Effects of cinnamon, rosemary and oregano on growth performance, blood biochemistry, liver enzyme activities, excreta microbiota and ileal morphology of Campylobacter jejuni-challenged broiler chickens.

BACKGROUND: Phytogenic additives would be helpful to mitigate the detrimental impact of Campylobacter jejuni on broiler chickens. OBJECTIVE: The experiment aimed to assess the effects of cinnamon, rosemary and oregano powder on physiological responses of broiler chickens challenged with C. jejuni from 0 to 42 days of age. METHODS: A total of 192 one-day-old male broiler chickens were divided into 6 treatment groups. The treatments included: negative control (NC; basal diet without additives and no C. jejuni challenge), positive control (PC; basal diet with C. jejuni challenge), PC with cinnamon, rosemary or oregano powder (3 g/kg each), and PC with Erythromycin (55 mg/kg). Except for the NC group, all chicks were orally challenged with 2 × 108 CFU/mL C. jejuni daily from days 21-25. Feed intake, body weight gain (BWG), feed conversion ratio (FCR), energy efficiency ratio (EER) and protein efficiency ratio (PER) were assessed during the rearing period (0-42 days). On day 42 of age, fresh excreta samples were collected from each pen to determine apparent dry matter digestibility and excreta microbiota. In addition, at the end of the experiment, blood samples were collected to evaluate blood profile and liver enzyme activities. RESULTS: C. jejuni challenge (PC treatment) decreased BWG, EER and PER, while increasing FCR of broiler chickens (p < 0.05), whereas rosemary, oregano and Erythromycin improved these performance parameters akin to NC. PC diet showed negative effect in ileal morphology, alleviated by additives except cinnamon (p < 0.05). Dietary additives successfully reduced Campylobacter levels and increased Lactobacilli counts in the PC. Rosemary and oregano lowered plasma total cholesterol (p < 0.05). Alanine aminotransferase elevation by C. jejuni challenge in the PC group was prevented by rosemary, oregano and Erythromycin (p < 0.05). CONCLUSIONS: Oregano and rosemary alleviate the impact of C. jejuni challenge.

Evaluation of Chemical Profile and Biological Properties of Extracts of Different Origanum vulgare Cultivars Growing in Poland.

This research studied the phenolic content compared with the antioxidant properties of various O. vulgare (Lamiaceae) cultivars grown in Poland. The research results in this paper indicate that the dominant ingredient in all oregano cultivars was rosmarinic acid, known for its strong antioxidant properties. The highest amounts of rosmarinic acid (87.16 ± 4.03 mg/g dm) were identified in the O. vulgare spp. hirtum (Link) Ietsw. Other metabolites identified in the studied extracts include luteolin O-di-glucuronide-O-di-pentoside (30.79 ± 0.38 mg/g dm in the 'Aureum' cultivar), 4'-O-glucopyranosyl-3', 4'-dihydroxy benzyl-protocatechuate (19.84 ± 0.60 mg/g dm in the 'Margerita' cultivar), and p-coumaroyl-triacetyl-hexoside (25.44 ± 0.18 mg/g dm in the 'Margerita' cultivar). 'Hot & spicy' and 'Margerita' cultivars were characterized by the highest activity in eliminating OH• and O2•- radicals. Extracts from Greek oregano had the highest ability to scavenge DPPH radicals and chelate iron ions. This research has also provided new evidence that oregano has anti-migratory, cytotoxic properties and influences the viability of gastric cancer cells (the highest cytotoxicity was attributed to the 'Hot & spicy' cultivar, which performed the worst in antioxidant properties tests). Extracts from the tested cultivars at a concentration of 0.625% effectively inhibited the growth of S. aureus and P. aeruginosa bacteria. It seems that the oregano grown in Poland is of good quality and can be successfully grown on a large scale if the appropriate use is found.

Development of hybrid polyvinylpyrrolidone/carboxymethyl cellulose/collagen incorporated oregano scaffolds via direct ink write printing for potential wound healing applications.

Additive manufacturing can develop regenerative scaffolds for wound healing. 3D printing offers meticulous porosity, mechanical integrity, cell adhesion and cost-effectiveness. Herein, we prepared ink composed of carboxymethyl cellulose (CMC), polyvinylpyrrolidone (PVP), collagen, and oregano extract for the fabrication of tissue constructs. The blend was optimized to form a homogeneous ink and rheological characterization demonstrated shear thinning behavior. The scaffolds were printed using Direct Ink Write (DIW) at a flow speed of 4 mm3/s and a layer height of 0.18 mm. The fabricated scaffolds demonstrated an ultimate tensile strength (UTS) and toughness of 730 KPa and 2.72 MJ/m3, respectively. Scanning Electron Microscopy (SEM) revealed an average pore size of 300 ± 30 µm. Fourier transform infrared spectroscopy (FTIR) analysis confirmed that all materials were present. The contact angle of the composite scaffold was 68° ± 1°. Moreover, the scaffolds presented 82 % mass loss (degradation) in phosphate buffer saline (PBS) over 14 days. The composite scaffold exhibited inhibition zones of 9 mm and 12 mm against Staphylococcus aureus and Escherichia coli, respectively. The PVP/CMC/collagen/oregano 3D printed scaffolds exhibited excellent biocompatibility with the mesenchymal stem cells and humman dermal fibroblast cells, confirmed by water-soluble tetrazolium - 8 (WST-8) assay (test conducted for 7 days). The enhanced angiogenic potential of said scaffold was assesed by release of vascular endothelial growth factor followed by further validation through in-vivo CAM assay. Thus, confirming suitability for the potential wound healing application.

Characterization of sodium alginate film containing zein-Arabic gum nanoparticles encapsulated with oregano essential oil for chilled pork packaging.

Chilled pork retains most of its nutrients but is prone to deterioration during the production-to-consumption process. To address this issue this study aimed to develop zein-Arabic gum composite nanoparticles loaded with oregano essential oil (ZAG-OEO) and incorporate them into sodium alginate films to enhance the freshness and shelf life of chilled pork. Sodium alginate, known for its excellent film-forming properties, was selected as the matrix to prepare ZAG-OEO-containing sodium alginate films (SA-ZAG-OEO). The results revealed that the tensile strength and elongation at break of the prepared films were 47.73 ± 2.15 MPa and 6.27 ± 0.21 %, respectively, at a 2.5 % nanoparticle concentration. The water contact angle of the films incorporating nanoparticles reached 81.5 ± 1.95°. The incorporation of nanoparticles enhanced the thermal stability and antibacterial activity of the films. The prepared films were utilized for the storage of chilled pork, and the quality changes were analyzed. The results demonstrate that SA-ZAG-OEO films inhibit microbial growth and lipid oxidation, thereby delaying pork spoilage. This study offers new insights into extending the shelf life of chilled pork and developing advanced meat preservation methods for the future development of the meat industry.

Effects of essential oil of Origanum onites and its major component carvacrol on the expression of toxicity pathway genes in HepG2 cells.

BACKGROUND: Origanum species have been used in various commercial constructions as a remedy against burns and wounds, agriculture, alcoholic drinks, fragrance, and flavoring substances of food products. The essential oil of Origanum onites L. (EOOO) and its component carvacrol (CV) possesses a wide range of biological activities including anti-cancer activity. PURPOSE: The purpose of this study was to investigate the growth inhibitory activity of the essential oil and its major component CV and then hepatotoxicity pathway-related genes in HepG2 cells. METHODS: The effects of the EOOO and CV on cell growth and mRNA expressions of 84 hepatotoxicity pathway-related genes were investigated in HepG2, using trypan blue exclusion/ bromodeoxyuridine (BrdU) incorporation tests and real-time-polymerase chain reaction (RT-PCR) array, respectively. RESULTS: The EOOO and CV inhibited cell growth with IC50 values of 0.08 µg/mL and 45 µg/mL, respectively, after 24 h. Real-time, reverse-transcription-polymerase chain reaction (RT2-PCR) array analysis revealed that expressions of 32 genes out of 84 were changed at least 2-fold or more in the EOOO-treated cells. Among them, expression levels of 17 genes were elevated, while expression levels of 15 genes were diminished. Furthermore, after exposure of cells to 45 µg/mL of CV, the expression of 8 genes was increased while the other 8 genes were decreased. Both the EOOO and carvacrol affected the expression of 48 genes of HepG2 cells which are involved in the hepatotoxicity pathway, indicating their hepatoprotective and possible anti-hepatocarcinogenic effects. CONCLUSION: The present study demonstrates that the essential oil of Origanum onites and carvacrol can be used in various applications such as anticancer or herbal drugs, since its non-hepatotoxicity.

Effects of oregano and/or rosemary extracts on growth performance, digestive enzyme activities, cecal bacteria, tight junction proteins, and antioxidants-related genes in heat-stressed broiler chickens.

The study examined the impact of adding oregano extract and/or rosemary to broiler diets to counteract the growth inhibition caused by heat stress (HS). It also investigated the effects on the activity of digestive enzymes, microbiological composition, and the expression of antioxidant and tight junction-related proteins. Three hundred- and fifty-day-old male broilers, were randomly assigned to 7 treatment groups, with each group comprising 5 replicates, and each replicate containing 10 chicks in a cage. The diets were: 1) a basal diet, 2) a diet supplemented with 50 mg/kg of rosemary, 3) a diet supplemented with 100 mg/kg of rosemary, 4) a diet supplemented with 50 mg/kg of oregano, 5) a diet supplemented with 100 mg/kg of oregano, 6) a combination diet containing 50 mg/kg each of rosemary and oregano, and 7) a combination diet containing 100 mg/kg each of rosemary and oregano. Dietary oregano extract enhanced the growth and feed utilization of heat-stressed birds, especially at a concentration of 50 mg/kg. Moreover, oregano extract improved jejunal protease and amylase activities. The extracts of rosemary and oregano significantly reduced IgG and IgM levels. Dietary 50 mg oregano extract significantly upregulated intestinal integrity-related genes including jejunal CLDNI, ZO-1, ZO-2, and MUC2. Dietary 50 mg oregano extract significantly downregulated hepatic NADPH oxidase 4 (NOX4) and nitric oxide synthase 2 (NOS2) expressions. Our results suggest that incorporating oregano leaf extract into the diet at a concentration of 50 mg/kg improves the growth performance of broilers exposed to heat stress. This improvement could be attributed to enhanced gut health and the modulation of genes associated with oxidative stress and tight junction proteins.

Biodegradation study of poly(hydroxybutyrate-co-hydroxyvalerate)/halloysite/oregano essential oil compositions in simulated soil conditions.

The aim of this work was to evaluate the influence of halloysite clay nanoparticles - unmodified (Hal) and organically modified (mHal) - and oregano essential oil (OEO), used as an antimicrobial agent in active packaging, on the biodegradation behavior of poly(hydroxybutyrate-co-hydroxyvalerate) (PHBV) films. Five samples were prepared by melt mixing using 3 wt% clay, and 8 wt% and 10.4 wt% OEO. PHBV compositions containing OEO presented the highest rate of biodegradation, achieving 46% of mass loss after aging for 12 weeks in simulated soil. The addition of clay nanoparticles reduced the polymer's biodegradation to 32%. The compositions containing OEO showed a rough and layered surface with visible cracks, indicating degradation occurring through layer-by-layer erosion from the surface. This degradation was confirmed by the chemical changes on the surface of all samples, with a slight decrease in molar masses. The composition containing 8 wt% OEO presented an increase in the crystallization degree as a result of the preferential consumption of amorphous phase, whereas for the compositions containing clay nanoparticles, both crystalline and amorphous regions were degraded at similar rates. Therefore, the combination of additives allows the biodegradation process of PHBV to be controlled for use in the production of active packaging.

Food safety control in poultry industry: prevalence and antimicrobial susceptibility of Escherichia coli isolated from raw chicken and the potential use of Origanum essential oils as alternative to antibiotics.

1. The extensive use of antimicrobials in poultry production may contribute to the emergence of resistant bacteria. This study was conducted to determine the prevalence and resistance of different E. coli strains isolated from raw chicken meat and to investigate the possibility to use Lebanese native oregano essential oils as alternatives.2. In total, 250 chickens from Lebanese markets were examined for the presence of E. coli. Isolates were then screened for susceptibility using 19 antibiotics and two essential oils extracted from oregano plants.3. Of the 250 chickens tested, 80% were contaminated with E. coli. Main resistance was seen against amoxycillin, ampicillin, penicillin, tetracycline, tylosin, streptomycin and erythromycin. The highest rate of sensitivity was found in 86.1% of strains to Amoxycillin/Clavulanic acid, 80.09% to Tilmicosin. Both essential oils from Origanum syriacum (98%) and O. ehrenbergii (97.3%) showed promising potential in inhibiting the growth of the tested bacteria. Oil from O. syriacum exhibited superior efficacy against 200 E. coli strains, inhibiting 46.1% at 200 mg/l and all at 400 mg/l, while O. ehrenbergii oil showed slightly lower inhibition, affecting 41.6% at 200 mg/l and all at 400 mg/l.

Development and Evaluation of Microencapsulated Oregano Essential Oil as an Alternative Treatment for Candida albicans Infections.

Vulvovaginal candidiasis (VVC) is characterized as a very common fungal infection that significantly affects women's health worldwide. Essential oils (EOs) are currently being evaluated as an alternative therapy. The development of efficient techniques such as micro- or nanoencapsulation for protecting and controlling release is essential to overcome the limitations of EO applications. Therefore, the aim of this study was to develop and characterize oregano EO-loaded keratin microparticles (OEO-KMPs) as a potential treatment for VVC. OEO-KMPs were produced using high-intensity ultrasonic cycles and characterized in terms of morphological and physicochemical parameters. In vitro evaluation included assessing the toxicity of the OEO-KMPs and their effect against Candida albicans using microdilution and agar diffusion, while the activity against biofilm was quantified using colony forming units (CFU). The efficacy of the OEO-KMPs in an in vivo VVC mouse model was also studied. Female BALB/c mice were intravaginally infected with C. albicans, 24 h postinfection animals were treated intravaginally with 15 µL of OEO-KMPs and 24 h later vaginal fluid was analyzed for C. albicans and Lactobacillus growth (CFU mL-1). The results showed the stability of the OEO-KMPs over time, with high encapsulation efficiency and controlled release. This nanoparticle size facilitated penetration and completely inhibited the planktonic growth of C. albicans. In addition, an in vitro application of 2.5% of the OEO-KMPs eradicated mature C. albicans biofilms while preserving Lactobacillus species. In in vivo, a single intravaginal application of OEO-KMPs induced a reduction in C. albicans growth, while maintaining Lactobacillus species. In conclusion, this therapeutic approach with OEO-KMPs is promising as a potential alternative or complementary therapy for VVC while preserving vaginal microflora.

Evaluation of the activity and mechanisms of oregano essential oil against PRV in vivo and in vitro.

BACKGROUND: The Pseudorabies Virus (PRV) leading to pseudorabies and causes huge economic losses in pig industry. The development of novel PRV variations has diminished the efficacy of traditional vaccinations, and there is yet no medication that can stop the spread of PRV infection. Therefore, PRV eradication is challenging. Oregano essential oil, the plant-based ingredient for medication feed have been shown to has strong anti-herpesvirus activity, but no anti-PRV function has been reported. RESULTS: The current study assessed the anti-pseudorabies virus (PRV) activity of oregano essential oil and explored its mechanisms and most effective components against PRV. Our in vivo findings demonstrated that oregano essential oil could decrease the PRV load in tissues, mitigate tissue lesions, and enhance the survival rate of mice. The potential antiviral mechanism involves augmenting humoral and cellular immune responses in PRV-infected mice. To further investigate the most effective components of oregano essential oil against PRV, an in vitro study was conducted, revealing that oregano essential oil and its main constituents, carvacrol and thymol, all diminished PRV intracellular proliferation in vitro. Carvacrol exhibited the most potent anti-PRV effect, serving as the primary contributor to oregano essential oil's anti-PRV activity. The mechanisms underlying carvacrol's anti-PRV properties include the upregulation of cytokines TNF-α, IFN-ß, IFN-γ, IL-12, and the inhibition of PRV-induced apoptosis in BHK-21 cells. CONCLUSIONS: Our study provides an effective drug for the prevention and control of PRV infection.

Inhibitory effect and mechanism of oregano essential oil on Listeria monocytogenes cells, toxins and biofilms.

Listeria monocytogenes (L. monocytogenes) is a prevalent foodborne pathogen with a remarkable capacity to form biofilms on utensil surfaces. The Listeriolysin O (LLO) exhibits hemolytic activity, which is responsible for causing human infections. In this study, we investigated the inhibitory effect and mechanism of oregano essential oil (OEO) on L. monocytogenes, evaluated the effects on its biofilm removal and hemolytic activity. The minimum inhibitory concentration (MIC) of OEO against L. monocytogenes was 0.03 % (v/v). L. monocytogenes was treated with OEO at 3/2 MIC for 30 min the bacteria was decreased below the detection limit (10 CFU/mL) in PBS and TSB (the initial bacterial load was about 6.5 log CFU/mL). The level of L. monocytogenes in minced pork co-cultured with OEO (15 MIC) about 2.5 log CFU/g lower than that in the untreated group. The inhibitory mechanisms of OEO against planktonic L. monocytogenes encompassed perturbation of cellular morphology, elevation in reactive oxygen species levels, augmentation of lipid oxidation extent, hyperpolarization of membrane potential, and reduction in intracellular ATP concentration. In addition, OEO reduced biofilm coverage on the surface of glass slides by 62.03 % compared with the untreated group. Meanwhile, OEO (1/8 MIC) treatment reduced the hemolytic activity of L. monocytogenes to 24.6 % compared with the positive control. Molecular docking suggested carvacrol and thymol might reduce the hemolytic activity of L. monocytogenes. The results of this study demonstrate that OEO exhibits inhibitory effects against L. monocytogenes, biofilms and LLO, which had potential as natural antimicrobial for the inhibition of L. monocytogenes.

Chemical and Bioactive Evaluation of Essential Oils from Edible and Aromatic Mediterranean Lamiaceae Plants.

The Lamiaceae family, which includes several well-known aromatic plants, is scientifically relevant due to its essential oils (EOs). In this work, four EOs from Mediterranean species, namely Origanum vulgare L., Rosmarinus officinalis L., Salvia officinalis L., and Thymus vulgaris L., were evaluated for their volatile profiles and the biological activity in vitro to assess their potential use in the food and cosmetic sector. GC/MS analysis revealed dominant compounds, such as carvacrol, thymol, and eucalyptol. Regarding biological action, the samples exhibited antioxidant, cytotoxic, anti-inflammatory, antimicrobial, and antifungal activities, with O. vulgare and T. officinalis standing out. T. vulgaris showed the lowest EC50 in the reducing power assay, and O. vulgare had the lowest EC50 in the DPPH assay. Most EOs also displayed excellent anti-inflammatory responses and antifungal properties, with O. vulgare and T. vulgaris also demonstrating antibacterial activity. All EOs from Mediterranean species showed cytotoxicity against tumoral cell lines. Overall, the selected EOs stood out for their interesting bioactivities, with the obtained results underscoring their potential as natural preservatives and bioactive agents in various industrial applications, including food, pharmaceuticals, and cosmetics.

Comprehensive Bio-Screening of Phytochemistry and Biological Capacity of Oregano (Origanum vulgare) and Salvia triloba Extracts against Oral Cariogenic and Food-Origin Pathogenic Bacteria.

This study utilized phytochemical screening to conduct the qualitative analysis of plant extracts, aiming to identify various classes of secondary metabolites. Moreover, the antibacterial activity of different types of Oregano vulgare and Salvia triloba extracts was determined. To achieve the aim of this study, aqueous, ethanolic, and enzymatic extracts were prepared and screened for phytochemical capacity and antioxidant activities. The determination of the antibacterial activity included phenotypic screening of antibiotic susceptibility pattern of oral and food pathogenic bacterial strains, determination of the minimum inhibitory concentration and minimum bactericidal concentration-via microdilution broth test and in vitro valuation of antibacterial efficacies-of the anti-biofilm properties of the studied herbal extractions. Results: Our study evaluated the phytochemical composition and the antioxidant, antibacterial, and anti-biofilm properties of O. vulgare and S. triloba extracts. The analyzed samples contained bioactive compounds, such as phenolics and flavonoids, contributing to the observed strong antioxidant effect. Furthermore, they exhibited notable activity against oral biofilm formation and demonstrated significant antibacterial efficacy against dental caries' microorganisms as well as food pathogens. Despite methodological variations, all extracts showed significant antioxidant capacity and promising antibacterial activity against various pathogens, including resistant strains, while also inhibiting biofilm formation. Although limited to two plant species and facing methodological constraints, this study lays the groundwork for future research, indicating the therapeutic potential of O. vulgare and S. triloba extracts. Further exploration is needed to report on underlying mechanisms and validate efficacy through clinical trials.

Effective concentration of herbal anaesthetics Origanum vulgare L. oil and its effects on stress parameters in Nile tilapia (Oreochromis niloticus).

BACKGROUND: Using anaesthetics is an important application in aquaculture especially where the fish transportation, vaccination, grading, sorting activities and many other handling operations have been conducted during the different stages of production periods in the farms or hatcheries. OBJECTIVES: This study aimed to evaluate the efficacy of oregano essential oil (OO) as an anaesthetic for Nile tilapia and to determine the optimal concentration and post-application stress effects compared to clove oil (CO). METHODS: Nile tilapia juveniles were exposed to different concentrations of OO (20-40-60-80-100 mg L-1) and CO (50 mg L-1) for different time periods to determine the optimal concentration and exposure time. After the effective concentration of OO was determined, in the second experiment, stress parameters (glucose, plasma cortisol) were analysed after 0, 2, 6, 12 and 24 h of application. The results compared to the control group and CO results. RESULTS: The study found that OO which has carvacrol compound higher than 78% was an efficient anaesthetic for Nile tilapia, and the effective concentration was found to be 60 mg L-1. No significant differences were found between opercular beats in any concentration of OO and CO. Basal glucose level in blood without anaesthesia application and recorded at 39.33 mg dL-1 and significantly lower than OO and CO at first two sampling points, 0 and 2 h (p < 0.05). According to plasma cortisol level results, although CO experimental group showed secondary stress response at 12 h (17.91 ± 4.21 ng mL-1), OO and CO group cortisol levels decreased at 24 h after anaesthesia application 7.13 ± 0.14and 7.01 ± 0.54 ng mL-1, respectively, below the control group cortisol concentration (12.28 ± 1.81 ng mL-1). CONCLUSIONS: These findings have important implications for the aquaculture industry as the use of OO as an anaesthetic could reduce the stress and mortality associated with traditional anaesthetics. Further research is needed to evaluate the efficacy of OO as an anaesthetic agent for other fish species and to determine the optimal concentration and exposure time for different species.

Assessment of antibacterial activity, modes of action, and synergistic effects of Origanum vulgare hydroethanolic extract with antibiotics against avian pathogenic Escherichia coli.

This study evaluates the antibacterial effectiveness of Origanum vulgare hydroethanolic extract, both independently and in combination with antibiotics, against Escherichia coli strains associated with avian colibacillosis-a significant concern for the poultry industry due to the rise of antibiotic-resistant E. coli. The urgent demand for new treatments is addressed by analyzing the extract's phytochemical makeup via High-Performance Liquid Chromatography (HPLC), which identified sixteen phenolic compounds. Antibacterial activity was determined through agar diffusion and the measurement of minimum inhibitory and bactericidal concentrations (MIC and MBC), showing moderate efficacy (MIC: 3.9 to 7.8 mg/mL, MBC: 31.2 to 62.4 mg/mL). Combining the extract with antibiotics like ampicillin and tetracycline amplified antibacterial activity, indicating a synergistic effect and highlighting the importance of combinatory treatments against resistant strains. Further analysis revealed the extract's mechanisms of action include disrupting bacterial cell membrane integrity and inhibiting ATPase/H+ proton pumps, essential for bacterial survival. Moreover, the extract effectively inhibited and eradicated biofilms, crucial for preventing bacterial colonization. Regarding cytotoxicity, the extract showed no hemolytic effect at 1 to 9 mg/mL concentrations. These results suggest Origanum vulgare extract, particularly when used with antibiotics, offers a promising strategy for managing avian colibacillosis, providing both direct antibacterial benefits and moderating antibiotic resistance, thus potentially reducing the economic impact of the disease on the poultry industry.

Antimicrobial potential of oregano essential oil vehiculated in Pickering cellulose nanofibers-stabilized emulsions.

Essential oils show several biological properties, such as antimicrobial activity, but have limitations regarding their availability and stability. To maximize their antimicrobial effect and protection against environmental conditions, Pickering-type emulsions were used to vehiculate oregano essential oil (OEO) using cellulose nanofibers (CNF) as emulsion stabilizer. Enzymatic hydrolysis was used to produce CNF from a food industry waste (cassava peel), obtaining an environmentally sustainable emulsion stabilizer. It was evaluated how the different properties of the nanofibers affected the stability of the emulsions. Furthermore, the composition of the dispersed phase was varied (different ratios of OEO and sunflower oil-SO) in view of the target application in biodegradable active coatings. Even at very low concentration (0.01 % w/w), CNF was able to form kinetically stable emulsions with small droplet sizes using oil mixtures (OEO + SO). The stabilization mechanism was not purely Pickering, as there was a reduction in interfacial tension. Excellent antimicrobial activity was observed against bacteria and the fungus Alternaria alternata, demonstrating the ability to apply these emulsions in active systems such as coatings and films. An improvement in the stability of emulsions was observed when using a mixture of oils, which is extremely advantageous considering costs and stability to heat treatments, since the desired antimicrobial activity is maintained for the final application.

Preparation, characterization, and coating effect of bio-active nano-emulsion based on combined plant essential oils on quality of grass carp fillets.

This study aimed to develop a satisfactory essential oil (EO) nano-emulsion through high pressure microjet technology and explore its physiochemical properties and synergistic coating effects on grass carp fillets. The optimal conditions for oregano/litsea cubeba (6:4, wt%/wt%) nano-emulsion were shown to be 80 s high pressure microjet pretreatment time, 9000 lb per square inch pretreatment pressure, 6 % oil phase, and 3:2 Km (mass ratio of surfactant to co-surfactant). The obtained nano-emulsion exhibited 100.42 ± 0.96 nm oil diameter at 4 °C after 15-day storage, coupled with high stability after centrifugation, freeze-thaw and heating treatment. Compared with untreated samples at day 6 storage, the nano-emulsion-treated grass carp fillets exhibited improved textural properties, higher water-holding capacity (74.23 % ± 0.80 %), lower total volatile basic nitrogen (TVB-N, 13.46 ± 0.30 mg/100g)/thiobaric acid (TBA,0.43 ± 0.02 mgMDA/100g), and lower total viable spoilage bacteria count (4.98 ± 0.21 lgCFU/g). This study facilitates understanding the combined EOs nano-emulsion on improving the shelf life of grass carp fillets.

Flow cytometry: Unravelling the real antimicrobial and antibiofilm efficacy of natural bioactive compounds.

Flow cytometry (FCM) provides unique information on bacterial viability and physiology, allowing a real-time early warning antimicrobial and antibiofilm monitoring system for preventing the spread risk of foodborne disease. The present work used a combined culture-based and FCM approach to assess the in vitro efficacy of essential oils (EOs) from condiment plants commonly used in Mediterranean Europe (i.e., thyme EO, oregano EO, basil EO, and lemon EO) against planktonic and sessile cells of food-pathogenic Listeria monocytogenes 56 LY, and contaminant and alterative species Escherichia coli ATCC 25922 and Pseudomonas fluorescens ATCC 13525. Evaluation of the bacterial response to the increasing concentrations of natural compounds posed FCM as a crucial technique for the quantification of the live/dead, and viable but non-culturable (VBNC) cells when antimicrobial agents exert no real bactericidal action. Furthermore, the FCM results displayed higher numbers of viable bacteria expressed as Active Fluorescent Units (AFUs) with a greater level of repeatability compared with outcomes of the plate-count method. Overall, accurate counting of viable microbial cells is a critically important parameter in food microbiology, and flow cytometry provides an innovative approach with high-throughput potential for applications in the food industry as "flow microbiology".

Essential oil of oregano (Origanum vulgare L.) reduces infection and proliferation of Toxoplasma gondii in BeWo cells with induction of autophagy and death of tachyzoites through a mechanism similar to necrosis.

Toxoplasmosis poses a global health threat, ranging from asymptomatic cases to severe, potentially fatal manifestations, especially in immunocompromised individuals and congenital transmission. Prior research suggests that oregano essential oil (OEO) exhibits diverse biological effects, including antiparasitic activity against Toxoplasma gondii. Given concerns about current treatments, exploring new compounds is important. This study was to assess the toxicity of OEO on BeWo cells and T. gondii tachyzoites, as well as to evaluate its effectiveness in in vitro infection models and determine its direct action on free tachyzoites. OEO toxicity on BeWo cells and T. gondii tachyzoites was assessed by MTT and trypan blue methods, determining cytotoxic concentration (CC50), inhibitory concentration (IC50), and selectivity index (SI). Infection and proliferation indices were analyzed. Direct assessments of the parasite included reactive oxygen species (ROS) levels, mitochondrial membrane potential, necrosis, and apoptosis, as well as electron microscopy. Oregano oil exhibited low cytotoxicity on BeWo cells (CC50: 114.8 µg/mL ± 0.01) and reduced parasite viability (IC50 12.5 ± 0.06 µg/mL), demonstrating 9.18 times greater selectivity for parasites than BeWo cells. OEO treatment significantly decreased intracellular proliferation in infected cells by 84% after 24 h with 50 µg/mL. Mechanistic investigations revealed increased ROS levels, mitochondrial depolarization, and lipid droplet formation, linked to autophagy induction and plasma membrane permeabilization. These alterations, observed through electron microscopy, suggested a necrotic process confirmed by propidium iodide labeling. OEO treatment demonstrated anti-T. gondii action through cellular and metabolic change while maintaining low toxicity to trophoblastic cells.

Impact of packaging atmosphere, oregano essential oil, and storage temperature on cold-adapted Salmonella Enteritidis and Salmonella Typhimurium on ready-to-eat smoked turkey.

The hazard of diseases created by S. Enteritidis and S. Typhimurium is relatively high in turkey meat products. Combinations of preservation methods are utilized in many strategies, such as mild heat with decreased water activity, a changed atmosphere, refrigerated storage, and decreased heat treatment with some acidification. Within the domain of ready-to-eat food technology, a range of preservation methods are typically utilized to enhance shelf life, such as applying mild heat in tandem with reduced water activity, employing modified atmosphere packaging, utilizing refrigerated storage, and utilizing reduced heat treatment combined with acidification. This investigation aimed to determine how S. Enteritidis and S. Typhimurium grew when sliced ready-to-eat smoked turkey (RTE-SM) was stored at 0, 5, 10, and 15°C for various periods. The study also examined the effects of modified atmosphere packaging (MAP) (40% CO2 and 60% N2) and VP on these growth patterns. Total viable count (TVC), lactic acid bacteria (LAB), pH, and redox potential levels were determined. The control experiment on RTE-SM showed no Salmonella growth within 30 d of storage at any temperature. This indicated that the RTE-SM in use did not initially contain S. Typhimurium and S. Enteritidis. Results indicated that the storage of RTE-SM using a combination of VP, MAP, and MAPEO with storage at 0 and 5°C did not allow for the pathogen to grow throughout storage. In comparison, at 10 and 15°C after one day, which allowed for minor growth (0.17-0.5 log CFU/g)? In contrast, at 0 and 5°C, Salmonella survives until the end of storage (173 d). However, the combination of MAPEO with the same storage temperatures achieved the elimination of the pathogen in the meat after 80 d. The combination of both packaging systems with high temperatures (10 or 15°C) allowed for the multiplication and growth of the bacterium through the product's shelf life of more than 1 log CFU/g. Thus, a combination of MAP or MAPEO with low storage temperatures (0 or 5°C) inhibited the growth of the pathogen.