Table 1.

Changes in the Intestinal Microbiome Associated With Alcohol in Rodent Models and Humans

Reference	Tested Organism	Experimental Condition	Methodology	Major Taxa Altered in Presence of Alcohol a,b	Major Finding
Yan et al. 2011	Mouse	3-week alcohol-fed mice/control isocaloric liquid	16S rRNA gene amplicon sequencing (pyro-sequencing) Mouse cecum	↑Verrucomicrobia phylum: ↑Akkermansia genus ↑Bacteroidetes phylum: ↑Bacteroidetes class, ↑Bacteroidales order, ↑Bacteroides genus, ↑Porphyromonadaceae family ↓Firmicutes phylum: ↓Lactococcus, ↓Pediococcus, ↓Lactobacillus, and ↓Leuconostoc genus	Alcohol-fed mice have GIT microbial community composition significantly altered from control mice indicating dysbiosis.
Mutlu et al. 2009	Rat	10-week alcohol-fed rats/control isocaloric dextrose	Length heterogeneity PCR (LH-PCR) Ileal and colonic rat mucosa tissue		Alcohol-fed rats have GIT microbial community composition significantly altered from control rats. Dysbiosis may be an important mechanism of alcohol-induced endotoxemia.
Mutlu et al. 2012	Human	Alcoholics with and without alcoholic liver disease/healthy patients	16S rRNA gene amplicon sequencing (pyro-sequencing) Mucosa sigmoid biopsies	↑Proteobacteria phylum: ↑Gammaproteobacteria class Firmicutes phylum: ↑Bacilli & ↓Clostridia class ↓Bacteroidetes phylum: ↓Bacteroidetes class Verrucomicrobia phylum: ↓Verrucomicrobiae class	Human chronic alcohol use is associated with changes in the mucosa-associated colonic bacterial composition in a subset of alcoholics from healthy controls. Dysbiotic microbial community alteration correlated with high level of serum endotoxin.
Chen et al. 2011	Human	Cirrhotic/healthy patients Alcoholic cirrhotic/healthy patients Hepititis B virus cirrhosis/alcoholic cirrhotic patients	16S rRNA gene amplicon sequencing (pyro-sequencing) Fecal samples	↑Proteobacteria phylum: ↑Gammaproteobacteria class: ↑Enterobacteriaceae family Firmicutes phylum: ↑Bacilli class: ↑Streptococcaceae family; Clostridia class: ↑Veillonellaceae and ↓Lachnospiraceae family ↑Fusobacteria phylum: ↑Fusobacteria class ↓Bacteroidetes phylum: ↓Bacteroidetes class *Bacteroidetes phylum: ↑Prevotellaceae family	Fecal GIT microbial community composition significantly altered in patients with cirrhosis compared with healthy individuals. *Prevotellaceae was enriched in alcoholic cirrhosis patients when compared with HBV cirrhosis patients and healthy controls.
Queipo-Ortuno et al. 2012	Human	Healthy patients 20-day intake of either red wine, de-alcoholized red wine, or gin	Quantitative real-time PCR Fecal samples	Red wine ↑Proteobacteria phylum: (↓Gin) ↑Fusobacteria phylum: (↑De-Alcoholized) (↓Gin) ↑Firmicutes phylum: (↓Gin) ↑Bacteroidetes phylum: (↓Gin) Red wine ↑Enterococcus genus (↑De-Alcoholized) (↓Gin) ↑Prevotella genus (↑De-Alcoholized) (↓Gin) ↑Bacteroides genus (↑De-Alcoholized) (↓Gin) ↑Bifidobacterium genus (↑De-Alcoholized) (↓Gin) ↑Bacteroides uniformis species: (↑De-Alcoholized) (↓Gin) ↑Eggerthella lenta species (↑De-alcoholized) (↓Gin) ↑Blautia coccoides-Eubacterium rectale species (↑De-alcoholized) (↓Gin) ↓Clostridium genus (↓De-Alcoholized) (↑Gin) ↓Clostridium histolyticum species (↓De-alcoholized) (↑Gin)	Red wine consumption, compared to de-alcoholized red wine and gin, significantly altered the growth of select GIT microbiota in healthy patients. This microbial community composition could influence the host’s metabolism. Also, polyphenol consumption suggests possible prebiotic benefits, due to the increase growth of Bifidobacterium.
Bode et al. 1984	Human	Alcoholic/hospitalized control patients	Aerobic and anaerobic bacterial culture incubation Jejunum aspirates	↑Gram-negative anaerobic bacteria ↑Endospore-forming rods ↑Coliform microorganisms	Chronic alcohol abuse leads to small intestinal bacterial overgrowth, suggesting dysbiosis may contribute to functional and morphological abnormalities in the GIT.

NOTES:

^aA comparison of bacterial Taxa either ↑, increased or ↓, decreased relative to the presence of alcohol.

^bTaxonomy was updated using the NCBI Taxonomy Browser.