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====Hop Biotransformation====
Colomer et al. (2020) was the first to examine the effects of ''Brettanomyces'' on hops during fermentation. The selected 4 strains of ''B. bruxellensis'' and 1 strain of ''B. anomalus'' that had the genetic markers for producing beta-glucosidase enzyme, and fermented them as a primary fermenter in a non-dry hopped beer, and also performed a second experiment where they inoculated the ''Brettanomyces'' strains in a dry hopped beer that was fermented out with ''S. cerevisiae''. Monoterpene alcohols were measured before and after inoculation with ''Brettanomyces''. In both beers, they found a decrease in geraniol and a rise in beta-citronellol. Beta-citranellol reached a level of 31.5 μg/L with one of the strains, which is a much higher level of beta-citronelol than anything that has been reported with ''S. cerevisiae''. See [https://onlinelibrary.wiley.com/doi/full/10.1002/jib.610 Figure 5] in the open access sstudy. Interestingly, the strains with the highest beta-glucosidase activity produced the lowest amount of beta-citranellol, indicating that there is not a link between beta-glucosidase activity in ''Brettanomyces'' and hop biotransformation. This might be due to the fact that most of the beta-glucosidase enzyme is produced within the cell and is not released outside of it <ref>[https://onlinelibrary.wiley.com/doi/full/10.1002/jib.610 Biotransformation of hop derived compounds by Brettanomyces yeast strains. Marc Serra Colomer, Birgitte Funch, Natalia Solodovnikova, Timothy John Hobley, Jochen Förster. 2020. DOI: https://doi.org/10.1002/jib.610.]</ref>.
For more information on glycosides, see the [[Glycosides]] page. For more infomration on hop biotransformation in general, see the [[Hops#Hop_Derived_Compounds_In_Beer_and_Biotransformations|Hops]] page.
===Nitrogen Metabolism===