Development of sodium alginate-gelatin-graphene oxide complex film for enhancing antioxidant and ultraviolet-shielding properties

The study aimed to investigate the antioxidant and ultraviolet-shielding properties of sodium alginate-gelatin-graphene oxide ternary films by adding rosemary extract (RE). Polyvinylpyrrolidone (PVP) was used to overcome the shortcoming that RE decreased the mechanical properties of films. The addition of 0.1 % PVP enhanced the tensile strength of the films by 13.61 MPa without significant reduction in elongation at break. RE markedly decreased the light transmittance of PVP-containing film by 39.40 %-52.55 % in the 300-400 nm region, showing excellent ultraviolet-shielding capacity of RE. Additionally, films with RE and PVP showed superior 1,1-diphenyl-2-picrylhydrazyl radical scavenging activity in water and 50 % ethanol. The peroxide value of soybean oil sealed with films containing RE and PVP was 0.51 times of that sealed with the ternary film after 30 days of storage, indicating excellent antioxidant activity of RE. This study provided a prospect for application of sodium alginate-gelatin based functional packaging materials.

Automated summary

The study found that adding rosemary extract and polyvinylpyrrolidone can significantly enhance the antioxidant and ultraviolet-shielding properties of ternary films, improving their mechanical properties, reducing light transmittance, enhancing radical scavenging activity, and exhibiting excellent antioxidant activity.