Antimicrobial and antibiofilm effects of trans-cinnamic acid nanoemulsion and its potential application on lettuce. (August 2018)

• Record Type: Journal Article
• Authors: Letsididi, Kekgabile S.; Lou, Zaixiang; Letsididi, Rebaone; Mohammed, Khalid; Maguy, Bibole L.
• Is Part Of: Lebensmittel-Wissenschaft + Technologie =. Volume 94(2018)
• Page Start: 25
• Page End: 32
• Publication Date: 2018-08
• Subjects: Trans-cinnamic acid -- Nanoemulsion -- Antimicrobial -- Biofilm -- Inhibition; Food industry and trade -- Periodicals; Food -- Composition -- Periodicals; Microbiology -- Periodicals; Nutrition -- Periodicals; 664.005
• DOI: 10.1016/j.lwt.2018.04.018
• Languages: English
• ISSNs: 0023-6438

Abstract

Abstract: A stable low-energy spontaneous trans -cinnamic acid ( trans -CA) nanoemulsion with a particle size of 46.7 ± 1 nm, polydispersity indice of 0.27 ± 0.01 was formulated. Antimicrobial effects of trans -CA nanoemulsion displayed minimum inhibitory concentration (MIC) of 0.78 mg/mL and minimum bactericidal concentration (MBC) of 3.13 mg/mL for Staphylococcus aureus while Salmonella typhimurium had MIC and MBC of 1.56 and 3.13 mg/mL, respectively. However, Pseudomonas aeruginosa showed an MIC and MBC of 3.13 and 6.25 mg/mL respectively. Biofilm formation inhibition showed that the concentrations of trans -CA nanoemulsion required to inhibit ≥50% biofilm formation by S. aureus, S. typhimurium and P. aeruginosa were 0.1, 0.2 and 0.39 mg/mL respectively. As for biofilm eradication, the concentrations required to eradicate ≥80% biofilm formed by S. aureus, S. typhimurium and P. aeruginosa were 0.78, 6.25 and 6.25 mg/mL, respectively. When applied to fresh-cut lettuce, nanoemulion displayed 65% reduction of aerobic mesophilic bacteria and 61% reduction of aerobic psychrophilic bacteria. These results demonstrated that trans -CA nanoemulsion has potential to be used in preservation and extension of fresh-cut lettuce shelf-life. Highlights: Trans -cinnamic acid nanoemulsion displayed MIC of 0.78 mg/mL for S. aureus . This nanoemulsion reduced S. aureus by 8 logs after 15 min of incubation. Biofilm formation inhibition ≥50% for S. aureus required 0.1 mg/mL of nanoemulsion. P. aeruginosa was more resistant to the nanoemulsion with MIC of 3.13 mg/mL. Reductions of mesophilic and psychrophilic bacteria on lettuce were around 60%.