Table 2.
Effects of apples and apple components on gut microbiota composition and activity.
| Type of Study | Duration-Diets-Daily Dose | Techniques Used | Results | Author |
|---|---|---|---|---|
| Animal (Wistar rats) | 6 weeks, 10 rats for each group: Control diet or 5% apple pomace (AP) 1B-juice colloids extract (54.3% soluble and 2.6% insoluble fiber) or 5% AP 4B-juice colloids extract, rich in soluble fiber (78.3% soluble and 1.8% insoluble) or 5% alcohol AP extract, rich in insoluble fiber (22.9% soluble and 73.3% insoluble) | FISH (caecal) Plate count (feaces) |
B-juice AP extracts:
Total SCFA, acetate and propionate: ↑, pH: ↓ Bacteroidaceae: ↑ (faeces) Alcohol AP extract: Total SCFA and butyrate: ↑, pH: ↓ Bacteroidaceae: ↑ (faeces) Eubacterium rectale: ↑ (caecal) |
Sembries et al. (2003) [24] |
| Animal (Wistar rats) | 4 weeks, 12 rats for each group: Control diet or Extraction juice from apple pomace | Plate count | Total SCFA and acetate: ↑, pH: ↓ Lactobacillus: ↑ , Bifidobacterium: ↑ Primary bile acids and neutral sterols: ↑ Secondary bile acids: ↓ |
Sembries et al., 2006 [25] |
| Animal (Fischer rats) | 4 weeks, 8 rats for each group: Control diet or 10 g apple or 7% apple pectin | qPCR |
Apple: Butyrate: ↑, pH: ↓, Bacteroides spp: ↓ Apple pectin: Butyrate:↑, pH: ↓, Bacteroides spp: ↓, Clostridium coccoides:↑ |
Licht et al., 2010 [26] |
| Animal ex vivo (mice) | Granny Smith apple fermented in vitro from faeces from diet induced lean (control) and obese mice. | qPCR | Firmicutes, Bacteroidetes, Enterococcus, Enterobacteriaceae, Escherichia coli and Bifidobacterium abundances from obese mice tended to be similar to lean mice after apple fermentation. | Condezo-Hoyos et al., 2014 [118] |
| Human | 2 weeks, 8 subjects: 2 apples | Plate count | Bifidobacteria: ↑ Clostridia: ↓, Enterobacteriaceae: ↓ |
Shinohara et al., 2010 [27] |
| Human Randomized, single blinded, controlled, crossover | 4 weeks, 23 subjects: Control: period of restricted diet or 550 g whole apples or 22 g apple pomace or 500 ml clear apple juice or 500 ml cloudy apple juice | qPCR | No changes in bacteria composition. pH: ↓ | Ravn-Haren et al., 2012 [15] |
↑: significant increase; ↓: significant decrease; SCFA: short chain fatty acids; FISH: fluorescence in situ hybridization; qPCR: quantitative polymerase chain reaction.