A contribution to pharmaceutical biology of freshwater sponges

<p><i>In vitro</i> anti-tumour and anti-radical activities of the acetone extract of the freshwater sponge <i>Ochridaspongia rotunda</i> were the subject of this study. The extract was found to be highly cytotoxic to human lung tumour cell line A-549 reaching IC<sub>50</sub> value of 5.01 ± 0.21 μg/mL. Indeed, it displayed only 2-fold less anti-tumour activity than doxorubicin (IC<sub>50</sub> value 2.42 ± 0.13 μg/mL) used as a positive control. The same extract was also found to be almost 37-fold more selective against A-549 vs. MRC-5 (normal) lung cells, in difference to weak selectivity of doxorubicin (less than 3-fold). Its profound anti-DPPH radical activity comparable to that of quercetin (IC<sub>50</sub> values 3.68 ± 0.19 and 3.14 ± 0.09 μg/mL, respectively) coupled with no signs of genotoxicity in the comet assay (MRC-5 cell line, vs. doxorubicin) has actually implicated the importance of this animal bioresource in searching for pharmaceutically useful bioactive compounds of natural origin.</p>