Antimicrobial Efficacy of Poly (DL‐lactide‐co‐glycolide) (PLGA) Nanoparticles with Entrapped Cinnamon Bark Extract against Listeria monocytogenes and Salmonella typhimurium

Abstract

Nanoencapsulation of active compounds using poly-(d,l-lactide-co-glycolide) (PLGA) is commonly used in the pharmaceutical industry for drug delivery and may have important applications in the food industry. Control of growth of foodborne bacteria with the goals of reducing the number of foodborne illness outbreaks, assuring consumers a safer food supply remains a priority in the food industry. Natural antimicrobials are an excellent way to eliminate pathogens without introducing chemical preservatives that consumers may find undesirable. Cinnamon bark extract (CBE) is an effective pathogen inhibitor isolated from cinnamon spice. PLGA nanoparticles containing CBE were produced using an emulsion-solvent evaporation method and characterized for size, polydispersity, morphology, entrapment efficiency, in vitro release and pathogen inhibition. PLGA with 2 different ratios of lactide to glycolide (65:35 and 50:50) were used to determine how polymer composition affected nanoparticle characteristics and antimicrobial potency. The size of the nanoparticles ranged from 144.77 to 166.65 nm and the entrapment efficiencies of CBE in 65:35 PLGA and 50:50 PLGA were 38.90% and 47.60%, respectively. The in vitro release profile at 35 °C showed an initial burst effect for both types of PLGA followed by a more gradual release of CBE from the polymer matrix. Both types of PLGA nanoparticles loaded with CBE were effective inhibitors of Salmonella enterica serovar Typhimurium and Listeria monocytogenes after 24 and 72 h at concentrations ranging from 224.42 to 549.23 μg/mL. The PLGA encapsulation improved delivery of hydrophobic antimicrobial to the pathogens in aqueous media.

Physicochemical Properties and Control Release of Aloe Vera (Aloe barbadensis Miller) Bioactive Loaded Poly (Lactic Co-Glycolide Acid) Synthesized Nanoparticles

“…No significant differences (p > 0.05) of the materials synthesized either in the PLGA unloaded NP and FDG loaded NP was observed on the PDI values of 0.2 (Table 1), a similar observation was also reported by Hill et al [18] for a cinnamon bark extract encapsulated with PLGA NP. The LG loaded NP shows a less homogeneity compared to the FD loaded NP with a PDI of 0.3 as shown in Table 1, this was also manifested in the broadening of the PSD bell-shape-curved as shown in Figure 1(c).…”

“…The EE of the FDG synthesized is significantly different (p < 0.05) from the LG loaded NP, hence the values determined were 87% and 67%, respectively. These values are much higher than 48% and 39% for PLGA50-CBE and PLGA65-CBE, receptively reported by Hill et al [18]. The EE values for the FDG loaded NP was much higher due to the increased concentration of the bioactive compounds due to freeze drying.…”

“…Nanoparticles synthesize with polymers such as Poly (Lactic co-Glycolide Acid) were reported to have a high EE due to its molecular structure that is associated to its active sites [17]. An EE of 47.6% and 38.9% for cinnamon bark extract loaded in PLGA-50 and PLGA-65 NP, respectively was reported by Hill et al [18]. Peng et al [19] also reported about 80% time release of plant oil curcumin encapsulated with PF127 micelles during 6-h period at 37˚C.…”

Recent Developments in Application of Polymeric Nanoparticles as Drug Carriers

“…The results revealed a sustained release of the antibiotic from the prepared formulation and its better permeation across rat intestines as compared to the free drug [24]. A curious instance has been explored by Hill and co-workers [21], who demonstrated that PLGA nanoparticles loaded with the natural antimicrobial cinnamon bark extract are effective inhibitors of Salmonella typhimurium and Listeria monocytogenes. The authors highlighted the potential of the as-prepared system for the food industry to help prevent foodborne diseases [21].…”

“…Intriguingly, the encapsulation or dispersion of drugs with a polymeric matrix might protect the drug molecules from premature release and degradation before reaching the targeted site [18]. Polymer-based nanoparticles can be used as the carrier for numerous biologically active molecules including drugs [18], proteins [7], monoclonal antibodies [13], nucleic acids [19,20], biological extracts [16,21] and others [22]. This review will be especially concerned with the application of polymer-based nanoparticles for the treatment of various disease entities including bacterial [23,24], fungal [25] and parasitic [26] infections, ulcers [11], hypertension [12], angina [8], glaucoma [9], uveitis [27], asthma [22], cancer [15,28], neurodegenerative disease [29] and many others [30,31].…”