title: Glucosinolates Are Mainly Absorbed Intact in Germfree and Human Microbiota-Associated Mice.
abstract: Chemoprotective or genotoxic effects of glucosinolates occurring in Brassica vegetables are attributed to their hydrolysis products formed upon tissue damage by plant myrosinase. Since Brassica vegetables, in which myrosinase has been heat-inactivated, still display bioactivity, glucosinolate activation has been attributed to intestinal bacteria. The aim of this study was to investigate whether this is true. Glucoraphanin (172 mg/kg body weight) and neoglucobrassicin (297 mg/kg body weight) were administered intragastrically to germ free and human microbiota associated (HMA) mice. Approximately 30% of the applied doses of glucoraphanin and neoglucobrassicin were excreted unchanged in the urine of both germ free and HMA mice. Isothiocyanates, sulforaphane, and erucin, formed from glucoraphanin, were mainly excreted as urinary N-acetyl-l-cysteine conjugates. N-Methoxyindole-3-carbinol formed from neoglucobrassicin was observed in small amounts in both germ free and HMA mice. Formation of DNA adducts from neoglucobrassicin was also independent from bacterial colonization of the mice. Hence, intestinal bacteria are involved in the bioactivation of glucosinolates in the gut, but their contribution to glucosinolate transformation in HMA mice is apparently very small.
authors.affiliation: Department of Gastrointestinal Microbiology, German Institute of Human Nutrition Potsdam-Rehbruecke , Nuthetal, Germany.
authors.forename: Julia
authors.initials: J
authors.lastname: Budnowski
authors.affiliation: Department of Gastrointestinal Microbiology, German Institute of Human Nutrition Potsdam-Rehbruecke , Nuthetal, Germany.
authors.forename: Laura
authors.initials: L
authors.lastname: Hanske
authors.affiliation: Department of Nutritional Toxicology, German Institute of Human Nutrition Potsdam-Rehbruecke , Nuthetal, Germany.
authors.forename: Fabian
authors.initials: F
authors.lastname: Schumacher
authors.affiliation: Department of Nutritional Toxicology, German Institute of Human Nutrition Potsdam-Rehbruecke , Nuthetal, Germany.
authors.forename: Hansruedi
authors.initials: H
authors.lastname: Glatt
authors.affiliation: Institute of Food Chemistry, Hamburg School of Food Science, University of Hamburg , Hamburg, Germany.
authors.forename: Stefanie
authors.initials: S
authors.lastname: Platz
authors.affiliation: Institute of Food Chemistry, Hamburg School of Food Science, University of Hamburg , Hamburg, Germany.
authors.forename: Sascha
authors.initials: S
authors.lastname: Rohn
authors.affiliation: Department of Gastrointestinal Microbiology, German Institute of Human Nutrition Potsdam-Rehbruecke , Nuthetal, Germany.
authors.forename: Michael
authors.initials: M
authors.lastname: Blaut
mesh_terms: D000818:Animals; D001419:Bacteria / Q000378:metabolism*; D001711:Biotransformation; D001937:Brassica / Q000378:metabolism*; D005260:Female; D000069196:Gastrointestinal Microbiome; D005856:Germ-Free Life; D005961:Glucosinolates / Q000737:chemistry / Q000378:metabolism*; D006801:Humans; D007413:Intestinal Mucosa / Q000378:metabolism; D007422:Intestines / Q000382:microbiology*; D008297:Male; D051379:Mice; D008809:Mice, Inbred C3H
chemical_list: D005961:Glucosinolates
keywords: DNA adducts; bioactivation; glucosinolates; intestinal microbiota; isothiocyanates