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A simple aqueous host:guest sensing array can selectively discriminate between different types of citrus varietal from peel extract samples. It can also distinguish between identical citrus samples at varying stages of ripening. The discrimination effects stem from detection of changes in the terpenoid composition of the peel extracts by the host:guest array, despite the overwhelming excess of a single component, limonene, in each sample. The hosts are insensitive to limonene but bind other monoterpenes strongly, even though they are similar in structure to the major limonene component. This work demonstrates the capability of host:guest arrays in sensing target molecules in environments with the competing agents present at high abundances in the sample matrix.

Background: Propolis was added to the European baseline series (EBS) in 2019. Objectives: To investigate the frequency and relevance of positive patch tests to propolis in the EBS and to study co‐reactivities. Patients and Methods: Retrospective study in patients patch tested between June 2019 and November 2023 in a university hospital in Amsterdam, The Netherlands. Results: Of 3134 consecutive patients, 299 (9.5%) had a positive reaction to propolis 10% pet. Only nine reactions (3%) were judged to be clinically relevant. There were significant co‐reactivities to Myroxylon pereirae resin (balsam of Peru), colophonium, fragrance mixes 1 and 2, and to limonene and linalool hydroperoxides. A steep increase in rates of positive reactions to propolis was observed from 2020 to 2023. This was highly likely the result of the replacement of Chinese propolis with Brazilian propolis by the manufacturer. Conclusions: Positive patch tests for propolis are very frequent in Amsterdam, but only a few of these reactions are relevant. Most are probably (pseudo‐)cross‐reactions in patients with fragrance allergies. Propolis in the EBS has very limited value for dermatologists and patients in The Netherlands. Changes in patch test materials should be provided to all users to avoid misinterpretation of patch test results. [ABSTRACT FROM AUTHOR]

Background Objectives Methods Results Conclusions Limonene and linalool are used in cosmetic products for their floral scents, but their oxidation products are strong contact allergens whose mechanisms of action are still not fully understood.The effects of limonene hydroperoxide (Lim‐2‐OOH) and linalool hydroperoxides (Lin‐6/7‐OOH) on the lipid profile of a human keratinocyte cell line (HaCaT) were evaluated. 2,4‐Dinitrofluorobenzene (DNFB) was also included.Lim‐2‐OOH and Lin‐6/7‐OOH were synthesised according to previous methods. HaCaT cells were treated with allergens (10 μM) for 24 h and the cellular lipid extracts were analysed by C18 liquid chromatography with tandem mass spectrometry (LC–MS/MS). Data analysis was performed using Lipostar software. Statistical analysis was carried out using Metaboanalyst and R software.All three sensitisers used caused significant changes in the lipidome of HaCaT cells in a similar trend. There was an upregulation in several plasmanyl/plasmenyl phospholipids (O‐/P‐phosphatidylcholines [PC] and O‐/P‐phosphatidylethanolamines [PE]), sphingolipids (HexCer) and triacylglycerol lipid species, and a decrease in some polyunsaturated fatty acids‐containing phospholipid (PE and PC) species suggesting oxidative stress and inflammation.This study is the first to evaluate the plasticity of the HaCaT cell lipidome in response to allylic hydroperoxide allergens Lim‐2‐OOH and Lin‐6/7‐OOH, together with the experimental contact allergen DNFB. These allergens are able to upregulate and downregulate certain lipid classes to a varying degree. [ABSTRACT FROM AUTHOR]

The aim of this study was to analyse the essential oil of Lavandula dentata from Algeria and to test the antioxidant and antimicrobial properties of this plant. The essential oil (EO) (57 constituents) included mainly α-pinene, β-pinene, nopinone, linalool, cryptone, and limonene. The plant polyphenolic contents and the antioxidant activity were determined. The antimicrobial effect of the EO and the methanolic extract (ME) was assessed against referenced and clinical bacterial strains, and also foodborne fungal isolates. The EO minimal inhibitory concentration (MIC) values varied from 0.25 to 4 mg/mL and minimal bactericidal concentrations (MBCs) were less than 8 mg/mL except for S. aureus, clinical Klebsiella, S. epidermidis, and B. subtilis. The mould strains were significantly inhibited by the EO (87.50% to 88.33%). The MIC values were 3.60–15.62 mg/mL and 0.5–4 mg/mL for ME and EO, respectively. The minimal fungicidal concentration (MFC) values ranged from 31 to 125 mg/mL and from 2 to 8 mg/mL for ME and EO, respectively. [ABSTRACT FROM AUTHOR]

Aim: Environmental exposure constitutes a significant determinant in the pathogenesis of metabolic syndrome (MetS). Nevertheless, the contribution of environmental factors to MetS remains ambiguous. The present study was aimed at investigating the correlation between serum terpenes and the risk of MetS in the general population. Methods: A cross‐sectional study was conducted among 1266 individuals from the 2013–2014 National Health and Nutrition Examination Survey (NHANES). Serum terpenes and MetS risk were analyzed using a weighted logistic regression model. Weighted quantile sum (WQS) regression was utilized to explore the relationship between the mixture of serum terpenes and MetS. The restricted cubic spline (RCS) method was employed to assess the dose–response relationship between them. All data and analyses were conducted using the "Survey" package in R software (Version 4.3.2). Results: The study population, with an average age of 46.82 ± 0.46 years and a body mass index (BMI) of 28.97 kg/m2, consisted of 48.15% males and 67.99% Whites. Among the participants, 35.78% were diagnosed with MetS. The weighted logistic regression showed that tertiles of serum levels of α‐pinene, β‐pinene, and limonene were positively correlated with MetS risk with a OR value of 1.90 (1.14, 3.16), 2.02 (1.23, 3.31), and 2.35 (1.33, 4.13) and elevated triglycerides (TGs) with a OR of 2.36 (1.63, 3.43), 3.51 (2.30, 5.38), and 3.96 (2.55, 6.15) (all ptrend < 0.05). The WQS regression indicated a positive association between serum terpene mixture and MetS risk (OR = 1.65, 95% CI: 1.18–2.3), increased TG (OR = 2.69, 95% CI: 1.94–3.71), and reduced high‐density lipoprotein cholesterol (HDL‐C) (OR = 1.46, 95% CI: 1.03–2.07) (all ptrend < 0.01). The RCS analysis further supported the dose–response relationship. Conclusion: This study suggested potential adverse effects of terpene exposure on human health, emphasizing the importance of environmental interventions in maintaining health. [ABSTRACT FROM AUTHOR]

Coniferous trees produce secondary or defense chemicals, such as terpenes, against pest insects. Terpenes could serve as constitutive or induced defensive mechanisms, defending the tree from invasive herbivores. The Mediterranean pine shoot beetle Tomicus destruens colonizes stems and branches of Pinus brutia trees and even can kill mature trees during periodic outbreaks. We investigated whether terpene profiles of needle and stem of P. brutia trees differ between health and those infested by T. destruens. We selected 20 healthy and T. destruens-infested trees and analyzed the monoterpenes and sesquiterpenes of their needles and phloem. We found higher concentrations of tricyclene, camphene and p-cymene in the phloem of infested trees. Similarly, the needles of infested trees had higher concentrations of α-pinene, β-pinene, myrcene, limonene, trans-β-caryophyllene and α-humulene than healthy trees. These results show that the monoterpene and sesquiterpene profiles of P. brutia trees differed between healthy and infested trees, suggesting that volatile terpenes may be an important part of plant-induced responses against T. destruens. [ABSTRACT FROM AUTHOR]

Engineered microorganisms have emerged as viable alternatives for limonene production. However, issues such as low enzyme abundance or activities, and regulatory feedback/forward inhibition may reduce yields. To understand the underlying metabolism, we adopted a systems biology approach for an engineered limonene-producing Escherichia coli strain K-12 MG1655. Firstly, we generated time-series metabolomics data and, secondly, developed a dynamic model based on enzyme dynamics to track the native metabolic networks and the engineered mevalonate pathway. After several iterations of model fitting with experimental profiles, which also included 13C-tracer studies, we performed in silico knockouts (KOs) of all enzymes to identify bottleneck(s) for optimal limonene yields. The simulations indicated that ALDH/ADH (aldehyde dehydrogenase/alcohol dehydrogenase) and LDH (lactate dehydrogenase) suppression, and HK (hexokinase) enhancement would increase limonene yields. Experimental confirmation was achieved, where ALDH-ADH and LDH KOs, and HK overexpression improved limonene yield by 8- to 11-fold. Our systems biology approach can guide microbial strain re-engineering for optimal target production. [ABSTRACT FROM AUTHOR]

S‐Limonene (s‐Lim) is a monocyclic monoterpene found in a variety of plants and has been shown to present antioxidant and cardioprotective activity in experimental models of myocardial infarction. The aim of this study was to evaluate the potential mechanism by which s‐Lim exerts its antiarrhythmic effect, focusing on the blockade of β‐adrenoceptor (β‐AR) and its effects on various in vivo and in vitro parameters, including electrocardiogram (ECG) measurements, left ventricular developed pressure (LVDP), the β‐adrenergic pathway, sarcomeric shortening and L‐type calcium current (ICa,L). In isolated hearts, 10 μM of s‐Lim did not alter the ECG profile or LVPD. s‐Lim increased the heart rate corrected QT interval (QTc) (10.8%) at 50 μM and reduced heart rate at the concentrations of 30 (12.4%) and 50 μM (16.6%). s‐Lim (10 μM) also inhibited the adrenergic response evoked by isoproterenol (ISO) (1 μM) reducing the increased of heart rate, LVDP and ECG changes. In ventricular cardiomyocyte, s‐Lim antagonized the effect of dobutamine by preventing the increase of sarcomeric shortening, demonstrating a similar effect to atenolol (blocker β1‐AR). In vivo, s‐Lim antagonized the effect of ISO (agonists β1‐AR), presenting a similar effect to propranolol (a non‐selective blocker β‐AR). In ventricular cardiomyocyte, s‐Lim did not alter the voltage dependence for ICa,L activation or the ICa,L density. In addition, s‐Lim did not affect changes in the ECG effect mediated by 5 μM forskolin (an activator of adenylate cyclase). In an in vivo caffeine/ISO‐induced arrhythmia model, s‐Lim (1 mg/kg) presented antiarrhythmic action verified by a reduced arrhythmia score, heart rate, and occurrence of ventricular premature beats and inappropriate sinus tachycardia. These findings indicate that the antiarrhythmic activity of s‐Lim is related to blockade of β‐AR in the heart. [ABSTRACT FROM AUTHOR]

Summary Terpene synthases (TPSs) are key enzymes in terpenoids synthesis of plants and play crucial roles in regulating plant defence against pests and diseases. Here, we report the functional characterization of OsTPS19 and OsTPS20, which were upregulated by the attack of brown planthopper (BPH). BPH female adults performed concentration‐dependent behavioural responses to (S)‐limonene showing preference behaviour at low concentrations and avoidance behaviour at high concentrations. Overexpression lines of OsTPS19 and OsTPS20, which emitted higher amounts of the monoterpene (S)‐limonene, decreased the hatching rate of BPH eggs, reduced the lesion length of sheath blight caused by Rhizoctonia solani and bacterial blight caused by Xanthomonas oryzae. While knockout lines of OsTPS19 and OsTPS20, which emitted lower amounts of (S)‐limonene, were more susceptible to these pathogens. Overexpression of OsTPS19 and OsTPS20 in rice plants had adverse effects on the incidence of BPH, rice blast, and sheath blight in the field and had no significant impacts on rice yield traits. OsTPS19 and OsTPS20 were found to be involved in fine‐tuning the emission of (S)‐limonene in rice plants and play an important role in defence against both BPH and rice pathogens. [ABSTRACT FROM AUTHOR]

There is high market demand for (−)‐menthol because of its unique aroma and cooling properties. The first bottleneck encountered in the biosynthesis of (−)‐menthol in Escherichia coli is the low hydroxylation efficiency of (−)‐limonene‐3‐hydroxylase. Few known enzymes can hydroxylate the third carbon atom of (−)‐limonene. In this work, initially, we searched for new enzymes and screened a library of cytochrome P450BM3 variants aiming to improve catalysis of this reaction, but did not identify any variants with improved activity or regioselectivity. Then, through protein engineering of a cytochrome P450 monooxygenase variant from Pseudomonas putida (PpcamY96F/V247L), we obtained variant PpcamF87W/Y96F/L244I/V247L/V396A with regioselectivity of 93% (starting from 70%) toward (−)‐limonene without losing activity. Because of the improvement in regioselectivity, its turnover number was 1.5 times that of the starting enzyme. We analyzed the reasons for the improvement through molecular dynamics simulations. The new variant also exhibited 95% regioselectivity toward (+)‐limonene. This enzyme variant can be applied in biosynthesis of (−)‐menthol. [ABSTRACT FROM AUTHOR]

Naturally occurring and structurally diverse alkene-containing substrates, terpenes, provided a platform for establishing chemo-, regio-, and diastereoselective reactivity in tantalum catalysed hydroaminoalkylation. Naturally derived 1,3-butadienes revealed the unique regio- and diastereoselective (Z)-1,4-addition products accessible from isoprene and β-myrcene by hydroaminoalkylation. Selective terpene functionalisation, within an industrially produced turpentine mixture, demonstrates functionalisation specificity of β-pinene and limonene. Lastly, sesquiterpene functionalisation using β-caryophyllene and humulene provide rare examples of trisubstituted alkene reactivity in hydroaminoalkylation, by leveraging strainrelease and stereoelectronic effects to control chemoselectivity. As a result of these reactivity studies using natural substrates, new tools for understanding alkene electronic, strain, and stereoelectronic effects on chemo- and diastereoselectivity outcomes have revealed new mechanistic insights into hydroaminoalkylation. [ABSTRACT FROM AUTHOR]

AbstractIn indoor air the reaction of ozone (O3) with terpenes may lead to the formation of irritating gas-phase products which may induce acute airway effects (i.e. sudden, short-term changes or symptoms related to the respiratory system). We aimed to perform an in vitro study on possible health effects of products from the O3-initiated reaction of limonene with printer exhaust, representing real-life mixtures in offices. Human bronchial epithelial cells were exposed for 1 hour (h) to limonene and O3, combined with printer exhaust. The resulting concentrations represented 34% and 6% of the generated initial concentrations of limonene (400 µg/m³) and O3 (417 µg/cm³), respectively, which were in range of high end realistic indoor concentrations. We observed that the reaction of limonene with O3 generated an increase of ultrafine particles within 1 h, with a significant increase of secondary reaction products 4-oxopentanal and 3-isopropenyl-6-oxo-heptanal at high end indoor air levels. Simultaneous printing activity caused the additional release of micron-sized particles and a further increase in reaction products. Relevant cellular endpoints to evaluate the possible induction of acute airway effects were measured. However, none of the test atmospheres representing office air was observed to induce these effects. [ABSTRACT FROM AUTHOR]

BACKGROUND RESULTS CONCLUSION Carvone and limonene are naturally occurring monoterpenoids with unique aromas, making them valuable substances in synthetic fragrance production. However, their application is limited due to low stability and rapid volatilization. To address this challenge, host–guest complexes offer a promising solution.In this study, two acyclic cucurbit[n]urils were synthesized to form inclusion complexes with carvone and limonene, aiming to enhance their thermal stability and achieve excellent heat release properties. The binding behavior of the complexes was investigated using NMR, X‐ray diffraction (XRD), Fourier transform infrared (FTIR) and molecular bonding analyses, confirming the formation of host–guest inclusion complexes.Our study successfully prepared four inclusion complexes (M1/CA, M2/CA, M1/LI, M2/LI) and characterized them using NMR, XRD and FTIR techniques. These complexes exhibited a 1:1 stoichiometric ratio, and their binding constants were determined through fluorescence titration. The thermal controlled release experiment shows that the degree of carvone and limonene release is different with a change of temperature, indicating that the inclusion complexes have good thermally controlled release performance, and the thermal release retention rate has a certain correlation with KS value. The larger the KS value, the higher the thermal release retention rate of the inclusion complexes, the lower the volatilization of the inclusion complexes, the longer the retention time and the better the thermal stability. This study presents a novel approach for developing carvone‐ and limonene‐based fragrances, expanding their application potential in various industries. © 2024 Society of Chemical Industry. [ABSTRACT FROM AUTHOR]

Angelica is a large genus of plants belonging to the Apiaceae family that includes about 100 species of biennial or perennial herbs. Several species of this genus are extensively used in various traditional medicines and, despite their content in toxic furanocoumarins, also as food. In this study, the chemical composition of the essential oil (EO) from aerial flowering parts of Angelica sylvestris L., a plant distributed in Europe, North and Central Asia, collected in the Isle of Skey (Scotland), was analyzed by GC and GC-MS. No one report has been previously published on this accession. The result showed the presence of a large quantity of monoterpene hydrocarbons with limonene (51.89%), by far, as the most abundant component. Other metabolites present in lesser quantity were β-pinene (4.61%), α-pinene (3.54%), and thymol (3.33%). Considerations with respect to all the other EOs of A. sylvestris taxa, studied so far, were carried out. [ABSTRACT FROM AUTHOR]

In this study, 13 different edible weed species [Centaurea depressa Bieb., Cichorium intybus L., Lactuca serriola L., Malva neglecta Wallr., Papaver dubium L., Polygonum cognatum Meissn., Rumex patientia L., Scorzonera cana (C.A.Mey.Hoffm.), Silene alba (Mill.) Krause, Stellaria media L., Sonchus oleraceus L., Taraxacum officinale, Tragopogon longirostris Bisch] were collected from the same location in the Mediterranean region. Then, the leaves of all species were analyzed by the SPME-GC/MS method for the detection of volatile compounds. The compounds were grouped according to their structures as alcohols, aldehydes, alkanes, ester, furans, hydrocarbons, ketones, sulfur compounds, and terpenes. The percentages of the terpenes, aldehydes and alcoholic compounds were found to have the highest ratios of volatile compounds, respectively. The species found with the highest total terpene percentage was Sonchus oleraceus L. (78.84%), while the lowest one was Stellaria media L. (51.03%). Similarly, the highest total aldehydes percentage was found in Stellaria media L. (38.41%), and the lowest was in Centaurea depressa Bieb. (4.62%). Lastly, the highest total alcohol percentage was observed in Centaurea depressa Bieb. (9.92%) and the lowest was in Malva neglecta Wallr. (1.11%). The limonene, which is an important monoterpene, among 63 components, was found to be the major component in all species with a range of approximately 51-79%. Among them, Sonchus oleraceus L. had the highest limonene content (78.84%). [ABSTRACT FROM AUTHOR]

There has been much recent interest in whole‐room far‐UVC (wavelength around 222 nm) to markedly and safely reduce overall levels of airborne pathogens in occupied indoor locations. Far‐UVC light produces very low levels of ozone—in real‐world scenarios induced ozone levels of less than 10 ppb, and much less in moderately or well‐ventilated rooms compliant with US far‐UVC dose recommendations, and very much less in rooms compliant with international far‐UVC dose standards. At these very low ozone levels, there is no epidemiological evidence of increased health risks from any of the very large outdoor ozone studies, whether from ozone alone or from ozone plus associated pollutants. Indoors, at the low ozone concentrations of relevance here, ozone does not react rapidly enough with preexisting airborne volatile organic compounds to compete with even extremely low levels of room ventilation, so significant ozone‐induced ultrafine particle production is very unlikely. Direct measurements in real‐life room scenarios are consistent with these conclusions. A potential exception is the cleaning material limonene, which has an unusually high ozone interaction cross‐section; in the far‐UVC context, turning off far‐UVC lights during cleaning with limonene products would be reasonable. [ABSTRACT FROM AUTHOR]

Bergamot (Citrus bergamia Risso) is not consumed as fresh fruit as other members of Citrus. Bergamot essential oil has a unique aroma. Bergamot essential oil is a very valuable product used in perfumery, cosmetics, aromatherapy and food industry due to its beautiful scent and functional properties. As with other Citrus species, the composition of bergamot essential oil can vary according to harvest time, climate and extraction technology. Bergamot essential oil could be obtained by cold press extraction or distillation method. Within the scope of the study, the effect of four different hydrodistillation (HD) times (5, 10, 60 and 120 min) on the composition of bergamot essential oil obtained from Turkish fruits was investigated. In the first 60 min, 96.11% of the total essential oil was obtained. Research findings have shown that the distillation time is quite effective in the composition of bergamot essential oil. Limonene, linalool and linalyl acetate, which are the main components of bergamot essential oil, varied in the range, 42.36%–53.25%, 5.59%–12.18% and 20.84%–26.73%, respectively, with respect to distillation time. In cold press method, bergamot essential oil has lower linalool/linalyl acetate ratio (0.15) compared to HD method and a higher quality essence was obtained. [ABSTRACT FROM AUTHOR]

In this research, nanostructured lipid carriers (NLCs) loaded with limonene were developed using various solid lipids. The impact of high temperatures on the characteristics of NLCs was investigated. NLCs exhibited zeta potential values exceeding |30| mV, indicating excellent homogeneity and stability. Increasing the carbon chain length of monoglycerides from C15 to C21 resulted in a corresponding increase in particle size of NLCs from 219.1 ± 1.1 to 243.3 ± 0.9 nm. However, the particle size remained relatively constant with an increase in the number of solid lipid carbon chains. Encapsulation efficiency of limonene increased from 66.0 ± 0.7% to 86.2 ± 0.8% with an increase in the number of solid lipid carbon chains. The result showed that more ester bonds facilitated the dissolution of the target and enhanced the interaction forces between solid lipids and the target. X‐ray diffraction, Fourier transform‐infra‐red spectroscopy and differential scanning calorimetry analyses confirmed effective encapsulation of limonene in NLCs, resulting in good stability. NLCs prepared from various solid lipids exhibited varying properties. Glycerol triglyceride demonstrated superior stability and homogeneity of nanoparticles under high‐temperature conditions compared to other solid lipids. This study provides enhancing the thermal stability of limonene‐loaded NLCs and proposes a novel approach for their practical application. [ABSTRACT FROM AUTHOR]

Copyright of Shipin Kexue/ Food Science is the property of Food Science Editorial Department and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The antiviral efficacy of cell-extracts (CEs) derived from cypress (Chamaecyparis obtusa (Siebold & Zucc.) Endl., C. obtusa) and cedar (Cryptomeria japonica (Thunb. ex. L.) D.Don, C. japonica) was assessed using phi6 and MS2 bacteriophages, which are widely accepted surrogate models for enveloped and non-enveloped viruses, in order to verify their potential use as antiviral agents. Our results indicate that CEs derived from C. obtusa are dominantly composed of terpinen-4-ol (18.0%), α-terpinyl acetate (10.1%), bornyl acetate (9.7%), limonene (7.1%), and γ-terpinene (6.7%), while CEs derived from C. japonica are dominantly composed of terpinen-4-ol (48.0%) and α-pinene (15.9%), which exhibited robust antiviral activity against phi6 bacteriophage. Both CEs successfully inactivated the phi6 bacteriophage below the detection limit (10 PFU/mL) within a short exposure time of 30 s (log reduction value, LRV > 4). Through exposure experiments utilizing CEs with content ratios prepared via 2-fold serial dilutions (ranging from 3.13% to 100%), we demonstrated that the antiviral effect could be sustained up to a concentration of 25% (C. obtusa LRV = 3.8, C. japonica LRV > 4.3 at a 25% CE content ratio for each species). However, CEs with content ratios below 12.5% did not produce a significant reduction in bacteriophage concentration and consequently lost their antiviral effects. Conversely, both CEs did not exhibit antiviral activity against MS2 bacteriophage, a non-enveloped virus. Our findings reveal for the first time the potential of CEs derived from C. obtusa and C. japonica for use as antiviral agents specifically targeting enveloped viruses. [ABSTRACT FROM AUTHOR]

Copyright of Boletín Latinoamericano y del Caribe de Plantas Medicinales y Aromáticas is the property of Universidad de Santiago de Chile and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The use of household bleach cleaning products results in emissions of highly oxidative gaseous species, such as hypochlorous acid (HOCl) and chlorine (Cl2). These species readily react with volatile organic compounds (VOCs), such as limonene, one of the most abundant compounds found in indoor enviroments. In this study, reactions of HOCl/Cl2 with limonene in the gas phase and on indoor relevant surfaces were investigated. Using an environmental Teflon chamber, we show that silica (SiO2), a proxy for window glass, and rutile (TiO2), a component of paint and self-cleaning surfaces, act as a reservoir for adsorption of gas-phase products formed between HOCl/Cl2 and limonene. Furthermore, high-resolution mass spectrometry (HRMS) shows that the gas-phase reaction products of HOCl/Cl2 and limonene readily adsorb on both SiO2 and TiO2. Surface-mediated reactions can also occur, leading to the formation of new chlorine- and oxygen-containing products. Transmission Fourier-transform infrared (FTIR) spectroscopy of adsorption and desorption of bleach and terpene oxidation products indicates that these chlorine- and oxygen-containing products strongly adsorb on both SiO2 and TiO2 surfaces for days, providing potential sources of human exposure and sinks for additional heterogeneous reactions.

The compositional dependency of the essential oil of Clinopodium menthifolium subsp. menthifolium (Lamiaceae) on ecological conditions has not yet been investigated. In pursuit of this objective, we assessed the quantity and quality of the essential oil in plants from 11 natural populations from the Central Balkans and one cultivated plant. In order to determine the correlations between essential oil variations and environmental conditions, each habitat was characterised by 36 climatic and 19 bioclimatic parameters. Despite inhabiting diverse climatic zones, altitudes, and biogeographical regions, no significant differences were observed in the yield and qualitative and quantitative composition of the essential oils among the analysed plants. All the samples exhibited essential oil yield ≥ 0.5%, V/w, with piperitone epoxide as the major compound. Among the identified compounds, only limonene and (E)-caryophyllene demonstrated dependence on bioclimatic parameters. The bioclimatic parameters which influence the presence of a larger number of compounds are annual temperature range and the precipitation of the wettest quarter. The consistent quantity and quality of the essential oils of C. menthifolium subsp. menthifolium indicate their probable adaptive significance and could serve as chemotaxonomic features of this taxon.

A food self-heater is a device designed to rapidly heat food by the utilization of exothermic or endothermic reactions. To yet, a food self-heater with a dedicated scent feature has not been developed. The fragrance utilized is derived from residual tangerine peel components. The objective of this study is to investigate the variations in the concentration of the limonene compound in essential oil extracted from tangerine peel, specifically examining the impact of tangerine peel wilting. Additionally, the study intends to identify the most effective food self-heating method by incorporating tangerine peel powder as an aromatic component in the self-heating process. The present study employed a Completely Randomized Design (CRD) consisting of five treatments and three replications. The treatments employed in this study encompassed varying durations of withering time for tangerine peel, denoted as A (0 hours), B (6 hours), C (12 hours), D (24 hours), and E (48 hours). The research findings indicated that the duration of drying tangerine peels had a notable impact on various factors including water content, yield, pH, color, duration for the aromatic self-heating meal to attain the optimal temperature, and aroma. However, no significant influence on limonene levels was seen. Based on the duration required for the aromatic food self-heater to attain the optimal temperature and the organoleptic aroma, treatment D (24-hour withering of tangerine peel) demonstrates the highest efficacy. This treatment exhibits a time frame of approximately 4.5 minutes for the aromatic food self-heater to reach the optimum temperature, accompanied by a fragrance rating of 4.2 in the organoleptic analysis.

Abstract In this research, nanostructured lipid carriers (NLCs) loaded with limonene were developed using various solid lipids. The impact of high temperatures on the characteristics of NLCs was investigated. NLCs exhibited zeta potential values exceeding |30| mV, indicating excellent homogeneity and stability. Increasing the carbon chain length of monoglycerides from C15 to C21 resulted in a corresponding increase in particle size of NLCs from 219.1 ± 1.1 to 243.3 ± 0.9 nm. However, the particle size remained relatively constant with an increase in the number of solid lipid carbon chains. Encapsulation efficiency of limonene increased from 66.0 ± 0.7% to 86.2 ± 0.8% with an increase in the number of solid lipid carbon chains. The result showed that more ester bonds facilitated the dissolution of the target and enhanced the interaction forces between solid lipids and the target. X‐ray diffraction, Fourier transform‐infra‐red spectroscopy and differential scanning calorimetry analyses confirmed effective encapsulation of limonene in NLCs, resulting in good stability. NLCs prepared from various solid lipids exhibited varying properties. Glycerol triglyceride demonstrated superior stability and homogeneity of nanoparticles under high‐temperature conditions compared to other solid lipids. This study provides enhancing the thermal stability of limonene‐loaded NLCs and proposes a novel approach for their practical application.

Abstract Recent studies have explored the antioxidant properties of lemon essential oil (LEO), taking considering factors like plant part, extraction methods, and antioxidant assay. However, due to varied results and limited precision in individual studies, our meta-analysis aims to offer a comprehensive understanding across different experiments, irrespective of location or time. Out of 109 scientific articles published between 1947 and 2024, only 28 successfully validated their data on differences in antioxidant capacity and IC50, using weighted averages of Hedges’ d in meta-analysis. A meta-analysis revealed several key findings: (i) lemon leaf and peel extracts have higher IC50 compared to controls, whereas whole plant extracts show lower values (p

Abstract Background Limonene has a variety of applications in the foods, cosmetics, pharmaceuticals, biomaterials, and biofuels industries. In order to meet the growing demand for sustainable production of limonene at industry scale, it is essential to find an alternative production system to traditional plant extraction. A promising and eco-friendly alternative is the use of microbes as cell factories for the synthesis of limonene. Results In this study, the oleaginous yeast Yarrowia lipolytica has been engineered to produce d- and l-limonene. Four target genes, l- or d-LS (limonene synthase), HMG (HMG-CoA reductase), ERG20 (geranyl diphosphate synthase), and NDPS1 (neryl diphosphate) were expressed individually or fused together to find the optimal combination for higher limonene production. The strain expressing HMGR and the fusion protein ERG20-LS was the best limonene producer and, therefore, selected for further improvement. By increasing the expression of target genes and optimizing initial OD, 29.4 mg/L of l-limonene and 24.8 mg/L of d-limonene were obtained. We also studied whether peroxisomal compartmentalization of the synthesis pathway was beneficial for limonene production. The introduction of d-LS and ERG20 within the peroxisome improved limonene titers over cytosolic expression. Then, the entire MVA pathway was targeted to the peroxisome to improve precursor supply, which increased d-limonene production to 47.8 mg/L. Finally, through the optimization of fermentation conditions, d-limonene production titer reached 69.3 mg/L. Conclusions In this work, Y. lipolytica was successfully engineered to produce limonene. Our results showed that higher production of limonene was achieved when the synthesis pathway was targeted to the peroxisome, which indicates that this organelle can favor the bioproduction of terpenes in yeasts. This study opens new avenues for the efficient synthesis of valuable monoterpenes in Y. lipolytica.

The essential oils derived from various coniferous species, including Cupressus torulosa, have been historically valued for their aromatic properties. In the present study, essential oil from C. torulosa needles (CTEO) was analyzed using Gas Chromatography (GC), Gas Chromatography-Mass Spectrometry (GC-MS), and Gas Chromatography-Olfactometry (GC-O) with Aroma Extract Dilution Analysis (AEDA). A total of 36 compounds were identified, with δ-3-carene (0.1824 ± 0.0084 mg/g), sabinene (0.1125 ± 0.036 mg/g), and terpinen-4-ol (0.0891 ± 0.0034 mg/g) as major constituents. Of these, 24 were odor-active. The aroma profile of CTEO featured top notes of green, fresh leafy, cool, fruity, and citrus scents, middle notes of dry woody tones, and base notes of spicy and dry characteristics. Predictive models including FD factor, Odor Activity Values, and Relative Flavor Activity highlighted α-pinene, α-terpinene, linalool, bornyl acetate, β-pinene, camphor, limonene, and terpinen-4-ol as key aroma contributors. This study provides valuable insights into the aromatic profile of CTEO, with potential applications in the aroma industry. [ABSTRACT FROM AUTHOR]

[(Bn-tpen)FeII(MeCN)](ClO4)2, containing the pentadentate Bn-tpen–N-benzyl-N,N′,N′-tris(2-pyridylmethyl)-1,2-diaminoethane ligand, was studied in the oxygenation of cyclohexene and limonene using low-pressure dioxygen (0.2 atm air or 1 atm pure O2) in acetonitrile. 2-Cyclohexen-1-one and 2-cyclohexen-1-ol are the main products of cyclohexene oxidations, with cyclohexene oxide as a minor product. Limonene is oxidized to limonene oxide, carvone, and carveol. Other oxidation products such as perillaldehyde and perillyl alcohol are found in trace amounts. This catalyst is slightly less active than the previously reported [(N4Py)FeII(MeCN)](ClO4)2 (N4Py–N,N-bis(2-pyridylmethyl)-N-(bis-2-pyridylmethyl)amine). Based on cyclic voltammetry experiments, it is postulated that [(Bn-tpen)FeIV=O]2+ is the active species. The induction period of approx. 3 h during cyclohexene oxygenation is probably caused by deactivation of the reactive Fe(IV)=O species by the parent Fe(II) complex. Equimolar mixtures of Fe(II) salt and the ligand (in situ-formed catalyst) gave catalytic performance similar to that of the synthesized catalyst. [ABSTRACT FROM AUTHOR]

Limonene, a dietary monocyclic monoterpene commonly found in citrus fruits and various aromatic plants, has garnered increasing interest as a gastrointestinal protectant. This study aimed to assess the effects of limonene on intestinal epithelial barrier function and investigate the involvement of cannabinoid receptor type‐1 (CB1R) in vitro. Additionally, the study focused on examining the metabolomic changes induced by limonene in the intestinal epithelial cells (Caco‐2). Initial analysis of transepithelial electrical resistance (TEER) revealed that both l‐limonene and d‐limonene, isomers of limonene, led to a dose‐ and time‐dependent increase in TEER in normal cells and those inflamed by pro‐inflammatory cytokines mixture (CytoMix). Furthermore, both types of limonene reduced CytoMix‐induced paracellular permeability, as demonstrated by a decrease in Lucifer yellow flux. Moreover, d‐limonene and l‐limonene treatment increased the expression of tight junction molecules (TJs) such as occludin, claudin‐1, and ZO‐1, at both the transcriptional and translational levels. d‐Limonene upregulates E‐cadherin, a molecule involved in adherens junctions (AJs). Mechanistic investigations demonstrated that d‐limonene and l‐limonene treatment significantly inhibited CB1R at the protein, while the mRNA level remained unchanged. Notably, the inhibitory effect of d‐limonene on CB1R was remarkably similar to that of pharmacological CB1R antagonists, such as rimonabant and ORG27569. d‐limonene also alters Caco‐2 cell metabolites. A substantial reduction in β‐glucose and 2‐succinamate was detected, suggesting limonene may impact intestinal epithelial cells' glucose uptake and glutamate metabolism. These findings suggest that d‐limonene's CB1R antagonistic property could effectively aid in the recovery of intestinal barrier damage, marking it a promising gastrointestinal protectant. [ABSTRACT FROM AUTHOR]

Volatile organic compounds (VOCs) in food are key factors constituting their unique flavor, while the characteristics of VOCs in air-dried yak meat (AYM) from various regions of the Tibetan Plateau and their inter-regional differences remain unclear. Therefore, this study conducted a comprehensive analysis of VOCs in the five-spice (FS), spicy and numbing (SN), and aromatic and spicy (AS) versions of AYM from four regions of the Tibetan Plateau (Gansu, Qinghai, Sichuan, and Tibet) using gas chromatography–ion mobility spectrometry (GC–IMS) A total of 58 VOCs were identified, with alcohols accounting for 28.40%, ketones 22.89%, aldehydes 18.85%, and terpenes 17.61%. Topographic plots, fingerprint profiles, and multivariate analysis not only distinguished AYM of the same flavor from different regions but also discriminated those of different flavors within the same region. Furthermore, 17 key VOCs were selected as the primary aroma characteristics of the 12 types of AYM, including linalool, 3-methylbutanal, acetone, and limonene. Meanwhile, the differential VOCs for each flavor were determined, with linalyl acetate being unique to the FS, (E)-ocimene and ethyl propanoate being specific to the SN, and 2-methyl-3-(methylthio)furan-D and Hexanal-D being characteristic of the AS flavor. Based on the above results, the flavor of AYM can be improved to suit the taste of most people and increase its consumption. [ABSTRACT FROM AUTHOR]

The Zingiber genus has been widely applied in food and pharmaceuticals due to its varied chemical composition and significant benefits. Zingiber plicatum Škorničk. & Q.B. Nguyễn was described in Vietnam in 2015, yet there has been no report on its phytochemicals and bioactivity. In this study, we first analyzed the chemical composition of essential oil and its antioxidant activities. Isolation of the rhizome essential oil was performed through hydrodistillation using a Clevenger apparatus for 3.5 h, then volatile compositions were determined using gas chromatography-mass spectroscopy (GC-MS). Additionally, the antioxidant activities were assessed using 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging and ferric reducing power assays. The GC-MS analysis showed a total of 54 volatile components, mainly belonging to monoterpene hydrocarbons (57.69%) and sesquiterpene hydrocarbons (28.98%). The main compounds were β-pinene (26.85%), α-pinene (11.73%), limonene (10.03%), and germacrene D (5.26%). The essential oil also showed antioxidant activities, with an IC50 of 84.53 mg/mL for DPPH scavenging activity and an EC50 of 17.3 mg/mL for ferric reducing power. These findings first provided data on the chemical components and antioxidant properties of Z. plicatum essential oil. [ABSTRACT FROM AUTHOR]

Pistacia palaestina Boiss. is a common tree in the Mediterranean maquis. The leaves of this plant accumulate defensive monoterpenes, whose levels greatly increase in galls induced by the aphid Baizongia pistaciae. We previously found a significant chemopolymorphism in monoterpene content among individual trees, but the chirality of these monoterpenes was unknown. Although most plant species specifically accumulate one enantiomeric form of a given compound, P. palaestina individuals display chemopolymorphism in the chirality of the key monoterpenes accumulated. We report here a marked enantiomeric variation for the limonene, α‐ and β‐pinene, camphene, sabinene, δ‐3‐carene, and terpene‐4‐ol content in leaves and galls of nine different naturally growing P. palaestina trees. Interestingly, insect‐induced gall monoterpene composition is an augmentation of the specific enantiopolymorphism originally displayed by each individual tree. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Chinese Institute of Food Science & Technology is the property of Journal of Chinese Institute of Food Science & Technology Periodical Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Monensin and essential oils have antimicrobial properties that may impact silage fermentation. The present study was divided into two trials to evaluate the effects of monensin (MON) and essential limonene oils (ELO) as additives in the ensiling of total mixed ration (TMR). In the first assay, TMR was tested with sheep in growth (65% dry matter—DM) using the following treatments: control (no additive), MON35 (35 mg of monensina per kg of DM), MON45 (45 mg of monensina per kg of DM), ELO300 (300 mg of essential limonene oil per kg of DM), and ELO600 (600 mg of essential limonene oil per kg of DM). In the second assay, the same treatments were used in TMR for lactating cows under two moisture conditions (30% and 40% DM). The parameters assessed included fermentative losses, short-chain fatty acid profiles, aerobic stability (hours needed for silage to reach 2 °C above ambient), chemical composition, and in vitro DM digestibility of the silages. Treatment averages were compared using the Scott–Knott test at 5% significance. In the first assay, the treatments with ELO had the lowest (p < 0.05) pH values and the highest (p < 0.05) lactic acid concentrations, with treatment ELO600 leading to the highest (p < 0.05) aerobic stability (297.88 h). Only the starch contents of the ELO treatments were lower (p < 0.05) than the others. In the second assay, the silages with the highest moisture contents and ELO600 exhibited the lowest (p < 0.05) values of DM recovery, lactic acid, and pH. The highest (p < 0.05) lactic acid:acetic acid ratios were observed in the silages with the most moisture added with MON35 and MON45. The use of MON and ELO increased aerobic stability, with the highest (p < 0.05) values observed for ELO600 and MON35. The treatments with MON and ELO resulted in silages with the lowest (p < 0.05) fiber contents and highest ether extract and starch contents when compared with control. Thus, MON and essential oils improve fermentative quality but ELO should be used in lower doses in humid silages to avoid negative fermentation impacts. [ABSTRACT FROM AUTHOR]

Mints are aromatic plants of Lamiaceae, globally known for the phytochemical-rich essential oils. Most of the cultivated mints are menthol-rich, whereas spearmint being the only dominant carvone-rich species. In this study, another carvone-rich mint Mentha rotundifolia (L.) Huds., a native of temperate region was assessed for its acclimation in sub-tropical environment to see any possible changes in specialized metabolite accumulation. Plants grown under open environment was compared with glasshouse grown plants where, temperature, humidity and photoperiods were uniformly maintained. Thickened leaves with increased cuticular wax load (2.82 folds) and anthocyanin accumulation (202.97 µg/g) in the widened stems were observed in plants grown in open environment, while higher chlorophyll contents were exhibited by the glasshouse-grown plants. Enhanced antioxidant capacity in open environment, correlated with elevated concentration (86.4% increase for caffeic acid) of wall-bound phenolics was observed. Increased proline, hydrogen peroxide and malondialdehyde contents in open environment indicated the plant's ability to cope up with abiotic stress. Higher amounts of terpenes like (-)-carvone (2.68 folds) and D-limonene (1.35 folds) were found in both internal volatile pool and essential oil of glasshouse-grown plants. Histochemical study of glandular trichomes also supported this finding. In conclusion, glasshouse-grown plants showed relatively better growth and higher terpene contents, nevertheless the plant survived well in warmer environment, with increased antioxidant capacities and phenolic contents. Future study includes mass propagation of this species in different geographical locations with distinct climatic variations to determine the suitable sub-tropical locations for cultivation as a potential alternative to spearmint for commercial-scale (-)-carvone production. [ABSTRACT FROM AUTHOR]

Plantar fasciitis is the most common cause of heel pain in adults with an overall prevalence of 0.85% in the adult population of the US, affecting over 2 million adults annually. Most current treatment modalities are not supported by sufficient evidence to recommend one particular strategy over another. Topical application of analgesics for soft tissue pain is well established, however the plantar fascia presents challenges in this regard due to thick skin, fibrotic tissue, and an often thickened fat pad. Sixty-two patients with plantar fasciitis were randomized to a placebo controlled trial testing the efficacy of a topical solution of plant terpenes containing camphor, menthol, eugenol, eucalyptol, and vanillin. Skin permeation of the mixture was enhanced with 15% dimethylsulfoxide (DMSO), 1% limonene, and rosemary oil. One ml of solution was applied topically twice daily, and pain scores evaluated on Day 0, Day 1, Day 3, and Day 10. Using the validated foot function index 78.1% of patients reported an 85% or greater decrease in their total pain score by day 10 while placebo treatment was without effect (One Way ANOVA, P < 0.01). This study adapts the treatment modality of topical analgesia for soft tissue pain to a problematic area of the body and shows therapeutic promise. ClinicalTrials.gov Identifier: NCT05467631 [ABSTRACT FROM AUTHOR]

Copyright of Science & Technology of Food Industry is the property of Science & Technology of Food Industry Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

This study was conducted to determine the sea fennel essential oil (SFEO) yield, composition, and antioxidant activity of leaves, stem, inflorescences, and umbels from seeds of wild sea fennel (SF) (Crithmum maritimum L.) from the Montenegro coast. The chemical composition of isolated essential oil was determined by GC/MS and GC/FID analyses. The antioxidant activity was determined using the DPPH assay. The maximum SFEO yield was found in umbels with seeds (4.77 mL/100 g p.m.). The leaves contained less EO (0.52 mL/100 g p.m.) than immature inflorescence (0.83 mL/100 g p.m.) The minimum EO content was found in the stem (0.08%). Twenty components were isolated from SFEO leaves, twenty-four from inflorescence, thirty-four components from the stem, and twenty-one components from umbels with seeds. Limonene (62.4–72.0%), γ-terpinene (9.5–14.0%), α-pinene (1.4–5.8%), and sabinene (1–6.5%) were found to be the main components of the SFEO from monoterpene hydrocarbons as dominant grouped components (86% to 98.1%). SF plant parts showed differences in chemical profiles, especially in specific and low-represented ingredients. (E)-anethole (4.4%), fenchone (0.5%), and trans-carveol (0.2%) were present only in umbel with seeds, while the β-longipipene (0.5%), (E)-caryophyllene (0.5%), and (2E)-decenal (0.2%) were found only in the stems. The degree of DPPH radical neutralization increased with incubation time. The SFEO isolated from the stems showed stronger antioxidant activity during the incubation times of 20 and 40 min (EC50 value of 5.30 mg/mL and 5.04 mg/mL, respectively) in comparison to the SFEO isolated from the other plant parts. The lowest antioxidant activity was obtained with the SFEO leaves (155.25 mg/mL and 58.30 mg/mL, respectively). This study indicates that SFEO possesses significant antioxidant activities and is animportant component in the food and pharmaceutical industries. It is important to preserve the existing gene pool and biodiversity with rational use SF for the extraction of high-quality essential oils. [ABSTRACT FROM AUTHOR]

Background: Limonene has a variety of applications in the foods, cosmetics, pharmaceuticals, biomaterials, and biofuels industries. In order to meet the growing demand for sustainable production of limonene at industry scale, it is essential to find an alternative production system to traditional plant extraction. A promising and eco-friendly alternative is the use of microbes as cell factories for the synthesis of limonene. Results: In this study, the oleaginous yeast Yarrowia lipolytica has been engineered to produce d- and l-limonene. Four target genes, l- or d-LS (limonene synthase), HMG (HMG-CoA reductase), ERG20 (geranyl diphosphate synthase), and NDPS1 (neryl diphosphate) were expressed individually or fused together to find the optimal combination for higher limonene production. The strain expressing HMGR and the fusion protein ERG20-LS was the best limonene producer and, therefore, selected for further improvement. By increasing the expression of target genes and optimizing initial OD, 29.4 mg/L of l-limonene and 24.8 mg/L of d-limonene were obtained. We also studied whether peroxisomal compartmentalization of the synthesis pathway was beneficial for limonene production. The introduction of d-LS and ERG20 within the peroxisome improved limonene titers over cytosolic expression. Then, the entire MVA pathway was targeted to the peroxisome to improve precursor supply, which increased d-limonene production to 47.8 mg/L. Finally, through the optimization of fermentation conditions, d-limonene production titer reached 69.3 mg/L. Conclusions: In this work, Y. lipolytica was successfully engineered to produce limonene. Our results showed that higher production of limonene was achieved when the synthesis pathway was targeted to the peroxisome, which indicates that this organelle can favor the bioproduction of terpenes in yeasts. This study opens new avenues for the efficient synthesis of valuable monoterpenes in Y. lipolytica. [ABSTRACT FROM AUTHOR]

The sterile insect technique (SIT) is used for the management of tephritid fruit fly pests. The South American fruit fly, Anastrepha fraterculus (Wiedemann) (Diptera: Tephritidae), is one potential pest to be targeted by means of SIT. The success of SIT depends, to a large extent, on the sexual performance of sterile males. Various approaches have been evaluated with the aim of improving their sexual performance. These include the exposure to plant‐derived compounds and/or the provision of protein sources in the adults' diet capable of stimulating male mating success. The present study aimed to determine whether exposure to volatiles of Citrus limon (L.) Burm. F. (Rutaceae) essential oil and limonene confers a mating advantage to A. fraterculus laboratory males fed two distinct dietary regimes when competing with wild males for wild females under field cage conditions. Dietary regimes were, one, with non‐hydrolysed brewer's yeast and sugar (1:3 ratio), and the other with brewer's yeast hydrolysate enzymatic and sugar (1:12 ratio). The effect was evaluated in four variables associated with mating success: number of copulas obtained, latency to mate, copula duration, and copula location. Exposure to volatiles did not affect the number of matings achieved, irrespective of the diet given to the males. When laboratory males were fed with brewer's yeast hydrolysate, the effect of volatile exposure was shown in latency to mate, copula duration, and copula location. When the laboratory males were fed with non‐hydrolysed brewer's yeast, the effect of volatile exposure was shown only in copula duration. Laboratory males fed brewer's yeast hydrolysate achieved the same number of matings as wild males, whereas laboratory males fed non‐hydrolysed brewer's yeast had lower performance. [ABSTRACT FROM AUTHOR]

Detecting volatile organic compounds (VOCs) emitted from different plant species and their organs can provide valuable information about plant health and environmental factors that affect them. For example, limonene emission can be a biomarker to monitor plant health and detect stress. Traditional methods for VOC detection encounter challenges, prompting the proposal of novel approaches. In this study, we proposed integrating electrospinning, molecular imprinting, and conductive nanofibers to fabricate limonene sensors. In detail, polyvinylpyrrolidone (PVP) and polyacrylic acid (PAA) served here as fiber and cavity formers, respectively, with multiwalled carbon nanotubes (MWCNT) enhancing conductivity. We developed one-step monolithic molecularly imprinted fibers, where S(−)-limonene was the target molecule, using an electrospinning technique. The functional cavities were fixed using the UV curing method, followed by a target molecule washing. This procedure enabled the creation of recognition sites for limonene within the nanofiber matrix, enhancing sensor performance and streamlining manufacturing. Humidity was crucial for sensor working, with optimal conditions at about 50% RH. The sensors rapidly responded to S(−)-limonene, reaching a plateau within 200 s. Enhancing fiber density improved sensor performance, resulting in a lower limit of detection (LOD) of 137 ppb. However, excessive fiber density decreased accessibility to active sites, thus reducing sensitivity. Remarkably, the thinnest mat on the fibrous sensors created provided the highest selectivity to limonene (Selectivity Index: 72%) compared with other VOCs, such as EtOH (used as a solvent in nanofiber development), aromatic compounds (toluene), and two other monoterpenes (α-pinene and linalool) with similar structures. These findings underscored the potential of the proposed integrated approach for selective VOC detection in applications such as precision agriculture and environmental monitoring. [ABSTRACT FROM AUTHOR]

Following a request from the European Commission, EFSA was asked to deliver a scientific opinion on the safety and efficacy of an essential oil obtained from the fruit of Apium graveolens L. (celery seed oil), when used as a sensory additive in feed and water for drinking for all animal species. The EFSA Panel on Additives and Products or Substances used in Animal Feed (FEEDAP) Panel concluded that the use of celery seed oil is of no concern up to the following concentrations in complete feed: 1.6 mg/kg for chickens for fattening, 2.3 mg/kg for laying hens, 2.1 mg/kg for turkeys for fattening, 2.8 mg/kg for piglets, 3.3 mg/kg for pigs for fattening, 4.1 mg/kg for sows, 6.5 mg/kg for veal calves (milk replacer), 6.2 mg/kg for cattle for fattening, sheep, goats and horses, 4.0 mg/kg for dairy cows, 2.5 mg/kg for rabbits, 6.8 mg/kg for salmonids and 7.2 mg/kg for dogs. These conclusions were extrapolated to other physiologically related species. For cats, ornamental fish and other species, no conclusion can be drawn. The use of celery seed oil in animals feed is not expected to pose concern for the consumers and for the environment. The additive under assessment should be considered as an irritant to skin and eyes, and as a respiratory and skin sensitiser. When handling the essential oil, exposure of unprotected users to perillaldehyde and bergapten may occur. Therefore, to reduce the risk, the exposure of the users should be minimised. Since A. graveolens and its preparations were recognised to flavour food and its function in feed would be essentially the same as that in food, no further demonstration of efficacy was considered necessary. [ABSTRACT FROM AUTHOR]

Adenosine-5'-triphosphate (ATP), the primary energy currency in cellular processes, drives metabolic activities and biosynthesis. Despite its importance, understanding intracellular ATP dynamics' impact on bioproduction and exploiting it for enhanced bioproduction remains largely unexplored. Here, we harness an ATP biosensor to dissect ATP dynamics across different growth phases and carbon sources in multiple microbial strains. We find transient ATP accumulations during the transition from exponential to stationary growth phases in various conditions, coinciding with fatty acid (FA) and polyhydroxyalkanoate (PHA) production in Escherichia coli and Pseudomonas putida, respectively. We identify carbon sources (acetate for E. coli, oleate for P. putida) that elevate steady-state ATP levels and boost FA and PHA production. Moreover, we employ ATP dynamics as a diagnostic tool to assess metabolic burden, revealing bottlenecks that limit limonene bioproduction. Our results not only elucidate the relationship between ATP dynamics and bioproduction but also showcase its value in enhancing bioproduction in various microbial species. ATP dynamics influence bioproduction yet are largely unexplored in this context. Here, authors unravel ATP dynamics across various conditions, identify carbon sources which boost ATP levels and bioproduction, and uncover metabolic bottlenecks, shedding light on how ATP dynamics can be used to enhance bioproduction. [ABSTRACT FROM AUTHOR]

This study evaluated the chemical composition and anti-proliferative activity of essential oils (EOs) obtained by hydrodistillation from seven medicinal plants from Cachicadán, La Libertad Región, Perú. Limonene (0.64 to 44.43%) and linalool (0.36 to 2.12%) were identified in all EOs by gas chromatography coupled to mass spectrometry analysis. The major components (relative intensity ≥ 10%) were cis-dihydro carvone, carvone, and cis-piperitone epoxide for Minthostachys mollis leaves; β-pinene, limonene, and ledol for Lepechinia heteromorpha leaves; limonene, neral, and geranial for Aloysia citriodora, both leaves and flowers; α-pinene, and limonene for Myrcianthes myrsinoides leaves; and α-pinene, β-myrcene, and (E)-β-Ocimene for Dalea carthagenensis leaves. Constituted by (Z)-β-ocimene, dihydrotagetone, (Z)-tagetone, and car-3-en-2-one, EO of Tagetes minuta leaves induced an irreversible cytostatic effect against MCF-7 human breast tumor cells. Further in vivo studies must be carried out to establish the safe and efficient dose of T. minuta EO as adjuvant treatment in oncological therapies. [ABSTRACT FROM AUTHOR]

The present study is devoted to evaluate in vitro the chemical composition and the antioxidant and antibacterial properties of essential oils (Eo) extracted by hydrodistillation (HD) and microwave (MW) from the plant peels of Citrus sinensis. The extraction provided yields of 0.26% and 0.02%, respectively. The essential oils were analyzed by GC–MS whose major component is limonene that has a remarkable percentage (78.192% and 58.6%, respectively) for the essential oil extracted by HD and MW. The results of the antioxidant potential were noticeable in each of the essential oils with a higher priority to that extracted by hydrodistillation. The evaluation of the antioxidant power by the free radical scavenging method (DPPH) showed that the essential oils studied have good antioxidant activity, especially for the oil extracted by HD having presented an IC50 of (13.07 ± 0.169) mg/ml, while BHT and ascorbic acid showed very potent and effective anti-free radical activity with IC50 of the order of (19.54 ± 0.32) µg/ml and (1.17 ± 0.05) µg/ml respectively. According to the β-carotene/linoleic acid test, the oxidation of β-carotene was effectively inhibited by the two essential oils of Citrus sinensis peels with a percentage of inhibition of (56.46 ± 0.76) % and (31.39 ± 1.49) % respectively for HD and MW. Eo extracted by HD is more active than ascorbic acid (15.43%). In the antibacterial test, the activity was evaluated by the disc-diffusion method, the two types of sweet orange essential oils inhibited the growth of five bacterial strains out of six: The best activity was obtained against E. coli, Listeria monocytogenes, and Agrobacterium with a diameter of the zone of inhibition between 70 and 84 mm, with the exception of the strain of Bacillus subtilis, there is no zone of inhibition has been observed. [ABSTRACT FROM AUTHOR]

In the era of ecology and careful care for the environment, it becomes important to use renewable raw materials of plant origin, which are often more easily available and cheaper. One of the important and rapidly developing directions of research are works related to the use of waste plant biomass; an example of this trend is the production of activated carbons from food industry waste. One of the examples of the application of derived from biomass activated carbons can be using them as catalysts for the isomerization of terpene compounds. Carbons based on waste biomass are characterized by the minimal amount of waste formation during their manufacture, and their use in the isomerization reaction allows to obtain high conversion of organic raw material and high selectivities of transformation to the desired products, making these carbons environmentally friendly substitutes for the catalysts used usually in this process. In this work, obtained carbonaceous catalysts were tested in the process of isomerization of α-pinene to high value chemicals (mainly camphene and limonene). Under the most favorable conditions (activated carbon from sunflower husks content in reaction mixture 5 wt%, temperature 180 °C, and reaction time 100 min), α-pinene was completely converted (conversion 100 mol%) with high selectivity towards camphene (54 mol%). To prepare activated carbons, biomass precursors (orange peels, sunflower husks, spent coffee grounds) were activated with 85% H3PO4 through the chemical activation. The obtained materials were characterized by such methods as sorption N2 at − 196 °C, X-ray diffraction (XRD), Fourier-transform infrared spectroscopy (FTIR), scanning electron microscope (SEM), and X-ray fluorescence (XRF) to determine the relationship between their textural-chemical properties and catalysts activity in isomerization process. The synthesized materials were characterized by a specific surface area in the range of 930–1764 m2, total pore volume in the range of 0.551–1.02 cm3/g, and total acid-site concentrations in the range of 1.47–2.33 mmol/g. These results showed that textural parameters of the obtained activated carbons have the important role in the isomerization of α-pinene. [ABSTRACT FROM AUTHOR]

Terpenoids have extensive pharmacological activities and are extensively applied in the pharmaceutical, cosmetic, and food industries. Increasing the structural diversity of terpenoids would expand their potential applications. Noncanonical backbones can be generated by coexpressing the canonical mevalonate pathway and C-methyltransferases, or the lepidopteran mevalonate pathway, in engineered strains. The design and chemical synthesis of farnesyl pyrophosphate analogs to create unnatural terpenoids promises two advantages: it complements other methods of terpene synthesis and bypasses the task of engineering entire metabolic pathways to produce alternative substrates in vivo. The artificial metalloenzyme Ir(Me)-porphyrin IX CYP119 allows cyclopropanation of limonene to synthesize high titers of unnatural products with high diastereoselectivity. Terpenoids display chemical and structural diversities as well as important biological activities. Despite their extreme variability, the range of these structures is limited by the scope of natural products that canonically derive from interconvertible five-carbon (C5) isoprene units. New approaches have recently been developed to expand their structural diversity. This review systematically explores the combinatorial biosynthesis of noncanonical building blocks via the coexpression of the canonical mevalonate (MVA) pathway and C-methyltransferases (C-MTs), or by using the lepidopteran mevalonate (LMVA) pathway. Unnatural terpenoids can be created from farnesyl diphosphate (FPP) analogs by chemobiological synthesis and terpene cyclopropanation by artificial metalloenzymes (ArMs). Advanced technologies to accelerate terpene biosynthesis are discussed. This review provides a valuable reference for increasing the diversity of valuable terpenoids and their derivatives, as well as for expanding their potential applications. [ABSTRACT FROM AUTHOR]

Terpenoids are defense metabolites that are induced upon infection or wounding. However, their role in systemic‐induced resistance (SIR) is not known. Here, we explored the role of terpenoids in this phenomenon at a very early stage in the interaction between Austrian pine and the tip blight and canker pathogen Diplodia pinea. We induced Austrian pine saplings by either wounding or inoculating the lower stems with D. pinea. The seedlings were then challenged after 12 h, 72 h, or 10 days with D. pinea on the stem 15 cm above the induction. Lesion lengths and terpenoids were quantified at both induction and challenge locations. Key terpenoids were assayed for antifungal activity in in vitro bioassays. SIR increased with time and was correlated with the inducibility of several compounds. α‐Pinene and a cluster of β‐pinene, limonene, benzaldehyde, dodecanol, and n‐dodecyl acrylate were positively correlated with SIR and were fungistatic in vitro, while other compounds were negatively correlated with SIR and appeared to serve as a carbon source for D. pinea. This study shows that, overall, terpenoids are involved in SIR in this system, but their role is nuanced, depending on the type of induction and time of incubation. We hypothesize that some, such as α‐pinene, could serve in SIR signaling. Summary statement: Trees can resist recurring pathogenic attacks using memory of successful prior encounters with pest or pathogens. Here we show that pathogenic induction results in systemic and selective accumulation of certain terpenoids and other non‐terpenoids in trees conferring higher resistance against newer infection. [ABSTRACT FROM AUTHOR]

The goal of this work was to investigate the chemical composition of Aloysia citriodora essential oil and its biological activities as antioxidant, antibacterial, antifungal and anti-inflammatory potentials depending on the collection region. The highest essential oil yields were in Gabes and Kairouan at the Arid bioclimatic zone. Sixty volatile compounds were identified by GC-FID-MS. The major compounds were limonene and spathulenol in Gabes at the Middle Arid. However, (E)-citral (known as geranial) was the major compound of Belli and Kairouan belonging to the Upper Semi-Arid and Upper Arid areas, respectively. The essential oil extracted from the inferior sub-humid bioclimatic zone (Boussalem) had spathulenol and caryophyllene oxide as predominant components. Inversely to DPPH and ABTS, the antioxidant activities using reducing power assay of A. citriodora essential oils significantly increased from the inferior sub-humid (Boussalem) to the Upper Arid (Kairouan) bioclimatic areas. Independently of region, A. citriodora essential oil exhibited an interesting antibacterial, antifungal and anti-inflammatory potential. [ABSTRACT FROM AUTHOR]