Pleasant Odor Research Articles

Unpleasant odors compared to pleasant ones cause higher cortical activations detectable by fNIRS and observable mostly in females.

Olfactory perception can be studied in deep brain regions at high spatial resolutions with functional magnetic resonance imaging (fMRI), but this is complex and expensive. Electroencephalography (EEG) and functional near-infrared spectroscopy (fNIRS) are limited to cortical responses and lower spatial resolutions but are easier and cheaper to use. Unlike EEG, available fNIRS studies on olfaction are few, limited in scope, and contradictory. Here, we investigated fNIRS efficacy in assessing the hedonic valence of pleasant and unpleasant odors, using ten channels on each hemisphere, covering the orbitofrontal cortex and adjacent areas involved in olfactory and cognitive tasks. Measurements on 22 subjects (11 males and 11 females) showed statistically significant higher increases in oxygenated hemoglobin concentration for the unpleasant odor, compared to the pleasant one (mean difference = 1.025 × 10-1 μM). No difference in activation was found between the hemispheres. Conversely, differences were observed between the sexes: for the first time, we show that higher activations for the unpleasant odor relative to the pleasant one are detectable by fNIRS in females (mean difference = 1.704 × 10-1 μM), but not in an equal-sized and equal-age group of males. Moreover, females had greater activations relative to males for the unpleasant odor (mean difference = 1.285 × 10-1 μM). Therefore, fNIRS can capture peculiarities of olfactory activations, highlighting differences between odors with opposite valence and between sexes. This evidence positions fNIRS next to EEG as suitable technologies for cortical investigations of olfactory perception, providing complementary information (late and early response components, respectively), with lower costs and easier operation (albeit at lower resolutions) compared to fMRI.

INSTRUMENTAL COLOUR, TEXTURE AND SENSORY PROPERTIES OF PLJESKAVICA (TRADITIONAL SERBIAN MEAT PRODUCT) AFFECTED BY ADDITION OF FRESHLY EXTRACTED Allium ursinum L.

Pljeskavica is a traditional Serbian burger-type meat product that is also very popular across the Balkan countries. The use of natural supplements containing various bioactive compounds, such as wild garlic (Allium ursinum L.) extracts, has gained more importance in the last several decades and has promising results for the prevention of the processes leading to detoriation. The present study aimed to evaluate the influence of Allium ursinum L. freshly squeezed extract (FSAULE) on colour, texture and sensory attributes of raw and grilled pljeskavica during cold (10 days) and freeze storage (90 days). Control (CON) and three experimental treatments containing different concentrations of FSAULE were prepared – AUL1 (1.32 mL/kg), AUL2 (4.40 mL/kg) and AUL3 (8.79 mL/kg). Redness and yellowness of raw meat and backfat particles were not altered after the addition of different amounts of FSAULE throughout cold and freeze storage. Meat and backfat particles of raw AUL3 were significantly darker compared to CON and other AULs. The results of texture profile analysis indicate that the addition of different amounts of FSAULE did not alter instrumental texture properties. According to the check-all-that-apply analysis of sensory properties, AUL3 was mostly characterized by affirmative attributes – pleasant odour, taste, saltiness, softness, juiciness and ideal texture. The affirmative attributes that were not present in AULs, but were present in CON, were detected by a small number of consumers – from 2.8% (pleasant colour) to 15.0% (pleasant odour). Most consumers found that intense garlic odour (85.0%) and intense garlic-like taste (83.9%) were not present in either CON or AULs.

Olfactory modulation of visual attention and preference towards congruent food products: An eye tracking study

In multisensory environments, odours often accompany visual stimuli, directing attention towards congruent objects. While previous research shows that people fixate longer on objects that match a recently smelled odour, it remains unclear whether odours directly influence product choices. Since odours persist in real-world settings, we investigated the effects of repeated odour exposure on visual attention and product choice, accounting for potential olfactory habituation. In a within-participant design, 30 participants completed a task where either a lemon odour (experimental condition) or clean air (control) was paired with congruent lemon-based food images, which varied to prevent visual habituation. We measured eye movements and choice preferences for these food products.Results revealed that participants exhibited longer gaze durations and more frequent fixations on food products congruent with the lemon odour. Repeated odour exposure had no effect on gaze patterns, as participants consistently focused on odour-congruent products throughout the experiment. The intensity and pleasantness of the lemon odour remained stable over time, suggesting no olfactory habituation occurred with this food-related odour. Despite this stable visual attention and odour intensity and pleasantness, participants began to diversify their product choices, selecting fewer odour-congruent items over time.These findings suggest that while odours continue to direct attention towards matching products, repeated exposure may reduce their influence on product choice, highlighting the complex role of olfactory stimuli in decision-making. The study provides insights into how odours interact with visual cues and influence consumer behaviour in prolonged exposure scenarios.

Effects of Chlorine Dioxide on the Postharvest Storage Quality of Fresh-Cut Button Mushrooms (Agaricus bisporus)

The application of chlorine dioxide (ClO2) in microbial safety and quality maintenance of fresh produce has received extensive attention. Fresh-cut button mushrooms (Agaricus bisporus) are prone to spoilage, resulting in a short shelf-life. In this study, ClO2 treatment was used to preserve fresh-cut button mushrooms, and its effect on maintaining the postharvest quality was investigated using sensory evaluation, weight loss, color, firmness, respiration rate, electronic-nose (E-nose) analysis and microbial analysis. During the 8 d storage, both the 50 and 100 mg·L−1 ClO2 treatment reduced the aerobic bacteria count on the surface of fresh-cut button mushrooms. However, the results showed that the 50 mg·L−1 ClO2 treatment but not the 100 mg·L−1 ClO2 treatment significantly inhibited the deterioration of comprehensive quality. The 50 mg·L−1 ClO2 treatment maintained the high sensory evaluation and pleasant volatile odor of fresh-cut button mushrooms as well as reduced the decreasing of fresh weight and firmness. Contrary to expectations, the application of ClO2 treatment showed worse appearances in color (lower L*, higher a*, b* and browning index) of fresh-cut button mushrooms. Significant differences were observed between CK and ClO2-treated groups from day 0 to day 6, while there were no significant differences of a*, b* and browning index between CK and the 50 mg·L−1 ClO2 treatment at the end of storage (on day 8). In conclusion, the 50 mg·L−1 ClO2 can maintain the good quality of fresh-cut button mushrooms.

Dynamic evolution of volatile compounds during cold storage of sturgeon fillets analyzed by gas chromatography-ion mobility spectrometry and chemometric methods

This study investigated the changes in quality and volatile flavoring compounds in sturgeon fillets during refrigeration. Potential flavor compounds were identified using orthogonal partial least squares discriminant analysis (OPLS-DA) and gas chromatography– ion mobility spectrometry (GC-IMS). The results showed that TVB-N content, TBARS values, total colony counts, and K-value increased with prolonged refrigeration, reaching spoilage thresholds after approximately eight days. A total of 33 volatile compounds (including monomers and dimers) were detected in sturgeon fillets during different refrigeration periods, including aldehydes, alcohols, ketones, acids, esters, ethers, and other compounds. OPLS-DA further revealed flavor differences in sturgeon fillets across different refrigeration stages, identifying 18 distinct volatile compounds. Correlation analysis showed that trans-2-Pentenal, 2-methylpropanal, and glutaraldehyde were associated with pleasant odor to the frozen sturgeon fillets in the early stage, while hexane nitrile and thiazole were the main substances that caused unpleasant odors.

The human olfactory bulb communicates perceived odor valence to the piriform cortex in the gamma band and receives a refined representation back in the beta band.

A core function of the olfactory system is to determine the valence of odors. In humans, central processing of odor valence perception has been shown to take form already within the olfactory bulb (OB), but the neural mechanisms by which this important information is communicated to, and from, the olfactory cortex (piriform cortex, PC) are not known. To assess communication between the 2 nodes, we simultaneously measured odor-dependent neural activity in the OB and PC from human participants while obtaining trial-by-trial valence ratings. By doing so, we could determine when subjective valence information was communicated, what kind of information was transferred, and how the information was transferred (i.e., in which frequency band). Support vector machine (SVM) learning was used on the coherence spectrum and frequency-resolved Granger causality to identify valence-dependent differences in functional and effective connectivity between the OB and PC. We found that the OB communicates subjective odor valence to the PC in the gamma band shortly after odor onset, while the PC subsequently feeds broader valence-related information back to the OB in the beta band. Decoding accuracy was better for negative than positive valence, suggesting a focus on negative valence. Critically, we replicated these findings in an independent data set using additional odors across a larger perceived valence range. Combined, these results demonstrate that the OB and PC communicate levels of subjective odor pleasantness across multiple frequencies, at specific time points, in a direction-dependent pattern in accordance with a two-stage model of odor processing.

Pleasant Odor Decreases Mouse Anxiety-like Behaviors by Regulating Hippocampal Endocannabinoid Signaling.

Anxiety disorder is one of the most common neuropsychiatric disorders, and affects many people's daily activities. Although the pathogenesis and treatments of anxiety disorder have been studied for several decades, the underlying mechanisms remain elusive. Here, we provide evidence that olfactory stimuli with inhaled linalool or 2-phenylethanol decreased mouse anxiety-like behaviors and increased the activities of hippocampal dentate granule cells (DGCs). RNA-sequencing analysis identified retrograde endocannabinoid signaling, which is a critical pathway for mood regulation and neuron activation, is altered in the hippocampus of both linalool- and 2-phenylethanol-exposed mice. Further studies found that selective inhibition of endocannabinoid signaling by injecting rimonabant abolished the activation of DGCs and the anxiolytic effect induced by linalool or 2-phenylethanol. Together, these results uncovered a novel mechanism by which linalool or 2-phenylethanol decreases mouse anxiety-like behaviors and increases DG activity likely through activating hippocampal retrograde endocannabinoid signaling.

An analysis of the safety of Sevoflurane drugs: A disproportionality analysis based on Food and Drug Administration Adverse Event Reporting System.

Sevoflurane is a volatile anesthetic that can tolerate inhalation induction and is widely used for inducing anesthesia due to its pleasant odor. As a drug that has been on the market for nearly 30 years, the vast majority of adverse reactions have been documented. This study aims to improve the adverse reactions related to Sevoflurane through the mining, organizing and analysis of Food and Drug Administration Adverse Event Reporting System database data. We collected, organized, and analyzed reports from the first quarter of 2004 to the fourth quarter of 2022. We performed disproportionality analysis algorithms, including reporting odds ratio, the proportional reporting ratio values, to quantify the signal values of different adverse events (AEs). A total of 1126 AEs and 27 system organ classes were identified by performing statistics analysis system software. By combining algorithm calculations, we create a forest map of the top 30 AEs of the reporting odds ratio signal. Based on the reviewing relevant literature, we found that the vast majority of AEs have been reported in relevant studies. However, there is currently no study revealing the correlation between atrial fibrillation and Sevoflurane, which means that atrial fibrillation may be an unreported AE of Sevoflurane. In the present study, we found that atrial fibrillation may be a new adverse reaction of Sevoflurane through the Food and Drug Administration Adverse Event Reporting System database, which can function as a novel guideline to guide us in the more standardized use of Sevoflurane in clinical practice.

Alternative splicing of CsbHLH133 regulates geraniol biosynthesis in tea plants.

Geraniol is one of the most abundant aromatic compounds in fresh tea leaves and contributes to the pleasant odor of tea products. Additionally, it functions as an airborne signal that interacts with other members of the ecosystem. To date, the regulation of the geraniol biosynthesis in tea plants remains to be investigated. In this study, a correlation test of the content of geraniol and its glycosides with gene expression data revealed that nudix hydrolase, CsNudix26, and its transcription factor, CsbHLH133 are involved in geraniol biosynthesis. In vitro enzyme assays and metabolic analyses of genetically modified tea plants confirmed that CsNudix26 is responsible for the formation of geraniol. Yeast one-hybrid, dual-luciferase reporter, and EMSA assays were used to verify the binding of CsbHLH133 to the CsNudix26 promoter. Overexpression of CsbHLH133 in tea leaves enhanced CsNudix26 expression and geraniol accumulation, whereas CsbHLH133 silencing reduced CsNudix26 transcript levels and geraniol content. Interestingly, CsbHLH133-AS, produced by alternative splicing, was discovered and proved to be the primary transcript expressed in response to various environmental stresses. Furthermore, geraniol release was found to be affected by various factors that alter the expression patterns of CsbHLH133 and CsbHLH133-AS. Our findings indicate that distinct transcript splicing patterns of CsbHLH133 regulate geraniol biosynthesis in tea plants in response to different regulatory factors.

Beyond Distracted Eating: Cognitive Distraction Downregulates Odor Pleasantness and Interacts with Weight Status.

Considering the widespread issue of distracted eating, our study investigates how cognitive distraction influences the sensory perception of food-related odors among individuals with varying weight statuses. We conducted an exploratory, randomized, and cross-sectional experimental study, using the Tetris game to simulate real-life cognitive distraction, incorporating two distraction levels (low and high) and presenting five distinct odors. A total of 59 participants, categorized into a lean (n = 30) and overweight/obese group (n = 29) based on their body mass index (BMI), received odor stimuli while playing Tetris at low and high difficulty, corresponding to low and high distraction levels, respectively. Participants subsequently rated odor intensity and pleasantness under the two cognitive distraction conditions. Respiratory movements were monitored to ensure accurate olfactory stimulation. Our findings revealed no significant difference in odor intensity ratings across distraction levels (p = 0.903). However, there was a significant reduction in odor pleasantness under high cognitive distraction (p = 0.007), more pronounced in lean participants compared to those with an overweight status (p = 0.035). Additionally, an interaction between gender and cognitive distraction effects was observed in odor pleasantness perception. The differential effects of distraction across weight-status groups and genders are discussed in the context of hedonic motivation and compensatory mechanisms. This study sheds light onto the sensory mechanisms underlying distracted eating and could inform more personalized strategies for promoting healthier eating habits in a world dominated by distractions.

Designing and Characterizing a Multipurpose Facial Scrub Infused with Chrysopogon zizanioides, Prunus dulcis and Santalum album

This study focuses on the design and characterization of a herbal scrub utilizing natural excipients for skincare applications. The primary objective was to develop a safe and effective product capable of addressing common skin issues such as wrinkles, acne, and excessive oil production. The scrub formulation incorporated a blend of carefully selected excipients, including aloevera, amla, coriander, liquorice, sandalwood, lemon peel powder, khus-khus, almond oil, rose petal extract, and black catechu. Various parameters, including physical appearance, viscosity, pH, spreadability, irritability, stability, and microbial assay, were systematically assessed to comprehensively evaluate the scrub. The results revealed that the scrub demonstrated outstanding cooling effects, skin lightening properties, and efficacy in preventing new pimples. It exhibited a pleasant odor, possessed a brown color, and proved non-irritating to the skin. The scrub's texture was smooth, facilitating easy spreading. In conclusion, the formulated herbal scrub emerged as a safe and efficacious exfoliating product, offering the benefits of glowing skin without any adverse effects. Overall, this research contributes valuable insights into the development of a skincare solution that combines natural ingredients for optimal effectiveness and user satisfaction.

Effects of Inoculation with Koji and Strain Exiguobacterium profundum FELA1 on the Taste, Flavor, and Bacterial Community of Rapidly Fermented Shrimp Paste.

This study was conducted to investigate the effect of inoculation with Exiguobacterium profundum FELA1 isolated from traditional shrimp paste and koji on the taste, flavor characteristics, and bacterial community of rapidly fermented shrimp paste. E-nose and e-tongue results showed higher levels of alcohols, aldehydes, and ketones, enhanced umami and richness, and reduced bitterness and astringency in samples of shrimp paste inoculated with fermentation (p < 0.05). Eighty-two volatile compounds were determined using headspace solid-phase microextraction and gas chromatography-mass spectrometry (HS-SPEM-GC-MS). The contents of 3-methyl-1-butanol, phenylethanol, isovaleraldehyde, and 2-nonanone in the inoculated samples were significantly increased (p < 0.05), resulting in pleasant odors such as almond, floral, and fruity. High-throughput sequencing results showed that the addition of koji and FELA1 changed the composition and abundance of bacteria and reduced the abundance of harmful bacteria. Spearman's correlation coefficient indicated that the alcohols, aldehydes, and ketones of the inoculated fermented samples showed a strong correlation (|ρ| > 0.6) with Virgibacillus and Exiguobacterium, which contributed to the formation of good flavor in the fast fermented shrimp paste. This study may offer new insights into the production of rapidly fermented shrimp paste with better taste and flavor.

Olfactory perceptual fingerprints of people with olfactory dysfunction and healthy controls.

An olfactory perceptual fingerprint (OPF) defines one's olfactory perception using perceptual descriptor ratings (such as odor pleasantness, intensity) for a set of odors. OPFs have been shown to distinguish patients with COVID-related olfactory dysfunction (OD) and healthy controls with 86% accuracy. However, all participants rated the same odorants. With the aim to evaluate whether the OPFs are indeed odorant independent, previously published dataset by Lötsch et al. was reanalyzed. Furthermore, this independent dataset was used to check whether the OPFs separate patients with OD due to various causes from controls. The study included 104 controls and 42 patients, who were randomized into four odor sets with 10 odorants each. Odorants were presented using a computer-controlled olfactometer and evaluated on scales from 1 (not at all) to 5 (very) using perceptual descriptors pleasant, intensive, familiar, edible, irritating, cold/warm, and painful. Permutational multivariate analysis of variance showed that the odor set did not have a significant effect on the OPFs, confirming that the OPFs are indeed odorant independent. On the other hand, both diagnosis and age affected the OPFs (p < .001) and explained around 11% and 5% of the variance of the OPFs, respectively. Furthermore, a supervised machine learning method, random forest classifier, showed that OPF can distinguish patients and controls with 80% accuracy. OPFs are odorant independent. Patients perceived odors as less familiar, less intense, and less edible than controls. Other perceptual descriptors were much less important for the separation of patients and controls. 3.

D-Limonene reduces depression-like behaviour and enhances learning and memory through an anti-neuroinflammatory mechanism in male rats subjected to chronic restraint stress.

D-limonene is a widely used flavouring additive in foods, beverages and fragrances due to its pleasant lemon-like odour. This study aimed to investigate the effects of D-limonene on the central nervous system when subjected to chronic restraint stress in rats for 21 days. Forty rats were randomly divided into five groups: i) control, ii) D-limonene, iii) restraint stress, iv) restraint stress+D-limonene and v) restraint stress+fluoxetine. Following the induction of restraint stress, the sucrose preference test, the open field test, the novel object recognition test and the forced swimming test were performed. The levels of BDNF, IL-1β, IL-6 and caspase-1 were measured from hippocampal tissue using the ELISA method. Sucrose preference test results showed an increase in consumption rate in the stress+D-limonene and a decrease in the stress group. The stress+D-limonene group reversed the increased defensive behaviour observed in the open-field test compared to the stress group. In the novel object recognition test, the discrimination index of the stress+D-limonene group increased compared to the stress group. BDNF levels increased in the stress+limonene group compared to the stress group. In contrast, IL-1β and caspase-1 levels increased in the stress group compared to the control and decreased in the stress+limonene group compared to the stress group. In this study, D-limonene has been found to have antidepressant-like properties, reducing anhedonic and defensive behaviours and the impairing effects of stress on learning and memory tests. It was observed that D-limonene showed these effects by alleviating neuroinflammation induced by chronic restraint stress in rats.

Biochemical Analysis of Melia azedarach (Chinaberry) Leaf Extract Collected from Laoang, Northern Samar, Philippines

Melia azedarach belongs to the Meliaceae family and is known by various names, such as Chinaberry, ride of India, Bead-tree, Cape lilac, Persian lilac. It is commonly found in warmer and tropical regions, including Southeast Asia and various other parts of the world. The leaves, bark, stem and roots have a medicinal application and effective against the herpes simplex virus. This study focuses on the characterization of bioactive potential of Melia azedarach (Chinaberry) leaf extract. Physical properties were determined in terms of color, odor, solubility, boiling point, density, and pH. Furthermore, the secondary metabolites were determined in terms of alkaloids, phenols, tannin, saponin, and phenolic compound. Likewise, Fourier-Transform Infrared Spectroscopy is used to determine the functional group present on the leaf extract. Lastly, to determine the bioactive potential of Melia azedarach (Chinaberry) leaf extract Ultraviolet Visible (UV-vis) Spectrophotometer was used. Result showed that Melia azedarach (Chinaberry) has a yellow green color with a pleasant odor, miscible with ethanol and water, immiscible with benzene, lower boiling point than water, less dense than water and a pH which is moderately acidic. Furthermore, a positive result showed in phytochemical screening for alkaloids, phenols, tannin, saponin and phenolic compound, which implies that the plant sample can be used as antioxidant, analgesic, and anti-inflammatory. Subsequently, FTIR and UV-vis analysis showed a positive result for the determination of functional group and bioactive potential among secondary metabolites which means that it is possible for the application in developing therapeutic medicines and in developing natural remedies. Therefore, the findings of this study will benefits the whole scientific community since it would provide added information and evidences as possible application for the development of pharmaceutical medicine. Furthermore, this study is beneficial to the whole scientific community since it would provide added information about the characterization of bioactive potential present in these leaf extract. It also, provides alternative treatments for common health issues particularly in communities that are in far-flung areas with limited access to modern healthcare. Overall, this compound simplifies treatments, may lower healthcare costs, and significantly improves quality of life.

Development and nutritional assessment of Ojas cookies using Ojaswini Churna and millet's flour

Abstract BACKGROUND: The therapeutic efficacy of Ayurveda for chronic ailments and limitations of mainstream medicine has spurred an exploration of alternative interventions. This study is aimed to develop Ojas cookies by using Ojaswini Churna (Ayurvedic proprietary medicine) and millets flour along with its nutritional assessment. METHODS: Authentic botanicals, comprising Ayurvedic herbs and organic millet flours, were procured. Later, Ojaswini Churna was prepared following the Formulary of National Institute of Ayurveda (Deemed to be University) Jaipur. Subsequently, Ojas cookies were developed via three pilot methods using millet flour, followed by analytical assessment of organoleptic, physicochemical, nutritional, and microbiological parameters. RESULTS: The final formulation derived from pilot method 3 exhibited optimal palatability, adequate crispness, odor, and uniformity. Each Ojas cookie weighed 15 g and exhibited uniform circular shape with pleasant odor. Analytical profiling revealed the presence of macronutrients such as carbohydrates, proteins, lipids, dietary fiber, vitamins, calcium, and iron. Microbiological examination showed the absence of Escherichia coli, Salmonella, yeast and mold, and coliform bacteria. CONCLUSION: This study aims to integrate Ayurvedic principles with contemporary nutritional insights. The conversion of Ojaswini Churna into macronutrient-enriched cookies aligns with the bakery industry’s growth and nutritional significance of millets, especially in the context of the International Year of Millets 2023. The conversion of Ojaswini Churna into Ojas cookies represents the convergence of traditional and contemporary approaches. Ojas cookies offer a promising avenue for addressing health concerns, highlighting the nutritional potential of millets.

Optimization of thermosonication conditions for critical quality parameters of watermelon juice using response surface methodology

Topical consumer interest in natural, healthier, safer and nutritional juice, has inspired the search for innovative technologies that can minimize product degradation. In this regard, thermosonication has been proposed as a potential processing technology that can preserve and produce “fresh” products. Watermelon (Citrulluslanatus) juice is a nutrient-rich fruit juice that is desired by consumers due to its appealing color, pleasant odor, sweet taste and low-calorie content. This fruit juice is, however, highly perishable and prone to microorganisms, because of its neutral pH value and high amount of water activity. In addition, it is thermo-sensitive and therefore degrades quickly under thermal processing. This study aimed to identify the optimal thermosonication processing conditions for retaining the critical quality parameters (lycopene, β-carotene, ascorbic acid and total polyphenolic content) of watermelon juice. Response surface methodology, employing a central composite design, was used to determine the effects of temperature (18–52 °C), processing time (2–13 min) and amplitude level (24–73 μm) at a constant frequency of 25 kHz. The highest quality parameters were obtained at 25 °C, 2 min, and 24 µm at a constant frequency of 25 kHz, which resulted in lycopene of 8.10 mg/100 g, β-carotene of 0.19 mg/100 g, ascorbic acid of 3.11 mg/100 g and total polyphenolic content of 23.96 mg/GAE/g with a desirability of 0.81. The proposed model was adequate (p < 0.0001), with a satisfactory determination coefficient (R2) of less than 0.8 for all phytochemicals. Thermosonicated watermelon juice samples showed minimal changes in their phytochemical properties, when compared to fresh juices; the lycopene content showed a significant increase after thermosonication, and a significant retention of β-carotene, ascorbic acid and total polyphenolic acid was observed. According to the findings, thermosonication could be a viable method for preserving watermelon juice, with minimal quality loss and improved functional attributes.

Using Exceptional Attributed Subgraph Mining to Explore Interindividual Variability in Odor Pleasantness Processing in the Piriform Cortex &amp; Amygdala

Using Exceptional Attributed Subgraph Mining to Explore Interindividual Variability in Odor Pleasantness Processing in the Piriform Cortex &amp; Amygdala

Insight into the antibacterial properties of terpinen-4-ol on planktonic growth and biofilm-formation of Vibrio parahaemolyticus

Vibrio parahaemolyticus outbreaks emphasize the urgency of highly efficient prevention strategies to control this foodborne pathogen. This study investigated the antibacterial effects of terpinen-4-ol on V. parahaemolyticus RIMD2210633 and explored the underlying mechanism via RNA-seq analysis. The results showed that terpinen-4-ol inhibited V. parahaemolyticus efficiently with minimum inhibitory concentration and minimum bactericidal concentration values at 0.8 μL/mL. Scanning electron microscopy and PI/SYTO 9 staining assay demonstrated that cell morphology and cell membrane integrity were dose-dependently destructed. Additionally, biofilm formation was significantly inhibited according to crystal violet and MTT assay analysis. Notably, terpinen-4-ol showed good inhibitory activity against V. parahaemolyticus on salmon fillets via fumigation at 4 °C. Transcriptional analysis revealed significant downregulation of genes participated in cell wall formation (oppB, oppF), cell membrane integrity, pilus assembly protein, biofilm formation and cell motility (ToxR , LuxR), capsular polysaccharide biosynthesis protein, type IV pilin MshA and mannose-sensitive haemagglutinin type-IV pili (MSHA) biogenesis protein (MshJ, MshJ, MshK, MshL, MshN). The results demonstrated that terpinen-4-ol can efficiently inhibit the growth and pathogenicity of V. parahaemolyticus. With its safety and pleasant odor, terpinen-4-ol can be developed as a natural antibacterial substance to tackle V. parahaemolyticus contamination in food preservation and prevent associated diseases.

Is the perception of odour pleasantness shared across cultures and ecological conditions? Evidence from Amazonia, East Africa, New Guinea, Malaysia and Poland.

What makes an odour pleasant or unpleasant? The inherent properties of the constituent chemical compounds, or the nose of the beholder, driven by idiosyncratic differences and culture-specific learning? Here, 582 individuals, including Tanzanian Hadza hunter-gatherers, Amazonian Tsimane' horticulturalists, Yali from the Papuan highlands and two industrialized populations (Poles, Malaysians), rated the pleasantness of 15 odour samples. We find considerable similarities in odour assessments across cultures, but our data do not fully support a claim regarding the universality of smell preferences. Despite cross-cultural similarities in olfactory assessments, probably driven by odour properties, we suggest that odour availability in ecological and cultural niches bears an undeniable effect on human odour preferences.