• Journal of Wetlands Research
• /
• v.7 no.2
• /
• pp.37-52
• /
• 2005

Vertical distribution of bacterial population and activities were compared between the muddy and sandy sediment of the tidal flat located in southern area of Ganghwa Island. The average of bacterial number and activities in mud flat was slightly higher than that in sand flat. Bacterial number was markedly increased at the sandflat during the investigation period, which seemed to be the result of increase of mud content. The number and activities of microorganisms in mudflat was comparable to that of the mangrove sediments. There was no differences in bacterial number with the depth, but the aminopeptidase activity and bacterial productivity were decreased markedly within 3~5cm depth of sediment due to the availability of carbon sources and molecular oxygen in pore water. The number and activities of microorganisms in mudflat did not correlated with the distribution of benthic microalgae; however, those in sand flat were closely correlated with the distribution of benthic microalgae. The distribution of marsh plant in the mudflat area might be the reason of the difference.

• Korean Journal of Microbiology
• /
• v.37 no.1
• /
• pp.80-84
• /
• 2001

Vertical and temporal variations of active and total bacterial abundance were monthly estimated in Lake Soyang from April 1999 to January 2000. The number of total and respiring bacteria was determined directly under microscope by AODC and CTC methods, respectively. The number of total and active bacteria varied from $2.1{\times}10^5 to 3.1{\times}10^6 $,$cells{\cdot}ml^{-1}$ and $1.8{\times}10^4 to 8.0{\times}10^5 $,$cells{\cdot}ml^{-1}$, respectively. The proportions of respiring bacteria to total cell ranged from 3.7 to 44.2% : The proportions was the highest in November 1999 and the lowest in December 2000. The specific activity of${\beta}$-glucosidase divided by total bacteria was$1.6{\times}10^5\;amol{\cdot}cell^{-1}{\cdot}hr^{-1}$in August and$1.4{\times}10^5\;amol{\times}cell^{-1}{\times}hr^{-1}$in September while the specific activity divided by CTC active bacteria was about$3.6{\times}10^5\;amol{\cdot}cell^{-1}{\cdot}hr^{-1},\;24.0{\times}10^5\;amol{cdot}cell^{-1}{cdot}hr^{-1}$. The specific activity of active bacteria in September was 6.7 times higher than that of August. By these data of active bacteria, the new information of aquatic ecosystem was unveiled.

• Proceedings of the Korea Society of Environmental Biology Conference
• /
• 2002.05a
• /
• pp.14-14
• /
• 2002

• Journal of Life Science
• /
• v.14 no.1
• /
• pp.163-166
• /
• 2004

To investigate the bacterial growth on granular activated carbon (GAC) for the purification of tap water, fixed bed columns with GAC were installed and operated at an empty bed contact time (EBCT) of 1 min$\pm$0.08 min. There was no bacterial breakthrough in the spring. However, the bacterial concentrations of effluent (($10^3$ CFU/ml) were higher than that of the influent ($10^2$ CFU/ml) after 10 day operation in summer. More bacteria were enumerated near the entering point of the tap water, while the bacterial activities were similar throughout the columns. Different bacterial species were detected on coal- and plant-based GAC, although the dominant genus was the same as Acinetobacter.

• KSBB Journal
• /
• v.19 no.2
• /
• pp.104-109
• /
• 2004

Activated carbon has been used in water treatment, because they strongly adsorb organic material including contaminant. Water purifier usually use activated carbon, and bacterial regrowth on that could induce many problems. Model columns, packed with coal- and plant-based granular activated carbon (GAC), were operated with rechlorinated tap water to compare the degree of bacterial regrowth on different GACs. GAC columns decreased the concentration of total organic carbon and chlorine, while they are not good for the decrease of ions. Breakthrough of bacteria were occurred after eight days of operation, and reached 1.1 ${\times}$ 10$^3$ CFU/mL on coal based GAC and 6.2 ${\times}$ 10$^2$ CFU/mL on coconut based one. Bacterial activities on GAC were between 15.35 ∼ 29.06 $\mu\textrm{g}$ INT-formazan/g-GAC/h. Bacterial concentration and activities were higher in coal based GAC than coconut based one. Bacterial regrowth on GAC was clarified and regrowth effect of coal-based GAC was higher than that of coconut-based one.

• Microbiology and Biotechnology Letters
• /
• v.37 no.4
• /
• pp.340-349
• /
• 2009

A CJ9 bacterial strain, which showed antifungal and antibacterial activities, was isolated from meju and identified as Bacillus polyfermenticus based on Gram staining, biochemical properties, as well as its 16S rRNA sequence. B. polyfermenticus CJ9 showed the antimicrobial activity against the various pathogenic molds, yeasts, and bacteria. The antibacterial activity was stable in the pH 5.0~9.0, but the activity was lost at $37^{\circ}C$ for 24 hr. The antifungal activity was stable in the pH range of 3.0~9.0 and reduced at $121^{\circ}C$ for 15 min, but antifungal activity was not completely destroyed. The antibacterial activity was completely inactivated by proteinase K, protease, trypsin, and $\alpha$-chymotrypsin. The antifungal activity was also completely inactivated by protease and $\alpha$-chymotrypsin, and reduced its activity by proteinase which indicated that the antifungal and antibacterial compounds have proteineous nature. The apparent molecular mass of the partially purified antifungal compound, as indicated by using the direct detection method in Tricine-SDS-PAGE, was approximately 1.4 kDa. The molecular mass of the antibacterial compound could not be determined because of its heat-liable characteristic.

• Korean Journal of Microbiology
• /
• v.35 no.2
• /
• pp.128-132
• /
• 1999

The effects of diet on the composition of fecal microflora in mouse and the aclivilies of several enzymes in the leces were investigated. Vegetarian dietary groups were found to contain about ten lines higher numbers of Locmbocillus and B$&bacterizml than animal dietary groups. An~rnal dietmy groups were found to contain about 5 tolo times higher numbers of anaerobic Closhidia and Bocieriocles than the vegeterian detary groups. Fccal microbial $\beta$-glucosidase, $\beta$-glucm'onidase, ii-yptophanase and orease activilies in ihe animal dietary groups were shown lo be 30 to 50% hgher than those in h e vegetarian detary groups.

• Proceedings of the Plant Resources Society of Korea Conference
• /
• 2022.09a
• /
• pp.120-120
• /
• 2022

장내세균의 구성과 각종 질환의 상관관계에 대한 연구가 활발히 수행되고 있다. 대장관련 질환 뿐 아니라, 당뇨, 비만 등 대사성 질환, 심지어 정신질환에까지 장내세균 구성의 영향이 미치는 것으로 밝혀졌다. 이에 다양한 천연 소재를 활용하여 각종 동물질환모델에서 생리활성을 검토할 때, 장내세균의 구성을 분석하여 그 상관관계를 밝힐 필요가 있다. 장내세균의 구성에 따라 질환의 양상이 달라질 수 있으며, 치료에 영향을 줄 수 있다. 동물실험을 수행할 때에도 실험동물 간 장내세균의 구성이 다르면 질환의 유도 또는 천연소재에 의한 치료 패턴이 달라질 수 있음을 가정하여 본 연구를 수행하였다. 본 연구에서는 EtOH와 LPS를 이용하여 간장해 동물모델을 구축하고, 장내세균 구성을 T-RFLP법으로 분석하여 그 상관관계를 검토하였고, tracheloside 등의 천연물을 투여함으로써 성분의 대사 패턴을 확인하였다. 이 결과는 천연소재의 간장해 개선 연구를 수행하기 위한 기초 결과로 활용될 수 있다.

• Korean Journal of Microbiology
• /
• v.47 no.1
• /
• pp.50-55
• /
• 2011

A simple and rapid method was developed for monitoring of Gram-positive bacteria in the wastewater treatment system. Culture suspensions of 4 Gram-positive and 4 Gram-negative strains were filtrated and stained with a polyethersulfone membrane filter and Toluidine Blue-O. To establish quantitative color image analysis, the intensity value of RGB (red-green-blue) color of a scanned filter image was analyzed with a photographic program. Red and green color values of Gram-positive bacteria were higher than those of Gram-negative bacteria. This method was applied to the activated sludge mixed with the Gram-positive bacteria. Although evaluation was difficult due to the irregular size and shape of flocs, the population of Gram-positive bacteria in the activated sludge could be monitored with floc dispersion technique. The more amounts of Gram-positive bacteria in the activated sludge led to the increase of red and green color values. This method provides a rapid and quantitative measurement of Gram-positive bacteria within the wastewater treatment systems.

• Korean Journal of Environmental Biology
• /
• v.17 no.1
• /
• pp.59-69
• /
• 1999

Bacterial population, signal compounds of pollution, bacterial productivity, heterotrophic activity and the activities of extracellular enzymes were analyzed four times from July 1994 to April 1995 at Daejin, Galnam, Pohang, and Ulsan in the coastal area of Bast Sea in order to investigate the state of eutrophication. The population of heavy metal resistant bacteria in Pohang was the highest among all stations. The bacterial populations which could utilize C -P compounds (phosphonate) showed the highest at Pohang that was expected for the industrial and agricultural effluents to inpour. It could be useful as an index of expectation about the influx of industrial sewages and agricultural effluents. The activities of extracellular enzymes for the degradation of organic matter were the highest in the Ulsan Chuyongam, but low in Daejin. These results showed positive relationship with the population of heterotrophic bacteria and bacterial productivity The ratio of poly-P and DNA in Pohang was the highest, and that in Ulsan, Galnam, and Daejin consecutively, corresponding with the distribution of heterotrophic bacteria. In case of the heterotrophic activities, each of the stations gives difference of seasonal variation in heterotrophic activities. Bacterial productivity seemed to be dependent on seasons; the highest in summer and the lowest in fall and winter. These seasonal variations of bacterial productivity seems to be similar with those of heterotrophic bacteria. It is suggested that the state of eutrophication could be evaluated by the criteria of the population sizes and the productivities of microorganisms, the amount of poly-P, heterotrophic activity, the activities of extracellular enzymes, etc.