Insights from Syzygium aromaticum Essential Oil: Encapsulation, Characterization, and Antioxidant Activity.

Alginate encapsulates loaded with clove essential oil (CEO) were prepared by ionic gelation, with subsequent freeze-drying. The objective of the present work was to develop a product with the ability to protect CEO against its easy volatility and oxidation. The following techniques were used to characterize the formulations: eugenol release, degree of swelling, GC/MS, TGA/DSC, and SEM. The alginate solution (1.0%) containing different concentrations of CEO (LF1: 1.0%; LF2: 0.5%; LF3: 0.1%) was dropped into a 3.0% CaCl2 solution. After lyophilization, the encapsulated samples were wrinkled and rigid, with high encapsulation power (LF3: 76.9% ± 0.5). Three chemical components were identified: eugenol (the major one), caryophyllene, and humulene. The antioxidant power (LF1: DPPH IC50 18.1 µg mL-1) was consistent with the phenol content (LF1: 172.2 mg GAE g-1). The encapsulated ones were thermally stable, as shown by analysis of FTIR peaks, eugenol molecular structure was kept unaltered. The degree of swelling was 19.2% (PBS). The release of eugenol (92.5%) in the PBS solution was faster than in the acidic medium. It was concluded that the low-cost technology used allows the maintenance of the content and characteristics of CEO in the three concentrations tested, offering a basis for further research with essential oil encapsulates.

Chitosan-Polyvinyl Alcohol Nanocomposites for Regenerative Therapy.

Tissue accidents provide numerous pathways for pathogens to invade and flourish, causing additional harm to the host tissue while impeding its natural healing and regeneration. Essential oils (EOs) exhibit rapid and effective antimicrobial properties without promoting bacterial resistance. Clove oils (CEO) demonstrate robust antimicrobial activity against different pathogens. Chitosan (CS) is a natural, partially deacetylated polyamine widely recognized for its vast antimicrobial capacity. In this study, we present the synthesis of four membrane formulations utilizing CS, polyvinyl alcohol (PVA), and glycerol (Gly) incorporated with CEO and nanobioglass (n-BGs) for applications in subdermal tissue regeneration. Our analysis of the membranes' thermal stability and chemical composition provided strong evidence for successfully blending polymers with the entrapment of the essential oil. The incorporation of the CEO in the composite was evidenced by the increase in the intensity of the band of C-O-C in the FTIR; furthermore, the increase in diffraction peaks, as well as the broadening, provide evidence that the introduction of CEO perturbed the crystal structure. The morphological examination conducted using scanning electron microscopy (SEM) revealed that the incorporation of CEO resulted in smooth surfaces, in contrast to the porous morphologies observed with the n-BGs. A histological examination of the implanted membranes demonstrated their biocompatibility and biodegradability, particularly after a 60-day implantation period. The degradation process of more extensive membranes involved connective tissue composed of type III collagen fibers, blood vessels, and inflammatory cells, which supported the reabsorption of the composite membranes, evidencing the material's biocompatibility.

Clove Essential Oil (Syzygium aromaticum L. Myrtaceae): Extraction, Chemical Composition, Food Applications, and Essential Bioactivity for Human Health.

Clove (Syzygium aromaticum L. Myrtaceae) is an aromatic plant widely cultivated in tropical and subtropical countries, rich in volatile compounds and antioxidants such as eugenol, ß-caryophyllene, and α-humulene. Clove essential oil has received considerable interest due to its wide application in the perfume, cosmetic, health, medical, flavoring, and food industries. Clove essential oil has biological activity relevant to human health, including antimicrobial, antioxidant, and insecticidal activity. The impacts of the extraction method (hydrodistillation, steam distillation, ultrasound-assisted extraction, microwave-assisted extraction, cold pressing, and supercritical fluid extraction) on the concentration of the main volatile compounds in clove essential oil and organic clove extracts are shown. Eugenol is the major compound, accounting for at least 50%. The remaining 10-40% consists of eugenyl acetate, ß-caryophyllene, and α-humulene. The main biological activities reported are summarized. Furthermore, the main applications in clove essential oil in the food industry are presented. This review presents new biological applications beneficial for human health, such as anti-inflammatory, analgesic, anesthetic, antinociceptive, and anticancer activity. This review aims to describe the effects of different methods of extracting clove essential oil on its chemical composition and food applications and the biological activities of interest to human health.

Spraying Hatching Eggs with Clove Essential Oil Does Not Compromise the Quality of Embryos and One-Day-Old Chicks or Broiler Performance.

The objective of this study was to evaluate whether sanitizing hatching eggs with clove essential oil in the preincubation phase affects broiler performance and influences the hatch window and quality of embryos and one-day-old chicks. Hatching eggs (n = 1280; mean weight = 58.64 ± 0.49 g) from a batch of 37-week-old broiler breeder hens of the CPK (Pesadão Vermelho) lineage were randomly distributed into four treatments in the preincubation phase. The treatments consisted of three different sanitization procedures (spraying with grain alcohol, spraying with clove essential oil, and fumigation with paraformaldehyde) and a control treatment (nonsanitized). The lengths of the embryos and one-day-old chicks (one of the parameters used to assess bird quality) were not significantly different among the treatments, with means of 15.30 ± 1.41 and 18.37 ± 0.76 mm, respectively. Body weight, body weight gain, feed consumption, and feed conversion rate in different rearing periods did not differ significantly among the treatments. However, there was a significant difference in the percentage of survivability during the initial period (1 to 28 days) among the treatments. In conclusion, clove essential oil treatment did not negatively affect the quality of embryos and one-day-old chicks or the performance of broilers.

Lipidic Matrixes Containing Clove Essential Oil: Biological Activity, Microstructural and Textural Studies.

Clove essential oil (CEO) is known for having excellent antioxidant and antimicrobial properties, but the poor stability of its components to light and temperature compromise this activity. The aim of this study is to evaluate the textural, antioxidant, antimicrobial and microstructural properties of matrixes produced with representative natural waxes and CEO. Thus, waxy emulsifiers, such as beeswax, candelilla wax, carnauba wax, and ozokerite wax, were employed to create such matrixes. The thermal, microstructural, textural, wetting, antioxidant, antimicrobial and infrared characteristics of the matrixes were then studied. The diverse chemical composition (long-chain wax esters in carnauba wax and short-chain fatty acids and hydrocarbons in beeswax and ozokerite wax, respectively) explained the differences in wetting, texture, melting, and crystallization characteristics. Crystal forms of these matrix systems varied from grainy, oval, to needle-like shape, but keeping an orthorhombic allomorph. The alignment and reorganization of beeswax and ozokerite wax into needle-like crystals increased the matrix strength and adhesion force compared to those of carnauba and candelilla matrixes, which showed weak strength and grainy morphology. The former two waxes and their matrixes also showed the largest plasticity. These lipidic matrixes show potential use for topical applications having acceptable antioxidant and textural properties.

Clove essential oil in the sanitation of fertile eggs.

The aim of this study was to evaluate the efficacy of sanitizing fertile eggs with clove essential oil as an alternative to paraformaldehyde; effects on the reduction in eggshell microbial count, incubation yield, and neonatal chick quality were measured. A total of 1,460 brown fertile eggs with a mean weight of 58.64 ± 0.49 g (from 37-wk-old CPK [Pesadão Vermelho] breeder hens) were collected under aseptic conditions and randomly distributed into 4 treatments (nonsanitized and sanitized with grain alcohol, clove essential oil, and paraformaldehyde) before incubation. The count of total aerobic mesophilic bacteria was significantly lower after spraying with clove essential oil (2.30 ± 0.24 log10 CFU/mL) than on nonsanitized eggs (3.49 ± 0.34 log10 CFU/mL) or on eggs sprayed with grain alcohol (3.09 ± 0.14 log10 CFU/mL) but did not differ significantly from the count in the paraformaldehyde group (2.23 ± 0.29 log10 CFU/mL). The hatchability of fertile eggs differed significantly between the studied treatments. The mean values for the eggs treated with clove essential oil (84.69 ± 1.65%) and paraformaldehyde (81.87 ± 3.92%) were statistically similar but were higher than the negative control (74.03 ± 3.58%) and grain alcohol (73.59 ± 2.87%) values. In the Pasgar© score assessment, it was determined that the clove essential oil (9.21 ± 0.89%) had a superior effect on the physical quality of the chicks compared with the effects of the other treatments. Clove essential oil is effective and safe for eggs intended for incubation. Its use as an alternative to paraformaldehyde in the sanitation of fertile eggs is strongly recommended.

Alternative sanitizers to paraformaldehyde for incubation of fertile eggs.

The aim of this study was to evaluate an ethanolic extract of propolis and clove essential oil as a substitute for paraformaldehyde for the sanitation of fertile eggs. In total, 1,800 hatching eggs (from 40-week-old CPK [Pesadão Vermelho] breeder hens) were randomly distributed among the treatments (grain alcohol, clove essential oil, ethanolic extract of propolis, and paraformaldehyde). Spraying was the application method for all treatments except for paraformaldehyde, for which fumigation was used. The experimental design was a randomized block design with 4 treatments. Analysis of the incubation parameters was based on 6 replications per treatment. The egg weight loss was lower in the eggs treated with ethanolic extract of propolis (8.59 ± 3.34%) than in the eggs treated with grain alcohol (13.40 ± 2.87%), clove essential oil (12.96 ± 3.33%), and paraformaldehyde (13.05 ± 3.24%). The hatchability of the fertile eggs (51.39 ± 5.81%) and the hatchability of the set eggs (44.74 ± 6.79%) were negatively affected by the application of ethanolic extract of propolis. Late mortality of eggs treated was higher than early mortality in the grain alcohol (12.14 ± 4.72%; 2.86 ± 3.30%), clove essential oil (4.60 ± 5.95%; 3.03 ± 3.50%), and ethanolic extract of propolis (36.63 ± 6.60%, 11.98 ± 4.30%) treatments. The eggs treated with clove essential oil (67.90 ± 1.87%), paraformaldehyde (67.80 ± 1.85%), or grain alcohol (67.50 ± 1.92%) presented chick yields as expected. However, despite the ideal yield of eggs treated with ethanolic extract of propolis (69.25 ± 1.68%), its application at the concentration used in the present research is not recommended. Clove essential oil, when sprayed on fertile eggs as a sanitizing agent, did not differ from paraformaldehyde in relation to hatchery performance parameters.

Preparation of polymer nanoparticles loaded with Syzygium aromaticum essential oil: an oral potential application / Preparación de nanoparticulas polimericas cargadas con aceite esencial de Syzygium aromaticum: una potencial aplicación oral

Due to the biological activities of Syzygium aromaticum essential oil, its incorporation in methacrylate polymeric (Eudragit E100) nanoparticles (NP), physical characterization, and antimicrobial essays were evaluated. The clove bears great potential for applications in dentistry. The oil was obtained by hydrodistillation and oil loaded NP using the nanoprecipitation method. Particle size and polydispersity index were determined by photon correlation spectroscopy, and physical morphology by electron microscopy. Loading capacity and in vitro eugenol release were evaluated by gas mass chromatography, and the antimicrobial activity of oil loaded-NP was calculated against Streptococcus mutans. Different chemical ingredients were characterized, and eugenol was the principal compound with 51.55%. Polymer content was directly related to NP homogenous size, which was around 150 nm with spherical morphology. A 73.2% loading capacity of eugenol was obtained. Oil loaded NP presented a fickian-type release mechanism of eugenol. Antimicrobial activity to 300 µg/mL was obtained after 24 h.

Debido a las actividades biológicas del aceite esencial de Syzygium aromaticum, se evaluó su incorporación en nanopartículas (NP) de metacrilato polimérico (Eudragit E100), su caracterización y ensayos antimicrobianos. El clavo tiene un gran potencial para aplicaciones en odontología. El aceite se obtuvo por hidrodestilación y las NP cargado de aceite utilizando el método de nanoprecipitación. El tamaño de partícula y el índice de polidispersidad se determinaron mediante espectroscopia de correlación fotónica y su morfología por microscopía electrónica. La capacidad de carga y la liberación de eugenol in vitro se evaluaron mediante cromatografía de gases en masa, y la actividad antimicrobiana se evaluó contra Streptococcus mutans. Se caracterizaron diferentes ingredientes químicos, siendo el eugenol el principal compuesto con 51.55%. El contenido de polímero se relacionó directamente con el tamaño homogéneo de NP, que fue de alrededor de 150 nm con morfología esférica. Se obtuvo un 73,2% de capacidad de carga de eugenol. El aceite cargado en NP presentó un mecanismo de liberación de eugenol de tipo fickiano. La actividad antimicrobiana a 300 µg/mL se obtuvo después de 24 h.

Storage stability of minimally processed pinhão by using edible coatings with antimicrobial characteristics / Conservação de pinhão minimamente processado pelo uso de revestimentos comestíveis com características antimicrobianas

The pinhão shows high nutritional value; however, its consumption is still low owing to the long cooking time required because it is hard to peel, and it is susceptible to sprouting, larval infestation, and fungal contamination. Thus, this study aimed to evaluate the storage stability of minimally processed pinhão by using edible coatings with antimicrobial characteristics. The pinhões were subjected to minimal processing with the following treatments: Treatment A - control; Treatment B - chitosan; Treatment C - xanthan gum and clove essential oil. After drying, they were packed in polyethylene terephthalate and stored at 4 °C for nine days. The pinhões were analyzed for mass loss, total acidity, reducing sugars, vitamin C, color, firmness, respiratory rate, sensory characteristics, and microbial growth. In general, no differences were observed in mass loss, reducing sugars, and oxygen concentrations of the pinhões after any treatment. In addition, we observed a reduction in acidity and carbon dioxide concentrations, maintenance of color parameters, and the absence of growth of thermotolerant coliforms and coagulase positive Staphylococcus. Although the minimal processing did not increase the respiratory rate of pinhões, it did not stop the process of seed maturation. Of the coatings evaluated, chitosan coating of the pinhões was associated with a higher content of vitamin C as well as a lower number of psychrotrophic microorganisms. The coatings did not influence the taste and aroma of the minimally processed pinhões.(AU)

O pinhão apresenta alto valor nutricional, entretanto seu consumo ainda é pouco expressivo devido ao longo tempo de cocção, por apresentar um difícil descasque, ser susceptível ao processo de brotamento, infestação por larvas e deterioração fúngica. Assim, o presente trabalho teve por objetivo avaliar a conservação de pinhões minimamente processados por meio de revestimentos comestíveis com características antimicrobianas. Os pinhões foram submetidos ao processamento mínimo e após aos diferentes tratamentos: Tratamento A - controle; Tratamento B - quitosana; Tratamento C - xantanae óleo essencial de cravo-da-índia. Após, foram secos sob ventilação forçada, acondicionados em embalagem de Polietileno Tereftalato (PET) e armazenados a 4 ºC, durante 9 dias. Foram realizadas avaliações de perda de massa, acidez total titulável, açúcares redutores, vitamina C, firmeza, cor, taxa respiratória, análise sensorial e microbiológica. De uma forma geral, independente do tratamento, pôde se observar comportamento semelhante nas características dos pinhões, em relação ao aumento da perda de massa, dos açúcares redutores, da concentração de oxigênio e da deterioração fisiológica. Além disso, foi observada a redução da acidez e da concentração de dióxido de carbono, bem como a manutenção dos parâmetros de cor e a ausência de crescimento de coliformes termotolerantes e Staphylococcus coagulase positiva. O processamento mínimo não elevou a taxa respiratória dos pinhões, porém não freou o processo de maturação das sementes. Dos revestimentos avaliados, a quitosana possibilitou a obtenção de pinhões com maior teor de vitamina C e contagem de microrganismos psicrotróficos. Os revestimentos não influenciaram no sabor e aroma dos pinhões minimamente processados.(AU)

Storage stability of minimally processed pinhão by using edible coatings with antimicrobial characteristics / Conservação de pinhão minimamente processado pelo uso de revestimentos comestíveis com características antimicrobianas

The pinhão shows high nutritional value; however, its consumption is still low owing to the long cooking time required because it is hard to peel, and it is susceptible to sprouting, larval infestation, and fungal contamination. Thus, this study aimed to evaluate the storage stability of minimally processed pinhão by using edible coatings with antimicrobial characteristics. The pinhões were subjected to minimal processing with the following treatments: Treatment A - control; Treatment B - chitosan; Treatment C - xanthan gum and clove essential oil. After drying, they were packed in polyethylene terephthalate and stored at 4 °C for nine days. The pinhões were analyzed for mass loss, total acidity, reducing sugars, vitamin C, color, firmness, respiratory rate, sensory characteristics, and microbial growth. In general, no differences were observed in mass loss, reducing sugars, and oxygen concentrations of the pinhões after any treatment. In addition, we observed a reduction in acidity and carbon dioxide concentrations, maintenance of color parameters, and the absence of growth of thermotolerant coliforms and coagulase positive Staphylococcus. Although the minimal processing did not increase the respiratory rate of pinhões, it did not stop the process of seed maturation. Of the coatings evaluated, chitosan coating of the pinhões was associated with a higher content of vitamin C as well as a lower number of psychrotrophic microorganisms. The coatings did not influence the taste and aroma of the minimally processed pinhões.

O pinhão apresenta alto valor nutricional, entretanto seu consumo ainda é pouco expressivo devido ao longo tempo de cocção, por apresentar um difícil descasque, ser susceptível ao processo de brotamento, infestação por larvas e deterioração fúngica. Assim, o presente trabalho teve por objetivo avaliar a conservação de pinhões minimamente processados por meio de revestimentos comestíveis com características antimicrobianas. Os pinhões foram submetidos ao processamento mínimo e após aos diferentes tratamentos: Tratamento A - controle; Tratamento B - quitosana; Tratamento C - xantanae óleo essencial de cravo-da-índia. Após, foram secos sob ventilação forçada, acondicionados em embalagem de Polietileno Tereftalato (PET) e armazenados a 4 ºC, durante 9 dias. Foram realizadas avaliações de perda de massa, acidez total titulável, açúcares redutores, vitamina C, firmeza, cor, taxa respiratória, análise sensorial e microbiológica. De uma forma geral, independente do tratamento, pôde se observar comportamento semelhante nas características dos pinhões, em relação ao aumento da perda de massa, dos açúcares redutores, da concentração de oxigênio e da deterioração fisiológica. Além disso, foi observada a redução da acidez e da concentração de dióxido de carbono, bem como a manutenção dos parâmetros de cor e a ausência de crescimento de coliformes termotolerantes e Staphylococcus coagulase positiva. O processamento mínimo não elevou a taxa respiratória dos pinhões, porém não freou o processo de maturação das sementes. Dos revestimentos avaliados, a quitosana possibilitou a obtenção de pinhões com maior teor de vitamina C e contagem de microrganismos psicrotróficos. Os revestimentos não influenciaram no sabor e aroma dos pinhões minimamente processados.

Active nanocomposite films based on soy proteins-montmorillonite- clove essential oil for the preservation of refrigerated bluefin tuna (Thunnus thynnus) fillets.

This manuscript evaluates the potential application of active nanocomposite films based on soy protein isolate (SPI)-montmorillonite (MMT)-clove essential oil (CEO) to the preservation of muscle fillets of bluefin tuna (Thunnus thynnus) during refrigerated storage, and furthermore analyzes whether the clay diffuses from the package to food. SPI films with: CEO (SPI-CEO), MMT (SPI-MMT), or both CEO and MMT (SPI-MMT-CEO), were prepared and used to cover tuna fillets during 17days of storage at 2°C. Polyethylene films were also used as control. Protein films nanoreinforced with 10g MMT/100g SPI and activated with CEO were able to decrease microbial growth (evaluated by TVBN and microorganism counts) and lipid autooxidation (evaluated according to the TBA index, FTIR and color parameters) of tuna fillets during the storage period studied. The presence of clay seemed to favor the release of the active principles of clove oil by prolonging its antimicrobial (especially effective to inhibit Pseudomonas spp.) and antioxidant activity over time without observing the diffusion of the clay's own metals (Si and Al) from the nanocomposite materials to the muscle of fish. These results are encouraging for the use of nanocomposite films in food packaging.

Microbicide activity of clove essential oil (Eugenia caryophyllata)

Clove essential oil, used as an antiseptic in oral infections, inhibits Gram-negative and Gram-positive bacteria as well as yeast. The influence of clove essential oil concentration, temperature and organic matter, in the antimicrobial activity of clove essential oil, was studied in this paper, through the determination of bacterial death kinetics. Escherichia coli, Staphylococcus aureus and Pseudomonas aeruginosa were the microorganisms selected for a biological test. To determine the temperature effect, they were assayed at 21° and 37° C. The concentration coefficient was determined with 0.4%, and 0.2% of essential oil. The influence of the presence of organic matter was determined with 0.4% of essential oil. The results obtained demonstrated that Escherichia coli were more sensitive even though the essential oil exerted a satisfactory action in three cases. In the three microbial species, 0.4% of essential oil at 21º C have reduced the bacterial population in 5 logarithmic orders. Organic matter reduces the antibacterial activity even though the bactericide efficacy was not lost. Clove essential oil can be considered as a potential antimicrobial agent for external use.(AU)

Microbicide activity of clove essential oil (Eugenia caryophyllata)

Clove essential oil, used as an antiseptic in oral infections, inhibits Gram-negative and Gram-positive bacteria as well as yeast. The influence of clove essential oil concentration, temperature and organic matter, in the antimicrobial activity of clove essential oil, was studied in this paper, through the determination of bacterial death kinetics. Escherichia coli, Staphylococcus aureus and Pseudomonas aeruginosa were the microorganisms selected for a biological test. To determine the temperature effect, they were assayed at 21° and 37° C. The concentration coefficient was determined with 0.4%, and 0.2% of essential oil. The influence of the presence of organic matter was determined with 0.4% of essential oil. The results obtained demonstrated that Escherichia coli were more sensitive even though the essential oil exerted a satisfactory action in three cases. In the three microbial species, 0.4% of essential oil at 21º C have reduced the bacterial population in 5 logarithmic orders. Organic matter reduces the antibacterial activity even though the bactericide efficacy was not lost. Clove essential oil can be considered as a potential antimicrobial agent for external use.

Microbicide activity of clove essential oil (Eugenia caryophyllata).

Clove essential oil, used as an antiseptic in oral infections, inhibits Gram-negative and Gram-positive bacteria as well as yeast. The influence of clove essential oil concentration, temperature and organic matter, in the antimicrobial activity of clove essential oil, was studied in this paper, through the determination of bacterial death kinetics. Escherichia coli, Staphylococcus aureus and Pseudomonas aeruginosa were the microorganisms selected for a biological test. To determine the temperature effect, they were assayed at 21° and 37° C. The concentration coefficient was determined with 0.4%, and 0.2% of essential oil. The influence of the presence of organic matter was determined with 0.4% of essential oil. The results obtained demonstrated that Escherichia coli were more sensitive even though the essential oil exerted a satisfactory action in three cases. In the three microbial species, 0.4% of essential oil at 21° C have reduced the bacterial population in 5 logarithmic orders. Organic matter reduces the antibacterial activity even though the bactericide efficacy was not lost. Clove essential oil can be considered as a potential antimicrobial agent for external use.

Scavenger Activity Evaluation of the Clove Bud Essential Oil (Eugenia caryophyllus) and Eugenol Derivatives Employing ABTS Decolorization.

The essential oil (EO) of clove bud dried fruits from Eugenia caryophyllus was obtained by a conventional hydrodistillation process in an excellent yield (11.7 %). Its chemical composition was analyzed by GC-MS, identifying eugenol as a main constituent (60.5%). Four eugenol-like molecules, γ-diisoeugenol, hydroxymethyleugenol, dihydroeugenol and 1,3-dioxanylphenol, were synthesized using eugenol or isoeugenol as initial precursors under green chemistry protocols. To evaluate the possible antioxidant capacity of eugenol compounds including the clove bud EO, the Trolox® Equivalent Antioxidant Capacity value, obtained by the ABTS(+•) radical-cation discoloration method, was employed. The methodology was performed in a UV-Vis reader of 96-well microplates (dilution methodology), using well-known antioxidant agents (BHA, BHT and vitamin E) as reference compounds. It was found that the prepared eugenol derivatives had a more potent free radical scavenger activity than the reference compounds. In particular, the most active molecules, γ-diisoeugenol and 1,3-dioxanylphenol, were ca. 3-fold more potent than vitamin E.