Search Results (1,253)

Background/Objectives: Teucrium polium L. is widely used in traditional medicine and has been proposed as a source of antimicrobial adjuvants in the context of antimicrobial resistance. Here, we characterized the essential oil (EO) and polar extracts of T. polium and evaluated their antioxidant activity, antimicrobial potency against clinical multidrug-resistant (MDR) isolates, and the interaction of the EO with conventional antibiotics using a chequerboard assay (FICI); further, we investigated in silico molecular interactions with some targets related to resistance. Methods/Results: The EO, which was hydrodistilled and subsequently analyzed by GC–MS, is characterized by dominant limonene content (24.13%) and contents of oxygenated sesquiterpenes such as β-eudesmol (10.48%) and α-muurolol (8.10%). HPLC/UV–ESI–MS characterization of the extracts (decoction and Soxhlet) demonstrated that they were rich in polyphenolic compounds and flavonoids, which matched the standard phytochemical characteristics of this species. The extracts exhibited significant reducing capabilities, and the hydroethanolic extract exhibited the highest antioxidant activity (DPPH IC₅₀ = 15.41 μg/mL; FRAP EC₅₀ = 30.65 μg /mL), while the EO revealed at most moderate capacity in these tests. In antimicrobial assays, the EO inhibited fungi more effectively than the extracts (MIC of 1.17 mg/mL against Aspergillus niger; 4.69 mg/mL against Candida spp.), while antibacterial MICs for both the EO and extracts were generally high (up to 50 mg/mL). Combination testing nevertheless identified synergistic or additive effects of the EO with selected antibiotics, notably with ceftazidime against ESBL-producing Escherichia coli (FICI = 0.141) and Staphylococcus aureus (FICI = 0.039) and with amikacin against Klebsiella pneumoniae (FICI = 0.313); the EO–ceftriaxone pairing against ESBL E. coli was additive (FICI = 0.516). Docking simulations further supported these observations by showing the favorable predicted binding of oxygenated sesquiterpenes, most notably β-eudesmol and α-muurolol (up to −8.6 kcal/mol), to resistance-related targets such as RND efflux pumps, β-lactamases, and porins. Conclusions: Taken together, the in vitro and in silico data suggest that T. polium could be explored as a natural antimicrobial option and as an adjuvant to enhance antibiotic activity against multidrug-resistant pathogens. Full article

This study evaluated the effects of essential oils, such as limonene (LIM) and a cinnamaldehyde–carvacrol blend (CCB), on the fermentation, chemical composition, in vitro digestibility, and aerobic stability of corn silage stored for 150 and 200 days. Treatments included a control, CCB (100 and 200 mg/kg DM), and LIM (100 and 200 mg/kg DM). Essential oils improved fermentation by increasing lactic acid (up to 7.46% of DM) and reducing proteolysis (NH₃-N: 0.46–0.59% of total N). Limonene, particularly at 100 mg/kg DM, enhanced the lactic:acetic acid ratio (up to 3.07), better preserved non-fiber carbohydrates (≈32.7%), and increased in vitro DM digestibility (up to 81.5%) compared to the control (≈76.0%). The CCB treatment raised acetic acid concentrations (up to 3.04% of DM). Extending storage to 200 days reduced DM recovery (≈84.0%) versus 150 days (92.5%). Treated silages showed greater aerobic stability, with a lower pH increase after 72 h of air exposure, most notably in the LIM 200 treatment (pH 4.10) compared to the control (pH 5.40). Essential oils, particularly limonene, effectively improve the fermentative quality, nutritional value, and aerobic stability of corn silage under prolonged storage. Full article

The maize weevil is a major postharvest pest of stored maize, causing substantial quantitative and qualitative grain losses and posing a serious threat to food security. In many regions of the world, particularly in developing countries where maize is a staple crop, maize weevil infestations can account for up to 50% of postharvest maize losses annually. Traditionally, synthetic pesticides have been used to manage maize weevils, but their prolonged application has been associated with environmental contamination, pesticide resistance, and adverse health effects in humans and animals. These challenges have inspired the search for safe, eco-friendly, and bioactive alternatives from natural sources. Citrus plants are among the most widely consumed fruits globally, with their peels and leaves constituting a significant proportion of agricultural waste. These waste products are rich in essential oils, particularly limonene, which has demonstrated potent insecticidal properties against maize weevils. Repurposing citrus waste into biopesticides offers a sustainable strategy for mitigating maize weevil infestations, thereby reducing postharvest maize losses and enhancing food safety and security. This review examines the prospects of citrus limonene in the development of safe and effective maize weevil biopesticides, highlighting its major chemical constituents, biological activities, and mechanisms of action. Full article

Technological solutions might be of great importance for reducing food waste. In the scope of this article, gas sensor systems for assessing the edibility of food have been studied, which can help to avoid food losses by suggesting consumption before spoilage or by separating infected fruits from fresh ones. Several series of measurements with various foodstuffs were conducted to develop methods that enable the identification of possible use cases in which gas sensors could be used to assess food condition as well as methods to calibrate such sensor systems. This paper presents results for oranges as an important target for grocery stores. The fruit headspace was measured by gas sensors, reference data were acquired using human assessment (appearance, odor, edibility) and gas chromatography–mass spectrometry (GC-MS) analysis. Data evaluation shows correlations between the performance of individual sensors for a technical assessment of fruit condition with marker substances identified by GC-MS, e.g., limonene for damaged oranges. Models were derived that are, in general, able to quantify the edibility or to classify defects/mold, but limitations in the applicability/transferability, e.g., between orange varieties, were also identified. With the knowledge gained, important steps could be taken towards an application-oriented setup, and recommendations regarding the sensors used, food trained, and calibration methods applied are derived. Full article

Lobesia botrana is a major pest in grapevine, monitored using sex pheromone as a standard practice. However, when the sex pheromone is used in mating disruption (MD), monitoring becomes ineffective. A blend of 2-phenylethanol (2-PET) and acetic acid (AA) was identified as an attractant for L. botrana in MD vineyards. With the aim of increasing the attraction of 2-PET/AA, we evaluated whether terpenoid-based attractants and trap color could enhance the catches of L. botrana in traps baited with 2-PET/AA. First, we assessed the attraction to 2-PET/AA in combination with two terpenoid mixtures. Grape Mimic Mixture 1 (GMM1) contained a 100:78:9 proportion of (E)-β-caryophyllene, (E)-4,8-dimethyl-1,3,7-nonatriene, and (E)-β-farnesene, and Grape Mimic Mixture 2 (GMM2) was composed of a 10:1:1:1:1:1 proportion of limonene, (E)-4,8-dimethyl-1,3,7-nonatriene, (±)-linalool, (E)-caryophyllene, farnesene, and methyl salicylate. Furthermore, we assessed whether traps of different colors (blue, green, orange, red, white, and transparent) could enhance L. botrana catches. Neither GMM1 nor GMM2 improved L. botrana catches over 2-PET/AA alone. In addition, the proportion of mated L. botrana females was similar across treatments. Transparent traps caught more moths than other colors. Our results suggest a modification in the color and odor of traps to improve the monitoring of L. botrana in vineyards treated with MD. Full article

Zanthoxylum planispinum var. dingtanensis (hereafter Z. planispinum) is a pioneer plant for the ecological restoration of karst rocky desertification, offering both ecological rehabilitation and economic benefits. Due to the combined pressure from soil degradation and fruit harvesting, nutrient depletion and quality decline have intensified. Therefore, investigating the effects of fertilization on pericarp yield and quality provides the scientific basis for its precise fertilization. This study examined a Z. planispinum plantation subjected to five treatments in 2021: no fertilization (CK); organic fertilizer + chemical fertilizer + sprinkler irrigation (T1); chemical fertilizer + sprinkler irrigation (T2); chemical fertilizer alone (T3); and legume (soybean) intercropping + chemical fertilizer + sprinkler irrigation (T4). It explored the intrinsic relationships between fruit quality and soil physicochemical properties, identified key soil factors, and conducted a comprehensive quality evaluation, providing a scientific basis for precise fertilization in karst regions. The results indicated that (1) whole-fruit water content ranged from 61.30% to 64.37%, showing no significant differences, while variations were observed in the other phenotypic traits. T1 exhibited the highest values for Hydroxy-β-sanshool (2.42 mg·g⁻¹), Hydroxy-ε-sanshool (0.80 mg·g⁻¹), essential oil content (8.57%), and fresh weight per plant (9.9 kg). After long-term soybean intercropping, pericarp thickness reached its maximum (0.45 mm), but the content of aroma compounds decreased significantly. Compared to the other four treatments, the unfertilized control (CK) showed significantly higher values for the pericarp dry weight ratio, proportion of closed-eye peppercorns, and relative content of d-limonene, with increases of 5.5–13.94%, 130.91–568.42%, and 8.74–14.46%, respectively. (2) An inhibitory effect was observed between pericarp numbing compounds and soil calcium/phosphorus levels, while the synthesis of aroma compounds was constrained by the soil C/N ratio. Soil P/K ratio was identified as the dominant factor affecting overall quality. (3) The comprehensive fruit quality index ranked as follows: T1 (1.2933) > T3 (0.666) > T2 (0.5285) > CK (−1.1555) > T4 (−1.2098). Therefore, the T1 treatment is recommended for promotion as the fertilization management practice for Z. planispinum plantations in karst regions. Full article

This review examines the implementation dimensions of integrated lemon biorefinery systems, including cascade valorisation design, circular-economy integration, life-cycle assessment, techno-economic feasibility, and regulatory frameworks. Bibliometric analysis of Web of Science data (2015–2025) reveals exponential growth in citrus-biorefinery research, with lemon representing a burgeoning subset. Techno-economic assessments indicate that cascade biorefineries recovering essential oils, pectin, polyphenols, nanocellulose, and bioenergy can achieve cumulative revenues of USD 400–650 per tonne of dry peel. Whilst small-scale units (<500 tonnes per year) struggle to achieve viability, industrial simulations demonstrate Internal Rates of Return exceeding 18% at processing scales above 100,000 tonnes annually (2025 basis). Life-cycle assessments confirm environmental benefits, with greenhouse gas reductions of 60–85% relative to conventional disposal. Critical success factors include adopting green extraction technologies to preserve bioactive integrity and mitigating D-limonene inhibition in downstream anaerobic digestion. These findings establish essential oil extraction and pectin recovery as commercially mature technologies, whilst integrated multi-product lemon biorefineries remain economically promising based on techno-economic modelling and pilot-scale demonstrations, provided regulatory hurdles are effectively navigated. Full article

Ripened Pu-erh tea (RPT) experiences notable aroma transformations during industrial pile fermentation, yet the stage-dependent evolution of key aroma compounds remains poorly understood. This study analyzed two independent industrial batches of RPT across three fermentation stages: raw material (RM), intermediate fermentation (IF), and final fermentation (FF). Using HS-SPME/GC-MS coupled with multivariate statistical analysis and relative odor activity values (rOAVs), 134 volatile organic compounds (VOCs) were identified, with hydrocarbons, alcohols, and esters as predominant classes. In total, 13 key aroma-active compounds (rOAVs > 1) were found to be major contributors to RPT’s characteristic aroma. During early fermentation, relative levels of VOCs responsible for fresh and green aromas (e.g., linalool, D-limonene) diminished, while those for woody and minty aromas (e.g., isophorone, methyl salicylate) increased. A flavor wheel was developed to illustrate the dynamic shifts in aroma profiles. This stage-resolved analysis offers new mechanistic insights into aroma formation, aiding in the optimization of aroma quality control and process standardization for RPT production. Full article

Heat stress (HS) poses a significant stress challenge to growing lambs, impacting growth performance, health, and physiological responses. The study evaluated feeding an essential oil blend (EOB) on growth performance, physiological and blood parameters, oxidative, and immune responses. Thirty-two 3 mo old female (BW 18.6 ± 2.43 kg) crossbred (Mongolian × Thin-tailed Han F1) lambs were randomly assigned to either: (1) control (CON)—grain mix without EOB; or (2) EOB—an EOB blend supplemented at 4 g/kg grain mix. The EOB blend was comprised of 4.34% Zanthoxylum, 1% capsicum, and 1.06% cinnamon oils with 93.6% attapulgite carrier containing linalool, sabinene, limonene, capsaicin, cinnamaldehyde and eugenol. Extreme heat stress occurred for 39 out of the 45 d experiment. Feeding HS lambs EOB increased (p < 0.05) ADG (107.4 and 162.0 g/d for CON and EOB, respectively), forage intake (239.2 and 287.0 g/d), DMI (863.1 and 930.2 g/d), and feed efficiency (0.123 and 0.181 ADG, g/DMI, g) compared with lambs fed CON. Feeding EOB reduced (p < 0.01) respiration rates (RR) and rectal (RT) and skin temperatures (ST) compared to CON-fed lambs. Lambs fed EOB had a higher T-SOD activity and IgM concentration (0.05 < p < 0.10) than CON-fed lambs. Growing heat-stressed lambs fed EOB demonstrated a lower (p < 0.05) eosinophil percentage. Feeding EOB ameliorated HS conditions for growing crossbred lambs, which demonstrate improved growth performance, enhanced physiological responses, and overall health status. Full article

This study presents the development and evaluation of surface functionalized solidly mounted resonators (SMRs), including custom developed at the University of Warwick (UWAR) devices and commercial Sorex sensors, for the detection and classification of plant-emitted volatile organic compounds (VOCs). The sensors were tested against linalool, trans-2-hexenal (T2H), and D-limonene at different concentrations under both dry and humid conditions (30% ± 3% RH). A Python-based (v3.13.5) signal-processing workflow was established to filter frequency responses and extract key features, such as baseline, saturation point, and frequency shift ($\Delta f$). Adsorption behaviour was modelled using the Freundlich isotherm, showing good agreement with experimental data and suggesting heterogeneous, multilayer adsorption on CH₃-terminated EC surfaces. A 2D polar classification framework combining vector-normalized $\Delta f$ values from UWAR and Sorex sensors enabled a clear separation of the VOCs. The results highlight the complementary performance of the two types of SMR sensors and demonstrate that feature-engineered resonant devices, combined with computational classification, offer strong potential for future use in plant health monitoring systems. Full article

Background: Aging is characterized by a decrease in olfactory, attentional, memory, language, and visuospatial/executive abilities. In this context, our study aimed to evaluate the potential effects of Rosmarinus officinalis L. (rosemary) and Carum carvi L. (caraway) essential oils (EOs) on aging. First, we assessed, in 402 participants, the age-related changes in olfactory functions (odor threshold, discrimination, and identification), gustatory perceptions (sweet, sour, salty, and bitter taste), cognitive functions (focusing on attention, memory, language, and visuospatial/executive functions), and their possible correlations with aging. To achieve this, olfactory function, gustatory perception, and cognitive abilities were evaluated in healthy participants across different age groups. Then, to evaluate the age-related decrease in trigeminal function (59 participants), we used rosemary and caraway EOs that contain carvone, limonene, and 1,8-cineole, all of which are considered typical trigeminal stimuli. Methods: Olfactory function was assessed with the Sniffin’ Sticks test, gustatory function by the Taste Strips test, and rosemary and caraway EOs by the ratings of odor pleasantness, intensity, and familiarity using a labeled hedonic Likert-type scale. Results: Olfactory function could be a potential early indicator of attentional, memory, language, and visuospatial/executive dysfunctions. Our data indicated that rosemary and caraway EOs were perceived without any significant decrease in odor pleasantness, intensity, and familiarity ratings in relation to aging. Conclusion: Our results suggest the potential bioactive effects of rosemary and caraway natural EOs as a new strategy to promote healthy aging. Full article

Biopolymers are increasingly explored as safer and more sustainable food packaging materials. This study evaluated the migration behavior of intentionally and non-intentionally added substances (IAS and NIAS), as well as the safety of gelatin and xanthan gum blends reinforced with microcrystalline cellulose, with and without oxygen plasma treatment, incorporating glycerol and limonene as plasticizers. Migration tests were conducted according to European Union (EU) Regulation No. 10/2011 using simulants of different polarities, and IAS/NIAS were analyzed by gas chromatography–mass spectrometry and ultra-high-pressure liquid chromatography–quadrupole time-of-flight mass spectrometry (GC–MS and UPLC-QTOF-MS). Films containing limonene were also evaluated for antioxidant activity. Results showed that plasticizer migration is strongly influenced by simulant polarity, glycerol predominantly migrated into hydrophilic media, whereas limonene and its derivatives exhibited higher migration in fatty simulants. Ethanol 95% acted as a conservative worst-case simulant, promoting extensive migration, while substantially lower migration levels were observed in isooctane and tenax plasma treatment resulted in modest changes in volatile compound migration, while significantly enhancing the antioxidant activity of limonene-containing films. Although overall migration levels were low under most of the tested conditions, NIAS formation, particularly from limonene degradation, highlights the need to account for chemical stability and simulant type when assessing bio-based films. Overall, the study demonstrates that film composition, surface modification, and simulant characteristics jointly influence migration behavior and functional performance under the evaluated conditions reinforcing the need to adapt current regulatory frameworks to the specific behavior of biopolymeric packaging materials. Full article

Mentha are historically important regarding their volatile oils. Since limited accounts exist for Australian species, we document the variation in volatiles across all Australian Mentha species, using the GC/MS of pentane extractions from leaf samples of replicate populations for all known species. Oil yields were consistently poor (<0.2% w/w) for freshly dried and herbarium specimens. Many species uniformly had high percentages of volatiles characteristically attributed to Mentha (viz. Menthone, Pulegone); yet, others—consistently or variably—lacked them. Mentha australis had the highest concentrations of menthone (25%), isomenthone, (9%) and pulegone (24%), and M. diemenica had menthone (32.5%) and pulegone (29.8%). Extracts from M. grandiflora from herbarium specimens produced weak traces, high in menthone and pulegone. Mentha satureioides had the highest menthone (20–30%) and pulegone (22–28%) in populations across the extent of its range; yet, an entirely different chemotype was identified from eastern New South Wales that contained limonene (17%), 1,8-cineole (19%), and α-terpineol (8%). Mentha laxiflora consistently exhibited limonene (27%); yet, the levels of the other main components (e.g., menthone, β-pinene, germacrene-D, and bicyclogermacrene) varied across populations. Mentha atrolilacina exhibited the most unique oil profile, with main components consisting of linalool (21%), β-caryophyllene (14%), germacrene-D (14%), and bicyclogermacrene (23.7%). Commercial samples of M. satureioides were found only to be the chemotype high in limonene (17%) and 1,8-cineole, which warrants further taxonomic research and caution for the industry seeking mint flavours from Australian sources. Full article

The increasing prevalence of antimicrobial resistance, especially in methicillin-resistant Staphylococcus aureus (MRSA), underscores the need for alternative therapies from natural sources. This study investigated the chemical composition, antibacterial activity, and gene expression modulation of Melaleuca cajuputi essential oils. Gas chromatography–mass spectrometry (GC-MS) identified 91 compounds, with naphthalene (23.90%), guaiol (12.92%), caryophyllene oxide (9.69%), D-limonene 98% (8.59%), and gamma terpinene (7.54%) among the most abundant. In Silico molecular docking against MRSA virulence proteins revealed that alloaromadendrene had the strongest binding to toxic shock syndrome toxin-1 (TSST-1) (−7.948 kcal/mol), suggesting high inhibitory potential, while cyclohexane showed weak binding with staphylococcal enterotoxin A (SEA) (−3.532 kcal/mol). Antibacterial assays demonstrated concentration-dependent inhibition, with the zones ranging from 6.33 ± 0.33 mm to 16.67 ± 0.88 mm. MIC and MBC values ranged from 1.56 to 12.5% and 3.13 to 25%, respectively, with most isolates showing bactericidal effects (MBC/MIC ≤ 2). Gene expression analysis of MRSA isolate 4 indicated that sea was moderately upregulated (FC = 1.44), while sec remained unchanged (FC = 1.02). In contrast, fnbA (FC = 0.72), seb (FC = 0.33), and mecA (FC = 0.23) genes were downregulated, and the tsst-1 gene (FC = 0.05) was nearly silent. These findings highlight M. cajuputi essential oils as a promising candidate with both antibacterial efficacy and regulatory effects on MRSA virulence genes. Full article

Common goldenrod (S. virgaurea L., Asteraceae) is recognised in traditional medicine as a folk remedy for kidney, urinary tract, and liver diseases, among others; however, its pharmaceutical potential remains largely unexplored. The pharmaceutical potential of the invasive species Canadian goldenrod (S. canadensis L.) in Europe is also of practical interest. The aim of the study was to compare the yield and composition of essential oils (EO) of flowering tops (20 cm long) of S. canadensis and S. virgaurea. The yield of EOs, hydrodistilled from S. canadensis (8 samples) and S. virgaurea (5 samples) herbs using the European Pharmacopoeia method, ranged from 2.7 to 14.9 mL/kg. The average EO yield in both goldenrod species was similar, but the composition differed. A total of 81 constituents were identified and semiquantified by GC-MS in the EOs of both Solidago species, eight of which have been found in these species for the first time. α-Pinene, limonene, and (E)-β-ocimene were the principal compounds in S. canadensis herb EO, and α-pinene, β-pinene, β-myrcene, and α-humulene were the principal compounds in S. virgaurea EO. It contained, on average, 39 times more benzyl salicylate than the EO from S. canadensis. Also, the amounts of viridiflorol (more in S. virgaurea) or β-bourbonene and (E)-β-ocimene (more in S. canadensis) can be used as a chemical fingerprint of both goldenrod species studied. The EO compositions were largely similar, with species-related differences supported by the presence of α-muurolene in S. virgaurea and its absence in S. canadensis. The pharmaceutical potential of V. canadensis as an invasive species is not yet sufficiently clear and requires further pharmacological studies. The composition of the EO seems to support the traditional use of goldenrod in the urological field. Full article