Tannic acid-layered hydroxide salt hybrid: assessment of antibiofilm formation and foodborne pathogen growth inhibition.

Abstract

Pathogenic bacteria in food are a public health problem worldwide. Polyphenolic bioactive compounds with antimicrobial activity and antioxidant capacity represent a tangible alternative to overcome this problem. To preserve the biological functions of phenolic compounds such as tannic acid, which has been described to possess antioxidant and antimicrobial activity, this study describes the synthesis of a zinc nanohydroxide to stabilize its properties. Characterization by XRD, FT-IR, SEM, DLS, and UV-vis evidenced the presence of tannic acid in the nanohybrid TA-Zn-LHS which was further confirmed by DPPH, ABTS and FRAP antioxidant activity techniques. Bacterial growth inhibition of Escherichia coli ATCC 8739, Salmonella Enteritidis, and Staphylococcus aureus ATCC 25923 was over 80% at 50mg/mL of the TA-Zn-LHS and over 90% with Zn-LHS. Antibiofilm evaluation of these same strains showed biofilm formation inhibition > 90% and > 80% for Zn-LHS and TA-Zn-LHS, respectively. The toxicity evaluation of the materials in Artemia salina showed a classification of the materials as non-toxic to slightly toxic in concentrations up to 1mg/mL. These results allow us to introduce a new nanohybrid useful for food safety with safe biological functions.