• Korean Journal of Food Science and Technology
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• v.38 no.1
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• pp.28-34
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• 2006

Effects of various surface sterilization and washing methods on sterilization of fresh chicory surface were evaluated. Fresh-cut chicory was washed with tap water for 1 min, 100 ppm chlorinated water, and 3 ppm ozonated water using mechanical washing machine for 3 min, packed with bi-axially oriented polypropylene (OPP 0.04 mm) film, and stored for 3 weeks at 4 and $10^{\circ}C$. Tap water washing resulted in approximately 1 log CFU/g reduction of microbial load, and ozonated water and chlorinated water treatments resulted in additional 2 log CFU/g reduction.

• Journal of Surface Science and Engineering
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• v.43 no.1
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• pp.17-24
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• 2010

In this study, surface characteristics of dental implant fixture with various manufacturing process have been researched using electrochemical methods. The dental implant fixture was selected with 5 steps by cleaning, surface treatment and sterilization with same size and screw structure; the 1st step-machined surface, 2nd step-cleaned by thinner and prosol solution, 3th step-surface treated by RBM (resorbable blasting media) method, 4th step-cleaned and dried, 5th step-sterilized by gamma-ray. The electrochemical behavior of dental implant fixture has been evaluated by using potentiostat (EG&G Co, 2273A) in 0.9% NaCl solution at $36.5{\pm}1^{\circ}C$. The corrosion surface was observed using field-emission scanning electron microscopy (FE-SEM) and energy dispersive x-ray spectroscopy (EDS). The step 5 sample showed the cleaner and rougher surface than step 3 sample. The step 5 sample of implant fixture treated by RBM and gamma sterilization showed the low corrosion current density compared to others. Especially, the step 3 sample of implant fixture treated by RBM was presented the lowest value of corrosion resistance and the highest value of corrosion current density. The step 3 sample showed the low value of polarization resistance compared to other samples. In conclusion, the implant fixture treated with RBM and gamma sterilization has the higher corrosion resistance, and corrosion resistance depends on the step of manufacturing process.

• Journal of Korean Academy of Dental Administration
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• v.7 no.1
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• pp.50-55
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• 2019

The purpose of this study was to compare the number of bacteria before and after the use of surface disinfectants, demonstrate the bactericidal effect of surface disinfectants, and emphasize on the importance of surface disinfectants by recognizing the importance of infection control in dentistry. Chlorhexidine, hydrogen peroxide, ethanol, and chemical disinfectants are commonly used in dentistry. NaOCl was selected as the experimental group, and the bacterium test results obtained by comparing the table without surface sterilization as a control group showed that all disinfectants had an effective bactericidal effect (p<0.05). In the growth inhibition test comparing the experimental and control groups, all results were 100%, proving the effectiveness of surface disinfectants. The results showed that all surface disinfectants preferred and used by medical institutions were effective. Therefore, all surface disinfectants used in the experimental group were effective for surface disinfection for infection control. Dental clinicians should be aware of the necessity of disinfection of surfaces, such as table, chairs, and unit chairs, and make an active effort to ensure that both clinicians and patients are safe from infection.

• Journal of agriculture & life science
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• v.44 no.6
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• pp.147-157
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• 2010

This study was carried out to develop the normal temperature-circulatable retort sterilized imitation crab leg (RSIC) with long shelf-life by retort sterilization. We have examined the optimum retort sterilization conditions and quality characteristics of the RSIC. Central composite design for response surface methodology (RSM) was adopted for optimization of retort sterilization, and experimental central composite design consisted of 11 samples such as 4 factorial points; 4 star points; 3 central points. Sterilization temperature and $F_0-value$ for retort sterilization were chosen for independent variables, and shearing force, whiteness and sensory score about texture were selected as a dependent variable. As a results of RSM analysis, multiple response optimization for the RSIC by Minitap statistical programing was $F_0-value$ 3.3 min. at $117.5{^{\circ}C}$. Also RSM analysis indicated such as sterilization temperature during retort sterilization was the most influential factor, while $F_0-value$ little affected on quality of the RSIC.

• Journal of Korean society of Dental Hygiene
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• v.9 no.2
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• pp.73-88
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• 2009

The purpose of the study was to provide the basic for the prevention of infection control by analyzing the level of recognition and practice of dental hygiene students. It is important for dental clinic staffs to know and practice infection control measures in favor of effective infection control. Thus, this study conducted an one-month questionnaire survey (during October 2008) for dental hygiene students who ever experienced in 16-week clinical practice, and analyzed total 206 questionnaire forms as collected from them, so that it could determine potential associations between their recognition and practice of infection control and thereby suggest an efficient solution for infection control in dental hygiene. 1. It was found that our students' recognition about infection control averaged $4.49{\pm}.58$ points on the whole, and they were best aware of instrumental disinfection and sterilization among other measures, which was followed by hand washing, extirpation control, post-sterilization management, personal protective outfit and instrumental surface maintenance respectively. 2. It was found that our students' practice of infection control averaged $3.85{\pm}.57$ points on the whole, and they practiced hand washing most actively among other measures, which was followed by extirpation control, post-sterilization management, instrumental disinfection and sterilization, personal protective outfit and instrumental surface maintenance respectively. 3. It was found that our students scored higher mean points in recognition about every measure of infection control than those in practice (t=15.676, p=0.000). Particularly, it was notable that there were significant differences between their mean points in recognition and practice of some infection control measures, such as instrumental surface maintenance (t=15.361, p=0.000), personal protective outfit (t=15.245, p=0.000) and instrumental disinfection and sterilization (t=11.169, p=0.000). But there was least significant difference between mean points in recognition and practice of hand washing (t=5.460, p=0.000). 4. For potential associations between recognition and practice of infection control, it was found that higher recognition was in significantly positive associations with higher practice in every measure of infection control (r=.478, p=.000), such as extirpation control (r=.630, p=.000), instrumental disinfection and sterilization (r=.477, p=.000) and post-sterilization management (r=.433, p=.000). 5. It was found that there were differences in our students' recognition depending upon availability of infection control guideline (t=4.587, p=.011), and there were significant differences in practice depending on necessity of infection control education on a statistical basis (t=2.229, p=.027). Overall, it is found that our dental hygiene students are very likely to practice hand washing and extirpation control, because both of these measures are relatively easy to practice or are considered legally binding.

• Journal of Korean Society of Occupational and Environmental Hygiene
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• v.31 no.2
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• pp.138-146
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• 2021

Objectives: This study aims to compare and evaluate the reduction efficiency of disinfectants used in the domestic meat processing industry to reduce bioaerosol exposure of meat industry workers and to use this as basic data for establishing work environment management measures. Methods: Thirteen disinfectants sold in South Korea were selected for evaluation and the bacterial reduction effect of the disinfectants was investigated. Bacterial suspension and surface disinfection tests were conducted to compare and analyze the antibacterial strength of the disinfectants. Pork carcasses, cutting boards, benches, and conveyor belts were selected for surface sterilization tests. Results: As a result of the bacterial suspension experiment test, all disinfectants had a bacterial reduction efficiency of more than 86%. Among them, the bacterial reduction efficiency of chlorine disinfectants was 99.93% on average. In the results of the pork carcass surface sterilization test, the rate of reduction of disinfectants made of quaternary ammonium compounds (QACs) was the highest. Tests of plastic cutting boards showed that chlorine disinfectants had the best sterilization effect. Experiments on stainless steel benches showed the best bacterial reduction efficiency for chlorine dioxide and QACs disinfectants. In the conveyor belt made of urethane, QACs disinfectants showed excellent sterilization effects. Conclusions: The study evaluated the disinfection power of disinfectants against bacteria occurring in domestic meat processing plants. All disinfectants were found to be effective in bacterial suspension experiments, and chlorine disinfectants were particularly effective. In surface sterilization experiments, sterilizing agents with QACs as the main ingredient were excellent.

• Journal of Radiation Protection and Research
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• v.46 no.1
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• pp.8-13
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• 2021

Background: Salmonella enteritidis (SE) was the main cause of the pandemic of foodborne salmonellosis. The surface of eggs' shells can be contaminated with this bacterium; however, washing them with sodium hypochlorite solution not only reduces their flavor but also heavily impacts the environment. An alternative to this is surface sterilization using low-energy electron beam. It is known that irradiation with 1 kGy resulted in a significant 3.9 log reduction (reduction factor of 10,000) in detectable SE on the shell. FAO/IAEA/WHO indicates irradiation of any food commodity up to an overall average dose of 10 kGy presents no toxicological hazard. On the other hand, the Food and Drug Administration has deemed a dose of up to 3 kGy is allowable for eggs. However, the maximum dose permitted to be absorbed by an edible part (i.e., internal dose) is 0.1 Gy in Japan and 0.5 Gy in European Union. Materials and Methods: The electron beam (EB) depth dose distribution in the eggshell was calculated by the Monte Carlo method. The internal dose was also estimated by Monte Carlo simulation and experimentation. Results and Discussion: The EB depth dose distribution for the eggshells indicated that acceleration voltages between 80 and 200 kV were optimal for eggshell sterilization. It was also found that acceleration voltages between 80 and 150 kV were suitable for reducing the internal dose to ≤ 0.10 Gy. Conclusion: The optimum irradiative conditions for sterilizing only eggshells with an EB were between 80 and 150 kV.

• Journal of Korean society of Dental Hygiene
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• v.15 no.4
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• pp.713-718
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• 2015

Objectives: The purpose of the study was to investigate the bacterial morphology attached on ultrasonic scaler tips using no cleansing solution, alcohol cotton, liquid chemical disinfecting agent, and autoclave method. Methods: Scaling tip was applied to the mouth and the ultrasonic scaler tips were assigned to four groups. Group 1 was control group with no cleansing solution. Group 2 was treated with alcohol cotton. Group 3 was treated with 2% green Y-Na solution in liquid chemical disinfecting agent, and Group 4 was sterilized by autoclave method. Live bacteria were observed by phase contrast microscopy. The scanning electron microscopy(SEM) revealed the morphological characteristics of scaler surface. The type of attached bacteria were analyzed using SPSS 21.0 program. The data were analyzed by one-way analysis of variance(ANOVA) and Tukey's post-hoc test. Results: The types of sterilization methods had influences on the bacterial viability. The numbers of cocci, bacilli, spiral form bacteria, and filamentous bacteria was observed in $89.00{\pm}3.60%$, $29.67{\pm}3.51%$, $3.33{\pm}0.57%$ and $1.67{\pm}0.57%$ in control group, $31.67{\pm}3.51%$, $63.33{\pm}4.04%$, $2.00{\pm}1.00%$ and $1.67{\pm}0.57%$ in alcohol cotton group, $69.67{\pm}4.50%$, $12.33{\pm}2.51%$, 0% and 0% in liquid chemical disinfecting agent group, and 0.0%, 0.0%, 0.0% and 0.0% in autoclave method group. The clean surface of ultrasonic scaler tip was shown on SEM by autoclave method. Conclusions: The most effective sterilization method of ultrasonic scaler tip was the autoclave method. Autoclave method is the most effective sterilization method and can reduce the cross-infection in the dental clinic.

• Journal of Microbiology and Biotechnology
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• v.14 no.1
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• pp.188-192
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• 2004

The main aim of this study was to investigate the sterilization effects of microwave-induced argon plasma at atmospheric pressure on paper materials contaminated with fungi. Plasma-treated filter papers showed no evidence to an unaided eye of burning or paper discoloration due to the plasma treatment. All fungi were perfectly sterilized in less than 1 sec, regardless of strains. These results indicate that this sterilization method for paper materials is easy to use, requires significantly less time than other traditional methods and different plasma sterilization methods, and is also nontoxic.

• Journal of Ginseng Research
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• v.45 no.4
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• pp.519-526
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• 2021

Background: This study aimed to investigate the effect of cold plasma treatment on the improvement of seed germination and surface sterilization of ginseng seeds. Methods: Dehisced ginseng (Panax ginseng) seeds were exposed to dielectric barrier discharge (DBD) plasma operated in argon (Ar) or an argon/oxygen mixture (Ar/O₂), and the resulting germination and surface sterilization were compared with those of an untreated control group. Bacterial and fungal detection assays were performed for plasma-treated ginseng seeds after serial dilution of surface-washed suspensions. The microbial colonies (fungi and bacteria) were classified according to their phenotypical morphologies and identified by molecular analysis. Furthermore, the effect of cold plasma treatment on the in vitro antifungal activity and suppression of Cylindrocarpon destructans in 4-year-old ginseng root discs was investigated. Results: Seeds treated with plasma in Ar or Ar/O₂ exhibited a higher germination rate (%) compared with the untreated controls. Furthermore, the plasma treatment exhibited bactericidal and fungicidal effects on the seed surface, and the latter effect was stronger than the former. In addition, plasma treatment exhibited in vitro antifungal activity against C. destructans and reduced the disease severity (%) of root rot in 4-year-old ginseng root discs. The results demonstrate the stimulatory effect of plasma treatment on seed germination, surface sterilization, and root rot disease suppression in ginseng. Conclusion: The results of this study indicate that the cold plasma treatment can suppress the microbial community on the seed surface root rot in ginseng.