Ultraviolet protection of Bacillus thuringiensis through microencapsulation with Pickering emulsion method

Area of Science:

• Biotechnology
• Materials Science
• Environmental Science

Background:

• Bacillus thuringiensis (Bt) is a biopesticide susceptible to UV-A radiation, limiting its efficacy.
• Developing UV-stable formulations is crucial for enhancing Bt's field performance.
• Pickering emulsion offers a novel approach for encapsulating biological agents.

Purpose of the Study:

• To create a UV-A radiation-stable encapsulated formulation of Bacillus thuringiensis (Bt).
• To evaluate the protective efficacy of the colloidosome formulation against UV-A deactivation.
• To assess spore viability and insecticidal activity on Ephestia kuehniella (E. kuehniella) larvae under UV-A.

Main Methods:

• Utilized Pickering emulsion technique with latex particles, GO nanosheets, olive oil, ethanol, and water to encapsulate Bt.
• Formed Bt-loaded colloidosome microcapsules.
• Measured Bt spore viability and mortality rates of E. kuehniella larvae exposed to UV-A radiation.

Main Results:

• The encapsulated Bt formulation demonstrated significant protection against UV-A induced deactivation.
• Optimal protection of Bt viability was observed at a formulation concentration of 0.045%.
• Encapsulated Bt significantly increased E. kuehniella larval mortality under UV-A irradiation compared to unencapsulated Bt.

Conclusions:

• Colloidosome microcapsules produced via Pickering emulsion effectively protect Bacillus thuringiensis against UV-A radiation.
• This formulation enhances Bt stability and insecticidal activity under UV-A exposure.
• The developed encapsulation strategy shows promise for improving biopesticide performance in agricultural applications.