Large Intestine Microbiota And Sampling Techniques Normal Microbiota

The large intestine including the cecum, colon, and the rectum harbors over 500 species of bacteria, mainly obligate anaerobes (99.9%) with 1011-1012CFU/g (2,10). Microorganisms isolated from large intestine and fecal samples are listed in Table 4. Bacteroides, Bifidobacteria, Eubacteria, Clostridia, and Enterobacteriaceae can predominantly be found in the colon. Novel molecular methods are aiding better understanding of the microbiota, which is challenging to culture due to the anaerobic nature of most of the microbiota, and insufficient knowledge of the culturing conditions (90,91). Knowledge about the mucosa-associated bacterial communities in different parts of the colon is limited as most attention has been focused on bacteria present in feces. Enormous microbial populations can develop in the lumen of the large bowel, and especially in that of the cecum because these areas have a relative stagnation in the flowing stream (up to 60 hours) and very low oxidation-reduction potentials. The transit time of the lumenal content exceeds the doubling times of bacteria. Whether the microbiota is transient or truly autochthonous to habitats in the region remains a main concern. Bacteria in food are known to pass into human feces at high population levels. Bacteria from habitats above the large bowel pass down into the lumen of that region. The population levels of transients probably do not contribute significantly to

Table 4 Microbiota Isolated from the Large Intestine and Feces by Culturing

Microbial types in large intestine

Microbial types in feces

Lactobacilli

Lactobacilli

Streptococci

Streptococci

Bifidobacteria

Bifidobacteria

Clostridia

Clostridia

Propionibacterium

Propionibacterium

Eubacterium

Eubacterium

Bacteroides

Bacteroides

Fusobacterium

Fusobacterium

Veillonella

Veillonella

Staphylococcus

Staphylococcus

Coliforms

Coliforms

Bacillus sp

Bacillus sp

Yeasts

Yeasts

Spiral shaped microbes

Spiral shaped bacteria

Actinobacillus

Peptococcus

Enterobacteriaceae

Ruminococcus

Enterococci

Coprococcus

Pregnancy And Childbirth

Pregnancy And Childbirth

If Pregnancy Is Something That Frightens You, It's Time To Convert Your Fear Into Joy. Ready To Give Birth To A Child? Is The New Status Hitting Your State Of Mind? Are You Still Scared To Undergo All The Pain That Your Best Friend Underwent Just A Few Days Back? Not Convinced With The Answers Given By The Experts?

Get My Free Ebook


Post a comment