• 생명과학회지
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• 제20권10호
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• pp.1468-1475
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• 2010

유기농법과 관행 농법토양, 청정 갯벌과 오염 갯벌토양 그리고 청정 담수와 오염 담수 토양을 이용하여 계절의 변화에 따라 $^{35}SO_4^{-2}$을 이용한 황산염 환원율, 가스크로마토그래피를 이용한 황화수소 생성량, 최적확수 시험법을 이용한 황산염 환원세균의 분포, 공정시험법을 이용한 수분, 암모니아, 총 질소, 총 유기탄소, 총 탄소, 총 무기인, 총 인, 황산염 농도의 토양 성분조사를 실시하였다. 그 결과 황산염 환원율은 황산염의 농도보다 황산염 환원세균의 군집크기와 질소와 인과 같은 토양 성분과 서로 밀접한 관련이 있는 것으로 확인되었다. 그리고 황화수소 생성량은 10월 토양에서 가장 높게 나타났으나, 담수 토양 보다는 높은 황산염 농도를 함유한 갯벌 토양에서 더 높게 나타났고, 청정 지역보다는 오염 지역 토양에서 높은 값을 나타냈다. 따라서 혐기환경의 황산염 환원율과 황화수소 생성량은 황산염 환원세균의 군집과 토양 내 여러 가지 성분 그리고 온도에 의해 영향 받는 것을 확인하였다.

• Journal of Microbiology and Biotechnology
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• 제19권11호
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• pp.1415-1420
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• 2009

The aim of the present study was to examine the prevalence of thermophilic Campylobacter spp. (Campylobacter jejuni and Campylobacter coli) in soil, poultry manure, irrigation water, and freshly harvested vegetables from vegetable farms in Malaysia. C. jejuni was detected in 30.4% and 2.7% of the soil samples, 57.1 % and 0% of the manure samples, and 18.8% and 3% of the vegetable samples from farm A and farm B, respectively, when using the MPN-PCR method. Campylobacter spp. was not found in any of the irrigation water samples tested. Therefore, the present results indicate that the aged manure used by farm A was more contaminated than the composted manure used by farm B. Mostly, the leafy and root vegetables were contaminated. C. coli was not detected in any of the samples tested in the current study. Both farms tested in this study were found to be contaminated by campylobacters, thereby posing a potential risk for raw vegetable consumption in Malaysia. The present results also provide baseline data on Campylobacter contamination at the farm level.

• Food Science and Biotechnology
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• 제16권6호
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• pp.948-953
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• 2007

The powdered cereal sunsik is a partially thermal-processed product that required safety evaluations for food-borne pathogens. Thirty-six sunsik products from Korean markets were collected and analyzed for contamination by total viable cell counts, coliforms, Escherichia coli, and the spore-forming Clostridium perfringens and Bacillus cereus. Enterobacter sakazakii, as a newly emerging pathogen, was also analyzed. Approximately 28% of sunsik were contaminated at 5 log CFU/g for total viable counts. Coliforms and E. coli were detected in 33 and 4% of the samples, respectively. The spore-forming B. cereus was found in 42% of the samples at a maximal level of 3 log CFU/g on average. About 6% the samples were contaminated with Cl. perfringens at an average level of 15 CFU/g. Forty-five % of sunsik contained E. sakazakii, at levels from 0.007 to over 1.1 cell/g by MPN method. In addition, one sunsik product for infants and children showed over 3 log CFU/g for both B. cereus and E. sakazaki. Therefore, concern should be placed on controlling for microbial hazards such as B. cereus and E. sakazakii in sunsik, particularly for the products fed to infants under 6 months of age.

• 한국어병학회지
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• 제6권2호
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• pp.205-218
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• 1993

On the development of hirame(Paratichtys olivaceus) culture, outbreak of scuticociliata infection was reported to cause severe damage in Japan. To establish effective measures for isolation and cultivation of this ciliate, we tried to culture this pathogenic ciliate using medium for bacteria and fish cell lines in vitro. Scuticociliata from the brain tissues of infected fish was aseptically inoculated to CHSE-214 cells cultured in MEM-10 without antibiotic. Scuticociliata grew well and the number of ciliate reached $10^6\;cells/ml$ at temperatures of $15^{\circ}C$ to $20^{\circ}C$ for 10d. The number of ciliate cultured in the cell lines is 10 times higher than the numbers cultured in the liquid medium alone. This ciliata could be cloned by dilution method. Scuticociliata isolated could grow well on 42 different cell lines that were established from marine fish, warm freshwater fish, and salmonids. This ciliate could be preserved in liquid nitrogen for more than 6 months. Subsequently, we observed the optimal temperature and salinity for growth, and tested the sensitivities of this organism to formaldehyde, flagyl(Metronidazole), Ekuteshin(Combination compound of sulfamonometoxin and ormethoprim), and ozonixation. Optimal temperature for growth was $25^{\circ}C$ and salinity was 1.0 to 1.5%. Washed scuticociliata was killed by formaldehyde at the concentration of 50ppm for 10min, but was not completely killed even at a high concentration of 400ppm for 20min in MEM-5. Flagyl and Ekuteshin can inhibit the growth of scuticociliata at the concentration of 1,000 and $100{\mu}g/ml$ in MEM-10, respectively. More than 99% of this scuticociliata could be killed by ozonization at a dose equivalent to $1.0mg/\ell$ oxidant for 30sec in sea water. Isolated scuticociliata showed the pathogenicity to the cultured hirame by artificial infection(I. P. injection, $10^5\;cells$/fish). The number of scuticociliata in the water could be counted by most probable number(MPN) method using tissue culture, and the minimum detectable number was $1.8\;cells/\ell$. The number in the reservoir tank for water supply to the culture tank was 110 cells/l. After cleaning by elimination of the sediments from of the reservoir tank and disinfected with formaldehyde, number of scuticociliata decreased and was counted less than $1.8\;cells/\ell$ and infection rate of cultured hirame was decreased.

• 대한영양사협회학술지
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• 제4권2호
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• pp.235-244
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• 1998

Hand washing is an important component of hygiene program for food handlers. Hands can be a source of direct or indirect contamination of foods with pathogenic microorganisms. In this study, the effectiveness of hand washing methods and the use of 70% alcohol solution against transient skin bacteria was tested in an university foodservice facility. 70% alcohol solution is sprayed for 5 seconds automatically when hands are placed in the dispenser. Samples were taken using swab technique in meat cutting area, vegetable trimming area, and vegetable cutting area: before and after washing hands according to planned methods, and after being sprayed with 70% alcohol solution after washing hands. The bacteriological analysis of total plate counts, coliform, fecal coliform of food handlers' hands was done. Statistical data analysis was completed with Mann-Whitney U test and Kruskal-Wallis model using the SPSS program. The levels of initial contamination of workers' hand were significantly different by the work areas($x^2$=9.156, p<0.01). Workers in the vegetable trimming area had more heavily soiled hands than in the other work areas. Mean of TPC counts and coliform was 8.97×$10^5$ CFU/12.4$cm^2$, 2.93×$10^2$ MPN/12.4$cm^2$ respectively, but fecal coliform was not detected. Transient bacteria were removed from hands after washing and using 70% alcohol solution but were not removed completely. Mean reduction percentage in TPC varied among work areas and ranged from 93.19% to 94.99%, and in coliforms from 97.31% to 100%. A significant difference in TPC was found between before and after hand disinfection (Z=-2.714, p<.01) and between standardized hand washing procedures and un-standardized hand washing procedures(z=-2.301, p<.01). Subjects using the hand sanitizer showed a great elimination of TPC(99.45% reduction), but this effect was valid only after following proper washing procedures. Based on the results, the most effective hand washing method was recommended as the combination of the standardized hand washing procedure with warm-water and use of the 70% alcohol solution. The results can be used to develop hand hygiene programs and training strategies for enhancing hand hygiene practices for food handlers in foodservice operations.

• 한국토양비료학회지
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• 제19권2호
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• pp.157-165
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• 1986

전보(前報)에 이어 우리나라 전국(全國) 60개(個) 밭 토양(土壤)에서 분리(分離)한 토착근류균(土着根瘤菌)을 대두작부형별(大豆作付型別)로 구분(區分)하여 질소고정력(窒素固定力) 및 몇가지 생리적(生理的) 특성(特性)을 비교(比較) 검토(檢討)한 결과(結果)는 다음과 같다. 1. 토착근류균(土着根瘤菌)을 대두재배지(大豆栽培地)로 부터 133개균주(個菌株), 무재배지(無栽培地)에서 125개균주(個菌株)를 분리(分離)하여 free-living 상태(狀態)에서 아세칠렌 환원력(還元力)을 측정(測定)한 결과(結果), 전자(前者)에서 12.8%, 후자(後者)에서는 6.4%로 평균(平均) 9.7%가 4n mole $C_2H_4$/tube/hr 이상(以上)의 아세칠렌 환원력(還元力)을 보였다. 2. 토착근류균(土着根瘤菌)의 분리(分離) 326개(個) 균주(菌株)를 litmus milk 검정(檢定)으로 산(酸) 및 알카리 생성반응(生成反應)을 조사(調査)한 결과(結果), 산(酸) 생성균(生成菌)은 대두재배지(大豆栽培地)에서 분리(分離)한 균(菌)은 34%, 무재배지(無栽培地)의 분리균(分離菌)은 20%였으나, 알카리 생성균(生成菌)이 산(酸) 생성균(生成菌) 보다 두 토양(土壤) 모두 많았다. 또한 토착근류균(土着根瘤菌)중 serum zone 양성균주(陽性菌株)는 대두무재배지(大豆無栽培地)의 분리균(分離菌)에서 68%, 대두재배지(大豆栽培地)의 분리균(分離菌)이 47%로서 대두무재배지(大豆無栽培地)의 분리균(分離菌)에서 많은 serum zone 양성반응(陽性反應)을 보였다. 3. 토양심층별(土壤深層別) 토착근류균수(土着根瘤菌數)는 하층토 보다 표토층에서 현저(顯著)히 많았으나, 작부형간(作付型間)에는 큰 차이(差異)가 없었다. 그러나 이들 균수(菌數)중 대두(大豆)에 감염(感染)할 수 있는 토착대두근류균(土着大豆根瘤菌)은 대두재배지(大豆栽培地)에서 2.3~23.0 cells/g soil, 대두무재배지(大豆無栽培地)에서 0.9~9.2 cells/g soil로서 표토층에서 하층토로 갈수록 현저(顯著)히 감소(減小)하였다.