Search Results (175)

Multidrug-resistant Acinetobacter baumannii isolates pose a threat to healthcare systems worldwide. The antibacterial activity of essential oil components (EOCs)—linalool, geraniol, eugenol, citronellol, 1,8-cineole, carvacrol, and trans-anethole—was evaluated both alone and in combinations against multidrug-resistant A. baumannii clinical strains from wound infections, and against two reference strains. The minimum inhibitory concentrations (MICs) and minimum bactericidal concentrations (MBCs) of EOCs were determined using the broth microdilution method. The interactions between EOCs were investigated using the checkerboard microdilution method. Carvacrol and eugenol showed the strongest inhibitory effects against the tested strains. The MICs and MBCs of carvacrol were 1.70–3.39 mg/mL. The MICs of eugenol were 4.10–16.41 mg/mL, while the MBCs were 4.10–32.81 mg/mL. MIC/MBC analysis showed that all tested EOCs had bactericidal activity against A. baumannii in vitro; however, some required higher concentrations. Most EOC mixtures showed synergistic interactions. The combination of eugenol and carvacrol induced the strongest synergistic effect, leading to the greatest reduction in the MICs of both compounds (MIC of carvacrol decreased by 8–30-fold, while the MIC of eugenol decreased by 16–64-fold). Our results indicate that some EOCs, especially when combined, exhibit significant antibacterial activity against A. baumannii. Full article

This study evaluated the physiological and production responses of broilers to a phytogenic nutritional additive (PNA) applied under different dietary nutrient matrix credit strategies. The PNA contained star anise essential oil, thyme essential oil, and Quillaja saponaria Molina stem and leaf powder, with trans-anethole, p-cymene, and thymol as the main characterized marker compounds. A total of 384 one-day-old male Arbor Acres broilers were assigned to four treatments (eight replicates of 12 birds): a basal control diet without PNA (CON) and PNA-supplemented diets using full matrix credit (PNA-FM), protein matrix credit (PNA-PM), or no matrix credit (PNA-NM). Growth performance was unaffected (p > 0.05), whereas all PNA-supplemented groups had higher dressed percentages and eviscerated yields than CON (p < 0.01). PNA-PM and PNA-NM increased the muscle pH (p < 0.01), and PNA-NM increased drip loss and shear force (p < 0.05). Intestinal responses were time-dependent: on day 14, PNA-NM increased serum FITC-d, tended to increase DAO activity, and downregulated ZO-1 expression, while all PNA-containing treatments reduced the villus height and villus height-to-crypt depth ratio (p < 0.01), suggesting a transient epithelial adjustment rather than direct barrier improvement. On day 22, qualitative TEM observations suggested closer epithelial junctions in PNA-containing treatments. These results indicate that PNA-containing formulation strategies did not compromise growth performance and modified carcass traits, meat quality traits, intestinal responses, and the excreta nutrient composition. Because PNA-free full matrix and protein matrix control diets were not included, these findings should be interpreted as responses to complete dietary strategies rather than as formal PNA × nutrient matrix interactions. Full article

Foeniculum vulgare Mill. (fennel) is an edible and medicinal plant cultivated worldwide. Owing to its distinctive aroma and diverse biological activities, its essential oils (EOs) have been widely investigated. However, available data predominantly focus on cultivated fennel or commercial EOs, while comprehensive investigations of wild-growing Mediterranean populations—particularly comparisons among different plant parts—remain scarce. In this study, EOs obtained by hydrodistillation from stems, leaves, flowers, and fruits of native Croatian fennel, were chemically characterised using gas chromatography-mass spectrometry (GC-MS), while antimicrobial activity was evaluated using the disc diffusion method against four bacterial strains. Additionally, the volatile profiles of fennel hydrolates were determined by headspace solid-phase microextraction (HS-SPME) and GC-MS analysis. Fennel flowers gave the highest EO yield (1.95%), followed by mature fruits (1.43%), whereas significantly lower yields were obtained from leaves (0.69%) and stems (0.58%). Trans-anethole was identified as the dominant constituent (from 40.96% in stems to 80.71% in fruits), while α-phellandrene predominated in stem EO (42.77%). Hydrolate volatile profiles were more complex—particularly leaf hydrolate, where 29 compounds were identified. The principal constituents were trans-anethole (39.58–57.40%) and fenchone (16.01–28.80%), while the highest content of estragole was observed in fruit hydrolate (6.56%). The EOs demonstrated moderate antimicrobial activity, showing effectiveness exclusively against Escherichia coli, likely attributable to high phenylpropanoid (primarily trans-anethole) and fenchone contents. Full article

Feed additives based on essential oils (EOs) have emerged as a potential alternative to ionophores for diets with elevated grain inclusion. Also, on some occasions, EOs have been used in combination with monensin, with variable results. A metabolism trial was conducted using a 2 × 2 factorial arrangement of treatments, evaluating supplementation with (A) monensin sodium (0 mg/steer daily vs. 400 mg. steer daily) and (B) a blend of EOs (eugenol, linalool, anethole, and cinnamaldehyde, 0 g/d vs. 14 g/d). Four Red Angus steers (BW = 435 ± 9.0 kg) with ruminal and duodenal cannulas were used, and the study was conducted as a Latin square with four periods of 28 days each. Ruminal fermentation and nutrient digestibility at different levels (ruminal, intestinal, and total tract) were determined. The EOs increased total tract starch digestibility (p = 0.05) by 4.5% and propionate concentration (p = 0.03) by 30.9%. Furthermore, EOs decreased acetate (p = 0.04) by 7.4% as well as the acetate to propionate ratio (p = 0.03). In conclusion, our results suggest that it is safe to combine this EO blend with monensin for feedlot diets. The EO blend improved starch digestibility and increased efficiency of the ruminal fermentation end-products, which suggests it could be beneficial in diets based upon grain. Full article

The geographical origin of aniseed (Pimpinella anisum L.) represents a key quality determinant, as it directly influences the chemical composition and commercial value of its essential oil. Agronomic traits of aniseed (plant height, umbel diameter, number of umbels per plant), productivity-related traits (number of seeds, thousand-seed weight, yield per plant, plant biomass, harvest index, yield per hectare, essential oil content and yield), and physiological traits (germination energy and total germination) exhibit variations depending on geographical origin. The study proposes an integrated framework for accurate classification by combining agronomic, productivity, and physiological data with GC-MS profiles and advanced machine learning (ML) techniques. A total of 144 samples were analyzed, based on a factorial design including three locations, six fertilizer treatments, two years, and four replications. trans-Anethole was the dominant compound in all samples (89.508–101.441%). Several classification models, including artificial neural networks, random forests, MARSplines, boosted trees, interactive trees, naïve Bayes, and support vector machines, were evaluated to discriminate samples by geographical origin using agro-meteorological and GC-MS data. The results indicate that AI and ML approaches effectively captured complex non-linear relationships. Overall, the multi-model framework highlights the strong potential of machine learning for agro-food authentication, supporting improved traceability, site-specific decision-making, and quality control. Full article

Trans-anethole oxygenase (TAO) exhibits broad arylpropene substrate specificity but has low activity in converting isoeugenol to high-value vanillin. Herein, we employed computer-aided rational design to engineer TAO from Pseudomonas putida (PpTAO) for enhanced catalytic efficiency toward isoeugenol. Structural modeling and AlphaFold 3 docking identified two key catalytic residues, Arg86 and His118. Through substrate channel engineering and computation-guided mutagenesis, a series of targeted variants were constructed. Three variants, H93A, Q207R/G249C, and I59T/F62T, showed significant improvements in whole-cell performance, with activity increases of 1.8-, 2.13-, and 4.83-fold over the wild type (WT), respectively. Purified enzyme kinetics corroborated these findings, as reflected in k_cat/K_m values that reached 1.6, 2.1, and 4.7 times that of the WT. Mechanistic molecular dynamics simulations revealed that H93A enhances activity by widening the access tunnel, whereas Q207R/G249C exerts beneficial distal effects. Notably, the I59T/F62T variant significantly increases substrate affinity by optimizing hydrophobic interactions within the binding pocket. These results validate the efficacy of computational modeling in enzyme redesign and provide a robust biocatalyst for the sustainable biosynthesis of vanillin. Full article

Rakı, a traditional distilled beverage produced from grapes, holds significant economic importance in Türkiye; however, comprehensive consumer-focused sensory research remains limited. This study aims to determine the aroma profile, sensory characteristics, and consumer preferences of commercial rakı to guide producers in aligning product characteristics with consumer expectations. Nine commercial rakı samples were evaluated. The aroma composition was analyzed using SBSE-GC-MS. Sensory attributes were assessed by a trained panel through descriptive analysis (DA) and by 100 consumers utilizing the Check-All-That-Apply (CATA) method alongside a liking test. Eighty-one aroma compounds were identified, predominantly the phenylpropanoids trans-anethole and estragole, with monoterpenes and sesquiterpenes dominating the secondary profile. Integrating instrumental data with DA evaluations suggests that anethole and sesquiterpenes likely contribute to the attributes related to visual coating, body, creamy, mastic, persistency, and complexity. Consumer profiling revealed two distinct preference groups. Older, frequent consumers preferred complex, high-alcohol profiles with trigeminal harshness and visual glass coating, whereas younger, casual consumers preferred smoother rakı with a traditional white appearance, reacting negatively to “boiled aniseed” flavors and the yellowish tint of oak-aged versions. The CATA technique effectively distinguished these profiles. To enhance overall product quality, producers should eliminate “boiled” defects and adjust sensory profiles: complex products for experienced consumers and visually traditional, smooth profiles for younger consumers. According to current knowledge, this is the first study to employ the CATA method alongside consumer profiling and preference mapping in the sensory evaluation of rakı. Full article

Botanical insecticides containing a mixture of plant essential oils (EOs) are considered suitable for the management of houseflies (M. domestica). The adulticidal efficacies of single EOs and mixtures of EOs, including lemongrass (C. citratus), star anise (I. verum), nutmeg (M. fragrans), and their components (geranial, trans-anethole, and α-pinene), against houseflies were determined in comparison to 2% (w/v) α-cypermethrin as the positive control and distilled water as the negative control. The mixture of star anise EO (1%) + geranial (1%) was the most effective adulticide, superseding single EOs, other combinations of EOs, and its active component, α-cypermethrin, and distilled water. This mixture was highly synergistic and was found to be over 74% more toxic than all single EOs and almost 2.6 times more toxic than α-cypermethrin. Furthermore, the tested EOs did not cause mortality in guppies (P. reticulata) or earthworms (E. fetida), and caused a maximum of 48% mortality in honeybees (A. mellifera) at 24 h; by contrast, α-cypermethrin led to 100% mortality in honeybees within 0.5 h and in guppies and earthworms within 24 h, although it had low toxicity toward houseflies. Thus, a mixture of star anise EO + geranial is a promising source of EO-derived insecticides for housefly control that is also safe for important non-target species. Full article

The aim of this study was to evaluate the bioactive compounds and antioxidant activity of lemon balm (Melissa officinalis L.) grown under two farming systems (conventional vs. organic farming). From the content of photosynthetic pigments, total phenolics, and total flavonoids, as well as individual phenolic acids and flavonoids, the antioxidant potential was evaluated in 95% and 50% ethanol extracts. Moreover, GC-MS analysis of lemon balm essential oils was used to reveal the detailed composition. Forty-three compounds were detected in the essential oil from organic farming lemon balm, representing 99.70% of the total content. Among these, several compounds, such as α-pinene, n-octan-3-ol, bergamal, trans-rose oxide, dihydro-linalool, cis-isocitral, and trans-anethole, were found exclusively in the organic essential oil. In comparison, thirty-six compounds were detected in the essential oil from conventionally grown plants, representing 99.80% of the total content. The organically grown lemon balm demonstrated higher values of phenolics, flavonoids and antioxidant activity in comparison to the conventional ones. The levels of natural pigment were more than twice as high in the conventionally grown samples. Moreover, the 50% ethanol extracts contained 1.5 to 2 times more phenolic compounds with the highest antioxidant potential by the CUPRAC method. A positive linear correlation (r² = 0.98) was found between total phenolics and electron transfer-based antioxidant methods. Therefore, the organic farming led to the production of lemon balm with more secondary metabolites, such as phenolic acids and flavonoids, with higher antioxidant activity. Full article

In order to find green fungicides derived from natural products, 22 unreported anethole-based thiazolinone-hydrazone compounds were designed and synthesized, and their structures were characterized by FT-IR, ¹H NMR, ¹³C NMR, and HRMS. At a concentration of 50 mg/L, the preliminary antifungal activity of the target compounds against eight plant pathogens was evaluated. The results showed that 5q (R = m-OH C₆H₄) exhibited the best inhibitory activity against most of the tested plant pathogenic fungi, demonstrating that this compound had certain broad-spectrum antifungal activity. In addition, a reasonable and effective 3D-QSAR model (r² = 0.994, q² = 0.529) was established using the comparative molecular field analysis (CoMFA) method to study the relationship between the structures of the target compounds and their antifungal activity against Physalospora piricola. Meanwhile, the results of electrostatic potential calculation of the compounds indicated that the electronic effect caused by different substituents on the benzene ring might be one of the factors affecting antifungal activity. In addition, frontier molecular orbital calculations implied that the anethole moiety and the thiazolinone-hydrazone-benzene structure in the target compounds might play an important role in antifungal activity. The potential binding mode between the target compound 5q (R = m-OH C₆H₄) and the homology-modeled succinic dehydrogenase was explored by molecular docking. Full article

The hydroformylation of alkenylbenzenes remains insufficiently defined, despite the relevance of these substrates as biomass-derived aromatic feedstocks within sustainable chemical transformations. In this work, we present an experimental (catalytic and kinetic) study of their conversion into aldehydes under rhodium-phosphine catalysis, using complexes bearing mono-, bi- and tridentate phosphine ligands, [Rh(H)(CO)₂(PPh₃)₂], [Rh(H)(CO)(triphos)] and [Rh(H)(CO)₂(dppe)], under mild reaction conditions (80 °C and 2–30 bar of syngas for eugenol; 80 °C and 20–50 bar of syngas for estragole and trans-anethole). The catalytic activity order of the complexes was Rh (PPh₃) > Rh(triphos) > Rh(dppe), while the substrate reactivity followed the trend eugenol > estragole >> trans-anethole. Reaction rates were measured across a wide CO and H₂ pressure range, revealing redistribution between the active monocarbonyl species and an off-cycle (acyl)dicarbonyl complex that becomes dominant at elevated p(CO). The kinetic behavior observed for eugenol hydroformylation with Rh(PPh₃) was consistent with the established hydroformylation sequence involving alkene coordination, hydride migration to substrate and the CO-dependent re-coordination steps that determine catalyst speciation; the subsequent transfer of the alkyl group to the carbonyl ligand and hydrogenolysis complete the catalytic cycle; the H₂ addition or the hydride transfer to the alkene was identified as the rate-determining step, depending on whether low or high p(H₂) values were employed. To obtain statistically reliable kinetic parameters- often challenging in hydroformylation because of parameter covariance and restricted identifiability- we complemented conventional nonlinear regression with Bayesian inference based on the Markov Chain Monte Carlo approach. The resulting posterior distributions were well centered, exhibited realistic variance and provided parameter sets that are sufficiently robust to support mechanistic interpretation and subsequent kinetic modeling. Full article

Tartary buckwheat (Fagopyrum tataricum), a medicinal and edible crop, is valued for its richness in flavonoids and polyphenols, which confer antioxidant and hypoglycemic activities. Eurotium cristatum, a dominant fungus crucial for the quality of Fuzhuan tea, produces unique aromas and metabolites. This study developed cookies by replacing 20% of low-gluten flour with Tartary buckwheat flour that had undergone solid-state fermentation with E. cristatum followed by baking. Compared to cookies containing non-inoculated buckwheat flour, the fermented cookies contained significantly higher levels of total flavonoids (4.97 mg/g) and polyphenols (2.31 mg/g), and exhibited markedly enhanced antioxidant activity, as evidenced by a 16.4% higher ABTS radical scavenging rate and a 42.5% greater ferric reducing power. The fermented cookies also exhibited improved textural and sensory properties, a unique aroma profile characterized by pleasant floral notes, and a more homogeneous microstructure. HS-SPME-GC-MS analysis indicated that the optimized flavor resulted from the upregulation of key pleasant aroma compounds (e.g., (E)-2-nonenal, anethole) and the suppression of specific off-odor compounds (e.g., 2-ethyl-3,5-dimethylpyrazine, p-cresol). In conclusion, solid-state fermentation with E. cristatum followed by baking, effectively improves both the nutritional and sensory characteristics of Tartary buckwheat cookies, providing a viable strategy for developing novel, health-promoting bakery products with an appealing compelling flavor profile. Full article

Essential oils (EOs) have emerged as promising natural antimicrobials for food safety applications. However, their direct use on food-contact surfaces—such as wood and plastic, commonly employed in artisanal cheese production—has been scarcely explored. This study aimed to evaluate the antibacterial effects of dill (Anethum graveolens) and nettle (Urtica dioica) essential oils against Listeria monocytogenes and Escherichia coli, both in culture media and on inert surfaces. EOs were extracted via steam distillation and characterized by gas chromatography–mass spectrometry (GC-MS). Antimicrobial activity was assessed using agar diffusion and minimum inhibitory concentration (MIC) assays. In addition, bacterial reduction was quantified following EO application to contaminated wooden and plastic surfaces for 40 min. Dill EO exhibited a high anethole content (63.66%), while nettle EO was dominated by limonene (38.73%). Dill EO produced larger inhibition zones against E. coli (13.7 ± 1.5 mm) and L. monocytogenes (12.3 ± 1.5 mm) compared to nettle EO (6.3 ± 0.6 mm and 8.0 ± 1.7 mm, respectively). On plastic, both EOs achieved complete inhibition of E. coli (100%) and greater than 92% reduction in L. monocytogenes. On wood, dill EO maintained high efficacy (up to 87.9%), whereas nettle EO showed limited reduction (29.3%) against L. monocytogenes. These results demonstrate that EO efficacy is influenced by both surface type and target microorganism, supporting the potential of dill EO as a natural antimicrobial agent for surface sanitation in artisanal cheese production. Full article

Anise (Pimpinella anisum L.) is one of the most important annual herbs of the Apiaceae family, widely cultivated in southern Spain. Their seeds are highly valued for culinary uses and for producing quality essential oils widely used in food and beverage products, as well as for industry, medicinal, and cosmetics applications. This study investigates the seed yield and essential oil content within a set of 50 anise accessions from worldwide origin, as well as their composition by GC–MS and GC–FID analysis. Accessions showed significant differences in the agronomic parameters measured, including plant height (cm), seed yield (kg ha⁻¹), and the Harvest Index (%), with accessions PA_87 (Spain), PA_47 (Greece), and PA_21 (unknown origin) being the most performant. Essential oil (EO) content varied between 0.8% and 5.7% across different genotypes, resulting in EO production values ranging from 0.1 to 300 kg ha⁻¹. Trans-anethole was identified as the dominant terpene, comprising 84.4% to 94.4% of the content, followed by eugenol (1.4% to 5.5%) and α-muurolene (1.4% to 7.2%). PCA analysis identified five distinct groups and one outlier, influenced by minor terpenes. Indeed, there was a strong negative correlation between estragole and pseudoisoeugenyl 2-methylbutyrate. This study underscores the significance of minor terpenes, which play crucial roles in defining unique aniseed chemotypes, allowing for the selection of cultivars optimized for specific uses in food, cosmetics, and pharmaceuticals. Additionally, these findings emphasize the impact of cultivar genetics on agronomic traits and EO profiles, suggesting the need for further research to optimize plant growth and yield and EO quality. Full article

This study develops a comprehensive workflow integrating Headspace Solid-Phase Microextraction Gas Chromatography–Mass Spectrometry (HS-SPME-GC-MS) with advanced supervised machine learning to authenticate the botanical origin of honeys from five distinct floral sources—coriander, orange blossom, astragalus, rosemary, and chehelgiah. While HS-SPME-GC-MS combined with traditional chemometrics (e.g., PCA, LDA, OPLS-DA) is well-established for honey discrimination, the application and direct comparison of Random Forest (RF), eXtreme Gradient Boosting (XGBoost), and Neural Network (NN) models represent a significant advancement in multiclass prediction accuracy and model robustness. A total of 57 honey samples were analyzed to generate detailed volatile organic compound (VOC) profiles. Key chemotaxonomic markers were identified: anethole in coriander and chehelgiah, thymoquinone in astragalus, p-menth-8-en-1-ol in orange blossom, and dill ester (3,6-dimethyl-2,3,3a,4,5,7a-hexahydrobenzofuran) in rosemary. Principal component analysis (PCA) revealed clear separation across botanical classes (PC1: 49.8%; PC2: 22.6%). Three classification models—RF, XGBoost, and NN—were trained on standardized, stratified data. The NN model achieved the highest accuracy (90.32%), followed by XGBoost (86.69%) and RF (83.47%), with superior per-class F1-scores and near-perfect specificity (>0.95). Confusion matrices confirmed minimal misclassification, particularly in the NN model. This work establishes HS-SPME-GC-MS coupled with deep learning as a rapid, sensitive, and reliable tool for multiclass honey botanical authentication, offering strong potential for real-time quality control, fraud detection, and premium market certification. Full article