Search Results (105)

The analytical characterization of essential oils (EOs) is often interpreted primarily in terms of biological variability, although analytical conditions may also affect compositional profiling and data comparability. In this study, the influence of chromatographic conditions on gas chromatography–mass spectrometry (GC–MS) profiling was investigated. Five EOs representing chemically diverse plant matrices, including Pistacia lentiscus (resin and stem) and leaf oils from Salvia rosmarinus, Laurus nobilis, and Thymus vulgaris, were analyzed using two capillary columns with different stationary phases: RTX-5MS (5% phenyl-substituted polysiloxane) and CP-Sil 5 CB (100% dimethylpolysiloxane). Comparative analysis revealed reproducible differences in chromatographic profiles and relative peak-area distribution, particularly within terpene-rich regions containing structurally related compounds. The most pronounced effects were observed for highly volatile monoterpenes, which were underrepresented under CP conditions. These findings demonstrate that chromatographic selectivity and column geometry may affect the semi-quantitative representation of EO profiles and contribute to variability in reported compositions. Overall, the results highlight the importance of carefully controlled analytical conditions in EO characterization. Full article

Background/Objectives: In this study, nanoemulsions containing Thymus vulgaris (TV) and Rosmarinus officinalis (RO) essential oils (EOs) were prepared and characterized, and their antibacterial, antifungal, and antibiofilm activities were evaluated against some oral pathogens. Methods: Three nanoemulsions containing 5% TV-EO (F1), 5% RO-EO (F2), and a combination of 2.5% TV-EO and 2.5% RO-EO (F3) were prepared by emulsification followed by high-speed homogenization. Results: Gas chromatography–mass spectrometry coupled with flame ionization detection (GC-MS-FID) analysis revealed linalool (79.51%) as the major constituent of TV-EO and eucalyptol (58.13%), together with camphor (10.80%), as the predominant compounds of RO-EO. All nanoemulsions exhibited nanosized droplets, low polydispersity index (PDI) values (<0.3), and moderate to high colloidal stability. Transmission electron microscopy (TEM) analysis revealed predominantly spherical droplets in all formulations (F1–F3). All formulations exhibited antimicrobial activity against Streptococcus mutans, Lactobacillus acidophilus, Enterococcus faecalis, and Candida albicans. Among the tested formulations, F2 showed the strongest antibacterial activity, whereas F3 exhibited the highest antibiofilm activity against mature S. mutans biofilms, achieving approximately 80% inhibition, comparable to chlorhexidine (CHX). Although F3 possessed the smallest droplet size, its antimicrobial activity was lower than that of F2, suggesting that biological activity was influenced not only by droplet size but also by EO composition. Conclusions: These findings demonstrate the potential of TV-EO and RO-EO nanoemulsions as promising natural alternatives for mouthwash formulations and highlight the importance of EO composition in determining antimicrobial and antibiofilm efficacy. 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

Phytophthora species are among the most destructive plant pathogens worldwide, causing severe losses in agricultural, forest, and natural ecosystems. In recent years, the management of Phytophthora diseases has increasingly shifted toward eco-sustainable strategies, with growing interest in plant-derived extracts, particularly essential oils, as low-risk alternatives to synthetic fungicides. In this study, a structured review was combined with new in vitro assays to assess the antifungal activity of essential oils from Thymus vulgaris (TV-EO) and T. serpyllum (TS-EO) against P. cinnamomi, P. drechsleri, P. cactorum, P. citrophthora, P. nicotianae, P. palmivora, and P. infestans. Literature searches were conducted in April 2025 using the Web of Science and Scopus databases, following PRISMA guidelines, with the search term “Thymus” or “Thyme” and “Phytophthora”. Twenty studies included in the review demonstrated that the activity of Thymus essential oils against Phytophthora species was highly variable and shaped by chemotype, Thymus species, pathogen, and experimental setup. Additional in vitro assays further confirmed a clear dose-dependent inhibitory effect for both TV-EO and TS-EO. TS-EO consistently exhibited stronger activity than TV-EO, likely reflecting its carvacrol-rich chemotype, while thymol-based TV-EO showed lower but still significant inhibition depending on the pathogen species. Overall, these results highlight the potential of Thymus essential oils as eco-friendly tools for the management of Phytophthora diseases. However, the strong dependence on chemotype, pathogen species, and assay conditions underscores the need for standardized testing, detailed chemical characterization, and in vivo validation. Full article

Insects, such as the Mediterranean fruit fly (Ceratitis capitata) and the armyworm (Mythimna unipuncta), and nematodes, including the root-knot nematode (Meloidogyne incognita) and the pine wood nematode (Bursaphelenchus xylophilus), are major agricultural pests. Essential oils (EOs) from aromatic plants are promising botanical pesticides due to their bioactivity. This study evaluated the in vitro effects of EOs from Origanum vulgare, Thymus vulgaris, Ocimum gratissimum, Mentha pulegium, and Cinnamomum cassia, and their main compounds (carvacrol, thymol, eugenol, pulegone, and trans-cinnamaldehyde, respectively), on acetylcholinesterase (AChE) and α- and β-glucosidases using crude enzyme extracts. All EOs inhibited AChE, with no significant effects on glucosidases. M. pulegium EO showed the strongest inhibition in C. capitata (IC₅₀ = 0.022 mg/mL) and B. xylophilus (IC₅₀ = 0.1209 mg/mL), while C. cassia EO was most effective against M. unipuncta (IC₅₀ = 0.0020 mg/mL) and M. incognita (IC₅₀ = 0.0197 mg/mL). In silico analysis revealed selective inhibition of insect AChE by EO-derived compounds, with insignificant effects on electric eel AChE, supporting species-specific interactions. These findings highlight EOs as selective, neurotargeting, and sustainable alternatives to synthetic pesticides. Full article

Finding safe and efficient plant protection measures is one of the major challenges in horticulture. This study evaluated the biological effects of the Thymus vulgaris essential oil and of Bacillus halotolerans and B. velezensis bacterial mixture on strawberry growth and fruit quality properties, as well as on Botrytis cinerea severity. The experiment was conducted in a high-tunnel greenhouse with the strawberry cv. Sonsation. Treatments: (1) Control—untreated; (2) Bacteria—with Bacillus halotolerans and B. velezensis, four times during flowering; (3) Thyme I—T. vulgaris essential oil (EO), four times during flowering; (4) Thyme II—T. vulgaris EO, four applications supplemented by three additional applications during fruit ripening; (5) Biofungicide I—Bacillus subtilis QST 713, four times supplemented by three applications; (6) Biofungicide II—Clonostachys rosea J1446, four times during flowering. In the first year (2023), the highest total yield was observed in Thyme II, and in the second year (2024), the highest total yield was observed in Thyme I. The results did not reveal any visual phytotoxic effect on plant leaves. The average fruit diameter increased from 28 mm up to 31 mm in 2023 and from 35 mm to 39 mm in 2024. The average soluble solids content increased from 9.4 to 11.4 °Brix in 2023 and from 7.2 to 7.7 °Brix in 2024. The highest ascorbic acid content in 2023 was observed in Biofungicide II and Biofungicide I treatments, respectively, 79.9 mg % and 75.4 mg %. Similarly, in 2024, the highest ascorbic acid content was observed in Bacteria, Biofungicide I, and Biofungicide II treatments—39.3–40.2 mg %. In vitro, the lowest B. cinerea severity on strawberry leaves in 2023 was recorded in Thyme I and Thyme II treatments (~6–7%), while in 2024, the severity in these treatments was higher −20–22%. Thyme treatment showed a stable reduction in B. cinerea on leaves in vitro over both years. Full article

Essential oils (EOs) from combined plant materials offer a promising alternative to conventional extraction by enhancing chemical diversity and bioactivity. This study evaluated the chemical composition and insecticidal properties of individual and combined plant EOs from Cymbopogon citratus, Eucalyptus camaldulensis, Eucalyptus lehmannii, Salvia rosmarinus and Thymus vulgaris were evaluated against aphids. Binary and ternary combinations were prepared in equal proportions prior to hydrodistillation. GC-MS analysis revealed significant compositional shifts in EOs from combined plant materials. Major compounds in individual oils included citral (53.11%) and neral (29.14%) in C. citratus, thymol (70.84%) in T. vulgaris, and eucalyptol as the predominant compound in E. camaldulensis (66.51%), E. lehmannii (56.99%) and S. rosmarinus (46.56%), respectively. In the combined oils, the relative abundance of these constituents was altered, and in some cases new constituents were introduced. Principal Component Analysis (PCA) and Hierarchical Cluster Analysis (HCA) revealed that combined plant EOs clustered near their parental oils, indicating compositional inheritance. Contact toxicity assay against Aphis fabae demonstrated enhanced efficacy of the combined oils, with reduced LC₅₀ values (1.39 µL mL⁻¹ for E. camaldulensis + T. vulgaris) and synergistic interactions, indicated by a co-toxicity coefficient (CTC) of 221.58 and elevated synergistic factors. Pearson correlation analysis and Partial Least Squares (PLS) regression jointly identified Acorenone B and thymol as negatively, and caryophyllene as positively correlated compounds, all with relatively high contribution to insecticidal activity, ranking highest with a Variable Importance in Projection (VIP) scores > 1.0. While PLS model had modest predictive power, the integration of these statistical approaches supports the insecticidal potential of combined plant-derived EOS in laboratory bioassays and indicates their relevance to sustainable crop protection. Full article

Sclerotinia sclerotiorum is a soilborne fungal pathogen, and it is a major threat to lettuce production, causing lettuce drop. This study evaluated the antifungal effectiveness of five essential oils (EOs) (Rosmarinus officinalis, R. officinalis var. verbenone, Lavandula hybrida, Origanum majorana, and Thymus vulgaris) at 0.1%, 1%, and 10%, along with their phytotoxic effect in the field on three different crops (lettuce, tomato, and chard) following foliar application. T. vulgaris EO completely inhibited S. sclerotiorum mycelial growth at all tested concentrations. R. officinalis, L. hybrida, and O. majorana also showed full inhibition at 1% and 10%, while R. officinalis var. verbenone achieved 80–100% inhibition. R. officinalis had the least phytotoxic effects, with only a minimal effect on chard at 1%. R. officinalis var. verbenone caused low/moderate phytotoxicity in lettuce and chard but had no toxic effect on tomato. L. hybrida and O. majorana had moderate to low effects, while T. vulgaris was the most phytotoxic, significantly affecting lettuce and tomato at 1%. Further field trials are needed to define EO application protocols toward sustainable lettuce drop management without risks of phytotoxicity. Full article

Thymus, Satureja, and Monarda are three plant genera, belonging to the Lamiaceae family, that are particularly valued for their essential oils (EOs) abundant in phenolic terpenoids. In this study, a botanical characterization of the following eight Eastern European cultivars (some of them newly bred) grown in Ukraine is distinguished: Thymus vulgaris (‘Yalos’, ‘101’), Thymus richardii (‘Fantasia’), Satureja montana (‘Krymsky smaragd’, ‘Lunata’, ‘4-18’), Monarda fistulosa (‘Premiera’), and Monarda × hybrida hort., which is a Monarda didyma × Monarda fistulosa hybrid (‘Tonya’). The EO of those cultivars was obtained and characterized in detail using GC-MS and GC-FID. Additionally, some biological activities of these oils were tested. Antimicrobial activity was verified against Escherichia coli, Staphylococcus aureus, and Candida albicans using disk diffusion and microdilution methods. Furthermore, some preliminary tests were performed on the motility of bull sperm using the CASA system. All the Thymus cultivars were very rich in thymol (57.99–67.62%), and all the S. montana cultivars were very abundant in carvacrol (62.22–75.53%). M. fistulosa cv. ‘Premiera’ contained mainly thymol (49.87%), and M. × hybrida cv. ‘Tonya’ contained both thymol (46.70%) and carvacrol (10.37%). All the tested EOs, as well as thymol and carvacrol, exhibited strong antibacterial and antifungal action with minimal inhibitory concentrations ranging from <0.25–0.5 mg/mL for Satureja, through <0.25–0.5 mg/mL for Monarda, to 0.5–4 mg/mL for Thymus. The EOs, at a concentration of 0.4 µL/mL, exhibited cytotoxicity towards bull spermatozoa when compared to the control sample. Full article

The study focused on essential oils (EOs) of plant origin, which are of great interest to scientists in the context of medical applications due to their biological properties, such as antimicrobial, anti-inflammatory, antioxidant, and anticancer effects. The objective of the study was to determine chemical profiles and biological activities of the essential oils extracted from five mixtures (M1 [Thymus vulgaris, Ammi visnaga, Syzygium aromaticum, Citrus sinensis]; M2 [Thymus vulgaris, Ammi visnaga, Cinnamomum verum, Citrus sinensis]; M3 [Mentha pulegium, Lavandula angustifolia, Zingiber officinale, Citrus sinensis]; M4 [Mentha pulegium, Lavandula angustifolia, Cinnamomum verum, Citrus sinensis]; M5 [Ammi visnaga, Lavandula angustifolia, Zingiber officinale, Syzygium aromaticum]). Each mixture was derived from a blend of four selected plants used in traditional medicine in Mostaganem, Algeria. When selecting the best composition, the interactions between plant components were considered in terms of potential therapeutic benefits. The chemical compositions of the EO mixtures were analyzed using GC-MS. The acute toxicity of the EO mixtures was evaluated in vivo following oral administration. The sensitivity of the microorganisms to the EO mixtures was determined using the agar diffusion method. Virucidal testing was performed using the quantitative suspension method to determine virucidal activity, as described in the European standard for disinfectants used in the medical field. The antioxidant activity of the EO mixtures was evaluated using a model membrane system based on liposomes derived from soybean phosphatidylcholine. Chemopreventive activity was assessed in vitro using cell culture. The main compounds identified were carvacrol and thymol in M1; geranial, cinnamylaldehyde, and carvacrol in M2; pulegone and limonene in M3; geranial and cinnamylaldehyde and limonene in M4; and eugenol and caryophyllene in M5. The selection of the “best” blend depended on the biological activity deemed most critical for the specific application. Specifically, M3, M4, and M5 exhibited the strongest anti-HSV-1, anti-HAdV-5, and anticancer activity, respectively. In contrast, M1, a potent antioxidant, demonstrated the strongest antibacterial and anticancer activity. These results indicate that M1, M3, M4, and M5 EOs have promising applications in the pharmaceutical industry and medical research. Full article

Background: Antimicrobial resistance in oral pathogens drives interest in natural alternatives such as essential oils (EOs). Methods: The chemical composition and in vitro antimicrobial activity of Origanum vulgare, Thymus vulgaris, and Lavandula angustifolia EOs were investigated. Oils were profiled by gas chromatography–mass spectrometry (GC-MS) and tested against Staphylococcus aureus ATCC 29213, Enterococcus faecalis ATCC 29212, Escherichia coli ATCC 25922, and Candida albicans ATCC 10231 using the disc diffusion method (triplicate, 1 µL/disc, ~850–950 µg). Results: O. vulgare oil produced the strongest inhibition against C. albicans (18.4 ± 0.5 mm), T. vulgaris was most active E. coli (13.0 ± 0.5 mm), while L. angustifolia showed negligible activity (6–7 mm). All EO inhibition zones were smaller than those of antibiotics. Conclusions: At clinically relevant doses, Oregano and Thyme oils showed modest antimicrobial effects, whereas Lavender was inactive. However, these findings are limited by the use of ATCC strains, small sample size, and reliance on the disc diffusion method, which provides only qualitative data and does not capture biofilm or host interactions. Future studies should include minimum inhibitory concentrations (MIC)/minimum bactericidal concentrations (MBC) assays, biofilm models, and cytotoxicity testing. AI-assisted GC-MS analysis and automated inhibition zone measurement should be considered as future perspectives to improve reproducibility and translational potential. Full article

Essential oils (EOs) from oregano (Origanum vulgare), rosemary (Salvia rosmarinus), clove (Syzygium aromaticum), thyme (Thymus vulgaris), cinnamon (Cinnamomum verum), and basil (Ocimum basilicum) possess antifungal properties. This study aimed to evaluate their ability to inhibit the growth of fungi isolated from the rot of banana peel (Musa paradisiaca) to control or reduce fungal growth in bananas. The methodology involved preparing dilutions of EOs and inoculating them onto Potato Dextrose Agar (PDA) medium amended with chloramphenicol to prevent bacterial contamination. Fungal species, including Trichoderma spp., Aspergillus spp., Penicillium spp., and Fusarium spp., were isolated, purified, and characterized macroscopically and microscopically. Their growth was assessed ex vivo and the inhibition percentage was measured in vitro. The ex vivo analysis revealed that the severity of fungal infection, ranked from highest to lowest, was as follows: Penicillium spp., Trichoderma spp., Fusarium spp., and Aspergillus spp. The results showed that rosemary and basil oils did not inhibit fungal growth, whereas clove oil, cinnamon, and oregano were effective against the four tested fungi at 800, 400, and 200 ppm, respectively. These findings suggest that certain EOs, including clove, cinnamon, and oregano, have strong antifungal potential and could serve as eco-friendly alternatives to synthetic fungicides in banana postharvest disease management. Full article

This study evaluated the antifungal potential of essential oils (EOs): oregano (Origanum vulgare), rosemary (Salvia rosmarinus), clove (Syzygium aromaticum), thyme (Thymus vulgaris), cinnamon (Cinnamomum verum), and basil (Ocimum basilicum). These oils were tested against fungi isolated from banana peels (Musa paradisiaca). The fungi tested were identified through macroscopic and microscopic analyses and DNA sequencing, after being isolated in potato dextrose agar (PDA) medium modified with 0.05% chloramphenicol. Subsequently, the antifungal properties of the tested essential oils were evaluated in vitro at concentrations of 200, 400, 600, 800, and 1000 ppm prepared in a 0.05% Tween 80 solution. Cinnamon EOs showed the highest antifungal activity, significantly inhibiting the growth of pathogens at a concentration of 400 ppm. Other EOs showed moderate effects at higher concentrations: rosemary inhibited fungal growth at 600 ppm, oregano at 800 ppm, and clove at 1000 ppm. These findings highlight the potential of EOs as eco-friendly alternatives to synthetic fungicides, contributing to the development of sustainable agricultural practices and the post-harvest management of bananas. It is recommended to conduct future research to assess the economic viability and practical impacts of large-scale applications. Full article

In the present work, the antimicrobial efficacy of Thymus vulgaris essential oil (EO) was investigated on Alternaria alternata strain BNR; a paper biodeteriogen was used as a model for a contaminated library. The influence of EO volume and diffusion modality, treatment duration, and inoculum age was evaluated in the vapor phase. In Petri dish screening, the influence of different EO volumes (5, 7.5, and 10 μL) on the microbial growth lag phase was investigated, and the growth inhibition period was established. The most effective treatment (10 μL EO) was then scaled up in a glass airtight container of 2650 cm³; a cold diffusion method was applied in order to quickly reach the maximum concentration of active compounds in the vapor phase. These tests demonstrated that EO efficacy is affected by the inoculum age and the contact time, and that the treatment should be performed as early as is feasible. A mycostatic effect was confirmed to be proportional to the utilized EO volume and independent from the treatment method. The information obtained in the present work will be applied to the set-up of an EO treatment in a library characterized by different levels of air contamination. Full article

Essential oils (EOs) are widely recognized for their antifungal properties, but their efficacy against specific phytopathogenic fungi associated with banana (Musa paradisiaca) rot remains underexplored. This study aimed to evaluate the antifungal potential of EOs from Origanum vulgare, Salvia rosmarinus, Syzygium aromaticum, Thymus vulgaris, Cinnamomum verum, and Ocimum basilicum against five fungal species isolated from infected banana peels. Fungal isolates were obtained using PDA medium supplemented with chloramphenicol and were purified by weekly subculturing. Morphological and microscopic characterization was complemented by molecular identification based on ITS sequencing and phylogenetic reconstruction using Neighbor-Joining and UPGMA methods in MEGA v11. In vitro and ex vivo antifungal assays were performed at EO concentrations ranging from 200 to 1000 ppm. Thyme oil exhibited the strongest inhibitory effect, with complete growth suppression at 1000 ppm. Cinnamon and oregano also demonstrated effective inhibition at 600 ppm, while clove, rosemary, and basil were markedly less effective. Statistical analysis confirmed significant effects of EO type and concentration on fungal growth (p < 0.001). Molecular results showed strong phylogenetic support for isolate identification, with bootstrap values above 93% in most clades. These findings support the selective use of specific EOs as sustainable alternatives to synthetic fungicides in the postharvest management of banana diseases and provide a molecularly supported basis for their targeted application in integrated control strategies. Full article