Enhancing stability of Eucalyptus citriodora essential oil by solid nanoliposomes encapsulation
Introduction
Eucalyptus, a medicinal plant belongs to Myrtaceae family, symbolizes an important source of essential oil with potent biological activities including antibacterial, antifungal and antiviral properties (Benchaa et al., 2018). Among various species, Eucalyptus citriodora is one of the most cultivated types due to its high economic value. Eucalyptus citriodora essential oil (ECEO), generally extracted from its leaves and used for ornamental, spices, soap, cosmetics and medicinal purposes (Batish et al., 2008; de Araújo-Filho et al., 2018). Moreover, essential oils including ECEO have also been used as herbicidal, insecticidal, antibacterial, anti-helminthic, anti-tumor, as well as in integrated disease management against plant pathogens and mastitis in animals (Luqman et al., 2008; Cui et al., 2018a, 2019). However, diverse industrial applications of ECEO are restricted due to its volatility, decomposability in the presence of air, light and high temperature (Xiao et al., 2010).
In order to overcome these limitations, many novel encapsulation techniques like lipid nanosystem, microcapsule and electrospinning have been developed to improve its stability (Baldim et al., 2019; Lin et al., 2018a; Sáncheznavarro et al., 2011). Liposomes, which are formed by one or multiple lipids bilayers, have been demonstrated that it is an effective system to encapsulate unstable substance like essential oils and release them at the desired time and place (Cui et al., 2016a). However, phospholipids oxidation, leakage of essential oil and aggregation of particles may be occurred during long-term storage of liposomes. The occurrence of these phenomena is due to the fact that liposomes are water-soluble substances (Immordino et al., 2006). Hence, essential oils encapsulated in liposomes must be converted into solid form along with cryoprotectant.
It has been proved that solid liposomes (SLPs) are a novel-embedding technology and exhibited excellent stability, bioavailability and biocompatibility than aqueous liposomes (Baldim et al., 2019). In practice, SLPs are more convenient for storage and transportation. Moreover, β-cyclodextrin, a kind of oligosaccharide with high glass transition temperature, can be employed to protect liposomal membranes during the process of freeze-drying (Chang et al., 2005).
The present study aimed to prepare optimal solid nanoliposomes encapsulated Eucalyptus citriodora essential oil and estimate its stability. The optimal concentration of ECEO in liposomes and the reasonable ratio of β-cyclodextrin to lipid were ascertained by several qualitative and quantitative indexes. In addition, the release rate of ECEO and the storage stability of ECEO-SLPs were also evaluated in terms of practical and effective utilization in industry.
Section snippets
Materials
Eucalyptus citriodora essential oil (ECEO) was purchased from J.E International (Caussols, France). Soy lecithin and cholesterol were bought from Sigma-Aldrich Chemical Co., Ltd (St. Louis, MO, USA). Anhydrous ethanol, polyvinylpyrrolidone (PVP) and β-cyclodextrin were obtained from Sinopharm Chemical Reagent Co., Ltd. (Shanghai, China).
Chemical components of ECEO
The chemical components of ECEO were confirmed by GC–MS (Agilent 6890GC/5973NMSD, NYSE: A, USA). A fused silica capillary Agilent Technology HP-5 ms column(30 m
Chemical components of ECEO
Different chemical components of ECEO were recorded from GC–MS analysis and results were shown in Table 1. Citronellal was identified as the major component of ECEO, which was corresponded to 79.19% of the total amount. In addition, citronellol (5.95%), isopulegol (2.63%), 1,8-cineole (1.59%), dihydrocarveol (0.78%), terpineol (0.44%) and terpinolene (0.39%) were also detected.
Characterization of ECEO liposomes
The results of four characteristic indicators of ECEO liposomes with various concentration of ECEO were presented in
Conclusion
The present study performed a successful encapsulation of Eucalyptus citriodora essential oil in solid liposomes at a concentration of 4.0 mg/mL through the thin film dispersion method combined with freeze-drying process. Meanwhile, β-cyclodextrin was employed as cryoprotectant to prevent loss of essential oil during this process. Subsequently, the suitable ratio of β-cyclodextrin to lipid at 6:1 was further determined by the results of SEM, DSC and phospholipid antioxidant ability of
Acknowledgements
This research project was financially supported by Hunan Science and Technology Major Project (Grant no. 2016NK1001-3), Natural Science Foundation of Jiangsu Province (Grant no. BK20170070), Jiangsu Province Foundation for talents of six key industries (Grant no. NY-013 and JNHB-131), Jiangsu University Research Fund (Grant no. 11JDG050) and the 18th batch of Jiangsu University Students' Research Funded Project (Grant no. 18A405).
References (31)
- et al.
Lippia sidoides essential oil encapsulated in lipid nanosystem as an anti-Candida agent
Ind. Crops Prod.
(2019) - et al.
Eucalyptus essential oil as a natural pesticide
For. Ecol. Manage.
(2008) - et al.
Mechanism of protein stabilization by sugars during freeze-drying and storage: native structure preservation, specific interaction, and/or immobilization in a glassy matrix?
J. Pharm. Sci.
(2005) - et al.
Antimicrobial mechanism of clove oil on Listeria monocytogenes
Food Control
(2018) - et al.
The antibacterial activity of clove oil/chitosan nanoparticles embedded gelatin nanofibers against Escherichia coli O157:H7 biofilms on cucumber
Int. J. Food Microbiol.
(2018) - et al.
Antibacterial mechanism of oregano essential oil
Ind. Crops Prod.
(2019) - et al.
Intelligent release of cinnamon oil from engineered proteoliposome via stimulation of Bacillus cereus protease
Food Control
(2016) - et al.
Anti-listeria effects of chitosan-coated nisin-silica liposome on Cheddar cheese
J. Dairy Sci.
(2016) - et al.
Effects of Eucalyptus citriodora essential oil and its major component, citronellal, on Haemonchus contortus isolates susceptible and resistant to synthetic anthelmintics
Ind. Crops Prod.
(2018) - et al.
Characterization of chrysanthemum essential oil triple-layer liposomes and its application against Campylobacter jejuni on chicken
LWT-Food Sci. Technol.
(2019)
Electrospun thyme essential oil/gelatin nanofibers for active packaging against Campylobacter jejuni in chicken
LWT-Food Sci. Technol.
Improving the stability of thyme essential oil solid liposome by using β-cyclodextrin as a cryoprotectant
Carbohydr. Polym.
Catalytic mechanisms of metmyoglobin on the oxidation of lipids in phospholipid liposome model system
Food Chem.
A novel amperometric method for antioxidant activity determination using DPPH free radical
Bioelectrochemistry
Synthesis and characterization of imine-modified silicas obtained by the reaction of essential oil of Eucalyptus citriodora, 3-aminopropyltriethoxysilane and tetraethylorthosilicate
Vib. Spectrosc.
Cited by (54)
Evaluating the hypolipidemic effect of garlic essential oil encapsulated in a novel double-layer delivery system
2024, Colloids and Surfaces B: BiointerfacesLiposomes encapsulation by pH driven improves the stability, bioaccessibility and bioavailability of urolithin A: A comparative study
2023, International Journal of Biological MacromoleculesPreparation of a novel brain-targeted EGCG liposome and its antioxidative neuroprotection
2023, Journal of Functional FoodsPreparation of polysaccharide-based nanoparticles by chitosan and flaxseed gum polyelectrolyte complexation as carriers for bighead carp (Aristichthys nobilis) peptide delivery
2023, International Journal of Biological MacromoleculesPreparation of a thermosensitive nanofibre membrane for blackberry preservation
2023, Food Chemistry