• Title/Summary/Keyword: Cross-Contamination

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Importance and Performance Analysis of Sanitation Management in Workers at Small and Medium Foodservice Industries Using HACCP Prerequisites (HACCP 선행요건 기준을 활용한 중·소 외식업체 종사자의 위생관리 중요도·수행도 분석)

  • Lee, Hyun-Jun;Hong, Wan-Soo
    • Journal of the Korean Society of Food Science and Nutrition
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    • v.45 no.10
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    • pp.1497-1507
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    • 2016
  • The purpose of this study was to conduct importance and performance analysis of sanitation management in workers at small and medium foodservice industries using HACCP prerequisites. Questionnaires were distributed to 500 small and medium foodservice industry workers in Seoul Gyeonggi province, and a total of 458 responses were used for analysis. Factors with relatively low comparison degree were as follows. 'Handwashing and clean uniform of employee in the workplace', 'regular checking and managing of trapped vermin and rodents', 'checking stocked raw materials', 'recording and filing the results of improved food safety factors', and 'regular cleaning and sterilizing of monitoring tools' factors must be improved along with their performance levels through sanitation education. According to the IPA results, among the 15 HACCP prerequisite factors with high importance but low performance were '2. Regular checking and managing of trapped vermin and rodents', '4. Handwashing and clean uniform of employee in the workplace', '14. Preventing food cross-contamination'. Furthermore, the small and medium foodservice industry IPA with high importance but low performance were 'Regular checking and managing of trapped vermin and rodents', 'Handwashing and clean uniform of employee in the workplace', and 'Preventing food cross-contamination' for the small foodservice industry, along with 'Vermin and rodents control' and 'Recording and filing the results of improved food safety factors' for the medium foodservice industry. Thus, there is a need for reinforced hygiene education through case studies on actual food service establishments to fulfill sanitation guidelines and set amended guides for much-needed items for small and mid-sized food service.

Quantitative Real-Time PCR of Porcine Parvovirus as a Model Virus for Cleaning Validation of Chromatography during Manufacture of Plasma Derivatives (혈장분획제제 제조공정에서 크로마토그래피 세척 검증을 위한 모델바이러스로서의 Porcine Parvovirus 정량)

  • Kil Tae Gun;Kim Won Jung;Lee Dong Hyuk;Kang Yong;Sung Hark Mo;Yoo Si Hyung;Park Sue-Nie;Kim In Seop
    • Korean Journal of Microbiology
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    • v.41 no.3
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    • pp.216-224
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    • 2005
  • Chromatography has now been used successfully to provide the requisite purity for human plasma-derived biop-harmaceuticals such as coagulation factors and immunoglobulins. Recently, increasing attention has been focused on establishing efficient cleaning procedures to prevent potential contamination by microorganisms as well as carry-over contamination from batch to batch. The purpose of present study was to develop a cleaning validation system for the assurance of virus removal and/or inactivation during chromatography process. In order to establish an assay system for the validation of virus clearance during chromatography cleaning process, a quantitative real-time PCR method for porcine parvovirus(PPV) was developed, since PPV, a model virus for human parvovirus B19, has a high resistance to a range of physico-chemical treatment. Specific primers for amplification of PPV DNA was selected, and PPV DNA was quantified by use of SYBR Green I. The sensitivity of the assay was calculated to be 1.5 $TCID_{50}/ml$. The established real-time PCR assay was successfully applied to the validation of PPV removal and cleaning during SP-Sepharose cation chromatography for thrombin purification and Q-Sepharose anion chromatography for factor VIII purification. The comparative results obtained by real-time PCR assay and infectivity titrations suggested that the real-time PCR assay could be a useful method for chromatography cleaning validation and that it could have an additive effect on the interpretation and evaluation of virus clearance during the virus removal process.

Rapid Extraction of DNA using Ion Exchange Resin for Early Detection of Mycobacterium tuberculosis by the Polymerase Chain Reaction (결핵균 PCR에서 이온교환수지를 이용한 신속한 DNA 분리)

  • Kim, Cheol-Min;Park, Seung-Kyu;Shon, Mal-Hyun;Song, Sun-Dae;Kim, Young;Jun, Eun-Sook;Son, Han-Chul;Jung, Byung-Sun
    • Tuberculosis and Respiratory Diseases
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    • v.43 no.1
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    • pp.30-37
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    • 1996
  • Background: The extraction methods of DNA from clinical samples are the major obstacle to use the PCR(polymerase Chain Reaction) in routine labortary for early detection of M. tuberculosis. We tried to improve the extraction method of DNA from sputum for establishment of the PCR in routine labortary by reducing the possibility of cross contamination and performing it easily and safely. Methods: We used the $InstaGene^{TM}$ DNA extraction kit(BioRad Co.) using Chelex 100 ion exchange resin for preparation of DNA. We compared InstaGene method in 100 cases of sputum from proteinase K method which is known as the most commonly used method for DNA purification(Experiment 1). And we compared InstaGene method in 98 cases of sputum from Microwave method developed by a company in Korea(Experiment 2). In experiment 1,245bps of IS6110 were amplified and then 188bps were amplified by nested PCR. In experiment 2,536bps in primary PCR and 276bps in nested PCR were amplified and analysed by agarose gel electrophoresis and EtBr staining. Results: When we chose AFB smear, culture, or AFB smear and culture as a standard test, PCR had low specificity and positive predictive value in both experiments. The InstaGene method has higher value in sensitivity and negative predictive value significantly than proteinase K method. The InstaGene method and the Microwave methods were similar in sensitivity, specificity, positive predictive value and negative predictive value. Conclusion: Even though both methods had lower possibility of cross contamination, shorter time requirement, simplicity, and economic advantages than Proteinase K method, the InstaGene method was a little simpler than the Microwave method. Therefore, in terms of usefulness in clinical application, the Instagene method seems to be the most useful method in DNA extraction for detection of M. tuberculosis using PCR. The reliability of this method will be clarified by further studies with enough clinical samples.

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Deterioration Diagnosis and Source Area of Rock Properties at the West Stone Pagoda, Gameunsaji Temple Site, Korea (감은사지 서탑의 풍화훼손도 진단 및 석재의 산지추정)

  • Lee Chan Hee;Lee Myeong Seong;Suh Mancheol;Choi Seok-Won;Kim Man Gap
    • Economic and Environmental Geology
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    • v.37 no.5
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    • pp.569-583
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    • 2004
  • The rock properties of the West pagoda in the Gameunsaji temple site are composed mainly of dark grey porphyritic granodiorite with medium grained equigranular texture and developed with small numerous dioritic xenoliths. These xenoliths occurred with small holes due to different weathering processes. As a weathering results, the rock properties of this pagoda occur wholly softened to physical hardness because of a complex result of petrological, meteorological and biological causes. Southeastern part of the pagoda deteriorated seriously that the surface of rock blocks showed partially exfoliations, fractures, open cavities in course of granular decomposition of minerals, sea water spray and crystallization of salt from the eastern coast. The Joint between blocks has small or large fracture cross each other, contaminated and corrupted for inserting with concrete, cement mortar, rock fragments and iron plates, and partially accelerated coloration and fractures. There are serious contamination materials of algae, fungus, lichen and bryophytes on the margin and the surface on the roof stone of the pagoda, so it'll require conservation treatment biochemically for releasing vegetation inhabiting on the surface and the discontinuous plane of the blocks because of adding the weathering activity of stones and growing weeds naturally by soil processing on the fissure zone. Consisting rock for the conservation and restoration of the pagoda would be careful choice of new rock properties and epoxy to reinforce for the deterioration surfaces. For the attenuation of secondary contamination and surface humidity, the possible conservation treatments are needed.

Prevalence and Toxin Characteristics of Microorganism on Hand Towels Using for Children in Child Care Center (보육시설 유아 사용 수건의 미생물 분포 및 독소 특성)

  • Kim, Jung-Beom;Kim, Nan-Yong;Kang, Suk-Ho;Do, Young-Sook;Eom, Mi-Na;Yoon, Mi-Hye;Lee, Jong-Bok
    • Journal of Food Hygiene and Safety
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    • v.28 no.2
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    • pp.138-145
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    • 2013
  • This study was conducted to evaluate the microbiological contamination on commonly used hand towels in the child care centers and to investigate the toxin gene and toxin production ability of food-borne pathogens. A total of 22 commonly used hand towels including 7 for before use and 15 for during use were tested. The average number of total aerobic bacteria and fungi were 6.2 log CFU/100 $cm^2$ and 4.1 log CFU/100 $cm^2$. Coliform bacteria were detected in 4 out of 7 before used towels (57.1%) and all of during used towels (100%). These results showed that the sanitary conditions of hand towels in the child care centers should be improved promptly. Among the pathogenic bacteria, Staph. aureus and B. cereus without Salmonella spp. were detected in 5 (22.7%) and 11 (50.0%) out of 22 hand towels. All of Staphy. aureus isolated in this study did not possess any toxin genes and did not produce enterotoxin. The detection rate of hblC, hblD, and hblA toxin genes in B. cereus was 72.7, 72.7, and 54.5% respectively. The possession rate of nheA, nheB, and nheC toxin genes showed 81.8, 72.7, and 54.5% respectively. The cytK and entFM toxin genes were presented at 45.5 and 90.0% in B. cereus. The HBL was detected in 8 out of 11 B. cereus isolates (72.7%) and 5 B. cereus isolates produced NHE (45.5%). Ten out of eleven B. cereus isolates (90.9%) produced one or more enterotoxin such as HBL and NHE. From the results, using a private hand towel or paper towel is required to prevent the cross-contamination between commonly used hand towel and children's hands in the child care center.

THE EFFECTS OF SURFACE CONTAMINATION BY HEMOSTATIC AGENTS ON THE SHEAR BOND STRENGTH OF COMPOMER (지혈제 오염이 콤포머의 전단결합강도에 미치는 영향)

  • Heo, Jeong-Moo;Kwak, Ju-Seog;Lee, Hwang;Lee, Su-Jong;Im, Mi-Kyung
    • Restorative Dentistry and Endodontics
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    • v.27 no.2
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    • pp.150-157
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    • 2002
  • One of the latest concepts in bonding are "total etch", in which both enamel and dentin are etched with an acid to remove the smear layers, and "wet dentin" in which the dentin is not dry but left moist before application of the bonding primer Ideally the application of a bonding agent to tooth structure should be insensitive to minor contamination from oral fluids. Clinically, contaminations such as saliva, gingival fluid, blood and handpiece lubricant are often encountered by dentists during cavity preparation. The aim of this study was to evaluate the effect of contamination by hemostatic agents on shear bond strength of compomer restorations. One hundred and ten extracted human maxillary and mandibular molar teeth were collected. The teeth were removed soft tissue remnant and debris and stored in physiologic solution until they were used. Small flat area on dentin of the buccal surface were wet ground serially with 400, 800 and 1200 abrasive papers on automatic polishing machine. The teeth were randomly divided into 11 groups. Each group was conditioned as follows : Group 1: Dentin surface was not etched and not contaminated by hemostatic agents. Group 2: Dentin surface was not etched but was contaminated by Astringedent$^{\circledR}$(Ultradent product Inc., Utah, U.S.A.) Group 3: Dentin surface was not etched but was contaminated by Bosmin$^{\circledR}$(Jeil Pharm, Korea.). Group 4: Dentin surface was not etched but was contaminated by Epri-dent$^{\circledR}$(Epr Industries, NJ, U.S.A.). Group 5: Dentin surface was etched and not contaminated by hemostatic agents. Group 6: Dentin sorface was etched and contaminated by Astringedent$^{\circledR}$. Group 7 : Dentin surface was etched and contaminated by Bosmin$^{\circledR}$. Group 8: Dentin surface was etched and contaminated by Epri-dent$^{\circledR}$. Group 9: Dentin surface was contaminated by Astringedent$^{\circledR}$. The contaminated surface was rinsed by water and dried by compressed air. Group 10: Dentin surface was contaminated by Bosmin$^{\circledR}$. The contaminated surface was rinsed by water and dried by compressed air. Group 11 : Dentin surface was contaminated by Epri-dent$^{\circledR}$. The contaminated surface was rinsed by water and dried by compressed air. After surface conditioning, F2000$^{\circledR}$ was applicated on the conditoned dentin surface The teeth were thermocycled in distilled water at 5$^{\circ}C$ and 55$^{\circ}C$ for 1,000 cycles. The samples were placed on the binder with the bonded compomer-dentin interface parallel to the knife-edge shearing rod of the Universal Testing Machine(Zwick Z020, Zwick Co., Germany) running at a cross head speed or 1.0 mm/min. Group 2 showed significant decrease in shear bond strength compared with group 1 and group 6 showed significant decrease in shear bond strength compared with group 5. There were no significant differences in shear bond strength between group 5 and group 9, 10 and 11.

Two-Year Estimates of Mating System in Seed Orchard of Pinus densiflora Revealed by cpSSR and nSSR Markers (안면도 소나무 채종원 교배양식 추정모수의 연간비교)

  • Kim, Young Mi;Hong, Yong Pyo;Park, Jae In
    • Journal of Korean Society of Forest Science
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    • v.104 no.4
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    • pp.578-587
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    • 2015
  • Nuclear SSR (nSSR) and chloroplast SSR (cpSSR) markers were analyzed to assess the parameters of mating system in seed orchard, such as outcrossing rates, the number of potential pollen contributors, paternal contribution rates, degree of pollen contamination, and biparental inbreeding ($t_m-t_s$). In 2006, 2007, seeds were collected from the seed orchard of Pinus densiflora, established in 1977 at Anmyeon island. Estimates of outcrossing rates ranged from 94.9 to 100% (mean 98.9%) in 2006 and from 91.2 to 100% (mean 97.7%) in 2007 on the basis of the analysis of cpSSR haplotypes and from 90.3 to 100% (mean 95.9%) in 2006 and from 81.6 to 100% (mean 95.3%) in 2007 on the basis of the analysis of nSSR genotypes. By cross checking of both DNA markers, mean cumulative outcrossing rates of 100% and 98.9% were estimated in each year. Mean contamination rates were estimated as 48.9% and 42.4%, respectively. On the basis of cpSSR haplotype observed in each seed, paternal contribution rates (the number of pollen contributors) were estimated as 0.458 (mean 16.2) in 2006 and 0.512 (mean 14.8) in 2007. In conclusion, considering pretty high level of outcrossing rates observed in a seed orchard, there might be little to be influenced by inbreeding depression for genetic potential of the seeds induced by selfing. Estimates of the mating system parameters obtained from the two reproductive years were not statistically different, which revealed stable genetic quality of seeds produced in different years. Observed results from this study may provide useful information for the management and establishment of the seed orchard of the progressive generation.

Risk Analysis for the Harvesting Stage of Tomato Farms to Establish the Good Agriculture Practices(GAP) (GAP 모델 확립을 위한 토마토 농장 수확단계의 위해요소 조사 및 분석)

  • Lee, Chae-Won;Lee, Chi-Yeop;Heo, Rok-Won;Kim, Kyeong-Yeol;Shim, Won-Bo;Shim, Sang-In;Chung, Duck-Hwa
    • Journal of agriculture & life science
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    • v.46 no.4
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    • pp.141-153
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    • 2012
  • Samples collected from six tomato farms(A, B, C : soil culture, D, E, F : Nutriculture) located in Gyeongsangnam-do were tested for the analyses of biological(sanitary indications, major foodborne pathogens, fungi), chemical(heavy metals, pesticides) and physical hazards. The highest levels of total bacteria(7.5 log CFU/g) and coliforms(5.0 log CFU/g) in soil culture farms were higher than those of nutriculture farms(total bacteria: 2.5 log CFU/mL, coliforms: 0.6 log CFU/mL). In crops and personal hygiene soil culture farms showed a slightly higher contamination levels. From all farms, the levels of fungi in soil farms were higher than those of nutrient solution. In case of major pathogens, Bacillus cereus and Staphylococcus aureus were detected in all sample with the exception of nutrient solution. Meantime, Escherichia coli, Listeria monocytogenes, E.coli O157 and Salmonella spp. were not detected. For airborne bacteria, soilculture farms showed less contamination than nutriculture farms. A piece of glass and can was confirmed asphysical hazards. Heavy metal(Cd, Pb, Cu, Cr, Hg, Zn, Ni and As) and pesticide residues as chemical hazards were detected, but their levels were lower than the regulation limit. These results demonstrate that potential hazards on harvesting stage of tomato fam were exposed. Therefore, proper management is needed to prevent biological hazards due to cross-contamination, while physical and chemical hazards were in appropriate levels based on GAP criteria.

Analysis of the Reduction Effect of Combined Treatment with UV-C and Organic Acid to Reduce Aspergillus ochraceus and Rhodotorula mucilaginosa Contamination (Aspergillus ochraceus와 Rhodotorula mucilaginosa 저감을 위한 자외선과 유기산 복합처리 효과 분석)

  • Eun-Seon Lee;Jong-Hui Kim;Bu-Min Kim;Mi-Hwa Oh
    • Journal of Food Hygiene and Safety
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    • v.39 no.1
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    • pp.54-60
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    • 2024
  • This study investigated the effectiveness of using pathogens and aqueous acids to reduce the Aspergillus ochraceus and Rhodotorula mucilaginosa contamination in livestock production environments. For this study, 1 mL of each bacterial suspension (107-108 spores/mL) was inoculated on a knife surface, dried at 37℃, and used under each treatment condition. First, to investigate the effect of organic acids, acetic, lactic, and citric acids were used. Subsequently, to select the appropriate concentration, they were prepared at concentrations of 0.5, 1, 2, 3, 4, and 5%, respectively. Accordingly, to further maximize the effect of organic acid treatment, we combined the treatment with ultraviolet light. The two strains showed a significant difference (P<0.05) compared to the initial strain, with a greater than 90% decrease in the concentrations of all organic acids. Consequently, acetic and lactic acids decreased by approximately 5 and 2 log colony forming unit (CFU)/cm2, respectively, when treated with ultraviolet light (360 mJ/cm2); however, citric acid decreased by less than 1 log CFU/cm2. However, when manufactured with 4% acetic acid, a severe malodor was emitted, making it difficult for workers to use it in a production environment. Accordingly, the optimal treatment conditions for organic acid and ultraviolet light for application were selected as follows: immersion in a 4% lactic acid solution for 1 minute and then, sterilization with ultraviolet light at 360 mJ/cm2. Finally, when a pork meat sample was cut with a knife that was finally washed with lactic acid and treated with ultraviolet light, the low level of inoculum transferred from the cleaned knife to the surface of the sample was not detected. In conclusion, using this established method can prevent cross-contamination of the surface of the meat during processing.

Quantitative Evaluation of Foodborne Pathogenic Bacteria in Commercial Sangshik (시판 생식에서 식중독균의 정량적 평가)

  • Kwak Hyo-Sun;Whang In-Kyun;Park Jong-Seok;Kim Mi-Gyeung;Lee Kyun-Young;Gho Young-Ho;Bae Yoon-Young;Moon Sung-Yang;Byun Ju-Sun;Kwon Ki-Sung;Woo Gun-Jo
    • Journal of Food Hygiene and Safety
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    • v.21 no.1
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    • pp.41-46
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    • 2006
  • This study was carried out to survey the prevalence of foodborne pathogens in Sangshik products and their raw materials far the purpose of ensuring safety of those products in market, and establishing microbial regulatory standard. From 2002 to 2004, a total of 191 Sangshik products were purchased from market or mail-order sales, and major foodborne pathogens; E. coli, Salmonella, Staphylococcus aureus, Bacillus cereus, Clostridium perfringens, Listeria monocytogenes, Campylobacter jejuni, Yersinia enterocolitica, E. coli O157:H7, Vibrio parahaemolyticus were tested. B. cereus, C. perfringens and E. coli were detected from 29 samples (15.2%), 21 samples (11.0%) and 1 sample (0.5%), respectively. But other tested bacteria were not detected. For the identification of contamination source, 53 Sangshik ingredients were collected from 9 different manufacture factories. The results were similar with the Sangshik products. Aerobic plate counts were ranging from $1.0X10^3cfu/g\;to\;1.5X10^8cfu/g$. B. cereus was detected from 13 samples (24.5%), and counted as less than 100 cfu/g. C. perfringens were detected from 2 samples (3.8%), and counted as less than 100 cfu/g. Other foodborne pathogens were not detected except for B. cereus and C. perfringens. From the results, it was revealed that potential of microbial hazard by Sangshik was relatively low. However, it would be suggested that hygienic management and controling be needed for the prevention of growing contaminated pathogens and cross contamination during process and sale due to improper storage and management.