Antibacterial and thermomechanical properties of composites of polylactic acid modified with capsicum oleoresin‐impregnated nanoporous silica

Abstract

Biodegradable composite films of poly(lactic acid) (PLA) modified with varying amounts of capsicum oleoresin (CO)‐impregnated nanoporous silica (SiCO) were prepared. The antimicrobial and thermomechanical properties of the PLA composites were carefully investigated. The Gram‐positive pathogenic bacteria (Staphylococcus aureus and Bacillus) and the Gram‐negative pathogenic bacteria (Escherichia coli and Salmonella enterica) tests established excellent antimicrobial properties of the composites even at small concentrations of SiCO. The microscopic (scanning electron micrograph) and spectroscopic (energy‐dispersive X‐ray) investigations manifested the uniformity of particle distribution. Although the addition of CO slightly decreased the thermal stability of the composite films, it marginally enhanced the mechanical properties and crystallinity. © 2019 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2019, 136, 47825.

Effects of solvent casted poly (lactic acid)/poly(ethylene glycol)/paraben derivative triazine films on antibacterial performance and cytotoxicity

“…shown to be more susceptible to PLA films than Gram-positive bacteria in some studies. 3,76,77 This is due to the differences in their bacterial cell wall structures. 78,79 Phospholipids, proteins, and lipopolysaccharides in the outer layer of gram-negative bacteria may have provided the permeability of some molecules.…”

“…Thus, it was also shown on agar plates that the films obtained were especially effective against E. coli . Gram‐negative bacteria have been shown to be more susceptible to PLA films than Gram‐positive bacteria in some studies 3,76,77 . This is due to the differences in their bacterial cell wall structures.…”

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