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Beta-glycosidase enzymes can be added artificially, however there has been much interest in the natural capability of microorganisms to produce beta-glycosidases. There are two major categories of glucosidase activity: endogenous and exogenous. Endogenous enzymatic activity takes place inside of the cell, and exogenous enzymatic activity takes place outside of the cell. Microorganisms that show endogenous glucosidase activity have been shown not to be effective in alcoholic fermentation due to not tolerating low pH (optimum pH of 5), glucose, and ethanol. Generally, the flavorless glycosides remain unaffected by yeast fermentation, leaving them unused as a potential source for flavor and aroma <ref name="Winterhalter"></ref>.
Exogenous beta-glycosidase activity has been shown to be much more effective at releasing aglycones from glycosides. For glycosides which contain a glucose, which is the majority, beta-glucosidase cleaves the sugar, thus releasing the aglycone. For glycosides that contain disaccharides, usually another enzyme must be present to first break down the disaccharide before the beta-glucosidase can release the aglycone (beta-xylosidase, alpha-arabinosidase, alpha-rhamnosidase, or beta-apiosidase) <ref name="Winterhalter"></ref>. However, glycosides in tea leaves with more that contain disaccharide sugars have been observed to be broken down without the use of these other enzymes; the beta-glucosidase cleaves the aglycone from the disaccharide on it's its own. Yeast, bacteria, and fungi have been found to have both the beta-glucosidase and other enzymes needed for breaking down a wide range of glycosides to varying degrees <ref name="Maicas"></ref>.
===Secondary Metabolites===