In vitro fermentation of sugar beet arabinan and arabino-oligosaccharides by the human gut microflora.
OBJECTIVE
To determine the fermentation profiles by human gut bacteria of arabino-oligosaccharides of varying degree of polymerization.


METHODS
Sugar beet arabinan was hydrolyzed with a commercial pectinase and eight fractions, of varying molecular weight, were isolated by gel-filtration chromatography. Hydrolysis fractions, arabinose, arabinan and fructo-oligosaccharides were fermented anaerobically by gut bacteria. Total bacteria, bifidobacteria, bacteroides, lactobacilli and the Clostridium perfringens/histolyticum sub. grp. were enumerated using fluorescent in situ hybridization.


RESULTS
Bifidobacteria were stimulated to different extents depending on molecular weight, i.e. maximum increase in bifidobacteria after 48 h was seen on the lower molecular weight fractions. Lactobacilli fluctuated depending on the initial inoculum levels. Bacteroides numbers varied according to fraction; arabinan, arabinose and higher oligosaccharides (degree of polymerization, dp > 8) resulted in significant increases at 24 h. Only carbohydrate mixtures with dp of 1-2 resulted in significant increases at 48 h (log 8.77 +/- 0.23). Clostridia decreased on all substrates.


CONCLUSIONS
Arabino-oligosaccharides can be considered as potential prebiotics.


CONCLUSIONS
Arabinan is widely available as it is a component of sugar beet pulp, a co-product from the sugar beet industry. Generation of prebiotic functionality from arabinan would represent significant added value to a renewable resource.
Al-Tamimi
M A H M
MA
School of Food Biosciences, The University of Reading, Whiteknights, Reading, UK.
Palframan
R J
RJ
Cooper
J M
JM
Gibson
G R
GR
Rastall
R A
RA
D001089:Arabinose / Q000378:metabolism; D001439:Bacteroides / Q000378:metabolism; D027461:Beta vulgaris / Q000378:metabolism*; D001644:Bifidobacterium / Q000378:metabolism; D002845:Chromatography / Q000379:methods; D003013:Clostridium / Q000378:metabolism; D015169:Colony Count, Microbial / Q000379:methods; D005232:Fatty Acids, Volatile / Q000096:biosynthesis; D005243:Feces / Q000382:microbiology; D005285:Fermentation; D041981:Gastrointestinal Tract / Q000382:microbiology*; D006801:Humans; D006868:Hydrolysis; D017404:In Situ Hybridization, Fluorescence / Q000379:methods; D007778:Lactobacillus / Q000378:metabolism; D008970:Molecular Weight; D009844:Oligosaccharides / Q000378:metabolism*; D011134:Polysaccharides / Q000378:metabolism*
D005232:Fatty Acids, Volatile; D009844:Oligosaccharides; D011134:Polysaccharides; C030080:araban; D001089:Arabinose