Antifungal activity of P3HB microparticles containing tebuconazole

Abstract

In this study, tebuconazole (TEB)-loaded poly-3-hydroxybutyrate (P3HB)-based microparticles were developed and comprehensively characterized. TEB-loaded microparticles with the initial loading amounts of the fungicide of 10, 25, and 50% of the polymer mass (TEB 10, TEB 25, and TEB 50%) were prepared using emulsion technique. Encapsulation efficiency of TEB varied from 59 to 86%. As the loading amount was increased, the average diameter of microparticles increased too, from 41.3 to 71.7 µm, while zeta potential was not influenced by TEB loading, varying between –32.6 and –35.7 mV. TEB was gradually released from the microparticles to the model medium, and after 60 d, from 25 to 43% of TEB was released depending on the content of the encapsulated fungicide. The data obtained from in vitro TEB release were fitted to different mathematical models. It was shown that the release profiles of TEB could be best explained by the Zero-order, Higuchi, and Hixson–Crowell models. The antifungal activity of the P3HB/TEB microparticles against phytopathogenic fungi Fusarium moniliforme and Fusarium solani was demonstrated by in vitro tests conducted in Petri dishes. Thus, hydrophobic agrochemicals (TEB) can be effectively encapsulated into P3HB microparticles to construct slow-release formulations.

Keywords:

• Antifungal activity
• encapsulation
• microparticles
• poly-3-hydroxybutyrate
• tebuconazole

Acknowledgements

The authors would like to thank Ivan Nemtsev (Federal Research Center Krasnoyarsk Scientific Center of the Siberian Branch of the RAS) for his assistance with SEM.

Disclosure statement

The authors disclose that no conflicting interests associated with the manuscript exist.

Additional information

Funding

This study was financially supported by Project “Agropreparations of the new generation: a strategy of construction and realization” (Agreement No 074-02-2018-328) in accordance with Resolution № 220 of the Government of the Russian Federation of April 9, 2010, “On measures designed to attract leading scientists to the Russian institutions of higher learning”.