Search Results (396)

Background: Phoebe zhennan and Phoebe chekiangensis are valuable evergreen trees recognized for their unique aromas and ecological significance, yet the organ-related distribution and functional implications of aroma-active volatiles remain insufficiently characterized. Methods: In this study, we applied an integrated GC-MS-based volatile metabolomics approach combined with a relative odor activity value (rOAV) analysis to comprehensively profile and compare the volatile metabolite landscape in the seeds and leaves of both species. Results: In total, 1666 volatile compounds were putatively identified, of which 540 were inferred as key aroma-active contributors based on the rOAV analysis. A multivariate statistical analysis revealed clear tissue-related separation: the seeds were enriched in sweet, floral, and fruity volatiles, whereas the leaves contained higher levels of green leaf volatiles and terpenoids associated with ecological defense. KEGG pathway enrichment indicated that terpenoid backbone and phenylpropanoid biosynthesis pathways played major roles in shaping these divergent profiles. A Venn diagram analysis further uncovered core and unique volatiles underlying species and tissue specificity. Conclusions: These insights provide an integrated reference for understanding tissue-divergent volatile profiles in Phoebe species and offer a basis for fragrance-oriented selection, ecological trait evaluation, and the sustainable utilization of organ-related metabolic characteristics in breeding and conservation programs. Full article

The parasitoid wasp Dolichogenidea gelechiidivoris is a key koinobiont solitary endoparasitoid of the invasive agricultural pest Tuta absoluta. This study investigates both the morphological and molecular foundations of sex-specific olfactory differentiation in this species. Morphological analysis revealed that males possess significantly longer antennae (2880.8 ± 20.36 μm) than females (2137.23 ± 43.47 μm), demonstrating pronounced sexual dimorphism. Scanning electron microscopy identified similar sensilla types on both sexes, but differences existed in the length and diameter of specific sensilla. Transcriptomic analysis of adult antennae uncovered molecular differentiation, identifying 11 odorant-binding proteins (OBPs) and 20 odorant receptors (ORs), with 27 chemosensory genes upregulated in females and 4 enriched in males. Integrating morphological and molecular evidence demonstrates complementary sexual specialization in the olfactory apparatus of D. gelechiidivoris. Linking these findings to the potential functions of different sensilla types, as discussed in the context of prior research, provides crucial insights into the sex-specific use of volatile cues. These findings provide critical insights into the use of volatile signals in this highly relevant species for biological control targeting T. absoluta. Full article

Food quality and safety are essential for ensuring public health, preventing foodborne illness, reducing food waste, maintaining consumer confidence, and supporting regulatory compliance and international trade. This has led to the emergence of many research works that focus on automating and streamlining the assessment of food quality. Electronic noses have become of paramount importance in this context. We analyze the current state of research in the development of electronic noses for food quality and safety. We examined research papers published in three different scientific databases in the last decade, leading to a comprehensive review of the field. Our review found that most of the efforts use portable, low-cost electronic noses, coupled with pattern recognition algorithms, for evaluating the quality levels in certain well-defined food classes, reaching accuracies exceeding 90% in most cases. Despite these encouraging results, key challenges remain, particularly in diversifying the sensor response across complex substances, improving odor differentiation, compensating for sensor drift, and ensuring real-world reliability. These limitations indicate that a complete device mimicking the flexibility and selectivity of the human olfactory system is not yet available. To address these gaps, our review recommends solutions such as the adoption of adaptive machine learning models to reduce calibration needs and enhance drift resilience and the implementation of standardized protocols for data acquisition and model validation. We introduce benchmark comparisons and a future roadmap for electronic noses that demonstrate their potential to evolve from controlled studies to scalable industrial applications. In doing so, this review aims not only to assess the state of the field but also to support its transition toward more robust, interpretable, and field-ready electronic nose technologies. Full article

The flavor characteristics, perception, and molecular mechanisms of eight menthol isomers were investigated by sensory analysis combined with computational simulations. The sensory analysis results show significant differences in the odor profiles of the different menthol isomers. Among them, L-menthol shows a pleasant, sweet, and mint-like odor with a distinct freshness and no off-flavors, whereas the remaining seven isomers were interspersed with negative odors (musty, herbal, or earthy aromas). L-menthol and D-menthol had the lowest detection thresholds of 5.166 and 4.734 mg/L, respectively. The molecular docking results of the menthol isomers with olfactory receptors (Olfr874, OR8B8, and OR8B12) indicate that hydrogen bonding and hydrophobic interactions were the key binding forces. The binding energy ranged from −7.3 to −5.1 kcal/mol. Residues His-55 (Olfr874), Thr-56 (Olfr874), Leu-55 (OR8B8), Tyr-94 (OR8B8), Thr-57 (OR8B8), Phe-199 (OR8B12), and Ser-248 (OR8B12) with high frequencies particularly contributed to the recognition of menthol isomers. These findings contribute to a deeper understanding of the olfactory perception mechanism of menthol and provide data support for the development and precise application of minty odorants. Full article

The characteristics and complexity of Baijiu are inseparable from the promotion of aging. While the impact of compounds such as alcohols, esters, and acids on the aroma of aged Baijiu has been extensively studied, the role of other trace compounds in the aging process should not be overlooked. To further investigate the relationship between volatile compounds and the aging of Nongxiangxing Baijiu, sensomics research methods were employed to analyze profiles of young and aged Nongxiangxing Baijiu. In this study, a total of 94 aroma compounds were analyzed in both young and aged Nongxiangxing Baijiu by GC-O/MS. Among these, 12 aroma compounds significantly associated with the aging process were identified by quantification and odor activity values (OAVs). Furthermore, the omission tests result showed that 4-methyl-2-methoxyphenol (2066.79 μg/L), benzaldehyde (3860.30 μg/L), β-phenylethanol (5638.85 μg/L), 3-(methylsulfanyl)propan-1-ol (8.82 μg/L), 3-(methylsulfanyl)propanal (15.91 μg/L), and linalool (17.36 μg/L) were key aroma compounds of aged Nongxiangxing Baijiu. This study reveals that trace compounds contribute to the distinct aroma complexity of aged Nongxiangxing Baijiu, providing a foundation to support aging process analysis. Full article

Zeugodacus cucuribitae (Coquillett) (Z. cucuribitae) is a global extremely invasive quarantine pest which has a wide host range of fruits and vegetables. At present, there are a few control measures for Z. cucuribitae, and deltamethrin and avermectin are commonly used. Among the hosts of Z. cucuribitae, Luffa acutangular, Luffa cylindrica, Sechium edule, Brassica oleracea var. botrytis, Musa nana, and Fragaria × ananassa are non-favored hosts. However, it is still not clear why these hosts are non-favored and whether there are any repellent components of Z. cucuribitae in these hosts. In this study, the components of these six hosts were collected from the literature, and the genes of odor and chemical sensation were determined from the genome of Z. cucuribitae. After the potential relationships between these components and genes were determined by molecular docking methods, the KEGG and GO enrichment analysis of these genes was conducted, and a complex network of genes vs. components vs. Kegg pathway vs. GO terms was constructed and used to select the key components for experiments. The results show that oleanolic acid (1 mg/mL, 0.1 mg/mL, and 0.01 mg/mL), rotenone (1 mg/mL, 0.1 mg/mL, and 0.01 mg/mL), and beta-caryophyllene oxide (1 mg/mL, 0.1 mg/mL, and 0.01 mg/mL) had a significant repellent effect on Z. cucuribitae, and three components, rotenone (1 mg/mL and 0.1 mg/mL), echinocystic acid (1 mg/mL, 0.1 mg/mL, and 0.01 mg/mL), and beta-caryophyllene oxide (1 mg/mL, and 0.1 mg/mL) had significant stomach toxicity in Z. cucuribitae. Furthermore, a complex signaling pathway was built and used to predict the effect of these components on Z. cucuribitae. These components probably play roles in the neuroactive ligand–receptor interaction (ko04080) and calcium signaling (ko04020) pathways. This study provides a reference for the prevention and control of Z. cucuribitae and a scientific reference for the rapid screening and development of new pest control drugs. Full article

This study aimed to investigate phytoplankton dynamics and water quality at three drinking water intakes (Duchang, Hukou, and Xingzi) in Poyang Lake through monthly monitoring from May 2023 to April 2024. The results showed that a total of 168 species of phytoplankton were identified in nine phyla, and there were significant spatial and temporal differences in the abundance of phytoplankton at the three waterworks intakes, with a spatial trend of annual mean values of Duchang > Xingzi > Hukou and a seasonal trend of summer and autumn > spring and winter. The dominant species of phytoplankton in the waterworks intakes of the three waterworks also showed obvious spatial and temporal differences. Cyanobacteria (particularly Pseudanabaena sp. and Microcystis sp.) dominated the phytoplankton communities during summer and autumn, demonstrating significant water degradation potential. In contrast, Cyclotella sp. prevailed in winter and spring assemblages. Based on water quality assessments at the three intake sites, the Duchang County intake exhibited year-round mild eutrophication with persistent mild cyanobacterial blooms (June–October), while the other two sites maintained no obvious bloom conditions. Further analyzing the toxic/odor-producing algal strains, the numbers of dominant species of Pseudanabaena sp. and Microcystis sp. in June–October in Duchang County both exceeded 1.0 × 10⁷ cells·L⁻¹. It is necessary to focus on their release of ATX-a (ichthyotoxin-a), 2MIB (2-Methylisoborneol), MCs (microcystins), etc., to ensure the safety of the water supply at the intake. Building upon these findings, we propose a generalized algal monitoring framework, encompassing three operational pillars: (1) key monitoring area identification, (2) high-risk period determination, and (3) harmful algal warnings. Each of these is substantiated by our empirical observations in Poyang Lake. Full article

Red goji berries, reputed worldwide as “superfruit”, are commonly marketed after natural drying or hot-air drying. A sensomics approach was applied to the aroma analysis of red goji berries under two drying methods. Fifty-two aroma-active compounds were screened and identified by aroma extract dilution analysis (AEDA) coupled with gas chromatography with olfactometry (GC/O). The contents and the odor activity values (OAVs) of 49 aroma-active compounds were determined. Acetic acid was the predominant aroma compounds in both berries. Meanwhile, the key aroma compounds in both berries were (E)-2-nonenal, (Z)-4-heptenal, 3-methyl-2,4-nonanedione, hexanal, etc., which were lipid derivatives. Natural drying promoted the formation of some aldehydes that exhibited green and fatty notes. Hot-air drying facilitated the production of ketones with hay-like and cooked apple-like odor attributes due to the thermal reaction. The fatty acid patterns between naturally dried and hot-air-dried red goji berries differed not significantly and were dominated by linoleic acid, oleic acid, palmitic acid, etc. The knowledge of the impacts of different drying processes on the aroma quality in red goji berries is beneficial for the quality control and optimization of dried red goji berries. Full article

Cat owners are involved in their cats’ healthcare, including the prevention of parasitic diseases. However, a comprehensive understanding of their preferences for feline antiparasitics is lacking. This study addresses this gap through a multifaceted methodology comprising three phases. In Phase 1, the physical properties and usability aspects of seven topical antiparasitic formulations were assessed. Within Phase 2, an ease-of-use study was conducted to evaluate the cat owners’ application experience with deidentified products representing three topical antiparasitics. Phase 3 included the identification and validation of product attributes most valued by pet owners through interviews with cat owners and veterinary experts. The product attributes identified informed the subsequent quantitative discrete choice experiment (DCE), which involved 1040 cat owners from different countries (Australia/New Zealand, Canada, Greece/Spain, and the UK) and aimed to analyze their preferences based on choices among product profiles mirroring four topical antiparasitics: selamectin–sarolaner, moxidectin–fluralaner, moxidectin–imidacloprid, and eprinomectin–esafoxolaner–praziquantel. Phase 1 showed that the selamectin–sarolaner formulation exhibits minimal odor, less stickiness, and less drying time. The ease-of-use study (Phase 2) showed that the blinded product representing the selamectin–sarolaner formulation was characterized by seamless application, rapid dispensing, and a sense of control during application. The quantitative DCE study (Phase 3) indicated a preference for the product profile mirroring the selamectin–sarolaner formulation among a global sample of cat owners. Demographic characteristics such as gender, age, and insurance status influenced their preferences. Key predictors for preferring the selamectin–sarolaner formulation over at least one comparator treatment included the ability to confirm successful administration, age restrictions, ease of application, and the time before the cat could sit on furniture following administration. These findings suggest that cat owners prioritize ease of use, safety, and overall user experience, providing valuable guidance for veterinary practitioners to make informed treatment recommendations. Full article

Traditional smoking techniques, while historically valued for preservation and flavor enhancement, face limitations in aromatic diversity and safety, prompting exploration of spice-derived alternatives to meet modern culinary demands. This study explores the volatile compound profiles and aroma modulation of chicken wings smoked with four spices—cardamom, rosemary, mint, and rose—using a novel, household-friendly smoking protocol. The method combines air fryer pre-cooking (180 °C, 16 min) with electric griddle-based smoke infusion, followed by HS-SPME/GC-TOF/MS, relative odor activity value (ROAV) calculations, and metabolomic analysis. A total of 314 volatile compounds were identified across five samples. Among them, 45 compounds demonstrated odor activity values (ROAV) ≥ 1, contributing to green, woody, floral, and sweet aroma attributes. Eucalyptol displayed the highest ROAV (2543), underscoring its dominant sensory impact. Metabolomic profiling revealed a general upregulation of differential volatiles post-smoking: terpenes were enriched in wings smoked with cardamom, rosemary, and mint, while aldehydes and alcohols predominated in rose-smoked samples. An integrated screening based on ROAV and metabolomic data identified 24 key volatiles, including eucalyptol, β-myrcene, methanethiol, and α-pinene, which collectively defined the aroma signatures of spice-smoked wings. Spice-specific aroma enrichment and sensory properties were evident: rosemary intensified woody–spicy notes, mint enhanced herbal freshness, and rose amplified floral attributes. The proposed method demonstrated advantages in safety, ease of use, and flavor customization, aligning with clean-label trends and supporting innovation in home-based culinary practices. Moreover, it facilitates the tailored modulation of smoked meat flavor profiles, thereby enhancing product differentiation and broadening consumer acceptance. Full article

The tomato leaf miner, Tuta absoluta (Lepidoptera: Gelechiidae), is a destructive pest of Solanaceae crops worldwide. Its olfactory system plays an important role in locating mating partners and recognizing host plants. Understanding its olfactory recognition mechanism, particularly the function of odorant-binding proteins (OBPs), may reveal potential targets for pest management. In this study, we characterized two antenna-specific OBPs, TabsOBP45 and TabsOBP46, which were identified from the T. absoluta genome. Sequence analysis revealed that both TabsOBPs belong to the classic OBP subfamily, which is characterized by the presence of six conserved cysteine residues and an N-terminal signal peptide. Both TabsOBPs showed predominant antennal expression in quantitative real-time PCR (qRT-PCR) assays, suggesting their key roles in olfactory perception. Fluorescence competitive binding assays with a total of 63 tested volatiles revealed that 13 compounds exhibited strong binding affinities (Ki < 22 µM) to TabsOBP45, with the highest binding affinity to β-ionone, β-caryophyllene, terpinolene, and cinnamaldehyde. Nine compounds showed strong binding affinities to TabsOBP46, with the strongest binding to 4-anisaldehyde, 4-methoxybenzaldehyde, cinnamaldehyde, and β-ionone. Molecular docking analysis revealed the key residues involved in β-ionone binding: TabsOBP45 interacted with ILE8, ALA9, PHE12, TRP37, ILE92, PHE94, THR115, and PHE118, while TabsOBP46 interacted with ILE8, PHE12, PHE36, TRP37, ILE92, LEU94, PHE118, and VAL134. These results provide new insights into the olfactory mechanism of T. absoluta and potential molecular targets for the development of olfactory-based pest control strategies. Full article

The aroma of fermented milk products is a key determinant of consumer preference. This study investigates the impact of different lactic acid strains on the aroma characteristics of fermented milk, identifies key volatile compounds, and establishes odor molecule labels to guide strain selection and modification. Sensory evaluation, dynamic headspace sampling (DHS), and gas chromatography olfactometry–mass spectrometry (GC-O-MS) were used to analyze 23 milk samples prepared with various lactic acid bacteria strains. A total of 74 volatile compounds were identified by GC-O-MS. Fermented milk P4 had the highest total volatile compound content (1566.50 ng/g). Flavor profiles were found to depend on strain metabolism rather than specific genera, with fermentation flavor quality enhanced by strains containing 2,3-butanedione, acetic acid, and sulfur compounds. Four distinct flavor clusters were established through molecular labels. These results provide targeted guidance for industrial strain selection and modification in fermented milk production, enhancing sensory appeal and consumer acceptance. Full article

Mung bean (Vigna radiata L.) is globally cultivated and has been widely used in the food industries. Other than nutrients, the composition of the volatile organic compounds (VOCs) often influences the quality of mung bean-based products. However, the dynamics of VOCs and the flavor changes during mung bean seed development remain unexplored. This study investigated the VOC and flavor composition in four mung bean varieties by integrating relative odor activity value (ROAV) evaluation and transcriptomic analysis. A total of 65 VOCs were identified, with eucalyptol serving as a key maturity indicator in LL655 and SH-1, while nonanal contributed significantly to the characteristic beany flavor across all varieties. Transcriptomic analysis revealed four downregulated geranylgeranyl diphosphate synthase genes during seed development, leading to terpenoid accumulation patterns. Terpenoids, including trans-beta ocimene and gamma-terpinene, appeared to be regulated by transcription factors (TFs) from the RLK-Pelle, WRKY, AP2/ERF, bHLH, and bZIP families. Additionally, two MYB TFs showed potential roles in modulating the accumulation of phenylpropanoid/benzenoid derivatives. This study provides a comprehensive understanding of the VOC accumulation and flavor variation during mung bean seed development, enriches the knowledge of flavor chemistry in mung bean varieties, and facilitates a theoretical foundation for optimizing and developing mung bean-based products. Full article

Wuyi Shuixian tea, a premium oolong tea known for its complex floral-fruity aroma, exhibits significant quality variations across different grades. This study systematically analyzed the aroma characteristics and key fragrant compounds of four grades (Grand Prize SA, First Prize SB, Outstanding Award SC, and Non-award SD) using headspace solid-phase microextraction-gas chromatography-mass spectrometry (HS-SPME-GC-MS), odor activity value (OAV) analysis, and multivariate statistical methods. A total of 159 volatile compounds were identified, with similar compound categories but distinct concentration gradients between grades. OAV-splitting analysis (based on OAV ≥ 1 as the threshold for aroma activity) identified β-ionone (fruity), octanal (fatty), and linalool (floral) as core aroma-active contributors, as their OAV values significantly exceeded 10 in awarded grades (SA, SB, SC), indicating dominant roles in sensory perception. Notably, linalool, a floral marker, showed a concentration gradient (SA > SB > SC) and was absent in SD, serving as a critical determinant of grade differentiation. Orthogonal partial least squares-discriminant analysis (OPLS-DA) further distinguished awarded grades (SA, SB, SC) by balanced fruity, floral, and woody notes, while SD lacked floral traits and exhibited burnt aromas. This classification was supported by hierarchical clustering analysis (HCA) of volatile profiles and principal component analysis (PCA). Electronic nose data validated these findings, showing strong correlations between sensor responses (W5S/W2W) and key compounds like hexanal and β-ionone. This study elucidates the molecular basis of aroma-driven quality grading in Wuyi Shuixian tea, providing a scientific framework for optimizing processing techniques and enhancing quality evaluation standards. The integration of chemical profiling with sensory attributes advances precision in tea industry practices, bridging traditional grading with objective analytical metrics. Full article

Herbivore-induced plant volatiles (HIPVs) play a pivotal role in mediating tritrophic interactions between plants, herbivores, and their natural enemies. Paracarophenax alternatus, a parasitic mite targeting the egg stage of Monochamus alternatus, has emerged as a promising biocontrol agent. However, its ability to detect Pinus massoniana-derived HIPVs for host insect localization remains unclear. G-protein-coupled receptors (GPCRs) may play a role in mediating the perception of HIPVs and associated chemosensory signaling pathways in mites. In this study, a total of 85 GPCRs were identified from P. alternatus. All GPCRs exhibited conserved transmembrane domains and stage-specific expression patterns, with 21 receptors significantly upregulated in viviparous mites. Combined with two previously identified odorant receptors (ORs), six candidate chemosensory receptors were selected for molecular dynamics simulations to validate their binding stability with key volatile compounds. The results demonstrate that specific GPCRs likely facilitate HIPV detection in mites, enabling precise host localization within dynamic ecological niches. Our findings provide critical insights into the molecular basis of mite–host interactions and establish a framework for optimizing P. alternatus-based biocontrol strategies against pine wilt disease vectors. Full article