Table 2.
Overview of in vitro and in vivo studies of AX and AXOS.
| Substrate (avDP-A/X) supplementation+ | Time | In vitro/In vivo | Significant concentration shift+ | Method microbial characterization+ | Significant bacterial shift+ | References | ||
|---|---|---|---|---|---|---|---|---|
| Butyrate | Propionate | Increase of | Decrease of | |||||
| AXOS (Nd-0.87) 13 g day−1 |
3 w | In vivo Humans | ↑ Most | ↑ | Nd | Nd | Nd | Gråsten et al., 2003 |
| AX (Nd-0.51) 10 g L−1 |
48 h | In vitro batch fermentation (human fecal inoculum) | ↑ | ↑ Most | 16S rRNA probe hybridization | Bacteroides-Prevotella-Porphyromonas spp. | ~ | Hopkins et al., 2003 |
| AX-66 kDa (Nd-0.40) AX-278 kDa (Nd-0.61) AX-354 kDa (Nd-0.61) 1% (m v−1) |
12 h | In vitro batch fermentation (human fecal inoculum) | ↑ Most Especially AX-66 kDa |
↑ | Fluorescent in situ hybridization (FISH) |
Bifidobacterium spp., Lactobacillus spp., and Bacteroides spp. Clostridium coccoides-Eubacterium rectale spp. (especially AX-66 kDa) |
~ | Hughes et al., 2007 |
| AXOS (61-0.58) (12-0.69) (15-0.27) (5-0.27) (3-0.26) 4% (m m−1) |
2 w | In vivo Rats | ↑ Only for AXOS (5-0.27) and (3-0.26) in colon |
~ | qPCR |
Bifidobacterium spp. [only for AXOS (5-0.27, 3-0.26) in cecum] |
~ | Van Craeyveld et al., 2008 |
| AXOS (15-0.27) 3 g L−1 |
3 w | In vitro SHIME® (human fecal inoculum) | ↓ In proximal colon vessel ↑ In transverse colon vessel |
↓ In proximal colon vessel ↑ Most in transverse colon vessel |
qPCR | ~ | Roseburia spp. (in proximal colon vessel) | Grootaert et al., 2009 |
| AXOS (29-0.30) 3 g L−1 |
3 w | In vitro SHIME® (human fecal inoculum) | ↑ Most In proximal, transverse, and distal colon vessels | ↑ In proximal and transverse colon vessels |
qPCR |
Bifidobacterium spp. and Bacteroides-Prevotella spp. (in proximal colon vessel) Lactobacillus spp. (in proximal and transverse colon vessels) Cl. coccoides-E. rectale spp. (in proximal and distal colon vessels) |
~ | Sanchez et al., 2009 |
| AXOS (6-0.26) 10 g day−1 |
3 w | In vivo Humans | Nd | Nd | qPCR | Bifidobacterium spp. and Bifidobacterium adolescentis (in some individuals) in feces | Lactobacillus spp. in feces | Cloetens et al., 2010 |
| AXOS (5-0.51) WU-AX (284-0.59) WE-AX (233-0.51) Combinations 5% (m m−1) |
2 w | In vivo Rats | ↑ Only for WU-AX, WU-AX + AXOS, and WU-AX + AXOS + WE-AX in cecum and colon |
~ | qPCR |
Bifidobacterium spp. (only for AXOS, WE-AX, WE-AX + AXOS, WU-AX + AXOS, WU-AX + AXOS + WE-AX in cecum and WE-AX, WE-AX + AXOS in colon) Lactobacillus spp. (only for WU-AX + AXOS in cecum) Roseburia-E. rectale spp. (WU-AX, WU-AX + AXOS, WE-AX + AXOS in cecum) |
Lactobacillus (for AXOS in cecum) | Damen et al., 2011 |
| AX (60-0.70) 10% (m m−1) |
4 w | In vivo Mice | Nd | Nd | qPCR | Bifidobacterium spp., Bacteroides-Prevotella spp., and Roseburia spp. in cecum | ~ | Neyrinck et al., 2011 |
| AX (60-0.70) 10% (m m−1) |
6 w | In vivo Rats | ↑ In cecum and feces |
↑ Most In cecum and feces |
High-resolution phylogenetic microarray (HITChip) | Eleven bacterial species (e.g., Bifidobacterium spp., Roseburia intestinalis, E. rectale, Collinsella spp., Clostridium colinum, Lachnospira pectinoschiza) in cecum Akkermansia muciniphila (in colon) |
Nine bacterial species (e.g., Ruminococcus bromii, Anaerostipes caccae, Eubacterium limosum, and A. muciniphila) in cecum | Van den Abbeele et al., 2011 |
| AXOS (Nd-Nd) 4.8 g day−1 |
3 w | In vivo Humans | ↓ | ~ | FISH | Bifidobacterium spp. in feces | ~ | Maki et al., 2012 |
| WB (74-0.61) (46-0.63) (42-0.92) (40-0.34) (4-0.22) PSH (300-0.29) (200-0.27) (88-0.16) (72-0.14) 1% (m v−1) |
48 h | In vitro batch fermentation (SHIME® human fecal inoculum) | ↑ Especially PSH (300-0.29), (200-0.27), (88-0.16) |
↑ Most Especially PSH (200-0.27), (88-0.16), (72-0.14) |
Nd | Nd | Nd | Pollet et al., 2012 |
| β-Endoxylanase-treated bread [containing AXOS (18-Nd)] Normal bread [containing AX (174-Nd)] 2.2 g day−1 |
3 w | In vivo Humans | ↑ In feces |
~ | FISH | Bifidobacterium spp. and Bacteroides-Prevotella spp. (for treated and normal bread) in feces Roseburia-E. rectale spp. and E. rectale-Cl. coccoides spp. (only for normal bread) in feces | Clostridium histolyticum- Clostridium perfringens | Walton et al., 2012 |
| AX (Nd-Nd) 10 g L−1 |
12 h | In vitro batch fermentation (human fecal inoculum) | ~ | ~ | Pyrosequencing | Bacteroides xylanisolvens | Blautia spp. | Yang et al., 2013 |
| AX (Nd-0.55) 17% (m m−1) |
3 w | In vivo Pigs | ↑ Most In cecum, proximal colon, transverse colon |
↑ In cecum, proximal colon, transverse colon |
qPCR | Bifidobacterium spp., Lactobacillus spp., F. prausnitzii, R. intestinalis, and Blautia coccoides–E. rectale spp. in feces | ~ | Nielsen et al., 2014 |
+
avDP, average degree of polymerization; A/X, arabinose/xylose ratio; Nd, not determined; ↑, increase of concentration; ↓, decrease of concentration; ~, no significant change; qPCR, quantitative PCR; WU-AX, water-unextractable AX; WE-AX, water-extractable AX; WB, AX and AXOS from wheat bran; PSH, AX and AXOS from Psyllium seed husk.