Search Results (123)

Plant-derived antimicrobial compounds are emerging as promising alternatives to synthetic preservatives in the food industry due to their efficacy against a broad spectrum of pathogenic and spoilage microorganisms, as well as their consumer acceptance. This review critically examines the main classes of bioactive phytochemicals, including essential oils, polyphenols, alkaloids, terpenoids, and saponins, comparing their relative antimicrobial effectiveness and highlighting representative examples. Notably, essential oils rich in thymol or carvacrol have shown strong inhibitory activity against Listeria monocytogenes and Salmonella spp., while polyphenols and alkaloids exhibit moderate to strong activity depending on concentration and food matrix. Their mechanisms of action include cell membrane disruption, inhibition of key enzymes, and interference with DNA or protein synthesis. Applications in food systems (i.e., incorporation into coatings, emulsions, or controlled-release formulations) demonstrate potential for extending shelf life and enhancing safety. However, practical implementation is challenged by matrix-dependent efficacy, compound stability, sensory impact, and regulatory and toxicological considerations. By synthesizing current knowledge, identifying the most promising compound classes, and highlighting key limitations, this review provides a critical framework to guide future research and the development of effective, sustainable natural preservatives in the food industry. Full article

The identity of oregano used as a medicinal plant and culinary spice remains controversial due to frequent confusion between Origanum vulgare L., native to the spontaneous flora of Romania (mainly subsp. vulgare), and chemically distinct oregano taxa commercially marketed under the generic name “oregano”, often associated with phenolic-rich chemotypes attributed to O. vulgare subsp. hirtum (Link) A.Terracc. The present study aimed to clarify the morphological and chemotaxonomic differences between wild Romanian populations of O. vulgare and commercially available oregano-type plant material, using authenticated O. vulgare subsp. hirtum as a comparative reference. Comparative botanical analysis was performed on wild and cultivated material, followed by thin-layer chromatography (TLC) screening and gas chromatography–mass spectrometry (GC–MS) analysis of essential oils obtained by hydrodistillation. Morphological examination revealed stable differences between wild O. vulgare subsp. vulgare and commercially sourced material in stem habit, leaf morphology, inflorescence structure, corolla coloration, and aroma. TLC screening showed the absence of phenolic derivatives in extracts from wild O. vulgare subsp. vulgare and authenticated O. vulgare subsp. hirtum, while intense thymol-related zones were detected exclusively in plants derived from commercial seeds labeled as O. vulgare. GC–MS analysis confirmed these findings, demonstrating the absence of phenolic monoterpenes in wild populations and their high abundance, particularly thymol and carvacrol, in commercial samples. These results highlight significant discrepancies between authentic wild oregano and commercially marketed plant material, emphasizing the need for rigorous botanical authentication in ethnobotanical, phytochemical, and pharmacological research. Full article

Eupatorium fortunei Turcz. (E. fortunei), a member of the Asteraceae family, is a widely utilized traditional medicinal herb in China. Historically, it has been employed to treat conditions such as influenza, nausea, anorexia, and various ailments associated with “pathogenic dampness”. To the best of our knowledge, this study presents the first systematic review of recent research on E. fortunei, based on a comprehensive literature search across both Chinese and international databases, including Web of Science, PubMed, SciFinder, and CNKI. The review encompasses its botanical characteristics, traditional applications, phytochemical composition, pharmacological properties, and toxicological profiles. Current research reveals a diverse array of phytochemicals in E. fortunei, with 162 compounds identified to date, including thymol derivatives, terpenoids, alkaloids, benzofurans, fatty acids, and other bioactive constituents. These compounds exhibit a broad spectrum of pharmacological activities, encompassing anti-cancer, anti-viral, anti-fungal, anti-inflammatory, and anti-diabetic effects. Among these, thymol derivatives and benzofurans emerge as the most prominent bioactive compounds, demonstrating potent cytotoxic effects against various tumor cell lines. Although E. fortunei is generally considered safe, certain pyrrolizidine alkaloids (PAs) present potential hepatotoxic risks, which can be mitigated through appropriate dosage control and formulation optimization. As a valuable traditional Chinese medicinal herb, E. fortunei exhibits substantial therapeutic potential. In conclusion, this review provides a comprehensive and systematic overview of current research on E. fortunei, offering scientific evidence and guidance for its rational development and clinical application. Full article

The natural product composition of the hexane and methyl tert-butyl ether extracts of Dittrichia viscosa roots was examined. Eight terpenoids were identified by nuclear magnetic resonance (NMR) and high resolution mass spectroscometry (HRMS) techniques, four of which (1, 5, 6 and 8) are reported here for the first time as natural products. Of these eight compounds, four are thymol derivatives (1–4), two are guaianolides (5 and 7) and two are himachalanes (6 and 8). Additionally, the occurrence of himachalanes in this species is reported for the first time. Furthermore, a study of the potential plant protection effects of some of these natural products and the chemical derivative 6a was carried out. Promising preliminary results were obtained for compounds 1–3 and 6a as antifeedant agents against Spodoptera littoralis; 1–3 and 5 against Myzus persicae; 1–3 against Rhopalosiphum padi; and 4 as nematicide against Meloidogyne javanica. Finally, the phytotoxic activity of compounds 4, 5 and 6a against the monocotyledonous species Lolium perenne was also proven. 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

Monoterpenes (thymol, carvacrol, menthol) and phenylpropanoids (eugenol and cinnamaldehyde) and their related derivatives are naturally occurring bioactive compounds found in essential oils (EOs) and have attracted considerable interest as anticancer agents; however, their direct therapeutic use in cancer treatment is often limited by factors such as low bioavailability, moderate potency, and lack of target specificity. Recent studies have demonstrated that rational structural modification of these EO scaffolds can substantially enhance their anticancer potential. This review critically evaluates the different structural modification strategies applied to EO components, including pharmacophore hybridization, heterocycle incorporation (e.g., triazoles, oxadiazoles, chalcones), esterification, halogenation, metal complexation, and nanoparticle conjugation. The review compares these approaches across the selected EO components, highlighting their impact on anticancer potency, and mechanistic relevance. However, the current evidence base is heterogeneous, with considerable variability in experimental conditions, selectivity assessments, and reliance on in vitro or in silico findings, which limits direct cross-study comparisons and translational interpretation. Overall, structural modification of EO components represents a promising strategy for generating novel anticancer lead compounds, but future progress will depend on standardized biological evaluation, rigorous in vivo validation, and comprehensive pharmacokinetic and toxicity profiling to realistically define their clinical potential. Full article

Toxic Cd (cadmium) pollution in agricultural soil has been drawing global attention. Using exogenous regulators to detoxify Cd in crops is a promising approach to alleviate Cd stress and prevent Cd accumulation in human bodies through the food chain. Natural compounds show great potential due to their environmentally friendly properties. We have found that thymol (a plant-derived natural compound) protects plants from Cd stress. To extend the application of thymol in agriculture, further studies are needed to understand the detailed mechanism by which thymol induces Cd tolerance and limits Cd accumulation in crops. In this study, hydroponic experiments using the roots of Brassica rapa L. exposed to a nutrient solution containing Cd (3 µM) and thymol (15 µM) were conducted to investigate the mechanism of thymol-induced Cd tolerance. Pot experiments with different vegetables (B. rapa, water spinach, and pepper) growing in Cd-polluted soil (0.5 µM Cd) were carried out to investigate the role of foliar spraying of thymol (15 µM) in decreasing the Cd content in vegetables. In the hydroponic study, thymol enhanced the shoot fresh weight and root fresh weight of B. rapa by 313% and 125%, respectively, upon Cd exposure. Thymol detoxifies Cd-induced ROS accumulation by increasing the activity of superoxide dismutase (SOD), peroxidase (POD), and catalase (CAT) in B. rapa by 8.9–33.6%, 12.9–31.6%, and 57.8–135%, respectively. The thymol-activated AsA-GSH (ascorbic acid-glutathione) cycle also contributed to the decrease in ROS level. Thymol also reduced the Cd content in the shoots and roots of B. rapa by 55.7% and 46.6%, respectively, which was associated with the modulation of the expression of a set of genes accounting for Cd accumulation and transport. In the pot study, foliar spraying of thymol significantly decreased the Cd content in various vegetables, including leafy vegetables (B. rapa and two water spinach varieties, with leaf Cd decreasing by 40.5–45.9%) and solanaceous fruits and vegetables (three pepper varieties, with fruit Cd decreasing by 26.9–35.8%), which was accompanied by a growth-promoting effect. The results from this study elucidate the multifaceted function of thymol in helping vegetables detoxify Cd and decrease Cd bioaccumulation, shedding new light on developing thymol as a potential plant regulator to safeguard agroproduct security in Cd-polluted environments. Full article

Background/Objectives: Thymol (THY) is widely used in oral care products for its antimicrobial and anti-inflammatory activity, but data on its cytocompatibility, potential differential effects on oropharyngeal-derived cells, and mucosal irritation under prolonged exposure remain limited. This study evaluated THY’s effects on healthy human gingival fibroblasts (HGF-1) and pharyngeal carcinoma (Detroit-562) cells after 24 h exposure, together with its irritation potential in ovo. Methods: Cells were treated with THY (100–300 µM) for 24 h. Cellular viability (MTT), morphology, mitochondrial alterations (MitoTracker™/Hoechst 33342), mitochondrial membrane potential (JC-1), and apoptosis/necrosis (AO/PI) were assessed. Clonogenic assays evaluated long-term proliferative capacity. Lastly, irritation score was examined using the HET-CAM assay at 300 µM. Results: THY produced a dose-dependent viability decrease in both lines, with HGF-1 viability remaining ≥75% and Detroit-562 reduced to ~68% at 300 µM. Morphology, mitochondrial staining, JC-1 ratios, and AO/PI imaging showed progressive apoptotic features, more evident in Detroit-562 cells. Clonogenic capacity increased slightly in HGF-1 at 100 µM and declined to ~75% at 300 µM, whereas Detroit-562 colonies decreased from ~68% to ~40% across the dose range. Additionally, THY (300 µM) showed no irritation in the HET-CAM assay. Conclusions: THY demonstrated acceptable cytocompatibility in gingival fibroblasts, stronger inhibitory effects on carcinoma cells at higher concentrations, and no acute irritation in ovo. These findings support THY’s safe use within defined concentration limits and justify further evaluation in advanced oral tissue models. Full article

Pseudomonas aeruginosa elastase LasB accelerates refrigerated food spoilage through proteolytic degradation of muscle and milk proteins. While Marrubium vulgare essential oil terpenes exhibit antimicrobial activity, their weak potency and nonspecificity limit direct food preservation applications. This computational study aimed to rationally redesign terpene scaffolds into predicted selective LasB inhibitors. A virtual library of 635 terpene–peptide–phosphinic acid hybrids (expanded to 3940 conformers) was evaluated using consensus molecular docking (Glide/Flare) against LasB (PDB: 3DBK) and three human off-target proteases. Top candidates underwent duplicate 150 ns molecular dynamics simulations with MM/GBSA binding free-energy calculations. Computational screening identified thymol–Leu–Trp–phosphinic acid as the lead candidate with predicted binding affinity of −12.12 kcal/mol, comparable to reference inhibitor phosphoramidon (−11.87 kcal/mol), and predicted selectivity index of +0.12 kcal/mol representing a 2.3 kcal/mol advantage over human proteases. Molecular dynamics simulations indicated exceptional stability (98.7% stable frames, 0.12 Å inter-replica RMSD) with consistent zinc coordination. Structure–activity analysis revealed phosphinic zinc-binding groups (+1.57 kcal/mol), Leu–Trp linkers (+2.47 kcal/mol), and phenolic scaffolds (+1.35 kcal/mol) as predicted optimal structural features. This in silico study provides a computational framework and prioritized candidate set for developing natural product-derived food preservatives. All findings represent computational predictions requiring experimental validation through enzymatic assays, food model studies, and toxicological evaluation. Full article

Background: Thymol, a natural phenol with antimicrobial and antioxidant activities, and its derivatives offer promising scaffolds for antimalarial drug development, potentially helping overcome resistance. Materials and Methods: In this study, thymol derivatives were synthesized and assessed as antiplasmodial agents against both resistant and sensitive strains of P. falciparum, as well as Plasmodium knowlesi. The ligand molecules were assessed with Plasmodium falciparum chloroquine resistance transporter (PfCRT)’s potential using in silico molecular docking and ADMET analysis. The parent compound, thymol, was chemically modified through esterification and conjugation with hydroxybenzoic acid and cinnamic acid derivatives to generate analogs with varied substitution patterns. Results: The findings showed that among seven successfully synthesized thymol derivatives, compounds 4 and 6 exhibited notable potency against Plasmodium falciparum 3D7 (EC₅₀ = 6.01 ± 1.7 µM and 6.8 ± 1.1 µM, respectively) with high SI values (16.5 and 14.6, respectively), indicating improved selectivity relative to thymol. The cytotoxicity evaluation against HCF mammalian cells revealed that most thymol derivatives were non-toxic, with CC₅₀ values greater than 99 µM, except for compound 3 (CC₅₀ = 71.4 ± 4.5 µM) and compound 1 (CC₅₀ = 58.4 ± 2.3 µM), which exhibited moderate cytotoxic effects. The molecular docking results showed that compounds 3 (−8.4 kcal/mol), 4 (−8.3 kcal/mol), and 6 (−8.3 kcal/mol) exhibited strong binding affinities toward the PfCRT protein. Conclusions: Therefore, thymol derivative compounds 4 and 6 exhibited stronger antiplasmodial activity in vitro against P. falciparum and P. knowlesi with safety profiles against mammalian cells, targeting PfCRT, highlighting their potential as lead antimalarial candidates. Full article

Background/Objectives: This research was conducted to evaluate the antimicrobial activity of four molecules present in essential oils (thymol, terpinen-4-ol, citral, and E-2-dodecenal), complementing the study with the observation of structural damage caused by the contact of these compounds with microorganisms. Methods: The micro dilution in plates method was used to determine the minimum inhibitory concentration, using different concentrations of metabolites in contact with the microorganisms. Optical Microscopy was used to observe structural damage in yeasts, while Scanning Electron Microscopy (SEM) was used for bacteria. Results: In determining the minimum inhibitory concentration, very good activity was observed for all microorganisms at concentrations below 500 µg/mL or 0.05% w/w. In microscopic tests, we can observe three consequences of contact with the molecule to a greater or lesser extent. First, there is a clear decrease in the concentration of microorganisms. Second, we observe damage to the cell membrane. Finally, there are structural changes within the cytoplasm. Conclusions: This study demonstrated that the four metabolites possess good antimicrobial activity, in some of the tests they were even very close to the control antibiotics’ activity. Structural observations show that the activity can be explained by several factors. Many essential oils contain some of the molecules used, so their presence in nature could be a marker of antimicrobial activity. 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

Plant-parasitic nematodes (PPNs) pose a serious threat to global agriculture by reducing both yield and quality in high-value crops. Although chemical nematicides provide rapid control, their application is increasingly restricted due to environmental pollution and toxicity to non-target organisms. These limitations have increased the search for sustainable and environmentally friendly alternatives. Plant-derived essential oils (EOs) have emerged as promising nematicides due to their sustainable nature and bioactivity. EOs of plant families such as Lamiaceae, Amaryllidaceae, Lauraceae, Apiaceae, and Zingiberaceae have been reported to exhibit nematicidal activity. Their major constituents include linalool, thymol, carvacrol, diallyl disulfide, cinnamaldehyde, γ-terpinene, cumin aldehydes, eucalyptol, and spathulenol. EOs suppress nematode populations through mechanisms including inhibition of egg development, increased larval mortality, and reduction in root gall formation. However, field efficacy can be limited by chemical composition variability, volatility, and phytotoxicity. Advanced formulation techniques, such as micro and nano-encapsulation, can improve EO stability, controlled release, and consistent efficacy. Future research should focus on clarifying synergistic and antagonistic interactions among EO constituents, optimizing field applications, and integrating EO-based products with other sustainable strategies. In addition, studies should prioritize standardizing extraction methods, conducting chemical profiling, and verifying their efficacy and safety through repeated field trials in various agricultural systems. In conclusion, plant-derived EOs represent promise as a sustainable method of managing nematodes and contribute to sustainable agriculture. Full article

Essential oil-derived compounds such as eugenol, thymol, cinnamaldehyde, and carvacrol exhibit potent antimicrobial and anti-inflammatory properties, making them promising candidates for therapeutic and industrial applications. This review examines the current evidence regarding the mechanisms of action, efficacy, and ability to disrupt quorum sensing and biofilm formation of essential oil-derived compounds against a broad spectrum of Gram-positive and Gram-negative bacteria, including multidrug-resistant (MDR) strains. The anti-inflammatory activity of these compounds is also highlighted, with emphasis on their modulation of key signaling pathways such as nuclear factor-kappa B (NF-κB) and mitogen-activated protein kinases (MAPKs), and their ability to downregulate pro-inflammatory cytokines. However, challenges persist, including cytotoxicity at high concentrations, chemical instability, poor water solubility, and variable pharmacokinetics. Advanced delivery systems such as nano encapsulation and synergistic formulations offer potential strategies to overcome these limitations. This review highlights both the therapeutic potential and the current limitations of these natural compounds, emphasizing the need for continued research to translate preclinical findings into clinical applications. Full article

NADESs represent a modern class of extraction media that align with the principles of green chemistry. They are considered non-toxic and biodegradable, but relatively little is known about their biological activity. This study investigated the antioxidant, antibacterial, and antifungal properties of 40 NADESs. The systems were developed from primary (PRIM) based on choline chloride (ChCl), and specialized (HEVO) plant-derived metabolites, particularly based on thymol and menthol. Their antioxidant activity was evaluated using spectrophotometric tests. The antimicrobial activity was evaluated by the disk diffusion method. The data obtained were analyzed using principal component analysis (PCA) and partial least squares discriminant analysis (PLS-DA). NADESs based on PRIM exhibited negligible antioxidant activity and relatively low antimicrobial activity. By contrast, NADESs containing HEVO, particularly thymol-based systems, indicated significant antioxidant activity, with stronger activity observed at higher molar proportions of thymol. In the 1,8-cineole:thymol system, ABTS activity ranged from 167.37 ± 24.17 to 861.25 ± 33.03 mg Trolox equivalents/mL NADES (molar ratios 9:1 and 1:9, respectively). The 1,8-cineole:thymol system (1:9) also showed strong antimicrobial activity, with a maximum inhibition zone of 39.33 ± 2.52 mm against Staphylococcus aureus. In summary, NADESs based on HEVO exhibit significantly stronger biological activity than those containing only PRIM. Full article