| dc.description.abstract | The use of natural products as chemotherapeutic agents is well established. However, many
are associated with undesirable side effects, including high toxicity and instability. Previous reports
on the cytotoxic activity of pyrroloiminoquinones isolated from Latrunculid sponges against cancer
cell lines revealed extraordinary activity at IC50 of 77nM for discorhabdins. Their general lack of
selectivity against the cancer and normal cell lines, however, precludes further development. In this
study, extraction of a South African Latrunculid sponge produced three known pyrroloiminoquinone
metabolites (14-bromodiscorhabdin C (5), Tsitsikammamine A (6) and B (7)). The assignment of
the structures was established using standard 1D and 2D NMR experiments. To mitigate the lack
of selectivity, the compounds were loaded onto gold nanoparticles synthesized using the aqueous
extract of a brown seaweed, Sargassum incisifolium (sAuNPs). The cytotoxicity of the metabolites alone,
and their sAuNP conjugates, were evaluated together with the known anticancer agent doxorubicin
and its AuNP conjugate. The compound-AuNP conjugates retained their strong cytotoxic activity
against the MCF-7 cell line, with >90% of the pyrroloiminoquinone-loaded AuNPs penetrating the
cell membrane. | en_US |
