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Passive smoking due to environmental tobacco smoke is a serious public health concern because it increases the risk of lung cancer and cardiovascular disease. However, the current status and effect of passive smoking in various lifestyles are not fully understood. In this study, we measured hair nicotine and cotinine levels as exposure biomarkers in non-smokers and assessed the risk from the actual situation of passive smoking in different lifestyle environments. Nicotine and cotinine contents in hair samples of 110 non-smoker subjects were measured by in-tube solid-phase microextraction with on-line coupling to liquid chromatography-tandem mass spectrometry, and self-reported lifestyle questionnaires were completed by the subjects. Nicotine and cotinine were detected at concentrations of 1.38 ng mg−1 and 12.8 pg mg−1 respectively in the hair of non-smokers, with levels significantly higher in subjects who reported being sensitive to tobacco smoke exposure. These levels were also affected by type of food intake and cooking method. Nicotine and cotinine in hair are useful biomarkers for assessing the effects of passive smoking on long-term exposure to environmental tobacco smoke, and our analytical methods can measure these exposure levels in people who are unaware of passive smoking. The results of this study suggest that the environment and places of tobacco smoke exposure and the lifestyle behaviors therein are important for the health effects of passive smoking.

Jiang‐flavor Chinese spirits are one of the four basic liquor types in China. It has thousands of years of history in China and is widely enjoyed because of its unique flavor and broad application. Although Jiang‐flavor Chinese spirits have a unique soy sauce flavor, the associated key compounds and production mechanism remain unknown. To investigate this process, soy sauce flavor‐producing strains were obtained, and their metabolites were evaluated. Using wheat as the fermentation medium, we observed changes in total acid, amino nitrogen, and reducing sugar in three strains of Bacillus cerberus with high yield of tetramethylpyrazine during the fermentation process. The results showed that total acid and amino nitrogen contents increased and reducing sugars decreased in a time‐dependent manner. Additionally, detection of volatile compounds via solid‐phase microextraction and gas chromatography–mass spectrometry that total pyrazine content reached 43.175%, 50.461%, and 45.955% in wheat fermentation medium fermented by strains Q1, Q2, and Q5, respectively, suggesting that this important flavor compound might be related to the flavor of soy sauce. Moreover, we found that fermentation time was an important factor in soy sauce flavor, as volatile compounds were detected at different times by the three strains, with pyrazines not detected before 48 hr and peaking at 50.461% after 144 hr. These results indicated that strain Q2 exhibited optimal fermenting performance and might be useful for fermentation of Jiang‐flavor Chinese spirits. Although Jiang‐flavor Chinese spirits have a unique soy sauce flavor, the associated key compounds and production mechanism remain unknown. To investigate this process, soy sauce flavour‐production strains were obtained, and their metabolites were evaluated.

BACKGROUND AND AIMS: Metabolomic screening studies normally contain thousands of samples with each individual sample being thoroughly analysed for observed differences in multiple compounds. A comparative screen is often employed to narrow down the search field before undertaking an intensive quantitative search. This study optimised the parameters for two solid‐phase microextraction (SPME) fibres recently reported to be optimum for the extraction of aroma compounds from a white wine and to create a validated comparative method with the optimised fibre for future metabolomic wine‐screening studies. METHODS AND RESULTS: The analytical parameters for a 65‐μm divinylbenzene/polydimethylsiloxane (DVB/PDMS) and a 100‐μm polydimethylsiloxane (PDMS) fibre were determined based on salt concentration, sample dilution, extraction time and extraction temperature for an extensive library of aroma compounds at a concentration similar to that found in commercial white wines. After optimisation, the best fibre was selected and a semi‐quantitative high‐throughput method was developed. This method was validated for 34 aroma compounds commonly found in wines, with similar results found in three media (model wine, spiked bag‐in‐box wine and a spiked laboratory‐made wine) thus negating any potential matrix effect found when analysing different wines. CONCLUSIONS: The 65‐μm PDMS/DVB fibre was the best for fermentation bouquet studies, and a newly devised method was developed for semi‐quantitative high‐throughput metabolomic screening studies involving 34 aroma compounds common to white wine fermentation bouquet. SIGNIFICANCE OF THE STUDY: A semi‐quantitative high‐throughput method has been validated in a range of different wine media; it is fast and inexpensive and will find application in wine metabolomic studies as it allows one to narrow down the initial search field before employing the more expensive and time‐consuming, traditional quantitative approach.

Simplifying tedious sample preparation procedures to improve analysis efficiency is a major challenge in contemporary analytical chemistry. Solid phase microextraction (SPME), a technology developed for rapid sample pretreatment, has flexibility in design, geometry, and calibration strategies, which makes it a useful tool in a variety of fields, especially environmental and life sciences. Therefore, it is important to study the coupling between the microfluidic electrospray ionization (ESI) chip integrated with the solid phase microextraction (SPME) module and the electrospray mass spectrometer (MS). In our previous work, we designed a solid phase microextraction (SPME) module on a microfluidic chip through geometric design. However, automation and calibration methods for the extraction process remain unresolved in the SPME on-chip domain, which will lead to faster and more accurate results. This paper discusses the necessity to design a micromixer structure that can produce different elution conditions on the microfluidic chip. By calculating the channel resistances, the microfluidic chip’s integrated module with the micromixer, SPME, and ESI emitters optimize the geometry structure. We propose the annular channel for SPME to perform the resistances balance of the entire chip. Finally, for SPME on a single chip, this work provides a quantitation calibration method to describe the distribution of the analytes between the sample and the extraction phase before reaching the adsorption equilibrium.

BACKGROUND AND AIMS: Many aroma compounds occur as glycosidically bound precursors that do not contribute to fruit/beverage aroma until aglycone release during processing or storage. Existing procedures typically measure glycosidically bound compounds after first isolating the glyocoside fraction. The objectives of this work were to evaluate and develop rapid procedures for measuring glycosidically bound volatiles using direct acid or enzyme hydrolysis of fruit tissues or wine followed by analysis of the free volatiles by headspace solid‐phase microextraction coupled with gas chromatography mass spectrometry. METHODS AND RESULTS: Using a mixture containing free (linalool, ethyl decanoate, β‐ionone) and glycosidically bound standards (n‐octyl‐, n‐dodecyl‐, phenyl‐β‐D‐glucopyranoside), acid hydrolysis released 20–60% of the bound volatiles; significant degradation (>50%) of free volatiles occurred. Enzyme hydrolysis efficiently released glycosidically bound compounds (90–100%) while minimising artefactual changes of the free volatiles and further rearrangements of the aglycones. We also compared direct enzyme hydrolysis with hydrolysis of a glycoside fraction obtained by solid‐phase extraction (SPE). Different SPE columns were not equally effective at retaining glycosides; no column type was effective for all glycosides. CONCLUSIONS: Direct hydrolysis of grape and wine samples (and comparison of volatiles before and after hydrolysis) is a useful approach for measuring ‘aroma potential’ compared with prior SPE isolation of the glycosides. SIGNIFICANCE OF THE STUDY: The method described here provides a rapid tool for characterising changes in glycosidically bound volatiles before and after processing (e.g. winemaking) and as a result of varying fruit maturity and/or other agricultural practices.

BACKGROUND AND AIMS: Solid‐phase microextraction (SPME) is a popular tool for the analysis of volatile compounds of wines. Given the constant introduction of new and improved SPME fibres, an updated study on the appropriateness of various fibre coatings for the extraction and quantification of key aroma compounds in wines is crucial for wine analysis research. This study aims to identify the optimal fibre for the analysis of the most important ‘fermentation bouquet’ aroma compounds found in young white wines through the application of a novel scoring system. METHODS AND RESULTS: Fibre efficiency was determined by coefficients of determination from standard curves in 10% (v/v) ethanol solution. The concentration of the samples within the standard curves was established at twice the average concentration reported in wine as the maximum and then dilutions to 40, 2, 0.8 and 0.04% of this maximum concentration. A novel scoring system provided a thorough analysis of the benefits and disadvantages of the five most common, commercially available fibres recommended for aroma compound analysis and quantification for a library of 38 fermentation bouquet aroma compounds commonly found in finished white wines. CONCLUSIONS: Based on our findings, it is recommended that studies of the fermentation bouquet of wines employ either the 65 μm divinylbenzene/polydimethylsiloxane or the 100 μm polydimethylsiloxane fibres for overall extraction, based on peak symmetry, coefficients of determination of the linear curve and sensitivity. SIGNIFICANCE OF THE STUDY: This study details a novel scoring system that allows determination of the best fibre coating for the analysis of compounds contributing to the fermentation bouquet of white wines by headspace SPME coupled with gas chromatography‐mass spectrometry.

Herbal spices are widely used as food additives not only for their distinct aroma and flavor but rather for their health‐promoting properties. In this study, the chemical profiles of four major masala spices—chaat (CMP), pav‐bhaji (PMP), sambhar (SMP), and tandoori (TMP)—were analyzed using advanced multiplex‐mass spectrometry techniques (HS‐SPME–gas chromatography (GC)–MS and UPLC–MS/MS). A total of 45 aroma compounds were identified, with aldehydes emerging as the dominant constituents in PMP and CMP masalas at 74.7% and 56.1%, respectively, compared with 22.1% in SMP and 21.7% in TMP. Notably, cinnamaldehyde was the major compound, present at 70.1% in PMP, 48.5% in CMP, and 10.7% in SMP. Furthermore, 98 secondary metabolites were annotated, spanning nitrogenous compounds, gingerols, diarylheptanoids, phenolic acids, flavonoids, and saponins. Molecular networking highlighted five key clusters of bioactive compounds, including gingerols, capsaicin derivatives, piper alkaloids, and steroidal saponins. The antimicrobial properties of the masalas were evaluated using vapor phase (VP) and direct assays, revealing broad‐spectrum activity, and PMP exhibited the strongest antibacterial effect with the lowest VP minimum inhibitory concentration (VP‐MIC) values, attributed to cinnamaldehyde richness. The partial least squares (PLS) of identified metabolites against all tested microorganisms indicated that PMP was the most correlated to antimicrobial effect. These findings highlight the potential of masala spices not only as flavoring agents but also as food additives with antimicrobial properties. However, factors, such as batch variations, geographic origin, and processing methods, may affect their consistency and application. Future studies should correlate other biological effects, that is, antioxidant, using same model developed in this study for these species. Four major masala spices, Chaat, Pav Bhaji, Sambhar, and Tandoori, were analyzed using advanced multiplex mass spectrometry techniques. A total of 45 aroma compounds and 98 secondary metabolites were identified. These findings underscore the potential of masala spices not only as flavoring agents but also as potential food additives with antimicrobial properties.

Solid-phase microextraction (SPME) possesses unique features that allow it to be used in analyses that would not be possible with traditional sample-preparation methods. The simplicity of SPME protocols and extraction devices makes it a uniform platform for analyzing biological samples, either via the headspace or in direct immersion mode. Furthermore, flexible probe design enables SPME to be applied to target objects of different sizes, offering analysis on a scale ranging “from single cell to living organs”. SPME microfibers are minimally invasive, which enables them to be applied for the spatial and temporal monitoring of target analytes or to assess changes in the entire metabolome or lipidome. Furthermore, SPME permits the capture of the elusive portion of the metabolome, thus complementing exhaustive methods that are biased towards highly abundant and stable species. Significantly, SPME can be interfaced with analytical instrumentation to create a rapid diagnostic tool. However, despite these advantages, SPME has some limitations that must be well-understood and addressed. This paper presents examples of up-to-date applications of SPME, challenges related to particular studies, and future perspectives regarding the application of SPME in biomedical analysis.

The preparation of samples for instrumental analysis is the most essential and time-consuming stage of the entire analytical process; it also has the greatest impact on the analysis results. Concentrating the sample, changing its matrix, and removing interferents are often necessary. Techniques for preparing samples for analysis are constantly being developed and modified to meet new challenges, facilitate work, and enable the determination of analytes in the most comprehensive concentration range possible. This paper focuses on using metal-organic frameworks (MOFs) as sorbents in the most popular techniques for preparing liquid samples for analysis, based on liquid-solid extraction. An increase in interest in MOFs-type materials has been observed for about 20 years, mainly due to their sorption properties, resulting, among others, from the high specific surface area, tunable pore size, and the theoretically wide possibility of their modification. This paper presents certain advantages and disadvantages of the most popular sample preparation techniques based on liquid-solid extraction, the newest trends in the application of MOFs as sorbents in those techniques, and, most importantly, presents the reader with a summary, which a specific technique and MOF for the desired application. To make a tailor-made and well-informed choice as to the extraction technique.

The aim of the present study was to determine the volatile compounds of three different species of chili peppers, using solid-phase microextraction (SPME) methods in combination with gas chromatography–mass spectrometry (GC-MS). The detection of marker aroma compounds could be used as a parameter to differentiate between species of chili peppers for their detection and traceability in chili pepper food. The sensorial contribution was also investigated to identify the predominant notes in each species and to evaluate how they can influence the overall aroma. Three different pepper species belonging to the Capsicum genus were analyzed: Chinense, Annuum, and Baccatum. A total of 269 volatile compounds were identified in these species of chili peppers. The Capsicum annum species were characterized by a high number of acids and ketones, while the Capsicum chinense and Capsicum baccatum were characterized by esters and aldehydes, respectively. The volatile profile of extra virgin olive oils (EVOOs) flavored with chili peppers was also investigated, and principal component analysis (PCA) and hierarchical cluster analysis (HCA) of the volatile profiles were demonstrated to be a powerful analytical strategy for building a model that highlights the potential of a volatile characterization approach for use in evaluating food traceability and authenticity.