Human Intestinal Microbial Ecosystem

Gmeiner M., Kniefel W., Kulbe K.D., Wouters R., De Boever P., Nollet L. and Verstreate V. (2000). Influence of a synbiotic mixture consisting of Lactobacillus acidophilus 74—2 and a frue loo I i go s acc h ari dc preparation on the microbial ecology sustained in a simulation of the human intestinal microbial ecosystem (SHIME reactor) . Appl Microbiol Biotechnol, 53, 219-223. 

The Netherlands SHIME, simulator of human intestinal microbial ecosystems of infants TMO, TNO gastrointestinal model. 

Bioacc., bioaccessible Ref, reference n.d. = not determined SBET, simple bioaccessibility extraction test RIVM, in vitro digestion model PBET, physiologically based extraction test SHIME, simulator of human intestinal microbial ecosystem TIM, TNO gastrointestinal model. 

Molly, K., Van de Woestyne, M., and Verstraete, W. (1993). Development of a 5-step multi-chamber reactor as a simulation of the human intestinal microbial ecosystem. Appl. Microbiol. Biotechnol. 

Eeckhaut E, Struijs K, Possemiers S, Vincken J-P, Keukeleire DD, Verstraete W. Metabolism of the lignan macromolecule into entero-lignairs in the gastrointestinal lumen as determined in the simulator of the human intestinal microbial ecosystem. / Agric Food Chem. 2008 56 4806-4812. 

MoUy, K., Van De Woestyne, M., De Smet, I. et al (1994) Validation of the simulator of the human intestinal microbial ecosystem (SHIME) reactor using microorganism-associated activities. Microb. Ecol Health Dis., 7,191-200. 

By now, it has not been made possible to determine the levels of antimicrobials that can cause an increase of primarily resistant Enterobacteriaceae in the gut of the consumer. As a result, measuring the microbial significance of antimicrobial residues continues to be the subject of considerable discussion. Much of the discussion involves the development of model systems that will reflect the effects of residue levels of antimicrobials on human intestinal microbial populations. The consensus of opinion at a recent symposium is that no such single system is available (64). The human intestine is a very complex microbial ecosystem, about which little is known of the effects of antimicrobial residues on the population dynamics and biochenoical responses (65). 

The evolution of human food consumption happened alongside the development of a vast bacterial ecosystem resident within the human body this gut microbiome comprises a cargo of commensals and symbionts that has collectively evolved to survive in the distal part of the human intestine. This community of microorganisms is thought to harbour more than 100-fold the number of genes within the human genome (BSckhed et al 2004). This genetic payload is carried by an excess of lO microbial cells with over 1000 bacterial types (Wallace et al 2011) - the evolution of which probably happened in response to the particular diet available to humans at a particular time. 

Colonic microbiota could now be considered as a microbial organ placed within a host organism. In addition to the obvious role of the intestine in the digestion and absorption of nutrients, the human G1 tract contains a huge collection of microorganisms. Microbiota has not been fully described, but it is clear that the human gut is home for an ecosystem of around 10 -10 " bacterial cells. As a whole, the microorganisms that live inside humans are estimated to outnumber human cells by a factor of ten. And the microbiome represents overall more than 100 times the human genome [78]. 

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