Components in Lentinus edodes mushroom with anti-biofilm activity directed against bacteria involved in caries and gingivitis

The present study investigated the compounds present in the low molecular mass fraction ofLentinusedodesmushroom (shiitake) extract and their anti-virulence activity against oral pathogens (reference andclinicalStreptococcus mutans,Actinomyces naeslundii, andPrevotella intermediastrains). Oxalic, succi-nic, and quinic acids, and adenine, inosine, and uridine were identified by HPLC-DAD-ESI-MS/MS. Theiranti-biofilm production and preformed biofilm disaggregation activities were studied using commercialstandard compounds at different concentrations. As regardsS. mutans, the highest activity was shown byadenine at 5 mg mL−1both in the biofilm inhibition (BI 50%) and biofilm disaggregation tests (BD 20%).ConsideringA. naeslundii, BI values close to 80% were registered for oxalic acid at 1 mg mL−1and2mgmL−1and BD 50% for quinic acid at 3 mg mL−1. A weaker activity was found againstP. intermedia.Furthermore, different mixtures of the commercial standards were tested showing that the activity ofa compound can be strongly and sometimes negatively affected by the presence of the other compounds