Analytical characterization of volatiles present in the whole body odour of zebra finches.

In recent decades, the compositions of preen oil and feathers have been studied to achieve insights into the chemistry of avian odours, which play a significant role in birds' social behaviour. Fewer studies are available regarding volatiles originating from other sources, such as faeces, eggs or a bird's whole body. The aims of this study were (i) to identify odour-active and further volatile compounds in zebra finch whole body odour and (ii) to semi-quantify selected volatiles and use the information to evaluate two different adsorbents for their suitability for whole body odour sampling.

Identification of odor-active compounds in Nile tilapia (Oreochromis niloticus) from recirculated aquaculture systems: A case study with different depuration procedures.

Off-flavors are a major challenge for companies using recirculated aquaculture systems (RAS). In the presented work, we comprehensively characterize the odorant composition of Nile tilapia (Oreochromis niloticus) raised in RAS and compare the impact of two depuration processes on the odorant composition and aroma profile of the fish. Fish collected from the production tank and after two different tank pre-disinfection approaches in the depuration process (high pH versus HO) were investigated.

Characterization of a Human Respiratory Mucosa Model to Study Odorant Metabolism.

Nasal xenobiotic metabolizing enzymes (XMEs) are important for the sense of smell because they influence odorant availability and quality. Since the major part of the human nasal cavity is lined by a respiratory mucosa, we hypothesized that this tissue contributed to nasal odorant metabolism through XME activity. Thus, we built human respiratory tissue models and characterized the XME profiles using single-cell RNA sequencing.

Curry-Odorants and Their Metabolites Transfer into Human Milk and Urine.

Scope: The excretion of dietary odorants into urine and milk is evaluated and the impact of possible influencing factors determined. Furthermore, the metabolic relevance of conjugates for the excretion into milk is investigated.

Methods And Results: Lactating mothers (n = 20) are given a standardized curry dish and donated one milk and urine sample each before and 1, 2, 3, 4.

Body odor samples from infants and post-pubertal children differ in their volatile profiles.

Body odors change during development, and this change influences the interpersonal communication between parents and their children. The molecular basis for this chemical communication has not been elucidated yet. Here, we show by combining instrumental and sensory analyses that the qualitative odorant composition of body odor samples is similar in infants (0-3 years) and post-pubertal children (14-18 years).

Volatile organic compounds in preen oil and feathers - a review.

For a long time birds were assumed to be anosmic or at best microsmatic, with olfaction a poorly understood and seldom investigated part of avian physiology. The full viability of avian olfaction was first discovered through its functions in navigation and foraging. Subsequently, researchers have investigated the role of olfaction in different social and non-social contexts, including reproduction, kin recognition, predator avoidance, navigation and foraging.

Linalool, 1,8-Cineole, and Eugenol Transfer from a Curry Dish into Human Urine.

Scope: For most substances, there are several routes of excretion from the human body. This study focuses on urinary excretion of dietary odorants and compares the results with previously obtained results on excretion into milk.

Methods And Results: Lactating mothers (n = 18) are given a standardized curry dish and donate urine samples before and after the intervention.

Unraveling the universality of chemical fear communication: evidence from behavioral, genetic, and chemical analyses.

Abundant evidence indicates that humans can communicate threat-related information to conspecifics through their body odors. However, prior research has been primarily conducted on Western (WEIRD) samples. In this study, we aimed to investigate whether threat-related information can be transmitted by individuals of East Asian descent who carry a single-nucleotide polymorphism (SNP) 538G → A in the ABCC11 gene, which significantly reduces (noticeable) body odor.

Perspectives on Nasal Odorant Metabolism Research.

Olfaction is a multi-step process. At a peripheral level, nasal odorant metabolism contributes to olfaction via signal termination, variation, and regulation. We summarize current techniques used to investigate nasal odorant metabolism and give an outlook on future approaches, such as nasal tissue models and their potential contributions in future research directions.

Past, Present, and Future of Human Chemical Communication Research.

Although chemical signaling is an essential mode of communication in most vertebrates, it has long been viewed as having negligible effects in humans. However, a growing body of evidence shows that the sense of smell affects human behavior in social contexts ranging from affiliation and parenting to disease avoidance and social threat. This article aims to (a) introduce research on human chemical communication in the historical context of the behavioral sciences; (b) provide a balanced overview of recent advances that describe individual differences in the emission of semiochemicals and the neural mechanisms underpinning their perception, that together demonstrate communicative function; and (c) propose directions for future research toward unraveling the molecular principles involved and understanding the variability in the generation, transmission, and reception of chemical signals in increasingly ecologically valid conditions.

Can you smell my stress? Influence of stress chemosignals on empathy and emotion recognition in depressed individuals and healthy controls.

Human body odors contain chemical signals that play a key role in our non-verbal communication regarding health, genetic identity, immune system, fitness, and emotional state. Studies on human chemosignaling in individuals with psychiatric diseases are scarce but indicate altered smell perception and emotion recognition in depressed individuals. In the present project, we aimed to investigate the influence of chemosensory substances in social stress sweat on emotion recognition, perspective taking, affective responsiveness as well as stress level in healthy and depressed individuals.

Recovery rates of selected body odor substances in different textiles applying various work-up and storage conditions measured by gas chromatography-mass spectrometry.

Background: Body odor is an important aspect in interpersonal communication. For psychological and chemical research on body odors, suitable procedures for sampling and application, and analysis of body odors are essential. In this study, different textile fabrics (polyester, cotton, and Gazin gauze) were comparatively evaluated in view of their potential suitability for body odor sampling by determining recovery rates of selected body odor substances.

Smells like new car or rather like an old carriage? - Resolution of the decay behavior of odorants in vehicle cabins during usage.

The typical new car smell is not only perceived directly after vehicle delivery. Vehicle interiors maintain their characteristic odors for a period of time during use even though the gas composition of the vehicle interior changes due to external influences. To obtain deeper insights into the odorant composition of a passenger cabin, this study aimed at characterizing the gas phase of two vehicle interiors at defined time intervals after vehicle delivery, and use by a customer in a controlled environment using a targeted odorant analysis.

Odorant Metabolism in Humans.

Odorants are relatively small molecules which are easily taken up and distributed in the human body. Despite their relevance in everyday life, however, only a limited amount of evidence about their metabolism, pathways, and bioactivities in the human body exists. With this Review, we aim to encourage future interdisciplinary research on the function and mechanisms of the biotransformation of odorants, involving different disciplines such as nutrition, medicine, biochemistry, chemistry, and sensory sciences.

Follow your nose - Traveling the world of odorants in new cars.

Volatile organic compounds of the vehicle interior are well investigated, but only limited information is available on the odorants of the passenger cabin. To close this gap, we aimed at specifically elucidating the odor, as a general proof of principle, of two new cars with different seat upholstery in a controlled environment using a targeted odorant analysis. In a first step, odor profiles were evaluated by a descriptive sensory analysis.

Dietary Linalool is Transferred into the Milk of Nursing Mothers.

Scope: Breast milk is repeatedly postulated to shape the first aroma and taste impressions of infants and thus impact their flavor learning. The objective of this study is to assess the transition of aroma compounds from a customary curry dish into milk.

Methods And Results: The article prepares a standardized curry dish and administers the dish to nursing mothers (n = 18) in an intervention study.

Dietary Piperine is Transferred into the Milk of Nursing Mothers.

Introduction: The diet of breastfeeding mothers could bring nurslings into contact with flavor compounds putatively contributing to early sensory programming of the infant. The study investigates whether tastants from a customary curry dish consumed by mothers are detectable in their milk afterwards and can be perceived by the infant.

Methods And Results: Sensory evaluation identifies pungency as the dominating taste impression of the curry dish.

Sesquiterpenes and sesquiterpenoids harbor modulatory allosteric potential and affect inhibitory GABA receptor function in vitro.

Naturally occurring compounds such as sesquiterpenes and sesquiterpenoids (SQTs) have been shown to modulate GABA receptors (GABA Rs). In this study, the modulatory potential of 11 SQTs at GABA Rs was analyzed to characterize their potential neurotropic activity. Transfected HEK293 cells and primary hippocampal neurons were functionally investigated using electrophysiological whole-cell recordings.

Isolation of sesquiterpenoids from Matricaria chamomilla by means of solvent assisted flavor evaporation and centrifugal partition chromatography.

The (semi)volatile fraction of Matricaria chamomilla L., an annual herbal plant from the family of Asteraceae, contains high quantities of sesquiterpenes and sesquiterpenoids. A method was developed to achieve isolation and separation of these compounds, using a combination of solvent assisted flavor evaporation (SAFE) and solid support-free liquid-liquid chromatography.

A systematic review of physiological responses to odours with a focus on current methods used in event-related study designs.

Objectives: In odour research, there is still a lack of knowledge regarding the detailed understanding of the determinants and the magnitude of an odour's impact on human psychophysiology. Therefore, the present review aims to summarize current evidence on psychophysiological responses to olfactory events, to highlight diversity in research methods, and to provide recommendations for further research.

Material And Methods: Predefined search items were used for literature research in two databases, focussing on recent investigations of cardiac and electrodermal responses to short (<10 s) olfactory stimulations, combined with self-reports on odour experience, in a healthy population.

Quantification of Allyl Methyl Sulfide, Allyl Methyl Sulfoxide, and Allyl Methyl Sulfone in Human Milk and Urine After Ingestion of Cooked and Roasted Garlic.

Due to its characteristic flavor and positive effects on human health, garlic is a highly valued food ingredient. Consumption of garlic alters the quality of body odors, which may in some instances hinder social interaction but be beneficial in other contexts, as it is assumed to contribute to early flavor learning in the breastfeeding context, for example. In previous work, allyl methyl sulfide (AMS) has been identified as the major odor-active metabolite in urine and milk, being excreted together with the odorless metabolites allyl methyl sulfoxide (AMSO) and allyl methyl sulfone (AMSO) after ingestion of raw garlic.

Olfaction scaffolds the developing human from neonate to adolescent and beyond.

The impact of the olfactory sense is regularly apparent across development. The fetus is bathed in amniotic fluid (AF) that conveys the mother's chemical ecology. Transnatal olfactory continuity between the odours of AF and milk assists in the transition to nursing.

Diet-Induced Flavor Changes in Human Milk: Update and Perspectives.

Dietary aroma transfer into human milk has been studied in many scenarios, including direct transmission and biotransformation. This perspective highlights recent research that focuses on the latter, with examples given in relation to 1,8-cineole and garlic-derived odorants. Three future directions are discussed, comprising (a) achieving a more comprehensive understanding of the chemical and physiological basis of aroma transfer into milk via pharmacological methods, advanced analytical techniques, and ecologically valid study designs, (b) assessing the bioactivity of odorants and their metabolites present in milk that are ingested by the infant, and (c) translating the insights gained on aroma transmission in relation to taste attributes and bioactive components of the maternal diet.

A Masked Aversive Odor Cannot Be Discriminated From the Masking Odor but Can Be Identified Through Odor Quality Ratings and Neural Activation Patterns.

Odor masking is a very prominent problem in our daily routines, mainly concerning unpleasant sweat or toilet odors. In the current study we explored the effectiveness of odor masking both on a behavioral and neuronal level. By definition, participants cannot differentiate a fully masked unpleasant odor from the pleasant pure odor used as a masking agent on a behavioral level.

The odour of human milk: Its chemical variability and detection by newborns.

Human milk odour has for long elicited research interest with regard to its function in breastfeeding initiation. The present review aims to provide an overview of the behavioural effects of human milk odour in the human neonate, considering different types of response measures in a feeding or non-feeding context. Further, an overview of the current knowledge of odorant composition and factors influencing milk odour is provided by summarizing results from analytical studies using olfactometry, and addressing changes in milk odour due to storage, lactational stage, and maternal dietary intake of odorous substances.