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Bacterium

Bifidobacterium adolescentis

Common name: B. adolescentis

Beneficial Digestive Gut
Beneficial
Effect
Digestive
Impact
Gut
Location
Common
Prevalence
Last reviewed: April 4, 2025

Dominant adult-type bifidobacterium with exceptional metabolic versatility and gut-brain axis modulation

Prevalence: Present in 60-80% of healthy adults; peaks at ~5% relative abundance around age 40

Interacts with: Resistant starch degrader, GABA producer, Folate synthesizer, Acetate/lactate producer, Cross-feeder

Bifidobacterium adolescentis is the dominant adult-type bifidobacterium in the human gut microbiome, found in 60-80% of healthy adults[1]. Unlike infant-associated bifidobacteria, B. adolescentis specializes in plant-derived carbohydrates and exhibits remarkable genetic diversity that underlies its exceptional metabolic versatility, including resistant starch degradation, folate production, and GABA synthesis.

Characteristics and Prevalence

Scientifically accurate microscopy-style illustration of Bifidobacterium adolescentis showing its characteristic gram-positive Y-shaped or V-shaped bifurcated rod bacterium

B. adolescentis becomes the most abundant Bifidobacterium species by age 15, peaking at approximately 5% relative abundance around age 40[2]. Unlike other bifidobacteria that colonize breast-fed infants, B. adolescentis is more prevalent in formula-fed infants and becomes dominant after weaning.

Age-Related Patterns

  • Infants: Generally absent in breast-fed; present in formula-fed
  • Adults: 60-80% prevalence; cell density 10^9-10^10 cells/g feces
  • Elderly: Decreases with age but remains elevated in centenarians
  • Centenarians: 92% prevalence in semi-supercentenarians (105+) vs 80% in general elderly[3]

Genetic Diversity

Genomic analysis reveals exceptional strain variation with an open pan-genome of 16,696 genes, of which only 412 (2.47%) constitute the core genome[2]. Five major phylogenetic lineages exist with significant regional variation correlating with dietary patterns across Asia, Europe, and North America.

Metabolic Activities

Carbohydrate Utilization

B. adolescentis is specialized for plant-derived glycans rather than host-derived glycans, possessing higher CAZyme gene counts than common probiotic species[1].

Resistant Starch Degradation: B. adolescentis is the primary resistant starch (RS) degrader in the human gut. Strain P2P3 utilizes 63.3% of high-amylose corn starch granules through three cell-surface α-amylases with carbohydrate-binding modules (CBM25/26/74)[4]. This capability is strain-specific—some strains show 0% degradation.

SCFA Production and Cross-Feeding

B. adolescentis produces acetate and lactate in a 3:2 ratio via the bifid shunt pathway[5]. These metabolites support butyrate production through two cross-feeding mechanisms:

  1. End-product cross-feeding: Lactate converted to butyrate by Eubacterium hallii and Anaerostipes caccae (contributing 44-48% of butyrate carbon at pH 5.7)
  2. Substrate cross-feeding: Partial starch hydrolysis releases oligosaccharides for Roseburia species

This keystone function positions B. adolescentis as a primary degrader supporting butyrate-producing anaerobes essential for colonic health.

GABA Production

B. adolescentis is the primary GABA producer in the human gut, with the gadB gene present in >90% of strains[6]. High-producing strains achieve >250 mM GABA through glutamate decarboxylation via the GAD system (gadB/gadC).

GABA expression is detected in 15-20% of healthy subjects' gut metagenomes, positioning B. adolescentis as a potential psychobiotic for gut-brain axis modulation. Clinical evidence shows strain SBT2786 improves sleep quality in high-stress individuals (p < 0.05 for PSQI-J, ESS, and mood scores)[7].

Folate Production

B. adolescentis is a folate-prototrophic species capable of de novo vitamin B9 synthesis. Adult-derived strains produce significantly more folate than infant-derived strains[8]:

Strain Origin Folate Production
Adult-derived 580-935 μg/g dry matter
Infant-derived 35-200 μg/g dry matter

The predominantly produced form is 5-methyl-tetrahydrofolate (5-MTHF), the bioactive form. Strain MB 239 shows particularly stable production across pH, carbon sources, and external folate levels.

In fecal cultures, supplementation with B. adolescentis MB 239 increased folate from 28.3 to 52.8 ng/mL, potentially reducing localized colonic folate deficiency and colorectal cancer risk.

Immunomodulatory Effects

Treg Induction and Anti-Inflammatory Activity

B. adolescentis demonstrates potent immunomodulatory effects through regulatory T cell induction[9]:

  • Treg/CD4 T cells: Increased from 34.8% to 45.6% (p < 0.05)
  • Anti-inflammatory cytokines: Elevated IL-10, IL-4, IL-5
  • Pro-inflammatory cytokines: Decreased TNF-α, IL-6, IL-1β, IL-18

The mechanism involves H3K9 histone acetylation at the Il10 promoter via TLR2-ERK/p38 MAPK signaling[10]. Notably, strain IF1-03 induces Tregs while strain IF1-11 induces Th17, demonstrating critical strain-specificity.

Gut Barrier Enhancement

B. adolescentis strengthens intestinal barrier function by:

  • Upregulating tight junction proteins (Occludin, ZO-1, Claudin-1)
  • Increasing mucin production (Muc2, Muc3)
  • Reducing LPS penetration
  • Preventing TNF-α-induced barrier disruption

Health and Disease Associations

Inflammatory Bowel Disease

B. adolescentis is significantly reduced in IBD patients. Supplementation with strain ATCC15703 ameliorates chronic colitis in DSS mouse models[9]:

  • Reduced diarrhea scores (p < 0.05)
  • Lower spleen weight (p < 0.001)
  • Increased Th2/CD4 T cells: 4.32% vs 2.28% (p < 0.001)
  • Improved Bacteroidetes:Firmicutes ratio: 5 → 17

Irritable Bowel Syndrome

Clinical trial with strain PRL2019 in pediatric IBS demonstrated[11]:

  • Complete remission: 52.8% vs 19.4% placebo (p = 0.003)
  • IBS-SSS improvement: p = 0.001
  • Stool normalization: 25% → 58.3% (p = 0.004)

Colorectal Cancer Protection

B. adolescentis is significantly depleted in CRC patients. Supplementation suppresses tumorigenesis by inducing CD143+ cancer-associated fibroblasts (CAFs) via Wnt/β-catenin/GAS1 signaling[12].

Cell-free supernatants inhibit CRC organoid growth:

  • 15.51% reduction in organoid perimeter
  • 39.67% reduction in volume (p < 0.0001)

The mechanism involves butyric acid upregulating CYP1A1 and acting as an HDAC inhibitor.

Metabolic Health and Obesity

Resistant starch-induced enrichment of B. adolescentis mediates significant metabolic benefits[13]:

  • Weight loss: -2.81 kg (95% CI: -3.55 to -2.07, p < 0.001)
  • Insulin sensitivity: Median +1.05 mg/kg/min GIR (p = 0.025)
  • Inflammation: Reduced TNFα (p = 0.014) and IL-1β (p = 0.046)

For Type 2 Diabetes, B. adolescentis strains are more effective than B. bifidum, significantly decreasing glucose AUC and improving HOMA-IR[14].

Longevity Association

Higher B. adolescentis abundance correlates with healthy aging and longevity. Centenarian populations consistently show maintained or elevated levels compared to general elderly populations[3], suggesting it as a biological marker for healthy aging.

Probiotic Potential

Clinical Applications

Condition Strain Dose Duration Outcome
Pediatric IBS PRL2019 20×10^9 CFU/day 12 weeks 52.8% complete remission
Sleep/Stress SBT2786 >1.0×10^11 cells/day 4 weeks Improved sleep, mood
Obesity RS-enriched 40g RS2/day 8 weeks -2.81 kg weight loss

Prebiotic Synergies

B. adolescentis demonstrates strong synergy with prebiotics, particularly resistant starch type 2 from high-amylose maize, which specifically enriches this species and mediates metabolic benefits[13].

Other supportive prebiotics include:

  • Fructo-oligosaccharides (FOS)
  • Galacto-oligosaccharides (GOS)
  • Inulin
  • Arabinoxylan oligosaccharides

Strain-Specific Considerations

Metabolic capabilities vary dramatically between strains[2]:

Trait Prevalence Range
Folate production 100% 23-281 ng/mL
Lactose metabolism 100% 2-232 Miller units β-gal
GABA production 80% 0.3-14.4 mM
Resistant starch utilization 66% 26-74%
Fecal gas reduction 100% 25-79% (mean 62%)

This strain diversity necessitates careful strain selection for specific therapeutic applications.

B. adolescentis Within the Bifidobacterium Genus

Bifidobacterium adolescentis belongs to the Bifidobacterium genus, one of the most important groups of beneficial bacteria in the human gut microbiome. Understanding its relationship to other Bifidobacterium species helps clarify its unique role.

The Bifidobacterium Family

The Bifidobacterium genus contains over 80 recognized species, with several playing key roles in human health at different life stages:

  • B. longum (view profile/): The most broadly distributed species across the lifespan; specializes in immune modulation and gut-brain axis effects. While B. longum includes infant-associated subspecies (B. longum subsp. infantis), B. adolescentis is strictly an adult-type species
  • B. bifidum (view profile/): Specializes in host-derived glycan degradation (mucins, HMOs); more focused on immune function than metabolic versatility
  • B. breve: Primarily an infant-associated species that declines after weaning, as B. adolescentis rises to dominance
  • B. animalis subsp. lactis: Common in commercial probiotics (e.g., BB-12); well-studied but lacks the metabolic versatility of B. adolescentis

What Distinguishes B. adolescentis

Compared to other Bifidobacterium species, B. adolescentis is uniquely characterized by:

  • Plant glycan specialization: While B. bifidum degrades host mucins and B. longum subsp. infantis targets HMOs, B. adolescentis is the primary plant-derived carbohydrate specialist
  • Resistant starch degradation: A capability rare among other Bifidobacterium species
  • GABA production: The highest GABA-producing capacity of any Bifidobacterium species
  • Folate output: Among the highest folate producers in the genus
  • Adult dominance: Becomes the most abundant Bifidobacterium in adults by age 15

Bifidobacterium as Probiotic Supplements

The Bifidobacterium genus is one of the most widely used groups in probiotic supplements, and B. adolescentis is emerging as a particularly promising species for adult probiotic applications.

Current Probiotic Landscape

Most commercial probiotic supplements contain B. animalis subsp. lactis or B. longum rather than B. adolescentis. However, clinical evidence is increasingly supporting B. adolescentis-specific strains:

Strain Application Key Evidence
PRL2019 Pediatric IBS 53% complete remission vs 19% placebo in RCT
iVS-1 Lactose intolerance 71% pain reduction, 88% diarrhea reduction
SBT2786 Sleep/stress Improved sleep quality and mood in high-stress adults

Selecting a Bifidobacterium Probiotic

When considering Bifidobacterium probiotic supplements:

  • Strain matters: Effects are highly strain-specific within B. adolescentis (e.g., IF1-03 induces anti-inflammatory Tregs while IF1-11 induces pro-inflammatory Th17)
  • Dose considerations: Clinical trials have used doses ranging from 1x10^9 to 2x10^10 CFU/day
  • Synbiotic approach: Pairing B. adolescentis with resistant starch may enhance colonization and metabolic benefits
  • Multi-species formulations: Combining B. adolescentis with complementary species like B. longum may provide broader benefits

For a comprehensive overview of probiotic bacteria and their applications, see our guide to probiotics.

Conclusion

Bifidobacterium adolescentis represents a metabolically versatile keystone species of the adult gut microbiome with exceptional probiotic potential. Its unique capabilities in resistant starch degradation, folate and GABA production, and cross-feeding relationships position it as central to gut ecosystem function. Clinical evidence supports its use for IBS, metabolic disorders, and potentially colorectal cancer prevention. The strong association with healthy aging and longevity further highlights its importance in maintaining lifelong gut health.

Documented Strains

PRL2019

Bifidobacterium adolescentis PRL2019

Moderate research
Pediatric IBS symptom remissionGut-brain axis modulation via GABAStool normalization in IBS

Key Findings

↑

Pediatric IBS

More than twice as many children achieved complete remission vs placebo (53% vs 19%)

↑

Stool normalization in IBS

Normal stool pattern more than doubled — from 1 in 4 to over half of children by week 12

The first and only Bifidobacterium adolescentis strain tested in a multicentric, double-blind, placebo-controlled RCT for IBS — demonstrating a 2.7-fold higher complete remission rate versus placebo in children, and uniquely identified as the highest GABA-producing B. adolescentis strain among 82 screened isolates, connecting gut microbiome GABA output directly to IBS visceral hypersensitivity

iVS-1

Bifidobacterium adolescentis iVS-1

Limited research
Lactose intolerance symptom reliefGut permeability improvement

Key Findings

↑

Lactose intolerance symptoms

Abdominal pain fell 71%, diarrhea fell 88%, bloating fell 53% vs placebo

↑

Gut symptoms overall

All major gut symptoms significantly improved within 2 weeks, effect persisted at washout

The first B. adolescentis strain selected specifically for high β-galactosidase activity via in vivo competition on galactooligosaccharides — and the only B. adolescentis strain with a published human RCT demonstrating significant reduction across all major lactose intolerance symptoms including abdominal pain (−71%), diarrhea (−88%), and bloating (−53%)

IM38

Bifidobacterium adolescentis IM38

Preclinical research
HFD-induced colitisObesity-associated inflammationNF-kB inhibitionGut barrier protection

Key Findings

↑

Obesity-associated colitis

Inhibited HFD-induced fat gain, downregulated NF-kB and TNF-alpha, increased Tregs (preclinical)

IM38 has a dual mechanism of action targeting both adipogenesis and obesity-associated intestinal inflammation — simultaneously inhibiting NF-kB activation and reducing LPS production by reshaping the microbiota; one of very few B. adolescentis strains with in vivo anti-colitis data

SPM2022

Bifidobacterium adolescentis SPM2022

Preclinical research
Anti-obesityLipid metabolismAdipogenesis inhibition

Key Findings

↑

Obesity (preclinical)

72% reduction in weight gain and 60% reduction in mesenteric fat in HFD mice

Very recently isolated Korean strain (2022) with high-magnitude preclinical anti-obesity effects; 72% reduction in weight gain relative to HFD control in mice — unusually strong preclinical effect size requiring human validation

Associated Conditions

→ Anxiety → Depression → Type 2 Diabetes → Obesity → Colorectal Cancer

Related Organisms

B
Bifidobacterium animalis subsp. lactis Digestive
B
Bifidobacterium animalis subsp. lactis Digestive
B
Bifidobacterium bifidum Digestive
B
Bifidobacterium breve Immune
B
Bifidobacterium lactis Immune
B
Bifidobacterium longum Immune

Frequently Asked Questions

What is Bifidobacterium adolescentis?

Bifidobacterium adolescentis is a bacterium found in the human microbiome.

Where is Bifidobacterium adolescentis found in the body?

Bifidobacterium adolescentis is primarily found in the Gut.

What are the health impacts of Bifidobacterium adolescentis?

Bifidobacterium adolescentis primarily impacts Digestive and is beneficial for human health.

Research References

  1. Duranti S, et al.. Genomic characterization and transcriptional studies of Bifidobacterium adolescentis. Scientific Reports. 2016. doi:10.1038/srep23971 ↩
  2. Van Haute M, et al.. Strain-level diversity and functional variation of Bifidobacterium adolescentis. mSphere. 2025. doi:10.1128/msphere.00673-25 ↩
  3. Ku S, et al.. Bifidobacterium adolescentis and healthy aging. Food Science and Biotechnology. 2024. doi:10.1007/s10068-024-01631-y ↩
  4. Jung DH, Kim GY, Kim IY, et al.. Bifidobacterium adolescentis P2P3 degrades resistant starch granules through three cell-surface α-amylases. International Journal of Biological Macromolecules. 2023. doi:10.1016/j.ijbiomac.2023.124062 ↩
  5. Belenguer A, et al.. Two routes of metabolic cross-feeding between Bifidobacterium adolescentis and butyrate-producing anaerobes. Applied and Environmental Microbiology. 2006. doi:10.1128/AEM.72.5.3593-3599.2006 ↩
  6. Duranti S, et al.. Bifidobacterium adolescentis is a primary GABA producer in the human gut. The ISME Journal. 2021. doi:10.1038/s41598-020-70986-z ↩
  7. Murakami S, Kurihara C, Tanaka Y, et al.. Bifidobacterium adolescentis SBT2786 improves sleep quality in healthy adults with high stress levels. Journal of Functional Foods. 2024. doi:10.1016/j.jff.2024.106078 ↩
  8. Pompei A, et al.. Folate production by bifidobacteria as a potential probiotic property. Applied and Environmental Microbiology. 2007. doi:10.1128/AEM.01763-06 ↩
  9. Fan L, et al.. B. adolescentis ameliorates chronic colitis by regulating Treg/Th2 response and gut microbiota remodeling. Gut Microbes. 2021. doi:10.1080/19490976.2020.1826746 ↩
  10. Yu R, et al.. Strain-specific effects of B. adolescentis on Treg/Th17 balance via TLR2-ERK/p38 MAPK signaling. Nutrients. 2019. doi:10.3390/nu11040782 ↩
  11. Giorgio R, Pensabene L, Romano C, et al.. Bifidobacterium adolescentis PRL2019 for pediatric irritable bowel syndrome: a multicentric randomized double-blind placebo-controlled trial. Microorganisms. 2025. doi:10.3390/microorganisms13030627 ↩
  12. Chen D, et al.. B. adolescentis supplementation suppresses colorectal cancer by inducing CD143+ CAFs. Cancer Communications. 2023. doi:10.1002/cac2.12469 ↩
  13. Li X, et al.. Gut microbiome and serum metabolome alterations associated with isolated systolic hypertension. Nature Metabolism. 2024. doi:10.1038/s42255-024-00988-y ↩
  14. Qian Y, et al.. A comparison of B. adolescentis and B. bifidum in relieving Type 2 diabetes. Nutrients. 2022. doi:10.3390/nu14122479 ↩