Biomaterial Database

Microbial hydrolysis of steviol glycosides. 2008

A G Renwick, and S M Tarka

School of Medicine, University of Southampton, UK.

A review of the role of gut microbiota in the metabolism of the steviol glycosides, stevioside and rebaudioside A, indicates that they are not absorbed intact but undergo hydrolysis by the intestinal microflora to steviol. Steviol is not metabolized by the intestinal flora and is absorbed from the intestine. The rate of hydrolysis for stevioside is greater than for rebaudioside A. Recent studies using mass spectrometry have shown that steviol-16,17-epoxide is not a microbial metabolite of steviol glycosides. Bacteroides species are primarily responsible for hydrolysis via their beta-glucosidase activity. Fecal incubation studies with both human and animal mixed flora provide similar results, and this indicates that the rat is an appropriate model for studies on steviol glycosides. Given the similarity in the microbial metabolism of stevioside and rebaudioside A with the formation of steviol as the single hydrolysis product that is absorbed from the intestinal tract, the toxicological data on stevioside are relevant to the risk assessment of rebaudioside A.

UI	MeSH Term	Description	Entries
D007422	Intestines	The section of the alimentary canal from the STOMACH to the ANAL CANAL. It includes the LARGE INTESTINE and SMALL INTESTINE.	Intestine
D004032	Diet	Regular course of eating and drinking adopted by a person or animal.	Diets
D005960	Glucosides	A GLYCOSIDE that is derived from GLUCOSE.	Glucoside
D006801	Humans	Members of the species Homo sapiens.	Homo sapiens,Man (Taxonomy),Human,Man, Modern,Modern Man
D006868	Hydrolysis	The process of cleaving a chemical compound by the addition of a molecule of water.
D000222	Adaptation, Physiological	The non-genetic biological changes of an organism in response to challenges in its ENVIRONMENT.	Adaptation, Physiologic,Adaptations, Physiologic,Adaptations, Physiological,Adaptive Plasticity,Phenotypic Plasticity,Physiological Adaptation,Physiologic Adaptation,Physiologic Adaptations,Physiological Adaptations,Plasticity, Adaptive,Plasticity, Phenotypic
D000818	Animals	Unicellular or multicellular, heterotrophic organisms, that have sensation and the power of voluntary movement. Under the older five kingdom paradigm, Animalia was one of the kingdoms. Under the modern three domain model, Animalia represents one of the many groups in the domain EUKARYOTA.	Animal,Metazoa,Animalia
D001419	Bacteria	One of the three domains of life (the others being Eukarya and ARCHAEA), also called Eubacteria. They are unicellular prokaryotic microorganisms which generally possess rigid cell walls, multiply by cell division, and exhibit three principal forms: round or coccal, rodlike or bacillary, and spiral or spirochetal. Bacteria can be classified by their response to OXYGEN: aerobic, anaerobic, or facultatively anaerobic; by the mode by which they obtain their energy: chemotrophy (via chemical reaction) or PHOTOTROPHY (via light reaction); for chemotrophs by their source of chemical energy: CHEMOLITHOTROPHY (from inorganic compounds) or chemoorganotrophy (from organic compounds); and by their source for CARBON; NITROGEN; etc.; HETEROTROPHY (from organic sources) or AUTOTROPHY (from CARBON DIOXIDE). They can also be classified by whether or not they stain (based on the structure of their CELL WALLS) with CRYSTAL VIOLET dye: gram-negative or gram-positive.	Eubacteria
D044602	Cellulases	A family of glycosidases that hydrolyse crystalline CELLULOSE into soluble sugar molecules. Within this family there are a variety of enzyme subtypes with differing substrate specificities that must work together to bring about complete cellulose hydrolysis. They are found in structures called CELLULOSOMES.	Laminarinase,Avicelase,Avicelase II,Cellulase Enzyme System,Cellulase Enzyme Systems,Endocellulase,Endocellulases,Endoglucanase I,Exo-cellulase,Exocellulase,Exocellulases,beta-Glucosidases,Enzyme System, Cellulase,Enzyme Systems, Cellulase,Exo cellulase,Systems, Cellulase Enzyme,beta Glucosidases
D045786	Diterpenes, Kaurane	A group of DITERPENES cyclized into four rings.	Ent-Kaurane,Ent-Kaurene,Kaurane,Kaurane Diterpenoid,Kaurane Diterpenoids,Ent-Kauranes,Ent-Kaurenes,Kauranes,Diterpenoid, Kaurane,Diterpenoids, Kaurane,Ent Kaurane,Ent Kaurene,Kaurane Diterpenes