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Different types of beta-glucosidase enzymes have different optimal pH and temperatures. For example, beta-glucosidase produced from ''A. niger'' is optimal at a pH of 4.5 and a temperature of 58°C (136°F), whereas the enzyme for ''Brettanomyces anomalus'' is optimal at a pH of 5.75 and a temperature of 37°C (98°F) (it was active to some extent between 15°-55°C). The beta-glucosidase enzyme ceases effectiveness below a pH of 4.5 for one strain of ''B anomalus'' studied <ref name="Vervoort"></ref>.
See also:
* [http://www.cazy.org/Glycoside-Hydrolases.html Database of glycoside hydrolases.]
===Activity of ''Brettanomyces'' and ''Saccharomyces''===
The same strain of ''B. custersianus'' was screened for beta-glucosidase activity and aglycone byproducts during the refermentation of sour cherries in beer (a very small amount of the byproducts were manufactured by the yeast ''de novo'', particularly linalool, alpha-terpineol, alpha-ionol, and a precursor that leads to beta-damascenone under low pH conditions). Different portions of the cherries were tested: whole cherries with stones (pits), cherry pulp without stones, cherry juice without stones or other solids from the fruit, and the stones alone. Benzaldehyde (almond, cherry stone flavor) was produced during fermentation in all cases, and reduced to benzyl alcohol (almond flavor) and benzyl acetate (fruity, jasmine flavor) by the end of fermentation. There were higher levels of these benzyl based compounds in the whole cherries and cherry stone alone samples, indicating that cherry stones make a big impact on the almond flavors found in cherry sour beers. Methyl salicylate, linalool, alpha-terpineol (pine), geraniol (rose, lime, floral) and alpha-ionol (floral, violet), eugenol (spicy, clove, medicinal) and isoeugenol (fine delicate clove) levels increased in all forms of cherries added except for stones alone, indicating that these aglycones are more present in the flesh and juice of the cherries <ref name="Daenen2"></ref>. Another study that performed whole genome sequencing on a strain of ''B. naardenensis'' found that it had two genes that could potentially allow this species to produce beta-glucosidase, but this was not confirmed in the study <ref>[https://www.mdpi.com/2076-2607/7/11/489 Assembly and Analysis of the Genome Sequence of the Yeast Brettanomyces naardenensis CBS 7540. Ievgeniia A. Tiukova, Huifeng Jiang, Jacques Dainat, Marc P. Hoeppner, Henrik Lantz, Jure Piskur, Mats Sandgren, Jens Nielsen, Zhenglong Gu, and Volkmar Passoth. 2019. DOI: https://doi.org/10.3390/microorganisms7110489.]</ref>.
Wang et al. (2018) reported another type of glycosidic activity in one strain of ''B bruxellensis'' which is the conversion of the glycoside "mogroside V" into an artificial sweetener called siamenoside I. Other yeast and bacteria species were tested and did not find this particular glycosidic activity. [https://en.wikipedia.org/wiki/Mogroside Mogroside V] is found naturally in some fruit, specifically, an Asian fruit called [https://en.wikipedia.org/wiki/Siraitia_grosvenorii Lo Han Kuo (''Siraitia grosvenorii'')]. The artificial sweetener siamenoside is 563 times sweeter tasting than 5% sucrose. The specific enzyme responsible for this conversion that this strain of ''B. bruxellensis'' produced is called ''Db''Exg1 <ref>[https://www.sciencedirect.com/science/article/pii/S0308814618317473 Dekkera bruxellensis, a beer yeast that specifically bioconverts mogroside extracts into the intense natural sweetener siamenoside I. Reuben Wang, Yi-Chieh Chen, Yun-Ju Lai, Ting-Jang Lu, Shyue-Tsong Huang, Yi-Chen Lo. 2018. DOI: https://doi.org/10.1016/j.foodchem.2018.09.163.]</ref>.
See also :* [[Hops#Glycosides|Glycosides in Hops]].* [http://scottjanish.com/genetically-modified-gm-yeast-strains-unlocking-bound-hop-thiols-and-engineering-targeted-fermentation-characteristics/ "Genetically Modified (GM) Yeast Strains: Unlocking Bound Hop Thiols and Engineering Targeted Fermentation Characteristics," by Scott Janish.] ===Activity of Other Yeasts===A strain of ''Candida glabrata'' was selected in a study for its high beta-glucosidase activity, its tolerance to ethanol, and its ability to utilize maltose, and was shown to produce novel flavor characteristics in beer fermentation, including a significant increase in geraniol <ref>[https://www.sciencedirect.com/science/article/abs/pii/S0308814622026887#f0020 Application of non-Saccharomyces yeasts with high β-glucosidase activity to enhance terpene-related floral flavor in craft beer. Xiaoyu Han, Qiuxing Qin, Chenyu Li, Xiaoxuan Zhao, Fangxu Song, Mengjiao An, Ying Chen, Xiuqin Wang, Weidong Huang, Jicheng Zhan, Yilin You. 2022.]</ref>. Strains of ''Meyerozyma guilliermondii'' and ''Hanseniaspora uvarum'' that were isolated from a spontaneous wine fermentation have also been found to have positive results when co-fermented with ''S. cerevisiae'' in wine. Specifically, compared to the control wines, there were higher levels of the terpenes: isopulegol, citronellol, geranylacetone, geraniol, trans-nerolidol, and nerol. This was associated with the high beta-glucosidase activity of these yeast strains <ref>[https://www.frontiersin.org/articles/10.3389/fmicb.2022.845837/full Indigenous Non-Saccharomyces Yeasts With β-Glucosidase Activity in Sequential Fermentation With Saccharomyces cerevisiae: A Strategy to Improve the Volatile Composition and Sensory Characteristics of Wines. Gao Pingping, Peng Shuai, Sam Faisal Eudes, Zhu Yatong, Liang Lihong, Li Min, Wang Jing. 2022.]</ref>.
===Activity of Lactic Acid Bacteria===
http://onlinelibrary.wiley.com/doi/10.1111/j.1365-2672.2009.04461.x/full
https://ifst.onlinelibrary.wiley.com/doi/abs/10.1111/jfpp.16368
https://www.mdpi.com/2076-3921/11/2/305
===Cyanogenic Glycosides===
| Bitter Apricots with kernel (14-24 fruits for 1 kg; single kernel avg weight is 6 grams <ref name="calapricot"></ref>) || 25.2 - 43.2 (avg 1.8 mg per kernel <ref name="wiki_apric_kernel"></ref>) || Amygdalin <ref name="Gleadow_2014"></ref>
|-
| Elderflower (leaves/stems) || 1600 <ref name="nordicfoodlab">[https://web.archive.org/web/20190812014649/http://nordicfoodlab.org:80/blog/2013/10/elder-a-love-story "Elder – a love story". Justine de Valicourt. Nordic Food Lab. 10/03/2013. Retrieved 09/07/2016.]</ref> || Sambunigrin (or sometimes prunasin, holocalin, or zierin) <ref name="elderflowers">[https://www.researchgate.net/publication/233262135_Cyanogenic_Glycosides_from_Sambucus_Nigra Cyanogenic Glycosides from Sambucus Nigra. Marina Dellagreca, Antonio Fiorentino, Pietro Monaco, Lucio Previtera & Ana M. Simonet. 2006.]</ref>
|-
| Elderberries (fully ripe; under-ripe will contain more) || 30 <ref name="nordicfoodlab"></ref> || Sambunigrin (or sometimes prunasin, holocalin, or zierin) <ref name="elderflowers"></ref>
* [http://nordicfoodlab.org/blog/2013/10/elder-a-love-story "Elder: a love story", by Justine de Valicourt (cyanide in elderberries).]
* [http://www.dpi.nsw.gov.au/__data/assets/pdf_file/0013/111190/prussic-acid-poisoning-in-livestock.pdf Overview of HCN in various grass/straw/hay/livestock feed species.]
* [http://scottjanish.com/?s=glycosides Scott Janish blog articles about glycosides.]
==References==