접합부위 등에 세균들이 세제와 솔에 의해 제거 된 것으로 차후 청결한 안경의 관리를 위하여 안경의 정기적 분해 세척이 요구됨과 동시에 안경세척관리에 대한 가이드라인이 구축되어야 할 것으로 사료된다.

• 한국동물위생학회지
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• 제33권4호
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• pp.319-326
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• 2010

Bacteroiospermia is a frequently finding in fresh raw and extended porcine semen and can results in detrimental effects on semen quality and longevity. This study aims to evaluate the type of bacterial contaminants in raw and extended porcine semen and the reducing effect of antibiotic test. To investigate bacterial contaminants, out of 387 sample (raw semen 201, extended semen 186) were collected from 6 artifical insemination centers in Gyeongsangnam-do, were inoculated onto blood agar and MacKonkey agar, respectively. Bacterial colonies were selected after culturing for 48 hours, at $37^{\circ}C$, followed by Gram staining, KOH test, oxidase test, catalase test and eventually identified using VITEK System. Total 15 genus and 24 species of bacteria were isolated from these semen samlpes. In raw semen, the most prevalent contaminants were Pseudomonas aeruginosa, Escherichia coli, Proteus mirabilis, Staphylococcus auricularis, Delftia acidovorans, Acinetobacter lowffii, S. aureus and others. And in extended porcine semen, A. lowffii, S. aureus, S. auricularis and other bacteria were identified. Most of them was G(-), which is nonpathogenic bacteria. It seems that bacterial contaminants in fresh raw and extended porcine semen originated from multiple sources at the farms/stud, and were from animal origin and non-animal origins. Whereas, the 7 virus which is known to be detected in porcine semen in 75 cases was not detected. This results showed that removal of bacterial contamination in raw and extended porcine semen is essential and farms were kept for biosecurity and individual hygienes.

• 한국동물위생학회지
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• 제20권2호
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• pp.169-175
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• 1997

This study was carried out to assess the effect of the chlorine treatment into water for processing chicken products in each stage of slaughtering, with a special viewpoint related with reducing the viable number of microorganisms by which the water and the chicken body were contaminated. The mean bacterial number on chicken samples after picking process was log5.37$\pm$0.20~5.84$\pm$0.160CFU/$\textrm{cm}^2$. When assessed by standard plate count method, it was the higher one than any other processing stage in which eviscerating, pinning, packaging, and chilling was followed in order of the mean bacterial number. The coliform bacterial numbers on carcasses after sampling from different processing stages were log2.11$\pm$0.63~2.88$\pm$0.25MPN/$\textrm{cm}^2, which show almost similar numbers in each processing stage. But, after chilling process the number was decreased slightly. The bacterial counts in the water for scalding and chilling showed log3.43 $\pm$ 0.59~5.06$\pm$0.21 and log4.30$\pm$0.21~6.62$\pm$0.33CFU/$m\ell$, respectively. In the coliform counts for the water taken out from the 2nd chilling tank, the number was log1.97$\pm$0.35~2.91$\pm$0.22MPN/$m\ell$ which showed higher than those of the 1st and the 3rd chilling tank water. The effect of chlorination in reducing the bacterial numbers was accepted at the residual chlorine concentration of 1$m\ell$/$\ell$by showing the reduction from $10^8$ to $10^4$CFU level and the numbers were decreased less than 10CFU at the concentration of 5mg/$\ell$, when assessed by viable cell counts. In conclusion, these results suggested that chlorination In chilling water with final concentration of 5mg/$\ell$was strongly recommended to reduce the bacterial numbers on final chicken products.

• 한국식품영양과학회지
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• 제31권3호
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• pp.433-437
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• 2002

본 연구는 손착유 모유와 breast-pump에 의한 기계착유모유 중의 총균수와 대장균수를 검사하고 또한 냉장 및 실온보존에 따른 모유(초유, 성숙유)와 환원조제분유의 저장성을 파악하고자 시험하였다. 시험 결과 breast-pump로 수집한 모유 중의 총균수는 2.02$\times$$10^4$CFU/mL로 손착유에 의한 총균수 1.06$\times$$10^4$ CFU/mL보다 약 2배 가량 많이 나타났으며 특히 대장균의 경우, 손착유에 의한 감염율이 12.9%인 반면 breast-pump로 수집한 모유의 감염율은 19.5%로 높게 나타났다. 또한 모유와 환원조제분유를 냉장(4$^{\circ}C$) 및 실온(2$0^{\circ}C$, 3$0^{\circ}C$)상태에서 보존하면서 총균수와 대장균수의 변화를 시험한 결과, 4$^{\circ}C$에서 대장균수의 변화는 10일 동안 뚜렷한 변화를 보이지 않았으며 총균수는 지속적으로 약간 감소하는 경향을 나타냈다. 2$0^{\circ}C$에서 총균수의 변화는 모유 성숙유와 모유 초유에서 뚜렷한 증가 추세를 보이지 않았으나 대장균의 경우 지속적인 증가 추세를 보였으며, 특히 환원조제분유에서 대장균수는 12시간 이후 급속히 증가하는 경향을 나타냈다. 3$0^{\circ}C$에서 총균수의 변화는 모유 성숙유의 경우 12시간 이후 급속히 증가하는 경향을 보였으나 모유 초유의 경우 뚜렷한 증가 추세를 보여주지 않았다. 반면에 환원조제분유는 6시간 이후 급속히 증가하는 추세를 나타냈다.