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==Wild ''Brettanomyces''==
''Brettanomyces'' is notoriously difficult to bioprospect from the wild. For example, a survey of wild yeasts in most of the US which isolated nearly 2,000 isolates with 262 unique species did not find a single occurrence of ''Brettanomyces'' in the wild (they only surveyed non-human inhabited wild areas of the US) <ref>[https://www.biorxiv.org/content/10.1101/2021.07.13.452236v1 Substrate, temperature, and geographical patterns among nearly 2,000 natural yeast isolatesWilliam J. Spurley, Kaitlin J. Fisher, Quinn K. Langdon, Kelly V. Buh, Martin Jarzyna, Max A. B. Haase, Kayla Sylvester, Ryan V. Moriarty, Daniel Rodriguez, Angela Sheddan, Sarah Wright, Lisa Sorlie, Amanda Beth Hulfachor, Dana A. Opulente, Chris Todd Hittinger. bioRxiv 2021.07.13.452236; doi: https://doi.org/10.1101/2021.07.13.452236.]</ref>. While it has been alleged by many that the natural environment for ''Brettanomyces'' is the skins of fruit or the bodies of insects, it wasn't until 2007 that science was able to show that ''Brettanomyces'' survives on the skins of grapes, although it does so in a very low population and a possibly [[Quality_Assurance#Viable_But_Nonculturable|"viable but not culturable"]] state. Renouf et al. (2007) and Comitini et al. (2019) demonstrated that an "enrichment ''Brettanomyces bruxellensis''" media called EBB is more efficient at first growing up ''Brettanomyces'' before trying to culture it on DBDM. ''Brettanomyces'' was allowed to grow for 80 days in the EBB media, and then streaked onto DBDM for selection for ''Brettanomyces'' (other wild yeast such as ''Hanseniaspora'' and ''Pichia'' grew much more readily than ''Brettanomyces'' that was cultured from wine grapes).
Using EBB, Comitini et al. (2019) found that after 80 days of incubation in the EBB medium, half of grapes samples from a vineyard with several varieties of grapes had wild ''Brettanomyces'' on their skins. The researchers also tested the air, the trailers, and the winery where the grapes were processed. They found no ''Brettanomyces'' in the air or the trailers, but did find a couple of valves that were used to transfer must have ''Brettanomyces''. Out of the four varieties of grapes sampled, Merlot grapes did not have any ''Brettanomyces'' growing on them, indicating that the variety of the grape might play a role in the ability of ''Brettanomyces'' to survive on grape skins. The researchers found a wide range of strains that matched the strains found in the winery, indicating that the ''Brettanomyces'' strains did originate from the grape skins <ref>[https://www.sciencedirect.com/science/article/pii/S0944501306000231?via%3Dihub Development of an enrichment medium to detect Dekkera/Brettanomyces bruxellensis, a spoilage wine yeast, on the surface of grape berries. Vincent Renouf, Aline Lonvaud-Funel. 2007. DOI: https://doi.org/10.1016/j.micres.2006.02.006.]</ref><ref>[https://www.frontiersin.org/articles/10.3389/fmicb.2019.00415/abstract Occurrence of Brettanomyces bruxellensis on grape berries and in related winemaking cellar. Francesca Comitini1, Lucia Oro, Laura Canonico, Valentina Marinelli, Maurizio Ciani. 2019. DOI: 10.3389/fmicb.2019.00415.]</ref>.