Dual surface functionalised curcumin-shellac nano-delivery system with enhanced antimicrobial action

Area of Science:

• Materials Science
• Nanotechnology
• Microbiology

Background:

• Curcumin (CUR) possesses antimicrobial properties but requires formulation for enhanced efficacy.
• Shellac, a natural polymer, and Poloxamer 407 can form stable nanoparticles.
• Cationic surface modification can improve nanoparticle interaction with microbial surfaces.

Purpose of the Study:

• To develop and characterize curcumin-loaded, cationically functionalized shellac nanoparticles (CUR-NPs).
• To evaluate the enhanced antimicrobial activity of these CUR-NPs against bacteria, yeast, and algae.
• To investigate the role of cationic surface functionalization in improving CUR's bioavailability and efficacy.

Main Methods:

• Shellac-based nanoparticles loaded with curcumin were fabricated using solvent attrition and co-precipitation.
• Nanoparticles were surface-functionalized with octadecylthrimethylammonium bromide (ODTAB).
• Encapsulation efficiency, release kinetics, and antimicrobial activity against *E. coli*, *C. reinhardtii*, and *S. cerevisiae* were assessed.

Main Results:

• Stable CUR-loaded shellac nanoparticles with optimal ratios of shellac and Poloxamer 407 were successfully produced.
• Cationic surface functionalization significantly enhanced the antimicrobial activity of curcumin against all tested microorganisms.
• Enhanced efficacy is attributed to electrostatic attraction between cationic NPs and anionic microbial cell walls, promoting localized CUR delivery.

Conclusions:

• Cationic functionalization of shellac nanoparticles amplifies curcumin's antimicrobial effects.
• This nanotechnology approach offers a promising strategy for developing natural, antibiotic-free antimicrobial formulations.
• The findings suggest potential applications in agriculture, medicine, and industry for controlling microbial growth.