In vitro digestion of sinigrin and glucotropaeolin by single strains of Bifidobacterium and identification of the digestive products

• Published in: Food and chemical toxicology 2004-03, Vol.42 (3), p.351-357
• Main Authors: Cheng, D.-L., Hashimoto, K., Uda, Y.
• Format: Article
• Language: English
• Subjects: 3-butenenitrile; Acetonitriles - analysis; Acetonitriles - metabolism; allyl isothiocyanate; anticarcinogenic activity; ascorbic acid; Ascorbic Acid - pharmacology; benzyl isothiocyanate; Bifidobacterium; Bifidobacterium - classification; Bifidobacterium - metabolism; Bifidobacterium adolescentis; Bifidobacterium longum; Bifidobacterium pseudocatenulatum; Bifidobacterium sp; biodegradation; Biological and medical sciences; Biotransformation; Brassicaceae; Carcinogenesis, carcinogens and anticarcinogens; chemical constituents of plants; culture media; Culture Media, Conditioned - chemistry; Digestive System - metabolism; Digestive System - microbiology; food composition; Foods and miscellaneous; Gas Chromatography-Mass Spectrometry; gastrointestinal system; Glucosinolate; glucosinolates; Glucosinolates - metabolism; glucotropaeolin; humans; Hydroxamic Acids - metabolism; in vitro digestion; intestinal microorganisms; Isothiocyanate; isothiocyanates; Isothiocyanates - analysis; Isothiocyanates - metabolism; Medical sciences; Nitrile; nitriles; Nitriles - analysis; Nitriles - metabolism; nutrient availability; phenylacetonitrile; protective effect; sinigrin; Thioglucosides - metabolism; Tumors; vegetable extracts
• ISSN: 0278-6915; 1873-6351
• DOI: 10.1016/j.fct.2003.09.008

Three strains of Bifidobacterium sp., B. pseudocatenulatum, B. adolescentis, and B. longum were studied for their ability to digest glucosinolates, sinigrin (SNG) and glucotropaeolin (GTL), in vitro. All strains digested both glucosinolates during 24–48 h cultivation, accompanied by a decline in the medium pH from 7.1 to 5.2. The digestion of glucosinolates by a cell-free extract prepared from sonicated cells of B. adolescentis, but not cultivated broth, increased in the presence of 0.5 mM l-ascorbic acid. Also, a time-dependent formation of allyl isothiocyanate (AITC) was observed when the cell-free extract was incubated with 0.25 mM SNG for 120 min at pH 7.0. These reaction features suggest that the digestive activity may have been due to an enzyme similar to myrosinase, an enzyme of plant origin. GC–MS analysis of the Bifidobacterial cultured broth showed that the major products were 3-butenenitrile (BCN) and phenylacetonitrile (PhACN), from SNG and GTL, respectively and nitriles, probably due to a decrease in the pH of the media. AITC and benzyl isothiocyanate (BzITC) were barely detectable in the broth. It was concluded that the three species of Bifidobacteria could be involved in digestive degradation of glucosinolates in the human intestinal tract.