Chemical composition from photos: Dried solution drops reveal a morphogenetic tree.

Under nonequilibrium conditions, inorganic systems can produce a wealth of life-like shapes and patterns which, compared to well-formed crystalline materials, remain widely unexplored. A seemingly simple example is the formation of salt deposits during the evaporation of sessile droplets. These evaporites show great variations in their specific patterns including single rings, creep, small crystals, fractals, and featureless disks. We have explored the patterns of 42 different salts at otherwise constant conditions. Based on 7,500 images, we show that distinct pattern families can be identified and that some salts (e.g., Na2SO4 and NH4NO3) are bifurcated creating two distinct motifs. Family affiliations cannot be predicted a priori from composition alone but rather emerge from the complex interplay of evaporation, crystallization, thermodynamics, capillarity, and fluid flow. Nonetheless, chemical composition can be predicted from the deposit pattern with surprisingly high accuracy even if the set of reference images is small. These findings suggest possible applications including smartphone-based analyses and lightweight tools for space missions.

Rebound or Cage Escape? The Role of the Rebound Barrier for the Reactivity of Non-Heme High-Valent FeIV =O Species.

Owing to their high reactivity and selectivity, variations in the spin ground state and a range of possible pathways, high-valent FeIV =O species are popular models with potential bioinspired applications. An interesting example of a structure-reactivity pattern is the detailed study with five nonheme amine-pyridine pentadentate ligand FeIV =O species, including N4py: [(L1 )FeIV =O]2+ (1), bntpen: [(L2 )FeIV =O]2+ (2), py2 tacn: [(L3 )FeIV =O]2+ (3), and two isomeric bispidine derivatives: [(L4 )FeIV =O]2+ (4) and [(L5 )FeIV =O]2+ (5). In this set, the order of increasing reactivity in the hydroxylation of cyclohexane differs from that with cyclohexadiene as substrate. A comprehensive DFT, ab initio CASSCF/NEVPT2 and DLPNO-CCSD(T) study is presented to untangle the observed patterns. These are well reproduced when both activation barriers for the C-H abstraction and the OH rebound are taken into account. An MO, NBO and deformation energy analysis reveals the importance of π(pyr) → π*xz (FeIII -OH) electron donation for weakening the FeIII -OH bond and thus reducing the rebound barrier. This requires that pyridine rings are oriented perpendicularly to the FeIII -OH bond and this is a subtle but crucial point in ligand design for non-heme iron alkane hydroxylation.

Prolonged Dark Chemical Processes in Secondary Organic Aerosols on Filters and in Aqueous Solution.

Secondary organic aerosol (SOA) represents a large fraction of atmospheric aerosol particles that significantly affect both the Earth's climate and human health. Laboratory-generated SOA or ambient particles are routinely collected on filters for a detailed chemical analysis. Such filter sampling is prone to artifactual changes in composition during collection, storage, sample workup, and analysis. In this study, we investigate the chemical composition differences in SOA generated in the laboratory, kept at room temperature as aqueous extracts or on filters, and analyzed in detail after a storage time of a day and up to 4 weeks using liquid chromatography coupled to high-resolution mass spectrometry. We observe significantly different temporal concentration changes for monomers and oligomers in both extracts and on filters. In SOA aqueous extracts, many monomers increase in concentration over time, while many dimers decay at the same time. In contrast, on filters, we observe a strong and persistent concentration increase of many dimers and a decrease of many monomers. This study highlights artifacts arising from SOA chemistry occurring during storage, which should be considered when detailed organic aerosol compositions are studied. The particle-phase reactions on filters can also serve as a model system for atmospheric particle aging processes.

Plastic Food Packaging from Five Countries Contains Endocrine- and Metabolism-Disrupting Chemicals.

Plastics are complex chemical mixtures of polymers and various intentionally and nonintentionally added substances. Despite the well-established links between certain plastic chemicals (bisphenols and phthalates) and adverse health effects, the composition and toxicity of real-world mixtures of plastic chemicals are not well understood. To assess both, we analyzed the chemicals from 36 plastic food contact articles from five countries using nontarget high-resolution mass spectrometry and reporter-gene assays for four nuclear receptors that represent key components of the endocrine and metabolic system. We found that chemicals activating the pregnane X receptor (PXR), peroxisome proliferator receptor γ (PPARγ), estrogen receptor α (ERα), and inhibiting the androgen receptor (AR) are prevalent in plastic packaging. We detected up to 9936 chemical features in a single product and found that each product had a rather unique chemical fingerprint. To tackle this chemical complexity, we used stepwise partial least-squares regressions and prioritized and tentatively identified the chemical features associated with receptor activity. Our findings demonstrate that most plastic food packaging contains endocrine- and metabolism-disrupting chemicals. Since samples with fewer chemical features induce less toxicity, chemical simplification is key to producing safer plastic packaging.

Analytical strategies to identify multicomponent quality markers for commercial Hua-ju-hong using multidimensional chemical analysis.

Hua-ju-hong (HJH) is a Chinese medicinal material obtained from Citrus grandis 'Tomentosa' (CGT) and Citrus grandis (L.) Osbeck (CG) with various commercial specifications. It is known for relieving cough and dispelling phlegm. To reveal the quality marker for distinguishing the various HJH, 215 batches of commercial HJH were studied systematically using multidimensional chemical analysis. Ten major components were identified by high-performance liquid chromatography coupled with quadrupole-time-of-flight mass spectrometry and quantified via high-performance liquid chromatography coupled with diode array detection. In this study, a rapid, efficient, and low-cost chromatographic method was established. Total coumarin-hemiterpene and total coumarin-monoterpene were first classified and analyzed in HJH. The result indicated that the main component, naringin, was not the quality marker for differentiating CGT from CG. For reflecting the unique medicinal and food value of HJH, coumarins should be the more potential quality markers. Flavonoids were the possible quality markers for distinguishing two growth stages of fruit-exocarp and young fruit. For the first time, two chemotypes of HJH were identified in CG. This study provides a convenient yet reliant chromatographic method and novel yet systematic strategies for overall quality control of commercial HJH.

Rearing and 60Co radiation do not affect attractiveness but alter the volatile profiles released by Anastrepha obliqua calling males.

Calling males of Anastrepha obliqua release volatile compounds to attract conspecific males to form leks and females to mate. Male volatiles from Mexican and Brazilian populations of A. obliqua have been previously identified. However, there are differences in the number and identity of volatile compounds between the populations. These differences in volatile profiles may be due to male origin (e.g. wild or mass-reared flies) or methodological issues (e.g. sampling techniques). In this study, we evaluated the attractiveness of wild, laboratory non-irradiated, and laboratory-irradiated flies under semi-field conditions. Male volatiles were collected using dynamic headspace sampling (DHS) and solid-phase microextraction (SPME) techniques, and identified using gas chromatography-coupled mass spectrometry. The results showed no difference in the attractiveness of wild, laboratory non-irradiated, and irradiated males to females. However, the number of captured females differed according to the origin; wild and non-irradiated females were captured more frequently than the irradiated flies. A total of 21 compounds were found using SPME, whereas only 12 were collected using DHS, although the relative amounts of these compounds were higher than those obtained using the former sampling technique. In addition, only laboratory non-irradiated males released α-pinene and menthol, which have not been previously reported in this fruit fly species. Additionally, we identified novel compounds in A. obliqua; however, certain compounds previously reported were not detected. This study suggests that despite the qualitative and quantitative variations in the volatile profiles of A. obliqua males, their attractiveness was unaffected.

Oral lichenoid lesions in two snuff users with contact allergy to carvone.

BACKGROUND: Contact allergy to the mint-tasting flavour carvone has been observed in patients with oral lichenoid lesions (OLL). Mint-flavoured products such as toothpaste frequently contain carvone. Snuff is a smokeless tobacco product that is chewed or placed in the mouth rather than smoked. In Sweden, the use of snuff and its flavoured versions is extremely common. OBJECTIVES: To investigate whether the consumption of mint-flavoured snuff is associated with contact allergy to carvone and subsequently plays a role in the aetiology of OLL. METHODS: Regarding the two patients, patch testing with snuff pouches was performed. High-performance liquid chromatography and gas chromatography-mass spectrometry analysis were used for identification of carvone in different snuff samples. RESULTS: Two patients with OLL were contacted allergic to carvone when patch tested. Both were using mint-flavoured snuffs several hours a day for many years. One patient was contacted allergic to the snuff pouch tested as is. Carvone was detected in the snuff samples of both patients. CONCLUSIONS: The patients were recommended to avoid the use of mint-flavoured snuffs, toothpaste and foodstuffs. At follow-up 3 months later, the patients had a dramatic clinical improvement of the OLL and oral symptoms. Exposure to mint-flavoured snuffs can be overlooked as a possible aggravating/provoking factor in OLL.

2-Cyanoethyl dimethyldithiocarbamate, a new contact allergen found in accelerator-free nitrile gloves.

BACKGROUND: Allergic contact dermatitis (ACD) from rubber glove usage is usually caused by rubber additives such as the accelerators. However, in analyses of the suspected gloves, ordinary rubber allergens are not always found. Accelerator-free rubber gloves are available, but some patients with accelerator allergy do not tolerate them and might also be patch test positive to them. OBJECTIVES: To identify and chemically characterize a new allergen, 2-cyanoethyl dimethyldithiocarbamate (CEDMC), in rubber gloves. We describe two patient cases: patient 1 that led us to the identification of CEDMC and patient 2 with occupational ACD caused by CEDMC. METHODS: The patients were examined with patch testing including baseline and rubber series, and their own rubber gloves. High-performance liquid chromatography (HPLC) was used for chemical analysis of rubber gloves. The allergen was synthesized and identified by nuclear magnetic resonance, mass spectrometry and infrared spectrometry, and tested on patient 2. RESULTS: CEDMC was identified by HPLC in a nitrile glove associated with hand eczema in patient 1. Patient 2 whose nitrile gloves contained CEDMC was patch test positive to CEDMC. CONCLUSIONS: CEDMC is a new contact allergen in nitrile gloves and probably forms during vulcanization from residual monomer acrylonitrile and rubber additives.

Design Aspects for Portable LED-Based Colorimetric Characterisation Systems Targeting Liquid Analytes.

Colorimetric characterisation systems based on LEDs and RBG sensors are straightforward to implement, are highly integrable allowing for portable measurement systems and can be constructed using widespread and affordable components. They have already proved to be a satisfactory solution in several applications related to chemical analysis. In this paper, we present an RGB sensor-based prototype for colorimetric characterisation, which can accommodate cuvettes with optical paths of 10 mm and 40 mm. We assessed the impact of experimental condition parameters such as the variability of the analyte volume in the cuvette, as well as the presence of floating particles or deposits at the bottom of the cuvette. While these would not impact the result given by a spectrophotometer that generally has a directional light source, they must be considered in LED/RGB sensor analysers in which the light path is not tightly controlled. We demonstrated that there is a minimal sensor height above the bottom of the cuvette and a minimal analyte level (both depending on the prototype optical path length) above which the analyte volume and the presence of floating particles and deposits have no impact on the prototype output signal. Finally, based on these results, we proposed a test method for a quick dye-displacement assay, in which the reagent is a dye-loaded molecularly imprinted polymer that is poured directly into a cuvette.

LVI and DI-SPME Combined with GC/MS and GC/MS for Volatile Chemical Profile Investigation and Cytotoxic Power Evaluation of Essential Oil and Hydrolate from Cannabis sativa L. cv. Carmagnola.

Cannabis sativa L. is a plant that has been cultivated since ancient times thanks to its various uses. Even its extraction products, such as essential oil and hydrolate, having a varied chemical composition and rich in bioactive components, find wide use in different sectors, gathering ever-increasing interest over time. In this work, the essential oil of Cannabis sativa L. cv. Carmagnola was characterized by using Gas Chromatography/Mass Spectrometry (GC/MS) and, for the first time, the chemical profile of the hydrolate was also described through different analytical techniques such as Large-Volume Injection Gas Chromatography/Mass Spectrometry (LVI-GC/MS) and Direct Immersion-Solid Phase Microextraction-Gas Chromatography/Mass spectrometry (DI-SPME-GC/MS), in order to provide a more complete compositional profile. The results of the analyses conducted on the hydrolate highlighted a high content of α-terpineol; on the other side, in the essential oil, a prevalence of monoterpenes, with α-pinene and limonene as the characterizing components, was detected. Both matrices were also investigated to evaluate their cytotoxic activity by using a panel of cancer cell lines derived from different histotypes such as melanoma (A375, LOX IMVI), non-small cell lung cancer (H1299, A549), colon (HT29) and pancreatic (L3.6) cancer cell lines. The obtained data demonstrated that essential oil was more effective than hydrolate in terms of reduction in cell viability.

Integrating Transcriptome and Chemical Analyses to Provide Insights into Biosynthesis of Terpenoids and Flavonoids in the Medicinal Industrial Crop Andrographis paniculate and Its Antiviral Medicinal Parts.

Andrographis paniculata is a medicinal plant traditionally used to produce diterpene lactones and flavonoids, which possess various biological activities. Widely distributed in China, India, and other Southeast Asia countries, A. paniculata has become an important economic crop, significantly treating SARS-CoV-2, and is being cultivated on a large scale in southern China. The biosynthesis of active ingredients in A. paniculata are regulated and controlled by genes, but their specific roles are still not fully understood. To further explore the growth regulation factors and utilization of its medicinal parts of this industrial crop, chemical and transcriptome analyses were conducted on the roots, stems, and leaves of A. paniculata to identify the biosynthesis pathways and related candidate genes of the active ingredients. The chemical analysis revealed that the main components of A. paniculata were diterpene lactones and flavonoids, which displayed potential ability to treat SARS-CoV-2 through molecular docking. Moreover, the transcriptome sequencing annotated a total of 40,850 unigenes, including 7962 differentially expressed genes. Among these, 120 genes were involved in diterpene lactone biosynthesis and 60 genes were involved in flavonoid biosynthesis. The expression of diterpene lactone-related genes was the highest in leaves and the lowest in roots, consistent with our content determination results. It is speculated that these highly expressed genes in leaves may be involved in the biosynthesis pathway of diterpenes. Furthermore, two class Ⅰ terpene synthases in A. paniculata transcriptome were also annotated, providing reference for the downstream pathway of the diterpene lactone biosynthesis. With their excellent market value, our experiments will promote the study of the biosynthetic genes for active ingredients in A. paniculata and provide insights for subsequent in vitro biosynthesis.

In vitro diffusion of plant phenolics through the skin: A review update.

OBJECTIVE: Excessive skin exposure to deleterious environmental variables results in inflammation as well as molecular and cellular impairments that compromise its functionality, aesthetic qualities, and overall well-being. The implementation of topical administration of antioxidants and other compounds as a method for preventing or reversing damage is a rational approach. Numerous phenolic compounds derived from plants have demonstrated capabilities such as scavenging free radicals and promoting tissue healing. However, the primary obstacle lies in effectively delivering these compounds to the specific place on the skin, and accurately forecasting their diffusion through the skin can assist in determining the most effective tactics. Hence, this article provides a comprehensive analysis of recent literature pertaining to the in vitro skin diffusion characteristics of plant phenolics. The aim is to gain a deeper understanding of their behaviour when present in various forms such as solutions, suspensions, and formulations. METHOD: The data on plant extracts and isolated plant phenolic compounds in vitro skin diffusion assays published over the last six years were compiled and discussed. RESULTS: Even though the gold standard Franz diffusion cell is the most commonly used in the assessment of in vitro plant phenolic skin diffusion profiles, a plethora of skin models and assay conditions are reported for a variety of compounds and extracts in different vehicles. CONCLUSION: The presence of numerous models and vehicles poses a challenge in creating correlations among the existing data on plant phenolic compounds. However, it is possible to draw some general conclusions regarding molecular, vehicle, and skin characteristics based on the gathered information.

OBJECTIF: Une exposition excessive de la peau a des variables environnementales délétères entraîne une inflammation ainsi que des déficiences moléculaires et cellulaires qui compromettent sa fonctionnalité, ses qualités esthétiques et son bien­être général. La mise en œuvre de l'administration topique d'antioxydants et d'autres composés comme méthode de prévention ou d'inversion des dommages est une approche rationnelle. De nombreux composés phénoliques dérivés de plantes ont démontré des capacités telles que l'élimination des radicaux libres et la promotion de la cicatrisation des tissus. Cependant, le principal obstacle réside dans l'administration efficace de ces composés à un endroit spécifique de la peau, et une prévision précise de leur diffusion a travers la peau peut aider à déterminer les tactiques les plus efficaces. Par conséquent, cet article fournit une analyse complète de la littérature récente concernant les caractéristiques de diffusion cutanée in vitro des composés phénoliques végétaux. L'objectif est de mieux comprendre leur comportement lorsqu'ils sont présents sous diverses formes telles que solutions, suspensions et formulations. MÉTHODES: Les données sur les extraits de plantes et les composés phénoliques végétaux isolés in vitro par diffusion cutanée, publiées au cours des six dernières années, ont été compilées et discutées. RÉSULTATS: Même si la cellule de diffusion Franz de référence est la plus couramment utilisée dans l'évaluation des profils de diffusion cutanée phénoliques végétales in vitro, une pléthore de modelés de peau et de conditions d'analyse sont rapportées pour une variété de composés et d'extraits dans différents véhicules. CONCLUSION: La présence de nombreux modèles et véhicules pose un défi dans la création de corrélations entre les données existantes sur les composés phénoliques végétaux. Cependant, il est possible de tirer des conclusions générales concernant les caractéristiques moléculaires du véhicule et de la peau sur la base des informations recueillies.

What defines dry skin? Correlating a range of skin hydration parameters with In Vivo Confocal Raman Spectroscopy.

OBJECTIVE: While there are a wide range of approaches for the assessment of skin hydration, it is not always clear how data from them relate to one another or to the skin itself. With the development of in vivo Confocal Raman Spectroscopy (ICRS), it has become possible to measure water concentration as a function of protein/depth within the stratum corneum (SC). This article reports a comparison between electrical skin hydration measures/visual/optical grading and water concentration profiles measured using ICRS, to better understand the relationship between these approaches. METHODS: SC hydration of lower-leg skin with varying degrees of dryness was assessed using visual grading (live and from digital images), Corneometer®, Visioscan and ICRS. In addition, a custom fingerprint sensor was used to image surface capacitance (as a surrogate of SC hydration), and SC barrier function was assessed using evaporimetry (to measure trans-epidermal water loss; TEWL). RESULTS: Significant correlations were observed between a number of different skin grading/measurement approaches and ICRS data. ICRS hydration profiles also revealed a region near the SC surface with a relatively flat water profile in dry skin subjects. CONCLUSIONS: The advent of quantitative in vivo analytical techniques such as ICRS, which can be used in a clinical setting, has enabled greater insight into more conventional approaches for assessing skin dryness. While traditional skin grading and biophysical methods for measuring skin hydration have varying degrees of correlation with one another, they also provide comparatively unique information about different regions within the SC. This should enable a more informed approach to product development in the future.

OBJECTIF: Bien qu'il existe un large éventail d'approches pour évaluer l'hydratation de la peau, la façon dont les données qui en résultent sont liées les unes aux autres ou à la peau elle­même n'est pas toujours claire. Avec le développement de la spectroscopie Raman confocale in vivo (ICRS), il est devenu possible de mesurer la concentration en eau en fonction du rapport protéine/profondeur au sein de la couche cornée (stratum corneum, SC). Cet article rapporte une comparaison entre les mesures électriques ou la classification visuelle/optique de l'hydratation de la peau et les profils de concentration en eau mesurés à l'aide de l'ICRS, afin de mieux comprendre la relation entre ces approches. MÉTHODES: L'hydratation du SC de la peau de la partie inférieure de la jambe avec différents degrés de sécheresse a été évaluée à l'aide d'une classification visuelle (en direct et à partir d'images numériques), du Corneometer®, du Visioscan et de l'ICRS. En outre, un capteur d'empreintes digitales personnalisé a été utilisé pour visualiser la capacité de surface (en tant que substitut de l'hydratation du SC) et la fonction de barrière du SC a été évaluée par évaporimétrie (pour mesurer la perte d'eau transépidermique ; trans­epidermal water loss, TEWL). RÉSULTATS: Des corrélations significatives ont été observées entre un certain nombre d'approches différentes de classification/mesure de la peau et les données ICRS. Les profils d'hydratation de l'ICRS ont également révélé une région près de la surface du SC ayant un profil d'eau relativement plat chez les sujets atteints de sécheresse cutanée. CONCLUSIONS: L'avènement de techniques d'analyse in vivo quantitatives telles que l'ICRS, qui peut être utilisée dans un contexte clinique, a permis de mieux comprendre les approches plus conventionnelles d'évaluation de la sécheresse cutanée. Bien que les méthodes traditionnelles de classification de la peau et les méthodes biophysiques de mesure de l'hydratation de la peau présentent des degrés de corrélation variables entre elles, elles fournissent également des informations comparativement uniques sur différentes régions au sein du SC. Cela devrait permettre une approche plus éclairée du développement de produits à l'avenir.

Chemical bonds and hair behaviour-A review.

When undertaking any review of the structure of the hair and its mechanical properties it becomes apparent that the overall behaviour of keratin fibres is commonly attributed to the presence of hydrogen, disulfide and ionic bonds. The action of physico-chemical agents used during various cosmetic treatments is viewed as the result of an interaction with these bonds. Thus, the breaking of bonds by chemical agents, or via mechanical or thermal stresses, affects the relative balance of disulfide and hydrogen bonds and the contribution of hydrophobic interactions, which are all important factors that may alter hair behaviour. Generally, these chemical bonds are considered as responding homogeneously to the environmental and cosmetic factors. This unitary image is challenged, however, by evaluating the results of chemical, nanomechanical, tensile and thermal measurements, which suggest that disulfide bonds may be grouped into several types, according to their location within the fibre and the way they respond to various agents. A compensatory effect of newly formed hydrogen bonds for broken disulfide bonds may also be seen, and additionally involves different types of hydrogen bonds. As a result, the picture of chemical bonding in hair appears to be far from a homogeneous one. In addition, it is apparent that further investigation is required for clarifying the action of ionic bonds and hydrophobic interactions within the hair fibre. The present review aims, thus, at offering a deeper background for understanding how the hair behaves under various conditions.

Comme l'indique l'étude de la littérature réalisée dans le cadre de cette revue, le comportement général des fibres kératiniques est généralement attribué à la présence de liaisons hydrogène, disulfure et ioniques. L'action des agents physico­chimiques utilisés au cours de divers traitements cosmétiques est alors considérée comme le résultat d'une interaction avec ces liaisons. Ainsi, la rupture des liaisons par des agents chimiques, ou par des contraintes mécaniques ou thermiques, affecte l'équilibre relatif des liaisons disulfure et hydrogène et la contribution des interactions hydrophobes, qui sont autant de facteurs importants susceptibles d'altérer le comportement du cheveu. En général, on considère que ces liaisons chimiques réagissent de manière homogène aux facteurs environnementaux et cosmétiques. Cette image unitaire est toutefois remise en question par l'évaluation des résultats des mesures chimiques, nanomécaniques, thermiques et de traction, qui suggèrent que les liaisons disulfures peuvent être regroupées en plusieurs types, en fonction de leur emplacement dans la fibre et de la manière dont elles réagissent aux différents agents. Un effet compensatoire des liaisons hydrogène nouvellement formées pour les liaisons disulfures rompues peut également être observé et implique en outre différents types de liaisons hydrogène. Par conséquent, l'image de la liaison chimique dans les cheveux est loin d'être homogène. En outre, il est évident que des recherches supplémentaires sont nécessaires pour clarifier l'action des liaisons ioniques et des interactions hydrophobes au sein de la fibre capillaire. La présente étude vise donc à offrir une base pour une compréhension plus approfondie du comportement du cheveu dans diverses conditions.

Allergens grouping names on packaging: Are the substances similar enough to ensure safety? The worst case scenarios question this.

OBJECTIVE: European Commission Regulation (EU) n°2023/1545 introduced the concept of grouping names in the cosmetics sector in July 2023. These groups bring together allergenic substances with the same level of skin sensitization. Their purpose is to lighten the list of ingredients on cosmetic packaging, by grouping together substances deemed to be similar under the same name. As this classification is based on a single toxic effect - skin sensitization - the present study aims to analyse the relevance of these groupings with regard to other toxic effects of substances in the same group. METHODS: This study was carried out by consulting an available database, various reports from 5 committees, 2 books and 5 articles in order to complete the toxicological profile of each substance. Then, in order to highlight any discrepancies within the classification, the worst cases were identified. For this purpose, the data for each substance in a group were compared, and in the event of greater criticality for a toxic effect, this was qualified as a worst case. In addition, similar toxic effects between several substances within the same group were also recorded. The aim of this additional research was to validate the definition of the grouping name and the similarities between substances in the same group. RESULTS: From the 17 grouping names, 5 presented worst cases. Two groups had 2 worst cases and the others only one. In total, from the 7 worst cases detected, 3 were due to the toxic effect "skin irritation". In most cases, the substances in the groupings shared the presence or absence of risk. Only the degree of risk criticality varied. CONCLUSION: Classification by grouping names appears justified regarding the similarities between substances, particularly in terms of skin sensitization. However, the presence of worst cases qualifies it and highlights the importance of being vigilant when assessing the risk of cosmetic products including these grouping names in their list of ingredients.

OBJECTIF: Le règlement (UE) n°2023/1545 de la Commission européenne a introduit la notion de « grouping names ¼ dans le domaine des cosmétiques en juillet 2023. Ces groupes rassemblent des substances allergènes ayant le même niveau de sensibilisation cutanée. Ils ont pour objectif d'alléger la liste des ingrédients figurant sur les emballages des produits cosmétiques, en regroupant sous un même nom des substances jugées similaires. Cette classification étant fondée sur un seul effet toxique ­ la sensibilisation cutanée ­ la présente étude vise à analyser la pertinence de ces regroupements au regard des autres effets toxiques des substances d'un même groupe. MÉTHODES: Cette étude a été réalisée en consultant une base de données disponible, différents rapports de 5 comités, 2 livres et 5 articles afin de compléter le profil toxicologique de chaque substance. Ensuite, afin de mettre en évidence les divergences au sein de la classification, les cas de criticité plus importante ont été identifiés. Pour ce faire, les données de chaque substance d'un groupe ont été comparées, et en cas de criticité supérieure d'un effet toxique, celui­ci a été qualifié de « worst case ¼. En outre, les effets toxiques similaires entre plusieurs substances d'un même groupe ont également été enregistrés. L'objectif de cette recherche complémentaire était de valider la définition du « grouping name ¼ et les similitudes entre les substances d'un même groupe. RÉSULTATS: Sur les 17 « grouping names ¼, 5 présentaient des « worst cases ¼. Deux groupes présentaient deux « worst cases ¼ et les autres un seul. Au total, sur les 7 « worst cases ¼ détectés, 3 étaient dus à l'effet toxique "irritation cutanée". Dans la plupart des cas, les substances des groupes partagent la présence ou l'absence de risque. Seul le degré de criticité du risque variait. CONCLUSION: La classification par « grouping names ¼ semble justifiée au regard des similitudes entre les substances, notamment en termes de sensibilisation cutanée. Cependant, la présence de « worst cases ¼ la nuance et souligne l'importance d'être vigilant lors de l'évaluation du risque des produits cosmétiques incluant ces « grouping names ¼ dans leur liste d'ingrédients.

Spectral histology of hair and hair follicle using infrared microspectroscopy.

OBJECTIVE: Today, there is only limited knowledge of the spatial organization of hair chemistry. Infrared microspectroscopy is a well-established tool to provide such information and has significantly contributed to this field. In this study, we present new results combining multiple infrared microspectroscopy methods at different length scales to create a better chemical histology of human hair, including the hair follicle, hair shaft, hair medulla and hair cuticle. METHODS: We used hyperspectral IR imaging & spectroscopy (HIRIS) and synchrotron-radiation FTIR microspectroscopy (SR-µFTIR) to measure transversal hair sections and SR-µFTIR to obtain high-resolution maps of longitudinal sections from the hair shaft and from the hair follicle. We used optical photothermal IR microspectroscopy (OPTIR) to analyse the cuticle surface of intact hairs. RESULTS: By mapping longitudinal sections of the human hair follicle with confocal SR-µFTIR, we report the first demonstration of glycogen presence in the outer root sheath of the hair follicle by spectroscopy, and its quantification at the micron scale. Spectral maps, combined with machine learning-based analysis, enabled us to differentiate the various layers of the hair follicle and provided insights into the chemical changes that occur during hair formation in the follicle. Using HIRIS and SR-µFTIR to analyse the hair medulla in transversal sections of human hairs, we report here, for the first time by vibrational spectroscopy methods, the detection of unsaturated lipids at very low concentrations in the medulla. By analysing longitudinal sections of the hair shaft with SR-µFTIR, we found that calcium carboxylates are present in large regions of the hair cuticle, and not just in small focal areas as previously thought. We then use OPTIR to analyse the hair cuticle of intact hairs at submicron resolution without sectioning and report the distribution of calcium carboxylates at the surface of intact hair for the first time. CONCLUSION: These new findings illustrate the potential of infrared microspectroscopy for imaging the chemical composition of human hair and may have implications for biomedical research or cosmetology.

OBJECTIF: Aujourd'hui, les connaissances sur l'organisation spatiale de la chimie capillaire sont limitées. La microspectroscopie infrarouge est un outil bien établi pour fournir de telles informations et a largement contribué à ce domaine. Dans cette étude, nous présentons de nouveaux résultats combinant plusieurs méthodes de microspectroscopie infrarouge à différentes échelles de longueur pour créer une meilleure histologie chimique des cheveux humains, y compris le follicule pileux, la tige pilaire, la moelle pilaire et la cuticule pilaire. MÉTHODES: Nous avons utilisé l'imagerie et la spectroscopie hyperspectrales infrarouges (Hyperspectral IR Imaging & Spectroscopy, HIRIS) et la microspectroscopie IRTF par rayonnement synchrotron (synchrotron­radiation FTIR microspectroscopy, SR­µFTIR) pour mesurer des coupes transversales de cheveux, et la SR­µFTIR pour obtenir des cartes à haute résolution des coupes longitudinales de la tige pilaire et du follicule pileux. Nous avons utilisé la microspectroscopie photothermique infrarouge optique (Optical Photothermal IR microspectroscopy, OPTIR) pour analyser la surface des cuticules de cheveux intacts. RÉSULTATS: En cartographiant les coupes longitudinales du follicule pileux humain avec la SR­µFTIR confocale, nous rapportons la première démonstration par spectroscopie de la présence de glycogène dans la gaine de la racine externe du follicule pileux, et sa quantification à l'échelle du micron. Les cartes spectrales, combinées à une analyse basée sur l'apprentissage automatisé, nous ont permis de différencier les différentes couches du follicule pileux et de mieux comprendre les changements chimiques qui surviennent pendant la formation des cheveux dans le follicule. En utilisant la méthode HIRIS et la SR­µFTIR pour analyser la moelle pilaire dans les coupes transversales des cheveux humains, nous rapportons ici, pour la première fois par des méthodes de spectroscopie vibrationnelle, la détection de lipides insaturés à de très faibles concentrations dans la moelle. En analysant les coupes longitudinales de la tige pilaire par SR­µFTIR, nous avons constaté que les carboxylates de calcium sont présents dans de vastes régions de la cuticule pilaire, et pas seulement dans de petites zones focales comme on le pensait auparavant. Nous utilisons ensuite la méthode OPTIR pour analyser la cuticule pilaire de cheveux intacts à une résolution inférieure au micron sans sectionner les cheveux et rapportons pour la première fois la distribution des carboxylates de calcium à la surface des cheveux intacts. CONCLUSION: Ces nouveaux résultats illustrent le potentiel de la microspectroscopie infrarouge pour l'imagerie de la composition chimique des cheveux humains et peuvent avoir des implications pour la recherche biomédicale ou la cosmétologie.

Fermented tea leave extract against oxidative stress and ageing of skin in vitro and in vivo.

OBJECTIVE: The objective is to develop a natural and stable anti-oxidative stress and anti-ageing ingredient. In this study, we evaluated the changes in white tea leaves fermented with Eurotium cristatum PLT-PE and Saccharomyces boulardii PLT-HZ and their efficacy against skin oxidative stress. METHODS: We employed untargeted metabolomics technology to analyse the differential metabolites between tea extract (TE) and fermented tea extract (FTE). In vitro, using H2O2-induced HaCaT cells, we evaluated cell vitality, ROS, and inflammatory factors (TNF-α, IL-1ß, and IL-6). Additionally, we verified the effects on the extracellular matrix and nuclear DNA using fibroblasts or reconstructed skin models. We measured skin hydration, elasticity, wrinkle area, wrinkle area ratio, erythema area, and erythema area ratio in volunteers after using an emulsion containing 3% FTE for 28 and 56 days. RESULTS: Targeted metabolomics analysis of white tea leaves yielded more than 20 differential metabolites with antioxidant and anti-inflammatory activities, including amino acids, polypeptides, quercetin, and liquiritin post-fermentation. FTE, compared to TE, can significantly reduce reactive oxygen species (ROS) and protect against oxidative stress-induced skin damage in H2O2-induced HaCaT cells. FTE can inhibit H2O2-induced collagen degradation by suppressing the MAPK/c-Jun signalling pathway and can also mitigate the reactive oxygen species damage to nuclear DNA. Clinical studies showed that the volunteers' stratum corneum water content, skin elasticity, wrinkle area, wrinkle area ratio, erythema area, and erythema area ratio significantly improved from the baseline after 28 and 56 days of FTE use. CONCLUSION: This study contributes to the growing body of literature supporting the protective effects against skin oxidative stress and ageing from fermented plant extracts. Moreover, our findings might inspire multidisciplinary efforts to investigate new fermentation techniques that could produce even more potent anti-ageing solutions.

OBJECTIF: L'objectif est de développer un ingrédient naturel et stable contre le stress oxydatif et anti­âge. Dans cette étude, nous avons évalué les modifications dans les feuilles de thé blanc fermentées avec la PLT­PE Eurotium cristatum et la PLT­HZ Saccharomyces boulardii et leur efficacité contre le stress oxydatif cutané. MÉTHODES: Nous avons utilisé une technologie de métabolomique non ciblée pour analyser les métabolites différentiels entre l'extrait de thé (ET) et l'extrait de thé fermenté (ETF). In vitro, à l'aide de cellules HaCaT induites par l'H2O2, nous avons évalué la vitalité cellulaire, les ERO et les facteurs inflammatoires (TNF­α, IL­1ß, and IL­6). Nous avons également vérifié les effets sur la matrice extracellulaire et l'ADN nucléaire à l'aide de fibroblastes ou de modèles cutanés reconstruits. Nous avons mesuré l'hydratation de la peau, l'élasticité, la surface de rides, le rapport des surfaces de rides, la surface d'érythème, et le rapport des surfaces d'érythème chez des volontaires ayant utilisé une émulsion contenant 3% d'ETF pendant 28 et 56 jours. RÉSULTATS: L'analyse métabolomique ciblée des feuilles de thé blanc a révélé plus de 20 métabolites différentiels ayant des activités antioxydantes et anti­inflammatoires, notamment des acides aminés, des polypeptides, de la quercétine et de la liquiritine après fermentation. Par rapport à l'ET, l'ETF peut réduire significativement les espèces réactives de l'oxygène (ERO) et protéger contre les lésions cutanées induites par le stress oxydatif dans les cellules HaCaT induites par l'H2O2. L'ETF peut inhiber la dégradation du collagène induite par l'H2O2 en supprimant la voie de signalization MAPK/c­Jun et peut également atténuer les dommages causés par les espèces réactives de l'oxygène à l'ADN nucléaire. Les études cliniques ont montré que la teneur en eau de la couche cornée des volontaires, l'élasticité de la peau, la surface de rides, le rapport des surfaces de rides, la surface d'érythème et le rapport des surfaces d'érythème se sont significativement améliorés par rapport à la référence après 28 et 56 jours d'utilisation d'ETF. CONCLUSION: Cette étude contribue au corpus croissant de littérature soutenant les effets protecteurs des extraits de plantes fermentées contre le stress oxydatif cutané et le vieillissement. En outre, nos résultats pourraient inspirer des efforts pluridisciplinaires pour étudier de nouvelles techniques de fermentation susceptibles de produire des solutions anti­âge encore plus puissantes.

Melanosomal localization is required for GIF-2115/2250 to inhibit melanogenesis in B16F10 melanoma cells.

OBJECTIVE: Tyrosinase inhibitors suppress melanogenesis in melanocytes. During a screening for tyrosinase inhibitors, however, we noticed some discrepancies in inhibitory efficacies between melanocytes and in vitro assays. The compound (S)-N-{3-[4-(dimethylamino)phenyl]propyl}-N-methyl-indan-1-amine (GIF-2115) exerts antioxidative stress activity upon accumulation in late endosomes and lysosomes. GIF-2115 was also identified as a potent antimelanogenic reagent in B16F10 mouse melanoma cells. GIF-2115 inhibited the activity of mushroom tyrosinase and the lysates of B16F10 cells. However, structure-activity relationship studies indicated that GIF-2238, which lacks the benzene ring in the aminoindan structure of GIF-2115, inhibited tyrosinase activity in vitro but did not inhibit melanogenesis in B16F10 cells. The aim of the present study is to show the importance of the intracellular distribution of tyrosinase inhibitors in exerting their antimelanogenic activity in melanocytes. METHODS: The intracellular distribution of compounds was monitored by linking with the fluorescent group of 7-nitro-2,1,3-benzoxadiazole (NBD). To mislocalize GIF-2115 to mitochondria, the mitochondria-preferring fluoroprobe ATTO565 was used. RESULTS: We reconfirmed the localization of GIF-2250 (GIF-2115-NBD) not only to matured but also to early-stage melanosomes. Although GIF-2286 (GIF-2238-NBD) maintained tyrosinase inhibitory activity, it did not show specific intracellular localization. Moreover, when GIF-2115 was linked with ATTO565, the resultant compound GIF-2265 did not inhibit melanogenesis in B16F10 cells, despite its strong tyrosinase inhibitory activity. CONCLUSION: These results suggest that melanosomal localization is essential for the antimelanogenic activity of GIF-2115, and GIF-2115 derivatives may be new guides for drugs to endosomes and lysosomes as well as melanosomes.

OBJECTIF: Les inhibiteurs de la tyrosinase suppriment la mélanogenèse dans les mélanocytes. Lors d'un criblage d'inhibiteurs de la tyrosinase, cependant, nous avons remarqué des différences dans les efficacités inhibitrices entre les mélanocytes et les essais in vitro. Le composé (S)­N­{3­[4­(diméthylamino)phényl]propyl}­N­méthyl­indan­1­amine (GIF­2115) exerce une activité antioxydante en cas de stress lors de l'accumulation dans les endosomes tardifs et les lysosomes. GIF­2115 a également été identifié comme un puissant réactif antimélanogène dans les cellules de mélanome murin B16F10. GIF­2115 a inhibé l'activité de la tyrosinase de champignon et les lysats des cellules B16F10. Cependant, des études de relation structure­activité ont indiqué que GIF­2238, à qui il manque l'anneau benzénique dans la structure aminoindan de GIF­2115, inhibait l'activité de la tyrosinase in vitro mais n'inhibait pas la mélanogenèse dans les cellules B16F10. L'objectif de la présente étude est de montrer l'importance de la distribution intracellulaire des inhibiteurs de la tyrosinase dans l'exercice de leur activité antimélanogène dans les mélanocytes. MÉTHODES: La distribution intracellulaire des composés a été surveillée en les liant au groupe fluorescent de la 7­nitro­2,1,3­benzoxadiazole (NBD). Pour délocaliser GIF­2115 vers les mitochondries, le fluorophore ATTO565 préférant les mitochondries a été utilisé. RÉSULTATS: Nous avons confirmé la localisation de GIF­2250 (GIF­2115­NBD) non seulement dans les mélanosomes matures mais aussi dans les mélanosomes à un stade précoce. Bien que GIF­2286 (GIF­2238­NBD) ait maintenu une activité inhibitrice de la tyrosinase, il n'a pas montré de localisation intracellulaire spécifique. De plus, lorsque GIF­2115 a été lié à ATTO565, le composé résultant GIF­2265 n'a pas inhibé la mélanogenèse dans les cellules B16F10, malgré son activité inhibitrice de la tyrosinase forte. CONCLUSION: Ces résultats suggèrent que la localisation dans les mélanosomes est essentielle pour l'activité antimélanogène de GIF­2115, et que les dérivés de GIF­2115 peuvent être de nouveaux guides pour les médicaments vers les endosomes et les lysosomes ainsi que les mélanosomes.

Assessing residual fragrances on skin after body washing: Optimization of an analytical method using solid-phase microextraction coupled with gas chromatography-mass spectrometry.

OBJECTIVE: The aim of this study is to develop and optimize a method for evaluating the persistence of residual fragrance after body washing, addressing a significant requirement in the development of personal care products. The main objective is to establish a reliable, sensitive and reproducible analytical technique to assess fragrance longevity on skin post-use of body wash products. METHODS: Headspace solid-phase microextraction (HS-SPME) coupled with gas chromatography-mass spectrometry (GC-MS) is used to analyse residual fragrances. We investigate the extraction efficiencies of various SPME fibres and compare different methods for sampling skin-emitted fragrances, including tape stripping and sealed glass funnels. A controlled body-washing procedure is implemented to standardize the cleansing process. RESULTS: Our findings indicate that the relative standard deviation for measuring five distinct fragrances is within the range of 3%-14%, highlighting the precision of the method. A notable variance exists in the extraction efficiency of fragrances using different types of SPME fibres, with some exhibiting over a threefold difference. Furthermore, the glass funnel method for fragrance collection demonstrates an 11.7 times greater sensitivity to galaxolide than that of the tape-stripping method. Residual fragrances with base notes as the main components can be detected on the skin up to 24 h after body washing. CONCLUSION: The optimized method for residual fragrance evaluation developed in this study offers a robust tool for analysing fragrance components persisting on the skin for up to 24 h post-wash. This advancement facilitates a deeper understanding of fragrance longevity in personal care products, enabling comparative analyses between different products.

OBJECTIF: l'objectif de cette étude est de développer et d'optimiser une méthode d'évaluation de la persistance du parfum résiduel après la toilette du corps, répondant à une exigence significative dans le développement de produits de soins personnels. L'objectif principal est d'établir une technique analytique fiable, sensible et reproductible pour évaluer la longévité des parfums sur la peau après utilisation de produits de toilette pour le corps. METHODES: la microextraction en phase solide de l'espace de tête (HS­SPME) couplée à la chromatographie en phase gazeuse­spectrométrie de masse (GC­MS) est utilisée pour analyser les parfums résiduels. Nous étudions l'efficacité de l'extraction de diverses fibres SPME et nous comparons différentes méthodes d'échantillonnage des senteurs émises par la peau, y compris le stripping sur ruban adhésif et les entonnoirs en verre scellés. Une procédure contrôlée de lavage du corps est mise en place pour standardiser le processus de nettoyage. RÉSULTATS: nos résultats indiquent que l'écart­type relatif pour mesurer cinq parfums distincts se situe dans la plage de 3% à 14%, ce qui souligne la précision de la méthode. Une variance notable existe dans l'efficacité d'extraction des parfums utilisant différents types de fibres de SPME, certaines présentant plus d'un triplement de différence. En outre, la méthode de l'entonnoir en verre pour la collecte des parfums démontre une sensibilité au galaxolide 11,7 fois supérieure à celle de la méthode de stripping sur ruban adhésif. Les parfums résiduels avec des notes de fond comme principaux composants peuvent être détectés sur la peau jusqu'à 24 h après le lavage du corps. CONCLUSION: la méthode optimisée pour l'évaluation du parfum résiduel développée dans cette étude offre un outil fiable pour analyser les composants du parfum persistant sur la peau jusqu'à 24 heures après le lavage. Cette avancée offre une meilleure compréhension de la longévité des parfums dans les produits de soins personnels, permettant des analyses comparatives entre les différents produits.

Revolutionizing food science with mass spectrometry imaging: A comprehensive review of applications and challenges.

Food science encounters increasing complexity and challenges, necessitating more efficient, accurate, and sensitive analytical techniques. Mass spectrometry imaging (MSI) emerges as a revolutionary tool, offering more molecular-level insights. This review delves into MSI's applications and challenges in food science. It introduces MSI principles and instruments such as matrix-assisted laser desorption/ionization, desorption electrospray ionization, secondary ion mass spectrometry, and laser ablation inductively coupled plasma mass spectrometry, highlighting their application in chemical composition analysis, variety identification, authenticity assessment, endogenous substance, exogenous contaminant and residue analysis, quality control, and process monitoring in food processing and food storage. Despite its potential, MSI faces hurdles such as the complexity and cost of instrumentation, complexity in sample preparation, limited analytical capabilities, and lack of standardization of MSI for food samples. While MSI has a wide range of applications in food analysis and can provide more comprehensive and accurate analytical results, challenges persist, demanding further research and solutions. The future development directions include miniaturization of imaging devices, high-resolution and high-speed MSI, multiomics and multimodal data fusion, as well as the application of data analysis and artificial intelligence. These findings and conclusions provide valuable references and insights for the field of food science and offer theoretical and methodological support for further research and practice in food science.