Isolation and identification of Enterococcus gallinarum P581a, a strain of intestinal bacteria deglycosylating flavone C-glycosides

Flavone C-glycosides are not easily degraded because of their strong C-C bond between sugar moieties and aglycones. However, some bacteria such as intestinal species can produce specific enzymes to degrade them. In this study, a bacterial strain P581a, which is capable of deglycosylating flavone C-glycosides, was isolated from human intestinal bacteria and was identified as Enterococcus gallinarum by morphological examination, physiological and biochemical analysis and 16S rRNA gene sequencing. This strain may produce a specific flavonoside glycosidase. The activity of the enzyme in the culture medium containing different quantity of carbon sources was also studied, and it was found that the content of carbon sources is negatively correlated with the deglycosylation efficiency of this strain.