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A Customizable Approach for the Enzymatic Production and Purification of Diterpenoid Natural Products
Published on: October 4, 2019
Conocarpan and Eupomatenoid-6 as Natural Prototypes for Antituberculosis Compounds
Lincoln Luís Silva1, Anderson Valdiney Gomes Ramos2, Debora Cristina Baldoqui2
1Department of Pharmacy, State University of Midwest Paraná, Guarapuava, Brazil.
International Journal of Microbiology
|June 15, 2026
Summary
Two neolignans from Piper solmsianum show promise for treating drug-resistant tuberculosis (TB). Conocarpan (1) demonstrated synergistic effects with rifampicin, indicating potential for TB and TB/HIV coinfection therapies.
Area of Science:
- Natural Product Chemistry
- Microbiology
- Pharmacology
Background:
- Tuberculosis (TB), caused by Mycobacterium tuberculosis (Mtb), remains a leading infectious disease.
- The rise of multidrug-resistant TB (MDR-TB) necessitates novel therapeutic agents.
- Piper solmsianum yielded two neolignans, conocarpan (1) and eupomatenoid-6 (2), for investigation.
Purpose of the Study:
- To evaluate the in vitro activity of conocarpan (1) and eupomatenoid-6 (2) against drug-susceptible and MDR-TB isolates.
- To assess the cytotoxicity of these neolignans in mammalian cell lines.
- To investigate the potential synergistic or antagonistic interactions with existing anti-TB and antiretroviral drugs.
Main Methods:
- Neolignans were isolated using high-performance liquid chromatography.
- In vitro activity was determined via resazurin microtiter assays against Mtb strains and other bacteria.
- Cytotoxicity was evaluated using MTT assays in various cell lines (J774.A1, HeLa, VERO, MRC-5).
- Drug combination assays assessed synergistic and antagonistic effects.
- ADME properties were predicted using Swiss ADME.
Main Results:
- Both compounds (1) and (2) exhibited activity against Mtb, Mycobacterium abscessus, and Staphylococcus aureus (MICs 3.90–125 μg/mL).
- Conocarpan (1) showed synergism with rifampicin; no antagonistic effects were observed with other drugs.
- Compounds displayed selectivity for bacteria over mammalian cells, with eupomatenoid-6 (2) being the least cytotoxic.
- Predicted ADME properties indicated high gastrointestinal permeability and compliance with Lipinski's rules.
Conclusions:
- Conocarpan (1) and eupomatenoid-6 (2) possess significant antibacterial activity.
- The synergistic interaction of conocarpan (1) with rifampicin highlights its potential for treating drug-resistant TB.
- These neolignans are promising candidates for further development, particularly for TB/HIV coinfection management.
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