Chemopreventive effects from prebiotic inulin towards microbial 2-amino-1-methyl-6-phenylimidazo[4,5-b]pyridine bioactivation.
OBJECTIVE
Using a Simulator of the Human Intestinal Microbial Ecosystem (SHIME), we investigated the chemopreventive potential of prebiotic chicory inulin towards the in vitro bioactivation of 2-amino-1-methyl-6-phenylimidazo[4,5-b]pyridine (PhIP) by human intestinal microbiota.


RESULTS
HPLC data revealed that inulin significantly decreased the formation of the genotoxic PhIP-M1 metabolite, with the highest inhibitory activity in the colon ascendens (87% decrease). Interestingly, this chemopreventive effect correlated with alterations of bacterial community composition and metabolism in the different colon compartments. Conventional culture-based techniques and PCR-DGGE analysis on the SHIME colon suspension revealed significant bifidogenic effects during inulin treatment, whereas the overall microbial community kept relatively unchanged. Additionally, the production of short-chain fatty acids increased with 12%, 3% and 7%, while ammonia concentrations decreased with 3%, 4% and 3% in the ascending, transverse and descending colon compartments, respectively.


CONCLUSIONS
These results indicate that the prebiotic effects from inulin may also purport protective effects towards microbial PhIP bioactivation.


CONCLUSIONS
As the colonic microbiota may contribute significantly to the carcinogenic potential of PhIP, the search for dietary constituents that decrease the formation of this harmful metabolite, may help in preventing its risk towards human health.
Vanhaecke
L
L
Laboratory of Microbial Ecology and Technology (LabMET), Faculty of Bioscience Engineering, Ghent University - UGent, Coupure Links 653, Ghent, Belgium.
Grootaert
C
C
Verstraete
W
W
Van de Wiele
T
T
D001419:Bacteria / Q000235:genetics / Q000254:growth & development / Q000378:metabolism; D018651:Cichorium intybus / Q000737:chemistry; D003106:Colon / Q000378:metabolism / Q000382:microbiology; D015169:Colony Count, Microbial; D016172:DNA Fingerprinting; D005232:Fatty Acids, Volatile / Q000378:metabolism; D005285:Fermentation; D006801:Humans; D007093:Imidazoles / Q000378:metabolism*; D007444:Inulin / Q000494:pharmacology*; D009153:Mutagens / Q000378:metabolism*; D056692:Prebiotics; D011743:Pyrimidines / Q000378:metabolism
C530128:7-hydroxy-5-methyl-3-phenyl-6,7,8,9-tetrahydropyrido(3',2'-4,5)imidazo(1,2-a)pyrimidin-5-ium; D005232:Fatty Acids, Volatile; D007093:Imidazoles; D009153:Mutagens; D056692:Prebiotics; D011743:Pyrimidines; D007444:Inulin; C049584:2-amino-1-methyl-6-phenylimidazo(4,5-b)pyridine