Spectroscopic exploration of mode of binding of ctDNA and BSA with acridone alkaloids isolated from Zanthoxylum leprieurii (Rutaceae)

Zanthoxylum leprieurii is a medicinal plant widely studied due to its great phytochemical diversity, especially its acrinonic alkaloids, which have shown to be promising anticancer candidates. The aim of this work was to promote the isolation of acridonic alkaloids from fruits of Z. leprieurii and carried out absorption and fluorescence spectroscopy studies with calf thymus DNA and BSA. Five acridone alkaloids have been isolated, including the first description of 3-desmethoxy arborinine (2). In the study of interaction with biomacromolecules it was observed that all compounds show interaction with calf thymus DNA and BSA. Compound 2 promoted the bigger increase in BSA fluorescence (3.01%) with a lower fluorescence quenching constant (Ksv = 0.13 × 10⁴). Taken together, these results reaffirm the great phytochemical diversity of Z. leprieurii, and show that acridonic alkaloids have an affinity with both DNA and BSA, therefore providing clues to their mechanisms of action related to their anticancer activities.