Lactobacillus Reuteri – BioGaia

After finding the last FDA report, I thought that a little more digging on the FDA site may be be beneficial to get some behind the scene information. What I found interesting was that it was engineered to be killed by all antibiotics. The “wild”/”original” strain was resistant to some.

I found the 2008 letter dealing with BioGaia’s straws and other uses. The full letter is 118 pages and covers everything you wanted to know about L. Reuteri (as of 2008). Some key points are:

  • Strain DSM 17938: aka  ATC 55730, SD 2112, ING 1 and MM 53 are alternative references.
  • “are substantially equivalent to their parent strain in all respects other than possession of these plasmids (which contain genes encoding for antibiotic resistance)… did not exhibit tetracycline resistance…, showing complete removal of lincomycin resistance” – in other words, they are less antibiotic resistance than that found in the human gut. Minocycline, doxycycline etc will kill this probiotic off.
  • “L reuteri in a drinking straw at the same level. 108 cfu ..The total estimated consumer exposure from these intended uses is less than 109 to 1010 cfu/day.” – 5 x109 cfu/day is what is reported to be needed to establish a probiotic — that is 50 drinking straws per day.
  • “Lactobacillus is a non-pathogenic genus ofLAB that consists of over 112 recognized species as of November 2007 (EFSA 2007).”
  • “L reuteri is the only Lactobacillus species reported to inhabit the gastrointestinal tract of all vertebrates and mammals. ranging from birds to humans (Casas and Dobrogosz 2000).L reuteri has been isolated in living form from every part of the digestive tract-the oral cavity. stomach. small intestine. and colon, as well as from stool samples and from the vagina (Reuter 2001).”
  • “Overall. 12% oft he mothers had detectable counts of L reuteri in their milk, with a higher rate of incidence in rural than urban areas”
  • “The ability of L reuteri to transit the harsh acidic conditions ofthe stomach (with fasting pH of about 1.5 and feeding pH between 3.0 and 5.0) successfully after oral ingestion (Wall et ale 2007) likely contributes to its ability to influence human physiology”
  • “Vandenplas et aI. (2007) observed that lactobacilli and other probiotics “do not colonize the gastro-intestinal tract as they become undetectable a few days after stopping the administration. “
  • “on animal and human studies of L. Reuteri, a number of animal studies and human clinical trials have established its value in lowering overall pathogen loads and controlling or eradicating infections of Salmonella typhimurium, Enterococcus faecaJis. Cryptosporidium parvum, Helicobacter pylori, and Streptococcus mutans, as well as other microorganisms such as Candida albicans and rotavirus (e.g., Kasravi et al. 1997, Edens et al. 1997, AIak et al. 1999, Balish and Warner 2002, Saggioroa et al. 2005).”
  • “L. reuteri, produce both L- and D-Iactate ” (50-50 split)
  • In the presence of glycerol, most strains of L reuteri produce reuterin (3- hydroxypropionaldebyde), a soluble broad-spectrum antimicrobial substance active in a wide range of pH values against Gram-positive and Gram-negative bacteria, especially E. coli, yeasts, fungi, protozoa, and viruses (Cleusix et al. 2007b). Reuterin production occurs during the anaerobic growth of L. reuteri in the presence of glycerol and low concentrations of glucose; it is not clear to what extent reuterin is produced in the human gut…. the production of reuterin was of the same magnitude for the 2 strains.”
  • NOTE: Some commercial strains do NOT produce reuterin

Addition Studies

Bottom Line

L. Reuteri should be taken with glycerol to encourage the production of reuterin (an antimicrobial). This strain has no natural resistance to antibiotics — that was intentionally removed. This suggests that it may not stand up well against dysfunctional bacteria that produces antibiotics/antimicrobials. If you take it, avoid taking it with any other probiotics.

“After a wash-out period of 14 days there was no evidence of either ATCC 55730 or DSM 17938 in the feces of any of the participants.” i.e. it failed to become established or was killed off by other bacteria.