Preparation and characterization of cinnamon essential oil nanocapsules and comparison of volatile components and antibacterial ability of cinnamon essential oil before and after encapsulation

Janus hydrogel loaded with a CO2-generating chemical reaction system: Construction, characterization, and application in fruit and vegetable preservation

In this study, we inserted a dynamic chemical reaction system that can generate CO2 into Janus hydrogel (JH) to develop a multidimensional preservation platform that integrates hygroscopicity, antibacterial activity, and modified atmospheric capacity. The double gel system developed using sodium alginate/trehalose at a 1:1 ratio effectively encapsulated 90% of citric acid. Furthermore, CO2 loss was avoided by separately embedding NaHCO3/cinnamon essential oil and citric acid microcapsules into a gelatin pad to develop JH. Freeze-dried JH exhibited a porous and asymmetric structure, very strongly absorbing moisture, conducting water, and rapidly releasing CO2 and essential oils. Furthermore, when preserving various fruits and vegetables in practical settings, JH provided several preservation effects, including color protection, microbial inhibition, and antioxidant properties. Our study findings broaden the application of JH technology for developing chemical reaction systems, with the resulting JH holding substantial promise for cold chain logistics.

Preparation, structural analysis of alcohol aroma compounds/β-cyclodextrin inclusion complexes and the application in strawberry preservation

The dynamic combination of aromas and cyclodextrins is an important means to achieve their stability and controllability, and accurately revealing their interaction rules is the key to designing and constructing high-quality aroma nanocarriers. In this study, the inclusion mechanism between alcohol aroma compounds with different structures and β-cyclodextrin (β-CD) was studied by combining molecular dynamics simulation and experimental methods. Results showed that the selected alcohol aroma compounds formed inclusion complexes (ICs) with β-CD in a 1:1 ratio, while alcohol aroma compounds containing cyclic structures were more tightly bound to β-CD. Van der Waals forces were the primary forces driving the formation and stabilization of the ICs. Cinnamyl alcohol/β-CD ICs showed the most significant antimicrobial effect and notably prolonged the shelf life of strawberries. This study aimed to provide theoretical support for precisely designing and preparing highly stable flavours and fragrances, as well as expanding their application range.

Fabrication of cinnamon essential oil nanoemulsions with high antibacterial activities via microfluidization

The high volatility and hydrophobicity of cinnamon essential oils (CiEO) limited their practical application. To enhance their stability and antibacterial activity, nanoemulsions encapsulating CiEO were prepared using hydroxypropyl-β-cyclodextrin/lauroyl arginate (HPCD/LAE) inclusion complexes through high-pressure microfluidization (HPM). Effects of HPM parameters on the stability and antibacterial properties of nanoemulsion were investigated. Results revealed that increased processing pressure and cycle numbers were associated with reduced droplet size and greater homogeneity in CiEO distribution. Storage and thermal stability were optimized at 100 MPa and seven cycles. Moreover, the nanoemulsions showed strong synergistic antibacterial against E. coli (19.79 mm) and S. aureus (23.61 mm) compared with LAE (11.52 mm and 12.82 mm, respectively) and CiEO alone (13.26 mm and 17.68 mm, respectively). This study provided new information for constructing CiEO nanoemulsion, which is suitable for use in the food industry.

Preparation and characterization of fennel (Foeniculum vulgare miller) essential oil/hydroxypropyl-β-cyclodextrin inclusion complex and its application for chilled pork preservation

Fennel essential oil (FEO) a natural spice that has versatile biological activities. However, the direct use of FEO is limited due to its water insolubility and poor stability. Chilled pork is prone to spoilage during storage. To solve these problems, this study aimed to prepare an inclusion complex (IC) of FEO with hydroxypropyl-β-cyclodextrin via co-precipitation and apply it to the preservation of chilled pork. Results indicated that the optimal parameters were encapsulating temperature 37 °C, wall-core ratio 14:1 g/mL, stirring speed 600 r/min, and encapsulating time 240 min, obtaining an encapsulation efficiency of 83.75%. The results of scanning electron microscopy, Fourier transform infra-red spectroscopy, and nuclear magnetic resonance demonstrated the successful preparation of IC. The release of FEO from IC was controllable through adjusting the different temperatures and relative humidities. Furthermore, IC effectively delayed the spoilage of chilled pork and extended its shelf life by 6 days at 4 °C.

Microbial load reduction in stored raw beef meat using chitosan/starch-based active packaging films incorporated with cellulose nanofibers and cinnamon essential oil

Food safety is a global concern due to the risk posed by microbial pathogens, toxins and food deterioration. Hence, materials with antibacterial and antioxidant properties have been widely studied for their packaging application to ensure food safety. The current study has been designed to fabricate the chitosan/starch-based film with cinnamon essential oil (CEO) and cellulose nanofibers for active packaging. The nanocomposite films developed in this study were characterized by using UV-Vis Spectroscopy, Fourier Transform Infrared Spectroscopy (FTIR), Thermogravimetric analysis (TGA), Scanning Electron Microscopy (SEM), and Gas Chromatography-Mass Spectroscopy (GC-MS). The biodegradability, hydrodynamic, mechanical, antioxidant and antibacterial properties of the films were also evaluated. From the results, the addition of CEO and cellulose nanofibers was found to enhance the antimicrobial and material properties of the film. FE-SEM analysis has also revealed a rough and porous surface morphology for the developed nanocomposite film. FT-IR analysis further demonstrated the molecular interactions among the various components used for the preparation of the film. The film has also been shown to have antibacterial activity against Staphylococcus aureus and Escherichia coli. Furthermore, the film was found to reduce the bacterial load of the stored beef meat when used as a packaging material. The study hence provides valuable insights into the development of chitosan/starch-based films incorporated with CEO and cellulose nanofibers for active food packaging applications. This is due to its excellent antimicrobial and physicochemical properties. Hence, the nanocomposite film developed in the study can be considered to have promising applications in the food packaging industry.

Fabrication and characterization of Karaya gum-based films reinforced with bacterial nanocellulose stabilized valerian root extract Pickering emulsion for lamb meat preservation

A novel biodegradable film was fabricated by incorporating bacterial nanocellulose stabilized valerian root extract (VRE) Pickering emulsion into karaya gum with better antioxidant and antibacterial properties for lamb meat preservation. The valerian root extract Pickering emulsion (VPE) exhibited 98 ± 1.84 % encapsulating efficiency and excellent physical stability with an average particle size of 274.6 nm. The incorporation of VPE-5 into the film matrix increased its elongation at break (EAB), and improved water resistance and barrier properties against oxygen, water vapor, and UV light. Moreover, the antioxidant and anti-bacterial properties against S.aerous and E. coli were also improved based on VPE-5 concentration. The SEM images showed a uniform distribution of VPE-5 while FTIR and XRD revealed its compatibility with karaya gum, which improved its thermal stability. The active films showed a significant preservative effect by reducing the pH, total volatile basic nitrogen (TVB-N), thiobarbituric acid reactive substances (TBARS), and total viable count (TVC) value of lamb meat and maintained its texture and color during the storage period of 9 days at 4 °C. These results demonstrated the inclusion of VPE-5 into Karaya gum was a promising technique and offers a great potential application as a bioactive material in food packaging.

Encapsulation of roast beef flavor by soy protein isolate/chitosan complex Pickering emulsions to improve its releasing properties during the processing of plant-based meat analogues

During the production of plant-based meat analogues (PBMA), a significant loss of flavor characteristic compounds in meat-flavor essences could be observed. Pickering emulsion-based encapsulation is an effective method to improve their stability. Therefore, a soy protein isolate (SPI)/chitosan (CS) complex Pickering emulsion was fabricated to encapsulate roast beef flavor (RBF) and further applied in the processing of PBMA. Our results indicated that the network structure of emulsions was dominated by elasticity, while hydrogen and covalent bonding interactions played important roles in the encapsulation process. The release rate of flavor compounds gradually increased with the increase of pH value, glutamine transaminase, NaCl content, heating temperature or heating time, while encapsulation significantly reduced the loss of characteristic aroma compounds. In addition, the releasing characteristics of aroma compounds and textural properties of PBMA were greatly improved by treating with RBF-loaded emulsions. Consequently, the emulsions were promising to improve the flavor quality of PBMA.

Antimicrobial guar gum films optimized with Pickering emulsions of zein-gum arabic nanoparticle-stabilized composite essential oil for food preservation

In this study, composite essential oil Pickering emulsion stabilized with zein-gum arabic (GA) nanoparticles (ZGCEO) was prepared to improve the characteristics of guar gum (GG) films. ZGCEO exhibited commendable stability and compatibility with GG, while leading to a noticeable improvement in the light barrier (from 3.98 A mm-1 to 17.09 A mm-1) and water vapor barrier characteristics of GG films, concomitantly mitigating their hydrophilic nature, with decreasing moisture content (from 17.70 % to 10.50 %), water solubility (from 84.41 % to 71.79 %), water vapor permeability (from 5.64 × 10-11 g (m s Pa)-1 to 4.97 × 10-11 g (m s Pa)-1), and an increasing water contact angle (from 69.8° to 94.2°). The addition of 2 % ZGCEO yielded a notable increase in the tensile strength of the GG-ZGCEO films, but the elongation at break decreased with increasing ZGCEO concentration. Moreover, the incorporated ZGCEO demonstrated outstanding antioxidant and antimicrobial characteristics, featuring a slow-release behavior of essential oil. The GG-ZGCEO coating also showed an excellent preservation effect in pork and "Huangguan" pears during storage. Collectively, we substantiated the efficacy of ZGCEO in augmenting the functional attributes of GG films, thereby establishing their potential utility as antimicrobial packaging materials conducive to food preservation.

Enhanced repellent and anti-nutritional activities of polymeric nanoparticles containing essential oils against red flour beetle, Tribolium castaneum

Encapsulation of essential oils (EOs) is an important strategy that can be applied to intensify the stability and efficiency of these compounds in integrated pest management. The present study aimed to investigate the sub-lethal activity of polymer-based EOs nanoparticles against red flour beetle, Tribolium castaneum adults as an important critical pest of stored products. Chitosan nanoparticles (CSNPs) containing garlic and cinnamon essential oils (GEO and CEO) prepared using the ionic cross-link technique. Stability of nano-formulations evaluated over temperature and storage time. The fumigant effect (LC10, LC20, LC30) and contact toxicity (LC10, LC15, LC25) determined. In addition, the contact toxicities of EOs and their nanoparticles on nutritional indices evaluated. An olfactometer used to assess the repellent activity of EOs and EOs loaded in CSNPs (EOs@CSNPs) in sub-lethal fumigant concentrations. Characterization results showed GEO loaded in CSNPs has particle size of 231.14 ± 7.55 nm, polydispersity index (PDI) value of 0.15 ± 0.02, encapsulation efficiency (EE) percentage of 76.77 ± 0.20 and zeta potential of - 18.82 ± 0.90 mV, in which these values for the CEO loaded in CSNPs (CEO@CSNPs) changed to 303.46 ± 0.00 nm, 0.20 ± 0.05, 86.81 ± 0.00% and - 20.16 ± 0.35 mV, respectively. A lower PDI value for both CSNPs showed an appropriate NPs size distribution. Furthermore, NPs size and encapsulation efficiency did not change in various temperatures and during four months which confirm good stability of the EOs@CSNPs. In LC30 of GEO@CSNPs, the maximum repellency was determined as 66.66 ± 3.33. Among nutritional indices, in LC25 of GEO@CSNPs, the relative growth rate (RGR) (0.011 ± 0.003 mg.mg-1.day-1), relative consumption rate (RCR) (0.075 ± 0.004 mg.mg-1.day-1) and feeding deterrence index (FDI) (54.662 ± 1.616%) were more affected, so GEO@CSNPs was more effective than CEO@CSNPs. The results of repellent and anti-dietary activities of EOs and EOs@CSNPs confirmed the higher repellency and adverse effectivity on nutritional indices of Tribolium castaneum pest treated with EOs@CSNPs compared to free EOs. In conclusion, the NPs form of GEO and CEO can be a novel and efficient carrier for improving the repellent and anti-nutritional activities of EOs.

Spicing Up Meat Preservation: Cinnamomum zeylanicum Essential Oil in Meat-Based Functional Foods-A Five-Year Review

Today, in the modern consumer era, we are facing a significant change in terms of preferences and behaviour. This tendency is not only a basic desire, but rather a significant social and cultural movement that exerts a tremendous influence on the food industry and correlated sectors. In this direction, food authorities and experts have thoroughly evaluated the practicality of employing natural preservation methods to enhance the quality and safety of foodstuffs, while preserving their nutritional and sensory attributes. Given this context, the development of meat products enhanced with Cinnamomum zeylanicum essential oil (CZEO) poses promising avenues, such as extended shelf-life due to its antimicrobial, antifungal, and antioxidant properties. CZEO also has many health benefits, rendering it as a promising ingredient in functional meat product formulations. Conversely, challenges such as higher associated costs, sensory interactions, and variability arise. Hence, the aim of this review is to offer a novel critical perspective on CZEO's potential application as a functional ingredient in meat products formulations and to address the inherent associated challenges, based on the last five years of scholarly publications.

A starch/gelatin-based Halochromic film with black currant anthocyanin and Nanocellulose-stabilized cinnamon essential oil Pickering emulsion: Towards real-time Salmon freshness assessment

Neoterically, food packaging systems designed solely for prolonging shelf life or monitoring freshness could not fulfil the dynamic demands of consumers. In this current investigation, using the solvent casting method, a versatile halochromic indicator was created by integrating black currant anthocyanin and cinnamon essential oil-loaded Pickering emulsion into a starch/gelatin matrix. The resulting indicator film underwent scrutiny for its structural, pH-sensitive, antioxidant, and antimicrobial attributes. Unexpectedly, the amalgamation of anthocyanin and essential oil led to decreased antioxidant activity, dropping from 73.23 ± 2.17 to 28.87 ± 2.50 mg Trolox equivalent/g sample. Additionally, no discernible antimicrobial properties were detected in the composite film sample against both Staphylococcus aureus and Escherichia coli. Fourier transform infrared analyses unveiled robust intermolecular interactions among the film-forming components, providing insights into the observed antagonistic effect. The indicator film displayed distinctive colour changes corresponding to the fresh (greyish-brown), onset of decomposition (khaki), and spoiled (dark green) stages of the stored fish sample. This highlights its promising potential for providing real-time indications of food spoilage. These findings are important for the efficient design of composite films incorporating anthocyanins and essential oils. They serve as a guide towards their potential use as multifunctional packaging materials in the food industry.

Improving the performance of kraft paper by cinnamon essential oil/soybean protein isolate microcapsules and konjac glucomannan for citrus preservation

In order to reduce the quality loss of citrus and extend its storage time after harvest, it is essential to develop coated kraft papers with antibacterial and fresh-keeping properties. In this study, cinnamon essential oil (CEO)/soybean protein isolate (SPI) microcapsules were prepared by the coagulation method, and their properties were optimized. Then, the microcapsules were added to konjac glucomannan (KGM) as a coating solution to enhance the physical, and chemical properties of kraft paper by a coating method. The release behavior of CEO, tensile properties, antibacterial properties and preservation effects of the paper were investigated. The results show that when the ratio of wall to core was 7:3, the highest encapsulation rate was 92.20 ± 0.43 %. The coating treatment significantly reduced the oxygen and water vapor transmission rates of kraft paper. The shelf life of citrus treated with coated Kraft was extended by >10 days. Thus, the CEO/SPI microencapsulation and KGM coating could improve the properties of kraft paper and have the potential for citrus preservation.

Optimization of Production Parameters for Fabrication of Gum Arabic/Whey Protein-Based Walnut Oil Loaded Nanoparticles and Their Characterization

The encapsulation of fatty acids, including walnut oil, within complexes is a promising strategy to address challenges, for instance, low water solubility and susceptibility to oxidation while incorporating these oils into food products. Additionally, encapsulation can effectively mask undesirable odor and flavor. The current study focuses on the optimization of walnut oil nanoparticles (WON) using complexes fabricated from gum arabic and whey protein by applying a response surface methodology. The impact of three different independent variables were determined, such as surfactant mixture (33-66%), walnut oil (5-25%), and sonication time (60-300 s), under three distinct desired conditions (low, medium, and high) on four different responses, i.e., particle size, polydispersity index (PDI), moisture level, and encapsulation efficiency (EE). The findings of the present study indicate that the point prediction-based WON resulted in significantly low particle size (82.94 nm), PDI (0.19), moisture content (3.49%), and high EE (77.26%). Fourier transform infrared spectroscopy (FTIR) study demonstrated the successful encapsulation of walnut oil and wall material into nanocapsules. Differential scanning calorimetry (DSC) verified the improved thermal stability property of WON after incorporation, and scanning electron microscopy (SEM) indicated that the WON had relatively fragile and smooth surfaces, along with the presence of few porous structures. The recorded experimental data from the existing study showed that the developed formulation of WON was potentially useful as a value-added ingredient for food industries.

Fabrication and characterization of emulsion-based edible film containing cinnamon essential oil using chia seed mucilage

Chia seed mucilage (CSM) film incorporated with 2, 4, and 6 % (w/w) nanoemulsion of cinnamon essential oil (CSM-2, CSM-4, CSM-6) were developed, and their physicochemical, mechanical, antioxidant, and antimicrobial properties were determined. According to the results, cinnamon EO nanoemulsion (CEN) had droplet size 196.07 ± 1.39 nm with PDI 0.47 ± 0.04. Moreover, CSM film had higher water solubility (99.37 ± 0.05 %) and WVP (8.55 ± 1.10 g/kPa h m2) than reinforced CSM films with CENCEN. The lowest water solubility (98.02 ± 0.01 %) and WVP (3.75 ± 0.80 g/kPa h m2) was observed in CSM-6 film. Moreover, the addition of CEN improved the homogeneity and density of films and the smoothness of the surface, being observed by scanning electron microscopy (SEM) and atomic force microscopy (AFM). The Fourier transform infrared (FTIR) spectroscopy also confirmed the incorporation of CEN within the film matrix. The CSM films' antioxidant (DPPH radical scavenging power) and antimicrobial (against Escherichia coli and Staphylococcus aureus) properties of CSM films were notably enhanced with the inclusion of CEN in a dose-dependent manner. The mechanical (tensile strength and elongation at break) of CSM films also was affected by the addition of CEN, TS decreased, and EAB increased (p < 0.05). The lowest TS (20.63 ± 1.39 MPa) and highest EAB (3.36 ± 0.61 %) was observed in CSM-4 film. However, CSM film was relatively dark with low opacity, and adding CEN slightly increased lightness (L*) and yellowness (b*) parameters. The superior antioxidant and barrier characteristics of the CSM edible film incorporated with CEN make it a potential candidate for product packaging and shelf-life extension.

Synthesis and characterisation of Mānuka and rosemary oil-based nano-entities and their application in meat

Mānuka (MO) and rosemary oils (RO) -containing nanoemulsions and nanocapsules made of sodium alginate and whey protein, were designed and compared for their antioxidant effect. Mānuka oil-nanoemulsions and nanocapsules had smaller particle sizes (343 and 330 nm), less negative zeta potential (-12 mV and -10 mV), higher phenolic content, and antiradical characteristics than RO-nano-entities. However, nano-entities of both oils showed more thermostability and sustained release than free oils. Further, the antioxidant effect of essential oils and their nano-entities was compared against sodium nitrite (SN)-added and without antioxidants-added (controls) and Wagyu and crossbred beef pastes (14 days refrigerated storage). No significant difference among MO, RO and their nano-entities was noticed in crossbred pastes, while in Wagyu, nanoemulsions showed the lowest oxidation values than controls and SN-added pastes. Hence, nano-entities can be alternatives to chemical preservatives as natural antioxidants in meat preservation, along with improved thermal stability and release than free oils.

Identification and characterization of major bioactive compounds from Andrographis paniculata (Burm. f.) extracts showed multi-biomedical applications

The Andrographis paniculata recognized as most valuable medicinal plant in folk medicine. Hence, this research was designed to evaluate antibacterial potential of petroleum ether (PE) and methanol (ME) extracts of A. paniculata against skin infection causing bacterial pathogens such as Staphylococcus aureus, Streptococcus pyogenes, Klebsiella pneumoniae, Enterobacter aerogenes, Proteus vulgaris, and Propionibacterium acnes. Also assessed the antidiabetic (α-glucosidase and α-amylase inhibition assay), antioxidant, and photoprotective potential of PE and ME extract analyses. The major bioactive compounds were identified and characterized through UV, FTIR, 1H-NMR and 13C-NMR spectra analyses. The ME extract contain more number of phytochemicals (alkaloids, flavonoids, saponins, terpenoids, glycoside, protein, and phytosterol) than PE extract. The antibacterial activity result also revealed that the ME (as dose dependent) extract showed better activity at 250 mg mL-1 as in the following order: P. acnes (6-29 mm) > K. pneumoniae (3-28 mm) > S. aureus (3-27 mm) > P. vulgaris (3-26 mm) > S. pyogenes (2-25 mm) > E. aerogenes (1-23 mm). PE: E. aerogenes (3-20 mm) > P. vulgaris (2-19 mm) > P. acnes (3-18 mm) > K. pneumoniae (3-17 mm) > S. aureus (2-16 mm) > S. pyogenes (0-11 mm). The MIC value of ME extract was found as 100-150 mg mL-1 and it was better than PE extract. Similarly, the ME also possesses dose based α-glucosidase inhibition activity as up to 85% at 250 mg mL-1 concentration. The fluorescence spectra analysis method also stated that the ME extract possess photoprotective bioactive agent. The ME fractions (F01 and F02) obtained from TLC and column chromatogram were identified as 3-O-β-d-glucosyl-14- deoxyandrographiside and 14-deoxyandrographolide respectively through UV, FTIR, 1H-NMR and 13C-NMR spectra analyses. Such compounds may be responsible for significant antibacterial activity against pathogenic bacteria causing skin infections, excellent antidiabetic activity, as well as photoprotective potential.

Development of Active Antibacterial CEO/CS@PLA Nonwovens and the Application on Food Preservation

The biodegradable activity antibacterial materials have been widely applied on food preservation because they not only protect foods from pathogenic attacks but also relieve environmental pollution. Biodegradable melt-blown nonwovens (MB) have several advantages over the other materials in terms of a simpler and more environmentally friendly fabrication process, higher specific surface area, and lower cost. Herein, polylactic acid (PLA) MB is first modified by polydopamine (PDA) to activate the surface. Then, chitosan (CS) and cinnamon essential oil (CEO) are used to decorate the surface of the modified PLA MB via a simple one-pot method to prepare CEO/CS@PLA MB with different CEO contents. Compared with PLA MB, CEO/CS@PLA MB had a rougher surface and larger average fiber diameter, while the average pore diameter and air permeability reduced. The input of CEO led to a decrease in the tensile strength of CEO/CS@PLA MB and an obvious increase in the elongation at break. The combination of CS and CEO shows excellent synergistic antibacterial effect. The antibacterial efficiencies of CEO/CS@PLA MB against Escherichia coli and Staphylococcus aureus enhance with the increase of the CEO content. When the weight ratio of CS to CEO is 1:2, the antibacterial efficiencies of CEO2/CS@PLA MB against E. coli and S. aureus are 99.98 and 99.99%, respectively. When being applied to the preservation of fresh strawberry, CEO2/CS@PLA MB can effectively inhibit the microbial growth in strawberry and reduce decay, which extends the shelf time of strawberry.

Itaconic acid and dimethyl itaconate exert antibacterial activity in carbon-enriched environments through the TCA cycle

Itaconic acid (IA), a metabolite generated by the tricarboxylic acid (TCA) cycle in eukaryotic immune cells, and its derivative dimethyl itaconate (DI) exert antibacterial functions in intracellular environments. Previous studies suggested that IA and DI only inhibit bacterial growth in carbon-limited environments; however, whether IA and DI maintain antibacterial activity in carbon-enriched environments remains unknown. Here, IA and DI inhibited the bacteria with minimum inhibitory concentrations of 24.02 mM and 39.52 mM, respectively, in a carbon-enriched environment. The reduced bacterial pathogenicity was reflected in cell membrane integrity, motility, biofilm formation, AI-2/luxS, and virulence. Mechanistically, succinate dehydrogenase (SDH) activity and fumaric acid levels decreased in the IA and DI treatments, while isocitrate lyase (ICL) activity was upregulated. Inhibited TCA circulation was also observed through untargeted metabolomics. In addition, energy-related aspartate metabolism and lysine degradation were suppressed. In summary, these results indicated that IA and DI reduced bacterial pathogenicity while exerting antibacterial functions by inhibiting TCA circulation. This study enriches knowledge on the inhibition of bacteria by IA and DI in a carbon-mixed environment, suggesting an alternative method for treating bacterial infections by immune metabolites.

Alginate-based edible coating with oregano essential oil/β-cyclodextrin inclusion complex for chicken breast preservation

A sodium alginate (SA) edible coating containing oregano essential oil (OEO)/β-cyclodextrin (β-CD) inclusion complexes (SA/OEO-MP coating) was developed to extend the shelf life of fresh chicken breast during refrigeration storage. First, OEO was inserted into the hydrophobic interior of β-CD to form an inclusion complex (OEO-MP) that maintained its excellent antioxidant and antibacterial activities. The formed OEO-MP was characterized using fourier transform infrared spectroscopy (FTIR), X-ray diffraction (XRD), and scanning electron microscopy (SEM). In addition, thermogravimetric analysis (TGA) and differential scanning calorimetry (DSC) results demonstrated that β-CD could improve the thermal stability of OEO. The encapsulation efficiency reached 71.6 %, and OEO was released continuously from the OEO-MP. The lipid oxidation, total viable count (TVC) and sensory properties of chicken breasts were regularly monitored when OEO-MP was incorporated into the SA coating for chicken breast preservation. Compared with the uncoated group, the SA/OEO-MP-coated groups showed significantly reduced increases in pH, thiobarbituric acid reactive substances (TBARS), total volatile base nitrogen (TVB-N), and TVC, especially in the SA/OEO-MP1 group. In summary, the SA/OEO-MP coating could preserve the chicken breast by reducing lipid oxidation and inhibiting the proliferation of microorganisms. It would be developed as a prospective edible packaging for chicken preservation.

Nanosizing of Lavender, Basil, and Clove Essential Oils into Microemulsions for Enhanced Antioxidant Potential and Antibacterial and Antibiofilm Activities

Plant essential oils (EOs) possess significant bioactivities (antibacterial and antioxidant) and can be substituted for potentially harmful synthetic preservatives in the food industry. However, limited water solubility, bioavailability, volatility, and stability limit their use. Therefore, the goal of this research was nanosizing lavender essential oil (LEO), basil essential oil (BEO), and clove essential oil (CEO) in a microemulsion (ME) to improve their physicochemical attributes and bioefficacy. Tween 80 and Transcutol P were utilized for construction of pseudoternary phase diagrams. It was observed that the concentration of EOs had a great impact on the physicochemical and biological properties of MEs. A spherical droplet of MEs with a diameter of less than 20 nm with a narrower size distribution (polydispersity index (PDI) = 0.10-0.27) and a ζ potential of -0.27 to -9.03 was observed. ME formulations were also evaluated for viscosity, conductivity, and the refractive index. Moreover, the impact of delivery systems on the antibacterial property of EOs was assessed by determining the zone of inhibition and minimum inhibitory concentration against two distinct pathogen classes (S. aureus and E. coli). Crystal violet assay was used to measure the growth and development of biofilms. According to bioefficacy assays, ME demonstrated more efficient antibacterial activity against microorganisms at concentrations lower than pure EOs. CEO ME had superior activity againstS. aureus and E. coli. Similarly, dose-dependent antioxidant capacity was noted for MEs. Consequently, nanosized EO formulations with improved physicochemical properties and enhanced bioactivities can be employed in the food processing sector as a preservation agent.

Clove essential oil loaded chitosan nanocapsules on quality and shelf-life of blueberries

In this study, the formation of clove essential oil loaded chitosan nanocapsules (CEO/CS-NCs) was achieved by the ionotropic gelation technology. The spherical shape and core-shell structure of CEO/CS-NCs were characterized by SEM, TEM, and FT-IR. CEO/CS-NCs have a reasonable encapsulation efficiency rate of 39 % and an average size of 253.63 nm. The simulated release of CEO/CS-NCs in a citric acid buffer solution shows that the nano-encapsulation technology could control the sustained release of clove essential oil (CEO). The shelf life of untreated blueberries at room temperature is only about 3 days, while CEO/CS-NCs combined with low-temperature storage can extend the shelf life to about 12 days. The quality characteristic of blueberries, including fruit firmness and moisture content, were effectively maintained, and the rotting rate of blueberries was significantly reduced with CEO/CS-NCs. As a natural preservative, CEO/CS-NCs have a good antioxidant activity close to the commercial antioxidant butylated hydroxytoluene (BHT) and a high antibacterial activity against pathogenic bacteria (PB) isolated from naturally occurring blueberries. Therefore, this study not only gives a theoretical basis for the development of CEO as a commercial preservative but also provides a practical solution to solve the protection challenge of preserving blueberries.

Encapsulation and delivery systems of cinnamon essential oil for food preservation applications

Food safety threats and deterioration due to the invasion of microorganisms has led to economic losses and food-borne diseases in the food industry; so, development of natural food preservatives is urgently needed when considering the safety of chemically synthesized preservatives. Because of its outstanding antioxidant and antibacterial properties, cinnamon essential oil (CEO) is considered a promising natural preservative. However, CEO's low solubility and easy degradability limits its application in food products. Therefore, some encapsulation and delivery systems have been developed to improve CEO efficiency in food preservation applications. This work discusses the chemical and techno-functional properties of CEO, including its key components and antioxidant/antibacterial properties, and summarizes recent developments on encapsulation and delivery systems for CEO in food preservation applications. Since CEO is currently added to most biopolymeric films/coatings (BFCs) for food preservation, most studies have shown that encapsulation systems can improve the food preservation performance of BFCs containing CEOs. It has been confirmed that various delivery systems could improve the stability and controlled-release properties of CEO, thereby enhancing its ability to extend the shelf life of foods. These encapsulation techniques include spray drying, emulsion systems, complex coacervation (nanoprecipitation), ionic gelation, liposomes, inclusion complexation (cyclodextrins, silica), and electrospinning.

Anti-Candida and Anti-Leishmanial Activities of Encapsulated Cinnamomum verum Essential Oil in Chitosan Nanoparticles

Nanoencapsulation is widely considered as a highly effective strategy to enhance essential oils' (EO) stability by protecting them from oxidative deterioration and evaporation. The present study aims to optimize and characterize an efficient technique for encapsulating Cinnamomum (C.) verum essential oil into chitosan nanoparticles using response surface methodology (RSM). Moreover, the optimized C. verum EO nanoparticle was investigated for its antibacterial (against Gram-positive and Gram-negative bacteria), antifungal (against Candida albicans), and antiparasitic activity (against Leishmania parasites). Five parameters were investigated using a Plackett-Burman and Box-Behnken statistical design: the chitosan molecular weight, TPP concentration, C. verum EO/chitosan ratio, mixing method, and the duration of the reaction. Encapsulation efficiency and anti-candida activity were considered as responses. The antibacterial, anticandidal, and anti-leishmanial activities were also assessed using a standard micro-broth dilution assay and the cytotoxicity assay was assessed against the macrophage cell line RAW 264.7. The optimized nanoparticles were characterized using Fourier transform infrared spectroscopy, Zeta potential, and scanning electron microscopy. The study results indicated that under optimal conditions, the nanoencapsulation of C. verum EO into chitosan nanoparticles resulted in an encapsulation efficiency of 92.58%, with a regular distribution, a nanoparticle size of 480 ± 14.55 nm, and a favorable Zeta potential of 35.64 ± 1.37 mV. The optimized C. verum EO/chitosan nanoparticles showed strong antifungal activity against C. albicans pathogens (CMI = 125 µg mL-1), notable antibacterial activity against both Gram-positive and Gram-negative bacteria (ranging from 125 to 250 µg mL-1), high leishmanicidal potential against the promastigotes form of L. tropica and L. major (IC50 = 10.47 and 15.09 µg mL-1, respectively), and a four-fold cytotoxicity reduction compared to non-encapsulated essential oil. These results suggest that C. verum EO-loaded chitosan nanoparticles could be a promising delivery system for the treatment of cutaneous Candida albicans infections.

Plant Antimicrobials for Food Quality and Safety: Recent Views and Future Challenges

The increasing demand for natural, safe, and sustainable food preservation methods drove research towards the use of plant antimicrobials as an alternative to synthetic preservatives. This review article comprehensively discussed the potential applications of plant extracts, essential oils, and their compounds as antimicrobial agents in the food industry. The antimicrobial properties of several plant-derived substances against foodborne pathogens and spoilage microorganisms, along with their modes of action, factors affecting their efficacy, and potential negative sensory impacts, were presented. The review highlighted the synergistic or additive effects displayed by combinations of plant antimicrobials, as well as the successful integration of plant extracts with food technologies ensuring an improved hurdle effect, which can enhance food safety and shelf life. The review likewise emphasized the need for further research in fields such as mode of action, optimized formulations, sensory properties, safety assessment, regulatory aspects, eco-friendly production methods, and consumer education. By addressing these gaps, plant antimicrobials can pave the way for more effective, safe, and sustainable food preservation strategies in the future.

The mechanism, biopolymers and active compounds for the production of nanoparticles by anti-solvent precipitation: A review

The anti-solvent precipitation method has been investigated to produce biopolymeric nanoparticles in recent years. Biopolymeric nanoparticles have better water solubility and stability when compared with unmodified biopolymers. This review article focuses on the analysis of the state of the art available in the last ten years about the production mechanism and biopolymer type, as well as the used of these nanomaterials to encapsulate biological compounds, and the potential applications of biopolymeric nanoparticles in food sector. The revised literature revealed the importance to understand the anti-solvent precipitation mechanism since biopolymer and solvent types, as well as anti-solvent and surfactants used, can alter the biopolymeric nanoparticles properties. In general, these nanoparticles have been produced using polysaccharides and proteins as biopolymers, especially starch, chitosan and zein. Finally, it was identified that those biopolymers produced by anti-solvent precipitation were used to stabilize essential oils, plant extracts, pigments, and nutraceutical compounds, promoting their application in functional foods.

Facile modification of nanochitin in aqueous media for stabilizing tea tree oil based Pickering emulsion with prolonged antibacterial performance

Nanochitins have been explored for preparing Pickering Emulsions, however its application is restricted by its simplex disperse nature. It was hypothesized that zwitterionic nanochitins should be capable of stabilizing oil/water (O/W) interfaces in wider pH range. Furthermore, the control of their size, disperse nature and self-assembly performance suggest the formulation of tunable emulsions. Zwitterionic nanochitins were prepared via Schiff base reaction. A systematic study was performed analyzing the disperse nature, fibril morphology, surface characteristic of modified nanochitins. Oil-in-Water Pickering Emulsions stabilized by modified nanochitins were formulated and emulsion stability was analyzed as function of concentration, pH and self-assembly property and further applied for prolonged antibacterial applications. Comparing freshly prepared nanochitins, neutral/alkaline stably dispersed nanochitins can be prepared while maintaining fibril characteristics such as fibril size, crystallinity, thermal stability and so on. Better suspension stability of modified nanochitins under alkaline conditon together with the self assembly performance resulting from amino groups and carboxyl groups benefit the enhanced emulsion stability under nanochitins concentreation of 0.2 %. Encapsulation of tea tree oil in Pickering Emulsions prolongs the diffusion rate oil in the aqueous environment, thus resulting prolongs its antibacterial performance against E. coli and B. subtilis.

Preparation and characterization of inclusion complex of Myristica fragrans Houtt. (nutmeg) essential oil with 2-hydroxypropyl-β-cyclodextrin

Nutmeg essential oil (NEO) is a natural condimentwith versatile biological activities. However, the application of NEO in food has several limitations due to its poor stability and low aqueous solubility. To overcome the shortcomings, this paper focused on the preparation of the inclusion complex (IC) of NEO with 2-hydroxypropyl-β-cyclodextrin (HP-β-CD) by the coprecipitation method. The optimal condition was inclusion temperature 36 ℃, time 247 min, stirring speed 520 r/min, and wall-core ratio 12:1, resulting in a recovery of 80.63%. The formation of IC was verified by various methods such as scanning electron microscopy, Fourier transform infrared spectroscopy and nuclear magnetic resonance. The improvement of thermal stability, antioxidant, and nitrite scavenging activities of NEO after encapsulation was proven. Moreover, the controlled release of NEO from IC can be implemented by regulating the temperature and relative humidity. Overall, NEO/HP-β-CD IC has great application potential in food industries.

Effects of cinnamon essential oil-loaded Pickering emulsion on the structure, properties and application of chayote tuber starch-based composite films

The use of non-conventional starch sources to develop biodegradable and bioactive starch-based films have attracted increasing attention recently. In this study, a nonconventional chayote tuber starch (CTS) was functionalized by zein-pectin nanoparticle-stabilized cinnamon essential oil (CEO) Pickering emulsion (ZPCO) to develop a novel bioactive composite films for food packaging application. Results demonstrated that antibacterial ZPCO featuring long-term stability was successfully obtained. FTIR and SEM analyses suggested that ZPCO have favorable dispersibility and compatibility with CTS matrix. With ZPCO increasing, the transmittance, tensile strength, and moisture content of composite films decreased, whereas their elongation at break, antimicrobial and antioxidant activities increased. ZPCO added at an appropriate level (2 %) can improve water-resistance of the films and reduce water vapor permeability. More importantly, ZPCO can achieve a slower sustained-release of CEO from composite films into food simulants. Furthermore, the composite film containing 2 % ZPCO is safe and nontoxic as proved by cell cytotoxicity test, and it can significantly prolong the shelf life of ground beef by showing the lowest total volatile base nitrogen and best acceptable sensory characteristic. Overall, the incorporation of ZPCO into CTS films offers a great potential application as a bioactive material in the food packing.

Antioxidant and antimicrobial collagen films incorporating Pickering emulsions of cinnamon essential oil for pork preservation

Cinnamon essential oil (CEO)-based Pickering emulsions were prepared using chitosan (CS) and soy protein isolate (SPI) colloid particles as stabilizers and genipin as cross-linker. Pickering emulsions have smaller particle sizes, higher stability, and encapsulation efficiency at a CS:SPI ratio of 1:4. The Pickering emulsion-modified collagen films showed enhanced thermal stability, UV-blocking properties, and water resistance. In addition, the antioxidant (DPPH scavenging activity, 18.35%-50.59%) and antimicrobial activities (inhibition zone, Escherichia coli, 0-1.85 cm; Staphylococcus aureus, 0-1.57 cm; Pseudomonas fluorescens, 0-1.34 cm) of the films were improved due to the sustained release of CEO, with the release kinetics following the Fickian diffusion of the Ritger-Peppas model. When the functionalized film was used for pork preservation, a four-day extension of shelf life was observed. Collectively, our findings suggest that Pickering emulsions provide great potential for the application of collagen film in pork preservation.

Microencapsulation of tomato seed oil using phlorotannins-adducted pea protein isolate-chitosan and pea protein isolate-chitosan complex coacervates

Pea protein isolates (PPI)/phlorotannins (PT)/chitosan (CS) ternary complex and PPI/CS binary complex were synthesized to prepare tomato seed oil (TSO) microcapsules. The concentration of PT was determined to be 0.025% (w/w) based on the solubility, emulsification, and UV-visible spectrum of PPI-PT complex. Subsequently, the optimal pHs associated with the formation of PPI/CS and PPI-PT/CS complex coacervates were determined to be pH 6.6 and 6.1, while the optimal ratios were 9:1 and 6:1, respectively. The coacervate microcapsules were successfully produced by freeze-dried method and those formulated with PPI-PT/CS displayed significantly lower surface oil content (14.57 ± 0.22%), higher encapsulation efficiency (70.54 ± 0.13%), lower particle size (5.97 ± 0.16 μm), and PDI (0.25 ± 0.02) than PPI/CS. The microcapsules were characterized by scanning electron microscopy and Fourier Transform infrared spectroscopy. Furthermore, the encapsulated TSO exhibited enhanced thermal and oxidative stability than that of free oil, along with microcapsules fabricated with PPI-PT/CS ternary complex showed better protection than that of free PT. Overall, PPI-PT/CS complex as an effective wall material in delivery system presented great potential.

Recent Advances in Using Natural Antibacterial Additives in Bioactive Wound Dressings

Wound care is a global health issue with a financial burden of up to US $96.8 billion annually in the USA alone. Chronic non-healing wounds which show delayed and incomplete healing are especially problematic. Although there are more than 3000 dressing types in the wound management market, new developments in more efficient wound dressings will require innovative approaches such as embedding antibacterial additives into wound-dressing materials. The lack of novel antibacterial agents and the misuse of current antibiotics have caused an increase in antimicrobial resistance (AMR) which is estimated to cause 10 million deaths by 2050 worldwide. These ongoing challenges clearly indicate an urgent need for developing new antibacterial additives in wound dressings targeting microbial pathogens. Natural products and their derivatives have long been a significant source of pharmaceuticals against AMR. Scrutinising the data of newly approved drugs has identified plants as one of the biggest and most important sources in the development of novel antibacterial drugs. Some of the plant-based antibacterial additives, such as essential oils and plant extracts, have been previously used in wound dressings; however, there is another source of plant-derived antibacterial additives, i.e., those produced by symbiotic endophytic fungi, that show great potential in wound dressing applications. Endophytes represent a novel, natural, and sustainable source of bioactive compounds for therapeutic applications, including as efficient antibacterial additives for chronic wound dressings. This review examines and appraises recent developments in bioactive wound dressings that incorporate natural products as antibacterial agents as well as advances in endophyte research that show great potential in treating chronic wounds.

Temperature controlled microcapsule loaded with Perilla essential oil and its application in preservation of peaches

In this study, Perilla frutescens essential oil (PEO) loaded microcapsules (PEOM) were successfully prepared and their thermal stability, temperature-responsive releasing effect, antioxidant activity, antibacterial activity, and preservation of peach were systematically investigated. PEOM showed excellent encapsulation efficiency (91.5%) with a core-shell ratio of 1.4:1 and exhibited high thermal stability, indicating that PEOM could effectively maintain PEO release rate. In vitro assays indicated that the optimal kinetic model for PEO release fitted well with first order with a diffusion mechanism. A high level of antioxidant and antibacterial activity of PEOM was maintained. In addition, owing to its sustained release, PEOM could prolong the shelf life of peaches significantly. Therefore, PEOM has potential application and development prospects in the field of food preservation.

Functional insights to the development of bioactive material for combating bacterial infections

The emergence of antibiotic-resistant "superbugs" poses a serious threat to human health. Nanomaterials and cationic polymers have shown unprecedented advantages as effective antimicrobial therapies due to their flexibility and ability to interact with biological macromolecules. They can incorporate a variety of antimicrobial substances, achieving multifunctional effects without easily developing drug resistance. Herein, this article discusses recent advances in cationic polymers and nano-antibacterial materials, including material options, fabrication techniques, structural characteristics, and activity performance, with a focus on their fundamental active elements.

Encapsulation Efficiency and Functional Stability of Cinnamon Essential Oil in Modified β-cyclodextrins: In Vitro and In Silico Evidence

Essential oils (EOs) have good natural antioxidant and antimicrobial properties; however, their volatility, intense aroma, poor aqueous solubility, and chemical instability limit their applications in the food industry. The encapsulation of EOs in β-cyclodextrins (β-CDs) is a widely accepted strategy for enhancing EO applications. The complexation of cinnamon essential oil (CEO) with five types of β-CDs, containing different substituent groups (β-CD with primary hydroxyl, Mal-β-CD with maltosyl, CM-β-CD with carboxymethyl, HP-β-CD with hydroxypropyl, and DM-β-CD with methyl), inclusion process behaviors, volatile components, and antioxidant and antibacterial activities of the solid complexes were studied. The CEOs complexed with Mal-β-CD, CM-β-CD, and β-CD were less soluble than those complexed with DM-β-CD and HP-β-CD. Molecular docking confirmed the insertion of the cinnamaldehyde benzene ring into various β-CD cavities via hydrophobic interactions and hydrogen bonds. GC-MS analysis revealed that HP-β-CD had the greatest adaptability to cinnamaldehyde. The CEO encapsulated in β-, Mal-β-, and CM-β-CD showed lower solubility but better control-release characteristics than those encapsulated in DM- and HP-β-CD, thereby increasing their antioxidant and antibacterial activities. This study demonstrated that β-, Mal-β-, and CM-β-CD were suitable alternatives for the encapsulation of CEO to preserve its antioxidant and antibacterial activities for long-time use.

Microemulsion of Cinnamon Essential Oil Formulated with Tea Polyphenols, Gallic Acid, and Tween 80: Antimicrobial Properties, Stability and Mechanism of Action

The objective of this article was to combine tea polyphenols, gallic acid, and cinnamon essential oil to construct a natural extract-complex microemulsion system (NMs) with good antibacterial activity, antioxidant activity, and stability, as well as low irritation. NMs were characterized by particle size distribution, electrical conductivity, and light transmittance. The stability, as well as the antimicrobial, antioxidant, irritation, and antimicrobial mechanisms, of NMs were also studied. The results showed that NMs had a significant antimicrobial function against Staphylococcus aureus, Escherichia coli, Pseudomonas aeruginosa, Candida albicans and Aspergillus brasiliensis. The minimum inhibitory concentrations were 156 μg/mL, 62.5 μg/mL, 125 μg/mL, 250 μg/mL, and 125 μg/mL, respectively. Through the cell membrane permeability test and growth curve test of bacteria and fungi, we concluded that the NMs' mechanism of action on bacteria and fungi could be interpreted as NMs mainly altering the permeability of cell membranes to inhibit the growth of bacteria and fungi. The results of this study have important implications for utilizing plant extracts as natural preservatives for food and cosmetics.

Preparation and antibacterial and antioxidant ability of β-cyclodextrin complexes of vaporized Illicium verum essential oil

Compared with traditional liquid-liquid embedding method and solid-liquid embedding method of inclusion complexes of β-cyclodextrin (β-CD) inclusion of essential oil to form stable properties, the gas-liquid embedding method was applied to encapsulate vaporized illicium verum essential oil (IvEO), with β-CD as wall materials so that core and wall materials molecules are in active state during complexing process. At optimal conditions with a mass ratio of 1:10, temperature of 80°C, time of 1 h, the β-CD-IvEO inclusion complexes (β-CD-IvEO-ICs) had an encapsulation efficiency (EE) of 84.55 ± 2.31%. Fourier transform infrared spectroscopy (FTIR) revealed the encapsulation of IvEO into inclusion complexes, differential scanning calorimetry (DSC) and thermogravimetric analysis (TGA) demonstrated the enhanced thermal stability of IvEO after embedding. Furthermore, the reducing power and 2-phenyl-4,4,5,5-tetramethylimidazoline-1-oxyl-3-oxide (PTIO)-scavenging capacity displayed certain capacity of antioxidation in a short time but stronger antioxidative activities as reaction time was extended. The diameter of growth zone (DGZ) indicated stronger antibacterial activity of β-CD-IvEO-ICs against Escherichia coli, Bacillus subtilis, Staphylococcus epidermidis, and Staphylococcus aureus. Moreover, the β-CD-IvEO-ICs could induce the bacteria producing more reactive oxygen species (ROS) than IvEO, resulting in bacterial death.

Recent advances in essential oil complex coacervation by efficient physical field technology: A review of enhancing efficient and quality attributes

Although complex coacervation could improve the water solubility, thermal stability, bioavailability, antioxidant activity and antibacterial activity of essential oils (EOs). However, some wall materials (such as proteins and polysaccharides) with water solubility and hydrophobic nature limited their application in complex coacervation. In order to improve the properties of EO complex coacervates, some efficient physical field technology was proposed. This paper summarizes the application and functional properties of EOs in complex coacervates, formation and controlled-release mechanism, as well as functions of EO complex coacervates. In particular, efficient physical field technology as innovative technology, such as high pressure, ultrasound, cold plasma, pulsed electric fields, electrohydrodynamic atomization and microwave technology improved efficient and quality attributes of EO complex coacervates are reviewed. The physical fields could modify the gelling, structural, textural, emulsifying, rheological properties, solubility of wall material (proteins and polysaccharides), which improve the properties of EO complex coacervates. Overall, EOs complex coacervates possess great potential to be used in the food industry, including high bioavailability, excellent antioxidant capacity and gut microbiota in vivo, masking the sensation of off-taste or flavor, favorable antimicrobial capacity.

Inhibitory Effect and Mechanism of Dill Seed Essential Oil on Neofusicoccum parvum in Chinese Chestnut

The chestnut postharvest pathogen Neofusicoccum parvum (N. parvum) is an important postharvest pathogen that causes chestnut rot. Chestnut rot in postharvest reduces food quality and causes huge economic losses. This study aimed to evaluate the inhibitory effect of dill seed essential oil (DSEO) on N. parvum and its mechanism of action. The chemical characterization of DSEO by gas chromatography/mass spectrometry (GC/MS) showed that the main components of DSEO were apiole, carvone, dihydrocarvone, and limonene. DSEO inhibited the growth of mycelium in a dose-dependent manner. The antifungal effects are associated with destroying the fungal cell wall (cytoskeleton) and cell membrane. In addition, DSEO can induce oxidative damage and intracellular redox imbalance to damage cell function. Transcriptomics analysis showed DSEO treatment induced differently expressed genes most related to replication, transcription, translation, and lipid, DNA metabolic process. Furthermore, in vivo experiments showed that DSEO and DSEO emulsion can inhibit the growth of fungi and prolong the storage period of chestnuts. These results suggest that DSEO can be used as a potential antifungal preservative in food storage.

Preparation and characterization of emamectin benzoate nanocapsules based on the dual role of polydopamine

BACKGROUND

Developing pesticide-controlled release formulations with foliage adhesion has become the focus of current research in the field of crop protection. In this study, an excellent adhesive nanocapsule loaded with emamectin benzoate (Eb@PDA) was prepared via emulsion interfacial polymerization based on the self-polymerization ability and adhesion properties of polydopamine (PDA).

RESULTS

The physicochemical properties of the Eb@PDA were characterized by scanning electron microscopy, transmission electron microscopy, particle size statistics, Fourier transform infrared spectroscopy and X-ray diffraction. The Eb@PDA presented a regular spherical shape, with an average particle size of 163.8 nm. Compared with conventional formulations, it had higher pesticide-loading content (34%) and excellent adhesion onto corn leaf. In addition, Eb@PDA showed sustained-release characteristics, facilitating the release of Eb at low pH and high temperature. Eb@PDA could effectively protect Eb against photodegradation and had a longer effective period for controlling Spodoptera frugiperda and Spodoptera exigua. Furthermore, acute toxicity tests showed that the 50% lethal concentration (LC₅₀ ) was 80.91 and 57.91 mg kg^-1 at 7 and 14 days, respectively, indicating a lower toxicity of the Eb@PDA to earthworms. The cells (L02) treated with Eb@PDA showed a higher cell viability but a lower apoptosis rate (only 5.75%), demonstrating the lower cytotoxicity of the Eb@PDA.

CONCLUSION

The self-prepared Eb@PDA could be used as a formulation with the advantages of slow release, UV shielding, strong leaf adhesion, superior insecticidal properties, sustained effectiveness and biosafety. It will also facilitate the development of an efficient and safe pesticide delivery system. © 2022 Society of Chemical Industry.

Formation of cinnamon essential oil/xanthan gum/chitosan composite microcapsules basing on Pickering emulsions

Cinnamon essential oil (CNO) is a natural and renewable antibacterial agent. However, CNO is highly volatile and unstable, which limits its practical application as a long-term and wide antibacterial agent. In order to improve the CNO stability, we have microencapsulated CNO into composite microcapsules basing on Pickering emulsion stabilized by silica (SiO₂) nanoparticles. The CNO-loaded composite microcapsules possess the hybrid microcapsule shell including SiO₂, xanthan gum and chitosan. Moreover, the results show that the microcapsules have spherical appearance. Microencapsulation technique effectively promotes the CNO stability, and the loaded CNO is slowly released from microcapsules. The antibacterial test indicates that the minimal inhibitory concentration of microcapsules was 2 mg mL⁻¹ against Escherichia coli and Staphylococcus aureus, and the microcapsules can play an effective long-term antibacterial effect. Thus, Pickering emulsion templates is a convenient and effective technique to construct antibacterial essential oil-contained microcapsules, which can be used as long-term antibacterial agents.