• 미생물학회지
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• 제29권5호
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• pp.329-338
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• 1991

From July 1985 to December 1986, 28 variables of phycal-chemical factors, bacteria and heterotrophic activity were investigated 17 times at 3 stations in the estuary of Naktong River and the influences of environmental factors to bacterial population and heterotrophic activity were analyzed through multiple regression. The results of multiple regression were as follows. At station 1, total bacteria and heterotrophic bacteria(Z-25) could explain 57% of the variation of maximum uptake velocity for glucose and 54% of turnover time for glucose was explained by total coliform bacteria and MBOD, Sixty four percent of the variation of Kt+SN was accounted for salinity, MBOD-N and inorganic phosphate. Turnover rate for acetate was also accounted for the change of MBOD-P by 56%. At station 2 maximum uptake velocity for glucose depends on MBOD-N by 81%; turnover time on bacteria by 50%; Kt+Sn on avilable nutrient by 61%. More than 50% of maximum uptake velocity and turnover time for glucose were influenced by bacteria and that of Kt+Sn by the change of nutrient in the surface water of station 3. In the bottom water of station 3, the change of maximumuptake velocity, turnover time and Kt+Sn for glucose was controlled by total bacteria and available nutrient, bacteria, the change of nutrient salts respectively. On the whole, more than 50% of maximum uptake velocity and turnover time for glucose could be due to the change in the number of bacetria and the value of Kt+Sn was affected by the change of nutrient salts. Turnover rate for acetate was controlled by available phosphate at station 1 and by bacteria at station 2 and 3, which showed a distinct difference between the environmental factors which govern the rate of glucose and acetate uptake in the Naktong esturine ecosystem. And bacterial communities were controlled by available nutrients at station 1, by nutrient salts and salinity at station 2 and in the surface water of station 3 and by salinity in the bottom water of station 3.

• Applied Biological Chemistry
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• 제38권2호
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• pp.95-99
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• 1995

전국 각지에서 수집한 누룩 27개 시료에 대해서 젖산균수 및 총균수를 조사하고 젖산균을 분리, 동정하였다. 젖산균수 및 총균수의 평균치는 각각 $2.12{\times}10^7$ cfu 및 $2.08{\times}10^8\;cfu/g$이었으며 시료에 따라 젖산균수는 큰 차이가 없으나 총균수에 있어서는 큰 차이를 나타내었다. 젖산균 중 구균이 $70{\sim}95%$를 차지하였으며 분리된 32균주는 Leuconostoc mesenteroides subsp. mesenteroides (11균주), Pediococcus (7균주), Lactobacillus plantarum (3균주), L. murinus (7균주) 및 Enterococcus (4균주)로 동정하였다(1995년 1월 19일 접수, 1995년 2월 16일 수리).

• 한국수산과학회지
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• 제54권2호
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• pp.224-230
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• 2021

This study assessed the contamination levels of total aerobic bacteria, fungi, coliforms, Escherichia coli, and Staphylococcus aureus, and qualitative analysis of Bacillus cereus, Salmonella spp., Listeria spp., and Vibrio spp. in four frozen-raw sliced fishes (cuttlefish, flatfish, salmon, and shrimp) for sushi production. The total aerobic bacteria, fungi, and coliforms were 2.95-3.38, 1.96-2.88, and 0.92-1.29 log CFU/g, respectively. In particular, shrimp was highly contaminated with total aerobic bacteria (3.38 log CFU/g) and fungi (2.88 log CFU/g). Over 3 log CFU/g of total aerobic bacteria was also detected in cuttlefish, flatfish, and salmon. Less than 1-2 log CFU/g of E. coli was detected in all frozen samples. S. aureus was detected at 2.25-3.13 log CFU/g in most samples. B. cereus was qualitatively detected at 25% in most samples, except for salmon (0%). Salmonella spp., L. monocytogenes, and Vibrio spp. were qualitatively detected at 25-50% of all four samples. The microbial contamination levels determined in the current study may be potentially used as basic data to perform microbial risk assessments of frozen-raw sliced fishes.

• 한국초지조사료학회지
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• 제39권3호
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• pp.132-140
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• 2019

Fermented total mixed ration (TMR) is a novel feed for ruminants in South Korea. The purpose of this study was to evaluate the effects of lactic acid bacteria (LAB) on the quality of TMR and in vitro ruminal fermentation. Strains of three LAB spp. (Lactobacillus plantarum, L. brevis, L. mucosae) were used in fermentation of TMR. Inoculations with the three LAB spp. lowered pH and increased concentrations of lactic acid, acetic acid, and total organic acid compared to non-LAB inoculated control (only addition of an equivalent amount of water) (p<0.05). Bacterial composition indicated that aerobic bacteria and LAB were higher. However, E. coli were lower in the fermented TMR than those in the control treatment (p<0.05). Among the treatments, L. brevis treatment had the highest concentration of total organic acid without fungus detection. Gas production, pH, and ammonia-nitrogen during ruminal in vitro incubation did not differ throughout incubation. However, ruminal total VFA concentration was higher (p<0.05) in the LAB spp. treatments than the control treatment at 48 hours. Overall, the use of L. brevis as an inoculant for fermentation of high moisture. TMR could inhibit fungi growth and promote lactic fermentation, and enhance digestion in the rumen.

• 한국환경보건학회지
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• 제31권1호
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• pp.79-85
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• 2005

This study was undertaken to investigate the changes of index microorganisms and lactic acid bacteria of traditional Korean fermented vegetables (kimchi) during the ripening and fermentation period. A type of kimchi, baechoo-kimchi, was prepared and stored at $10^{\circ}C$ for 8 days. The numbers of the total aerobic bacteria, psychrotrophilic bacteria, coliform bacteria, and Escherichia coli in the kimchi and also in raw materials of the kimchi (Chinese cabbage, green onion, ginger, garlic, and red pepper) were counted using appropriate media. The highest number of aerobic bacteria was detected from ginger, then red pepper, then garlic, then Chinese cabbage, and lowest number from green onion. The highest number of psychrotrophilic bacteria was detected from red pepper, then Chinese cabbage, then garlic, then ginger, and the lowest number from green onion. Coliforms and E. coli were not detected from all of the raw materials of kimchi. Total aerobic bacteria and lactic acid bacteria of the kimchi showed gradually increasing during ripening and fermentation. The number of psychrotrophilic bacteria showed a similar level in the kimchi. Coliform bacteria were detected at the 3rd, 4th, and 5th day of the kimchi fermentation period, although they were not detected from the raw materials of the kimchi. However, the bacteria were not detected in the kimchi after 6 days. E. coli was not detected in all kimchi samples. The pH value of the kimchi gradually decreased, and acidity increased over fermentation period. This study indicates that there was contamination of coliform bacteria during the process of kimchi preparation, and lactic acid bacteria proliferated in the kimchi during fermentation inhibited the growth of coliforms. More research is needed to evaluate the inhibitory effects of each raw materials of kimchi.

• 한국산업보건학회지
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• 제16권1호
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• pp.1-10
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• 2006

Concentration and identification of airborne bacteria in the regulated public facilities were examined with the six-stage cascade impactor. Geometric mean total and respirable concentrations of airborne bacteria were $404cfu/m^3$ and $194cfu/m^3$ in hospital, $931cfu/m^3$ and $358cfu/m^3$ in kindergarten, $294cfu/m^3$ and $134cfu/m^3$ in day-care center, and $586cfu/m^3$ and $254cfu/m^3$ in postpartum nurse center, respectively. As a result, culturable total and respirable concentrations of airborne bacteria were significantly highest in kindergarten and lowest in day-care center (p<0.05). The ratio of respirable to total concentration of airborne bacteria in the investigated public facilities was ranged from 30% to 40% but there was no significant difference among them (p>0.05). The mean I/O ratio of culturable total and respirable concentrations were 0.58 and 0.66 in hospital, 0.71 and 0.83 in kindergarten, 0.28 and 0.41 in day-care center, and 0.63 and 0.78 in postpartum nurse center, respectively. Day-care center showed the lowest I/O ratio of culturable total and respirable concentration of airborne bacteria (p<0.05) but a significant difference was not found among other facilities. Indoor concentration of airborne bacteria did not correlated significantly with indoor temperature and relative humidity (p>0.05) but had a significant positive correlation with $CO_2$ and surrounding condition (p<0.05). Staphylococcus spp., Micrococcus spp., Corynebacterium spp., and Bacillus spp. were dominant genera and amounted to over 95% of total airborne bacteria identified in the investigated public facilities. Size distributions of four dominant genera did not observed inconsistently regardless of type of public facility.

• 미생물학회지
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• 제51권1호
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• pp.21-30
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• 2015

본 연구는 논과 밭 토양의 황산염 환원세균의 군집구조와 T-RFLP 패턴을 조사한 논문으로, 유기 농법 토양과 관행 농법 토양 그리고 밭 토양 총 3종류의 토양을 8월과 11월에 채집하여 실험하였다. 토양 성분 분석 결과 총 질소, 총 탄소, 총 인의 값은 모든 토양이 비슷하게 나타났고 계절별로는 수분의 함량은 8월에, 총 탄소는 11월에 가장 높게 나타났다. 황산염 환원세균은 초산보다 젖산을 기질로 이용하는 황산염 환원세균이 더 많이 분포하고, 유기 농법 토양에 황산염 환원세균이 가장 많이 분포하는 것으로 나타났다. 각 토양에서 얻은 총 181개 클론으로 계통학적 분석을 한 결과, 대부분의 클론들은 배양 가능한 황산염 환원세균과는 매우 낮은 상동성을 보였으나, 자연계에서 확인되는 클론들과는 90% 이상의 높은 상동성을 나타내었다. T-RFLP 분석 결과 91, 357, 395, 474 bp의 분포가 가장 높았고, 계절에 따라 황산염 환원세균의 군집 구조가 달라지는 것을 확인하였다.

• 한국환경보건학회지
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• 제39권5호
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• pp.447-455
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• 2013

Objectives: This study aims to understand the concentration, diversity, and antibiotic characteristics of staphylococci present in the indoor air of child-care facilities. Methods: Air sampling was performed from October 2012 to January 2013 in 120 child-care facilities in Seoul, Korea. Methicillin-resistant bacteria were selected from the total obtained airborne bacteria and subjected to 16S rRNA analysis for methicillin-resistant staphylococcal species determination. Identified staphylococcal strains were tested for resistance to a range of antibiotics. Results: Average total airborne bacterial concentration was $508.9{\pm}246.3CFU/m^3$. Indoor concentration of total airborne bacteria had a significant positive correlation with the $CO_2$ concentration in the child-care facilities. Methicillin-resistant staphylococci were present in 13.3% of the child-care facilities studied. A total of four species (S. epidermidis, S. cohnii, S. saprophyticus, S. sp.) and 55 strains were identified from the indoor air of the child-care facilities. Staphylococcus cohnii was the most common species (54.5%), followed by S. epidermidis (38.2%). All of the isolated staphylococcal strains exhibited high resistance to oxacillin, erythromycin, mupirocin, and ceftizoxime. Especially, S. saprophyticus strains showed more multidrug resistance to oxacillin, vancomycin, clindamycin, erythromycin, lincomycin, ceftizoxime, mupirocin, and tetracycline than did other species. Conclusion: The results of this study showed that a monitoring system for multidrug-resistant bacteria is needed in facilities for children, as the community-associated infections of these bacteria are increasing.

• Environmental Engineering Research
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• 제14권1호
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• pp.19-25
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• 2009

In this study, total bacteria, enteric members of the $\gamma$-proteobacteria, and microbial communities in seawater were analyzed as indirect indicators for quantifying biofouling. Biomass in seawater can significantly affect feed water pretreatment and membrane biofouling of reverse osmosis desalination processes. The purpose of this paper is to investigate microbiological quantity and quality of seawater at the potential intake of a desalination plant. For this analysis, the total direct cell count (TDC) using 4'-6-diamidino-2-phenylindole (DAPI)-staining and DNA-based real-time PCR were used to quantify the total bacteria and relative content of enteric members of $\gamma$-proteobacteria in seawater, respectively. In addition, microbial communities were examined using 16S rRNA gene cloning and bacterial isolation to identify the most abundant bacteria for a further biofouling study. The experimental results of this study identified about $10^6$ cells/mL of (total) bacteria, $10^5$ 16S rRNA gene copies/mL of enteric $\gamma$-proteobacteria, and the presence of more than 20 groups of bacteria.

• 한국식품영양학회지
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• 제9권3호
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• pp.289-293
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• 1996

Population changes of aerobic bacteria and lactic acid bacteria and changes of pH, acidity, and total sugar content were creased from initial period of fermentation. Lactic acid bacteria Increased during the first one nay rapidly and thereafter they creased slowly thereafter. Acidity increased on the third day of fermentation. Acidity was very low In Kimchi containing both Total sugar content decreased gradually from initial period to late period of fermentation.