TABLE 1.
In vitro studies assessing the association between vitamin B-12 and the gut microbiome1
| First author, year (ref) | In vitro model | Vitamin B12 intervention | Specimen | DNA extraction | Sequencing | Multiple comparison method |
|---|---|---|---|---|---|---|
| Wang, 2019 (22) | In vitro colon fermentation using stool samples from a 3-y-old and a rice starch–based nutritive medium | 8 groups receiving 0.5 uM/d of 1 of the following for 10 d: whey protein alone (BL, AL), B12 alone (AC, CC), or whey protein with B12 (AC + BL, CC + BL, AC + AL, CC + AL) | Fermentation broth (daily) | MicroElute Genomic DNA kit (Omega Inc.) | V3–V4 16S rRNA region, Illumina MiSeq | Duncan's multiple comparison test |
| Xu, 2018 (23) | In vitro colon fermentation using stool samples from 5 vitamin B-12–deficient patients and a corn starch–based nutritive medium | 3 groups receiving 1 of the following for 7 days: MC (1.25 mg/L), CC (1.25 mg/L), control (no supplementation) | Fermentation broth (day 4 and 7) | Genomic DNA kit (Qiagen) | V3–V4 16S rRNA region, Illumina MiSeq | Duncan's multiple comparison test |
| Zheng, 2021 (24) | In vitro colon fermentation using stool samples from 3 individuals aged 20–25 y and a nutritive medium (starch type not specified) | 5 groups receiving 1 of the following for 3 days: CC supplementation at a high or low dose, or CC-enriched spinach at a high (0.94 ug CC/g spinach) or low (0.78 μg CC/g spinach) dose, compared with control (no supplementation) | Fermentation broth (day 0 and 2) | Genomic DNA kit DP320 (Tiangen) | V3–V4 16S rRNA region, PCR | Duncan's multiple comparison test |
1AC, adenosylcobalamin; AL, alpha-lactalbumin; B12, vitamin B-12; BL, beta-lactoglobulin; CC, cyanocobalamin; MC, methylcobalamin; ref, reference; rRNA, ribosomal RNA; V, hypervariable region.