ORIGINAL RESEARCH article
Front. Microbiol.
Sec. Infectious Agents and Disease
This article is part of the Research TopicEpidemiology and Control of Emerging/Re-emerging Poultry and Waterfowl DiseasesView all 8 articles
Spirulina platensis as a Novel Natural Antimicrobial Against Macrolide-Resistant Mycoplasma gallisepticum in Poultry
Provisionally accepted
SABRINA ZIDI1*
Nadine KHADRAOUI1
RYM ESSID1
Imen CHNIBA1
Sarra ABASSI1
Salim Chibani1Maher GAZBAR1Behija MLIK1Hédi GAZBAR1
Wassim Almawi2
Boutheina Ben Abdelmoumen Mardassi1*- 1Institut Pasteur de Tunis, Tunis, Tunisia
- 2Universite de Tunis El Manar Faculte des Sciences de Tunis, Tunis, Tunisia
Select one of your emails
You have multiple emails registered with Frontiers:
Notify me on publication
Please enter your email address:
If you already have an account, please login
You don't have a Frontiers account ? You can register here
Background. Antimicrobial resistance in Mycoplasma gallisepticum (MG) poses a significant threat to global poultry production, as traditional antibiotics, particularly macrolides, are becoming increasingly ineffective due to growing resistance. This study investigates Spirulina platensis as a natural antimicrobial candidate against macrolide-resistant MG strains. Materials and Methods. We tested 64 field isolates, along with the reference strain ATCC 15302, using broth microdilution. Minimum inhibitory concentrations (MICs) were measured for conventional antibiotics (doxycycline, oxytetracycline, tylosin, tilmicosin, Aivlosin) and Spirulina extract. Principal Component Analysis and correlation matrices were employed to investigate therapeutic relationships, while cytotoxicity assays evaluated safety profiles. Results. High resistance rates were observed for the macrolides tilmicosin (87.5%) and tylosin (68.75%). Spirulina platensis showed in vitro antimicrobial activity against the tested isolates, with MICs ranging from 3.9 to 1000 µg/mL; 65% of isolates were inhibited at concentrations of 250 µg/mL or lower, indicating measurable activity and supporting further investigation as a natural antimicrobial compound. Correlation analyses indicated weak or negligible associations with conventional antibiotics (p < 2.2 × 10⁻¹⁶), reflecting a distinct activity profile. Additionally, Spirulina exhibited no cytotoxicity up to 4000 µg/mL, with a selectivity index of 512.8, indicating a favorable in vitro safety profile. Conclusion. These findings suggest that Spirulina platensis acts as a uniquely mechanistic, non-toxic antimicrobial agent that can bypass existing resistance mechanisms. Further in vivo validation and mechanistic investigations are necessary to assess its potential as an alternative therapeutic option for poultry health management and combating antimicrobial resistance.
Keywords: antimicrobial resistance, avian, Broth microdilution, MIC, Mycoplasma gallisepticum, Spirulina platensis
Received: 16 Dec 2025; Accepted: 05 Feb 2026.
Copyright: © 2026 ZIDI, KHADRAOUI, ESSID, CHNIBA, ABASSI, Chibani, GAZBAR, MLIK, GAZBAR, Almawi and Ben Abdelmoumen Mardassi. This is an open-access article distributed under the terms of the Creative Commons Attribution License (CC BY). The use, distribution or reproduction in other forums is permitted, provided the original author(s) or licensor are credited and that the original publication in this journal is cited, in accordance with accepted academic practice. No use, distribution or reproduction is permitted which does not comply with these terms.
* Correspondence:
SABRINA ZIDI
Boutheina Ben Abdelmoumen Mardassi
Disclaimer: All claims expressed in this article are solely those of the authors and do not necessarily represent those of their affiliated organizations, or those of the publisher, the editors and the reviewers. Any product that may be evaluated in this article or claim that may be made by its manufacturer is not guaranteed or endorsed by the publisher.