Editing Probiotic (section)

== Scientific guidelines for testing ==
First, probiotics must be alive when administered.<ref name="Fuller_1989" /><ref name="ReferenceA">{{Cite journal |last=Fuller |first=R |year=1991 |title=Probiotics in human medicine |journal=Gut |volume=32 |issue=4 |pages=439–442 |doi=10.1136/gut.32.4.439 |pmc=1379087 |pmid=1902810}}</ref><ref>Fuller R. ''Probiotics, the Scientific Thesis''. London: Chapman & Hall, 1992 {{ISBN?}}{{page needed|date=January 2024}}</ref> One of the concerns throughout the [[scientific literature]] resides in the viability and reproducibility on a large scale of observed results for specific studies, as well as the viability and stability during use and storage, and finally the ability to survive in stomach acids and then in the intestinal ecosystem.<ref name="bridging" />{{Failed verification|date=March 2023|reason=No mention of ability to survive stomach acids, nor of storage stability.}}

Second, probiotics must have undergone controlled evaluation to document ''health benefits'' in the target host. Only products that contain live organisms shown in reproducible human studies to confer a health benefit may claim to be probiotic.<ref name="bridging" /><ref name="pmid21637034">{{Cite journal |vauthors=Reid G, Gaudier E, Guarner F, Huffnagle GB, Macklaim JM, Munoz AM, Martini M, Ringel-Kulka T, Sartor B, Unal R, Verbeke K, Walter J |year=2010 |title=Responders and non-responders to probiotic interventions: how can we improve the odds? |journal=Gut Microbes |volume=1 |issue=3 |pages=200–204 |doi=10.4161/gmic.1.3.12013 |pmc=3023600 |pmid=21637034}}</ref><ref name="pmid16771855">{{Cite journal |vauthors=O'Hara AM, O'Regan P, Fanning A, O'Mahony C, Macsharry J, Lyons A, Bienenstock J, O'Mahony L, Shanahan F |year=2006 |title=Functional modulation of human intestinal epithelial cell responses by Bifidobacterium infantis and Lactobacillus salivarius |journal=Immunology |volume=118 |issue=2 |pages=202–215 |doi=10.1111/j.1365-2567.2006.02358.x |pmc=1782284 |pmid=16771855}}</ref> The correct definition of health benefit, backed with solid scientific evidence, is a strong element for the proper identification and assessment of the effect of a probiotic. This aspect is a challenge for scientific and industrial investigations because several difficulties arise, such as variability in the site for probiotic use (oral, vaginal, intestinal) and mode of application.<ref name="Fuller_1989" />

Third, the probiotic candidate must be a taxonomically defined microbe or combination of microbes ([[genus]], [[species]], and strain level). It is commonly admitted that most effects of probiotics are strain-specific and cannot be extended to other probiotics of the same genus or species.<ref name="ReferenceA" /> This calls for precise identification of the strain, i.e. [[genotypic]] and [[phenotypic]] characterization of the tested microorganism.<ref name="Rijkers_2010" />

Fourth, probiotics must be safe for their intended use. The 2002 FAO/WHO guidelines recommend that, though bacteria may be generally recognized as safe (GRAS), the safety of the potential probiotic be assessed by the ''minimum'' required tests:<ref>{{Cite journal |last1=Huys |first1=G |last2=Botteldoorn |first2=N |last3=Delvigne |first3=F |last4=Vuyst |first4=L. D. |last5=Heyndrickx |first5=M |last6=Pot |first6=B |last7=Dubois |first7=J. J. |last8=Daube |first8=G |year=2013 |title=Microbial characterization of probiotics – Advisory report of the Working Group "8651 Probiotics" of the Belgian Superior Health Council (SHC) |journal=Molecular Nutrition & Food Research |volume=57 |issue=8 |pages=1479–1504 |doi=10.1002/mnfr.201300065 |pmc=3910143 |pmid=23801655}}</ref>
* Assessment of certain metabolic activities (e.g. D-lactate production, bile salt deconjugation)
* Assessment of side effects in human studies
* Determination of antibiotic resistance patterns
* Epidemiological surveillance of adverse incidents in consumers (aftermarket)
* If the strain under evaluation belongs to a species known to produce toxins in mammals, it must be tested for toxin production. One possible scheme for testing toxin production has been recommended by the EU Scientific Committee on Animal Nutrition.<ref>{{Cite web |date=December 2001 |title=Commentary by the Scientific Committee on Animal Nutrition on Data Relating to Toxin Production |url=http://ec.europa.eu/food/fs/sc/scan/out73_en.pdf |url-status=live |archive-url=https://web.archive.org/web/20160629162223/http://ec.europa.eu/food/fs/sc/scan/out73_en.pdf |archive-date=29 June 2016 |access-date=5 June 2016 |website=Scientific Opinion |publisher=European Commission, Health & Consumer Protection Directorate-General |df=dmy-all}}</ref>
* If the strain under evaluation belongs to a species with known [[hemolytic]] potential, determination of hemolytic activity is required.

In Europe, EFSA adopted a premarket system for the safety assessment of microbial species used in food and feed productions to set priorities for the need for risk assessment. The assessment is made for certain microorganisms; if the result is favorable, it leads to "Qualified Presumption of Safety" <!-- (QPS) --> status.<ref>{{Cite journal |year=2007 |title=Introduction of a Qualified Presumption of Safety (QPS) approach for assessment of selected microorganisms referred to EFSA |journal=EFSA Journal |volume=587 |issue=12 |pages=1–16 |doi=10.2903/j.efsa.2007.587 |doi-access=free}}</ref>