Microencapsulation of eugenol molecules by β-cyclodextrine as a thermal protection method of antibacterial action

Preparation, characterization, oral bioavailability, and pharmacodynamic study of eugenol-porous silica solidified powder

Eugenol possesses anti-inflammatory and antioxidant properties, and may serve as a potential therapeutic agent for hepatic fibrosis. However, the development of solid eugenol formulations is challenging due to its volatility. To address this issue, this study employed porous silica to adsorb solidified eugenol. The solidified powder was characterized using Fourier transform infrared spectroscopy (FTIR), differential scanning calorimetry (DSC), and scanning electron microscopy (SEM). In addition, the differences in in vitro release and oral bioavailability between eugenol and solidified eugenol powder were investigated. The effectiveness of eugenol and eugenol powder in treating liver fibrosis was investigated using enzyme-linked immunosorbent assay (ELISA), polymerase chain reaction (PCR), and histopathological observations. Our results indicate that porous silica can effectively solidify eugenol into powder at a lower dosage. Furthermore, we observed that porous silica accelerates eugenol release in vitro and in vivo. The pharmacodynamic results indicated that eugenol has a positive therapeutic effect against hepatic fibrosis and that porous silica does not affect its efficacy. In conclusion, porous silica was able to solidify eugenol, which may facilitate the preparation and storage of solid formulations.

Enhanced Stability and Solidification of Volatile Eugenol by Cyclodextrin-Metal Organic Framework for Nasal Powder Delivery

Eugenol (Eug) holds potential as a treatment for bacterial rhinosinusitis by nasal powder drug delivery. To stabilization and solidification of volatile Eug, herein, nasal inhalable γ-cyclodextrin metal-organic framework (γ-CD-MOF) was investigated as a carrier by gas-solid adsorption method. The results showed that the particle size of Eug loaded by γ-CD-MOF (Eug@γ-CD-MOF) distributed in the range of 10-150 μm well. In comparison to γ-CD and β-CD-MOF, γ-CD-MOF has higher thermal stability to Eug. And the intermolecular interactions between Eug and the carriers were verified by characterizations and molecular docking. Based on the bionic human nasal cavity model, Eug@γ-CD-MOF had a high deposition distribution (90.07 ± 1.58%). Compared with free Eug, the retention time Eug@γ-CD-MOF in the nasal cavity was prolonged from 5 min to 60 min. In addition, the cell viability showed that Eug@γ-CD-MOF (Eug content range 3.125-200 µg/mL) was non-cytotoxic. And the encapsulation of γ-CD-MOF could not reduce the bacteriostatic effect of Eug. Therefore, the biocompatible γ-CD-MOF could be a potential and valuable carrier for nasal drug delivery to realize solidification and nasal therapeutic effects of volatile oils.

Lyophilized Emulsions of Thymol and Eugenol Essential Oils Encapsulated in Cellulose

Efforts to tap into the broad antimicrobial, insecticidal, and antioxidant activities of essential oils (EOs) are limited due to their strong odor and susceptibility to light and oxidation. Encapsulation of EOs and subsequent drying overcome these limitations and extend their applications. This study characterized freeze-dried (lyophilized) emulsions of eugenol (EU) and thymol (TY) EOs, encapsulated by chemically unmodified cellulose, a sustainable and low-cost resource. High-resolution scanning electron microscopy showed successful lyophilization. While the observed "flake-like" structure of the powders differed significantly from that of the emulsified microcapsules, useful properties were retained. Fourier transform infrared spectroscopy confirmed the presence of EOs in their corresponding powders and thermo-gravimetric analysis demonstrated high encapsulation efficiency (87-88%), improved thermal stability and resistance to evaporation, and slow EO release rates in comparison to their free forms. The lightweight and low-cost cellulose encapsulation, together with the results showing retained properties of the dried powder, enable the use of EOs in applications requiring high temperatures, such as EO incorporation into polymer films, that can be used to protect agricultural crops from microbial infections.

Advancements in application of chitosan and cyclodextrins in biomedicine and pharmaceutics: recent progress and future trends

The global community is faced with numerous health concerns such as cancer, cardiovascular and neurological diseases, diabetes, joint pain, osteoporosis, among others. With the advancement of research in the fields of materials chemistry and medicine, pharmaceutical technology and biomedical analysis have entered a new stage of development. The utilization of natural oligosaccharides and polysaccharides in pharmaceutical/biomedical studies has gained significant attention. Over the past decade, several studies have shown that chitosan and cyclodextrin have promising biomedical implications in background analysis, ongoing development, and critical applications in biomedical and pharmaceutical research fields. This review introduces different types of saccharides/natural biopolymers such as chitosan and cyclodextrin and discusses their wide-ranging applications in the biomedical/pharmaceutical research area. Recent research advances in pharmaceutics and drug delivery based on cyclodextrin, and their response to smart stimuli, as well as the biological functions of cyclodextrin and chitosan, such as the immunomodulatory effects, antioxidant, and antibacterial properties, have also been discussed, along with their applications in tissue engineering, wound dressing, and drug delivery systems. Finally, the innovative applications of chitosan and cyclodextrin in the pharmaceutical/biomedicine were reviewed, and current challenges, research/technological gaps, and future development opportunities were surveyed.

pH-responsive on-demand release of eugenol from metal-organic frameworks for synergistic bacterial killing

Bacterial infections are a big challenge in clinical treatment, making it urgent to develop innovative antibacterial systems and therapies to combat bacterial infections. In this study, we developed a novel MOF-based synergistic antibacterial system (Eu@B-UiO-66/Zn) by loading a natural antibacterial substance (eugenol) with hierarchically porous MOF B-UiO-66 as a carrier and further complexing it with divalent zinc ions. Results indicate that the system achieved a controlled release of eugenol under pH responsive stimulation, with the complexation ability of eugenol and Zn2+ ions as a switch. Due to the destruction of a coordination bond between eugenol and Zn2+ ions by an acidic medium, the release of eugenol loaded in Eu@B-UiO-66/Zn reached 80% at pH 5.8, which was significantly higher than that under pH 8.0 (51%). Moreover, the inhibitory effect of Eu@B-UiO-66/Zn against Escherichia coli (E. coli) and Staphylococcus aureus (S. aureus) after 24 h was 96.4% and 99.7%, respectively, owing to the synergistic antibacterial effect of eugenol and Zn2+ ions, which was significantly stronger than free eugenol and Eu@B-UiO-66. We hope that this strategy for constructing responsive MOF-based antibacterial carriers could have potential possibilities for the application of MOF materials in antibacterial fields.

Enhancing the targeting performance and prolonging the antibacterial effects of clove essential oil liposomes to Campylobacter jejuni by antibody modification

The application of plant essential oil liposomes to prevent and control food safety risks caused by Campylobacter jejuni (C. jejuni) still faces challenges such as lack of targeting and low release rate. Here, a bacteria-targeted and protease-activated antibacterial liposome (ACCLPs) was successfully synthesized through encapsulation of clove essential oil (CEO) by film dispersion method, embedding of casein by freeze-thaw method, and conjugation of C. jejuni antibody on the liposome membrane by post-insertion method. The average particle size, the essential oil encapsulation rate, the casein mosaic rate, and the antibody coupling efficiency of ACCLPs were determined as185.87 nm,16.9%,70.1% and 87.5%, respectively. The modification with C. jejuni antibody could significantly improve the targeting of ACCLPs to C. jejuni. Controlled release experiments showed that the exocrine protease from C. jejuni could hydrolyze the embedded casein and perforation on the ACCLPs, thus leading to a bacteria-dependent CEO release and significant prolonging the antibacterial effects of ACCLPs. Application results of ACCLPs on C. jejuni-contaminated foods showed that ACCLPs could effectively inhibit C. jejuni in a variety of meat products, fruits and vegetables and extend their shelf life without significantly affecting food quality. The results above in this work would provide a new view for the development of high efficient liposome-based antibacterial system of plant essential oil.

Bridging biotechnology and nanomedicine to produce biogreen whey-nanovesicles for intestinal health promotion

New intestinal health-promoting biotechnological nanovesicles were manufactured by combining the main environmental pollutant generated from the cheese-making process, whey, with phospholipid, sodium hyaluronate and dextrin, thus overcoming environmental and medical challenges. An efficient, consolidated and eco-friendly preparation method was employed to manufacture the vesicles and the bioactive whey was obtained by mesophilic dark fermentation without external inoculum through a homolactic pathway, which was operated in such a way as to maximize the production of lactic acid. The biotechnological nutriosomes and hyalonutriosomes were relatively small (∼100 nm) and characterized by the net negative surface charge (>-30 mV). The addition of maltodextrin to the liposomes and especially to the hyalurosomes significantly stabilized the vesicles under acidic conditions, simulating the gastric environment, as their size and polydispersity index were significantly lower (p < 0.05) than those of the other formulations. The vesicles were effectively internalized by Caco-2 cells and protected them against oxidative stress. Nutriosomes promoted the proliferation of Streptococcus salivarius, a human commensal bacterium, to a better extent (p < 0.05) than liposomes and hyalurosomes, as a function of the concentration tested. These findings could open a new horizon in intestinal protection and health promotion by integrating biotechnology, nanomedicine, sustainability principles and bio-circular economy.

Assessment of host-guest molecular encapsulation of eugenol using β-cyclodextrin

Eugenol is a natural compound with well-known repellent activity. However, its pharmaceutical and cosmetic applications are limited, since this compound is highly volatile and thermolabile. Nanoencapsulation provides protection, stability, conservation, and controlled release for several compounds. Here, eugenol was included in β-cyclodextrin, and the complex was characterized through X-ray diffraction analysis (XRD) and Fourier-transform infrared spectroscopy (FTIR). Additionally, we used molecular dynamics simulations to explore the eugenol-β-cyclodextrin complex stability with temperature increases. Our computational result demonstrates details of the molecular interactions and conformational changes of the eugenol-β-cyclodextrin complex and explains its stability between temperatures 27°C and 48°C, allowing its use in formulations that are subjected to varied temperatures.

Microencapsulation for Food Applications: A Review

Food products contain various active ingredients, such as flavors, nutrients, unsaturated fatty acids, color, probiotics, etc., that require protection during food processing and storage to preserve their quality and shelf life. This review provides an overview of standard microencapsulation technologies, processes, materials, industrial examples, reasons for market success, a summary of recent applications, and the challenges in the food industry, categorized by active food ingredients: flavors, polyunsaturated fatty acids, probiotics, antioxidants, colors, vitamins, and others. We also provide a comprehensive analysis of the advantages and disadvantages of the most common microencapsulation technologies in the food industry such as spray drying, coacervation, extrusion, and spray cooling. This review ends with future perspectives on microencapsulation for food applications.

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.

Eugenol-acacia gum-based bifunctional nanofibers as a potent antifungal transdermal substitute

Aim: Fungal biofilms interfere with the wound healing processes. Henceforth, the study aims to fabricate a biomaterial-based nano-scaffold with the dual functionalities of wound healing and antibiofilm activity. Methods: Nanofibers comprising acacia gum, polyvinyl alcohol and inclusion complex of eugenol in β-cyclodextrin (EG-NF) were synthesized using electrospinning. Antibiofilm studies were performed on Candida species, and the wound-healing activity was evaluated through an in vivo excision wound rat model. Results: The EG-NF potentially eradicated the mature biofilm of Candida species and their clinical isolates. Further, EG-NF also enhanced the re-epithelization and speed of wound healing in in vivo rat experiments. Conclusion: The study established the bifunctional applications of eugenol nanofibers as a transdermal substitute with antifungal potency.

Assessing the efficiency of essential oil and active compounds/poly (lactic acid) microcapsules against common foodborne pathogens

Essential oils' active compounds present great potential as a bactericidal agent in active packaging. The encapsulation in polymeric walls promotes their protection against external agents besides allowing controlled release. This work produced PLA capsules with three different active compounds, Cinnamomum cassia essential oil (CEO), eugenol (EEO), and linalool (LEO), by emulsion solvent evaporation method. Characterizations included SEM, Zeta potential, FTIR, TGA, and bactericidal activity against E. coli, S. aureus, L. monocytogenes, and Salmonella. The active compounds showed microbiological activity against all pathogens. CEO capsules showed superior colloidal stability. The active compounds' presence in all capsules was confirmed by FTIR analysis, with possible physical interaction between CEO, EEO, and the polymeric matrix, while LEO had a possible chemical interaction with PLA. TGA analysis showed a plasticizing effect of active compounds, and the loading efficiency was 39.7%, 50.7%, and 22.3% for CEO-PLA, EEO-PLA, and LEO-PLA, respectively. The capsules presented two release stages, sustaining activity against pathogens for up to 28 days, indicating a satisfactory internal morphology. This study presented methodology for encapsulation of antimicrobial compounds that can be suitable for active food packaging. CEO-PLA capsules regarding stability and antibacterial activity achieved the best results.

Influence of sodium caseinate, maltodextrin, pectin and their Maillard conjugate on the stability, in vitro release, anti-oxidant property and cell viability of eugenol-olive oil nanoemulsions

The influence of protein (sodium caseinate-SC), polysaccharide (maltodextrin-MD; pectin-PC) and their Maillard conjugates (sodium caseinate maltodextrin conjugate-SCMDC; sodium caseinate pectin conjugate-SCPCC) were studied on the physico-chemical and biological properties of eugenol nanoemulsions/powder. The chemical composition was optimized using Taguchi design. The particles size of eugenol nanoemulsions with SC, MD, PC, SCMDC and SCPCC were 104.6, 323.5, 1872, 181.7, and 454.4 nm, respectively while their zeta potentials were -31.2, -28.5, -21.4, -40.1 and -25.1 mV, respectively. Turbidity studies revealed higher stability of nanoemulsion prepared with Maillard conjugate (SCMDC) compared to protein or polysaccharides alone. The dispersion of SCMDC eugenol nanoparticles in buffer was prepared to study its stability at different pH (3.0, 5.0, and 7.0) and temperature (4°, 37°, 60 °C) range. In-vitro enzymatic release study showed 31 and 74% release of eugenol after 6 h at pH 2.4 and 7.4, respectively. In vitro antioxidant capacity of SCMDC encapsulated eugenol was higher than native eugenol, as demonstrated by free radical scavenging assays. In comparison to native eugenol, E:SCMDC eugenol showed reduced toxicity. These findings suggested that nanoencapsulated eugenol (E:SCMDC) have a huge potential in nutraceutical and therapeutic applications.

Characterization and antimicrobial activity of microencapsulated citral with dextrin by spray drying

Aim of this work was to evaluate the antimicrobial activity and physical characteristics of citral microencapsulated with dextrin (Dx) by spray drying. The encapsulation was optimized using response surface methodology (RSM), maximizing yield and efficiency, considering as independent variables the citral:Dx ratio (1:5 and 1:20) and the inlet air temperature (120 and 200 °C). Yield and efficiency under optimal conditions were 71.9% and 99.9%, respectively. Antimicrobial activity against Escherichia coli, Salmonella enterica, Staphylococcus aureus and Bacillus cereus of the citral microparticles obtained under optimal conditions and of free citral was evaluated using the disk diffusion methodology. Both compounds showed a broad spectrum inhibitory effect, being Escherichia coli and Bacillus cereus the most sensitive microorganisms. The inhibition ratio varied between 55 and 75%, and the antibacterial activity was maintained after microencapsulation. The minimum inhibitory concentrations of free citral were above 0.8 mg/mL. The optimal citral microparticles showed acceptable physicochemical characteristics and broad-spectrum antimicrobial activity. Polymer and emulsifier used in microencapsulation protected the functional activity of citral, thus suggesting that these microparticles could be used in the design of antimicrobial food systems to extend the shelf life of perishable foods.

Optimized preparation of eugenol microcapsules and its effect on hepatic steatosis in HepG2 cells

This study was aimed at evaluating the potential of peach gum (PG) and gelatin in the microencapsulation of eugenol and the intervention of eugenol microcapsules on hepatic steatosis in vitro. Response surface method (RSM) was used to optimize the encapsulation conditions of eugenol microcapsules. The microcapsules were characterized by scanning electron microscopy (SEM), dynamic Light Scattering (DLS), Fourier transform infrared spectroscopy (FT-IR) and release behavior in vitro was determined. The effect of eugenol microcapsules on free fatty acids (FFA) treated hepatocellular cells (HepG₂) cells was evaluated by oil red O staining and intracellular total cholesterol (TC) and triglyceride (TG) determination. The results showed that the optimal encapsulation conditions were as follows: the PG-gelatin ratio was 1.6:1.4, the core-wall ratio was 1.6:1.4, the pH was 4 and the emulsification speed was 9000 r/min. The optimized microcapsules were smooth spherical with a size of about 3.09 ± 0.58 μm and the encapsulation was confirmed by FT-IR. In vitro release behavior showed that eugenol microcapsules could be released stably in a neutral environment for 72 h. Oil red O staining showed that 50 and 100 μM eugenol microcapsules could significantly inhibit the lipid accumulation and reduce the TC and TG in steatotic HepG₂ cells induced by FFA. Therefore, PG and gelatin can be used as excellent carriers for the microencapsulation of volatile compounds in the field of biomedical industry, and eugenol microcapsules is a promising preparation for the treatment of nonalcoholic fatty liver disease (NAFLD).

Development of Electrospun Poly(3-hydroxybutyrate-co-3-hydroxyvalerate) Monolayers Containing Eugenol and Their Application in Multilayer Antimicrobial Food Packaging

In this research, different contents of eugenol in the 2.5-25 wt.% range were first incorporated into ultrathin fibers of poly(3-hydroxybutyrate-co-3-hydroxyvalerate) (PHBV) by electrospinning and then subjected to annealing to obtain antimicrobial monolayers. The most optimal concentration of eugenol in the PHBV monolayer was 15 wt.% since it showed high electrospinnability and thermal stability and also yielded the highest bacterial reduction against Staphylococcus aureus (S. aureus) and Escherichia coli (E. coli). This eugenol-containing monolayer was then selected to be applied as an interlayer between a structural layer made of a cast-extruded poly(3-hydroxybutyrate) (PHB) sheet and a commercial PHBV film as the food contact layer. The whole system was, thereafter, annealed at 160°C for 10 s to develop a novel multilayer active packaging material. The resultant multilayer showed high hydrophobicity, strong adhesion and mechanical resistance, and improved barrier properties against water vapor and limonene vapors. The antimicrobial activity of the multilayer structure was also evaluated in both open and closed systems for up to 15 days, showing significant reductions (R ≥ 1 and < 3) for the two strains of food-borne bacteria. Higher inhibition values were particularly attained against S. aureus due to the higher activity of eugenol against the cell membrane of Gram positive (G+) bacteria. The multilayer also provided the highest antimicrobial activity for the closed system, which better resembles the actual packaging and it was related to the headspace accumulation of the volatile compounds. Hence, the here-developed multilayer fully based on polyhydroxyalkanoates (PHAs) shows a great deal of potential for antimicrobial packaging applications using biodegradable materials to increase both quality and safety of food products.

Zein Nanoparticles Impregnated with Eugenol and Garlic Essential Oils for Treating Fish Pathogens

The supply of food derived from aquaculture has increased significantly in recent years. The aim of this industrial sector is to produce sustainable products to meet the needs of consumers, providing food security and nutritional benefits. The development of aquaculture has faced challenges including disease outbreaks that can cause substantial economic losses. These diseases can be controlled using chemicals such as antibiotics. However, the indiscriminate use of these substances can have major negative impacts on human health and the environment with the additional risk of the emergence of resistant organisms. The present manuscript describes the use of phytotherapy in association with nanotechnology in order to obtain a more effective and less harmful system for the control of bacterial diseases in fish. Zein nanoparticles associated with eugenol and garlic essential oil were prepared through antisolvent precipitation and characterized. Zein nanoparticles are promising carrier systems as zein proteins are biodegradable and biocompatible and, in this way, good candidates for encapsulation of active ingredients. The system presented good physicochemical properties with an average particle diameter of approximately 150 nm, a polydispersity index lower than 0.2, and a zeta potential of approximately 30 mV. High encapsulation efficiency was obtained for the active compounds with values higher than 90%, and the compounds were protected against degradation during storage (90 days). The nanoparticle formulations containing the botanical compounds also showed less toxicity in the tests performed with a biomarker (Artemia salina). In addition, the systems showed bactericidal activity against the important fish pathogenic bacteria Aeromonas hydrophila, Edwardsiella tarda, and Streptococcus iniae in vitro. The present study opens new perspectives for the use of botanical compounds in combination with nanotechnology to treat fish diseases caused by bacteria, contributing to a more sustainable fish chain production.

The Effect of Eugenol and Chitosan Concentration on the Encapsulation of Eugenol Using Whey Protein–Maltodextrin Conjugates

Eugenol has many functional properties for food and pharmaceutical purposes, especially as an antimicrobial agent. However, its use is constrained by its volatility and shelf life because it is easily degraded due to temperature, oxidation, and light. Research on encapsulation technology using biopolymers is still required to obtain the appropriate formulation in a eugenol delivery system. The aims of this research were to develop a new formulation of protein and polysaccharides in eugenol encapsulation and to determine the effect of eugenol and chitosan concentration on the characteristics of the emulsions and spray-dried powder produced. In this study, eugenol was encapsulated in whey protein–maltodextrin conjugates and chitosan through the double layer encapsulation method. The emulsions which were prepared with 2.0% eugenol were relatively more stable than those of 1.0% eugenol based on the polydispersity index and zeta potential values. Spray-dried powder which was prepared using an emulsion of 2.0% w/w eugenol and 0.33% w/w chitosan had the highest eugenol loading. The presence of chitosan resulted in more stable emulsions based on their zeta potential values, improved thermal stability of eugenol, increased eugenol loading to become twice as much as the loading obtained without chitosan, and modified release profile of eugenol from the spray-dried powders.

Characterization and application of the microencapsulated carvacrol/sodium alginate films as food packaging materials

The carvacrol (CAR) was microencapsulated by β-cyclodextrin (βCD). To extend the shelf-life of white mushrooms against Trichoderma sp., the microencapsulated CAR (βCD-CARM)/sodium alginate (SA) films were prepared and characterized. The antifungal, physical, and mechanical properties of the films were investigated in this study. The results showed that the βCD-CARM with a core-to-wall ratio of 1:10 had better encapsulation efficiency and antifungal activity against Trichoderma sp., which was isolated from postharvest white mushrooms stored at 4 °C. The optimum concentration of βCD-CARM against Trichoderma sp. in vitro was 15 g/L. The water resistance, mechanical properties, light barrier property and heat aging of the film were enhanced after adding βCD-CARM. The films with 30 g/L βCD-CARM could efficiently against Trichoderma sp. The performance of βCD-CARM/SA films was confirmed to control the release of CAR for enhanced antifungal activity. Besides, the βCD-CARM/SA films increased the activities of active free-radical scavenging enzymes to alleviate oxidative damage and delay senescence of the postharvest white mushrooms.

Self-Micro-Emulsifying Controlled Release of Eugenol Pellets: Preparation, In vitro/In vivo Investigation in Beagle Dogs

This report aimed to formulate self-micro-emulsifying (SMEDDS) controlled-release pellets delivery system to improve aqueous solubility and in vivo availability of eugenol, a main constituent of clove oil with multiple pharmacological activities. The optimal formulation of eugenol-SMEDDS was eugenol: ethyl oleate: cremophor EL: 1, 2-propylene glycol at the ratio of 5:5:12:8. The SMEDDS were observed under transmission electron microscopy (TEM), and the size distribution was measured with dynamic laser light scatting (DLS). The particle size, index of dispersity (PDI), and zeta potential (Z-potential) were 68.8 ± 0.1 nm, 0.285 ± 0.031, and - 11.62 ± 0.63 mV, respectively. Eugenol-SMEDDS exhibited substantial increased in vitro dissolution compared with the free eugenol. The eugenol-SMEDDS sustained-release pellets (eugenol-SMEDDS-SR pellets) comprising of eugenol-SMEDDS, hydroxypropyl methylcellulose (HPMC), microcrystalline cellulose (MCC), and ethyl cellulose (EC) coats were obtained via extrusion spheronization technique. Consequently, the obtained pellets observed under scanning electron microscopy (SEM) showed spherical shape with smooth surface, desirable drug loading capacity (7.18 ± 0.17%), greater stability, and controlled release. Meanwhile, the oral test showed that bioavailability of eugenol in pellets was highly improved 23.6-fold to the free eugenol. Overall, these results suggested that the improvement of the oral bioavailability of eugenol-SMEDDS-SR could be due to the successful incorporation of the drug into SMEDDS.

Nanoencapsulated essential oils embedded in ice improve the quality and shelf life of fresh whole seabream stored on ice

Ice containing essential oils (EOs) nanoencapsulated in β-cyclodextrins (β-CD) (named as EOs+β-CD ice) was used for stunning/slaughtering by hypothermia in ice slurry, and for ice storage of gilthead seabream. Clove essential oil (CEO) was used at fish stunning/slaughtering, while ice storage of whole fish was performed using a combination of carvacrol, bergamot and grapefruit EOs (CBG). Inclusion complexes CBG+β-CD were characterized, and antimicrobial effect was also evaluated. The kneading method used to form inclusion complexes with CBG showed a good complexation efficiency. Microbial, physical-chemical and sensory analyses were carried out to assess the quality changes of fresh whole seabream during ice storage at 2 °C for 17 days. Results (microbial, chemical and sensorial) indicated that seabream stunning/slaughtering and storage using EOs+β-CD ice (in low doses of 15 mg/kg ice for stunning, and 50 mg/kg ice for ice storage) improved the quality of fresh fish and extended the shelf-life up to 4 days.

Inclusion Complexes of Citronella Oil with β-Cyclodextrin for Controlled Release in Biofunctional Textiles

Biofunctional textiles with integrated drug-delivery systems can help in the fight against vector-borne diseases. The use of repellent agents derived from plants and oils is an alternative to DEET (N,N-diethyl-m-methylbenzamide), which has disadvantages that include toxic reactions and skin damage. However, some researchers report that oils can be ineffective due to reasons related to uncontrolled release. In this work, the mechanism of control of citronella oil (OC) complexed with β-cyclodextrin (βCD) on cotton (COT) and polyester (PES) textiles was investigated. The results obtained reveal that finishing cotton and polyester with β-cyclodextrin complexes allows for control of the release mechanism of the drug from the fabric. To assess the complexes formed, optical microscopy, SEM, and FTIR were carried out; the yield of complex formation was obtained by spectroscopy in the ultraviolet region; and controlled release was performed in vitro. Oil complexation with βCD had a yield of 63.79%, and it was observed that the release, which was in seconds, moved to hours when applied to fabrics. The results show that complexes seem to be a promising basis when it comes to immobilizing oils and controlling their release when modified with chemical crosslinking agents.

Chemical composition and radical scavenging activity of Amygdalus pedunculata Pall leaves' essential oil

The main objective of the current study was to investigate the components and radical scavenging activity of essential oil from Amygdalus pedunculata Pall leaves (APEO) extracted by an ultrasound-assisted method. Thirty-eight chemical components were identified in APEO using gas chromatography-mass spectrometry (GC-MS). APEO primarily consisted of alcohols (36.82%), esters (28.81%), ketones (1.47%), alkanes (18.61%) and phenols (8.93%). The most abundant compound was n-hexanol (33.49%). The antioxidant activity of APEO was characterized for 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical, hydroxyl radical (OH·), hydrogen peroxide (H₂O₂), and superoxide anion radical (O₂·^-) scavenging and Fe³⁺ reduction, and the IC₅₀ values were 2.32, 2.65, 2.42, 5.24 and 4.19 mg/mL, respectively. The IC₅₀ values for H₂O₂ scavenging and Fe³⁺ reduction of APEO were less than those of ascorbic acid (Vc; 3.15 and 5.13 mg/mL). The results showed that APEO has a high radical scavenging activity.

Chitosan microencapsulation of the dispersed phase of an O/W nanoemulsion to hydrochlorothiazide delivery

In view of biopharmaceutical limitations of hydrochlorothiazide (HCTZ), Trojan-type mucoadhesive systems were proposed, aiming to improve HCTZ pharmacological properties by modulating its release. Nanoemulsions were formed spontaneously by combining medium-chain triglycerides (Lipoid^® S75 and Pluronic^® F68) and high encapsulation efficiency was obtained. The mucoadhesive properties were provided by chitosan and microencapsulation of nanoemulsions in spray-dryer was successfully achieved by using Aerosil^® as wall material. The rapid redispersion of nanoemulsion in simulated fluids led to a fast and complete release of HCTZ in gastric medium. The pharmacodynamics of HCTZ was improved, extending the diuretic activity. Once a simple and low-energy method contributed to obtain stable mucoadhesive nanoemulsions, advantages in terms of production could also be achieved, allowing easy scaling up. This novel mucoadhesive Trojan particulate system of HCTZ showed to be a promising approach to overcome limitations in terms of absorption and consequently improve the therapeutic efficacy.