• Proceedings of the Microbiological Society of Korea Conference
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• 2008.05a
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• pp.144-146
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• 2008

• Proceedings of the Microbiological Society of Korea Conference
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• 2007.05a
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• pp.65-67
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• 2007

• Korean Journal of Microbiology
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• v.12 no.1
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• pp.15-24
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• 1974

This experiment has been carried out with a view to elucidating the distribution of Azotobacter and their population size in rhizosphere and sea and designed ro compare the results with some environmental factors. Results of the experiment are summarized as follows: 1) It was observed that the population sizes of Azotobacter were decided upon the moisture content of soil and that the soil pH was one of the most impertant factors influencing the distribution of Azotobacter. 2)Population sizes of Azotobacter in rhizosphere were changed in accordance with the kinds of vegetation on soil: The rhizosphere where bamboo, corn, legume, and oak inhabit showed the largest population size of Azotobacter. On the other hand, rhizosphere of ginseng revealed no Azotobacter. However, the largest population of general fungi were measured at the rhizosphere. 3)Comparing the population sizes of general microbes in rhizosphere with those of non-rhizosphere, the population sizes of microbes in rhizosphere are larger than those of non-rhizosphere. 4)In coastal environments, population sizes of Azotobacter in surface water of sea are similar to those of the soil(mud) of tidal land. But the sizes are generally smaller than those of terrestrial soils.

• Proceedings of the Microbiological Society of Korea Conference
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• 2005.05a
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• pp.199.2-199
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• 2005

• Journal of Environmental Health Sciences
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• v.38 no.3
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• pp.241-250
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• 2012

Objectives: This study was performed to investigate hygienic behavior of food handlers and general population focusing on awareness of hand-washing and the microbial load of their hands. Methods: A questionnaire survey and microbiological analysis were carried out for sixty-four people each. Samples for microbiological analysis were collected through the glove-juice method from the hands, and were analyzed for the presence of aerobic plate counts, total coliform, fecal coliform, Escherichia coli, Staphylococcus aureus, and Salmonella spp. according to the Food Code of Korea. Results: In the survey, significant differences between the food handlers and general population (p < 0.01) were found in hand-washing frequency, duration, use of hand-washing agents, washing parts of hands, hand-drying method, and method of turning off water. In eight different situations among the ten particular situations in their daily life, more food handlers responded to wash their hands than general population (p < 0.05). Bacterial load on hands with general population was consistently higher than with food handlers (p < 0.05), however, percentages of positive hands of S. aureus and Salmonella spp. were not. Conclusions: Poor hand hygiene practices were indicated by the positive results for E. coli, S. aureus, and Salmonella spp. on the hands of some respondents in both groups. This study reveals that there is the need for programs or campaigns to increase hand-washing practices of both groups.

• The Korean Journal of Food And Nutrition
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• v.21 no.2
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• pp.176-183
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• 2008

This study examined the anti-microbiological effects of chlorine treatment on the surface of fresh fruits, in order to improve microbiological safety in school foodservice operations. Non-peeled fruit(strawberries) and peeled fruit(bananas) were treated with different concentrations of chlorinated water and rinsing numbers, followed by microbiological testing. The fruits were immersed at different concentrations of chlorinated water(0 ppm, 50 ppm, and 100 ppm) and durations(3 min and 5 min), and were then rinsed with tap water(one time, two times, or three times). The total viable cell counts of both the strawberries and bananas ranged from $10^3$ CFU/g to $10^4$ CFU/g, and coliform levels ranged from $10^2$ CFU/g to $10^3$ CFU/g. As the chlorine concentration, immersion time, and rinsing number increased, anti-microbiological activity increased. The largest microbial reduction was shown with immersion for 5 min in 100 ppm chlorinated water and three rinsings. In the strawberries, this treatment reduced the initial population of total viable cells and coliforms by 3.29 log CFU/g and to an undetectable level, respectively, no total viable cells or coliforms were detected on the banana surface following this treatment. However, after a sterilization treatment with immersion for 5 min in 50 ppm chlorinated water and three rinsings, the total viable cell counts and coliform counts of the strawberries and bananas decreased to acceptable levels, based on the microbiological standards for ready-to-eat foods. Overall, it was shown that the sterilization treatment of 50 ppm chlorinated water, soaking for 5 min, and three rinsings provided an effective reduction in surface microbes, and enhanced the microbiological safety of the fruit.

• Journal of Environmental Health Sciences
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• v.43 no.6
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• pp.499-508
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• 2017

Objective: This study was conducted to investigate changes in microbiological quality according to various storage conditions in the drinking process of bottled mineral water. Methods: Heterotrophic plate counts ($21^{\circ}C$ and $36^{\circ}C$) and pathogenic indicators (total coliforms, fecal Streptococcus, Pseudomonas aeruginosa, Clostridium perfringens, Salmonella, and Shigella) were analyzed in commercial bottled mineral water stored under different conditions ($4^{\circ}C$, $20-25^{\circ}C$, $36^{\circ}C$) after injecting saliva. The heterotrophic plate counts were analyzed twice per day for the first week and once per day for the three weeks after. Pathogenic indicators were analyzed at the beginning and end (initial and final). Results: The results of the microbiological quality of the bottled mineral water in contact with saliva showed that heterotrophic plate counts ($21^{\circ}C$) had a tendency to be sustained or decrease slightly after 10 days. Heterotrophic plate counts ($36^{\circ}C$) had a high population in the initial samples and gradually decreased at $4^{\circ}C$ storage, but it remained constantly high in storage at $20-25^{\circ}C$ and $36^{\circ}C$. In the general drinking condition, the population was slightly higher than the control, but the overall trend was similar. Conclusions: As a result of the microbiological quality of mineral bottled water in contact with saliva during the process of drinking, heterotrophic plate counts ($21^{\circ}C$ and $36^{\circ}C$) showed a high population compared to the control, which was only opened and not in contact with saliva. In some samples, pathogenic indicators were also detected. Therefore, it is desirable to consume bottled mineral water as soon as possible after opening.

• Korean Journal of Food Science and Technology
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• v.41 no.4
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• pp.452-457
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• 2009

In order to secure microbiological safety and quality of commercial vegetable sprouts, buckwheat seeds and sprouts were investigated for their microbiological flora and for the effect of chlorine treatment on quality. Microbiological analyses showed that major inherent bacteria including Enterobacter, Sphingomonas, and Klebsiella were found in commercial buckwheat sprouts with a population size ranging from $10^5$ to $10^7$ CFU/g. In addition, buckwheat seeds had a similar microbial flora to sprouts. Foodborne pathogenic bacteria such as Escherichia coli O157:H7, Staphylococcus aureus, Salmonella Typhimurium, and Listeria monocytogenes were not detected in the sprout or in the seed samples. Chlorine treatment with 50-150 ppm sodium hypochlorite noticeably reduced viable bacteria cell counts of the sprouts by about 1 log. However, no significant difference was observed among the different chlorine concentrations. After storage for 7 days at $5^{\circ}C$, the sprouts treated with 100-150 ppm chlorine showed higher sensory scores in visual quality than the others (p<0.05). The results indicated that proper pretreatment, such as dipping in chlorinated water, could confer a beneficial effect on the microbiological safety and visual quality of buckwheat sprouts.

• Korean Journal of Microbiology
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• v.9 no.2
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• pp.47-54
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• 1971

This study is concerned to the microbial population and its effects in the fish paste products. Experimental results were summarized as following orders ; 1) The number of bacteria in accordance with raw materials and coocking site waas known to as ; Wheat flor - $7.0{\times}10^8$/gram , Brayed fish meat - $2.0{\times}10^7$/gram, Cooking table - $6.1{\times}10^6$/$1.54cm^2$Chopped fish meat -$4.1{\times}10^6$/gram, Wooden plate - $5.5{\times}10^5$/218.32cm, Sodium chloride - $8.8{\times}10^4$/gram, Wheat starch - $4.5{\times}10^4$/gram, Fish meat - $2.3{\times}10^4$/gram. However, there were a few bacterial numbers less than 300 per gram of raw materials, such as monosodium glutamate, tap water, sugar, saccharine and eggs. 2) Bacterial population in the raw materials might be changed according to the conditions of preservation. 3) When the heat tratment is used for the preservation, the thermal effects were rarely found at the interior part of fish paste products. Conduction of heat into the interior part dose not rise about $84^{\circ}C$ and the survival of bacteria could be possible under the condition. Therefore, cooking being used requires further studies. 4) Number of bacteria in the fish paste products sold in the market was higher on April and May than those on June. Especially on June, the number of bacteriz in the interior part were found higher than those in the exterior part of the products.

• Korean Journal of Microbiology
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• v.15 no.1
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• pp.20-30
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• 1977

Relationship of soil properties and seasonal variation on microbilogical population to-continuous culture and first-time culture of ginseng was investigated by bimonthly from May 1976 to January 1977. pH and P contents of 2 years continuous culture of soil were higher than other culture plot of soil, and contraty to the above, 2 years first-time culture of ginseng soil was conplot of soil, and contraty to the above, 2 years first-time culture of ginseng soil was contained more potassium contents than other culture plot of soil. In microbiological fluctuation with seasonr in various soil conditions, the population, trends of Fusarium spp., Erwiniaspp., and flourescent Psedudomonas spp. were increased in May and July in general, but decreased in the other month. It was observed that in all type of soil, Fusarium spp. was distributed in abundance in and on rihizosphere, and decreased the propagules numbers as soil depth increase. The numbers of Erwinia spp. and fluorescent Pseudo-monas spp. were distributed greater in numbers on the surface zone of soil depth decreasing the numbers along the soil layer increase, and also in 2years continuous culture of soil especially, a great numbers of Erwinia spp. and fluorescent Pseudomonas were evenly distributed in surface zone and rhizosphere. Ginseng disease with a high incidence of bacterial disease in continuous culture of 2 and 4 years was seemed to be associated with soil bacteria that was high in numbers of Erwinia spp. and fluorescent Pseudomonas spp. in May and July.