Odor Research Articles

Effects of the Molecular Structure of Malodor Substances and Their Masking on 1,2-Dioleoyl-sn-glycero-3-phosphocholine Molecular Layers.

Certain odors have been shown not only to cause health problems and stress but also to affect skin barrier function. Therefore, it is important to understand olfactory masking to develop effective fragrances to mask malodors. However, olfaction and olfactory masking mechanisms are not yet fully understood. To understand the mechanism of the masking effect that has been studied, the responses of several target substance (TS) molecules-1,2-dioleoyl-sn-glycero-3-phosphocholine (DOPC) mixed molecular layers to odorant (OD) molecules were examined as a simple experimental model of epithelial cellular membranes injured by TS molecules. Here, we examined trans-2-nonenal, 1-nonanal, trans-2-decenal, and 1-decanal as TS molecules to clarify the effects of double bonds and hydrocarbon chain lengths on the phospholipid molecular layer. In addition, benzaldehyde and cyclohexanecarboxaldehyde were utilized as OD molecules to clarify the masking effect of the aromatic ring. Surface pressure (Π)-area (A) isotherms were measured to clarify the adsorption or desorption of TS and OD molecules on the DOPC molecular layer. In addition, Fourier transform infrared spectroscopy was performed to clarify the interactions among DOPC, TS, and OD molecules. We found that TS molecules with and without double bonds had different effects on the DOPC molecular layer and that molecules with shorter chain lengths had greater effects on the DOPC molecular layer. Furthermore, OD molecules with aromatic rings counteracted the effects of the TS molecules. On the basis of this research, not only a detailed mechanism by which odor molecules affect lipid membranes without mediating olfactory receptors is elucidated but also more effective OD molecules with masking effects are proposed.

Olfactory and gustatory receptor genes in fig wasps: Evolutionary insights from comparative studies

The mechanisms of chemoreception in fig wasps (Hymenoptera, Agaonidae) are of primary importance in their co-evolutionary relationship with the fig trees they pollinate. We used transcriptome sequences of 25 fig wasps in six genera that allowed a comparative approach to the evolution of key molecular components of fig wasp chemoreception: their odorant (OR) and gustatory (GR) receptor genes. In total, we identified 311 ORs and 47 GRs, with each species recording from 5 to 30 OR genes and 1–4 GR genes. 304 OR genes clustered into 18 orthologous groups known to be sensitive to cuticular hydrocarbons (CHC), pheromones, acids, alcohols and a variety of floral scents such as cineole, Linalool, and Heptanone. 45 GR genes clustered into 4 orthologous groups that contain sweet, bitter, CO2 and undocumented receptors. Gene sequences in most orthologous groups varied greatly among species, except for ORco (60.0% conserved) and sweet receptors (30.7% conserved). Strong purifying selection of both odorant and gustatory genes was detected, as shown by low ω values. Signatures of positive selection were detected in loci from both OR and GR orthologous groups. Fig wasps have relatively few olfactory and especially gustatory receptors, reflecting the natural history of the system. Amino acid sequences nonetheless vary significantly between species and are consistent with the phylogenetic relationships among fig wasps. The differences in ORs within some orthologous groups from the same species, but different hosts and from closely related species from one host can reach as low as 49.3% and 9.8% respectively, implying the ORs of fig wasps can evolve rapidly to novel ecological environments. Our results provide a starting point for understanding the molecular basis of the chemosensory systems of fig wasps.

Genome-Wide Analysis of Odorant and Gustatory Receptors in Six Papilio Butterflies (Lepidoptera: Papilionidae).

Simple SummaryThe butterflies of the Lepidoptera are representatives of herbivorous insects. Host plant diversities may shape the evolution of chemosensory receptors in butterflies. However, little is known about whether the host plant range is correlated with the size differences of chemoreceptors as key molecular targets for butterfly–plant chemical interactions. Here, we characterized 381 odorant (ORs) and 328 gustatory (GRs) receptors in one Papilio generalist and five other Papilio specialists regarding their comprehensive annotation, gene structure, phylogenetics and expression profiles. Among six Papilio species, orthologous ORs or GRs shared conserved gene structure, but the differences in intron size frequencies were observed between the generalist and the specialists. Furthermore, expression profiles identified candidate OR and GR genes in antennae, foretarsi or reproductive tissues of P. xuthus. This study addresses, for the first time, the issue that the breath of host plants does not appear to result in the obvious expansions of ORs and GRs in Papilio butterflies and identifies candidate molecular targets associated with olfaction, oviposition or reproduction in P. xuthus.The chemical interactions of insects and host plants are shaping the evolution of chemosensory receptor gene families. However, the correlation between host range and chemoreceptor gene repertoire sizes is still elusive in Papilionidae. Here, we addressed the issue of whether host plant diversities are correlated with the expansions of odorant (ORs) or gustatory (GRs) receptors in six Papilio butterflies. By combining genomics, transcriptomics and bioinformatics approaches, 381 ORs and 328 GRs were annotated in the genomes of a generalist P. glaucus and five specialists, P. xuthus, P. polytes, P. memnon, P. machaon and P. dardanus. Orthologous ORs or GRs in Papilio had highly conserved gene structure. Five Papilio specialists exhibited a similar frequency of intron lengths for ORs or GRs, but which was different from those in the generalist. Phylogenetic analysis revealed 60 orthologous OR groups, 45 of which shared one-to-one relationships. Such a single gene in each butterfly also occurred in 26 GR groups. Intriguingly, bitter GRs had fewer introns than other GRs and clustered into a large clade. Focusing on the two chemoreceptor gene families in P. xuthus, most PxutORs (52/58) were expressed in antennae and 31 genes in reproductive tissues. Eleven out of 28 foretarsus-expressed PxutGRs were female-biased genes, as strong candidates for sensing oviposition stimulants. These results indicate that the host range may not shape the large-scale expansions of ORs and GRs in Papilio butterflies and identify important molecular targets involved in olfaction, oviposition or reproduction in P. xuthus.

Biological and Chemical Atmospheric Emissions of the Biogas Industry

Actions of French governments on waste, resource and energy management force to focus on waste treatment and recovery process. Among these processes, anaerobic digestor offers significant advantages compared to other forms of waste treatment. It permits an organic waste treatment and a double valorization. The organic waste treatment enables the production of a digestate and a combustible gas fraction called biogas. The digestate, is an improved fertilizer, and can be enhanced by spreading or composting. Biogas can be valorized to produce heat or electricity. From this activity sector, energy production is expected to increase from 1,478 GWh in 2005 to 13,701 GWh in 2020 (Club Biogas ATEE, 2011). Anaerobic digestion is widely studied to understand its mechanisms at microbial level and to improve biogas production and process stability. However, health risk for workers in these facilities and for surrounding residents is very poorly documented. Gaseous and particulate emissions are also incompletely defined. Information on odor concentrations and biogas chemical /biological composition has been investigated. Nevertheless, no data on emissions from inputs storage locations or digestate was currently available. The EMAMET project aims to improve our understanding concerning the biogas production sector. Sources of gaseous and bioaerosol emissions will be researched and characterized on the whole production chain. The chemical composition of gaseous emissions will be completed by odor concentration determination. Biological emissions will be determined by molecular methods. From this information, specific biological and/or chemical indicators of this activity will be defined. In addition, 2D and 3D emission modeling will used to determine the influence zone of the biogas production implantation. To confirm this influence area a research of biological and microbial indicators around a pilot site will be realized. These data can help to assess health and environmental risks for workers and surrounding populations. This information is necessary to develop relevant sensors for control and monitoring of such emerging energetic processes.

Understanding relationships among MHC, microbes, and odor: a comment on Schubert et al.

Understanding relationships among MHC, microbes, and odor: a comment on Schubert et al.

Considering birds to understand the interplay of MHC, microbiota, and odor: a comment on Schubert et al.

Considering birds to understand the interplay of MHC, microbiota, and odor: a comment on Schubert et al.

A deep dive into MHC-related odors: a comment on Schubert et al.

A deep dive into MHC-related odors: a comment on Schubert et al.

Screening for effective odors through which Conopomorpha sinensis Bradley (Lepidoptera: Gracillariidae) locates its host

Screening for effective odors through which Conopomorpha sinensis Bradley (Lepidoptera: Gracillariidae) locates its host

Rapid degeneration of Drosophila olfactory neurons in Orco mutant maxillary palps.

Drosophila melanogaster vinegar flies have two olfactory organs: the antenna and maxillary palp. Olfactory neurons in these tissues respond to odorants via odorant receptors. Insect odorant receptors are heterotetramers of two proteins: an odorant binding OrX subunit and an Odorant Receptor Co-Receptor (Orco). Mutation of Orco disrupts odorant receptor formation, and abolishes olfactory responses. Some antennal olfactory neurons in Orco mutants have been previously shown to degenerate. Here, we examine if maxillary palp olfactory neurons also degenerate in Orco mutants. We find degeneration occurs both more broadly and more rapidly in Orco mutant maxillary palp olfactory neurons than reported for antennae, with ~60% of all mutant olfactory neurons absent in maxillary palps by 7 days post eclosion. Interestingly, the subset of Orco mutant olfactory neurons that express the Or42a receptor appear resistant to degeneration. These results suggest the maxillary palp might be a suitable model for examining the molecular mechanisms underlying neurodegeneration in sensory neurons.

The scent of life: Celebrating the career and life of Jocélia Grazia (Table of contents)

The scent of life: Celebrating the career and life of Jocélia Grazia (Table of contents)

The scent of life: Celebrating the career and life of Jocélia Grazia (Cover)

The scent of life: Celebrating the career and life of Jocélia Grazia (Cover)

Functional morphology of the tongue of lizard Salvator merianae (Reptilia: Squamata)

The reptilian tongue has morphological and functional variations according to the feeding mechanisms and habitat of the species. This study aimed to understand the morphofunctional characteristics of the tongue of the lizard Salvator merianae , through anatomical, histological and scanning electron microscopy analyses. This experiment used five adult animals, which were collected in the municipality of Vicosa, Minas Gerais, from Brasil. The tongue of S. merianae was protractile and bifid, important to detect odors and locate prey, strongly muscular and with keratinized and pigmented stratified epithelium for protection. Mucous secretion was present as an important tool for lubrication and protection in view of the protrability of the tongue and the great presence of bacteria. Morphological specificities of the S. merianae tongue reflect its direct participation in feeding, with squamiform papillae for food apprehension. Taste buds were not found, which excludes the tongue participation in the taste.

Oligotrophic/Eutrophic Dynamics in the Potable Water of Hilly Area of Champawat (India)

In the present investigation, the physicochemical and microbiological properties of water in the hilly area of Champawat district Uttarakhand, India in pre-monsoon season of 2017 were studies. For the study, the variation of parameters was recorded in natural sources of water and their corresponding supply water. The analysis was carried out for the parameters like Colour, Odour, Turbidity, pH, Temperature, TDS, EC, Total Hardness, Total Alkalinity, Cl-, F-, SO42-, NO3-, PO43-, Total coli and E. coli. In the study, 3 the pH was found to be slightly alkaline, the high value of Turbidity was observed in few sites and some analysed samples were also contaminated by total coliform and E. coli. By comparing the studied parameters, the result showed minor differences between the parameters of source water and supply water. The study concluded that either the value of physicochemical parameters falls under the permissible limits of WHO and BIS, but some sampling sites are microbial contamination was observed.

Tratamento da osteonecrose dos maxilares associada ao uso de medicamentos - revisão de literatura

Introdução: A osteonecrose dos maxilares associada ao uso de medicamentos é uma doença que se dá pelo uso de terapias com drogas antirreabsortivas, como bisfosfonatos e Denosumab, ou antiangiogênicos. Embora a manifestação desta doença não tenha alta incidência, sua ocorrência gera um impacto significativo na vida do paciente, levando à sintomatologia dolorosa, com supuração e odor fétido. Apesar dos vários tratamentos empregados, não existe um consenso acerca da maior eficácia de um tratamento frente a outro. Assim, este trabalho objetiva demonstrar as diferentes modalidades de tratamento e os benefícios aliados a cada uma. Materiais e Métodos: Buscas feitas na base de dados PubMed/MEDLINE sobre o tema Osteonecrose dos Maxilares Associada ao Uso de Medicamentos, aliado a operadores boleanos, durante os meses Maio, Junho e Julho de 2020. Resultados: A pesquisa resultou em 143 artigos e, após a aplicação dos critérios de elegibilidade, 49 foram selecionados (23 estudos prospectivos, 17 retrospectivos e 9 séries de caso), englobando 2617 pacientes e 2848 lesões. Os tratamentos foram divididos em 5 modalidades (terapias adjuvantes, tratamentos cirúrgicos agressivos, terapias teciduais, tratamento assistido por medicamentos e terapias cirúrgicas conservadoras).Conclusão: Vários tratamentos são propostos e parece claro que as cirurgias agressivas são as terapias com melhores resultados, sobretudo quando aliadas a uma terapia tecidual ou adjuvante. As cirurgias conservadoras apresentam papel importante, principalmente, em pacientes portadores de condições sistêmicas que contraindiquem as cirurgias maiores.

Formulation and Characterization of Nanostructured Lipid Carrier Encapsulate Lemongrass Oil Using Ultrasonication Technique

Lemongrass with scientific name Cymbopogon citratrus was widely found in tropical country. The aroma scent released by the lemongrass able to relieve anxiety and rejuvenate us. Lemongrass oil is suitable to use as one of the car freshener ingredient. However, the oil is easily evaporating when expose to high temperature environment. In order to preserve the fragrance release, the objective of this study is to formulate the nanostructured lipid carrier (NLC) encapsulated lemongrass oil using the ultrasonication technique. The characterization of the NLC-Lemongrass were particle size, polydispersity index (PDI), zeta potential, efficiency of the loading and the release rate. The NLC-Lemongrass oil formulation had an average mean particle size of 43.86 nm, PDI of 0.28, zeta potential -42.9 mV and efficiency of the loading 82.13 %, respectively. In addition, after 25 d, the component of the lemongrass oil inside the NLC able to remain at 53.24 %. Therefore, the NLC was successfully encapsulate the lemongrass oil and prolong the aroma release at high temperature environment.

Chemoreceptor Diversity in Apoid Wasps and Its Reduction during the Evolution of the Pollen-Collecting Lifestyle of Bees (Hymenoptera: Apoidea)

Chemoreceptors help insects to interact with their environment, to detect and assess food sources and oviposition sites, and to aid in intra- and interspecific communication. In Hymenoptera, species of eusocial lineages possess large chemoreceptor gene repertoires compared with solitary species, possibly because of their additional need to recognize nest-mates and caste. However, a critical piece of information missing so far has been the size of chemoreceptor gene repertoires of solitary apoid wasps. Apoid wasps are a paraphyletic group of almost exclusively solitary Hymenoptera phylogenetically positioned between ant and bee, both of which include eusocial species. We report the chemosensory-related gene repertoire sizes of three apoid wasps: Ampulex compressa, Cerceris arenaria, and Psenulus fuscipennis. We annotated genes encoding odorant (ORs), gustatory, and ionotropic receptors and chemosensory soluble proteins and odorant-binding proteins in transcriptomes of chemosensory tissues of the above three species and in early draft genomes of two species, A. compressa and C. arenaria. Our analyses revealed that apoid wasps possess larger OR repertoires than any bee lineage, that the last common ancestor of Apoidea possessed a considerably larger OR repertoire (∼160) than previously estimated (73), and that the expansion of OR genes in eusocial bees was less extensive than previously assumed. Intriguingly, the evolution of pollen-collecting behavior in the stem lineage of bees was associated with a notable loss of OR gene diversity. Thus, our results support the view that herbivorous Hymenoptera tend to possess smaller OR repertoires than carnivorous, parasitoid, or kleptoparasitic species.

Research progress on odor binding proteins and odor receptors of mosquitoes

Research progress on odor binding proteins and odor receptors of mosquitoes

Scent as motivational muse

A whiff to inspire workouts As an unpredictable year ends, many of us still turn to a predictable resolution for the new year: to get more exercise. But what if your sense of smell could move you t...

Scent as a motivational muse

Scent as a motivational muse

Efforts to Explore and Convey the Appeal of Scents

Efforts to Explore and Convey the Appeal of Scents