Plant, Marine, and Microbial Natural Products as Novel Antiparasitic Therapeutics: Mechanistic Insights, Innovations, and Therapeutic Opportunities

Abstract

Background: Parasitic diseases are among the biggest contributors to worldwide morbidity and mortality; they are particularly debilitating to people living in tropical and subtropical climates. The increasing incidence of drug-resistant organisms has urged researchers to explore novel therapies from natural sources.
Objectives: To summarize the clinical efficacy and mechanisms of action of antiparasitic natural products in regard to the plant, marine and microbial origin of the natural product, within the context of understanding novel methods of action and the potential for high therapeutic value.
Methods: A literature search was completed on the topic of antiparasitic natural products (2000-2025) using PubMed/MEDLINE, Scopus, Web of Science, Embase and Google Scholar according to PRISMA 2020 standards. Studies reporting in vitro, in vivo or clinical evidence of antiparasitic activity of natural products with definitively described mechanism(s) of action were included.
Results: A total of 4,287 studies were identified, of which 127 studies satisfied inclusion criteria. Plant derived materials (alkaloids, terpenoids, flavonoids, phenolics) were effective against four parasite genera (Plasmodium, Leishmania, Trypanosoma and certain helminths). New mechanisms were demonstrated for marine-sourced natural products targeting parasite organelles. Microbial natural products support the development of global antiparasitic drug research efforts. Improvements in nanotechnology-enhanced delivery have yielded significant advancements in bioavailability.
Conclusions: Natural products offer excellent prospects as antimicrobial drug lead compounds. The development of genomic and metabolomic technologies and of nanomedicine is accelerating therapeutic progression toward clinical applications. Future priorities will be to establish standardizedreporting systems, develop clarity in mechanism(s) of action and devise combination strategies.