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====UV Light====
There is some evidence that ''Brettanomyces'' can be sensitive to high levels of light. [https://www.frontiersin.org/articles/10.3389/fmicb.2021.747868/full Catrileo et al. (2021)] showed that under laboratory conditions, ''Brettanomyces bruxellensis'' was not able to grow when exposed to a 2500 lux and 4000 lux light source. For reference, the lux of indirect daylight is around 10,000 - 25,000 and the lux of office lighting is usually between 350 and 500 <ref>[https://en.wikipedia.org/wiki/Lux "Lux". Wikipedia. Retrieved 02/20/2022.]</ref>. However, when p-coumaric acid, a phenolic precursor that is present in plants and fruits (including malted barley and wheat), is present, certain genes are expressed during the growth of ''B. bruxellensis'' that allow it to adapt to the high light exposure conditions. While this study does not show at what level light begins to affect ''B. bruxellensis'' (the lowest light intensity that they tested was 2500 lux), [https://journals.asm.org/doi/abs/10.1128/jb.133.2.692-698.1978 Woodward et al. (1978)] demonstrated that ''Saccharomyces cerevisiae'' growth is unaffected by light until about 1,250 lux, at which point it begins to inhibit growth and the transfer of nutrients across the cell membrane <ref>[https://www.frontiersin.org/articles/10.3389/fmicb.2021.747868/full Catrileo D, Moreira S, Ganga MA and Godoy L (2021) Effect of Light and p-Coumaric Acid on the Growth and Expression of Genes Related to Oxidative Stress in Brettanomyces bruxellensis LAMAP2480. Front. Microbiol. 12:747868. doi: 10.3389/fmicb.2021.747868.]</ref><ref>[https://journals.asm.org/doi/abs/10.1128/jb.133.2.692-698.1978 J R Woodward, V P Cirillo, L N Edmunds, Jr. Light effects in yeast: inhibition by visible light of growth and transport in Saccharomyces cerevisiae grown at low temperatures. ASM Journals. Journal of Bacteriology. Vol. 133, No. 2. 1978. https://doi.org/10.1128/jb.133.2.692-698.1978.]</ref>. Grangeteau et al (2024) demonstrated that 10 minutes of ultra-high irradiance (UHI) blue light treatment resulted in the complete death of ''B. bruxellensis'' within a biofilm <ref>[https://www.sciencedirect.com/science/article/pii/S0023643824013215 C. Grangeteau, M. Lebleux, V. David, S. Rousseaux, H. Alexandre, L. Beney, S. Dupont. Ultra-high irradiance (UHI) blue light treatment: A promising method for inactivation of the wine spoilage yeast Brettanomyces bruxellensis. LWT, 2024, 117038. ISSN 0023-6438. https://doi.org/10.1016/j.lwt.2024.117038.]</ref>.
As a follow up question within Milk The Funk group on Facebook regarding if lower levels of light could impact ''Brettanomyces'' growth, Richard Preiss of Escarpment Labs performed an in-house experiment to grow ''Brettanomyces'' in the presence of standard fluorescent lights and reported finding no impact of the lights on ''Brettanomyces'' growth <ref>[https://www.facebook.com/groups/MilkTheFunk/posts/5523998620961640/?comment_id=558987711104045 Richard Preiss. Milk The Funk Facebook group post on impact of light on ''Brettanomyces'' growth. 03/07/2022.]</ref>.