Using complex coacervation for lysozyme encapsulation by spray-drying

Fabrication of phenolic loaded spray-dried nanoliposomes stabilized by chitosan and whey protein: Digestive stability, transepithelial transport and bioactivity retention of phenolics

Low bioavailability of phenolic compounds (phenolics) results in low in vivo bioactivity, thus their co-encapsulation could enhance potential health benefits. In this study, reconstitutable nanoliposomes loaded with phenolics varying in solubility were fabricated using spray drying after stabilized by chitosan (CH) or whey protein (WP). The physicochemical properties, biocompatibility, digestive fate, and bioactivity retention of phenolics in different forms were investigated. The surface charge of nanoliposomes (NL) shifted from -18.7 mV to positive due to conjugation with cationic CH (53.1 mV) and WP (14 mV) after spray drying while it was -26.6 mV for only spray-dried phenolics (SDP). Encapsulation efficiency of the tested phenolics ranged between 64.7 % and 95.1 %. Simulated gastrointestinal digestion/Caco-2 cell model was used to estimate the digestive fate of the phenolics yielding up to 3-fold higher bioaccessibility for encapsulated phenolics compared to their native form, combined or individually. However, the cellular uptake or transepithelial transport of phenolics did not differ significantly among formulations, except trans-resveratrol in WP-NL. On the contrary, the suppressive effect of phenolics on fatty acid induced hepatocellular lipid accumulation was strongly dependent on the encapsulation method, no activity was retained by SDP. These findings suggested that reconstitutable nanoliposomes can improve the absorption of phenolics by facilitating their bioaccessibility and thermal and/or processing stability during spray drying.

Heteroprotein complex between soy protein isolate and lysozyme: Protein conformation, lysozyme activity, and structural characterization

Heteroprotein complexes are formed by electrostatic interactions of oppositely charged proteins in a purely aqueous environment. Understanding the relationship between their structural and functional properties will contribute to their tailor-made applications. Therefore, this study investigated the protein conformation, assembling structure, and enzyme activity of soy protein isolate/lysozyme (SPI/LYS) complexes at mass ratios of 2:1 (soluble complex) and 1:1.3 (stoichiometric ratio). Electrostatic complexation increased the surface hydrophobicity of complexes. Their surface hydrophobicity decreased with increasing NaCl concentrations and reached the theoretical values at the critical salt concentration of 200 mM NaCl. Electrostatic complexation did not decrease the LYS activity (∼43,000 units/mg). SPI/LYS complexes exhibited flocculated structures in which the two proteins were unevenly distributed; these were typical amorphous complexes. High dilution disassembled these complexes over 5 μm into particles of ∼100 nm, and NaCl reduced the size of these particles. Immobilized water was detected in the complexes formed by particle flocculation.

Formation of lysozyme-caseinate heteroprotein complexes for encapsulation of lysozyme by spray-drying: Effect of mass ratio and temperature

The formation of heteroprotein complexes obtained by the interactions between sodium caseinate (CAS) and lysozyme (LYS) at pH 7 was investigated by using turbidimetric analysis, particle size distribution, and zeta potential at different CAS/LYS ratios. Moreover, isothermal titration calorimetry (ITC) was used to determine the type and magnitude of the energies involved in the CAS/LYS complexation process and evaluated the thermodynamic behavior of their complexation. Results revealed that the structure of CAS/LYS complexes drastically changed when CAS/LYS ratio increased to 1.0 and the structuring stages were characterized by exothermic signals and were controlled by favorable enthalpy changes due to electrostatic interactions between both proteins. In addition, the interaction between two proteins was temperature-dependent and mainly entropy-driven, which was verified by molecular dynamics (MD) simulations, and the hydrophobic interactions and hydrogen bonding were shown to play an important role in CAS/LYS interactions. Furthermore, CAS/LYS complexes showed minimum LYS enzymatic activity at CAS/LYS ratio 1.0. Though spray-drying of CAS/LYS complexes with ratio 1.0, the LYS activity in reconstituted solution was recovered >80 % of initial activity after calcium chloride addition. The present study provides useful information about CAS/LYS complexation and binding processes, which could facilitate their application in antimicrobial edible food packaging.

Bacteriostatic effects of phage F23s1 and its endolysin on Vibrio parahaemolyticus

Vibrio parahaemolyticus is a common foodborne pathogenic bacterium and drug-resistant strains are now widespread. Phages led by drug-resistant V. parahaemolyticus strains are promising means to decrease the pressure on public health. We isolated a V. parahaemolyticus-specific bacteriophage F23s1 that was active at wide ranges of temperature (30-60°C) and pH (4-10). Phage F23s1 exhibited a specific host range; in that, only 13 of the 23 V. parahaemolyticus strains were lysed. F23s1 effectively inhibited the growth of V. parahaemolyticus strain F23 in shrimp at 25°C within 12 h at a multiplicity of infection of 1000. We sequenced the genome of phage F23s1 which comprised a 76,648-bp DNA with 105 open reading frames (ORFs) and identified an endolysin gene ORF52 that was then cloned and successfully expressed in Escherichia coli. The recombinant ORF52 protein significantly decreased OD_600 nm of V. parahaemolyticus F23 from 0.978 to 0.249 when used at 20 µmol/L within 60 min. The endolysin also showed lytic activity against a panel of 23 drug-resistant V. parahaemolyticus and 12 Salmonella strains with a higher lytic ability for V. parahaemolyticus. The phage F23s1 and its endolysin will be useful for preventing and controlling V. parahaemolyticus in food safety.

Antimicrobial properties of lysozyme in meat and meat products: possibilities and challenges

Meat and meat products are highly perishable as they can provide an appropriate environment for microbial growth due to their high water activity and proper pH level. Quality, safety, sensory and nutritional properties of meat products are highly influenced by pathogenic and spoilage microorganisms. To prevent microbial growth, artificial antimicrobials have been used in food matrices, however safety concerns regarding the use of synthetic preservatives is a challenging issue. Additionally, consumer’s trend towards natural mildly processed products with extended shelf life necessitates the identification of alternative additives originating from natural sources of new acceptable and effective antimicrobials. Although the effectiveness of some natural antimicrobial agents has already been reported, still, there is lack of information regarding the possibility of using lysozyme as a preservative in meat and meat products either alone or in combination with other hurdles. In the present review the applications and beneficial effects of applying lysozyme in meat products, considering its limitations such as allergic problems, interactions with food constituents, reducing sensory changes and toxicity due to high required concentrations to prevent spoilage and oxidation in foods will be discussed

Microencapsulation of Natural Food Antimicrobials: Methods and Applications

The global demand for safe and healthy food with minimal synthetic preservatives is continuously increasing. Some natural food antimicrobials with strong antimicrobial activity and low toxicity have been considered as alternatives for current commercial food preservatives. Nonetheless, these natural food antimicrobials are hardly applied directly to food products due to issues such as food flavor or bioavailability. Recent advances in microencapsulation technology have the potential to provide stable systems for these natural antibacterials, which can then be used directly in food matrices. In this review, we focus on the application of encapsulated natural antimicrobial agents, such as essential oils, plant extracts, bacteriocins, etc., as potential food preservatives to extend the shelf-life of food products. The advantages and drawbacks of the mainly used encapsulation methods, such as molecular inclusion, spray drying, coacervation, emulsification, supercritical antisolvent precipitation and liposome and alginate microbeads, are discussed. Meanwhile, the main current applications of encapsulated antimicrobials in various food products, such as meat, dairy and cereal products for controlling microbial growth, are presented.

Spray-drying of casein/pectin bioconjugate microcapsules containing grape (Vitis labrusca) by-product extract

Novel microcapsules containing grape peel by-product extract were obtained. In this pursuit, complex coacervation of casein/pectin bioconjugate and spray-drying were combined. We have investigated the role of the dispersion feed rate (F_R), drying air inlet temperature (I_T) and drying air flow rate (A_R) in the drying yield, microencapsulation efficiency, total polyphenols and anthocyanins contents, antioxidant activity, and morphology of the products. Also, the first-order degradation kinetics of the phytochemicals for both the extract and dried microcapsules was assessed and compared. The loss on the phytochemicals during spray-drying was attenuated in up to 88%, and the I_T was the main factor affecting the particle properties. The polyphenols on the extract interacted with the polymers, influencing the assemble of the bioconjugate and the particle's features. Such microencapsulation strategy enhanced the thermal stability of the phytochemicals and rendered biocompatible and biodegradable products of which the nutraceutical and cosmeceutical application may have potential.

Enhanced antibacterial activity of lysozyme loaded quaternary ammonium chitosan nanoparticles functionalized with cellulose nanocrystals

In this study, cellulose nanocrystals (CNC) as functional cross-linker and Pickering emulsifier was used to stabilize Lysozyme (Lys) encapsulated in quaternary ammonium chitosan nanoparticles (QC NPs) via ionic gelation method. Physicochemical, structural, and antibacterial properties of the CNC stabilized Lys loaded QC NPs were also evaluated. Particle size, particle size distribution, Zeta potential (ZP), and spectroscopic analyses showed the successful encapsulation of Lys. Antibacterial activity of NPs against Staphylococcus aureus and Vibrio parahaemolyticus was investigated on the basis of inhibition zone (IZ), minimum inhibitory concentration (MIC), and minimum bacterial concentration (MBC). MIC and MBC of CNC stabilized Lys loaded HQC NPs against S. aureus were 0.094 and 0.188 while corresponding values for CNC stabilized Lys loaded LQC NPs V. parahaemolyticus were 0.156 and 0.312 mg/mL, respectively. Therefore, CNC stabilized Lys loaded QC NPs have potential implications in the food industry for food preservation and packaging.

Enhanced Antibacterial Activity of CuS-BSA/Lysozyme under Near Infrared Light Irradiation

The synthesis of multifunctional photothermal nanoagents for antibiotic loading and release remains a challenging task in nanomedicine. Herein, we investigated a simple, low-cost strategy for the preparation of CuS-BSA nanoparticles (NPs) loaded with a natural enzyme, lysozyme, as an antibacterial drug model under physiological conditions. The successful development of CuS-BSA NPs was confirmed by various characterization tools such as transmission electron microscopy (TEM), X-ray diffraction (XRD), Raman spectroscopy, and X-ray photoelectron spectroscopy (XPS). Lysozyme loading onto CuS-BSA NPs was evaluated by UV/vis absorption spectroscopy, Fourier-transform infrared spectroscopy (FTIR), zeta potential, and dynamic light scattering measurements. The CuS-BSA/lysozyme nanocomposite was investigated as an effective means for bacterial elimination of B. subtilis (Gram-positive) and E. coli (Gram-negative), owing to the combined photothermal heating performance of CuS-BSA and lysozyme release under 980 nm (0.7 W cm-2) illumination, which enhances the antibiotic action of the enzyme. Besides the photothermal properties, CuS-BSA/lysozyme nanocomposite possesses photodynamic activity induced by NIR illumination, which further improves its bacterial killing efficiency. The biocompatibility of CuS-BSA and CuS-BSA/Lysozyme was elicited in vitro on HeLa and U-87 MG cancer cell lines, and immortalized human hepatocyte (IHH) cell line. Considering these advantages, CuS-BSA NPs can be used as a suitable drug carrier and hold promise to overcome the limitations of traditional antibiotic therapy.

Benzoic acid complexes with Eudragit E100®: New alternative antimicrobial preservatives

Given that the use of some preservatives in cosmetics has been restricted, novel alternative preservatives are needed. The aim of this study was to characterize the physicochemical and antimicrobial properties of two polyelectrolyte complexes (EuB₁₀₀ and EuB₇₅Cl₂₅), which were developed through hot melt extrusion (HME) using benzoic acid (BA) and Eudragit E100. Based on phase diagrams and an experimental statistical design, the solubility of the acid in the polymer and the HME conditions were established. Intermolecular interactions were evaluated through Fourier-transform infrared spectroscopy (FTIR), X-ray photoelectron spectroscopy (XPS), and X-ray powder diffraction (XRPD). Release behavior was determined for the systems. Antibacterial activity and ζ-potential were determined on Escherichia coli. FTIR revealed acid-base interaction, and XPS showed that the percentages of protonated nitrogen N1s were 13.5% for EuB₁₀₀ and 20.3% for EuB₇₅Cl₂₅. The BA released showed a non-Fickian behavior, and a satisfactory antibacterial activity against E. coli was demonstrated at pH 6.9. The complexes modified ζ-potential, destabilizing the membrane functionality of E. coli. These complexes are potential antimicrobial preservatives with a greater spectrum of action, with bactericidal activity against E. coli in a wider pH range than uncomplexed BA, even at pH 6.9.

Microencapsulation of benzalkonium chloride enhanced its antibacterial and antibiofilm activities against Listeria monocytogenes and Escherichia coli

AIMS

In this study, benzalkonium chloride (BAC) microcapsules were developed for surface disinfection purpose and were evaluated against Listeria monocytogenes and Escherichia coli biofilms.

METHODS AND RESULTS

Microcapsules were prepared with two different strategies: uncomplexed BAC-microcapsules (UBM) containing BAC and maltodextrins, and complexed BAC-microcapsules (CBM) containing BAC complexed by pectin and maltodextrins. The minimum inhibitory concentrations (MICs) of free and microencapsulated BAC were investigated against two food pathogens: L. monocytogenes and E. coli. The antibiofilm activities of UBM and CBM against L. monocytogenes and E. coli biofilms formed on stainless steel at 37°C were evaluated and compared to BAC used under its free form. MICs of encapsulated BAC were up to fourfold lower than those of free BAC. The UBM and CBM showed higher antibiofilm effect when compared to the free BAC.

CONCLUSIONS

Overall, results demonstrated that microencapsulation enhanced the antibacterial activity of BAC against L. monocytogenes and E. coli biofilms.

SIGNIFICANCE AND IMPACT OF THE STUDY

The application of such BAC microcapsule-based delivery systems can improve surface disinfection procedures and reduce the required BAC concentrations and the related cytotoxicity of this antimicrobial compound.

The crucial role of a protein corona in determining the aggregation kinetics and colloidal stability of polystyrene nanoplastics

Nanosized plastics are considered as being a class of contaminants of emerging concern. The interaction between nanoplastics and proteins may significantly influence the environmental behavior and fate of nanoplastics. Here, we employed time-resolved dynamic light scattering to explore the aggregation kinetics and stability of polystyrene nanoparticles (PSNPs) exposed to a model globular protein (bovine serum albumin, BSA) in the presence of a number of typical electrolytes (NaCl, CaCl₂, and Na₂SO₄). With the increase of the BSA concentration, the amount of BSA adsorbed on the surface of negatively charged PS-Bare (non-modified) and PS-COOH (carboxyl-modified) increased, resulting in higher dispersibility in comparison to the treatment without BSA. This stabilization effect derived from the protein corona structure was revealed by combining characterization techniques and visualized by transmission electron microscopy. Upon addition of NaCl and CaCl₂, the aggregation of positively charged PS-NH₂ (amino-modified) was inhibited by the BSA addition possibly due to the screening of the attractive patch-charge force and the competition for adsorption of cations between PS-NH₂ and the protein. When Na₂SO₄ was present in the suspension, BSA addition significantly increased PS-NH₂ aggregation rate due to patch-charge attraction and the high performance of SO₄^2- in attaching to particles and charge neutralization. These findings shed light on the interactions between PSNPs and proteins, which were shown to vary with the composition of the surface coatings of PSNPs. The newly gained knowledge will help us to forecast the transport and fate of PSNPs in natural aqueous systems.

Cashew apple pectin as a carrier matrix for mangiferin: Physicochemical characterization, in vitro release and biological evaluation in human neutrophils

In this work, cashew apple pectin (CP) of the species Anacardium occidentale L. was used as an encapsulation matrix for hydrophobic drugs. The model drug chosen was mangiferin (Mf), a glycosylated C-xanthone which has antioxidant properties but low solubility in aqueous medium. CP (1-100 μg mL^-1) was not toxic to human neutrophils and also did not significantly interfere with the pro-inflammatory mechanism of these cells in the concentration range of 12.5 and 100 μg mL^-1. The results are promising because they show that pectin encapsulated mangiferin after spray drying presented an efficiency of 82.02%. The results obtained in the dissolution test, simulating the release of mangiferin in the gastrointestinal tract (pH 1.2, 4.6 and 6.8) and using Franz diffusion cells (pH 7.4), showed that cashew pectin may be a promising vehicle in prolonged drug delivery systems for both oral and dermal applications.

Anti-biofilm activity of dodecyltrimethylammonium chloride microcapsules against Salmonella enterica serovar Enteritidis and Staphylococcus aureus

Dodecyltrimethylammonium chloride (DTAC) was trapped into maltodextrins/pectin spray dried microcapsules to improve its activity against Salmonella enteritidis and Staphylococcus aureus biofilms. Two different microcapsules were prepared: uncomplexed DTAC-microcapsules (UDM), containing DTAC and maltodextrins; and complexed DTAC-microcapsules (CDM) containing DTAC complexed with pectin and maltodextrins. The minimum inhibitory concentrations (MIC) of both free and microencapsulated DTAC were investigated against S. Enteritidis and S. aureus. The MICs of DTAC were significantly lower when encapsulated. CDM treatment resulted in a 2 and 3.2 log reduction in S. aureus and S. Enteritidis biofilm culturable biomass, respectively. Microencapsulation reduced the cytotoxicity of DTAC by up to 32-fold. Free DTAC and CDM targeted the cell membrane resulting in the leakage of the intracellular molecules and subsequent cell death. The development of DTAC microcapsules reduced the amount of DTAC required to maintain the high standards of cleanliness and hygiene required in the food processing industries.

Stabilization and application of spray-dried tannase from Aspergillus fumigatus CAS21 in the presence of different carriers

The Aspergillus fumigatus CAS21 tannase was spray dried with β-cyclodextrin, Capsul® starch, soybean meal, lactose, and maltodextrin as adjuvants. The moisture content and water activity of the products ranged from 5.6 to 11.5% and from 0.249 to 0.448, respectively. The maximal tannase activity was achieved at 40-60 ºC and pH 5.0-6.0 for the powders containing β-cyclodextrin and Capsul® starch, which was stable at 40 ºC and 40-60 ºC for 120 min, respectively. For all the dried products, tannase retained its activity of over 80% for 120 min at pH 5.0 and 6.0. Salts and solvents influenced the activity of the spray-dried tannase. The activity of the spray-dried tannase was maintained when preserved for 1 year at 4 ºC and 28 ºC. Spray-dried tannase reduced the content of tannins and polyphenolic compounds of leather effluent and sorghum flour and catalyzed the transesterification reaction. The spray drying process stabilized the tannase activity, highlighting the potential of dried products for biotechnological applications.

Essential Oils-Loaded Electrospun Biopolymers: A Future Perspective for Active Food Packaging

The growth of global food demand combined with the increased appeal to access different foods from every corner of the globe is forcing the food industry to look for alternative technologies to increase the shelf life. Essential oils (EOs) as naturally occurring functional ingredients have shown great prospects in active food packaging. EOs can inhibit the growth of superficial food pathogens, modify nutritious values without affecting the sensory qualities of food, and prolong the shelf life when used in food packaging as an active ingredient. Since 2016, various reports have demonstrated that combinations of electrospun fibers and encapsulated EOs could offer promising results when used as food packaging. Such electrospun platforms have encapsulated either pure EOs or their complexation with other antibacterial agents to prolong the shelf life of food products through sustained release of active ingredients. This paper presents a comprehensive review of the essential oil-loaded electrospun fibers that have been applied as active food packaging material.

Use of molecular interactions and mesoscopic scale transitions to modulate protein-polysaccharide structures

Mixed protein-polysaccharide structures have found widespread applications in various fields, such as in foods, pharmaceuticals or personal care products. A better understanding and a more precise control over the molecular interactions between the two types of macromolecules leading to an engineering of nanoscale and colloidal building blocks have fueled the design of novel structures with improved functional properties. However, these building blocks often do not constitute the final matrix. Rather, further process operations are used to transform the initially formed structural entities into bulk matrices. Systematic knowledge on the relation between molecular structure design and subsequent mesoscopic scale transitions induced by processing is scarce. This article aims at establishing a connection between these two approaches. Therefore, it reviews not only studies on the underlying molecular interaction phenomena leading to either a segregative or associative phase behavior and nanoscale or colloidal structures, but also looks at the less systematically studied approach of using macroscopic processing operations such as shearing, heating, crosslinking, and concentrating/drying to transform the initially generated structures into bulk matrices. Thereby, a more comprehensive look is taken at the relationship between different influencing factors, namely solvent conditions (i.e. pH, ionic strength), biopolymer characteristics (i.e. type, charge density, mixing ratio, biopolymer concentration), and processing parameters (i.e. temperature, mechanical stresses, pressure) to generate bulk protein-polysaccharide matrices with different morphological features. The need for a combinatorial approach is then demonstrated by reviewing in detail current mixed protein-polysaccharide applications that increasingly make use of this. In the process, open scientific questions that will need to be addressed in the future are highlighted.

What is new in lysozyme research and its application in food industry? A review

Lysozyme, an important bacteriostatic protein, is widely distributed in nature. It is generally believed that the high efficiency of lysozyme in inhibiting gram-positive bacteria is caused by its ability to cleave the β-(1,4)-glycosidic bond between N-acetylmuramic acid and N-acetylglucosamine. In recent years, there has been growing interest in modifying lysozyme via physical or chemical interactions in order to improve its sensitivity against gram-negative bacterial strains. This review addresses some significant techniques, including sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE), infrared (IR) spectra, fluorescence spectroscopy, nuclear magnetic resonance (NMR), UV-vis spectroscopy, circular dichroism (CD) spectra and differential scanning calorimetry (DSC), which can be used to characterize lysozymes and methods that modify lysozymes with carbohydrates to enhance their various physicochemical characteristics. The applications of biomaterials based on lysozymes in different food matrices are also discussed.

Preparation of a balsa-lysozyme eco-friendly dressing and its effect on wound healing

This study aims to prepare an eco-friendly dressing using a balsa derived membrane with lysozyme included for anti-bacterial purposes. The balsa-lysozyme was prepared using delignification (control) and dopamine (group A) methods for mussel-inspired adhesion of 5, 10, 15 and 20 mg ml-1 lysozyme (groups B, C, D and E). Fourier infrared spectra and the contact angle test showed that lysozyme adhered to the membrane. With increasing concentration of lysozyme, the drug-loading rate of balsa-lysozyme increased and the encapsulation efficiency decreased (P < 0.05). The cumulative release percentages after 72 h were 80.7%, 90.6%, 91.4%and 92.3% in groups B, C, D and E, respectively. There was a significant in vitro antibacterial effect against both E. coli and S. aureus. The cytotoxicity of the wood dressing was not detected until day 7. On day 7, the healing rates were 30.7%, 38.3%, 50.7%, 61.2%, 61.9% and 62.4% for the control, A, B, C, D and E group (P < 0.05). Similarly, the lengths of the new epithelium were 631.7 μm, 702.5 μm, 759.4 μm, 825.3 μm, 831.7 μm and 836.6 μm for the control group, A, B, C, and D, E respectively (P < 0.05). Furthermore, PCNA and CD31 expression indicated enhanced cell proliferation and angiogenesis in the C, D and E group (P < 0.05).

Assessing safety and protein interactions of surface-modified iron oxide nanoparticles for potential use in biomedical areas

We have investigated the electrostatic interaction between bare iron oxide nanoparticles (IONPs) or low molecular weight chitosan coated iron oxide nanoparticles (LMWC-IONPs) and hen egg white lysozyme (HEWL) at different pH values using protein-nanoparticle reverse charge parity model. Physicochemical characterization of both IONPs and LMWC-IONPs were carried out using DLS, TEM, FE-SEM, XRD, TGA, XPS and VSM analysis. DLS, TEM and FE-SEM results indicated that both IONPs were monodispersed, with size ranging from 8 to 20nm. The coating of LMWC on IONPs was confirmed using zeta potential, TGA, XRD and XPS measurements. The cytotoxicity of both IONPs and LMWC-IONPs was studied in vitro in A549 human lung alveolar epithelial cells to assess their use in biomedical applications. Furthermore, the interactions between protein-nanoparticles were investigated by UV-visible, fluorescence and circular dichroism spectroscopic techniques. The present study suggests that water soluble LMWC surface modified IONPs are the promising nanomaterials. The safety and biocompatibility of these nanoparticles render them suitable for biomedical applications.

Designing biopolymer microgels to encapsulate, protect and deliver bioactive components: Physicochemical aspects

Biopolymer microgels have considerable potential for their ability to encapsulate, protect, and release bioactive components. Biopolymer microgels are small particles (typically 100nm to 1000μm) whose interior consists of a three-dimensional network of cross-linked biopolymer molecules that traps a considerable amount of solvent. This type of particle is also sometimes referred to as a nanogel, hydrogel bead, biopolymer particles, or microsphere. Biopolymer microgels are typically prepared using a two-step process involving particle formation and particle gelation. This article reviews the major constituents and fabrication methods that can be used to prepare microgels, highlighting their advantages and disadvantages. It then provides an overview of the most important characteristics of microgel particles (such as size, shape, structure, composition, and electrical properties), and describes how these parameters can be manipulated to control the physicochemical properties and functional attributes of microgel suspensions (such as appearance, stability, rheology, and release profiles). Finally, recent examples of the utilization of biopolymer microgels to encapsulate, protect, or release bioactive agents, such as pharmaceuticals, nutraceuticals, enzymes, flavors, and probiotics is given.

Enhancement of the antimicrobial activity of cinnamon essential oil-loaded electrospun nanofilm by the incorporation of lysozyme

The antimicrobial activity of cinnamon essential oil-based electrospun nanofilm is enhanced by the combination of lysozyme.