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Updated: Oct 5, 2025

Microbiota Analysis Using Two-step PCR and Next-generation 16S rRNA Gene Sequencing
Published on: October 15, 2019
Interplay between natural environment, human microbiota and immune system: A scoping review of interventions and
Christina Tischer1, Pirkka Kirjavainen2, Uwe Matterne3
1Institute of Clinical Epidemiology and Biometry, University of Wuerzburg, Josef-Schneider-Str. 2 / D7, 97080 Wuerzburg, Germany; State Institute of Health, Bavarian Health and Food Safety Authority, Prinzregentenstrasse 6, 97688 Bad Kissingen, Germany; Finish Institute for Health and Welfare, Environmental Health Unit, PO Box 95, FIN-70701 Kuopio, Finland.
Background:
Urbanization and biodiversity loss are linked to chronic disorders, in particular allergic diseases. The aim of this scoping review was to provide a synopsis of intervention studies specifically examining the influence of exposure to natural environments on human microbiota as well as immunological markers as suggested interlink between natural environment and the development of allergic diseases.
Methods:
We searched PubMed (MEDLINE®) and all references cited in the included studies following the PRISMA statement guidelines. No restrictions regarding age and sex of study participants, language or publication date were made. The protocol was registered at OSF REGISTRIES (https://osf.io/musgr).
Results:
After screening, eight intervention studies were included. The interventions reported were mainly of pilot character and various, ranging from nature-related educational programs, biodiversity interventions in day-cares to short-term contact with soil- and sand-preparations. Most of the studied interventions appeared to increase human microbiota richness and diversity in specific taxa groups in the short-time. Immunological markers were assessed in only two studies. In these, their associations with human microbiota richness were pre-dominantly reported.
Conclusion:
There is some evidence that the so-called biodiversity interventions have the potential to diversify human microbiota, at least over a short period. Adequately powered randomized controlled trials with long term follow-up are required to examine sustainable effects on microbiota and immune system.
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