• Korean Journal of Clinical Laboratory Science
• /
• v.50 no.1
• /
• pp.11-19
• /
• 2018

The gut microbiome has been studied extensively over the past decade with most scientific reports focused on the adverse role of the gut microbiome on gastrointestinal diseases. For example, the altered gut microbiome exacerbates the development of immune system-mediated damage in many diseases. The most studied pathologies include irritable bowel syndrome, inflammatory bowel diseases, and colitis-associated cancer. On the other hand, intestinal microflora is also beneficial and contributes to the intestinal physiology by the synthesis of vitamins, production of short chain fatty acids and bile acid metabolism, thereby maintaining gut homeostasis. Therefore, the balance between commensal and pathogenic bacteria populations influences mainly the maintenance of intestinal health. Changes in the intestinal microflora have been suspected to be the underlying causes of multiple diseases. Despite the immense amount of published data, the optimal gut microbiome composition is still controversial. This review briefly outlines the connection between the gut microbiome and critical gastrointestinal diseases focusing on three prominent intestinal disorders: irritable bowel syndrome, inflammatory bowel diseases, and colitis-associated cancer disorders. Finally, intervention strategies using natural products for the alleviation of these diseases and the maintenance of a health gut microbiome are suggested.

• KOREAN POULTRY JOURNAL
• /
• v.33 no.8 s.382
• /
• pp.121-125
• /
• 2001

건강한 닭은 병원성 미생물에 대하여 자연적인 저항성을 가지고 있다. 이것은 숙주상태와 장관사이에 서로 밀접한 협력장치가 있기 때문이며 건강한 병아리는 부화된 후 지속적으로 장관내에서 정상적인 세균총을 형성한다.

• The Journal of Natural Sciences
• /
• v.16 no.1
• /
• pp.143-154
• /
• 2005

To define the ecological roles of bacterial community in Daechung Reservoir. Vertical variation of total bacterial numbers were estimated at MAN site for one year with DAPI staining. The bacterial numbers were counted, environmental factors were monitored at the surface, -5m, -10m, -15m and -25 m of MAN sited and tried to explain the vertical bacterial numbers with environmental factors. The bacterial number was $1.6-1.7.0 x10^6$ cells/ml at the surface, $2.3-11.0x10^6$ cells/ml at 5 m depth, $1.2-1.4.0x10^6$ cells/ml at 10 m depth, $1.4-15.0x10^6$ cells/ml at 15 m depth and $1.4-1.3.0x10^6$ cells/ml at 25 m depth. The Mean bacterial number at the surface was more that those at any other depth. The explanation of the vertical total bacterial numbers with environmental factors were suggested.

• 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.

• Korean Journal of Microbiology
• /
• v.28 no.3
• /
• pp.204-209
• /
• 1990

The total and heterotrophic bacterial distributions, compositions and alkaline phosphatese actibities were analyzed in Lake Soyang from Sep. 1987 to Aug. 1988. The heterotrophic bacteria was small portion, 0.07-2.63% of total bacterial number which ranged from $3.2{\times}10^{5}$ to $3.2{\times}10^{6}$ cells/${\mu}\ell$. The composition of bacterial community was less diverse in summer and at the fish farm site and Peridinium blooming site. Pseudomonas and Flavo bacterium were the dominant genera in all sites. The highest proportion and activity of alkaline phsophatase was appeared in Flavobacterium, while Pseudomonas was the most predominant group.

• Korean Journal of Microbiology
• /
• v.51 no.1
• /
• pp.21-30
• /
• 2015

The goal of this study was to identify relationships between the composition of sulfate reducing bacterial assemblages and terminal restriction fragment length polymorphism (T-RFLP) patterns in rice paddy and dry farming soils. Samples of organic farming soils, conventional farming soils, and dry field farming soils were collected in August and November. Analyses of the soil chemical composition revealed similar total nitrogen, total carbon and total inorganic phosphorus levels; however, the moisture content and total carbon were higher than in the other soils in both August and November, respectively. Sulfate reducing bacteria utilizing lactic acid were more widely distributed than those that used acetic acid, and the number of sulfate reducing bacteria in organic farming soil was most abundant. Phylogenetic analysis based on 181 clones revealed that most showed low similarity with cultured sulfate reducing bacteria, but more than 90% similarity with an uncultured sulfate reducing bacteria isolated from the environment. T-RFLP analysis revealed that fragments of 91, 357, 395, and 474 bp were most common, and the community structure of sulfate reducing bacteria changed seasonally.

• Korean Journal of Microbiology
• /
• v.43 no.1
• /
• pp.14-18
• /
• 2007

The bacterial community structures at 2 sponge species belonging to the genus Baikalospongia and Lubomirskia in Lake Baikal were analyzed with fluorescent in situ hybridization (FISH) method. The total bacterial numbers in the genus Baikalospongia ranged from $7.2{\times}10^{7}\;to\;4.2{\times}10^{8}\;cells/ml$, and those in Lubomirskia from $1.2{\times}10^{8}\;to\;1.6{\times}10^{8}\;cells/ml$, while those of lake water were from $2.3{\times}7.7{\times}10^{5}\;cells/ml$. Total bacterial numbers in the sponges were $10^{3}-10^{4}$ times higher than those of lake water. In the genera Baikalospongia and Lubomirskia, the proportions of other unidentified bacterial groups to the Bacteria were 42.0-60.3% and 40.7-51.9%, respectively. These proportions were similar to those in lake water (22.6-46.3%). These results suggest that bacterial compositions in Lake Baikal water and sponges are highly unique.

• Korean Journal of Microbiology
• /
• v.45 no.2
• /
• pp.133-139
• /
• 2009

A nutrient-concentrating system was operated to retrieve total phosphorus efficiently from a non-point pollution source. Attached bacteria were expected to play an important role in the system. Phosphorous was concentrated by formation of bacterial biofilms on rubberized coconut fiber media of the system. While concentration of total phosphorus (TP) ranged merely 0.12~0.35 mg/L in the stream water, TP levels in pore water and the media were 0.45~0.86 mg/L and 40.91~242.71 mg/kg, respectively. Total bacterial number (TBN) ranged $0.3\sim2.3\times10^6$ cells/ml in stream water, $0.4\sim4.4\times10^6$ cells/ml in pore water and $0.8\sim1.9\times10^9$ cells/g in media. There was a close correlation between TP and TBN. Based on band profiles in DGGE analyses, bacterial communities in the media were different from that in the stream water. Clostridium spp. were abundant in the stream water while Aquabacterium spp. were dominant species in early stages of biofilm formation in the media. The genera predominant in matured biofilms of the media were Clostridium and Enterococcus.

• Korean Journal of Microbiology
• /
• v.37 no.2
• /
• pp.124-129
• /
• 2001

For elucidating the effect of salinity to the effect of wastewater treatment, the heterotrophic bacterial numbers, total bacterial numbers, and the bacterial community structure by FISH method were analyzed. The total bacterial numbers were not significantly changed by the salinity. But the heterotrophic bacterial numbers and bacterial community structures were drastically changed by the increase of salinity. In case of 1% salinity, the heterotrophic bacterial numbers and structure were slightly changed comparing to those of contol. In case of 2% and higher salinities, the numbers of heterotrophic bacteria and the proportions of Eubacteria, Proteobacteria $\alpha$-group, $\rho$-group and Cytophaga-Flavobacterium groups were deceasing. By these results, the salinity stress to bacterial community in waste water treatment was unveiled, and for sustaining the waste water treatment system, the salinity should be lower than 1%.

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