Physical, antioxidant and antimicrobial properties of chitosan films containing Eucalyptus globulus essential oil
Introduction
Biodegradable films made of polysaccharides, proteins and lipids have currently a variety of advantages over synthetic materials, such as biodegradability, edibility, biocompatibility and environmentally friendly properties (Petersen et al., 1999). These films are loaded with many functional ingredients, such as antioxidants, antimicrobial agents, flavors, spices and colorants which improve the functionality of the packaging materials via adding novel or extra functions (Salmieri & Lacroix, 2006).
Chitosan is a linear polysaccharide of randomly distributed β-(1-4)- linked d-glucosamine and N-acetyl-d-glucosamine, it has been recommended due to its biocompatibility, biodegradability and non-toxicity properties (Guldas, Akpinar-Bayizit, Ozcan and Yilmaz-Ersan, 2010). Chitosan with a high degree of deacetylation (>75%) and an important molecular weight have shown the strongest antibacterial effects in aqueous solutions regardless of the type of acid used for solubilization (No, Park, Lee, & Meyers, 2002). However, the acid used for film preparation significantly affects the film properties. Acetic and formic acid–based films have shown the highest tensile strengths followed by the films prepared with lactic, propionic, and citric acids (Begin & Van Calsteren, 1999). Park, Marsh, and Rhim (2002) confirmed that increasing chitosan molecular weight improved the films strength, but did not significantly affect their water and vapor permeability. Furthermore various additives have been examined for their potential in order to modify chitosan films properties, for example the use of glycerol as plasticizer aiming at decreasing their hydrophilicity (Vargas, Albors, Chiralt, & González-Martínez, 2009). In addition, chitosan offers immense advantages as an edible packaging material owing to its good film-forming properties (Kim et al., 2011, Ruiz-Navajas et al., 2013). However, antimicrobial properties may become inconsiderable when chitosan is in a form of insoluble films (Ouattara, Simard, Piette, Begin, & Holley, 2000). There are several natural ingredients, added to edible films, that present antioxidant or antimicrobial properties such as nisin or lysozyme (Pranoto, Rakshit, & Salokhe, 2005), essential oils (Ruiz-Navajas et al., 2013) or fruit extracts (Genskowsky et al., 2015). Essential oils from plant extracts are natural antimicrobial agents; incorporation of essential oil in edible films may not only enhance the films antimicrobial properties but also reduce water-solubility, vapor-permeability and slow lipid oxidation of the product (Ojagh, Rezaei, Razavi, & Hosseini, 2010).
Eucalyptus species are aromatic and medicinal plants belonging to the Myrtle family. The antimicrobial and antioxidant properties of Eucalyptus species essential oil are widely used in pharmaceutical and cosmetic products, flavoring and preservation of several foods. A number of studies have demonstrated the antimicrobial properties of Eucalyptus essential oils against a wide range of microorganisms (Ait-Ouazzou et al., 2011, Santos et al., 2012). These studies, however, are focused on a few Eucalyptus species, especially Eucalyptus globulus (EG) oil, which has been shown to have a wide spectrum of antimicrobial activity (Pereiraa et al., 2014, Vázquez et al., 2008).
The aim of this study was to evaluate chitosan films incorporated with EG essential oil (1%, 2%, 3% and 4% (v/v)), in order to examine their physical properties, their antioxidant activity and the growth inhibition of some bacterial strains to assess the ability of chitosan films containing EG essential oil to enhance food safety.
Section snippets
Chemicals
Chitosan from shrimp shells (≥75%, deacetylated) was purchased from Sigma–Aldrich Chemical Co. All chemicals were of analytical grade and also purchased from Sigma–Aldrich Chemical Co. (St. LouisMo).
Essential oil extraction from E. globulus
Fresh plant leaves were collected; the leaves were subjected to steam distillation using a Clevenger-type apparatus. Briefly, the plant leaves were completely immersed in water and heated to boiling, after which the essential oil was evaporated together with water vapor and finally collected after
Chemical composition of the EG essential oil
The analytical data of major compounds in EG essential oil were identified by GC–MS and the results are shown Table 1 p-Cymene was a predominant component and accounted for 18.18% of the total peak area. The other components were Methyl eugenol (8.83%), 4-Terpinenol (8.45%), s-Methyl 3-methylbutanethioate (7.26%), γ-Terpinene (5.12%), 1,8-cineole (3.16%), spathulenol (2.98%), 1,8-Menthadien-4-ol (2.36%), α-phellandrene epoxide (2.46%), 1,8-Menthadien-4-ol (2.36%), cis-3-Hexenol (1.95%), Thymol
Conclusion
Chitosan is a promising biopolymer for active food packaging. These results showed that chitosan-based films containing EG essential oil could be used as active films due to its law affinity to water and excellent in vitro antimicrobial and antioxidant activities. Incorporation of EG essential oil in films has decrease moisture content, water-solubility and enhanced the antioxidant and antimicrobial properties which are important in food packaging applications. Edible films made from chitosan
Acknowledgments
This work was supported by a grant from Tunisian Ministry of Higher Education and Scientific Research.
References (47)
- et al.
Antibacterial activity of the essential oils from the leaves of Eucalyptus globulus against Escherichia coli and Staphylococcus aureus
Asian Pacific Journal of Tropical Biomedicine
(2012) - et al.
The antimicrobial activity of the essential oil from achillea fragrantissima
Journal of Ethnopharmacology
(1991) - et al.
Antimicrobial films produced from chitosan
International Journal of Biological Macromolecules
(1999) - et al.
Assessment of antibacterial and antioxidant properties of chitosan edible films incorporated with Maqui berry (Aristotelia chilensis)
LWT – Food Science and Technology
(2015) - et al.
Antimicrobial activity against foodborne pathogens of chitosan biopolymer films of different molecular weights
LWT – Food Science and Technology
(2011) - et al.
Characterization of antioxidant chitosan film incorporated with Zataria multiflora Boiss essential oil and grape seed extract
LWT – Food and Science Technology
(2012) - et al.
Antimicrobial activity of chitosans and chitosan oligomers with different molecular weights
International Journal of Food Microbiology
(2002) - et al.
Development and evaluation of a novel biodegradable film made from chitosan and cinnamon essential oil with low affinity toward water
Food Chemistry
(2010) - et al.
Inhibition of surface spoilage bacteria in processed meats by application of antimicrobial films prepared with chitosan
International Journal of Food Microbiology
(2000) - et al.
Potential of bio based materials for food packaging
Trends in Food Science and Technology
(1999)
Enhancing antimicrobial activity of chitosan films by incorporating garlic oil, potassium sorbate and nisin
LWT – Food Science and Technology
In vitro antibacterial and antioxidant properties of chitosan edible films incorporated with Thymus moroderi or Thymus piperella essential oils
Food Control
Antimicrobial activity of polysaccharide films containing essential oils
Food Control
Phenolic composition and antioxidant activity of Eucalyptus grandis, E. urograndis (E. grandis × E. urophylla) and E. maidenii bark extracts
Industrial Crops and Product
Antimicrobial activity of whey protein based edible films incorporated with oregano, rosemary and garlic essential oils
Food Research International
Physical properties and antioxidant activity of an active film from chitosan incorporated with green tea extract
Food Hydrocolloids
Composition, enantiomeric distribution, and antimicrobial activity of Tanacetum argenteum subsp. flabellifolium essential oil
Journal of Pharmaceutical and Biomedical Analysis
Characterization of chitosan-oleic acid composite films
Food Hydrocolloids
Antioxidant activity and phenolic content of chestnut (Castanea sativa) shell and eucalyptus (Eucalyptus globulus) bark extracts
Industrial Crops and Product
Antioxidant properties of pomegranate (Punica granatum L.) bagasses obtained as co-product in the juice extraction
Food Research International
Antioxidant properties of chitosan from crab shells
Carbohydrate Polymers
Physio-mechanical properties of an active chitosan film incorporated with montmorillonite and natural antioxidants extracted from pomegranate rind
Journal of Food Science Technology
Identification of essential oil components by gas chromatography/quadrupole mass spectroscopy
Cited by (303)
Possible plant-based solutions for skin yeast infections
2024, Fungal Biology ReviewsChitosan based coatings and films: A perspective on antimicrobial, antioxidant, and intelligent food packaging
2024, Progress in Organic Coatings“Review of strategic methods for encapsulating essential oils into chitosan nanosystems and their applications”
2024, International Journal of Biological MacromoleculesEffect of apple polyphenols on physicochemical properties of pea starch/pulp cellulose nanofiber composite biodegradable films
2024, International Journal of Biological Macromolecules