Antimicrobial activity and cytotoxicity of endophytes from Scapania verrucosa Heeg.

We evaluated the antibacterial activity and cytotoxicity of endophytes isolated from Scapania verrucosa Heeg., which belongs to the liverwort class. A total of 49 endophytic fungi were isolated from S. verrucosa and classified into seven genera and one family in our previous study. In this study, the cytotoxic activity of the endophytes was assessed using the brine shrimp lethality bioassay, seven of which showed potent toxicity against the brine shrimp with 50% lethal concentration values less than 20 µg/mL. T-30 was the most toxic, with a 50% lethal concentration value of 7.15 µg/mL. Moreover, T-27 exhibited the strongest antibacterial activity against Staphylococcus aureus, with minimal inhibitory concentrations below 0.25 and 4 mg/mL, which can inhibit the growth of two standard strains - ATCC 25923 (methicillin-sensitive S. aureus) and ATCC 43300 (methicillin-resistant S. aureus) - in a time-dependent manner, respectively. These results suggest that endophytes in S. verrucosa are the sources for the production of natural bioactive products and thus warrant further investigation.