Decreasing Pseudoflavonifractor capillosus

In Ian Lipkin et al 2017 study, high Pseudoflavonifractor capillosus was reported (on average). [Index to all posts on StudyWell, we have just 4 articles in total on PubMed. One of the articles cited that it was the bacteria formerly known as Bacteroides capillosus. With just one result

  • “Increased with proton pump inhibitors” [2016]

Relaxing the search criteria, we found 39 articles. “This genus [Pseudoflavonifractor] is one of the most prominent butyrate producers, providing energy to the colonic mucosa and known to regulate gene expression, inflammation, differentiation, and apoptosis in host cells (Luo et al., 2013).”

  • Phosphorus in diet increases [2016]
  • B. capillosus strongly stimulated rat mast cells to histamine secretion [2000] — so this may be a contributor to histamine issues with CFS. (see this post)


While usually not preferred, we do have some information on which ones may be effective:

  • Moxifloxacin — 67% of strains are resistant [2008]
  • ” Both faropenem and imipenem had MICs of < or=4 micro g/ml for all isolates of Bacteroides capillosus (10 isolates), ” [2002]
  • “All beta-lactamase-positive strains were found to be susceptible to imipenem and chloramphenicol….beta-Lactamase-positive Bacteroides strains showed 95% susceptibility to metronidazole and rifampicin; 90% susceptibility to piperacillin and cefoxitin; 85% susceptibility to tetracycline and erythromycin; 80% susceptibility to clindamycin and amoxycillin/clavulanic acid, and 76% susceptibility to ticarcillin.” [1999]
  • “Against beta-lactamase-producing strains of the Bacteroides fragilis group, B. capillosus, and Prevotella species all combinations of ceftriaxone and tazobactam showed enhanced in vitro activity and were eight- to 2048-fold more active than ceftriaxone alone.” [1994]
    • “All of the beta-lactamase-producing bacteroides strains were sensitive to a combination of amoxycillin with clavulanic acid (Augmentin).” [1990]
  • chlorofluoroquinolone, BAY y 3118.. All strains of Bacteroides capillosus, Prevotella spp., Porphyromonas spp., Fusobacterium spp., Clostridium spp., Eubacterium spp., Peptostreptococcus spp., and Veillonella parvula were susceptible” [1994]
  • Biapenem was also active against all of the B. capillosus, Prevotella, Clostridium, and Eubacterium strains and anaerobic cocci tested. Against all of the anaerobes tested, biapenem was 32- and 4-fold more active than clindamycin and metronidazole, respectively. ” [1994]
  • “Bacteroides capillosus) were resistant to penicillin, but none were resistant to clindamycin.” [1990]
  • “Bacteroides capillosus and Bacteroides ruminicola subsp. ruminicola) in the high sucrose diet (Diet-2000) group increased with time; those in the tetracycline group decreased with time.” [1989]  — reduce sugar intake
  • Azlocillin, mezlocillin, and cefoxitin had comparable activities, with resistance among members of the B. fragilis group and B. capillosus.” [1984]
  • Antibiotic resistance B. capillosus is resistant to benzylpenicillin (2 units), kanamycin (1mg) and neomycin (1mg) but sensitive to erythromycin and rifampicin  [Book 2014]

Herbs and Spices — nothing found 😦


Bacteria need food to grow. Other bacteria could be overproducing food that it needs.

  • Pseudoflavonifractor capillosus it is  class IV alcohol dehydrogenase [2016] from  ethanol [1994]

This lead me to:

  • ” Highest amounts of ethanol were produced by S. cerevisiae, L. fermentum, and W. confusa on glucose and by S. cerevisiae and W. confusa on fructose. Due to mannitol-dehydrogenase expressed in L. fermentum, ethanol production on fructose was significantly (P < 0.05) reduced. Pyruvate and citrate, two potential electron acceptors for regeneration of NAD+/NADP+, drastically reduced ethanol production with acetate produced instead in L. fermentum grown on glucose and W. confusa grown on glucose and fructose, respectively. In fecal slurries prepared from feces of four overweight volunteers, ethanol was found to be produced upon addition of fructose. Addition of A. caccae, L. acidophilus, L. fermentum, as well as citrate and pyruvate, respectively, abolished ethanol production.” [2016]

And thus speculative:

  • Reduce sucrose, glucose and fructose in your diet.
  • L. Fermentum probiotics (available)
  • Taking magnesium citrate or other citrate supplements. Ditto for pryuvate.

Bottom Line

Faecalibacterium and Pseudoflavonifractor are both butyrate producers. In CFS the Faecalibacterium is low and Pseudoflavonifractor is high. The only available treatment appears to be antibiotics. No herbs, spices, supplements or diet impact studies could be located. My own path would be to take the items above and intersect them with Cecile Jadin’s protocol — we have some items in common, such as:

  • Tetracyclines (my favorite in minocycline)
  • Augmentin
  • etc

THIS IS NOT MEDICAL ADVICE — this post is an education summary of what has been reported on PubMed. Always consult with a knowledgeable medical professional before changing diet, supplements and prescription drugs.

Clinical Studies Desired

In this very simple:

  • Ten patients in each group with uBiome done before. 2 weeks on one of the antibiotics suggested. 2 weeks later, another uBiome.
    • Hopeful outcome: which antibiotics have the best impact on Faecalibacterium and Pseudoflavonifractor.
      • Expected to find 1 in 5 being a double positive change.
  • Same as above, but taking Lactobacillus Fermentum for a month.