Intestinal Flora

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Intestinal Flora


microorganisms inhabiting the intestine of healthy animals and man, generally without harm to the host.

The presence of microbes in the intestine is a symbiotic relationship that developed during the course of evolution. Microbes start to colonize the intestine within hours of the birth of the host, entering primarily with the food. The intestinal flora changes until the host reaches adulthood, when the flora becomes more or less stable. This normal intestinal flora consists of two groups of microorganisms: (1) commensal forms and saprophytes and (2) potentially pathogenic forms.

There are comparatively few microbes in the upper section of the small intestine, since most are destroyed in the stomach by the hydrochloric acid in the gastric juice. Aerobic streptococci (enterococci), lactobacilli, and yeasts are dominant in this section. In the lower sections of the intestine there are more gram-negative bacteria (primarily of Bacillus coli ) and spore-forming bacilli. A gram of feces contains 3–5 X 1011 microbes. There are about 1015 microorganisms in the total intestinal content. Disruption of the species composition and microbe ratios of the intestinal flora by, for example, antibiotics is called dysbacteriosis (dysbiosis). The progress of the digestive processes and the formation of a number of enzymes (for example, cellulase, which decomposes cellulose) and other physiologically active substances not synthesized by the host (certain amino acids, nucleo-tides, and vitamins) depend on the composition and condition of the intestinal flora.


References in periodicals archive ?
The intestinal flora of young pigs, with reference to early weaning, Escherichia coli and scours.
This suggests that breast milk may contribute to the establishment of the intestinal flora of infants.
On the other hand, the Turmeric Root Extract and Probiotics Healthy Intestinal Flora are under the LifeGlow brand—the company's official carrier for its health products.
The complex symbiotic relationship between the normal intestinal flora and the human host is beneficial to both.
coli and intestinal flora, pasted vents, and chick growth.
During critical illness with SIRS, the normal and appropriate balance of intestinal flora is not maintained, typified by a reduction in overall obligate commensals with a concomitant increase in potentially pathogenic bacterial species [13] that leads to a reduction in stool content of organic acids, such as butyrate, which are key fuels for mucosal cells as well as for stimulus of mucin production.
The intestinal tract is one of the more complex transformations during metamorphosis and diets change pre- and post-metamorphosis; therefore, it would be interesting to compare the results of adult intestinal flora to the intestinal flora of H chrysoscelis tadpoles.
Our use of inbred mice strains also enabled detailed analysis of the relationship between obesity traits, gene expression, intestinal flora, and diet.
Carbapenemases in Escherichia coli is a major concern, since these bacteria are widespread in the environment and in water and it is an important part of human intestinal flora.
2) Unfortunately, doses of doxycycline 50 mg or above have also been shown to increase antibiotic resistance and alter the normal intestinal flora.
Previously cited risk factors for intestinal toxemia botulism in adults include structural and functional gastrointestinal abnormalities, including Crohn disease (8), surgical alterations of the intestine (6,9), Meckel diverticulum (12,18), and modified intestinal flora caused by prolonged antimicrobial drug therapy (6-10,13).
During the development of FGIDs several post-inflammatory conditions manifest in altered intestinal flora or altered mucosa properties, which can possibly increase sensitivity to GI stimuli in healthy persons.