, 2008a). Sugar analysis was carried out by acid hydrolysis of polysaccharides, followed by reduction, acetylation and quantification of alditol acetates by gas–liquid chromatography, using methods adapted from Blakeney et al. (1983). Total uronic acids were determined colorimetrically at 580 nm from a standard curve of galacturonic acid using the method of Blumenkrantz & Asboe-Hansen (1973). Galacturonic acid and APO866 order glucuronic acid are not differentiated by this method. Determination of phenolics and flavonoids of NS and BS and solid residues recovered after in vitro gastric and duodenal digestion was carried out using a Shimadzu HPLC system equipped with a UV-Vis photodiode-array detector

and a fluorescence detector (Hewlett Packard 1046A). Detection was performed at 270 nm for hydroxybenzoic acids and flavanones and at 370 nm for flavonols. The UV spectra of the different compounds were recorded from 240 to 400 nm. The wavelengths used for fluorescence detection Thiazovivin of flavan-3-ols were: λex, 276 nm; λem, 316 nm. Data acquisition was performed using class-vp5 chemstation software (Shimadzu, Japan) as reported previously (Mandalari et al., 2009). Water-jacketed fermenter

vessels (300 mL) filled with 135 mL of presterilized basal growth medium (2 g L−1 peptone water, 2 g L−1 yeast extract, 0.1 g L−1 NaCl, 0.04 g L−1 K2HPO4, 0.04 g L−1 KH2PO4, 0.01 g L−1 MgSO4·7H2O, 0.01 g L−1 CaCl2·6H2O, 2 g L−1 NaHCO3, 2 mL Tween 80, 0.02 g L−1 haemin, 10 μL vitamin K1, Adenosine 0.5 g L−1 cysteine HCl, 0.5 g L−1 bile salts, pH 7.0) were inoculated with 15 mL of faecal slurry, prepared by homogenizing 10% w/v freshly voided faecal material of one healthy donor in 0.1 M phosphate-buffered saline (PBS), pH 7.0. The almond skin extract (NS or BS postdigestion) or fructo-oligosaccharides (FOS) was added to yield a final concentration

of 1% (w/v). A negative control was performed with no addition in the fermenter vessels. Each vessel was magnetically stirred, the temperature was set at 37 °C and pH was automatically maintained at 6.8. Anaerobic conditions were maintained by sparging the vessels with oxygen-free nitrogen at 15 mL min−1. Samples (5 mL) were removed at 0, 4, 8 and 24 h for bacterial enumeration and fatty acid analysis. Fermentations were run on three separate occasions. Bacteria were counted using FISH (Rycroft et al., 2001). Duplicate fermentation samples were diluted four times in 4% w/v filtered paraformaldehyde and fixed overnight at 4 °C. Samples were then washed twice with filtered PBS (0.1 M, pH 7.0) and stored at −20 °C in PBS/ethanol (1 : 1, v/v) until further analysis. Hybridization was performed at optimal temperature using genus-specific 16S rRNA-targeted oligonucleotide probes labelled with the fluorescent dye Cy3 for the different bacterial groups or with 4′,6-diamidino-2-phenylindole for total cell counts.