Search Results (184)

The increasing demand for sustainable materials has propelled the development of bio-based elastomers derived from renewable terpenes. This study presents the synthesis of high-cis poly(butadiene-co-terpene) copolymers using coordination chain transfer polymerization with neodymium-based catalysts, enabling precise control of molecular weight and microstructure. Two terpene monomers, β-myrcene and trans-β-farnesene, were incorporated up to 45 wt% without compromising the elastomeric 1,4-cis polybutadiene segments. The copolymers were evaluated as impact modifiers in acrylonitrile–butadiene–styrene (ABS) and as vulcanizable rubber formulations. ABS containing bio-based copolymers exhibited distinct rubber morphologies, including elongated and rod-like particles with average particle diameters greater than 1042 nm and rubber phase volume fraction values ≥ 0.49, resulting in improved impact resistance exceeding 580 J/m and elongation at break higher than 12%. Vulcanized rubbers incorporating terpene segments displayed tunable curing kinetics, mechanical properties, and dynamic mechanical behavior, with notable increases in elongation (up to ~520%) and elasticity attributed to lower crosslink density (<1.20 × 10⁻⁴ mol/mL). Additionally, its energy dissipation capacity has been enhanced compared to the high-cis polybutadiene. These findings highlight the potential of terpene-derived bioelastomers as sustainable alternatives to fossil-based rubbers, offering comparable or enhanced performance for engineering polymer applications. The study underscores important structure–property relationships, providing a foundation for further optimization toward industrial adoption. Full article

Gongora is a neotropical epiphytic orchid found from Mexico to South America, with 11 species recorded in Brazil. Little is known about the aromas produced by the flowers of these orchid species. This study aimed to identify the volatile constituents of the flowers of Gongora histrionica (1), G. jauariensis (1), G. longiracemosa (2), G. minax (1), and G. pleiochroma (2), all of which are found in the Amazon. Gas chromatography-mass spectrometry (GC-MS) was used to analyze the volatile constituents of Gongora. Additionally, multivariate statistical analysis was employed to evaluate the variability of volatile constituents in their floral aromas. The principal constituents (>25%) of Gongora specimens were (Z)-α-bisabolene, terpinen-4-ol, cis-β-elemenone, (E,E)-geranyl linalool, β-bisabolene, (E,E)-α-farnesene, and 1,8-cineole. Based on the identified compounds, the multivariate statistical analysis revealed seven distinct groups for the Gongora volatile concentrates, indicating a significant variability between the studied species. These results contribute to a better understanding of the genus Gongora chemotaxonomy analysis. Full article

Apolygus lucorum is one of the main pests affecting tea quality. Chemical control is the primary method for managing this pest, but issues such as pesticide residues and the development of resistance are inevitable. The pest’s extensive host range holds significant practical implications for developing novel food baits. This study first investigated the preference of adult A. lucorum for tea branches under different conditions and various host plants by using the Y-tube olfactometer. Subsequently, the trapping efficacy of active tea volatile components and food baits was tested. The results revealed that adult A. lucorum exhibited a stronger preference for healthy and mechanically damaged tea branches, while they avoided branches infested with high densities of conspecifics. Adult A. lucorum showed significantly higher selection rates for Gossypium hirsutum, Vigna radiata leaf, Glycine max leaf, Phaseolus vulgaris, Lablab purpureus, and Brassica pekinensis compared with healthy tea branches. In field trials, three tea volatile baits showed effective trapping performance, (E,E)-α-farnesene, nonanal, and (Z)-3-hexenol. Three mixture baits of foods and tea plant volatiles, B. pekinensis + (Z)-3-hexenol, P. vulgaris + (E,E)-α-farnesene, and S. melongena + (Z)-3-hexenol, not only demonstrated high attractiveness but also maintained a residual effect period as long as 20 days. This study provides new insights and approaches for the integrated management of A. lucorum and offers technical support for the development of novel green pest control technologies in tea plantations. Full article

Orange spiny whitefly (Aleurocanthus spiniferus Quaintance) is a major pest with economic significance to tea plants, as both nymphs and adults suck plant sap and contribute to the development of tea sooty mold. The occurrence of this pest varies considerably among different tea cultivars, even within the same plantation. This study aims to characterize the bioactive constituents of tea volatiles mediating A. spiniferus host selection, and leverage these semiochemicals to develop effective field trapping systems. Through field investigations and Y-tube olfactometer tests, we identified two highly preferred tea cultivars (‘Huangjinya’ and ‘Fuding white tea’) and two cultivars (‘Baiye No. 1’ and ‘Longjing 43’) that were not preferred. Behavioral assays and gas chromatography-mass spectrometry (GC-MS) analysis revealed four attractive compounds [hexanol, (E)-2-hexenal, linalool, and (E,E)-α-farnesene] and two repellent compounds [nonanal and (Z)-3-hexenol] in the volatile emissions of the four cultivars. A hexane solution (10 µL) of nonanol, (Z)-3-hexenol, linalool, and (E,E)-α-farnesene at a concentration of 100 µg/µL was able to elicit an obvious electrophysiological (EAG) response. In field trials, the synergistic bait trap equipped with two types of attractants, 500 µL of hexane solution of the mixture of linalool and (E,E)-α-farnesene (3:1, v/v), and the mixture of linalool and (Z)-3-hexenol (3:1, v/v) at the concentration of 100 μg/μL, showed significantly higher attractant efficacy and selectivity. Overall, this study indicates that tea volatiles play a crucial role in the host selection of A. spiniferus, and the synthetic mixtures of tea volatiles have the potential to be developed as commercial plant-based attractants for adult A. spiniferus. This study contributes to the development of sustainable, environmentally friendly management strategies for a pest that is challenging to prevent and control. Full article

We have recently described a murine model of vaginal secretion that allows the measurement of minute changes in vaginal secretion. Using this model, we determined that female mice experience a vaginal secretory response to the scent of males, a response regulated by circadian and estrous factors since females did not respond during their sleep phase, nor when in metestrus. Female mice can distinguish the social status of a male by scent cues and show a preference for the scent of dominant males. We therefore tested whether or not vaginal responses to male scent differ by the social status of that male. Vaginal secretory responses were measured using a recently described method employing a colorimetric thread. In addition, while we have shown that the proposed female attractant α/β farnesenes evoked a strong vaginal response in female mice, a second volatile preputial gland-derived messenger, 1-hexadecanol, has also been proposed to serve as a female attractant. Here we test whether or not 1-hexadecanol similarly stimulates a vaginal secretory response. We now report that the female vaginal secretory response differs according to the social status of the male: the urine-borne scent of dominant males elicited a vaginal response, while samples from non-dominant males did not. In related odor-preference tests we confirmed that female mice spend more time investigating the urine scent of dominant males. We additionally tested whether or not a second putative female attractant 1-hexadecanol would elicit a vaginal secretory response. Like the α/β farnesenes, 1-hexadecanol is volatile, derived from preputial glands, and induces an investigatory response in females. However female mice did not experience a vaginal secretory response to the scent of 1-hexadecanol. We did confirm that females spent more time investigating hexadecanol over vehicle, indicating that there can be a disconnect between behavioral measures of interest and a vaginal preparatory response. In summary, we find that subordinate male mice do not elicit a vaginal secretory response, indicating that male social status impacts the physiological responses of females to the prospect of coitus. We additionally find that in contrast to farnesenes, the putative female attractant 1-hexadecanol does not elicit a vaginal response. These findings underscore the potential value of this murine model and indicate that even in mice, vaginal responses are under complex regulation. Full article

For the first time, essential oils (EOs) from the leaves and flowers of Lantana camara L., grown in Loja, Ecuador, have been isolated by steam distillation and analyzed. The oil yields from the extractions were 0.021 and 0.005% for the leaves and flowers, respectively. A compositional analysis using gas chromatography revealed the presence of EOs, comprising approximately 97.98% of the extract from the leaves and 74.58% of the extract from the flowers. The chemical characterization of these EOs indicated sesquiterpenic profiles. The most representative constituents of the essential oils from the flowers were γ-Curcumene (21.79%), (E, E)-α-Farnesene (20.07%), and α-Zingiberene (13.38%), while the EOs from the leaves were characterized by the abundant presence of γ-Curcumene (21.87%), (E)-Nerolidol (15.09%), and cis-Muurola-4(14),5-diene (12.65%). Furthermore, the acaricidal efficacy of the EOs from the leaves of L. camara was tested by a dip test with adult ticks, resulting in acaricidal efficacy at concentrations of 10%, demonstrating the useful properties of these EOs. Full article

To date, various species of Erigeron genus have been used both in the ethnopharmacology of numerous nations across the world and in contemporary herbal practices. The objective of this study is to revise the phytochemical data on the essential oils (EOs) of various fleabanes species and to evaluate the variability of their biological activities. Up to June 2025, this review provides an updated overview of 105 literature sources (published during last 25 years) related to 14 Erigeron sp. (native, naturalized, or invasive) which have been investigated extensively and are of the greatest significance. It summarizes the compositional variability of the EOs and their pharmacological and toxic effects, such as anti-inflammatory, anticancer, antiproliferative, skin regeneration, antioxidant, antifungal, antibacterial, insecticidal, larvicidal, repellent, and allelopathic activity. The EOs of each Erigeron species were characterized, and a chemical structure of 43 major constituents is presented herein. The most characteristic and prevalent compounds were found to be limonene, δ-3-carene, matricaria ester, lachnophyllum ester, germacrene D, β-caryophyllene, β-farnesene, α-bergamotene, allo-aromadendrene, etc., in the EOs from the E. acris, E. annuus, E. bonariensis, E. canadensis, E. floribundus E. mucronatus, and E. speciosus plants. Major constituents, such as borneol, bornyl acetate, modhephen-8-β-ol, cis-arteannuic alcohol, β-caryophyllene, and τ-cadinol, were found in the oils of E. graveolens (Inula graveolens). A paucity of data concerning E. incanus EOs was revealed, with the prevalence of 3-hydroxy-4-methoxy cinammic acid and thymol acetate noted in the oils. The EOs from E. multiradiatus and E. sublyratus were comprised mainly of matricaria and lachnophyllum esters. The available data on EOs of E. ramosus is limited, but the main constituents are known to be α-humulene, 1,8-cineole, eugenol, and globulol. The EOs containing appreciable amounts of matricaria and lachnophyllum esters exhibited strong anticancer, anti-inflammatory, antimicrobial, larvicidal, and repellent activities. Repellence is also related to borneol, bornyl acetate, caryophyllene derivatives, τ-cadinol, modhephen-8-β-ol, and cis-arteannuic alcohol. Cytotoxicity was determined due to the presence of limonene, δ-3-carene, α- and β-farnesene, (E)-β-ocimene, ledene oxide, sesquiphellandrene, and dendrolasin in the fleabanes EOs. Skin regeneration and antifungal properties were related to germacrene D; and anti-inflammatory effects were determined due to high amounts of limonene (E)-β-ocimene, lachnophyllum ester, and germacrene D. The antimicrobial properties of the oils were conditioned by appreciable quantities of limonene, β-pinene, 1,8-cineole, carvacrol, thymol acetae, β-eudesmol, 2,6,7,7α-tetrahydro-1,5-dimethyl-1H-indene-3-carboxaldehyde, caryophyllene and its oxide, allo-aromadendrene, α-humulene, farnesene, carvacrol, and eugenol. This review provides a foundation for further studies on volatile secondary metabolites to explore the potential sources of new biologically active compounds in Erigeron sp. Full article

Vibrational spectroscopy, including Raman and near-infrared techniques, enables the non-destructive evaluation of starch gelatinization, head rice yield, and aroma-active volatile compounds in parboiled rice subjected to varying soaking and drying conditions. Raman and NIR spectra were collected for rice samples processed under different conditions and integrated with reference analyses to develop and validate partial least squares regression and artificial neural network models. The optimized PLSR model demonstrated strong predictive performance, with R² values of 0.9406 and 0.9365 for SG and HRY, respectively, and residual predictive deviations of 3.98 and 3.75 using Raman effective wavelengths. ANN models reached R² values of 0.97 for both SG and HRY, with RPDs exceeding 4.2 using NIR effective wavelengths. In the aroma compound analysis, p-Cymene exhibited the highest predictive accuracy, with R² values of 0.9916 for calibration, and 0.9814 for cross-validation. Other volatiles, such as 1-Octen-3-ol, nonanal, benzaldehyde, and limonene, demonstrated high predictive reliability (R² ≥ 0.93; RPD > 3.0). Conversely, farnesene, menthol, and menthone showed poor predictability (R² < 0.15; RPD < 0.4). Principal component analysis revealed that the first principal component explained 90% of the total variance in the Raman dataset and 71% in the NIR dataset. Hotelling’s T² analysis identifies influential outliers and enhances model robustness. Optimal processing conditions for achieving maximum HRY and SG values were determined at 65 °C soaking for 180 min, followed by drying at 70 °C. This study underscores the potential of integrating vibrational spectroscopy with machine learning techniques and targeted wavelength selection for the high-throughput, accurate, and scalable quality evaluation of parboiled rice. Full article

In this study, we analyzed the essential oils (EOs) extracted by steam distillation from the leaves and flowers of Parthenium hysterophorus L., grown in three different locations in southern Ecuador: Espíndola (ESP), Loja (LOJ) and Quilanga (QUI). Approximately 97.45%, 98.27% and 95.99% of the oil constituents were identified using gas chromatography–mass spectrometry (GC-MS) and gas chromatography–flame ionization detection (GC-FID). Sesquiterpene hydrocarbons were predominant in the EOs. The most representative constituents of the sample from ESP were germacrene D (35.08%), myrcene (11.32%), (E)-β-ocimene (10.21%), (E)-caryophyllene (7.90%), germacra-4(15),5,10(14)-trien-1-α-ol (5.18%) and (E, E)-α-farnesene (4.99%), with an AChE IC₅₀ of 14.78 and with 16.38 and 93.16 µg/mL from ABTS and DPPH, respectively. The EOs from LOJ were characterized by the abundant presence of germacrene D (28.30%), myrcene (13.95%), (E)-β-ocimene (10.51%) and isolongifolan-7-α-ol (8.26%), with an AChE IC₅₀ of 16.65 and with 36.18 and 158.43 µg/mL from ABTS and DPPH, respectively. Finally, the EOs from QUI contained germacrene D (32.20%), myrcene (13.36%), (E)-β-ocimene (8.54%), (E, E)-α-farnesene (6.77%), germacra-4(15),5,10(14)-trien-1-α-ol (5.69%) and (E)-caryophyllene (5.37%), with an AChE IC₅₀ of 10.69 and with 14.50 and 92.98 µg/mL from ABTS and DPPH, respectively. This study identifies chemotypic variation in P. hysterophorus collected from different locations and, for the first time, the AChE inhibitor was evaluated. These findings provide a scientific basis for the clinical application of P. hysterophorus EOs in the future treatment of Alzheimer’s disease. Full article

Chamomile essential oils (EOs) are widely used in cosmetics for their antioxidant, anti-inflammatory, and antimicrobial properties. Bulgaria, with its long-standing tradition in EO production, provides an ideal setting to examine the influence of species and cultivation practices on oil quality. This study compares the chemical composition and biological activity of EOs from German chamomile (Matricaria recutita L.) and Roman chamomile (Chamaemelum nobile L.), sourced from two major Bulgarian producers—Bulgarska Bilka Ltd. and Kateko Ltd. (Plovdiv, Bulgaria). Gas chromatography–mass spectrometry (GC–MS) profiling revealed species- and producer-dependent differences. German chamomile EOs were rich in β-farnesene, chamazulene, and bisabolol oxides, whereas Roman chamomile EOs were dominated by isobutyl angelate and related esters. Antioxidant activity, assessed via the ABTS assay, was higher in German chamomile EOs, especially from Bulgarska Bilka Ltd. The oils also showed photoprotective potential, with SPF values of 26–27 for German and 9–16 for Roman chamomile. Anti-inflammatory activity, evaluated by inhibition of albumin denaturation, was highest in Roman chamomile oils and comparable to that of prednisolone, while German chamomile also showed strong effects. Antimicrobial activity was generally low, with moderate effects observed only against Penicillium chrysogenum and Aspergillus flavus. These findings support the targeted use of chamomile EOs in cosmetics—German chamomile for antioxidant-rich, UV-protective, and microbiome-supportive care, and Roman chamomile for soothing, anti-inflammatory, and fragrance-enhancing applications. Full article

In Africa, the current harmful maize pest is Spodoptera frugiperda. Its attack can be severe and cause total economic losses. Spodoptera eridania is another species of the same genus, detected a few months after S. frugiperda’s outbreaks in West and Central Africa. Though both species share a range of host plants, socioeconomic studies are yet to provide specific figures on the potential impacts of S. eridania. The high and inappropriate application of insecticides to control Spodoptera species has negative effects on the environmental elements’ health. Semiochemical tools are increasingly exploited to design alternative pest management strategies. We hypothesize that host plants release components used by the pests and a shared parasitoid to locate the host. To verify that hypothesis, we conducted behavioral assays and GC-MS analyses to identify the potential chemical signals involved in the communications of the moths and their shared parasitoid C. icipe. The results showed that healthy and herbivory-induced maize and amaranth produced some chemical compounds including α-pinene, limonene, isopentyl acetate, (Z)-beta-farnesene, and methyl dodecanoate, which prospects their potential use in alternative pest management strategies for recruiting C. icipe to control these pests. Further work will focus on field validation to develop an alternative control strategy for the moths. Full article

Aroma is an important processing and consumption quality trait of fruits and vegetables, and terpenes produced from the terpenoid metabolic pathway are a critical component of chili fruit flavor. This pathway involves the participation of at least eighteen enzymes, such as AACT, HMGS, HMGR, MVK, PMK, MVD, FPPS, GGPPS, DXS, DXR, MCT, CMK, MECPS, HDS, HDR, GPPS, IDI, and TPS. In this study, the genome wide information, expression characteristics, and relationship with terpenoids of terpenoid pathway genes are analyzed in C. annuum. The results showed that C. annuum has sixty-seven genes related to terpene metabolic pathways. Non-targeted metabolomics studies found that the content of aromatic terpenoids α-calacorene, α-cubene, and cis-β-farnesene increased with fruit development in HDL fruits, while linalool and nerolidol were much higher in GLD608. Correlation analyses between qRT-PCR and metabolome data showed that the expression levels of CaHMGS-3, CaMVD-1, CaCMK-1, and CaGGPPS-2 were positively correlated with the content of linalool, a flavor monoterpene alcohol. CaMECPS-1 was positively correlated with cis-β-farnesene, and there was also a significant positive regulatory relationship between CaTPS-5 and nerolidol relationship. In conclusion, the present study provides genetic resources for further studies on the gene regulatory mechanisms of flavor synthesis and terpenoid metabolic pathways in chili. Full article

Hop (Humulus lupulus L.) is a crucial ingredient in beer, valued for its bitter acids and essential oils. Traditionally cultivated in temperate regions, hop production faces challenges from climate change, necessitating the exploration of new growing areas. This study evaluated the chemical quality of hop varieties grown in Brazil’s subtropical conditions to assess their suitability for brewing. Seven hop varieties (Cascade, Centennial, Columbus, Chinook, Comet, Fuggle, and Nugget) were analyzed for total α- and β-acids and essential oil composition. Bitter acids were quantified by spectrophotometric analysis, and volatile compounds were identified using gas chromatography coupled to mass spectrometry (GC-MS). Comet exhibited the highest a-acid level (10.54%), indicating strong bittering potential. Essential oil analysis revealed β-myrcene, (E)-caryophyllene, and α-humulene as predominant compounds. Centennial showed a distinct (E)-β-farnesene profile, a characteristic of noble hops. All varieties contained α- and β-selinene, suggesting a common metabolic pattern. The results indicate that Brazil has the potential to produce high-quality hops with suitable chemical profiles for brewing. As traditional hop-growing regions face climate-related challenges, hops cultivated in Brazil may offer a viable alternative for achieving the desired chemical composition required by the brewing industry. Full article

Hop is a key ingredient in beer production, and drying it allows it to be stored before use. Unfortunately, postharvest drying techniques can negatively affect hop quality. In this study, we compared drying using a hot stove (H), freeze-drying (F), and ventilated at room temperature (VRT) drying, focusing on the chemical quality and essential oil composition. To achieve 80% water removal, F and H took two days, while VRT took five days. F and H preserved a high content of total chlorophyll (F 81.89 g/kg dm; H 82.70 g/kg dm) and carotenoids (F 54.02 g/kg dm; H 54.71 g/kg dm). The hop storage index (HSI) increased with all drying techniques, but especially in F and H. The lowest amount of polyphenols was found in the H sample (348.48 g/kg dm), while the highest content was found in VRT (631.11 g/kg dm). Freeze-drying gave the best results, especially in relation to the amount of polyphenols and antioxidant power of the product. Regarding essential oils, in the class of sesquiterpene hydrocarbons, we found α-humulene (F 24.0%; VRT 24.7%; H 25.6%), β-caryophyllene (F 10.5%; VRT 9.4%; H 11.1%), and β-farnesene (F 6.8%; VRT 6.0%; H 7.4%). The total monoterpene hydrocarbon amount increased in the VRT sample. Thus, freeze-drying emerges as an alternative technique to the hot stove; however, the cost is high. Instead, drying at ventilated room temperature represents a sustainable and valid technique for preserving the aromatic characteristics and polyphenols of the product. Full article

Tanacetum cinerariifolium, a perennial Asteraceae plant, is renowned for its ornamental value and natural insecticidal compounds, especially pyrethrins. These compounds, primarily stored in flower heads, are highly effective as insecticides with low toxicity to mammals, making them crucial for organic agriculture, along with the sesquiterpene (E)-β-farnesene (EβF), play critical roles in T. cinerariifolium defense mechanisms. However, the spatiotemporal patterns of these secondary metabolites in stems and flower heads, as well as their regulatory mechanisms, remain unclear. This study investigated the biosynthesis and regulation of pyrethrins and EβF across developmental stages (S1–S4) in flowers and stems using GC-MS and transcriptomics. Transcriptome analysis revealed that the expression of pyrethrin biosynthetic genes was not synchronized with pyrethrin accumulation. The main pyrethrin biosynthetic genes exhibited coordinated expression patterns, peaking during early flowering stages (S1–S2), while pyrethrin accumulation was primarily observed during mid-flower development. In contrast, the biosynthetic genes of EβF showed synchronized expression with EβF accumulation, with the highest activity observed in stems and early flowers. WGCNA identified jasmonic acid signaling, trichome differentiation, and terpene transport pathways as potentially associated with pyrethrin biosynthesis. Hub genes including MYC2 were identified as playing pivotal roles in regulating secondary metabolite biosynthesis. These findings provide new insights into the regulation and biosynthesis of pyrethrins and EβF, offering a foundation for optimizing bioactive compound production and advancing sustainable pest management strategies. Full article