Version 2 2024-01-08, 13:36Version 2 2024-01-08, 13:36
Version 1 2024-01-02, 16:03Version 1 2024-01-02, 16:03
journal contribution
posted on 2024-01-08, 13:36authored byAna M. Ferreira, Isabela Sales, Sónia A. O. Santos, Tiago Santos, Fátima Nogueira, Silvana Mattedi, Simão P. Pinho, João A.
P. Coutinho, Mara G. Freire
Artemisinin, a drug used to treat
malaria, can be chemically synthesized
or extracted from Artemisia annua L. However, the
extraction method for artemisinin from biomass needs to be more sustainable
while maintaining or enhancing its bioactivity. This work investigates
the use of aqueous solutions of salts and ionic liquids with hydrotropic
properties as alternative solvents for artemisinin extraction from Artemisia annua L. Among the investigated solvents, aqueous
solutions of cholinium salicylate and sodium salicylate were found
to be the most promising. To optimize the extraction process, a response
surface method was further applied, in which the extraction time,
hydrotrope concentration, and temperature were optimized. The optimized
conditions resulted in extraction yields of up to 6.50 and 6.44 mg·g–1, obtained with aqueous solutions of sodium salicylate
and cholinium salicylate, respectively. The extracts obtained were
tested for their antimalarial activity, showing a higher efficacy
against the Plasmodium falciparum strain compared
with pure (synthetic) artemisinin or extracts obtained with conventional
organic solvents. Characterization of the extracts revealed the presence
of artemisinin together with other compounds, such as artemitin, chrysosplenol
D, arteannuin B, and arteannuin J. These compounds act synergistically
with artemisinin and enhance the antimalarial activity of the obtained
extracts. Given the growing concern about artemisinin resistance,
the results here obtained pave the way for the development of sustainable
and biobased antimalarial drugs.