Search Results (281)

This study evaluated the use of HDES for omega-3 recovery from by-products of Octopus maya, an endemic species of the Yucatán Peninsula, Mexico. A 2 × 3 × 2 factorial design was applied to assess the effect of: (1) the hydrogen bond acceptor (HBA, menthol or eucalyptol) of hydrophobic deep eutectic solvents (HDES) with oleic acid as the hydrogen bond donor; (2) the molar ratio (MR) (1:1, 1:2, or 2:1); and (3) ultrasound-assisted extraction time (ET) (30 or 60 min) in omega-3 equivalents (EO3, mg/mL), determined by UV–Vis spectrophotometry and viscosity characterization to the Octopus maya extracted samples (n = 2), reported as $\overline{x}$ ± SD. The effects of the factors studied were analyzed by a DOE methodology with Minitab^® (version 18). Samples with the highest omega-3 were selected and their composition was confirmed by FTIR, Raman spectroscopy and gas chromatography. Eucalyptol at a molar ratio of 1:2 and an extraction time of 30 min yielded the highest OE3 (0.70 mg/mL). The statistical analysis revealed that the extraction of omega-3 determined by UV–Vis spectrophotometry was significantly influenced by the triple interaction of HBA × MR × ET (p < 0.05), indicating that extraction performance depends on the combined effect of solvent composition and processing conditions. All extracts showed Newtonian behavior with viscosities between 0.011 and 0.036 Pa·s, with eucalyptol formulations presenting the lowest values (0.011–0.023 Pa·s). Fatty acid profile allowed to quantify C16:0; C18:0; C18:1 n-9; C18:2 n-6; and C18:3 n-3, palmitic, stearic, oleic, linoleic and linolenic fatty acids, respectively, showing greater affinity for polyunsaturated fatty acids, mainly omega-6 (23.45–27.91%), and lower affinity for saturated fatty acids such as palmitic and stearic acids, indicating HDES as a sustainable alternative for selective extractions. Full article

The chemical composition of basil essential oil is influenced by plant developmental stage, which alters the relative distribution of volatile constituents and their functional properties. In this study, we investigated developmental-stage-dependent changes in the essential oil composition of Ocimum basilicum and evaluated their relationship with nitric oxide (NO) inhibitory activity and estragole exposure. Essential oils were obtained by hydrodistillation and analyzed by gas chromatography–tandem mass spectrometry (GC–MS/MS), resulting in the identification of 54 volatile compounds representing 98.13–98.97% of the total composition. Estragole remained the dominant constituent, ranging from 70.58% to 85.55%, with the lowest proportion at the flowering stage (Day 85). In contrast, minor constituents, including eucalyptol (2.41–3.77%), β-ocimene (0.52–1.98%), and methyleugenol (~2.00%), increased during flowering. NO inhibitory activity in lipopolysaccharide (LPS)-stimulated RAW 264.7 macrophages was strongest at Day 85. Estimated Daily Intake (EDI) ranged from 0.4215 to 1.1005 µg kg⁻¹ bw day⁻¹, and Margin of Exposure (MOE) ranged from 2999 to 7830. These findings indicate that developmental stage influences composition, activity, and exposure. From a compositional perspective, the observed redistribution among major chemical groups reflects a structured balance that can be interpreted within a symmetry-related framework in multicomponent systems. Full article

Growing interest in environmentally compatible stored-product pest control has highlighted diatomaceous earth (DE) and 1,8-cineole as promising agents, both alone and in combination. Their different modes of action, together with the limitations associated with higher-dose single applications, support evaluating their combined use at lower doses. This study was conducted to compare the effects of DE and 1,8-cineole, applied alone and in combination, on the larval, pupal, and adult stages of Tenebrio molitor. Five different concentrations were tested for each substance (DE at 25, 50, 100, 250, and 500 ppm, and 1,8-cineole at 2.5, 5, 10, 15, and 20 ppm), and four DE + 1,8-cineole combinations were evaluated within the same experimental system. Mortality was monitored over time, LC₅₀ values were calculated by probit analysis, and larval output observed after adult treatments was also evaluated. The findings indicated that the biological response was associated with developmental stage. The lowest LC₅₀ for DE was recorded in larvae at 86.11 ppm on day 3, whereas for 1,8-cineole the lowest LC₅₀ was recorded in adults at 94.83 ppm on day 3. Combined treatments generally tended to produce faster and stronger mortality; in particular, the DE250 + CIN20 treatment reached 100% mortality in larvae and adults and 93.33% mortality in pupae by day 7. In addition, larval output decreased in the single-treatment groups, the proportion of dead larvae among the observed larvae increased to 96–100%, and no larval output was detected in the combination groups. Combinations of DE and 1,8-cineole tended to produce more pronounced mortality responses than the single treatments, particularly in the larval and adult stages. The present findings indicate that combining DE with 1,8-cineole may provide a promising stage-specific strategy for improving the control of T. molitor under laboratory conditions. Full article

Temperature is a major determinant of plant metabolic plasticity, yet its role in directing volatile and semi-volatile specialized metabolism in Ginkgo biloba remains poorly understood. In this study, we investigated how contrasting low- and high-temperature treatments reshape secondary metabolite contents in G. biloba microclones cultivated in vitro. Plants were exposed to cold (+3 °C) and heat (+30 °C) conditions, and their responses were analyzed using GC–MS profiling, anatomical measurements, chlorophyll fluorescence, and multivariate statistics. Cold treatment selectively increased the abundances of monoterpenes (13.22%) and sesquiterpenes (13.83%), with the strongest accumulation of caryophyllene, eucalyptol, and (1S)-camphor. In contrast, heat treatment reduced ester content to 3.73% and strongly enriched oxy-sesquiterpenes (46.50%) and lactone/ketone/spiroketone (29.54%) contents. The enhanced accumulation of isocalamendiol, isoshyobunone, cyclohexanone derivative, dehydroxy-isocalamendiol, and (+)-2-bornanone was observed under heat. According to the multivariate analysis, control plants were associated with traits reflecting optimal physiological performance, including greater parenchyma, phloem, and xylem thickness, larger vascular bundles, longer stomata, and higher NPQ, qN, Y(NPQ), and F_v/F_m. Cold-treated plants showed thicker epidermis and sclerenchyma, higher stomatal density and width, elevated Y(NO), and an enrichment of esters and terpenoids, whereas heat-treated plants were characterized by thicker adaxial and abaxial epidermis, increased mesophyll thickness, and higher levels of oxygenated metabolites. These findings expand current knowledge beyond terpene trilactones and flavonoids and identify Ginkgo microclones as a useful in vitro model for temperature-guided metabolic reprogramming and targeted metabolite enrichment. Full article

In this study, we investigated the chemical composition, antimicrobial and antibiofilm activities, and cytotoxicity of Thuja occidentalis L. (thuja) and Myrtus communis L. (myrtle) essential oils (EOs) to evaluate their potential as natural alternatives for topical applications. Thuja EOs were extracted from fresh and dried leaves and cones, while myrtle EO was extracted from fresh leaves. GC-MS analysis revealed that myrtle EO was rich in oxygenated monoterpenes (58.2%), predominantly eucalyptol (41.86%) and α-pinene (20.98%). In contrast, thuja EOs were dominated by monoterpene hydrocarbons (55–82%), with α-pinene as the major component (29–66%), and their composition varied markedly with plant organ and moisture state. Myrtle EO displayed the most potent and broad-spectrum antimicrobial activity, with MIC values as low as 3.096 µL/mL against Staphylococcus aureus and Escherichia coli, and effectively inhibited microbial adherence. Thuja EOs showed selective activity, particularly against Gram-positive bacteria and Candida parapsilosis, with EOs extracted from fresh leaves and cones exhibiting the lowest MICs (1.95–7.8 µL/mL). All EOs did not show cytotoxicity to human keratinocytes at concentrations ≤125 µg/mL and, when diluted to 0.05%, indicated excellent skin compatibility in human patch tests. This study suggests that myrtle and thuja EOs, particularly myrtle, are promising and safe natural antimicrobial agents for dermatological and cosmetic formulations. Full article

Background: Plant-derived essential oils possess valuable bioactivities, but their application is limited by volatility and irritation, which may be addressed through natural polymer encapsulation. This study aimed to investigate the bioactivity of Hedychium coronarium rhizome essential oil and evaluate the effect of microencapsulation on its physicochemical characteristics, biological stability, and irritation profile. Methods: Essential oil was extracted from H. coronarium rhizomes by hydrodistillation and chemically characterized. Enzyme inhibitory activities against elastase, hyaluronidase, and tyrosinase were assessed. Microencapsulation was performed using gum Arabic or maltodextrin at 1–5% w/w oil loadings. The resulting powders were evaluated for morphology, entrapment efficiency, hygroscopicity, water activity, biological stability, and irritation potential using the hen’s egg test on the chorioallantoic membrane. Results: The essential oil demonstrated strong enzyme inhibition, particularly against hyaluronidase (IC₅₀ = 0.1 ± 0.0 µg/mL), along with notable elastase and tyrosinase inhibition. Encapsulation significantly reduced irritation scores from 13.3 ± 1.4 for the free oil to 3.6–4.2 for encapsulated systems (p < 0.05). Gum Arabic produced rough, porous particles with lower hygroscopicity, while maltodextrin yielded smoother particles with lower water activity. Both encapsulated powders significantly enhanced biological stability compared with the ethanolic solution. Conclusions: Natural polymer-based microencapsulation effectively reduced the irritation potential and improved the handling properties of H. coronarium essential oil, supporting its potential application in topical bioactive delivery systems. Full article

Background/Objectives: Microbial infections represent a major challenge in the food processing chain. Postharvest fungal control has historically relied on chemical control; however, their use is increasingly restricted due to environmental and health risks. Therefore, the aim of this study was to evaluate the antifungal potential of essential oils obtained from high-yield plant species and characterize the potential mechanisms of action of their major volatiles, with the goal of proposing a prospective formulation for the control of postharvest fungi. Methods: Cinnamon, rosemary, allspice, and Peruvian pepper essential oils were extracted by hydrodistillation, tested against Botrytis cinerea and Colletotrichum sp., and analyzed by gas chromatography-mass spectrometry. Finally, in silico bioactivity analyses were performed on the most abundant volatiles. Results: Cinnamon and rosemary produced the most effective oils against both fungal species. Cinnamaldehyde, cinnamyl acetate, eugenol, methyleugenol, (+)-2-bornanone, eucalyptol, α-phellandrene, and β-myrcene were some of the most abundant volatiles in the analyzed oils. In silico analyses predicted 56 antifungal mechanisms, including inhibition of cell membrane and wall synthesis, affectation of primary metabolism, inhibition of molecular processes, redox homeostasis, and protein degradation and cutinase inhibition. The last one is a specific mechanism mediating in vivo plant-fungal interactions found exclusively in β-terpinene and β-ocimene. Conclusions: Compounds with cutinase inhibition activity such as β-terpinene and β-ocimene are of great potential to complement the activity of other bioactive compounds. According to literature and in silico analyses the mixture of cinnamaldehyde, eugenol, β-terpinene and β-ocimene could be a potential formulation for the management of postharvest fungi. Full article

The genus Oncosiphon (Asteraceae), consisting of aromatic herbs, is indigenous to southern Africa. Oncosiphon species have been documented in Khoi-San ethnobotany as herbal remedies for typhoid fever, pneumonia, and as diuretics. Research on the biological properties and comprehensive phytochemical profiling of these important Oncosiphon species is currently limited. This study was therefore undertaken to address the knowledge void in chemical profiling, through the application of various analytical techniques to analyse the volatile and non-volatile constituents of three South African Oncosiphon species. The aerial parts of Oncosiphon suffruticosus (n = 28), O. grandiflorus (n = 16), and O. africanus (n = 4) were collected from various locations in the Western Cape Province of South Africa. The stems and leaves (SL) were separated from the flowers (F) and analysed as distinct samples. The methanol: chloroform (1:1, v/v) extracts were prepared and analysed using ultra–high–performance liquid chromatography quadrupole time-of-flight time–of–flight mass spectrometry (UHPLC–QToF–MS) and a semi–automated high–performance thin–layer chromatography (HPTLC) system. Multivariate data analysis was performed on the UHPLC–QToF–MS data to determine interspecies chemical variation. Two-dimensional (2D) gas chromatography (GCxGC–ToF–MS) was used to determine the headspace volatile profiles of the intact aerial parts. The results show that the non-volatile profiles of the Oncosiphon species are characterised by amino acids, phenolic acids, flavonoids, sesquiterpene lactones, and fatty acid derivatives. The HPTLC profiles of O. grandiflorus and O. africanus are chemically more closely related, and O. suffruticosus has a distinct profile, which is supported by the chemometrics results of the flowers. The major headspace volatile compounds in Oncosiphon flowers are α-pinene, α-ocimene, eucalyptol, o-cymene, and artemisia alcohol, whereas the stems and leaves mainly consist of α-ocimene, eucalyptol, and yomogi alcohol. Full article

Ceylon cinnamon (Cinnamomum verum J. Presl) bark essential oil (CBO) represents a promising source of natural bioactive compounds for biological plant protection. For the first time, the antibacterial and antifungal activity of CBO was systematically evaluated against a curated panel of phytopathogenic strains (IOR collection), revealing broad-spectrum efficacy across both bacteria and filamentous pathogens. This study evaluated its chemical composition, antimicrobial activity against phytopathogens, effects on bacterial metabolic activity, and its ability to induce plant defence responses. CBO was dominated by cinnamaldehyde, linalool, and eucalyptol. The oil exhibited strong antibacterial activity against Dickeya dadantii, Pectobacterium carotovorum, Pseudomonas syringae, and Xanthomonas hortorum as well as antifungal activity against Fusarium graminearum, F. culmorum, Rhizoctonia solani and Phytophthora cinnamomi. Metabolic assays revealed a marked reduction in bacterial metabolic activity, indicating that CBO disrupts physiological processes and inhibits growth. In planta experiments showed that foliar application of CBO stimulated PAL activity in wheat leaves without visible phytotoxic symptoms. These findings demonstrate a multifunctional mode of action of CBO, combining direct antimicrobial effects with the elicitation of plant defence responses, and support its potential application in sustainable crop protection. Full article

Seasonal variation is recognized as a key factor affecting the essential oil (EO) yield, chemical composition, and antioxidant activity of Laurus nobilis L. from the Montenegro coast, which constituted the focus of this research. The bay essential oil (BEO) yield was higher in summer (2.12%) and autumn (2.03%) than in winter (1.26%) and spring (1.28%). The total number of BEO components, depending on seasonal variability, ranges from 31 (summer) to 34 (winter and spring). 1,8-cineole (eucalyptol) was the major aromatic compound in all seasons, with the highest content recorded in summer (52.4%). Linalool, as the second most abundant component, is present in the autumn harvest (14.1%), while α-terpinyl acetate, as the third most abundant component, is most prevalent in the winter–spring period (9.6–9.7%). Two groups of monoterpenes, namely the oxygen-containing monoterpene derivatives (80.1%), constitute the most abundant components in BEO leaves, as well as monoterpene hydrocarbons (14.3–15.5%). The phenylpropanoids were the least abundant (4.9–6.3%). Stronger antioxidant activity (DPPH) during an incubation time of 20 min was shown by the BEOs isolated from autumn (EC50 value of 1.15 mg/mL). Early autumn (September) represents the optimal harvest time for L. nobilis in Montenegro, as they ensure a high essential oil yield and better quality, reflected in a high 1,8-cineole content and stronger antioxidant activity of the oil. These results demonstrate that seasonal variations are key factors regulating the quantity and quality of BEO, providing important information for optimizing harvest strategies for medicinal and industrial purposes. 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

Chimonanthus salicifolius and Chimonanthus nitens are widely used in the food and pharmaceutical industries. Traditionally, their stems and leaves have been consumed as herbal tea substitutes in folk practices, possessing both medicinal and edible values. They represent typical dual-purpose plants for both medicinal and tea applications and are distinctive ethnic She medicinal resources. This study used the flowers, stems, and leaves of C. salicifolius and C. nitens as materials to analyze the chemical components of six essential oils and evaluate their antioxidant and antibacterial activities. We extracted their essential oils through steam distillation, followed by an analysis of their volatile chemical components using gas chromatography–mass spectrometry (GC-MS). Hydroxyl radical (•OH), 1,1-diphenyl-2-picryl hydrazyl (DPPH) and the ferric reducing ability of plasma (FRAP) were used to evaluate the antioxidant activities of the different essential oils. The results showed that the extraction rates of both Chimonanthus species followed the order of leaf > flower > stem. Among them, the essential oil extraction rate from the leaves of C. salicifolius was the highest (2.22%), followed by that from the leaves of C. nitens (0.84%). A total of 83 volatile components were identified from the six extracted essential oils, demonstrating significant compositional differences (p < 0.05). Eucalyptol is the main component and has the highest relative content in the essential oils of both plant leaves, with (54.65 ± 1.03%) in C. salicifolius and (52.28 ± 1.03%) in C. nitens. Antioxidant experiments revealed that the leaf essential oil exhibited the strongest •OH scavenging activity (IC50 = 39.47 ± 5.57 μL·mL⁻¹), while the stem of C. salicifolius showed the highest DPPH scavenging activity (IC50 = 20.78 ± 3.86), and the flower part demonstrated the best FRAP power. Additionally, a preliminary evaluation of the antibacterial activity of these two Chimonanthus leaf essential oils indicated that their minimum inhibitory concentration (MIC) against Staphylococcus aureus, Bacillus pumilus, and Bacillus subtilis was consistently 50 µL·mL⁻¹. This study systematically analyzed the chemical composition, antioxidant activity, and antibacterial activity of essential oils from different parts of C. salicifolius and C. nitens, revealing differences in yield, component composition, and biological activity between the two species. The findings provide scientific evidence for the development and application of essential oils from Chimonanthus plants. Full article

Nowadays, there is a global trend of consuming lower-alcohol beverages, while there is a market trend for consuming ready-to-drink products. The present study describes the development of new alcoholic beverages by the simple addition of rose water to the traditional marc spirit tsipouro. New beverages have lower alcohol content (30% v/v) than the mother tsipouro (40% v/v), exhibiting noteworthy antioxidant activity. Tsipouro–rose water beverages exhibited several aroma volatiles which originated from rose water, as determined by SPME GC-MS. Among them were the phenylethyl alcohol, eucalyptol, linalool, citronellol, geraniol, alpha-terpineol, which are known as rose water aroma compounds. The antioxidant activity of tsipouro–rose water beverages as estimated by the Folin, FRAP and DPPH assays appeared to be higher than the diluted tsipouro of the same alcohol content in a dose-dependent manner after mixing and after storage for 30 and 60 days. Preliminary organoleptic evaluation indicated that tsipouro–rose water products exhibit a rose-like aroma and were of acceptable organoleptic quality, especially that with a lower concentration of rose water. Full article

Helichrysum Mill. is one of the largest genera in the Asteraceae family, and in Madagascar, a plant paradise with ca 14,000 species, 111 Helichrysum species are known, 110 of which are endemic. In this work, the essential oil of endemic Helichrysum manopappoides Humbert, obtained by steam distillation, was investigated chemically and biologically. The spectrometric data obtained by GC-MS (Gas Chromatography–Mass Spectrometry) analysis highlighted the presence of three major compounds, such as eucalyptol (7.38 ± 0.36%), α-humulene (14.75 ± 0.79%), and β-caryophyllene (19.78 ± 0.89%), which were also structurally confirmed by NMR (Nuclear Magnetic Resonance) spectroscopic investigation. Biological results showed potential antimicrobial, antioxidant, and antibiofilm effects of both the H manopappoides essential oil and the main components identified by GC-MS, enhancing an interesting approach for intestinal infections, being active against Escherichia coli, Listeria monocytogenes, Shigella sonnei, and Salmonella enterica ser. typhimurium strains. Full article

Antimicrobial resistance is a major global health concern, intensified by the misuse of antibiotics and the lack of new effective treatments. Bacteria capable of forming biofilms exhibit increased resistance, making infections more difficult to treat. This study evaluated the essential oil from Croton pluriglandulosus leaves (OCp) for its antibacterial and antibiofilm properties. The essential oil, obtained by hydrodistillation and analyzed by GC-MS, contained eucalyptol (24.11%), spathulenol (16.90%), α-pinene (11.76%), and caryophyllene oxide (10.07%) as main constituents. Antibacterial activity was determined by Minimum Inhibitory Concentration (MIC) and Minimum Bactericidal Concentration (MBC), with inhibition observed only for Staphylococcus aureus (MIC 10 mg/mL; MBC 5 mg/mL). OCp reduced biofilm biomass and CFUs in most strains, particularly in S. aureus and Escherichia coli. Scanning Electron Microscopy (SEM) and Confocal Laser Scanning Microscopy (CLSM) showed membrane damage in treated cells. Overall, OCp displayed promising antibacterial and antibiofilm potential, representing the first report of such activity for this essential oil. Full article