Milk protein-based edible films enriched with clove and camphor essential oils: Characterization, bioactivity, and potential applications against periodontal pathogens

Abstract

This study investigated milk protein (MP)-based edible films incorporated with clove and camphor essential oils (EOs) as antimicrobial agents against dental pathogens. Gas chromatography-mass spectrophotometry revealed clove oil contained 72.2 % eugenol while camphor oil contained 69.51 % citronellal. The optimum formulation as in Run 12 (2.5 % camphor oil + 3.0 % clove oil, 24 h contact time) achieved 100 % growth reduction against Streptococcus mutans, Aggregatibacter actinomycetemcomitans, and Porphyromonas gingivalis using Box-Behnken design. Clove oil films exhibited superior inhibition zones (15.25-19.83 mm) compared to camphor oil films (14.66-17.81 mm) at 3.0 % concentration. Tensile strength improved from 0.2 MPa (control) to 0.7 MPa (Run 12), with elongation at break increasing from 15 % to 80 %. Run 12 films demonstrated enhanced thermal stability with transitions at -15 °C (10.0 mW) versus -45 °C (7.1 mW) for controls. Clove oil films showed 75 % free radical scavenging activity compared to 62 % for camphor oil and 16 % for controls. Oral epithelial cell viability remained >90 % at concentrations up to 300 μg/mL, with IC50 exceeding 300 μg/mL. Cytogenetic analysis showed minimal chromosomal aberrations (1.5 % numerical, negligible structural) compared to control (0.5 %, 0 %) and mitomycin C (18 %, 20.1 %). These findings demonstrate that MP-based edible films with essential oils represent a promising, biocompatible approach for controlling dental pathogens.