Physical and antimicrobial properties of cinnamon bark oil co-nanoemulsified by lauric arginate and Tween 80

Abstract

Lauric arginate (LAE) is a water-soluble cationic surfactant which has antimicrobial activity against a broad spectrum of foodborne pathogens. Some spice essential oils are effective lipophilic antimicrobials. Combining both antimicrobials may reduce their usage levels and possible negative sensory impacts when applied in complex food matrices. The objective of this study was to combine a nonionic surfactant (Tween 80) with LAE to form stable nanoemulsions with cinnamon bark essential oil (CBO) and to characterize the antimicrobial activity of these nanoemulsions. CBO was homogenized at 1% w/w in the aqueous phase with 3% w/w Tween 80 and 0.05-0.375% w/w LAE, followed by heating at 90°C for 30min to obtain final emulsions. With 0.125% and higher LAE, transparent emulsions with ~100nm in hydrodynamic diameter were observed to be stable during 30-day storage at 21°C. Antimicrobial activities of the nanoemulsion prepared with Tween 80 and 0.375% w/w LAE were studied. The respective minimum inhibitory concentrations (MICs) of the nanoemulsion in tryptic soy broth (TSB) were 12, 7, and 8ppm LAE for Salmonella enteritidis, Escherichia coli O157:H7, and Listeria monocytogenes, while those of free LAE were 11, 6, and 6ppm, respectively. MICs of CBO were 400ppm for the tested bacteria and Tween 80 at 6% w/w did not show inhibitory effect. Growth kinetics of the bacteria in TSB treated with the nanoemulsion or individual components at concentrations corresponding to the MICs of free LAE showed that binding among the LAE and Tween 80 and CBO components resulted in the antibacterial activity of nanoemulsion being lower than same concentrations of free LAE and CBO. Conversely, little difference was observed for the individual antimicrobials and the nanoemulsion in 2% reduced fat milk, and 750ppm LAE and 2000ppm CBO were observed to be the dominant antimicrobial against Gram-positive and Gram-negative bacteria, respectively. The growth of L. monocytogenes in 2% reduced fat milk at 4°C was not observed when treated by the nanoemulsion corresponding to 187.5ppm LAE and 500ppm CBO. Therefore, stable and transparent nanoemulsions of EOs can be prepared with the combination of LAE and Tween 80 without compromising antimicrobial activities.

Changes in characteristics of nanoemulsion of cinnamon oil and their relationships with instability mechanisms during storage

“…Ostwald ripening inhibition basically can be achieved by reducing the solubility of oil by incorporating water insoluble lipid such as corn oil (Ziani, Chang, McLandsborough, & McClements, ) and its combination with MCT (Chang, McLandsborough, & McClements, ). Besides, it can be retarded by the use of emulsifiers that highly effective at decreasing the interfacial tension (Kabalnov, Weers, Arlauskas, & Tarara, ; Weers, ) such as the use of lechitin (Hilbig et al, ; Moghimi, Ghaderi, Rafati, Aliahmadi, & McClements, ), lauric arginate (Ma, Davidson, Critzer, & Zhong, ), or increasing the thickness of the membrane (Weers, ). The use of mixed emulsifiers to modify the interfacial properties of emulsion droplets can also be considered to improve the stability of nanoemulsion (McClements & Jafari, ).…”

“…Essential oils have been widely used in food flavoring due to their high content of volatile aroma compounds. Their uses in the development of natural food ingredients have gained considerable interest as they have also other functionalities such as antimicrobials (Burt, ; Hilbig, Ma, Davidson, Weiss, & Zhong, ; Huang, Liu, Jia, & Luo, ; Jiménez, Domínguez, Pascual‐Pineda, Azuara, & Beristain, ; Lin, Dai, & Cui, ) and antioxidant, which are attributable to their terpenoid, aldehyde, and phenolic constituents (Hilbig et al, ; Hyldgaard, Mygind, & Meyer, ). However, their hydrophobic properties cause challenges in incorporating them into aqueous‐based formulation.…”

The use of Brazilian vegetable oils in nanoemulsions: an update on preparation and biological applications

“…In vitro antimicrobial activities (Hilbig et al, 2016) Citronella (10%) Hairy Basil (5%) Vetiver (5%)…”

“…VO has been preferred not only due to the concept that it is safe and biocompatible, but mainly because of the diversity of benefits, and the complex composition of fatty acids can exercise under the skin, protecting it against dehydration, solar radiation, inflammation, insect attack, microorganisms, and viruses (Tadros, Kessell, 2004;Bloise, 2003;Oyedeji, Okeke, 2010;Bakkali et. al., 2008;Harris, 2002; Contri et al, 2012;Hilbig et al, 2016). In comparison to mineral oils, vegetable oils exhibit low viscosity and molecular weight, which makes them less occlusive (Silva, Soares, 1996).…”

Synergistic Effect of the Lactoperoxidase System and Cinnamon Essential Oil on Total Flora andSalmonellaGrowth Inhibition in Raw Milk

“…Only a few approaches have been proposed to reduce the amount of essential oils required and reduce sensory effects [32,33]. For this reason, combinations with other compounds may be promising alternatives [34]. One solution involves combining plant extracts with a bioactive protein in the milk.…”