Search Results (291)

Lavender essential oil is a promising bioactive ingredient, but its incorporation into aqueous formulations is limited by its low water solubility and high volatility. This work structured lavender oil-in-water emulsified systems through two approaches: Ghassoul clay incorporation and increased oil loading. The standard formulation containing 1.25 wt.% oil showed a narrow droplet size distribution, with a Sauter mean diameter of 114 nm, respectively, and Newtonian behavior with a viscosity of 0.97 mPa·s. Ghassoul addition did not significantly modify droplet size, but induced shear-thinning and gel-like behavior. Zero-shear viscosity increased from 2 Pa·s at 5 wt.% clay to 550 Pa·s at 20 wt.%, while 15–20 wt.% Ghassoul showed the highest resistance to clay sedimentation after 30 days. Increasing lavender oil concentration promoted droplet growth and broader size distributions. The 30 wt.% oil formulation exhibited the strongest droplet-mediated structure, with G′ exceeding G″ and zero-shear viscosity reaching 156 Pa·s, whereas 40 wt.% oil weakened the network due to droplet coarsening and polydispersity. The results highlight the key role of clay-particle networking, droplet crowding, droplet-size distribution, and viscoelastic structuring in controlling gel-like behavior and physical stability, supporting the design of essential oil-based colloidal gels for topical, pharmaceutical, or cosmetic delivery applications. Full article

Lavender essential oil (LEO) possesses broad therapeutic potential, yet translating empirical knowledge into evidence-based medicine is hindered by the descriptive literature that conflates isolated monoterpene mechanisms with whole-oil efficacy. Addressing these critical shortcomings, this review presents a target-centric synthesis that explicitly delineates the molecular pathways of pure constituents (e.g., linalool, linalyl acetate) versus intact LEO matrices and standardized oral preparations (Silexan™). We systematically integrate LEO’s multi-target signaling networks across neuroregulatory, analgesic, anti-inflammatory, and skin-regenerative domains, while critically examining how genetic taxonomy, environmental stress, and green extraction technologies dictate chemotype diversity. Furthermore, we candidly address current evidence limitations, including pre-clinical predominance, publication bias, and clinical trial narrowness. Finally, we outline actionable translational strategies centered on chemotype-driven standardization, smart delivery systems, and a dual pharmacological paradigm that valorizes non-volatile processing byproducts. This synthesis establishes a rigorous theoretical foundation for LEO’s clinical translation and pharmaceutical standardization. Full article

Essential oils are widely recognised for their bioactive properties and therapeutic effects. Despite their potential, their practical application is often limited by intrinsic physicochemical constraints, including volatility, chemical instability, hydrophobicity and, most of all, compositional complexity. The development of effective delivery systems is therefore key to stabilise essential oil constituents, improve bioavailability and enable controlled release. Here we provide a comprehensive analysis of formulation strategies for essential oils, focusing on emulsification and encapsulation techniques. Emulsion-based delivery systems, including nanoemulsions and microemulsions, are discussed in relation to their interfacial behaviour, surfactant interactions and preparation methods. In parallel, encapsulation systems, such as vesicular systems, lipid-based carriers, polymeric nanoparticles and inclusion complexes, are evaluated according to their structural characteristics, protective capabilities, encapsulation efficiencies and release profiles. Collectively, these approaches are examined in the context of their influence on the stability, functionality, and overall performance of essential oil formulations. Emphasis is placed on essential oil-specific challenges that arise when preparing a formulation, especially the heterogenous nature of their chemical composition and its impact on physicochemical properties, partitioning, loading capacity, stability and safety. To contextualise these principles, representative examples of essential oil-based formulations (e.g., thyme, clove, rosemary and mint), formulated singular metabolites (e.g., carvacrol, eucalyptol, limonene and eugenol) and essential oil patent applications (>20,000) and products are outlined to illustrate behaviour and performance within the respective delivery system. Overall, the fundamental design considerations that guide the rational selection, preparation and evaluation of formulations for essential oil-based applications are discussed. Considerations for future directions are also outlined. Full article

Mediterranean aromatic plants are valuable sources of essential oils (EOs) with biological properties that hold promise for sustainable weed management. This study evaluated the phytotoxic activity of EOs from Thymus vulgaris L., Lavandula angustifolia Mill., and Salvia officinalis L. in vitro against key weed species common to Mediterranean agroecosystems. The EOs were tested at concentrations ranging from 0.125 to 1.50 µL mL⁻¹, assessing their impact on seed germination and early seedling growth of Avena fatua L., Lolium rigidum Gaudin, Sonchus oleraceus L., and Amaranthus retroflexus L. Thyme EO, primarily composed of thymol and γ-terpinene, exhibited the strongest phytotoxic activity, completely inhibiting the germination of A. fatua, L. rigidum, and S. oleraceus at all concentrations tested. In contrast, A. retroflexus was the most resistant weed species, with germination fully inhibited only at concentrations ≥ 0.50 µL mL⁻¹. Lavender EO, rich in linalool and linalyl anthranilate, demonstrated a more species-specific effect. It almost entirely suppressed the germination of S. oleraceus at all doses and inhibited germination of A. fatua and L. rigidum at concentrations ≥ 0.50 µL mL⁻¹. Again, A. retroflexus was the most tolerant species, with complete inhibition occurring only at the highest concentrations applied. Sage EO, containing eucalyptol and thujone as its main constituents, was the least effective, fully inhibiting S. oleraceus germination at concentrations ≥ 1.00 µL mL⁻¹, and L. rigidum at 1.50 µL mL⁻¹. Seedling growth was highly sensitive to EO treatments, even when germination was not entirely suppressed. These results highlight the potential of Mediterranean Lamiaceae EOs as plant-derived bioherbicides for integrated weed management. Full article

Background: Multidrug-resistant and biofilm-forming staphylococci pose a threat to the sustainability of public health, livestock health and the ecosystem. Pathogenic potential with a worsening prognosis of therapy is mainly due to methicillin-resistant Staphylococcus aureus (MRSA) or multidrug-resistant Non-aureus staphylococci and mammaliicocci (NASM). Alternative approaches based on the use of biosynthesized nanoparticles or substances of natural origin appear to be promising solutions to the problem of ineffective suppression of infections caused by pathogenic microorganisms. Methods: The aim of this study was to monitor and compare the biological effects of silver nanoparticles prepared by green synthesis using Lavandula angustifolia and lavender essential oil. In particular, the antibacterial, antibiofilm, and biofilm-eradicating effects against biofilm-forming and multidrug-resistant reference strains and field isolates of staphylococci were monitored. Results: AgNPs inhibited the growth and formation of biofilms of S. aureus strains at a concentration of 0.05 μg/μL, but clinical NASM at 0.025 μg/μL. Sensitivity to Lavender essential oil (LEO) was the same against all tested staphylococcal strains, with an antibacterial MIC of 0.901 μg/μL. The essential oil also had an effect on biofilm formation against all tested strains, but its effect was recorded at a tenfold lower concentration (antibiofilm MIC = 0.0901 μg/μL). No eradication activity was recorded for either tested substance. Their activity against the formed biofilms was not recorded. Conclusions: The results demonstrate promising antibacterial and antibiofilm activities of biosynthesized AgNPs and lavender essential oil under in vitro conditions. These findings support further investigation of these materials as potential alternative antimicrobial approaches, particularly in combination with conventional antimicrobial agents. Full article

This study investigated the influence of filamentary cold plasma (FCP) pretreatment on the isolation kinetics, yield and quality of lavender essential oil obtained by hydrodistillation (HD) and steam distillation (SD) at pilot scale. Lavender flowers were processed with or without FCP treatment under identical HD and SD conditions. FCP promoted tissue electroporation and the formation of additional mass transfer pathways in the calyx, shortening isolation time and increasing essential-oil yield from 2.46% to 2.65% for HD and from 2.33% to 2.65% for SD. In the SD process, FCP reduced process time from 240 ± 5.8 min to 95.3 ± 6.1 min to obtain an equal oil yield volume and decreased the specific energy consumption from 0.35 to 0.14 kWh mL⁻¹ of essential oil. GC–MS analysis confirmed that FCP did not deteriorate the volatile profile; linalool and linalyl acetate were the dominant constituents, with the relative contribution of other compounds depending on the distillation method. The combined linalool and linalyl acetate fraction increased from 65.9% to 68.2% after HD and from 63.49% to 68.11% after SD, indicating partial conversion of bound essential oil into a more extractable form. These results demonstrate that conveyor-based FCP pretreatment can intensify lavender oil production while preserving oil quality and provide practical parameters for assessing industrial-scale implementation. Full article

Background: The present study aimed to develop and characterize three honey- and essential oil-based structured systems intended for topical skin application. Materials and Methods: The semisolid systems were prepared as oil-in-water structured emulsions containing four types of honey (Manuka, Tualang, chestnut, and manna), three essential oils (palmarosa, cistus, and lavender), and five vegetable oils (pomegranate seed, aloe, centella, hemp seed, and calendula). Each formulation consisted of two honey types, one essential oil, and two vegetable oils, with final concentrations of 5% honey and 0.1–0.2% essential oil. The formulations were investigated through physicochemical, rheological, and in vivo skin evaluations. Results: Rheological analysis demonstrated non-Newtonian pseudoplastic behavior with shear-thinning and thixotropic characteristics, indicating that the systems are structured, semisolid, and suitable for topical application. Differences in spreadability and consistency suggested variations in the internal organization of the emulsion matrices. In vivo skin assessments were performed over four weeks using non-invasive instrumental methods. The obtained results demonstrated improvements in skin hydration, elasticity, firmness, and skin barrier function, together with reductions in transepidermal water loss and erythema. The evaluation of skin textural parameters revealed improvements in skin uniformity and a reduction in the appearance of wrinkles. Among the tested structured systems, F3 formulation exhibited the most pronounced moisturizing effect, while F1 formulation showed notable improvements in parameters associated with skin texture and wrinkle-related features. Conclusions: Overall, the results indicate that honey-based topical systems enriched with essential and vegetable oils represent promising multifunctional semisolid formulations for topical skin-conditioning and barrier-supportive applications. Their favorable rheological behavior, combined with beneficial effects on skin hydration, barrier function, and skin surface properties, supports their potential use in skin-conditioning and anti-aging-related formulations. Full article

The study aimed to characterize Romanian lavender essential oils (LEOs) according to geographical regions and harvested years by combining gas chromatography–mass spectrometry (GC/MS) with chemometric analysis and quality evaluation. Sixty-four LEO samples were collected from three Romanian areas (Moldova, Transylvania, Muntenia) during three consecutive years (2023–2025). GC–MS profiling identified 45 volatile compounds, with linalool, linalyl acetate, 1,8-cineole as predominant constituents. Oil quality was assessed using both a quality scoring algorithm based on characteristic volatile compounds and compliance with the ISO 3515:2002 standard. Most samples were classified as very good quality according to the proposed quality score, whereas only three samples fully complied with all ISO requirements. Pearson correlation analysis revealed significant positive associations among several biosynthetically related compounds, indicating identical variation within the volatile fingerprint. Linear discriminant analysis (LDA) successfully discriminated samples according to both geographical origin and harvest year, identifying characteristic combinations of volatile compounds responsible for sample classification. The results demonstrate that the overall volatile fingerprint, rather than individual compounds, provides a reliable basis for the authentication and differentiation of Romanian lavender essential oils. The combined GC–MS and chemometric approach represents an effective tool for quality evaluation, geographical traceability and authenticity assessment of lavender essential oils. Full article

The growing demand for natural and sustainable preservatives has renewed interest in essential oils (EOs) because of their potential antimicrobial and antioxidant activities. In this study, lemon, lavender, and oregano EOs, together with tomato and artichoke extracts, were evaluated against foodborne and spoilage microorganisms using an impedometric approach. Three bacterial strains (Listeria innocua, Escherichia coli, and Pseudomonas fluorescens) and two yeast strains (Zygosaccharomyces bailii and Kluyveromyces marxianus) were tested. Tomato and artichoke extracts showed no antimicrobial activity under the tested conditions, with MIC values higher than 66.67 µL/mL. Among the EOs, oregano EO showed the strongest antimicrobial properties, with both bacteriostatic and bactericidal effects, even at low concentrations for all tested strains. In contrast, lavender EO was the most effective against yeast, with MIC and MFC values of 0.75 µL/mL for both species. Antioxidant activity, assessed via DPPH and Oxitest assays, was highest for oregano EO, which showed a 95% total antioxidant capacity and an induction period of 1224 min. Overall, the results support the use of impedance-based methods as a rapid and informative tool for screening natural preservatives and identify oregano EO as the most promising multifunctional candidate, combining strong antibacterial and antioxidant properties. Full article

The proliferation of methicillin-resistant Staphylococcus aureus (MRSA) in food processing is an escalating public health issue. This circumstance has intensified the quest for ecological alternatives to impede pathogen proliferation and avert food degradation. This study firstly investigated the chemical compositions of three essential oils (EOs) sourced from Eucalyptus, Rosemary and Lavender plants using GC-MS. Subsequently, the antibacterial and antibiofilm activities of the tested EOs were assessed against MRSA strains. The effects of these EOs on the expression of antibiotic resistance-related (mecA), virulence regulatory (agrA and sarA), and enterotoxin (sea) genes in MRSA strains were also evaluated by real-time PCR. Concerning the composition analyses performed on the EOs, our results revealed a total of 82 compounds, which accounted for 99.20, 98.10 and 92.78% of Eucalyptus, Rosemary and Lavender EOs, respectively. The anti-staphylococcal activity showed that Eucalyptus EO had the greatest effect, with diameter of inhibition exceeding 41 mm. Moreover, the association between Rosemary EO and the antibiotic (cefoxitin) highlighted the enhancement of the antibacterial effect against the MRSA reference strain. Additionally, Eucalyptus EO showed the highest inhibitory effect against both strains, with MIC values ranging from 0.781 to 1.563 mg/mL, followed by the Rosemary and Lavender EOs. All the tested EOs displayed a bactericidal effect against the tested MRSA strains. Regarding the antibiofilm activity, Rosemary and Lavender EOs had varying impacts on the pre-formed biofilms, with percentage reduction values ranging from 36% to 73% and 37% to 68%, respectively. Finally, the mRNA expression of the MRSA gene A mecA and virulence genes agrA, sarA and sea declined following EO treatment compared with the control. The findings of this study highlighted the efficacy of locally tested EOs in reducing MRSA biofilm formation and the expression of virulence factors and suggested their potential use in food safety and culinary applications. Full article

This study investigated the effects of environmental conditions on polycyclic aromatic hydrocarbon (PAH) emissions from scented candles during combustion. An exposure chamber was established and validated to ensure stability and uniformity before the experiments were conducted. One of the most widely used scented candles (paraffin wax + 6% lavender essential oil) was selected in the present study. Testing environmental conditions included three relative humidity (RH) levels (60%, 75%, and 90%) and three air exchange rates (ACHs) (0.5, 1.0, and 2.0 h⁻¹). For each tested environmental condition, three replicate measurements were conducted. Gas-phase and particle-bound polycyclic aromatic hydrocarbons (PAHs) were collected using filter cassettes and XAD-2 sorbent tubes, respectively. Results showed that, under identical RH conditions, both C_total-PAHs and EF_total-PAHs followed the trend of 0.5 ACH > 2.0 ACH > 1.0 ACH, whereas total-Bap_eq and EF_Total-BaPeq values decreased with increasing ACH. While under identical ACH conditions, emissions showed a nonlinear response to RH, following the trend: 75% > 90% > 60%. Most detected PAHs were present in the gaseous phase and were dominated by low-molecular-weight compounds containing two to three aromatic rings. The estimated highest incremental lifetime lung cancer risk reached 1.20 × 10⁻⁶ for aromatherapy workers, assuming an exposure duration of 8 h day⁻¹ over 40 years. These findings highlight the potential health risks associated with the use of scented candles and emphasize the importance of adequate ventilation to reduce long-term indoor exposure. Full article

Steam distillation residues (SDRs) of aromatic plants were utilized to produce antioxidant extracts using hydroalcoholic solvents with increasing percentages of ethanol (0, 50, 75 and 100% v/v). The phenolic composition and antioxidant power were measured and compared to the corresponding fresh aromatic plants (FAPs). The largest amount of polyphenols, ranging from 14.15 (lemon balm FAP) and 19.61 (lavender SDR) mg gallic acid equivalents/g dry matter (DM), was found in 0% ethanol (pure water) extracts. The phenolic content of lavender and spearmint SDR extracts was higher than that of the corresponding FAP extracts, while the opposite was observed with lemon balm. Rosmarinic acid was the most abundant hydroxycinnamic acid detected, ranging from 608.65 µg/g DM in lemon balm 50% ethanol FAP extract to 697.47 µg/g DM in spearmint 50% ethanol SDR extract. The lavender and spearmint SDR extracts exhibited higher antioxidant power than the FAP extracts, while the extracts from fresh lemon balm were more antioxidant than the SDR. The lavender 50% ethanol SDR extract showed the highest scavenging activity (67.16%) and ferric reducing power (16.60 mg ascorbic acid equivalents/g DM). These results prove that spent aromatic residues can be utilized to produce antioxidant blends for various industrial applications. Full article

Background/Objectives: Lavandula cariensis species is cultivated uncommonly in the western region of Turkey. The colloquial appellations avayianos, karabasi, and myra are used to refer to the L. cariensis plant. The essential oil of L. cariensis was studied for its potential antiglaucoma, antioxidant, antidiabetic, and acetylcholinesterase inhibitory effects. Methods: The inhibitory effect of the essential oil of L. cariensis on the acetylcholinesterase (AChE), carbonic anhydrase II (CA II), and α-amylase enzymes was determined. Therefore, chemical profiles of L. cariensis’ essential oil were identified using Gas Chromatography Mass Spectrometry (GC-MS) and as Chromatography with Flame Ionization Detection (GC-FID) analyses. Results: Camphor (39.73%), fenchone (19.49%), exobornyl acetate (6.81%), camphene (5.49%), and eucalyptol (5.49%) were the most abundant compounds in L. cariensis essential oil. Radical scavenging effect of the essential oil of L. cariensis was examined using 1,1-diphenyl-2-picrylhydrazyl (DPPH) (IC₅₀: 231.0 ± 0.094 μg/mL) and 2,2′-azino-bis(3-ethylbenzthiazoline-6-sulfonic acid) (ABTS) (IC₅₀: 7.45 ± 0.013 μg/mL) radicals. Also, the ferric ions (Fe³⁺), cupric ions (Cu²⁺), and Fe³⁺-2,4,6-tri(2-pyridyl)-S-triazine (TPTZ) complex reducing capabilities were studied. Additionally, essential oil of L. cariensis indicated a comparable level of inhibition towards hCA II (IC₅₀: 276.42 μg/mL), AChE (IC₅₀: 14.22 μg/mL), and α-amylase (IC₅₀: 475.63 μg/mL) enzymes. Conclusions: The evaluation of the antioxidant capabilities and enzyme inhibition profiling of the essential oil of L. cariensis will be made possible by this comprehensive study, which serves as a springboard for further research. The essential oil of L. cariensis demonstrated enzyme-inhibitory activities against target enzymes associated with Alzheimer’s disease, diabetes, and glaucoma. Also, this study’s in vitro inhibition suggests promising prospects. Full article

Excessive application of chemical preservatives has raised increasing concerns regarding food safety and human health, prompting the search for safer natural alternatives. Lavender essential oil (LEO), a plant-derived antimicrobial agent, has been considered a promising substitute for synthetic preservatives, but its high volatility and poor water solubility limit its practical application. In this study, LEO nanoemulsions were fabricated via high-pressure homogenization using sodium caseinate (SC) and tea polyphenols (TPs) as composite emulsifiers. The preparation process was optimized using a three-factor, three-level orthogonal design, and the physicochemical properties, storage stability, and antibacterial activity were systematically investigated. The optimal preparation conditions were determined as an SC/TP mass ratio of 2:1, homogenization pressure of 70 MPa, and 7 homogenization cycles. The optimized nanoemulsion exhibited a droplet size of 130–210 nm, zeta potential of −30.89 mV, and encapsulation efficiency of 98.61%, with typical shear-thinning behavior and excellent storage stability. The percentage of free LEO remained below 7.5% within 15 days, indicating high stability, and the release behavior followed a zero-order kinetic model. The prepared nanoemulsion showed significant antibacterial activity against Staphylococcus aureus and Escherichia coli, with a minimum inhibitory concentration (MIC) of 62.5 μg/mL for both strains. This study confirms that the SC/TP composite interface can effectively stabilize LEO nanoemulsions, providing a theoretical basis for the development of natural and efficient food preservatives. Full article

Lavender (Lavandula angustifolia Mill.) is a globally significant crop, with Bulgaria maintaining a leading position in essential oil production. This study presents the first comprehensive, multi-regional analysis of commercial lavender plantations in Bulgaria, integrating phenotypic, biochemical, and genetic data. A new field quality index (FQI) was developed to evaluate production efficiency by intergating yield, essential oil quality, and intra-field homogeneity. Genetic profiling of 285 individual plants via Start-Codon-Targeted (SCoT) markers revealed significant genetic diversity and a population structure derived from two primary clusters (Delta K = 2), with high intra-field heterogeneity (64%). Our results demonstrate that peak FQI values are achieved in fields with moderate genetic diversity (genetic homogeneity index HI = 0.6–0.7) and high polymorphic information content (PIC ≥ 0.35), whereas excessive clonal uniformity compromises both yield and phytochemical complexity. The production areas in Northeastern Bulgaria (Shumen, General Toshevo, Shabla) outperformed the traditional areas (Chirpan, Kazanlak), demonstrating higher yields of high-quality essential oil. Furthermore, macroclimatic variations across the studied areas showed significant correlations with the main terpenoid components. Association analysis suggested six SCoT loci as preliminary candidates for Marker-Assisted Selection (MAS), explaining up to 33.97% of the variation in key terpenoids within this study. Furthermore the FQI is proposed as a promising conceptual framework for genome-informed management providing a strategic basis for the sustainable production of high-value lavender oil in a changing climate. The SCoT markers hold potential as useful tools for yield and quality assessment, with the possibility of inclusion in future breeding programs aimed at improving lavender production. Full article