Phytotoxicity and cytogenotoxic effects of extracts from the medicinal bark of <i>Rhamnus purshiana</i> DC. (Rhamnaceae)

Natural products, although frequently associated with beneficial effects and considered harmless, still require thorough analysis; therefore, their bioactive compounds need to be used with caution. Biological assays using plant models represent an appropriate alternative for evaluating the cytogenotoxicity associated with these products. In this study, the phyto- cytotoxic potential of extracts from the bark of <i>Rhamnus purshiana</i> DC. a species widely used for treatment of constipation was investigated due to its anthraquinone content. To this end, seeds of <i>Lactuca sativa</i> L. were employed in phyto-cytogenotoxic assays under chronic exposure to lyophilized and spray-dried extracts. The results showed that extraction methods directly influence the phytochemical composition and biological effects of the extracts. Both extracts exhibited high anthraquinone content, expressed as cascaroside A, with concentrations ranging from 45.65 to 72.17 μg/ml. The spray-dried extract demonstrated a more potent inhibitory effect on morphological parameters, such as root elongation, while lyophilized extract exhibited higher cytotoxicity. Both extracts induced mitodepressive effects and aneugenic damage. Notably, the lyophilized extract induced a 300% increase in mitotic abnormalities compared to control, with a higher frequency of C-metaphases and stickiness. Although <i>R. purshiana</i> is widely used in traditional medicine, the scarcity of studies on cascaroside A raises concerns regarding socio-environmental safety and continued use of this species in dietary supplements.