Antitrypanosomal Constituents from Brasenia schreberi and Nymphaea lotus Used in a Single Herbal Preparation against Sleeping Sickness in Angola

Vahekeni, N.; Brillatz, T.; Rahmaty, M.; Cal, M.; Keller-Maerki, S.; Rocchetti, R.; Kaiser, M.; Sax, S.; Mattli, K.; Wolfram, E.; Marcourt, L.; Queiroz, E.F.; Wolfender, J.-L.; Mäser, P. Antiprotozoal Activity of Plants Used in the Management of Sleeping Sickness in Angola and Bioactivity-Guided Fractionation of Brasenia schreberi J.F.Gmel and Nymphaea lotus L. Active against T. b. rhodesiense. Molecules 2024, 29, 1611. Vahekeni, N.; Brillatz, T.; Rahmaty, M.; Cal, M.; Keller-Maerki, S.; Rocchetti, R.; Kaiser, M.; Sax, S.; Mattli, K.; Wolfram, E.; Marcourt, L.; Queiroz, E.F.; Wolfender, J.-L.; Mäser, P. Antiprotozoal Activity of Plants Used in the Management of Sleeping Sickness in Angola and Bioactivity-Guided Fractionation of Brasenia schreberi J.F.Gmel and Nymphaea lotus L. Active against T. b. rhodesiense. Molecules 2024, 29, 1611.

Abstract

Folk medicine is widely used in Angola, even for human African trypanosomiasis (sleeping sickness) in spite of the fact that the reference treatment is available for free. Aiming to validate herbal remedies in use, we have selected nine medicinal plants and assessed their antitrypanosomal ac-tivity. 122 extracts were prepared using different plant parts and solvents. 15 extracts from seven different plants exhibited in vitro activity against Trypanosoma brucei rhodesiense bloodstream forms >70% at 20 µg/ml. The dichloromethane extract of Nymphaea lotus (leaves and leaflets) and the ethanolic extract of Brasenia schreberi (leaves) had IC50 values ≤10 µg/ml. These two aquatic plants are of particular interest. They are being co-applied in the form of a decoction of leaves because they are considered by local healers as male and female of the same species, the ethnotaxon “longa dia simbi”. Bioassay-guided fractionation led to the identification of eight active molecules: gallic acid (IC50 0.5 µg/ml), methyl gallate (IC50 1.1 µg/ml), 2,3,4,6-tetragalloyl-glucopyranoside, ethyl gallate (IC50 0.5µg/ml), 1,2,3,4,6-pentagalloyl-β-glucopyranoside (IC50 20µg/ml), gossypet-in-7-O-β-glucopyranoside (IC50 5.5µg/ml), and hypolaetin-7-O-glucoside (IC50 5.7µg/ml) in B. schreberi, and 5-[(8Z,11Z,14Z)-heptadeca-8,11,14-trienyl] resorcinol (IC50 5.3µg/ml) not described to date in N. lotus. Five of these active constituents were detected in the traditional preparation. This work provides the first evidence for the ethnomedicinal use of these plants in the management of sleeping sickness in Angola.

Keywords

ethnopharmacology; African medicinal plant; antiprotozoal; trypanosomiasis; Brasenia schreberi; Nymphaea lotus; Angola

Subject

Biology and Life Sciences, Parasitology

Copyright: This is an open access article distributed under the Creative Commons Attribution License which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.

Download PDF Download Supplementary

Comments (0)

Not displayed online.

Importance: How significant is the paper to the field?

Outstanding/highlight paper

Significant contribution

Incremental contribution

No contribution

I am not qualified to judge

Soundness of evidence/arguments presented:

Conclusions well supported

Most conclusions supported (minor revision needed)

Incomplete evidence (major revision needed)

Hypothesis, unsupported conclusions, or proof-of-principle

I am not qualified to judge

Please leave your comment to this article below.

Mathematical equations can be typed in either LaTeX formats \\[ ... \\] or $$ ... $$, or MathML format <math> ... </math>. Try the LaTeX or MathML example.

Type equation:

Preview:

Copy equation into message below

Close menu

Please click a symbol to insert it into the message box below:

Please enter the link here:

Please enter a valid URL

Optionally, you can enter text that should appear as linked text:

Copy link into message below

Close menu

Please enter or paste the URL to the image here (please only use links to jpg/jpeg, png and gif images):

Please enter a valid URL

Copy image into message below

Close menu

Type author name or keywords to filter the list of references in this group (you can add a new citation under Bibliography):

No existing citations in Discussion Group

Wikify editor is a simple editor for wiki-style mark-up. It was written by MDPI for Sciforum in 2014. The rendering of the mark-up is based on Wiky.php with some tweaks. Rendering of mathematical equations is done with MathJax. Please send us a message for support or for reporting bugs.

Close menu

Please declare any conflicts of interest you may have with this paper, financial or otherwise.

I do not have a conflict of interest

I would like to declare a conflict of interest

Display my name on the website Send my name and email address to the authors

Captcha

Renew

I accept the following conditions:

Comments must follow the standards of professional discourse and should focus on the scientific content of the article. Insulting or offensive language, personal attacks and off-topic remarks will not be permitted. Comments must be written in English. Preprints reserves the right to remove comments without notice. Readers who post comments are obliged to declare any competing interests, financial or otherwise.

We encourage comments and feedback from a broad range of readers. See criteria for comments and our Diversity statement.

Leave a public comment
Send a private comment to the author(s)

* All users must log in before leaving a comment

what’s this?

Add a record of this review to Publons to track and showcase your reviewing expertise across the world’s journals.

Downloads 0

Comments 0

Metrics 0

Get PDF Supplementary Files Cite Share 0

Bookmark BibSonomy Mendeley Reddit Delicious

Alerts

Notify me about updates to this article or when a peer-reviewed version is published.

Preprints.org is a free preprint server subsidized by MDPI in Basel, Switzerland.

MDPI Initiatives

SciProfiles
Sciforum
Encyclopedia
MDPI Books
Scilit
Proceedings
JAMS

Important links

How it Works
Advisory Board
FAQ
Friendly Journals
Instructions for Authors
About
Statistics

Choose the area that interest you and we will send you notifications of new preprints at your preferred frequency.

Disclaimer

We use cookies on our website to ensure you get the best experience.
Read more about our cookies here.

RSS feed for

Preprints: The Multidisciplinary Preprint Platform

Paste the URL in your RSS reader:

https://www.preprints.org/rss

If you want to subscribe our website in subject-wide, you could find the URL by choosing in the following:

https://www.preprints.org/rss

Please note that by using ScienceDirect RSS feeds, you agree to our Terms of Use and Privacy Policy.