TABLE 4.
In vitro studies assessing the association between vitamin B-12 and the gut microbiome1
| First author, year (ref) | Comparison | Alpha-diversity | Beta-diversity | Bacteria abundance |
|---|---|---|---|---|
| Wang, 2019 (22) | Whey protein with CC or AC (AC + BL, CC + BL, AC + AL, CC + AL) vs. whey protein alone (AL, BL) | AC + BL and CC + BL higher than BL aloneAC + AL and CC + AL did not differ from AL alone | AL2 and CC + BL clustered from others | Bacteroidetes:Firmicutes ratio: not significantFamily2: CC + BL vs. BL higher Christensenellaceae, Prevotellaceae, Cariobacteriacese, Clostridiaceae, Chloroplast, Lactobacillaceae, Enterococcaceae, Staphylococcaeae; lower Bacteroidaceae, Eubacteriaceae, Rikenellaceae, Porphyromonadaceae, VerrucomicrobiaceaeFamily2: CC + AL vs. AL higher Enterococcaceae, Anearoplasmataceae, Bacteroidaceae; lower Peptostreptococcaceae, Prevotellaceae, Coriobacteriaceae, Clostridiaceae, Streptococcaceae, Mogibacteriaceae, EnterobacteriaceaeFamily2: AC + BL vs. BL higher Erysipelotrichaceae, Enterobacteriaceae; lower Lachnospiraceae, Bacteroidaceae, Eubacteriaceae, Rikensellaceae, Porphyromonadaceae, VerrucomibrobiaceaeFamily2: AC + AL vs. AL higher Leuconostocaceae; lower Peptostreptococcaceae, Christensenellaceae, Prevotellaceae, Coriobacteriaceae, Clostridiaceae, Streptococcaceae, Mogibacteriaceae, Enterobacteriaceae |
| CC vs. AC | CC had lower diversity compared with AC | Bacteroidetes:Firmicutes ratio: not significantFamily2: Higher Bacteroidiaceae,Eubacteriaceae; lower Bifidobacteriaceae,Flavinobacteriaceae,Peptostreptococcaceae,Lactobacillaceae,Ruminococcaceae | ||
| CC + AL vs. AC + AL | CC + AL had higher diversity compared to AC + AL | Bacteroidetes:Firmicutes ratio: not significantFamily2: Higher Christensenellaceae,Enterococcaceae,Lachnospiraceae,Anaeroplasmataceae,Bacteroidiaceae; lower Leuconostocaceae | ||
| CC + BL vs. AC + BL | Not significant | Bacteroidetes:Firmicutes ratio: not significantFamily2: Higher Prevotellaceae, Cariobacteriacese, Clostridiaceae,Chloroplast,Staphylococcaeae,Lactobacillaceae, Enterococcaceae,Lachnospiraceae; lower Enterobacteriaceae | ||
| Xu, 2018 (23) | CC vs. MC vs. control | CC vs. control: lower Shannon index (i.e., higher diversity), Chao1 not significantMC vs. CC and control: lower Chao1 (i.e., lower diversity) and lower Shannon index (i.e., higher diversity) | Control and CC groups clustered2Clustering by treatment and day, except MC samples on day 7 were more variable2 | Genus2: MC and CC increased Acinetobacter and decreased Bacteroides, Enterobacteriaceae unc, and Ruminococcaceae unc over timeGenus: MC was positively correlated with Pseudomonas bacteria in canonical correspondence analysisControl group differentially enriched with:-Order: Bifidobacteriales, Bacteroidales, Clostridiales-Family: Bifidobacteriaceae, Bacteroidaceae, Rikenellaceae, Lachnospiraceae, Ruminococcaceae, Sutterellaceae-Genus: Bifidobacterium, Bacteroides, Alistipes, Dorea, Eisenbergiella, Lachnospiraceae_unclassified, Ruminococcus2, Ruminococaccaceae unclassifiedCC differentially enriched with:-Order: Fusobacteriales, Caulobacterales-Family: Fusobacteriaceia,Caulobacteraceae-Genus:Clostridium cluster XIVb,Fusobacterium,Ruminococcus,BrevundimonasMC differentially enriched with:-Order: Pseudomonadales-Family: Clostridiacaeae1, Clostridiales family XI incertae sedis, Comamonadaceae, Moraxellaceae-Genus: Escherichia, Rhizobacter, Clostridium, Sedimentibacter, and Flavonifractor,Clostridium, Eubacteriaceae unclassified, Aceinetobacter, Moraxellaceae unclassified |
| Zheng, 2021 (24) | High- and low-CC supplement (CC-high, CC-low) and CC-enriched spinach (CCspinach-high, CCspinach-low) vs. control | CC-low and CCspinach-high clustered away from baseline and other groups (control, CC-high and CCspinach-low)2 | Genus2:CC-low vs. control: higher Klebsiella,Acinetobaacter; lower Comamonas,Bacteroides,Escherichia-ShigellaCC-high vs. control: higher Klebsiella; lower Bacteroides,Escherichia-ShigellaCC-high vs. CC-low: higher Comamonas, lower AcinetobacterCCspinach-low vs. control: higher Klebsiella and Bacteroides; lower ComamonasCCspinach-high vs. control: higher Acinetobacter; lower Comamonas, Klebsiella, Escherichia-Shigella, BacteroidesCCspinach-high vs. CCspinach-low: higher Acinetobacter; lower Klebsiella, Escheria-Shigella, Bacteroides | |
| Within-group changes | Alpha-diversity (Shannon, Simpson) decreased in CC-low, CC-high, and CCspinach-high group; increased for the CCspinach-low group; did not change in control group | Phylum:Control: no change in Proteobacteria, Firmicutes, BacteroidetesCC-low: Higher Proteobacteria, lower Firmicutes and BacteroidetesCC-high: Higher Proteobacteria, lower Firmicutes and BacteroidetesCCspinach-low: Lower Proteobacteria and higher BacteroidetesCCspinach-high: Higher Proteobacteria, lower Firmicutes Genus2:Control: higher Comamonas,Klebsiella; lower Escherichia-ShigellaCC-low: higher Acinetobacter; lower Escherichia-ShigellaCC-high: higher Comamonas,Klebsiella; lower Escherichia-Shigella,BacteroidesCCspinach-low: lower Escherichia-Shigella; higher BacteroidesCCspinach-high: higher Acinetobacter; lower Escherichia-Shigella,Bacteroides |
1
AC, adenosylcobalamin; AL, alpha-lactalbumin; B12, vitamin B-12; BL, beta-lactoglobulin; CC, cyanocobalamin; MC, methylcobalamin; ref, reference; unc, unclassified.
2
No statistical test reported, based on study authors or systematic review authors interpretation of figures.