Biobased Sanitizer Delivery System for Improved Sanitation of Bacterial and Fungal Biofilms

Abstract

Biofilms can persist in food-processing environments because of their relatively higher tolerance and resistance to antimicrobials including sanitizers. In this study, a novel biobased sanitizer composition was developed to effectively target biofilms and deliver chlorine-based sanitizers to inactivate bacterial and fungal biofilms. The biobased composition was developed by encapsulating a chlorine-binding polymer in a biobased yeast cell wall particle (YCWP) microcarrier. This study demonstrates the high affinity of biobased compositions to bind target bacterial and fungal cells and inactivate 5 logs of model pathogenic bacteria and fungi in wash water without and with high organic load (chemical oxygen demand = 2000 mg/L) in 30 s and 5 min, respectively. For the sanitation of biofilms, this biobased sanitizer can inactivate 7 logs of pathogenic bacteria and 3 logs of fungi after 1 h treatment, whereas the 1 h treatment using conventional chlorine-based sanitizer can only achieve 2-3 log reduction for bacterial biofilms and 1-2 log reduction for fungal biofilms, respectively. The enhanced antimicrobial activity can be attributed to three factors: (a) localized high concentration of chlorine bound on the YCWPs; (b) high affinity of YCWPs to bind diverse microbes; and (c) improved stability in an organic-rich aqueous environment. In summary, these unique attributes of biobased carriers will significantly enhance the sanitation efficacy of biofilms, reduce the persistence and transmission of antimicrobial resistant microbes, limit the use of antimicrobial chemicals, and improve the cost-effectiveness of sanitizers.

Keywords: N-halamine; antifungal; antimicrobial; biofilm; particle-based sanitizer; yeast cell wall particles.