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The aim of this study was to analyse the essential oil of Lavandula dentata from Algeria and to test the antioxidant and antimicrobial properties of this plant. The essential oil (EO) (57 constituents) included mainly α-pinene, β-pinene, nopinone, linalool, cryptone, and limonene. The plant polyphenolic contents and the antioxidant activity were determined. The antimicrobial effect of the EO and the methanolic extract (ME) was assessed against referenced and clinical bacterial strains, and also foodborne fungal isolates. The EO minimal inhibitory concentration (MIC) values varied from 0.25 to 4 mg/mL and minimal bactericidal concentrations (MBCs) were less than 8 mg/mL except for S. aureus, clinical Klebsiella, S. epidermidis, and B. subtilis. The mould strains were significantly inhibited by the EO (87.50% to 88.33%). The MIC values were 3.60–15.62 mg/mL and 0.5–4 mg/mL for ME and EO, respectively. The minimal fungicidal concentration (MFC) values ranged from 31 to 125 mg/mL and from 2 to 8 mg/mL for ME and EO, respectively. [ABSTRACT FROM AUTHOR]

Recent reports of P. olsonii causing postharvest rot of cherry tomatoes emphasize the need for effective strategies to prolong fruit shelf life. This study is the first to explore the use of essential oils (EOs), recognized for their antimicrobial properties, as a potential method to prevent postharvest losses from P. olsonii. Antifungal activity was tested for ten EOs at a concentration of 625 μL/L using the vapor diffusion method. Thyme, wild thyme, savory, oregano, and marjoram completely inhibited fungal growth over 14 days. Thyme EO, at a minimum inhibitory concentration (MIC) of 250 μL/L, fully inhibited all strains, while oregano, wild thyme, and savory were effective at 500 μL/L. Marjoram EO showed weaker activity. The lowest IC90 values, ranging from 35.72 to 162.72 μL/L, were estimated for thyme and oregano. In cherry tomatoes, oregano EO completely halted P. olsonii growth at 250 μL/L; thyme was effective for seven days; wild thyme and savory for two days. Thyme EO prevented P. olsonii spore germination at 500 μL/L for seven days, though germination occurred at half that concentration. The IC90 values varied between 256.2 and 138.7 μL/L depending on the strain. The vapor phase of EOs at 125 μL/L influenced the sensory characteristics of cherry tomatoes; however, for thyme and oregano, this effect was not negative due to their culinary association with tomato flavor. The selected EOs could be used to control and prevent postharvest fruit losses, but further research is needed to optimize their application. [ABSTRACT FROM AUTHOR]

Gamma-terpinene (γ-TPN) is a cyclohexane monoterpene isolated from plant essential oils, such as tea tree (Melaleuca alternifolia), oregano (Origanum vulgare), rosemary (Rosmarinus officinalis L.), thyme (Thymus vulgaris Marchand), and eucalyptus (Eucalyptus sp.). Terpenes are widely studied molecules pharmacologically active on the cardiovascular system, hemostasis, and antioxidant actions. Herein, it was investigated the cytotoxic and antiplatelet activity of γ-TPN using different non-clinical laboratory models. For in silico evaluation, the PreADMET, SwissADME, and SwissTargetPrediction softwares were used. Molecular docking was performed using the AutoDockVina and BIOVIA Discovery Studio databases. The cytotoxicity of γ-TPN was analyzed by the MTT assay upon normal murine endothelial SVEC4-10 and fibroblast L-929 cells. Platelet aggregation was evaluated with platelet-rich (PRP) and platelet-poor (PPP) plasma from spontaneously hypertensive rats (SHR), in addition to SVEC4-10 cells pre-incubated with γ-TPN (50, 100, and 200 µM) for 24 h. SHR animals were pre-treated by gavage with γ-TPN for 7 days and divided into four groups (negative control, 25, 50, and 100 mg/kg). Blood samples were collected to measure nitrite using the Griess reagent. Gamma-TPN proved to be quite lipid-soluble (Log P = +4.50), with a qualified profile of similarity to the drug, good bioavailability, and adequate pharmacokinetics. It exhibited affinity mainly for the P2Y12 receptor (6.450 ± 0.232 Kcal/mol), moderate cytotoxicity for L-929 (CC50 = 333.3 µM) and SVEC 4-10 (CC50 = 366.7 µM) cells. The presence of γ-TPN in SVEC 4-10 cells was also able to reduce platelet aggregation by 51.57 and 44.20% at lower concentrations (50 and 100 µM, respectively). Then, γ-TPN has good affinity with purinergic receptors and an effect on the reversal of platelet aggregation and oxidative stress, being promising and safe for therapeutic targets and subsequent studies on the control of thromboembolic diseases. [ABSTRACT FROM AUTHOR]

A novel, simple, rapid, and non-expensive analytical method based on square wave voltammogram at Pt-microelectrode coupled with partial least square multivariate calibration was used for the simultaneous quantitation of thymol (THY) and carvacrol (CAR) in thyme and oregano essential oils. Results demonstrated that the multivariate calibration method successfully exploited the first-order advantage, rendering highly satisfactory quantitative figures (average recoveries not statistically different than 100%). Moreover, the results agree well with those obtained from the official analytical method. Last, the method's environmental sustainability was asserted using the AGREE metric, highlighting its eco-friendly nature. More importantly, the proposed analytical procedure does not require previous sample preparation or electrode surface modification. The results underscore the suitability of the method for determining THY and CAR in essential oils at low concentrations (LOD ~ 7.6 µM) with REP% below 5.6%, meeting the requirements of the green analytical chemistry. [ABSTRACT FROM AUTHOR]

Onychomycosis is a common fungal nail infection for which new antifungals are needed to overcome antimicrobial resistance and the limitations of conventional treatments. This study reports the development of antifungal nail lacquers containing oregano essential oil (OEO), rosemary essential oil (REO), and biogenic silver nanoparticles (bioAgNPs). The formulations (F) were tested against dermatophytes using agar diffusion, ex vivo nail infection, and scanning electron microscopy techniques. They were evaluated for their pharmacotechnical characteristics and by FTIR-PAS to assess permeation across the nail. F-OEO and F-OEO/bioAgNPs were promising candidates for the final nail lacquer formulation, as they permeated through the nail and showed antifungal efficacy against dermatophytes-contaminated nails after 5 days of treatment. Treated nails exhibited decreased hyphae and spores compared to the untreated control; the hyphae were atypically flattened, indicating loss of cytoplasmic content due to damage to the cytoplasmic membrane. The formulations were stable after centrifugation and thermal stress, maintaining organoleptic and physicochemical characteristics. Both F-OEO and F-OEO/bioAgNPs had pH compatible with the nail and drying times (59–90 s) within the reference for nail lacquer. For the first time, OEO and bioAgNPs were incorporated into nail lacquer, resulting in a natural and nanotechnological product for onychomycosis that could combat microbial resistance. [ABSTRACT FROM AUTHOR]

The experiment aimed to study the effects of oregano essential oil on the growth performance, immune function, and slaughter performance of Ward 168 broilers. A total of 1 000 one-day-old Ward 168 broilers were selected and randomly divided into two groups, with five replicates per group and 100 chickens per replicate. The control group was fed a basic diet, while the experimental group was fed the basic diet supplemented with 300 g/t of oregano essential oil. The trial period was 45 days. The results showed that compared to the control group, the feed-to-gain ratio of the experimental group broilers was significantly reduced (P<0.05), and the semi-eviscerated yield, fully eviscerated yield, breast muscle rate, and leg muscle rate were all significantly increased (P<0.05). Compared to the control group, the levels of serum IgA and IgM in the experimental group broilers, as well as the activities of GSH-Px, SOD, and T-AOC, were all significantly or extremely increased (P<0.05 or P<0.01), while the levels of IL-1β, IFN-γ, and MDA were significantly or extremely reduced (P<0.05 or P<0.01). Compared to the control group, the organ index of the spleen in the experimental group broilers was significantly increased (P<0.05), and the organ index of the bursa of Fabricius was extremely increased (P<0.01). The study indicates that the addition of 300 g/t oregano essential oil to the diet can improve the growth performance, immune capacity, antioxidant performance, and slaughter performance of broilers. [ABSTRACT FROM AUTHOR]

Lemon bee balm (Monarda citriodora Cerv. ex-Lag) is a noble industrial medicinal and aromatic plant species, which is used as digestive, antifungal, anti-inflammatory and menstrual irregularity remedies in traditional medicine. It is a common source of thymol and other active constituents with recognized antimicrobial properties. A multilocation field trial was performed to evaluate essential oil (EO) yield stability, secondary metabolites and economic returns in eight diverse geographical environment conditions (GEC) in India. The secondary metabolites viz., essential oil content and oil yield were found to be highest in tropical and sub-tropical regions. The essential oil content was found to be higher in inflorescence part at all the experimental sites and found to be highest (0.85±0.21%) at BR-JALAUN. The highest EO yield (130.25±3.25 kg ha−1), net return (Rs. 1,22,125.00±245.21 ha−1) and benefit cost (B:C) ratio (2.67±0.17) was recorded at FFDC-KANNAUJ. The thymol content percentage was found to be highest on physiological maturity (>95% flowering) [PM] and on 75% flowering [FS-II] and it began to decline on seed formation stage at all the experimental sites. The significantly highest thymol content percentage was found on PM (86.65±3.91%) and on FS-II (84.21±3.78%) at TBR-JHANSI. On the basis of the gas chromatography and mass spectrophotometry analysis, twenty constituents were isolated. The inflorescence EO contains more thymol than the EO from leaves with stem which in turn was characterized by a higher content of p-cymene, γ-terpinene, carvacrol, α-phellandrene, α-pinene, myrcene, α-terpinene, citral and β-caryophyllene. [ABSTRACT FROM AUTHOR]

Multidrug-resistant (MDR) Gram-negative bacteria remain a global public health issue due to the barrier imposed by their outer membrane and their propensity to form biofilms. It is becoming imperative to develop new antibacterial strategies. In this context, this study aims to evaluate the antibacterial efficacy of Origanum vulgare essential oil (OEO), alone and in combination with antibiotics, as well as its antibiofilm action against multidrug-resistant Gram-negative strains. OEO components were identified by gas chromatography-mass spectrometry (GC-MS), and antibacterial activity was assessed using the agar diffusion test and the microdilution method. Interactions between OEO and antibiotics were examined using the checkerboard method, while antibiofilm activity was analyzed using the crystal violet assay. Chemical analysis revealed that carvacrol was the major compound in OEO (61.51%). This essential oil demonstrated activity against all the tested strains, with inhibition zone diameters (IZDs) reaching 32.3 ± 1.5 mm. The combination of OEO with different antibiotics produced synergistic and additive effects, leading to a reduction of up to 98.44% in minimum inhibitory concentrations (MICs). In addition, this essential oil demonstrated an ability to inhibit and even eradicate biofilm formation. These results suggest that OEO could be exploited in the development of new molecules, combining its metabolites with antibiotics. [ABSTRACT FROM AUTHOR]

A functional edible film containing Pickering emulsion (PE) loaded with oregano essential oil (OEO) was developed. The sustained release of OEO in muffins significantly delayed muffin decay at 25°C (p < 0.05). According to the influence of oxygen permeability, antibacterial activity and mechanical properties of the active film, the optimum preparation conditions of PE were determined by orthogonal experiment. Peroxide values (POVs), total viable count (TVC) and yeast and mould count (YMC) were significantly lower compared with the blank group. On Day 6, the POV in the experimental group was 63% that of the blank group. TVC and YMC were 3.20 and 1.86 lg CFU/g on Day 9, respectively (TVC ≤ 1500 CFU/g; YMC ≤ 100 CFU/g), extending muffins shelf life to 6–7 days in practical preservation at 25°C. Thus, the edible PE loaded with OEO film provided sustained release, effectively slowing muffin quality deterioration and extending shelf life, making it a promising choice for future high‐fat food packaging. [ABSTRACT FROM AUTHOR]

This study explores the antifungal efficacy of oregano and cumin essential oils against Aspergillus flavus in almonds. Our findings revealed that oregano oil at a concentration of 150 µg l-1 was significantly more effective in inhibiting Aspergillus flavus growth than cumin oil at 300 µg l-1. After a 10-day incubation period, almonds treated with oregano oil exhibited an average fungal infection rate of just 5%, compared to 58% for cumin oil-treated almonds, and a high 95% in untreated control samples. This indicates a remarkable 94% reduction in Aspergillus flavus growth for oregano oil-treated almonds in comparison to the control group. In contrast, cumin oil showed a 39% decrease in fungal contamination relative to the control, demonstrating its lesser but notable antifungal potential. The study also found that almonds with dry peel had lower mold contamination rates than those with green peel when treated with these essential oils, highlighting the protective role of the hardened endocarp. Thirteen panellists rated almond qualities using a 9-point scale. Cumin oil treated almonds had higher aroma and flavor ratings than oregano oil and control almonds. Cumin offered a spicy aroma and harmonious flavor, while oregano had a medicinal aroma and bitter taste. Cumin effectively inhibited fungal growth and maintained almond quality. Sensory analysis showed a consumer preference for the aroma and taste of cumin oil-treated almonds, despite the lower antifungal efficacy. Overall, this research underscores the potential of oregano and cumin essential oils as sustainable alternatives to synthetic preservatives in controlling Aspergillus flavus infection in almonds post-harvest.

Red oregano (Origanum vulgare L. subsp. vulgare) is native to the mountainous slopes of Albania, thriving at altitudes ranging from 400 to 1300 m above sea level. The aerial components of oregano have been found to address a spectrum of health concerns. However, this subspecies presents intriguing characteristics that require comprehensive exploration and analysis. This study extensively analyzes the ex −situ collection of various genotype populations of red oregano in Albania. Essential oils were extracted by employing the hydrodistillation method. At the same time, their chemical analyses were carried out using gas chromatography coupled with a flame ionization detector (GC−FID) and gas chromatography coupled with a mass−spectrometer detector (GS−MS). We employed two statistical techniques, namely hierarchical cluster analysis (HCA) and principal component analysis (PCA), which allowed for a comprehensive examination of the relationships within the data set and more profound insights into the compositional patterns and interrelationships within the essential oils to be gained. The results revealed significant qualitative distinctions at the intraspecific level, particularly for sesquiterpenes, of populations originating from seven diverse geographic locations. The study's findings enhance our understanding of the chemical composition of Albania's red oregano and its chemical variation among different populations, which will potentially contribute to identifying the most suitable clones for breeding programs within red oregano populations. [ABSTRACT FROM AUTHOR]

Summary: Adding natural antimicrobials such as essential oils (EOs) to alginate coatings on fruits provides an antifungal effect and a semipermeable water vapour barrier. This work aims to evaluate the antifungal effect of Lippia berlandieri S. (Mexican oregano) EO incorporated into alginate to coat tomato stems inoculated with Penicillium commune, Fusarium spp., or Cladosporium herbarum. Alginate films and coatings with EO concentrations (0%, 0.25%, 0.75%, 1%, 2%, or 4% v/v) were prepared to evaluate their properties (physical, mechanical, and water vapour transmission rates) as well as their effect on mould growth on tomato stems for 28 days during refrigerated storage. Mould growth was described with probabilistic and time‐to‐growth predictive models. Two treatment types were assessed (tomato inoculated and coated, TIC, and tomato coated and inoculated, TCI) to provide information about the moment of mould contamination (before or after coating). EO concentration influenced the alginate films' physical, mechanical, and barrier properties. Testing the coatings against moulds revealed varying inhibitory effects. Fusarium spp. exhibited the highest resistance, while C. herbarum was the most susceptible. The predictive models appropriately described the probability of growth or the time‐to‐growth of the studied moulds, identifying critical concentrations of oregano EO needed to inhibit mould growth effectively. The findings suggest that alginate coatings with oregano EO can serve as a natural and effective antifungal treatment for tomatoes, offering insights into optimal concentrations and application methods for extended shelf life. [ABSTRACT FROM AUTHOR]

Sunflower oil and peanuts are susceptible to oxidation reactions during the frying process. This study aimed to evaluate the efficacy of hop and oregano essential oils in protecting sunflower oil and peanuts during frying. The sunflower oil was enriched with oregano and hop essential oils (0.02% w/w). These treatments were compared to sunflower oil enriched with BHT (0.02% w/w). All treatments were subjected to a temperature of 170 °C for 8 h. Samples were collected at 0, 2, 4, and 8 h. Chemical oxidation indicators, oxidation volatile compounds, and 2,5-dimethyl pyrazine were measured. Also, a descriptive sensory analysis of fried peanuts was carried out. Oregano and hop essential oils enhanced the oxidative stability of the sunflower oil, while preventing the development of undesirable flavours in the fried peanuts. However, this protection led to the formation of 2,5-dimethyl pyrazine, which is responsible for desirable flavours. [ABSTRACT FROM AUTHOR]

The main objective of this study was to evaluate the effects of the antagonistic Bacillus subtilis and oregano essential oil (EO) on decay caused by Botrytis cinerea, shelf life, and some quality parameters of sweet cherry (Prunus avium cv. Takdaneh Mashhad). The fruit were inoculated with suspension of pathogenic fungus (1 × 105 spore mL−1), and then were treated with the antagonist bacterial strains at 1 × 108 CFU mL−1 and the EO at 0. 250, 500, 750, and 1000 µL/L. Treated fruit were stored at 0 ± 1 °C for 30 d. Quality parameters including firmness, weight loss, antioxidant activity, phenylalanine ammonia-lyase enzyme activity, marketability, color, total anthocyanins, and decay extension rate were evaluated after 0, 15, and 30 days of storage. The results showed that with an increase in storage time the quality of cherry fruit is significantly decreased and EO and Bacillus treatments significantly maintain fruit marketability, antioxidant activity and anthocyanins content. EO in at 750 µL/L in combination with Bacillus bacteria, significantly reduced fungal decay, retained quality and increased shelf life of sweet cherries. Therefore, the use of Bacillus bacteria and oregano essential oil can be considered as a promising environmental friendly alternative method for maintaining the sweet cherry fruit quality during storage. [ABSTRACT FROM AUTHOR]

Antimicrobial low‐density polyethylene (LDPE) films were developed by adding 0%, 0.5%, 1.0%, 2.5% and 5.0% (w/w) of Mexican oregano essential oil (OEO) or potassium sorbate (PS) as a positive antifungal control to inhibit the growth of Penicillium expansum, Penicillium citrinum and Aspergillus niger in vitro. Three methods of adding OEO in LDPE were evaluated; the best OEO yield in film was achieved when OEO was incorporated after laminating (88%); otherwise, when added into cool‐melting resin, OEO lost up to 91.5% from LDPE and completely volatilized (>99%) when combined with the resin before melting. PS yields in LDPE film were > 88% when incorporated into cool‐melted resin. Antimicrobial films with 2.5% or 5.0% (w/w) OEO or PS delayed the growth of P. expansum and P. citrinum for up to 4–5 days, and for A. niger, only films with 5.0% of OEO retarded its growth for 5 days. The modified Gompertz model was used to describe mould growth response, obtaining the parameters A (maximum growth), μm (maximum growth rate) and λ (lag phase), which correctly fit the data. P. citrinum was the most sensitive mould, and A. niger was the most resistant to the tested antimicrobials. The addition of antimicrobial agents significantly (p < 0.05) impacted the physical and mechanical properties of the LDPE films, wherein thickness and puncture strength were increased, and the colour changed (reducing the transparency and promoting the yellowness). In contrast, the water vapour transmission rate was dropped only by incorporating PS. [ABSTRACT FROM AUTHOR]

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. [ABSTRACT FROM AUTHOR]

Fasciolosis is a worldwide distribution zoonosis that causes great damage in ruminant breeding and has the aquatic mollusc Pseudosuccinea columella as an intermediate host. Synthetic molluscicides are the most used for control; however, they are harmful to fauna and flora. Therefore, this study aimed to evaluate the effect of essential oils from Thymus vulgaris, Origanum vulgare, and terpene carvacrol, on adult molluscs and eggs of P. columella. Analysis of EO volatile components was carried out on a gas chromatograph equipment coupled with mass spectrometry selective detector. The studied components were diluted in concentrations of 10, 20, 40, 60, 80 and 100 ppm, and it was observed that O. vulgare at concentrations of 60, 80 and 100 ppm, carvacrol at the concentrations of 80 and 100 ppm, and T. vulgaris at a concentration of 80 ppm led to 100% mortality of molluscs. All concentrations the substances tested showed 100% ovicidal activity. [ABSTRACT FROM AUTHOR]

The rice weevil (Sitophilus oryzae L.) and the cigarette beetle (Lasioderma serricorne F.) are primary and secondary insect pests that cause significant damage to stored grains and commodities. The goal of this study was to evaluate the physicochemical properties and insecticidal activity of Origanum vulgare (L.) (OV) and Laurus nobilis (L.) (LN) essential oils (EOs) in polymeric nanoparticles (PNs) prepared using the melt dispersion technique with polyethylene glycol (PEG 6000) as the matricidal material. In PNs, the monocyclic monoterpenes were retained in high proportions after encapsulation. Physicochemical analyses revealed that OV and LN PNs had mean sizes of 295 and 429 nm, respectively, with a loading efficiency of almost 90%, and a polydispersity index ≤ 0.25 (monodisperse samples). Against Sitophilus oryzae, only OV PN significantly enhanced the lethal effect of EO, whereas on L. serricorne, both PNs. It was demonstrated that, on both pests, OV EO and its PNs increased their sensitivity to pyrethroids, whereas LN oil and their PNs promote this effect only on S. oryzae. The PNs of OV and LN altered the nutritional physiology and behavior variables of both stored product pest and prolonged the repellent effect of the EOs on S. oryzae and L. serricorne up to 60 and 48 h. Ecotoxicity bioassays demonstrated that OV and LN EOs and their PNs were harmless to terrestrial non-target organisms and had slight negative effects on aquatic non-target organisms. Finally, PNs did not affect viability of primary osteoblast cells. [ABSTRACT FROM AUTHOR]

Simple Summary: The impact of livestock on climate change has prompted animal nutrition researchers to reassess ruminant feeding strategies that minimize negative repercussions on the ecosystem. Essential oils (EOs), derived from natural plant extracts, have emerged as promising substances capable of inhibiting rumen methanogenesis. This study elucidated the effects of oregano and white thyme EOs on in vivo rumen methane emissions and rumen parameters in Nellore beef cattle. In contrast to results obtained through in vitro methods, our in vivo results indicated that oregano and white thyme EOs included in the diet at 3 mL/kg dry matter were not effective in reducing rumen methane emissions. Essential oils (EOs), as rumen additives, decreased CH4 emissions in in vitro trials but results from in vivo studies are still limited. We investigated the effects of Origanum vulgare (OEO) and Thymus vulgaris (TEO) EOs on in vivo methane emissions from Nellore beef cattle. Six adult rumen-cannulated Nellore cattle were used in a double 3 × 3 Latin square design. Treatments consisted of three diets containing either 3 mL OEO per kg of concentrate, 3 mL TEO/kg of concentrate, or no EO addition. The experimental period consisted of three 21 d feeding periods and methane production was measured using the sulfur hexafluoride (SF6) technique from Day 16 to Day 21 of each feeding period. Intake, total apparent digestibility (dry matter as well as neutral and acid detergent fiber), and rumen parameters (pH, ammoniacal nitrogen concentration, and short-chain fatty acids) were also evaluated. The EOs did not decrease CH4 emissions and had no effect on rumen parameters. [ABSTRACT FROM AUTHOR]

Simple Summary: Simple Summary: Carvacrol and thymol are the primary constituents of oregano essential oil (OEO) and possess significant antibacterial, antiviral, and antifungal properties. Recent research has showcased the potent antioxidant, anti-inflammatory, antidiabetic, and cancer-inhibiting effects of OEO. The properties of OEO hold potential implications for the livestock and veterinary industries. This manuscript aims to evaluate the utility of OEO in the domains of animal husbandry and veterinary medicine. With a growing global concern over food safety and animal welfare issues, the livestock and veterinary industries are undergoing unprecedented changes. These changes have not only brought challenges within each industry, but also brought unprecedented opportunities for development. In this context, the search for natural and safe products that can effectively replace traditional veterinary drugs has become an important research direction in the fields of animal husbandry and veterinary medicine. Oregano essential oil (OEO), as a natural extract, is gradually emerging in the fields of animal husbandry and veterinary medicine with its unique antibacterial, antioxidant, and multiple other biological activities. OEO not only has a wide antibacterial spectrum, effectively fighting against a variety of pathogenic microorganisms, but also, because of its natural properties, helps us to avoid traditional veterinary drugs that may bring drug residues or cause drug resistance problems. This indicates OEO has great application potential in animal disease treatment, animal growth promotion, and animal welfare improvement. At present, the application of OEO in the fields of animal husbandry and veterinary medicine has achieved preliminary results. Studies have shown that adding OEO to animal feed can significantly improve the growth performance and health status of animals and reduce the occurrence of disease. At the same time, pharmacokinetic studies in animals show that the absorption, distribution, metabolism, and excretion processes of OEO in animals shows good bioavailability. In summary, oregano essential oil (OEO), as a substitute for natural veterinary drugs with broad application prospects, is gradually becoming a research hotspot in the field of animal husbandry and veterinary medicine. In the future, we look forward to further tapping the potential of OEO through more research and practice and making greater contributions to the sustainable development of the livestock and veterinary industries. [ABSTRACT FROM AUTHOR]

The aim of the study was to compare the extraction yields, chemical compositions and antimicrobial activities of essential oils obtained by hydrodistillation (HD) and volatile extracts obtained by supercritical fluid extraction extraction (SFE) from oregano (Origanum onites), lavender (Lavandula angustifolia), sage (Salvia officinalis), anise (Pimpinella anisum) and clove (Syzygium aromaticum). Essential oil compounds (EOCs) of the obtained materials from both techniques (HD and SFE) were determined by GC-MS/FID. Agar well diffusion method was used for the determination of antimicrobial activities on five different foodborne microorganisms (Staphylococcus aureus, Pseudomonas aeruginosa, Escherichia coli Enterococcus faecalis and Klebsiella pneumoniae). According to the results; extraction yields of SFE were found to be higher than HD for all tested aromatic plants. Active ingredient ratios (carvacrol, camphor, anethole, eugenole and linalol) varied depending on the extraction methods. SFE extracts were higher antimicrobial activity than HD essential oils, except clove extract on E. faecalis. [ABSTRACT FROM AUTHOR]

Given the demand for oregano oil in the food, pharmaceutical, and cosmetic industries, in this work for the first time an attempt was made to investigate innovative methods for extracting essential oil from oregano in order to reduce energy consumption and ensure high-quality product. Three different methods of distillation, conventional hydrodistillation (CH) and hydrodistillation with ultrasound application (UH) and with ultrasound pretreatment (UPH) were examined using a frequency of 20 kHz and an intensity ranging from 65 to 120 W. For each method, various parameters (amplitude level, pulse duration/pulse interval ratio, and treatment time) were examined for their effect on oil yield. The optimum distillation method and operating conditions were determined. The obtained oils were analyzed by gas chromatography–mass spectrometry (GC–MS) and characterized for their total phenolic content and antioxidant activity. In all treatments, the oil was collected at various time intervals and two mathematical approaches were selected for the kinetic modelling, namely, the first order kinetic model and the Peleg's model. Ultrasounds led to an increase in oil yield of 8% for UPH and 17% for UH, as compared to the conventional method, shorter distillation time, and slightly higher energy consumption that can be ignored taking into account the high price of the oil. The composition of oils distilled by ultrasounds was not differed from that of oil produced with the classic method. The use of ultrasounds increased the total phenolic content of the oils, whereas their antioxidant activity did not differ from that of the conventional product. [ABSTRACT FROM AUTHOR]

The present study aims to evaluate the antibacterial activity of five commercially available essential oils (EOs), Lavender (LEO), Clove (CEO), Oregano (OEO), Eucalyptus (EEO), and Peppermint (PEO), against the most-known MDR Gram-positive and Gram-negative bacteria—Staphylococcus aureus (ATCC 25923), Escherichia coli (ATCC 25922), and Pseudomonas aeruginosa (ATCC 27853)—alone and in various combinations. Gas Chromatography–Mass Spectrometry (GC-MS) analysis established their complex compositions. Then, their antibacterial activity—expressed as the inhibition zone diameter (IZD) value (mm)—was investigated in vitro by the diffusimetric antibiogram method, using sterile cellulose discs with Ø 6 mm impregnated with 10 µL of sample and sterile borosilicate glass cylinders loaded with 100 µL; the minimum inhibitory concentration (MIC) value (µg/mL) for each EO was calculated from the IZD values (mm) measured after 24 h. The following EO combinations were evaluated: OEO+CEO, CEO+EEO, CEO+PEO, LEO+EEO, and EEO+PEO. Then, the influence of each dual combination on the activity of three conventional antibacterial drugs—Neomycin (NEO), Tetracycline (TET), and Bacitracin (BAC)—was investigated. The most active EOs against S. aureus and E. coli were LEO and OEO (IZD = 40 mm). They were followed by CEO and EEO (IZD = 20–27 mm); PEO exhibited the lowest antibacterial activity (IZD = 15–20 mm). EEO alone showed the highest inhibitory activity on P. aeruginosa (IZD = 25–35 mm). It was followed by CEO, LEO, and EEO (IZD = 7–11 mm), while PEO proved no antibacterial action against it (IZD = 0 mm). Only one synergic action was recorded (OEO+CEO against P. aeruginosa); EEO+PEO revealed partial synergism against S. aureus and CEO+PEO showed additive behavior against E. coli. Two triple associations with TET showed partial synergism against E. coli, and the other two (with NEO and TET) evidenced the same behavior against S. aureus; all contained EEO+PEO or CEO+PEO. Most combinations reported indifference. However, numerous cases involved antagonism between the constituents included in the double and triple combinations, and the EOs with the strongest antibacterial activities belonged to the highest antagonistic combinations. A consistent statistical analysis supported our results, showing that the EOs with moderate antibacterial activities could generate combinations with higher inhibitory effects based on synergistic or additive interactions. [ABSTRACT FROM AUTHOR]

The present study evaluated the inclusion of fumaric acid and essential oil blends (EOBs) containing anise, cedarwood, clove, cumin, eucalyptus, garlic, ginger, lavender, lemongrass, nutmeg, oregano, and peppermint at different proportions on in vitro dry matter (DM) disappearance (DMD), fiber fraction disappearance, the efficiency of microbial production, and the total volatile fatty acids (VFAs). Ten treatments without (control treatment) or with different EOB/fumaric combinations were used in the study with eight replicates. The EOB inclusion level was 200 μL/g of feed (total mixed ration, (TMR)) while fumaric acid was administered at 3% of the TMR (DM basis). The highest DMD, in vitro true degradable DM, partitioning factor (PF24), and in vitro apparent degradable DM were recorded for the fumaric only treatment and the control. Neutral detergent fiber disappearance was reduced with the inclusion of EOB/fumaric combinations. The production of microbial mass and undegraded DM were higher (p < 0.001) for all EOBs and EOB and fumaric treatments. The inclusion of EOB and fumaric combinations reduced (p < 0.001) the total gas production, methane, and ammonia, with a higher PF24 value noted for EOB3 treatment. The inclusion of individual EOB1 containing garlic, lemongrass, cumin, lavender, and nutmeg in a ratio of 4:2:2:1:1 or combined with fumaric acid yielded the highest propionate concentration across all treatments. We concluded that EOBs decreased methane production and nutrient degradability with better results with the individual EOB1 or EOB1/fumaric combination, which showed a potential enhancement in energy production. [ABSTRACT FROM AUTHOR]

The generation of chemically engineered essential oils (CEEOs) prepared from bi-heteroatomic reactions using ammonium thiocyanate as a source of bioactive compounds is described. The impact of the reaction on the chemical composition of the mixtures was qualitatively demonstrated through GC–MS, utilizing univariate and multivariate analysis. The reaction transformed most of the components in the natural mixtures, thereby expanding the chemical diversity of the mixtures. Changes in inhibition properties between natural and CEEOs were demonstrated through acetylcholinesterase TLC autography, resulting in a threefold increase in the number of positive events due to the modification process. The chemically engineered Origanum vulgare L. essential oil was subjected to bioguided fractionation, leading to the discovery of four new active compounds with similar or higher potency than eserine against the enzyme. The results suggest that the directed chemical transformation of essential oils can be a valuable strategy for discovering new acetylcholinesterase (AChE) inhibitors. [ABSTRACT FROM AUTHOR]

Baccharis vulneraria Baker is used popularly for the treatment of skin infections. So, this study aimed investigate the antimicrobial activity and chemical characterization of the essential oil (EO) against microorganisms that cause cutaneous infections. The EO was analyzed by GC-MS. The antimicrobial test was performed using the serial microdilution method, and the antimicrobial activity was determined by the minimum inhibitory concentration against Staphylococcus aureus, Staphylococcus epidermidis, Escherichia coli, Pseudomonas aeruginosa, Candida albicans, Trichophyton interdigitale, Trichophyton rubrum, Fusarium solani and Fusarium oxysporum within the 32-0.0625 mg/mL concentration range. Were identified 31 EO compounds. Its major compounds are bicyclogermacrene, trans-cadin-1,4-diene, β-caryophyllene, and germacrene A. EO showed antifungal action against T. rubrum and T. interdigitale (2 and 4 mg/mL MIC, respectively). The growth of C. albicans, at 4 mg/mL, decreased by 50% compared to control. The oil had no significant potential for other microorganisms at the selected concentrations. [ABSTRACT FROM AUTHOR]

Simple Summary: Concerted efforts by scientists and researchers are still being made to ensure the medicinal plants will be available on a continuing basis as a result of their medicinal, pharmaceutical, food, and other uses and to meet the increasing demands for them globally. Satureja montana is one of the multi-use medicinal plants that was introduced to Egypt to study the effect of planting dates, nitrogen, phosphorus, and fertilizers, and their interaction on the production of fresh herb and essential oil. Planting in the autumn gave the highest fresh herb, with 55 kg of nitrogen/ha and 37 kg of phosphorus/ha fertilization. For the highest essential oil production, spring planting with 55 kg of nitrogen/ha and 74 kg of phosphorus/ha was used. Much of the knowledge on its use as raw material in traditional medicine has been reported. Also, this study's emphasis has been put on essential oil composition. This study highlights that the cultivated species belongs to S. montana L., a carvacrol chemotype. There is antioxidant, antimicrobial, and insecticidal activities shown by S. montana essential oil. Due to the limited information recorded about the influence of different agronomic factors on the plant, there needs to be agronomic studies conducted on S. montana, and a selection of the best ones in order to maximize its production. The rising demand for safe plant compounds and herbal products that contribute positively to human health is in line with current market trends. Plants belonging to the Satureja genus, particularly the aromatic medicinal S. montana L. from the Lamiaceae family, are well suited to these trends as they serve as pharmaceutical raw materials. This research aimed to assess the influence of sowing date and fertilization doses, as well as their interaction, on the fresh weight, essential oil content, and composition of S. montana. Experimental cultivation involved varying nitrogen and phosphorus levels. The second cut had the highest fresh weight and oil production compared to the first cut. The highest total plant biomass was achieved with autumn sowing and fertilization at 55 kg N/ha and 37 kg P/ha, whereas Spring sowing exhibited higher essential oil production, with the maximum oil % with 74 kg P/ha and oil yield after applying 55 kg N/ha and 74 kg P/ha. The GC-MS analysis revealed that carvacrol was the predominant compound, with it being recommended to grow S. montana in Spring at doses of 55 kg N/ha and 74 kg P/ha for the superior oil yield. Additionally, S. montana essential oil demonstrated notable biological and antimicrobial activity, positioning it as a potential alternative to chemical food preservatives. [ABSTRACT FROM AUTHOR]

Nectarines can be affected by many diseases, resulting in significant production losses. Natural products, such as essential oils (EOs), are promising alternatives to pesticides to control storage rots. This work aimed to test the efficacy of biofumigation with EOs in the control of nectarine postharvest diseases while also evaluating the effect on the quality parameters (firmness, total soluble solids, and titratable acidity) and on the fruit fungal microbiome. Basil, fennel, lemon, oregano, and thyme EOs were first tested in vitro at 0.1, 0.5, and 1.0% concentrations to evaluate their inhibition activity against Monilinia fructicola. Subsequently, an in vivo screening trial was performed by treating nectarines inoculated with M. fructicola, with the five EOs at 2.0% concentration by biofumigation, performed using slow-release diffusers placed inside the storage cabinets. Fennel, lemon, and basil EOs were the most effective after storage and were selected to be tested in efficacy trials using naturally infected nectarines. After 28 days of storage, all treatments showed a significant rot reduction compared to the untreated control. Additionally, no evident phytotoxic effects were observed on the treated fruits. EO vapors did not affect the overall quality of the fruits but showed a positive effect in reducing firmness loss. Metabarcoding analysis showed a significant impact of tissue, treatment, and sampling time on the fruit microbiome composition. Treatments were able to reduce the abundance of Monilinia spp., but basil EO favored a significant increase in Penicillium spp. Moreover, the abundance of other fungal genera was found to be modified. [ABSTRACT FROM AUTHOR]

Fusarium oxysporum f.sp. conglutinans (FOC) causes yellow wilt, a serious cabbage disease. This fungal species is composed of many strains within two pathotypes. In this study, the inhibitory effect of essential oils of six aromatic and medicinal plants (oregano, thyme, clove, cinnamon, lemongrass, litsea) at multiple concentrations on eight FOC isolates of different origins was investigated. Our results showed that oregano essential oil had the greatest inhibitory effect. The tested essential oils could be divided into three clusters according to the similar content of their main components (oregano and thyme, clove and cinnamon, lemongrass, and litsea), which correlated to some extent with their inhibitory effects on FOC. The tested isolates also differed in their response to the studied essential oils. The differences within FOC races were more important than between races, and the sensitivity of isolates against essential oils seemed to be more related to the geographical origin of the isolates, rather than to their race affiliation. [ABSTRACT FROM AUTHOR]

Simple Summary: Salmonella spp. of both human and animal origin have a high resistance percentage to tetracyclines. Essential oils, including cinnamon, clove, oregano, and red thyme, have demonstrated bactericidal activity against this bacterium. However, in many cases, the minimum inhibitory concentration (MIC) exceeds the cytotoxicity limits. The aim of this study was to evaluate the in vitro effectiveness of combining oxytetracycline with essential oils against multidrug-resistant Salmonella enterica strains. The results indicated a positive interaction (synergy and additivity) between oxytetracycline and the four oils that were tested. This led to a reduction in the MIC of both the oils and the antibiotic. The reduction was between 2 and 4 times the initial value for the oils and between 2 and 1024 times for the antibiotic. The best results were achieved with the combination of oxytetracycline and cinnamon, which decreased the effective concentration of this antibiotic to below the sensitivity threshold. Although differences in response were observed depending on the bacterial strain, there was no antagonistic effect in any case. The study suggests that combining oxytetracycline with cinnamon oil may be an effective alternative for controlling tetracycline-resistant strains of Salmonella, although further studies would be advisable. Tetracyclines have a high resistance percentage in Salmonella spp. of both human and animal origin. Essential oils, such as cinnamon (Cinnamomum zeylanicum), clove (Eugenia caryophyllata), oregano (Origanum vulgare), and red thyme (Thymus zygis), have shown bactericidal activity against this bacterium. However, in many cases, the minimum inhibitory concentration (MIC) exceeds the cytotoxicity limits. The objective of this study was to assess the in vitro efficacy of combining oxytetracycline with essential these oils against field multidrug-resistant (MDR) Salmonella enterica strains. The MIC of each product was determined using the broth microdilution method. The interaction was evaluated using the checkerboard method, by means of the fractional inhibitory concentration index (FICindex) determination. The results showed a positive interaction (synergy and additivity) between oxytetracycline and the four oils tested, resulting in a reduction in both products' MICs by 2 to 4 times their initial value, in the case of oils, and by 2 to 1024 times in the case of the antibiotic. The combination of oxytetracycline and cinnamon achieved the best results (FICindex 0.5), with a decrease in the antibiotic effective concentration to below the sensitivity threshold (MIC of the combined oxytetracycline 0.5 µg/mL). There was no antagonistic effect in any case, although differences in response were observed depending on the bacterial strain. The results of this study suggest that combining oxytetracycline with cinnamon oil could be an effective alternative for controlling tetracycline-resistant strains of Salmonella. However, its individual use should be further evaluated through in vitro susceptibility tests. [ABSTRACT FROM AUTHOR]

The citronellol-rich Origanum vulgare essential oil (OEO), which exhibits excellent antioxidant and antimicrobial activities, has limited use in food packaging owing to its high volatility and instability. This problem can be solved using electrospinning. In this study, OEO was incorporated into the zein matrix via emulsion electrospinning. OEO was obtained by hydro-distillation; gas chromatography–mass spectrometry analysis revealed that citronellol (44.34%) was a predominant compound in OEO. Scanning electron microscopy images demonstrated that the fibers had a bead-free and uniform structure with a diameter ranging from 215 ± 36 to 260 ± 72 nm. The X-ray diffractograms indicate the amorphous structure of the zein fibers. Fourier transform infrared absorption spectroscopy revealed an interaction between OEO and zein. The addition of OEO to the zein nanofibers affected its secondary structure. Thermogravimetric analysis showed that the OEO-loaded (OEO/zein) nanofibers exhibited high thermostability and that the water contact angle was enhanced. The encapsulation efficiency and loading capacity were in the range of 71.56–85.8% and 8.88–40.93%, respectively. The antioxidant activity of the OEO/zein nanofibers ranged from 45.40% to 71.50%. The OEO/zein fibers displayed antimicrobial activity against Staphylococcus aureus and Escherichia coli. In conclusion, OEO/zein nanofibers are promising alternatives for active food packaging. [ABSTRACT FROM AUTHOR]

Tomato is perishable and requires preservation to extend its shelf life. In this study, we conducted selection processes to identify essential oils that can help to avoid spoilage and deterioration during tomato storage and extend the shelf life. Thereafter, we determined the phosphatase activity assay, potassium ion concentration, and electron microscopy to study the antibacterial mechanism of essential oil. We found that Enterobacter ludwigii W01 was the dominant spoilage bacterium in tomatoes with cracked and curled skin. We selected oregano essential oil from 12 essential oils (oregano essential oil, lemon essential oil, osmanthus essential oil, cypress wood essential oil, tea tree essential oil, licorice essential oil, Baili essential oil, white camphor essential oil, Shancang seed essential oil, rosemary essential oil, rose essential oil, and cinnamon essential oil) which could significantly inhibit the activity of E. ludwigii W01. However, the diameter of the inhibition zone for Wh, Te, Cy, Li, Rm, Le, and Os is 0 mm, the diameter of the inhibition zone for Ba, Sh, and Ro was less than 1.0 mm, whereas the diameter of the inhibition zone for Ci and Or was greater than 2.0 mm. The diameter of the suppression circle for Ci and Or was greater than 2.0 mm, while Ci was lesser than Or. Oregano essential oil can damage the cell wall of E. ludwigii W01, leading to the leakage of the alkaline phosphatase stored between the cell wall and the cell membrane which can increase the alkaline phosphatase activity in the bacterial solution. Meanwhile, the addition of oregano essential oil significantly altered the cellular morphology of E. ludwigii W01. Spraying the surface of fresh tomato fruits with 1 MIC (0.125%) of oregano essential oil prolonged the storage time to 15 days, without significant changes in its sensory attributes. Those results indicated that oregano essential oil was a potential preservative for tomatoes. [ABSTRACT FROM AUTHOR]

In this study, the chemical composition of essential oils (EOs) extracted from Origanum vulgare ssp. hirtum Lamiaceae, (oregano), Salvia officinalis Lamiaceae (sage), Mentha pulegium Lamiaceae (pennyroyal), and respective hydrosols (HSs) has been investigated by Gas Chromatography–Mass Spectrometry (GC-MS). The antimicrobial activity was assessed against two oral pathogens: Gram-positive bacterium Streptococcus mutans and the fungus Candida albicans by determination of Minimum Inhibitory Concentration (MIC) and Minimum Bactericidal/Fungicidal concentration (MBC/MFC). Three-fold diluted solutions were dispensed into each well of a 96-well microtiter plate and, after incubation, MIC was determined by visual monitoring. The MBC/MFC was determined by transferring a small quantity of sample contained in each replicate well of the microtiter plates to appropriate culture media using a microplate replicator. The EOs of the tested herbs showed antimicrobial properties, especially the EO oil of O. vulgare, which exerted the highest antimicrobial activity. HSs of S. officinalis and M. pulegium exerted no antimicrobial activity, in contrast to oregano HS, which displayed strong antimicrobial activity. In all cases, a higher number of compounds were detected in EOs than in the corresponding HSs. The major compounds of sage EO were detected to be α-thujone (25.1%), 1,8-cineole (15.8%) and β-pinene (10.0%), while the HS was characterized by the presence of 1,8-cineole (32.6%), borneol (22.6%) and α-thujone (22.4%). Pennyroyal EO and HS consists mainly of pulegone (62.1 and 50.6%, respectively). Carvacrol was the major component present in EO (63%) and HS (97.3%) of oregano, probably contributing to the antimicrobial activity. Further research is needed in order to elucidate the antimicrobial mechanisms of specific compounds present in essential oils and hydrosols of Lamiaceae grown in Greece against oral pathogens. [ABSTRACT FROM AUTHOR]

We studied the effects of water-soluble (vitamin C, VC) and fat-soluble antioxidants (oregano essential oil, OEO) on the stress responses and redox status of Astyanax aff. bimaculatus exposed to air. Ten isoproteic and isoenergetic diets were formulated, with different levels of VC (0, 40, 80, 120, and 160 mg kg−1), with or without OEO (1,000 mg kg−1). Fish were fed these diets for 55 days, and then 18 fish from each group were exposed to air. VC at concentrations of 120 and 160 mg kg−1 reduced glycemia. In the gills, VC at 120 and 160 mg kg−1, only in combination with OEO, reduced oxidative damage (malondialdehyde, MDA, and carbonylated proteins, PC) and superoxide dismutase (SOD) activity. In the absence of VC, OEO increased PC and SOD. In the liver, all VC concentrations, without OEO, reduced MDA while in the presence of OEO, only VC at 40 and 160 mg kg−1 reduced MDA. Regardless of OEO, all VC concentrations reduced PC levels and SOD and catalase (CAT) activity. However, OEO increased CAT and glutathione S-transferase (GST) activity regardless of VC level. While VC at a concentration of 40 with 1,000 mg kg−1 OEO reduced oxidative damage to lipids in the gills and liver, a reduction in protein and lipid damage in the gills was only observed with a least VC 120 + OEO. Therefore, we recommend simultaneous supplementation of VC 120 + 1,000 OEO, as their combined use is more effective in reducing oxidative damage in A. aff. bimaculatus exposed to air. [ABSTRACT FROM AUTHOR]

Development of innovative botanical biopesticides is currently one of the most investigated areas, partly owing to their consideration as eco-friendly practice. Indeed, there are many different plants that have been proven to have pesticidal properties. One of these plants is Origanum vulgare L., that has been reported to have several bioactive activities including antibacterial, antifungal, insecticidal, antiviral, and antiacarian properties. This activity is due to the richness of essential oil and different extracts of this plant in volatile and non-volatile phenolic compounds. This review describes the activities of O. vulgare against some agricultural pests. This research was conducted using the following databases: Scopus, Springer, PubMed and ScienceDirect. In total 6346 articles were identified but just 83 from theme met the included criteria and were included in this review. For bacteria, nematodes, and mites, all of these experiments were completed in the laboratory, while no field research has been carried out. For insects, among the 33 studies, only one was carried out both in the laboratory and in the field. For fungi, 31% of studies have been executed under both in vitro and in vivo conditions. Most of the articles in this review (more than 90%) aimed to analyze the effect of O. vulgare essential oil. The pesticidal properties of this plant make it an effective candidate for pest control in agriculture. [ABSTRACT FROM AUTHOR]

Today, microbial contamination in food is one of the major problems of the food industry and public health in general around the world. Foodborne illnesses, such as diarrheal diseases, kill many people around the world each year. The general objective of this study was to evaluate the antioxidant and antibacterial activity of sodium alginate nanoemulsion coating incorporated with oregano essential oil (Origanum vulgare L.) and Trachyspermum ammi oil (Carum cupticum) on Escherichia coli, and Listeria monocytogenes. To achieve this study, fresh chicken meat was used for this experiment. Listeria monocytogenes ATCC 19111 and Escherichia coli ATCC 35218 were obtained from the American Type Culture Collection (Manassas, VA, USA). After the preparation of the essential oil, the chemical composition of this essential oil was determined by using (GC–MS). The physicochemical properties of the nanoemulsion essential oil prepared were characterized and their antimicrobial activity was evaluated. The results showed that the GC–MS analysis of the volatile constituents of the Origanum vulgare essential oil compounds allowed the identification of 19 compounds representing 93.72% of the total oil. The major components detected in Origanum vulgare essential oil were pulegone (49.25%), eucalyptol (18.23%), and menthone (12.37%). About the Carum cupticum essential oil, 21 compounds representing 98.5% of the total oil were identified. The major components detected in Origanum vulgare essential oil were thymol (23.3%), p‐cymene (17.5%), and γ‐terpinene (16.8%). The best z‐average (d.nm) is 483.4 nm (Carum cupticum essential oil + nano) followed by 470.1 nm (nanochitosan). The results of the antimicrobial test showed that the different preparations have a good inhibitory activity for the in vitro growth of Escherichia coli and Listeria monocytogenes. According to the MIC and MBC results of this study, the nanoemulsion also presented a good bacteriostatic activity against the two pathogenic bacteria tested in this study. [ABSTRACT FROM AUTHOR]

Fungal decay is one of the most significant causes of postharvest losses of blueberries, with Botrytis rot caused by Botrytis cinerea and Alternaria rot caused by Alternaria alternata being the two most destructive fungal diseases. Plant essential oil has attracted the extensive attention of scholars due to its natural antifungal and anti-corrosion effects. In this study, the effects of fumigation treatment with plant essential oils on the growth of pathogenic fungi in blueberry fruits in vitro and the activity of defense-related enzymes of fungi-inoculated blueberry were evaluated. The results showed that, of the six natural plant essential oils of cinnamon, oregano, clove, tea tree, pomelo peel, and rosemary, oregano essential oil had the most efficient inhibitory effect on Botrytis cinerea and Alternaria alternata in PDA. After fumigating inoculated blueberry fruits with concentration gradients of 0, 30, 60, and 90 μL/L of oregano essential oil, it was found that the activity of defense-related enzymes such as phenylalanine ammonia lyase (PAL), polyphenol oxidase (PPO), peroxidase (POD), chitinase (CHI), and β-1,3-glucanase (GLU) in the inoculated blueberry fruits was induced and enhanced to varying degrees throughout the entire storage period, effectively enhancing the resistance of blueberry fruits to pathogenic fungi and reducing the postharvest decay caused by Botrytis cinerea and Alternaria alternata. The optimal concentration for the fumigation treatment with oregano essential oil is 60 μL/L. This study provides a theoretical basis for the postharvest application of oregano essential oil in blueberries and other fruits and vegetables. [ABSTRACT FROM AUTHOR]

The antimicrobial effect of eight essential oils' vapors against pathogens and spoilage bacteria was assayed. Oreganum vulgare L. essential oil (OVO) showed a broad antibacterial effect, with Minimum Inhibitory Concentration (MIC) values ranging from 94 to 754 µg cm−3 air, depending on the bacterial species. Then, gaseous OVO was used for the treatment of stainless steel, polypropylene, and glass surfaces contaminated with four bacterial pathogens at 6–7 log cfu coupon−1. No viable cells were found after OVO treatment on all food-contact surfaces contaminated with all pathogens, with the exception of Sta. aureus DSM 799 on the glass surface. The antimicrobial activity of OVO after the addition of beef extract as a soiling agent reduced the Sta. aureus DSM 799 viable cell count by more than 5 log cfu coupon−1 on polypropylene and glass, while no viable cells were found in the case of stainless steel. HS-GC-MS analysis of the headspace of the boxes used for the antibacterial assay revealed 14 different volatile compounds with α-Pinene (62–63%), and p-Cymene (21%) as the main terpenes. In conclusion, gaseous OVO could be used for the microbial decontamination of food-contact surfaces, although its efficacy needs to be evaluated since it depends on several parameters such as target microorganisms, food-contact material, temperature, time of contact, and relative humidity. [ABSTRACT FROM AUTHOR]

Simple Summary: One of the main substances responsible for the unpleasant odor in boar meat is skatole, which is created by the breakdown of tryptophan by bacteria in the hindgut of pigs. This study aimed to assess the impact of three different plant extracts on skatole levels in the blood and adipose tissue of pigs, while elucidating their relationship with the hepatic skatole metabolism. Origanum vulgare essential oil and Schisandra chinensis extracts were chosen for their potential to mitigate intestinal skatole formation or enhance hepatic skatole degradation, thereby reducing its accumulation in adipose tissue. Garlic essential oil was investigated due to its established capacity to elevate skatole concentrations in adipose tissue. The findings revealed that garlic essential oil significantly influenced skatole accumulation by impeding hepatic degradation, whereas both oregano essential oil and Schisandra chinensis extracts had no discernible impact on skatole metabolism or its adipose tissue concentrations. One of the primary substances responsible for the unpleasant odor in boar meat is skatole. Enzymes belonging to the cytochrome P450 (CYP) family play a pivotal role in the hepatic clearance of skatole. This study aimed to investigate the impact of oregano essential oil (OEO), Schisandra chinensis extract (SC), and garlic essential oil (GEO) on hepatic CYP2E1 and CYP2A activity in pigs. In three consecutive trials, cannulated castrated male pigs were provided with a diet containing 0.2–0.3% of one of these plant extracts. Following a 14-day feeding period, the animals were slaughtered, and liver and fat samples were collected. The findings indicate that the activities of CYP2E1 were unaffected by any treatment. However, GEO treatment demonstrated a significant reduction in CYP2A activity (p < 0.05). Pigs treated with GEO also exhibited a notable increase in skatole concentrations in both plasma and adipose tissue. In contrast, animals fed SC displayed elevated skatole concentrations in plasma but not in fat tissue. OEO did not influence skatole concentrations in either blood or fat. Furthermore, the study revealed that a supplementation of 6 g GEO per animal per day induced a significant increase in skatole concentrations in blood plasma within 24 h. [ABSTRACT FROM AUTHOR]

Simple Summary: The health status and survival of calves are essential factors affecting the farm's production efficiency and economic efficiency; the main reasons threatening the health of calves are the slow development of the gastrointestinal tract and the low immunity of ruminants at a young age. The coordinated action of the host and its gastrointestinal microflora can improve these negative factors. To better enable the gastrointestinal microflora to play a positive role in the animal organism, the composition and abundance of microorganisms can be regulated in vitro by supplementation with exogenous substances. Oregano essential oil, a natural plant extract, has been reported to be a suitable growth promoter for livestock and poultry, which can promote growth and development, enhance gastrointestinal function, and improve immunity by regulating the gastrointestinal microbiota of ruminants. We investigated oregano essential oil as an exogenous supplement for regulating rumen microbiology in calves and found that it promotes VFA production and can influence calf growth performance and serum antibody levels. This experiment aimed to investigate whether supplementation of calves with different doses of oregano essential oil (OEO) could promote the development of the gastrointestinal tract and enhance the immune ability of calves by regulating the rumen microbiota. Twenty-four 70-day-old healthy and disease-free Holstein male calves were randomly divided into four groups, with the control group fed a basal diet, and the treatment group provided 4 g, 6 g, and 8 g of oregano essential oil per day in addition to the basal diet. After the 14-day pre-test, a 56-day formal test was conducted. At days 0 and 56 of the standard test period, calves were weighed, the average daily weight gain of calves during the test period was calculated, and serum samples were collected to measure the concentration of immunoglobulins (IgA, IgG, and IgM) in the serum; at day 56 of the formal test period, rumen fluid was collected from the calves, and 16SrRNA was sequenced to analyze changes in the rumen microbiota of the calves. The changes in the rumen microbiota of calves were analyzed by 16SrRNA sequencing. The results of the study showed that (1) OEO supplementation in calves significantly increased end weight and average daily gain (p < 0.05); (2) OEO supplementation in calves significantly increased serum concentrations of immunoglobulins IgA and IgM (p < 0.05); (3) OEO supplementation in calves significantly increased the abundance and diversity of rumen microbial organisms (p < 0.05); (4) OEO supplementation in calves significantly regulates the relative abundance of some species, and biomarkers with significant differences were screened by LEfSe analysis: g_Turicibacter, g_Romboutsia, f_Peptostreptococcaceae, f_Clostridiaceae, g_Clostridium_sensu_stricto_1, o_Clostridiales, g_unclassified_f_Synergistaceae, c_Coriobacteriia, o_Coriobacteriales, f_Atopobiaceae, g_Olsenella, p_Actinobacteriota, g_Defluviitaleaceae_UCG-011, f_Defluviitaleaceae, o_Corynebacteriales, g_Corynebacterium, f_Corynebacteriaceae, g_Shuttleworthia, f_Hungateiclostridiaceae, o_norank_c_Clostridia, g_Saccharofermentans, g_Streptococcus, f_Streptococcaceae, g_unclassified_o_Oscillospirales, and f_unclassified_o_Oscillospirales (p < 0.05, LDA ≥ 3); and (5) OEO supplementation in calves significantly enriched the metabolism of cofactors and vitamins pathway (p < 0.05). (6) Using Superman's correlation analysis, we screened unclassified_c_Clostridia, Shuttleworthia, and Christensenellaceae_R-7_group, three beneficial strains for calves. (7) Daily supplementation with 8g of OEO significantly affected rumen microbiota regulation in calves. [ABSTRACT FROM AUTHOR]

Tetranychus urticae, a prominent pest mite in strawberry and vegetable cultivation in China, has developed escalating resistance due to extensive chemical pesticide application. Consequently, there is an urgent need to identify safe and efficacious methods to reduce resistance development. In this study, 38 commercially available plant essential oils (EOs) were screened for their acaricidal potential and ability to inhibit oviposition. The findings revealed that 13 EOs exhibited notable acaricidal activity, with lemon EO demonstrating the highest toxicity, followed by sage, patchouli, frankincense, lemongrass, palmarosa, and oregano EOs. In addition, 18 EOs displayed significant inhibitory effects on oviposition, with lemon EO exhibiting the highest inhibition rate (99.15%) and inhibition index (0.98). Subsequently, sage, frankincense, clove, lemongrass, oregano, patchouli, myrrh, black pepper, palmarosa, and geranium EOs also showed inhibition rates exceeding 50%. Despite black pepper, clove, myrrh, and oregano EOs demonstrating relatively low toxicity against T. urticae, they exhibited heightened efficacy in inhibiting oviposition and suppressing population expansion. This study conducted a comparative assessment of the acaricidal and oviposition inhibition activities of EOs and their principal constituents, thus providing a theoretical basis for the development of botanical acaricides against T. urticae. [ABSTRACT FROM AUTHOR]

The antimicrobial activity of Origanum vulgare var. hirtum (O) and Coridothymus capitatus (C) essential oils (EOs) and hydrolates (HYs) of the same botanical species was evaluated on sixteen L. monocytogenes strains from food and clinical origins. The antimicrobial activity was assessed by Minimum Inhibitory Concentration (MIC) determination, viable cell enumeration over time up to 60 min, and evaluation of the cellular damage through Confocal Laser Scanning Microscope (CLSM) analysis. EOs exhibited antimicrobial activity with MIC values ranging from 0.3125 to 10 µL/mL. In contrast, HYs demonstrated antimicrobial effectiveness at higher concentrations (125–500 µL/mL). The effect of HYs was rapid after the contact with the cells, and the cell count reduction over 60 min of HY treatment was about 1.2–1.7 Log CFU/mL. L. monocytogenes cells were stressed by HY treatment, and red cell aggregates were revealed through CLSM observation. Moreover, the combinations of EOs and HYs had an additive antilisterial effect in most cases and allowed the concentration of use to be reduced, while maintaining or improving the antimicrobial effectiveness. The combined use of EOs and HYs can offer novel opportunities for applications, thereby enhancing the antimicrobial effectiveness and diminishing the concentration of use. This provides the added benefit of reducing toxicity and mitigating any undesirable sensory effects. [ABSTRACT FROM AUTHOR]

Simple Summary: It is a big challenge to maintain a healthy state in sows during late gestation and lactation, and it directly impacts the performance of both sows and their offspring. Essential oil, consisting of multiple active compounds, is regarded as a promising feed additive. In this study, maternal diets were supplemented with oregano essential oil during late gestation and lactation to investigate its potential effects. We collected and analyzed serum and fecal samples from sows to evaluate performance, serum metabolites, antioxidant capacity and fecal microbiota, aiming to provide valuable insights into the utilization of oregano essential oil in animal production. A total of 20 healthy white × landrace sows were evenly and randomly divided into two groups, and fed basal diets unsupplemented or supplemented with 500 g/t Meriden-Stim® from day 100 of gestation until day 21 of lactation. Serum and fecal samples were collected from the sows on the final day for subsequent analysis. Compared to the control group, there were no significant differences in the sows' performances; however, an increase was observed in the piglets' weight at weaning (p = 0.08). Moreover, oregano essential oil (OEO) significantly reduced the levels of urea (UREA) (p < 0.01), total cholesterol (TC) (p < 0.05), low-density lipoprotein (LDL-C) (p < 0.05) and alanine aminotransferase (ALT) (p < 0.05) in serum. In terms of antioxidant indexes in serum, the catalase (CAT) and glutathione (GSH) levels showed significant increases (p < 0.05) while the malondialdehyde (MDA) level exhibited a decrease tendency (p = 0.09). 16S rRNA analysis identified the specific bacteria taxa in feces. OEO significantly decreased the relative abundance of Proteobacteria and Actinobacteria at the phylum level (p < 0.05). At the genus level, OEO significantly increased the relative abundance of Lactobacillus and Prevotellaceae UCG 003 and UCG 005, while decreasing that of Escherichia-Shigella (p < 0.05). Taken together, OEO supplementation in maternal diets during late gestation and lactation improved serum metabolites, antioxidant capacity and regulated the intestinal-flora balance of sows, thereby tending to increase the piglets' weight at weaning. [ABSTRACT FROM AUTHOR]

Background and Aim: The objective was to evaluate the effect of a cream based on the essential oil of Origanum vulgare on skin lesions induced in Mus musculus Balb/c. Materials and Methods: The experimental animals were divided into four groups of 6 specimens each, in which skin lesions of approximately 1 cm in diameter were induced. Group I (Control) received no treatment, Group II (0.1% Origanum vulgare cream), Group III (0.5% Origanum vulgare cream), and Group IV (1% Origanum vulgare cream) received treatment for eight days. Skin lesions were measured on days 4 and 7. At the end of treatment, they were euthanized using sodium pentobarbital 60 m/kg v.ip. Skin samples were obtained and preserved in 10% formalin for histopathological analysis. Results: When measuring the size of the skin lesions induced in the study groups, it was observed that in the control group, the decrease in the length of the lesions occurred on the fifth day; in group II, III, and IV, the lesions length decrease occurs on the second day. At the end of the experience, the measurements of the lesions were much smaller for the III and IV groups (0.33 and 0.41, respectively) compared to the control group (0.40 cm). On day seven, statistically significant difference was found on skin lesion measure between Group IV and the Control, with a significance level of p<0.05. Conclusion: It is concluded that the 1% Origanum vulgare essential oil-based cream has a healing effect on dermal lesions induced in Mus musculus Balb/c. [ABSTRACT FROM AUTHOR]

The aim of this study was to investigate the suitability of selected essential oils as more environmentally friendly, sustainable antimicrobial agents in photographic films for long‐term data storage. For this purpose, essential oils of oregano, thyme, and lemongrass were added in concentrations ranging from 0.4% to 4% to the gelatin comprising a protective layer for photographic microfilms. The emulsions were analyzed via UV‐Vis for their optical transparency, then tested for their antimicrobial efficacy against Bacillus subtilis, Staphylococcus hominis and Staphylococcus epidermidis. Thin coatings generated by spreading and drying the emulsions onto photographic film substrates were then characterized morphologically via SEM before and after standardized artificial aging procedures. It was found that oregano oil at a concentration of 0.4% maintained the optical and physical properties of the emulsion and proved highly effective against all tested bacteria. Thyme and lemongrass oil also exhibited some antimicrobial activity, however, were not able to inhibit the bacterial growth completely. At higher concentrations of the oils, the gelatin coatings cracked after artificial aging, which makes them unsuitable for the application. To conclude, selected essential oils like oregano oil can be used as an effective antimicrobial agent without compromising the quality of the photographic films. Practical Applications: The results of our research can be applied directly to the manufacturing of photographic films, specifically ones intended for long‐term data storage. Furthermore, many applications of gelatin or related materials which require antimicrobial activity, such as food packaging, could be enhanced by the addition of essential oils. [ABSTRACT FROM AUTHOR]

Flora of Türkiye is hosting many Origanum sp. and spp. valuable members of Lamiaceae, including outstanding endemic species and hybrids. Those are having a number of using field and still meeting the World's major demand. Five combinations of artificial Oregano hybrids were cultivated in Ankara ecological conditions. Among those species; Origanum minutiflorum and Origanum onites are endemic to the flora of Türkiye and the combinations of those hybrids are very valuable and unique. According to the field studies results; the highest green herb yield was provided from H4 as 439.93g and from H5 as 317.26 g x plant-1. H2 and H3 showed the highest green leaf yield by 278.69 and 244.33 g x plant-1, and the highest leaf ratio (%). The essential oils ranged between 4.20% and 5.96%, Carvacrol predominated in the hybrids at; 77.90% (H1), 61.26% (H3) and 26.99% (H4), 72.09 (H5), and linalool at 45.86% (H2). [ABSTRACT FROM AUTHOR]

High rates of resistance to antibiotics are associated with healthcare-related infections, thus demonstrating the urgent need for effective antimicrobials against these maladies. The present study aims to determine the chemical composition of essential oil (EO) from Clausena anisata leaves and evaluate their antibacterial activity against selected nosocomial bacteria. To this end, one kilogram (1 kg) of fresh leaves of C. anisata was washed and boiled with 500 mL of distilled water for 2−4 h using a Clevenger apparatus. The oil was then collected in an Erlenmeyer, dried using anhydrous sodium sulfate, bottled in a tinted glass bottle and refrigerated at 4 °C before analysis. Next, the as-prepared oil was analyzed using gas chromatography-mass spectrometry (GC-MS). The essential oil was further tested against a panel of selected nosocomial bacteria, including Staphylococcus and Klebsiella species, among others, by microdilution using a resazurin assay to determine the minimum inhibitory and minimum bactericidal concentrations (MICs and MBCs, respectively). As a result, 0.77% of EO was extracted from fresh leaves of C. anisata. The GC-MS analysis revealed that the as-prepared essential oil contained E-anethole (70.77%), methyl isoeugenol (13.85%), estragole (4.10%), γ-terpinene (3.33%), myrcene (2.82%) and sabinene (0.77%), with E-anethole being the major constituent. Twenty-two compounds were identified in the EO of C. anisata leaves through gas chromatography. Upon antibacterial testing against selected nosocomial pathogens, the E-anethole-rich essential oil exhibited MIC and MBC values ranging from 3.91 to 125 µg/mL and 7.81 to 125 µg/mL, respectively, indicative of a bactericidal orientation of the plant's essential oil (MIC/MBC ratio < 4). This novel contribution highlights the scientific validation of the use of C. anisata leaves in the traditional treatment of various infectious diseases. However, toxicity and pharmacokinetic studies, mechanistic bases of the antibacterial action, and in vivo antibacterial experiments of the E-anethole-rich EO of C. anisata should be investigated to successfully use this plant in the treatment of infectious diseases. [ABSTRACT FROM AUTHOR]

Yersiniosis, one of the leading foodborne infections in the European Union, is caused by Yersinia enterocolitica. In this study, the antibacterial and antibiofilm effects of cinnamon (Cinnamomum zeylanicum Nees), clove (Syzygium aromaticum L.), oregano (Origanum vulgare L.), rosemary (Rosmarinus officinalis L.), thyme (Thymus vulgaris L.), and winter savory (Satureja montana L.) essential oils were investigated against Y. enterocolitica strains belonging to the bioserotype 4/O:3. Cinnamon essential oil showed the highest antibacterial activity, with an MIC value 0.09 µL/mL, followed by oregano and thyme essential oils, with MIC values from 0.09 to 0.18 µL/mL, and from 0.18 to 0.23 µL/mL, respectively. Thyme essential oil at 0.23 µL/g (MIC) and at 0.46 µL/g (2MIC) significantly (p < 0.05) reduced the number of Y. enterocolitica by 0.38 log CFU/g and 0.64 log CFU/g, respectively, in minced pork meat during storage at 4 °C for 4 days. The Y. enterocolitica strains formed biofilms at 15 °C and 37 °C in tryptic soy broth and Luria–Bertani broth, while no biofilms were obtained at 5 °C, and in meat broth nutrient media. Applying the minimum bactericidal concentrations of cinnamon, clove, oregano, rosemary, thyme, and winter savory essential oils on preformed biofilms led to significant reductions being observed in the range from 45.34% to 78.89%. A scanning electron microscopy assay showed the devastating impact of oregano and thyme essential oils on the morphology of Y. enterocolitica bacterial cells. In conclusion, the results of this study show that essential oils possess high anti-Yersinia and antibiofilm effects. [ABSTRACT FROM AUTHOR]

Sheep's second cheese whey (SCW), the by-product resulting from whey cheese production, was used as a component of cheese coatings containing oregano (Origanum compactum) and clary sage (Salvia sclarea) essential oils (EOs). SCW powder was obtained by the ultrafiltration/diafiltration of SCW followed by reverse osmosis and freeze drying. The coatings were produced with a mixture of SCW and whey protein isolate (WPI) using glycerol as plasticizer. Model cheeses were produced with cow´s milk and those containing SCW:WPI coatings; those with and without EOs were compared to controls without coating and with a commercial coating containing natamycin. At the end of ripening (28 days), the cheeses containing EOs presented higher water activity (ca. 0.930) and moisture content, as well as lower titratable acidity. Concerning color parameters, significant differences were also observed between products and as a result of ripening time. However, the use of SCW:WPI coatings did not significantly influence the color parameters at the end of ripening. Regarding texture parameters, the cheeses containing SCW:WPI coatings presented significantly lower values for hardness, chewiness, and gumminess. Significant differences were also observed for all microbial groups evaluated either between products and as a result of ripening time. In all cases, lactobacilli and lactococci counts surpassed log 7–8 CFU/g, while the counts of yeasts and molds increased steadily from ca. log 3 to log 6 CFU/g. The lowest counts of yeasts and molds were observed in the samples containing natamycin, but nonsignificant differences between products were observed. In conclusion, SCW:WPI cheese coatings can successfully substitute commercial coatings with the advantage of being edible packaging materials manufactured with by-products. [ABSTRACT FROM AUTHOR]