Dataset Information

Bioassay-guided isolation and identification of gametocytocidal compounds from Artemisia afra (Asteraceae).

ABSTRACT:

Background

Optimal adoption of the malaria transmission-blocking strategy is currently limited by lack of safe and efficacious drugs. This has sparked the exploration of different sources of drugs in search of transmission-blocking agents. While plant species have been extensively investigated in search of malaria chemotherapeutic agents, comparatively less effort has been channelled towards exploring them in search of transmission-blocking drugs. Artemisia afra (Asteraceae), a prominent feature of South African folk medicine, is used for the treatment of a number of diseases, including malaria. In search of transmission-blocking compounds aimed against Plasmodium parasites, the current study endeavoured to isolate and identify gametocytocidal compounds from A. afra.

Methods

A bioassay-guided isolation approach was adopted wherein a combination of solvent-solvent partitioning and gravity column chromatography was used. Collected fractions were continuously screened in vitro for their ability to inhibit the viability of primarily late-stage gametocytes of Plasmodium falciparum (NF54 strain), using a parasite lactate dehydrogenase assay. Chemical structures of isolated compounds were elucidated using UPLC-MS/MS and NMR data analysis.

Results

Two guaianolide sesquiterpene lactones, 1α,4α-dihydroxybishopsolicepolide and yomogiartemin, were isolated and shown to be active (IC₅₀ < 10 μg/ml; ~ 10 μM) against both gametocytes and intra-erythrocytic asexual P. falciparum parasites. Interestingly, 1α,4α-dihydroxybishopsolicepolide was significantly more potent against late-stage gametocytes than to early-stage gametocytes and intra-erythrocytic asexual P. falciparum parasites. Additionally, both isolated compounds were not overly cytotoxic against HepG2 cells in vitro.

Conclusion

This study provides the first instance of isolated compounds from A. afra against P. falciparum gametocytes as a starting point for further investigations on more plant species in search of transmission-blocking compounds.

SUBMITTER: Moyo P

PROVIDER: S-EPMC6408838 | biostudies-literature | 2019 Mar

REPOSITORIES: biostudies-literature

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Publications

Bioassay-guided isolation and identification of gametocytocidal compounds from Artemisia afra (Asteraceae).

Moyo Phanankosi P Kunyane Phaladi P Selepe Mamoalosi A MA Eloff Jacobus N JN Niemand Jandeli J Louw Abraham I AI Maharaj Vinesh J VJ Birkholtz Lyn-Marie LM

Malaria journal 20190308 1

<h4>Background</h4>Optimal adoption of the malaria transmission-blocking strategy is currently limited by lack of safe and efficacious drugs. This has sparked the exploration of different sources of drugs in search of transmission-blocking agents. While plant species have been extensively investigated in search of malaria chemotherapeutic agents, comparatively less effort has been channelled towards exploring them in search of transmission-blocking drugs. Artemisia afra (Asteraceae), a prominent ...[more]

PMID: 30849984

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Dataset Information

Bioassay-guided isolation and identification of gametocytocidal compounds from Artemisia afra (Asteraceae).

Background

Methods

Results

Conclusion

Publications

Bioassay-guided isolation and identification of gametocytocidal compounds from Artemisia afra (Asteraceae).

Similar Datasets

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