ENHANCEMENT OF ANTIMICROBIAL ACTIVITIES OF NATURALLYOCCURRING PHENOLIC COMPOUNDS BY NANOSCALEDELIVERY AGAINST LISTERIA MONOCYTOGENES, ESCHERICHIACOLI O157:H7 AND SALMONELLA TYPHIMURIUM IN BROTHAND CHICKEN MEAT SYSTEM

摘要

Phenolic compounds commonly occurring in fruits, vegetables and tea were studiedfor their effects on Listeria monocytogenes (L.m.), Escherichia coli O157:H7 (E.c.) andSalmonella Typhimurium (S.T.) in brain–heart infusion broth (BHI) and meatsystem. Incubated at 37C for 72 h in BHI, gentistic, benzoic and vanillic acids inhibitedL.m., E.c and S.T. at 5,000 mg/mL by 2.8 to 3.0 log CFU/mL, 2.8 to 3.0 logCFU/mL and 2.7 to 2.9 log CFU/mL, respectively. Encapsulation of benzoic acid(1,100 mg/mL) in polylactic-co-glycolic acid nanoparticles inhibited 6.5 logCFU/mL of L.m. and S.T., and 6.0 log CFU/mL of E.c. at 48 h. In raw and cookedchicken meat systems, nanoparticle delivery of benzoic acid was effective against S.T.and L.m. (1.0 and 1.6 log CFU/g reduction of S.T. and 1.1 and 3.2 log CFU/g reductionof L.m. compared with 1.2 log CFU/g without nanoparticles on the days 9 and14 of storage, respectively). These findings demonstrate the efficacy of phenolics onpathogen reduction delivered by nanoparticles and their potential for commercialfood safety applications.