- Rutin-induced beta-glucosidase activity in Streptococcus faecium VGH-1 and Streptococcus sp. strain FRP-17 isolated from human feces: formation of the mutagen, quercetin, from rutin. MacDonald, I.A., Bussard, R.G., Hutchison, D.M., Holdeman, L.V. Appl. Environ. Microbiol. (1984)