Search Results (1,417)

Essential oils (EOs) are complex plant-derived products known for their broad-spectrum antibacterial activity. This study aims to evaluate the chemical composition of eight essential oils-EOs (Caryophylli aetheroleum, Menthae aetheroleum, Origani aetheroleum, Rosmarini aetheroleum, Salviae aetheroleum, Melaleucae aetheroleum, Limonis aetheroleum, and Curcumae aetheroleum) and to evaluate their antibacterial and antibiofilm activity against five opportunistic pathogens with biofilm-forming potential (methicillin-susceptible and methicillin-resistant Staphylococcus aureus, Pseudomonas aeruginosa, Enterococcus faecalis, Escherichia coli, and Klebsiella pneumoniae). GC-MS was used to determine the chemical composition of the EOs, and antibacterial activity was evaluated using broth microdilution to determine the minimum inhibitory concentration and minimum bactericidal concentration. Biofilm inhibition was assessed by a crystal violet assay. Oxygenated monoterpenes and phenolic compounds were dominant in Origani, Menthae, Rosmarinus, Melaleucae, and Caryophylli aetheroleum. Potent inhibitory effects against the tested bacterial strains were observed for clove, tea tree, oregano, and rosemary EOs. The antimicrobial efficacy of EOs is closely linked to their chemical composition. Tea tree and oregano EOs exhibited the broadest spectrum of antimicrobial activity, while peppermint and curcuma oils were the least potent. Cytotoxicity thresholds from the literature suggest that some effective EO concentrations exceed safe mucosal limits, particularly in continuous high-dose applications, but short-contact delivery systems or adjunctive use with different agents may mitigate safety concerns. These findings support further investigation into their therapeutic applications in oral health products. Full article

Essential oils (EOs) from aromatic plants are valuable sources of bioactive compounds with potential applications as natural antimicrobials and antioxidants. This study investigated the chemical composition, antimicrobial and antioxidant activities, and in silico pharmacological properties of EOs extracted from Laurus nobilis, Thymbra capitata, and Mentha piperita, three medicinal species traditionally used in northern Morocco. Hydrodistillation yielded 1.12–1.53% oils, and GC–MS analysis revealed distinct chemotypes: L. nobilis was rich in eucalyptol, linalool, methyleugenol, and α-terpinyl acetate; T. capitata was dominated by carvacrol (80.95%), and M. piperita contained high proportions of linalool (57.37%) and linalyl acetate (28.56%). Antimicrobial assays demonstrated strong activity of all oils against Gram-positive and Gram-negative bacteria as well as Candida species, with T. capitata showing the most potent and broad-spectrum effects (MIC 0.073–9.47 mg/mL), attributed to its high carvacrol content. Antioxidant assays (DPPH and ferric reducing power) identified L. nobilis as the most active radical scavenger (IC₅₀ = 0.037 mg/mL), followed by T. capitata, whereas M. piperita displayed weaker activity. PCA confirmed that phenolic monoterpenes drive both antimicrobial and antioxidant potency, while oxygenated terpenes and sesquiterpenes contribute more selectively. ADMET predictions indicated generally favorable absorption and low toxicity, although o-cymene and carvacrol presented potential safety concerns. Molecular docking revealed α-terpinyl acetate as the most versatile ligand, with strong binding to bacterial, fungal, and oxidative enzymes, whereas other compounds exhibited more selective affinities. Collectively, these findings highlight the potential of Moroccan EOs, particularly T. capitata and L. nobilis, as promising natural alternatives to synthetic antimicrobial and antioxidant agents. Full article

Soil water availability and nitrogen (N) deposition critically influence biogenic volatile organic compound (BVOC) emissions, thereby affecting atmospheric chemistry. However, their differential short- and long-term effects remain unclear. Here, Ormosia pinnata and Pinus massoniana seedlings were exposed to three water regimes (moderate drought, MD; normal irrigation, NI; near-saturated irrigation, NSI) and two nitrogen (N0; 0 kg N ha⁻¹ yr⁻¹; N80; 80 kg N ha⁻¹ yr⁻¹) treatments for 20 months. Branch-level BVOC emissions and leaf physiological and biochemical traits were examined after 8 months (short term) and 16 months (long term). In the short term, P. massoniana predominantly emitted α-pinene, β-pinene, and γ-terpinene, whereas O. pinnata emitted isoprene (ISO). After prolonged exposure, ISO became the dominant in both species. Short-term MD and NSI conditions stimulated ISO emissions in O. pinnata, with N80 addition further amplifying this effect. In contrast, long-term treatments tended to suppress ISO emissions in O. pinnata, particularly under N80. Short-term water treatments had no significant effect on monoterpene (MT) emissions in P. massoniana. Under long-term water treatments, N80 suppressed ISO emissions; nevertheless, ISO emission rates (ISOrate) progressively increased with increasing soil water availability. Although leaf intercellular CO₂ concentration (Ci), stomatal conductance (g_s), and photosynthesis-related enzymes exhibited partial correlations with BVOC emissions, an overall decoupling between leaf traits and emission patterns was evident. Our findings demonstrate the significant changes in both BVOC composition and emission magnitudes under the joint effects of water availability and nitrogen deposition, providing important implications for improving regional air quality modeling and BVOC emission predictions. Full article

The essential oil of Torreya nucifera, a coniferous tree native to East Asia, has notable bioactive properties with potential industrial applications. This study examined the effects of seasonal and regional factors on the yield and bioactive constituents of T. nucifera oils in South Korea. Leaf samples were collected in spring (March), summer (June), and autumn (September) of 2023–2024 from three ecologically distinct regions: Jeju Island, Jinju, and Hwasun. Oil yield was stable across seasons (0.9–1.6%) but varied significantly by region (p < 0.05), with Hwasun showing the highest yield. This stability across seasons may reflect the perennial evergreen nature of T. nucifera. Gas Chromatography-Mass Spectrometry (GC–MS) identified 32 volatile components, predominantly monoterpenes (83.7–90.4%) and sesquiterpenes (5.4–11.7%), with D-limonene and 3-carene as key chemical markers. Notably, 3-carene levels were significantly affected by region (p < 0.0001), with higher concentrations in Jeju oils, while D-limonene was influenced by season, region, and their interaction (p < 0.001), reaching peak levels in Hwasun during summer and autumn (up to 70%). Therefore, T. nucifera oil from Hwasun harvested in autumn can be optimised for commercial production by maximising oil yield and enhancing chemical markers. Full article

Premature ovarian failure (POF) is characterized by oxidative stress, cellular senescence, and impaired steroidogenesis, yet current therapies remain limited in effectiveness. Thymol, a natural monoterpene, exhibits antioxidant and anti-inflammatory properties. Network pharmacology and molecular docking identified multiple potential targets, notably the Janus kinase 1 (JAK1)-signal transducer and activator of transcription 3 (STAT3) pathway. In tert-butyl hydroperoxide (t-BHP)-induced human granulosa-like tumor cells (n = 3), 40 μg/mL thymol increased cell viability by approximately 45%, restored superoxide dismutase, catalase, and glutathione peroxidase activities to nearly twice those of the model group, and reduced reactive oxygen species accumulation by about 35% (p < 0.05). It also decreased senescence markers p53, p21, and p16 by 40–60% and inhibited JAK1–STAT3 phosphorylation (n = 3, p < 0.05). In aged pregnant mice (n = 4 per group), thymol increased viable fetus numbers by about 40%, elevated serum estradiol and progesterone levels to 1.6–1.8-fold of aged controls, and downregulated ovarian aging markers (p < 0.05). Collectively, these findings indicate that thymol mitigates oxidative stress-induced ovarian aging by modulating JAK1–STAT3 signaling and restoring steroidogenic function, supporting its potential as a natural candidate for delaying ovarian senescence. Full article

The Mediterranean ecosystem is characterized by marked seasonality; it is composed of species such as shrublands that are subjected to high levels of water and thermal stress, making these species an important source of secondary metabolites of significant chemical and ecological interest. In this work, 21 plants were selected from the Mediterranean scrub. These abundant and characteristic representations of the ecosystem produce a total of 197 terpenes. The majority of these are monoterpenes (46.70%), followed by sesquiterpenes (38.07%), with a minority of diterpenes (5.53%) and triterpenes (10.15%). Tetraterpenes accounted for only 0.5% of the total compounds in the species studied, corresponding to only 1%. The major terpenes include 1,8-cineole, terpinen-4-ol, α-terpineol, borneol, camphor, γ-terpinene, limonene, linalool, o-cymene, α-tujene, α-pinene, β-pinene, sabinene, myrcene, β-phellandrene, and β-caryopylene. Species such as Pistacea terebinthus, Rosmarinus officinalis, Cistus ladanifer, Myrtus communis, Lavandula stoecha, and Thymus mastichina contain the most terpenic compounds in their chemical composition. Furthermore, these metabolites are involved in various biological functions, including antimicrobial, antioxidant, neuroprotective, antibacterial, cardiovascular, analgesic, antitumor, and insecticidal activities, among others. Various terpenes present in Mediterranean scrub species, such as 1,8-cineole, α-pinene, limonene, borneol, and terpinen-4-ol, have demonstrated synergistic effects that enhance their antimicrobial, insecticidal, and neuroprotective properties. These interactions between compounds make the natural extracts more effective than they would be individually, increasing their therapeutic and biotechnological value. The synergism among terpenes suggests a promising approach for developing more effective and sustainable phytotherapeutic products. Full article

This study investigated the impact of harvest season and extraction method on the yield, composition, and bioactivity of essential oils (EOs) from wild Rosmarinus officinalis L. plants collected in Algeria. Oils were obtained by hydro distillation (HD), steam distillation (SD), and microwave-assisted distillation (MD) across four seasons and characterized by GC–MS. Camphor, α-pinene, camphene, and 1,8-cineole were consistently dominant, with spring oils, particularly those extracted by microwave-assisted distillation, showing the highest enrichment in oxygenated monoterpenes (up to 59.6%). Functional assays revealed clear seasonal variation, whereas spring oils exhibited the strongest antioxidant capacity, with a FRAP value of 4.63 µg/mL, approaching that of the synthetic standard BHA (6.89 µg/mL), alongside notable anti-inflammatory effects. Antimicrobial screening indicated selective inhibition of Escherichia coli and Candida albicans, while Pseudomonas aeruginosa and Bacillus subtilis remained resistant. Acute toxicity evaluation confirmed safety at 2000 mg/kg. These findings demonstrate that ecological timing and extraction strategy critically determine rosemary EO properties and establish quantitative benchmarks for their pharmaceutical and industrial valorization. Full article

Juniperus is one of the vital genera of the Cupressaceae family; many Juniperus species (juniper) have served as traditional folk medicines. The aims of this study are to analyze its chemical composition and to evaluate the mosquito larvicidal activity of leaf essential oil and its constituents. The constituents of leaf essential oil were analyzed by GC-MS. Leaf essential oil is mainly composed of hydrocarbon monoterpenes and, secondly, oxygenated monoterpenes. Leaf essential oil exhibited good brine shrimp lethality activity, which is highly correlated with larvicidal activity, with the LC₅₀ of 49.89 μg/mL. Leaf essential oil showed a strong mosquito larvicidal activity against two Dengue vector mosquitoes, Aedes aegypti and Ae. albopictus, the LC₅₀ values for both species were lower than 50 μg/mL. Among the major constituents of leaf essential oil, compounds limonene, sabinene, and β-myrcene also exhibited a significant larvicidal effect. Through these investigations, it is expected that leaf essential oil from J. chinensis var. kaizuka and its constituents are of potential use as environmental control chemicals against Dengue vector mosquitoes. Full article

Essential oils (EOs) are mixtures of aromatic and volatile compounds. Owing to their biological properties, they are of increasing interest in the food industry as a viable alternative to natural additives. The objective of this study was to evaluate the in vitro biological activity of EOs extracted from eight plant species growing in northeastern Peru in relation to their chemical composition. EOs were extracted by hydrodistillation and evaluated for antibacterial activity, antioxidant capacity, and total phenolic content. Chemical characterization was performed by gas chromatography coupled with mass spectrometry (GC-MS), and the extraction yield was evaluated in two seasons of the year. The extraction yields varied from 0.04 to 1.50%, according to the species, with greater seasonal variation observed during the rainy season. The chemical compounds identified included monoterpene and sesquiterpene hydrocarbons, oxygenated monoterpenes and sesquiterpenes, benzene derivatives, fatty acids and derivatives, diterpenes, and phenylpropanoids. The EOs of Magnolia jaenensis, Piper amalago, Piper glabribaccum, and Tesaria integrifolia demonstrated high antibacterial activity against the Gram-positive pathogen Staphylococcus aureus, while the other EOs, such as Magnolia manguillo and Zanthoxylum fagara, showed intermediate activity. However, all EOs had low performance against the Gram-negative bacteria Escherichia coli and Salmonella enteritidis. The EOs from T. integrifolia, Piper aduncum, M. manguillo, M. jaenensis, and P. glabribaccum had high antioxidant activity. The EOs with the best biological performance were T. integrifolia, M. jaenensis, and P. glabribaccum. Full article

Cinnamomum burmanni (Nees & T. Nees) Blume, a member of the Lauraceae family, exhibits adaptability to diverse environmental conditions by synthesizing a diverse array of specialized secondary metabolites, including terpenoids and cinnamaldehyde. Nevertheless, the molecular mechanisms underlying the chemical diversity in the leaves of C. burmanni and their remarkable adaptation to subtropical and tropical forests in South China have not been thoroughly investigated. This research integrates transcriptomic and proteomic analyses across five chemotypes of C. burmanni, namely, the borneol-type (BORCB), cinnamaldehyde-type (PROCB), eucalyptol-type (EUCCB), phytol-type (PHYCB), and chlorophyllinol-type (CARCB), by means of the Nanopore and Nano UPLC-MS/MS sequencing data. The findings indicate that PROCB demonstrates an up-regulation of the phenylpropanoid pathway (such as PAL, C4H, PR proteins), which is associated with biotic stress defense. In contrast, the terpenoid-dominated chemotypes (BORCB, EUCCB, PHYCB) prioritize the biosynthesis of monoterpenes and diterpenes as well as redox homeostasis. Protein–protein interaction networks highlight functional specialization; BORCB up-regulates the expression of enzymes GGPPS and TPS2, which are involved in monoterpene production; PHYCB enhances the activity of diterpene synthases (CPS, KSL) and chloroplast retrograde signaling; EUCCB activates SOD/GST to mitigate oxidative stress. PROCB induced defense hubs (NPR1, WRKY33) mediated by salicylic acid and pathogenesis-related proteins. The study establishes a comprehensive multi-omics resource for a gene–protein–metabolite framework, elucidating the mechanisms of stress resilience of C. burmanni in South China. 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

Background/Objectives: Carvacrol and thymol are monoterpenes present in phenolic-rich essential oils extracted from aromatic plants that exhibit antimicrobial activity. This study evaluates the antiprotozoal effect of carvacrol, thymol and their precursor, p-Cymene, against Giardia lamblia and investigates their mechanism of action and cytotoxicity profile. Methods: G. lamblia susceptibility, cell viability, swelling and adhesion abilities following application of carvacrol, thymol and p-Cymene were assessed. Ultrastructural changes were evaluated using electron microscopy. Cytotoxicity was determined in mammalian cell lines (murine macrophages RAW 264.7 and bovine aortic endothelial cells) exposed to the same IC₅₀ concentrations effective against G. lamblia. Results: Carvacrol and thymol led to significant inhibition of G. lamblia trophozoite proliferation (IC₅₀ ≅ 50 µg/mL). After 7 h of incubation, total cell number decreased by 30% (p < 0.01) with carvacrol and by 50% (p < 0.001) with thymol, accompanied by reduced motility and adhesion (<20% attached cells). At IC₅₀ concentrations, G. lamblia trophozoites exposed to carvacrol and thymol underwent considerable ultrastructural alterations (e.g., aberrant-shaped cells, mitochondrial swelling and autophagosomal structures). Reduced trophozoite motility and adhesion capacity were also observed. In mammalian cells, thymol showed no significant cytotoxicity, whereas carvacrol significantly reduced viability in both cell lines. In contrast, p-Cymene showed no antigiardial activity. Conclusions: Our data suggests that carvacrol and thymol disrupt G. lamblia trophozoite integrity, possibly through alterations in membrane permeability and osmoregulatory processes. In conclusion, these compounds reveal in vitro antigiardial activity, supporting their potential as antigiardial drugs. Full article

Background/Objectives: Kozan Misket orange (Citrus sinensis L.) is a regional Turkish cultivar valued for its unique flavor, yet the mechanisms underlying its aroma development remain unclear. Volatile compounds are key contributors to citrus sensory quality, and β-glucosidase is involved in releasing glycosidically bound aroma precursors. However, no previous study has examined the interaction between enzyme activity and volatile production during maturation in this cultivar. This study aimed to characterize the dynamic changes in volatile composition and β-glucosidase activity across different maturation stages of Kozan Misket orange. Methods: Fruits were harvested at three maturity stages (green, green–yellow, yellow). Physicochemical traits (TSS, TA, TSS/TA), volatile profiles (HS-SPME/GC-MS), and specific β-glucosidase activity were analyzed. Volatile compounds were identified, quantified, and compared across stages. Results: A total of 47 volatile compounds were identified, with monoterpenes dominating at all stages. D-limonene was the most abundant compound, exceeding 86% of total volatiles. Total volatile content increased with maturation, particularly monoterpenes and sesquiterpenes, whereas oxygenated monoterpenes (e.g., linalool, 4-terpineol, α-terpineol) declined at full maturity. Specific β-glucosidase activity decreased markedly from 20.15 to 8.25 U mg⁻¹ protein. This shift suggests that bound precursors contribute more to early-stage aroma release, while later-stage aroma accumulation may rely on metabolic conversions. Conclusions: This study provides the first integrated insight into aroma development in Kozan Misket orange, revealing a dual-phase mechanism linking volatile formation and β-glucosidase activity. These findings clarify cultivar-specific flavor development and offer guidance for harvest optimization and flavor management. Full article

This study evaluated the efficacy of essential oils (EOs) for the postharvest management of anthracnose caused by Colletotrichum gloeosporioides in mango. EOs from Cinnamon (Cinnamomum zeylanicum), Oregano (Origanum vulgare), Rosemary (Salvia rosmarinus), and Black pepper (Piper nigrum) were chemically characterized using gas chromatography–mass spectrometry (GC–MS). The main compounds identified included eugenol, methyl eugenol, carvacrol, and eucalyptol, all recognized for their antifungal and antioxidant properties. In vitro assays showed that cinnamon and black pepper EOs significantly inhibited mycelial growth of C. gloeosporioides at all tested concentrations, whereas rosemary EO exhibited lower efficacy. In vivo experiments confirmed that all tested EOs significantly reduced disease severity in mango fruits compared to the control. Overall, the antifungal activity of EOs was dose-dependent and strongly influenced by their chemical complexity and synergistic interactions among major and minor components. These findings highlight the relevance of oxygenated monoterpenes, hydrocarbon monoterpenes, and sesquiterpenes as candidate groups for developing sustainable alternatives for the control of C. gloeosporioides in mango production. Full article

Background/objectives: Cellular senescence is a hallmark of aging that contributes to tissue dysfunction and age-related diseases. This process is characterized by the activation of the cyclin-dependent kinase inhibitor p16^INK4A and the secretion of pro-inflammatory factors collectively known as the senescence-associated secretory phenotype (SASP). In this study, we used human lung-derived cells, including A549 and IMR90 fibroblasts, to identify bioactive compounds from the roots of Liquidambar formosana that suppress p16^INK4A activity and attenuate SASP expression. Methods: Bioactivity-guided isolation was performed to obtain target compounds. The structures of the new compounds were elucidated using extensive 1D and 2D NMR spectroscopic analyses as well as high-resolution mass spectrometry. All isolated compounds were evaluated for their ability to inhibit p16^INK4A, a key regulator of the cell cycle and an important tumor suppressor protein. Results: Two previously undescribed monoterpenoids (1 and 2), characterized as cinnamic acid esters with a monoterpene-derived core, were isolated from the roots of L. formosana, along with six known compounds (3–8). Notably, compound 3 exhibited promising inhibition of p16^INK4A with an IC₅₀ value of 3.9 μM. Furthermore, this compound attenuated the senescence phenotype, as demonstrated by β-galactosidase staining and RT-qPCR analysis. This represents the first report identifying bioactive monoterpenoids from L. formosana that inhibit aging-related biomarkers such as p16^INK4A. Conclusions: These results suggest that cinnamic acid-conjugated monoterpenoids may serve as interesting lead structures for the development of agents targeting the p16^INK4A pathway for the treatment of aging-associated diseases. Further studies will be required to clarify the mechanisms of action of this compound and to evaluate its in vivo efficacy. Full article