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When grapes are exposed to wildfire smoke, certain smoke-related volatile phenols (VPs) can be absorbed into the fruit, where they can be then converted into volatile-phenol (VP) glycosides through glycosylation. These volatile-phenol glycosides can be particularly problematic from a winemaking standpoint as they can be hydrolyzed, releasing volatile phenols, which can contribute to smoke-related off-flavors. Current methods for quantitating these volatile-phenol glycosides present several challenges, including the requirement of expensive capital equipment, limited accuracy due to the molecular complexity of the glycosides, and the utilization of harsh reagents. To address these challenges, we proposed an enzymatic hydrolysis method enabled by a tailored enzyme cocktail of novel glycosidases discovered through genome mining, and the generated VPs from VP glycosides can be quantitated by gas chromatography-mass spectrometry (GC-MS). The enzyme cocktails displayed high activities and a broad substrate scope when using commercially available VP glycosides as the substrates for testing. When evaluated in an industrially relevant matrix of Cabernet Sauvignon wine and grapes, this enzymatic cocktail consistently achieved a comparable efficacy of acid hydrolysis. The proposed method offers a simple, safe, and affordable option for smoke taint analysis.

In pre-disposed individuals, a reprogramming of the hepatic lipid metabolism may support liver cancer initiation. We conducted a high-resolution mass spectrometry based untargeted lipidomics analysis of pre-diagnostic serum samples from a nested case-control study (219 liver cancer cases and 219 controls) within the Alpha-Tocopherol, Beta-Carotene Cancer Prevention (ATBC) Study. Out of 462 annotated lipids, 158 (34.2%) were associated with liver cancer risk in a conditional logistic regression analysis at a false discovery rate (FDR)

A rapid method is developed for the determination of bisphenol A (BPA) in ethanolic extracts by gas chromatography–mass spectrometry (GC–MS). The GC–MS method has acquired reference status in accredited analytical laboratories in identifying contaminant impurities in food and alcohol products. Bisphenol A is used as a monomer in the production of a number of plastics and epoxy resins; in its free form, it can be contained in quantities exceeding the permissible level in food containers. Bisphenol A can accumulate in a human body and cause harmful health effects. The studies were performed on an Agilent 8890 gas chromatograph equipped with a mass selective detector model 5977B and a 30 m long Ultra ALLOY®-5 UA5-30M-0.25F capillary column. Optimal modes for the determination of bisphenol A in ethanolic extracts were selected. The direct determination of BPA in ethyl solutions without derivatization using GC–MS can be recommended for the development of procedures for monitoring the quality and safety of food packaging, monitoring BPA in alcohol-containing liquids, as well as in forensic medical examination as a reference procedure to confirm the reliability of BPA identification. [ABSTRACT FROM AUTHOR]

Summary: This study investigated the effects of reducing sugars and protein‐to‐sugar ratios on generating volatile compounds from nutritional yeast hydrolysates after Maillard reaction. Nutritional yeast extract (NYE) was cleaved using Flavourzyme® at an enzyme‐to‐substrate ratio of 0.5% w/w, followed by heat treatment with varying concentrations of reducing sugars (i.e., hexoses: glucose and fructose and pentoses: xylose and ribose). The results showed that pentoses generate higher numbers and concentrations of volatiles than hexoses, especially furans, Strecker aldehydes, and sulphur‐containing compounds such as dimethyl disulphide. However, hexoses produced higher concentrations of pyrazines. Strecker aldehydes and pyrazines served as key aroma‐active compounds in meat aroma. Likewise, sulphur‐containing compounds played an important role in meat aroma due to their low detection threshold. The results showed that reducing sugars significantly impacts the volatile profile of NYE, potentially influencing the formation of meaty aroma compounds. These findings demonstrate the potential of MRPs to enhance meaty flavours due to the presence of volatile compounds with characteristics of cooked meat. [ABSTRACT FROM AUTHOR]

This work focuses on the profiling of semiochemicals (SCS) from Callosobruchus maculatus, Sitophilus oryzae and Tribolium castaneum by headspace solid-phase microextraction (HS-SPME) coupled with gas chromatography–mass spectrometry (GC–MS) technique. Totally, 6, 9 and 8 volatile compounds (VCS) were detected from C. maculatus, S. oryzae and T. castaneum, respectively. As a result of pherobase analysis and preference bioassay, stearic acid (C. maculatus); nonanal, lauric acid and stearic acid (S. oryzae); stearic acid (T. castaneum) were identified as new SCS that could be useful for integrated pest management (IPM) practices. [ABSTRACT FROM AUTHOR]

Fungicides are an indispensable tool in plant disease control. Various modes of action (MOAs) have been identified in different fungicides to suppress plant pathogens. The combined use of fungicides with distinct MOAs has been recommended to prevent the development of pathogen resistance. In studying MOAs, metabolomics has been proven to be a robust and high-throughput method. Because metabolites are unique and distinct depending on the biological activities of an organism, MOAs can be identified and classified by establishing metabolic fingerprinting and metabolic profiles. Similarly, if fungicide resistance is developed in a pathogen, the metabolome will change, which can be identified. In this review, we have discussed the principles and advanced applications of metabolomics in the study of MOAs and resistance mechanisms of fungicides, and the potential of metabolic data in understanding the interaction between fungicides and pathogens. Challenges are also discussed in the application of metabolomics, improvement of the study on the mechanism of fungicides in their functions against pathogens and advancing the development of novel fungicides. [ABSTRACT FROM AUTHOR]

AbstractIntroductionMethodsResultsDiscussionConclusionsEthion is an organophosphate used as an acaricide and insecticide, that is restricted worldwide. In Colombia, pesticide poisoning is the third most common cause of chemical intoxication. On 9 October 2022, an outbreak of ethion poisoning occurred in Pereira. The aim of this study was to describe the clinical and epidemiological characteristics of the outbreak.This is a descriptive study of an outbreak of organophosphate poisoning. The onset of symptoms occurred on 9 October 2022, following the consumption of empanadas. Information was collected on sociodemographic characteristics and clinical manifestations, as well as from paraclinical examinations. Data were obtained from clinical histories, field epidemiological investigations, and inspection visits. Food samples were collected for analysis by gas chromatography-mass spectrometry. Attack rates, proportions, and measures of central tendency, dispersion, and position were calculated.The case definition was met by 37 individuals with a median age of 30 years; all presented with muscarinic symptoms, 29 patients presented with nicotinic symptoms, and 20 patients presented with neurological symptoms. Males were the most affected (57%), and the most common time of symptom onset was 10:00 am. Twenty-three patients (62%) required intensive care unit admission, of whom 14 (38%) required mechanical ventilation. No deaths were reported. Erythrocyte acetylcholinesterase activity was reduced in all patients. Ethion was detected in mass-prepared maize and empanadas at concentrations greater than 0.1 mg/kg. The consumption of empanadas was identified as the common source.In Colombia, pesticide poisonings are the third most common type of poisoning caused by chemical substances reported to the National Health Institute through the National Public Health Surveillance System. In the present outbreak, ethion was in empanadas, likely due to contamination of cooking oil.We describe a large ethion-contaminated food poisoning outbreak reported in Colombia. The main symptoms were muscarinic, and the main treatment measures employed were atropine and respiratory support. Increased awareness of pesticide poisoning and training for food handlers are needed. [ABSTRACT FROM AUTHOR]

Summary Soaking of soybeans is an essential step in tempe fermentation. Owing to the uncontrolled microflora, spontaneous soaking during tempe production leads to inconsistencies in tempe quality. Common methods to control it include the addition of acids or microbial starters. Despite knowing the benefits, their impact on tempe's composition was less understood. In this study, prior to tempe fungal fermentation, soybeans were soaked with Lactiplantibacillus plantarum NBRC 101978 and Pichia burtonii NBRC 0844. Tempe samples were subjected to comprehensive analysis using a widely targeted gas chromatography–mass spectrometry (GC–MS) metabolomics approach and evaluation of physical characteristics. A total of 100 metabolites of sugars, amino acids, fatty acids, and organic acids were annotated in all samples. Principal component analysis (PCA) explaining 47.6% of the variance showed that microbial interventions led to alterations in the metabolome of all samples, including the accumulation of amino acids in lactic acid bacteria (LAB)‐soaked soybean tempe and tyramine in yeast‐soaked soybean tempe. Unlike chemically added soaked soybean tempe, microbial intervention significantly reduced the relative intensity levels of several sugars by more than twofold. Furthermore, microbial interventions in the tempe‐soaking step significantly elevated the levels of bioactive metabolites more than twofold. The introduction of microbial interventions in the tempe‐soaking step also influences the physical characteristics of the end product. These findings merit further consideration for tempe development and the food industry. [ABSTRACT FROM AUTHOR]

Copyright of Food Research & Development is the property of Food Research & Development Editorial Department and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Background and Aims: Caffeine is a xanthine alkaloid found naturally in plants. Caffeine has cardiotonic and stimulant effects in humans and animals. For this reason, caffeine is on the monitoring list for human sports and is listed as a feed contaminant in horse racing. The aim of this study was to develop a rapid, practical, and specific method for the determination of caffeine in horse urine. Methods: In the new method, the pH of the sample was adjusted by the addition of phosphate buffer, and after solid phase extraction, it was dissolved in methanol before being analysed by gas chromatography mass spectrometry without derivatization. The method was validated according to the European Commission’s 2002/657/EC criteria. Results: The effects of different cartridge brands, pH, and elution solution were determined. Intraday and interday CV% values are 2.8 and 5.2 for the International Residue Limit (IRL), respectively. Five levels (blank, 0.5xIRL, IRL, 1.5xIRL, and 2xIRL) were used in constructing the curve, and the R2 value was greater than 0.99. The analysis run was 11.8 min. The decision limit (CCα) was determined to be 56.7 ng/mL due to IRL. The detection limit of the method was calculated to be 3.3 ng/mL. The method was determined to be robust according to changes in extraction pH, phosphate buffer concentration, centrifugation time, hexane volume in the wash step, different grades of methanol, inlet temperature, and operator. Conclusion: The applicability of the method was demonstrated by analysing positive and negative horse urine samples. Validation parameters showed the method to be selective, specific, and easy to apply. [ABSTRACT FROM AUTHOR]

• Exploring potential medicinal value from production waste of Chinese herbal medicine and realizing its resourceful utilization is an important way to enhance income and alleviate poverty. • Essential oils from the branches, leaves, flowers and fruits of finger citron were studied for composition and antioxidant activity. • Extraction rate and relative content of essential components of young leaf essential oil were high and antioxidant capacity was moderate. • Young leaves could be preferred in the late development of finger citron non-medicinal parts to develop by-products such as finger citron essential oil perfume and fragrance. The finger citron (Citrus medica L.var. sarcodactylis Swingle) is a both medicinal and edible species specified by the China Ministry of Health, It is also a regional medicinal plant grown in Chinaʼs Chongqing Municipality. We explored the utilization value of flower, leaf, and branch resources of non-medicinal sections of finger citron of Chongqing origin and identified variations in its yield, content, and antioxidant activity in essential oils in several organs. From several finger citron organs, essential oils were extracted using ultrasonic-assisted steam distillation, and their essential components were identified using gas chromatography-mass spectrometry (GC–MS). To assess antioxidant properties of various finger citron organs, DPPH free radical scavenging rate, ABTS free radical scavenging rate, and total reducing power of essential oils were determined. A total of 71 chemical components were discovered, and a cluster heat map revealed that d-limonene, Citral, (Z)-3,7-dimethylocta-2,6-dienal, γ-Terpinene, O Cymene, and Ocimene were the most significant components and that their composition and concentration in essential oils of different organs varied substantially, with the average total amount in the four major organs in descending order: branches (79.34 %), leaves (73.40 %), flowers (68.85 %), and dried fruits (55.69 %). Finger citron's non-medicinal sections and organs' essential oils exhibited some level of antioxidant activity. The maximal clearance rate of the final flower group was 19.26 % when the essential oil concentration of each group was 4.0 mg·mL−1 for the assessment of DPPH free radical scavenging activity. DPPH free radical clearance rates of the bud group, initial flower group, full flower group, final flower group, branch group, and young leaf group were significantly different from the medicinal parts dried fruits group (P < 0.05), whereas there was no significant difference in the old leaf group (P > 0.05). When the essential oil concentration of each group was 0.10 mg·mL−1 for the ABTS radical scavenging ability measurement, the bud group had the highest scavenging rate of 32.24 %, and significant differences in the ABTS radical scavenging rates of the bud group, primary flower group, full flower group, final flower group, and branch group were observed when compared to the dried fruits group (P < 0.05). Between the young leaf and old leaf groups, there was no significant difference (P > 0.05). When the essential oil concentration was 3.0 mg·mL−1 for the measurement of overall reduction capacity, the old leaf group's highest absorbance value was 0.310. and the total reduction capacity of the bud group, first flower group, complete flower group, last flower group, branch group, young leaf group, and old leaf group substantially differed from the dried fruits (P < 0.05). This study provides a reference for the formation of "green" concurrent consumption and development of medicinal and non-medicinal elements of Chinese medicinal materials as well as theoretical support for the diverse utilization of finger citron resources. [ABSTRACT FROM AUTHOR]

The list of standard abbreviations for JDS is available at adsa.org/jds-abbreviations-24. Nonstandard abbreviations are available in the Notes. Short-chain fatty acids (SCFA) content in milk may have been underestimated due to the neglect of the esterified SCFA content and the lack of an accurate detection method, especially for C1:0, C2:0, and C3:0 SCFA. In this study, an accurate GC-MS profiling method was established for 10 SCFA. A 2-step esterification, including alkaline saponification (60°C for 30 min) and acid-catalyzed esterification (80°C for 150 min) in water/isopropyl/hexane (1:2:1, volume ratio), was found to be the most suitable for the quantification of esterified and nonesterified SCFA analysis. The validation results demonstrate satisfactory linearity, sensitivity, matrix effects, precision, and accuracy. The recoveries of nonesterified and esterified SCFA ranged from 82.78% to 112.49%, respectively. Human milk is distinguished from cow milk by its higher C1:0 and C2:0 content and lower C4:0 and C6:0 content. This method successfully accomplished qualitative and quantitative estimation of all 10 SCFA in milk, including both nonesterified and esterified SCFA. Furthermore, whether our method is applicable for the determination of SCFA in serum, rumen fluid, and feces remains to be explored. [Display omitted] [ABSTRACT FROM AUTHOR]

BACKGROUND: Barley flour, known to be rich in various phytochemicals, has been demonstrated to improve the technological and nutritional properties of pasta; however, its volatile profile, on which its aromatic properties depend, also plays an important role in the acceptance of barley‐enriched pasta. In the present work, volatile organic compounds (VOCs) of semolina doughs enriched with different percentages of barley and of the related pasta were characterized by solid phase micro‐extraction (HS‐SPME) coupled to gas‐chromatography/mass spectrometry (GC–MS), and evaluated using a multivariate statistical approach, including principal component analysis (PCA), cluster heatmaps, Pearson's and Spearman's correlations, and partial least squares correlation (PLSC). RESULTS: The effects of single raw materials, and their interactions, were studied to establish their importance in the volatile profile of the samples, and the correlation between the dough VOCs and the processed product VOCs was assessed. The presence of barley flour markedly affected the volatile profile in comparison with the dough obtained with only durum wheat. For alcohols, esters, terpenes, and some aldehydes there was a clear correlation with the percentage of barley. For some of the VOCs, on the other hand, a strong dependence on the ingredients interaction effect due to the mixing stage has been demonstrated. CONCLUSION: The heatmaps allowed a good graphical visualization of the relationship between molecules and barley percentage, offering the possibility to select the best one according to the desired volatolomic footprint. Pasta with 40% of barley was demonstrated to give pasta with the most complex volatile profile. © 2024 Society of Chemical Industry. [ABSTRACT FROM AUTHOR]

The growing demand for alternative sources of non-animal proteins has stimulated research in this area. Mushrooms show potential in the innovation of plant-based food products. In this study, the aim was to develop prototype fish fillets analogues from Pleurotus ostreatus mushrooms applying enzymatic treatment (β-glucanase and transglutaminase-TG). A Plackett–Burman 20 experimental design was used to optimize forty variables. Oat flour (OF) exerted a positive effect on the hardness and gumminess texture parameters but a negative effect on cohesiveness and resilience. Soy protein isolate (SPI) exhibited a positive effect on elasticity, gumminess and chewiness, while acacia gum had a negative effect on elasticity, cohesiveness and resilience. After sensory analysis the assay with 1% cassava starch, 5% OF, 5% SPI, 0.1% transglutaminase (240 min/5 °C), 1% coconut oil, 1% soybean oil, 0.2% sodium tripolyphosphate, 0.6% β-glucanase (80 °C/10 min) and without β-glucanase inactivation was found to exhibit greater similarity to fish fillet. The classes hydrocarbons, alcohols and aldehydes are the predominant ones in aromatic profile analysis by chromatography and electronic nose. It is concluded that a mushroom-based analogue of fish fillet can be prepared using enzymatic treatment with TG. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Food Safety & Quality is the property of Journal of Food Safety & Quality Editorial Department and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Science & Technology of Food Industry is the property of Science & Technology of Food Industry Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of China Brewing is the property of China Brewing Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

In response to growing concerns regarding the environmental impact and the development of resistance to synthetic fungicides, researchers have undertaken investigations into natural alternatives for managing plant diseases caused by various fungi. This study investigates the antifungal properties of aqueous extracts and essential oils from Moroccan Rosmarinus officinalis, Origanum compactum, and Origanum majorana leaves against ten phytopathogenic fungi. The essential oils of the plants were extracted by hydrodistillation employing the Clevenger apparatus, and aqueous extracts were obtained through the infusion process. The antifungal efficacy of the extracts was assessed against ten phytopathogenic fungi utilising the poisoned food technique. The chemical composition of the essential oils was determined through GC-MS. Biochemical analyses were conducted to identify the phytochemical compounds responsible for the antifungal efficacy observed in the EOs and aqueous extracts. The essential oil extracts derived from Origanum compactum and Origanum majorana leaves exhibited potent antifungal properties against all tested fungi, with notably low IC50 values. While Rosemary essential oil displayed moderate activity. The aqueous extracts exhibited weak activities against all tested fungal strains. The GC-MS analysis revealed that 1.8-cineole accounted for 49.93% of the essential oil of Rosemary, pulegone (26.79%) of the essential oil of Compact Oregano, and carvacrol (61.66%) of the essential oil of Marjoram. The results of the biochemical analysis have shown that the extracted samples contain important components, specifically polyphenols, flavonoids, saponins, and catechic tannins. This study has showcased the promising potential of essential oils and aqueous extracts derived from Moroccan plants to effectively combat fungal diseases in plants. [ABSTRACT FROM AUTHOR]

Copyright of Food Research & Development is the property of Food Research & Development Editorial Department and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Cervical cancer (CC) remains a major health concern globally, much of the brunt of which is experienced by the low- and middle-income countries where screening in terms of cytology and DNA genotyping for the high-risk oncogenic subtypes of the human papilloma virus (hr-HPV) is either inadequate or performed rather late. In this study, we aimed to determine biomarkers or panels of biomarkers that are capable of diagnosing the precancerous cervical intraepithelial neoplasia (CIN) stages from healthy and CC patients via untargeted gas chromatography–mass spectrometry-based metabolomics. Various cross-comparisons were conducted from which differential metabolites were identified. The underlying metabolic pathways based on the differential metabolites identified from the various cross-comparisons mainly related to amino acids biosynthesis and metabolism and steroid hormone biosynthesis. From all cross-comparisons, two common metabolites namely, 2-methyl-1-propylamine (also known as isobutylamine) and estrone were found to possess excellent to good diagnostic abilities, especially in distinguishing the early stages of CIN (CIN I, CIN II) from healthy women and CC patients. These findings have clinical significance in the sense that, once validated the 2-biomarker panel could be adopted in clinical practice for early diagnosis of CIN and invasive carcinoma. This would therefore inform the choice of treatment to be initiated by the clinician. [ABSTRACT FROM AUTHOR]

Although men's attraction to women's body odour has been suggested to vary over the ovulatory cycle, peaking around the fertile window, we still lack methodologically robust evidence corroborating this effect. Further, the chemical underpinnings of male preference for the odour of ovulating women remain unknown. Here, we combined perceptual and chemical analyses to investigate the axillary odour of naturally cycling women over 10 days, covering the gradual change in fertility across the ovulatory cycle with a focus on fertile days. The fertile state was confirmed by urinary ovulation tests as well as salivary oestradiol and progesterone levels. Men rated the scent of unfamiliar women, resembling a first encounter. We used multivariate analyses to relate variation in both odour ratings and chemical composition to female conception probability, temporal distance to ovulation and ovarian hormone levels. Our results provide no evidence that males prefer the odour of fertile women. Furthermore, the volatile analysis indicated no link between axillary odour composition and current fertility status. Together, our results showed no convincing support for a chemical fertility cue in women's axillary odour, questioning the presence of olfactory fertility information that is recognizable during first encounters in modern humans. [ABSTRACT FROM AUTHOR]

The object of this research is the polychlorinated biphenyls (PCBs) in sediments along Shatt Al-Arab estuary, Iraq. The study examines the problem of river PCB pollution. PCB effects on humans include cancer, impaired reproduction, neuro-developmental effects in infants, immunotoxicity and endocrine disruption. PCBs lead to liver damage and stimulate changes in the DNA sequence. The Shatt Al-Arab Estuary is formed in southern Iraq near Al-Qurna city after the confluence of the Tigris and Euphrates Rivers. The Shatt Al-Arab Estuary region is shared between Iraq and Iran. The Estuary receives pollutants when it is passing during Basrah City regions, due to industrial, agricultural and human activities which discharge the pollutants to the Estuary without treatment. The concentrations of Σ13 PCBs compound in sediment samples were determined and analyzed at each site by using gas chromatography-mass spectrometry (GC-MS, Agilent). Six sites were chosen along Shatt Al-Arab Estuary. They are Al-Qurna (S1), Al-Deer (S2), Al-Qarma (S3), Al-Ashar (S4), Abi Al-Khasib (S5) and Al-Fao (S6), at Basrah city, south of Iraq. Sediment samples were collected seasonally, starting from Autumn season on September 2019 to summer season on July 2020. The Σ13 (PCB-18, PCB-29, PCB-31, PCB-28, PCB-44, PCB-52, PCB-101, PCB-141, PCB-149, PCB-138, PCB-153, PCB-189, and PCB-194) concentrations at the sediment samples ranged from 4.48 ng/g in Al-Deer site during summer season to 27.75 ng/g in Al-Ashar site during winter season for all selected sites. The Al-Deer site were found to have the lowest mean of PCBs its 0.345 ng/g and Al-Ashar site were found to have the highest mean of PCBs its 2.135 ng/g. PCBs concentrations in sediment samples during autumn, winter, spring and summer seasons ranged from 7.75 to 21.68 ng/g, 16.25 to 27.75 ng/g, 7.28 to 22.01 ng/g and 4.48 to 14.41 ng/g, respectively. The congener distribution patterns in these samples indicate the dominance highly chlorinated congeners (tri- and hexa-PCBs) in comparison with remaining others PCBs congeners. This project is the first of its kind in Basrah and all Iraq that reports PCB concentrations in the region and is considered a baseline study and can be used for subsequent studies. [ABSTRACT FROM AUTHOR]

Angomonas deanei belongs to Trypanosomatidae family, a family of parasites that only infect insects. It hosts a bacterial endosymbiont in a mutualistic relationship, constituting an excellent model for studying organelle origin and cellular evolution. A lipidomic approach, which allows for a comprehensive analysis of all lipids in a biological system (lipidome), is a useful tool for identifying and measuring different expression patterns of lipid classes. The present study applied GC-MS and NMR techniques, coupled with principal component analysis (PCA), in order to perform a comparative lipidomic study of wild and aposymbiotic A. deanei grown in the presence or absence of FBS. Unusual contents of branched-chain iso C17:0 and C19:0-cis-9,10 and-11,12 fatty acids were identified in A. deanei cultures, and it was interesting to note that their content slightly decreased at the log phase culture, indicating that in the latter growth stages the cell must promote the remodeling of lipid synthesis in order to maintain the fluidity of the membrane. The combination of analytical techniques used in this work allowed for the detection and characterization of lipids and relevant contributors in a variety of A. deanei growth conditions. [ABSTRACT FROM AUTHOR]

The purpose of this research is to investigate the chemical composition of the essential oils from the flowers, seeds, and leaves of Foeniculum vulgare Mill. collected in southeastern Algeria and to assess their antioxidant and antimicrobial properties. Essential oils were obtained by hydrodistillation and analyzed by gas chromatography-mass spectrometry. The seeds exhibited the highest yield (5.366%). Overall, 93 components have been identified: α-thujene (38.46%), dill ether (12.35%), cosmene (9.43%), sabinene (5.59%), and piperitenone (3.71%) were the major components in leaf essential oil; carvone (27.35%), dill ether (7.22%), 2-hydroxy-1,1,10-trimethyl-6,9-epidioxydecalin (5.67%), and 2,3-pinanediol (4.69%) in flowers; carvone (46.17%), diprene (14.32%), and cis-dihydrocarvone (9.38%) in seeds. For the first time, the antioxidant capacity of isolated oils was assessed by 2,2-diphenyl-1,1-picrirylhydrazil, 2,2′-Azino-bis (3-ethylbenzothiazoline-6-sulfonic acid), and phosphomolybdenum methods. The flower oil showed the highest antiradical ability with inhibitory concentrations at 50% of 14.59 and 22.43 mg/mL, successively. Positive controls, ascorbic acid, and butylated hydroxytoluene showed strong scavenging activity with respective inhibitory concentrations of 50% at 6.42 and 18 µg/mL compared to our oils. Moreover, seed oil possessed the highest power to reduce molybdenum, with an efficient concentration of 0.58 mg/mL. Additionally, the antimicrobial power was measured by observing the size of inhibition zones produced by oils after being diffused onto agar discs. Results showed that the seed and flower oils are very effective against all kinds of bacteria tested, while the leaf oil exhibited a high level of antifungal activity. F. vulgare essential oils can provide a highly promising natural option with potential use in food preservation and healthcare. [ABSTRACT FROM AUTHOR]

Copyright of Shipin Kexue/ Food Science is the property of Food Science Editorial Department and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

This study investigated levels of eight polycyclic aromatic hydrocarbons (PAH8) compounds in both raw and processed marine products in South Korea. Katsuobushi exhibited the highest concentration of benzo[a]pyrene, at 14.22 µg/kg, exceeding the European Commission's regulation level of 5.0 µg/kg. The total PAH8 concentration in katsuobushi was 220.5 µg/kg. Among the product categories, shellfish had the highest detection rate (70%), followed by fish (19%) and crustacea (8%), with chrysene being the most prominent PAH8 congener in all marine products. Grilled fish predominantly contained pyrogenic PAHs from combustion byproducts, while shellfish primarily contained petrogenic ones from the aquatic environment. Grilling, smoking, and drying processes significantly contributed to the formation of PAH8 in these food products. Based on the results of a risk assessment using a margin of exposure approach through a total diet study, exposure to PAH8 from marine products is considered to pose low concern to the South Korean population. [ABSTRACT FROM AUTHOR]

Insect-plant interactions are shaped by the exchange of chemical cues called semiochemicals, which play a vital role in communication between organisms. Plants release a variety of volatile organic compounds in response to environmental cues, such as herbivore attacks. These compounds play a crucial role in mediating the interactions between plants and insects. This review provides an in-depth analysis of plant semiochemicals, encompassing their classification, current understanding of extraction, identification, and characterization using various analytical techniques, including gas chromatography-mass spectrometry (GC-MS), liquid chromatography-mass spectrometry (LC-MS), nuclear magnetic resonance (NMR) spectroscopy, and infrared (IR) spectroscopy. The article also delves into the manner in which insects perceive and respond to plant semiochemicals, as well as the impact of environmental factors on plant odor emission and insect orientation. Furthermore, it explores the underlying mechanisms by which insects perceive and interpret these chemical cues, and how this impacts their behavioral responses, including feeding habits, oviposition patterns, and mating behaviors. Additionally, the potential applications of plant semiochemicals in integrated pest management strategies are explored. This review provides insight into the intricate relationships between plants and insects mediated by semiochemicals, highlighting the significance of continued research in this field to better understand and leverage these interactions for effective pest control. [ABSTRACT FROM AUTHOR]

This research aimed to analyze the impact of two different non-Saccharomyces yeast species on the aromatic profile of red wines made from the cv. Babić (Vitis vinifera L.) red grape variety. The grapes were obtained from two positions in the Middle and South of Dalmatia. This study compared a control treatment with the Saccharomyces cerevisiae (Sc) strain as a type of sequential inoculation treatment with Lachancea thermotolerans (Lt x Sc) and Torulaspora delbrueckii (Td x Sc). The focus was on the basic wine parameters and volatile aromatic compound concentrations determined using the SPME-Arrow-GC/MS method. The results revealed significant differences in cis-linalool oxide, geraniol, neric acid, and nerol, which contribute to the sensory profile with floral and rose-like aromas; some ethyl esters, such as ethyl furoate, ethyl hexanoate, ethyl lactate, ethyl 2-hydroxy-3-methylbutanoate, ethyl 3-hydroxy butanoate, diethyl glutarate, and diethyl succinate, contribute to the aromatic profile with fruity, buttery, overripe, or aging aromas. A sensory evaluation of wines confirmed that Td x Sc treatments exhibited particularly positive aromatic properties together with a more intense fullness, harmony, aftertaste, and overall impression. [ABSTRACT FROM AUTHOR]

This study simplifies the complex relationship among grapevine plants, aphids, ladybirds, and ants, which is essential for effective pest management and ecological balance. This study investigated the impact of aphid attacks and the presence of ants and ladybirds on the volatile compounds profile released into the chemosphere of the community consisting of the common vine Vitis vinifera , the aphid Aphis illinoisensis , the ladybird Coccinella undecimpunctata -and the ant Tapinoma magnum. This study aims to analyze the volatile compounds emitted by the grapevine and surrounding insects in response to these intricate interactions. The extraction of volatile organic compounds (VOCs) was carried out using closed-loop stripping (CLS) and then analyzed via gas chromatography-mass spectrometry (GC-MS) and principles coordinated analysis (PCA) was performed. The grapevine was exposed to different types and order of treatments, including non-infested, aphid-infested, aphid-infested with ant, aphid-infested with ladybird, and various combinations of ant and ladybird. After the aphid attack, the outcomes uncovered massive alterations in the volatile compound profiles. Infested grapevine displayed distinct emissions of germacrene D, an alcohol, and an alkene compared to non-infested plants. The characteristic VOC profile was the share of infested grapes in the presence of ants, with benzene derivatives and sesquiterpenes dominating the components. The coexistence of ladybirds with ants and aphids resulted in a different volatile profile characterized by elevated levels of aldehydes, ketones, α-farnesene, and its hydroxy derivative. It was concluded that the emission of VOCs into the chemosphere of the grapevine communities varied qualitatively and quantitatively depending on the level of the relationship complexity within each community in response to the infestation of grapevines by aphids, the presence of ladybirds as natural predators, and the presence of ant as protector. The grapevine's status-dependent compounds can serve as indicators of infestation status and contribute to non-destructive early-stage diagnosis of the aphid. [ABSTRACT FROM AUTHOR]

Copyright of Food Research & Development is the property of Food Research & Development Editorial Department and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

In this study, an analytical method based on gas chromatography-mass spectrometry (GC-MS) was developed for the simultaneous determination of 8 common psychoactive substances derived from cathinone compounds in tea. Extraction, clean-up and chromatographic and mass spectrometric conditions were optimized. As a result, an alkaline solution containing methanol was selected as the extraction solvent, and the extract was cleaned up on an HLB solid-phase extraction (SPE) cartridge filled with N-propylethylenediamine (PSA) and separated on a DB-17MS capillary column (30 m × 0.25 mm, 0.25 μm). The mass spectrometer was operated using an electrospray ionization (EI) source in the selected ion monitoring (SIM) mode. The calibration curves showed good linearity for the 8 analytes in the concentration range of 0–200 μg/L, with correlation coefficients (r2) higher than 0.998. The limits of detection (LOD, RSN = 3) and limits of quantification (LOQ, RSN = 10) were 7 and 25 μg/kg, respectively. The recoveries from negative samples spiked at 1 ×, 2 × and 10 × LOQ were in the range of 67.2%–117.6%, with relative standard deviations (RSD) of 4.3%–12.3% (n = 6). In summary, this method has good stability and high sensitivity, and is suitable for simultaneous determination of the psychoactive substances derived from cathinones in tea.

In this study, headspace solid phase micro-extraction (HS-SPME) combined with gas chromatography-mass spectrometry (GC-MS) was adopted to separate and identify the volatile components of Kombucha by using polar column DB-WAX. Then, odor activity value (OAV) combined with stoichiometry was used to explore the volatile substance composition and characteristic differential substances of Kombucha in different regions. The results showed that there were significant differences between the volatile substances of Kombucha in different regions. A total of 56 kinds of volatile substances were detected, mainly alcohols, acids, esters and phenols. The OAV results showed that 32 kinds of substances contributed to the flavor for Kombucha (OAV≥1), the OAV of ethyl isovalerate of Kombucha in different regions was highest except for Urumqi and Weihai, it might play an important role in the flavor composition of Kombucha in different regions. Furthermore, with partial least squares discrimination analysis (PLS-DA), 17 variables with importance values greater than 1 as differential markers were identifed. By integrating the results of OAV and PLS-DA, a total of 14 characteristic compounds of Kombucha were screened out, namely 3-methyl-1-butanol, 2-ethyl-1-hexanol, phenethyl alcohol, nonanol, acetic acid, 3-methylbutyric acid, caprylic acid, ethyl acetate, isopentyl acetate, ethyl caprylate, ethyl phenylacetate, furan formaldehyde, 2,6-di-tert-butyl-p-cresol, and 4-ethylphenol. The research results will provide theoretical reference for the standardization, high-quality production and construction of characteristic brands of Kombucha.

This study analyzed and compared the effects of different drying methods on the volatile composition and aroma characteristics of Osmanthus fragrans extract and absolute oil. The volatile composition was determined by gas chromatography-mass spectrometry (GC-MS) and partial least squares-discriminant analysis (PLS-DA), relative odor activity value (ROAV), aroma profile radar and principal component analysis (PCA) were employed to determine the effect of different drying methods on the volatile aroma components of O. fragrans extract and absolute oil. The results showed that a total of 113 volatile components were identified. The types and concentrations of volatile components were significantly different among samples (P < 0.05). Through PLS-DA analysis, 36 volatile marker substances were selected using the cut-off of variable importance in the projection (VIP) score greater than 1, and the accuracy of predictive discrimination of O. fragrans extract and absolute oil prepared by different drying methods was 99.6%. The ROAV and aroma radar plots showed that dihydro-β-ionone, linalool, nonanal, β-ionone, and dihydro-β-iononeone contributed significantly to the aroma of O. fragrans extract and absolute oil, being responsible for the floral, woody, and fruity aromas. Notably, the extract from freeze-dried O. fragrans exhibited a more intense aroma. PCA analysis indicated that freeze-drying contributed to improving the aroma quality of O. fragrans extract and absolute oil. The results of this study provide theoretical support for process optimization and quality improvement of O. fragrans extract products.

An untargeted metabolomic analysis of five Eucalyptus species was used to compare their chemical profiles. Gas chromatography-mass spectrometry (GC-MS) along with multivariate analyses including principal component analysis (PCA) and hierarchical cluster analysis (HCA) were applied to assess variations in the leaf chemical profiles of E. maidenii F. Muell, E. robusta Smith, E. citriodora Hook (syn Corymbia citriodora), E. tereticornis Smith and E. camaldulensis Dehnh. In total, 299 relevant metabolites were identified and subjected to statistical analyses in order to detect either the major common metabolites of the genus or the specific compounds contributing to the characteristic chemical composition of each species. Organic acids, nitrogenous compounds, and phenolic constituents were the main discriminatory groups between the investigated eucalypts. The cluster analysis revealed that fatty acids and fatty alcohols were more concentrated in the leaves of E. citriodora and distinguished it from other species, whereas sugars, polyols, and glycosides were characteristic to E. camaldulensis.

Silver carp (Hypophthalmichthys molitrix) is normally cooked at a high temperature. In order to explore the effects of cooking methods on the protein nutritional values and volatile flavor substances of silver carp meat, the meat was fried, roasted and steamed, and its contents were determined in relation to moisture, protein, fat, ash, amino acids and volatile flavor substances. The results show that the moisture content of cooked silver carp can be ranked as follows: raw > steamed > roasted > fried. The protein content order of the four samples can be ranked: fried > roasted > raw > steamed. The ash and the fat contents of the four samples showed similar significant (p < 0.05) differences, in the order of fried > roasted > steamed > raw. The contents of all the amino acids in the fried meat were significantly (p < 0.05) higher than the contents in others, and the frying, roasting and steaming processes improved the umami taste (supported by the increased content of glutamate and aspartate) and the protein nutritional value (supported by the amino acid score, essential amino acid index and protein efficiency ratio) of the silver carp meat. A total of 51 compounds were detected in the fried, roasted and steamed meat. Frying and roasting reduced the fishy flavor of this meat. The odor activity value (OAV) indicated that methanethiol, 1-octen-3-ol and 2-heptanone were the key flavor chemicals in raw meat. Hexanal, propionaldehyde, octanal, nonanal, decanal, 1-octen-3-ol and 2-heptanone were key to the flavor of fried meat. Pentanal, decanal, methyl mercap-tan and 1-octen-3-ol contributed greatly to the overall flavor of the roasted meat. Nonanal, methylmercaptan and 1-octene-3-ol had strong effects on the flavor of the steamed silver carp meat.

Short-chain fatty acids (SCFAs) are involved in important physiological processes such as gut health and immune response, and changes in SCFA levels can be indicative of disease. Despite the importance of SCFAs in human health and disease, reference values for fecal and plasma SCFA concentrations in healthy individuals are scarce. To address this gap in current knowledge, we developed a simple and reliable derivatization-free GC-TOFMS method for quantifying fecal and plasma SCFAs in healthy individuals. We targeted six linear- and seven branched-SCFAs, obtaining method recoveries of 73–88% and 83–134% in fecal and plasma matrices, respectively. The developed methods are simpler, faster, and more sensitive than previously published methods and are well suited for large-scale studies. Analysis of samples from 157 medically confirmed healthy individuals showed that the total SCFAs in the feces and plasma were 34.1 ± 15.3 µmol/g and 60.0 ± 45.9 µM, respectively. In fecal samples, acetic acid (Ace), propionic acid (Pro), and butanoic acid (But) were all significant, collectively accounting for 89% of the total SCFAs, whereas the only major SCFA in plasma samples was Ace, constituting of 93% of the total plasma SCFAs. There were no statistically significant differences in the total fecal and plasma SCFA concentrations between sexes or among age groups. The data revealed, however, a positive correlation for several nutrients, such as carbohydrate, fat, iron from vegetables, and water, to most of the targeted SCFAs. This is the first large-scale study to report SCFA reference intervals in the plasma and feces of healthy individuals, and thereby delivers valuable data for microbiome, metabolomics, and biomarker research.

Abstract The profiles of polycyclic aromatic hydrocarbons (PAHs) in selected heat-processed meat and fish were evaluated to determine the potential health risk associated with consumption. The samples were analysed using a gas Chromatography-Mass spectrometer. Different concentrations of individual PAHs were detected in the samples, with the smoked samples having the highest concentrations. The total PAHs (mg/kg) in smoked samples were 2.763 ± 0.185 (game meat), 1.618 ± 0.102 (mackerel fish), and 1.718 ± 0.129 (catfish), whereas levels (mg/kg) in grilled samples were 0.771 ± 0.049 (chicken) and 0.911 ± 0.053 (fish). The total carcinogenic PAH (PAH7) concentrations (mg/kg) in grilled chicken and fish and smoked (game meat, mackerel fish, and catfish) samples were 0.231, 0.294, 0.440, 0.309, and 0.332, while their total PAH8 concentrations were 0.356, 0.371, 0.537, 0.465, and 0.476 respectively. The non-carcinogenic PAH risk estimations, both individually (hazard quotient) and cumulatively (hazard index), were below 1 in all the samples. The mean concentrations of PAH markers B[a]P and the PAH4 were above the EU limits in both the smoked and the grilled samples tested. This implies that exposure to high levels of these PAHs through regular consumption of these products may increase the risk of developing certain types of cancer and other health issues. The smoked fishes has the lowest MOE values for the PAH8 compared to the other samples. The margin of exposures (MOEs), carcinogenic toxic equivalent (TEQ), and excess cancer risk (ECR) also indicated that frequent consumption of smoked fish (mackerel or catfish) by an adult of 70 kg body weight above the reported intake rate of 0.0019 kg/AME/day for a prolonged period may have higher cancer risks than in other samples. Smoked game meat had the highest PAH16 level, but indicated a relatively lower risk level, possibly because of its relatively low intake rate (0.0004 kg/AME/day).

Abstract Rice metabolomics is widely used for biomarker research in the fields of pharmacology. As a consequence, characterization of the variations of the pigmented and non-pigmented traditional rice varieties of Tamil Nadu is crucial. These varieties possess fatty acids, sugars, terpenoids, plant sterols, phenols, carotenoids and other compounds that plays a major role in achieving sustainable development goal 2 (SDG 2). Gas-chromatography coupled with mass spectrometry was used to profile complete untargeted metabolomics of Kullkar (red colour) and Milagu Samba (white colour) for the first time and a total of 168 metabolites were identified. The metabolite profiles were subjected to data mining processes, including principal component analysis (PCA), Orthogonal Partial Least Square Discrimination Analysis (OPLS-DA) and Heat map analysis. OPLS-DA identified 144 differential metabolites between the 2 rice groups, variable importance in projection (VIP) ≥ 1 and fold change (FC) ≥ 2 or FC ≤ 0.5. Volcano plot (64 down regulated, 80 up regulated) was used to illustrate the differential metabolites. OPLS-DA predictive model showed good fit (R2X = 0.687) and predictability (Q2 = 0.977). The pathway enrichment analysis revealed the presence of three distinct pathways that were enriched. These findings serve as a foundation for further investigation into the function and nutritional significance of both pigmented and non-pigmented rice grains thereby can achieve the SDG 2.

The effects of different cooking methods (raw, microwave, steaming and frying) on the volatile components of Ctenopharyngodon idella were analyzed by gas chromatography-mass spectrometry, electronic nose technique and sensory evaluation. The results of gas chromatography-mass spectrometry showed that 78 volatiles were detected in 4 cooking methods, mainly olefin, alkanes, aldehydes, esters and other volatile compounds, and the number and content of components in frying methods were higher than those in other processing groups. The electronic nose and principal component analysis showed that, compared with raw fish, the volatiles of fish was closer between steaming and microwave, and fried one had a greater effect on the volatiles. The results of sensory evaluation showed that the fish smell in four treatments all had a certain fishy and grassy taste, but the fried one was mainly manifested in burnt and greasy taste. In addition, the special volatile compounds such as trans, trans-2,4-decenal, 2-furanaldehyde and 2-amyl furan produced during frying give the smell of roast meat, which could cover the off-odor such as fishy and grassy. In summary, the volatiles of Ctenopharyngodon idella were mainly aldehydes and esters, and compared with raw fish, frying had the greatest impact on the volatile components, which could better reduce the fishy off-flavor, the results would provide a theoretical basis for the development of deep processing technology for Ctenopharyngodon idella meat.

Background: The effectiveness of polychemotherapy (PCT) for adrenocortical cancer (ACC) is assessed by imaging tests with the RECIST 1.1 criteria. However, the presence of subclinical tumor foci does not allow for an objective measurement of the true tumor burden. As shown previously, postoperative assessment of the steroid metabolome by gas chromatography-mass spectrometry (GCMS) in ACC patients makes it possible to identify early signs of adrenal steroidogenesis abnormalities and of the recurrence of adrenocortical carcinoma. Aim: To identify biomarkers of response to PCT by GCMS study of the urine steroid profile in ACC patients after surgical resection of the tumor. Materials and methods: Urine steroid profiles were studied by GCMS (Shimadzu GCMS-TQ8050 gas chromatography-mass spectrometer) in 30 ACC patients (stages II, III and IV) after surgery and first line (combination of etoposide, doxorubicin and cisplatin with daily mitotane) and second line (gemcitabine combined with capecitabine and mitotane) PCT. The control group included 25 patients with hormonally inactive adenomas. Results: The response to PCT according to RECIST 1.1 criteria was obtained in 23 patients (Group 1, responders) and in 7 patients ACC progressed under PCT (Group 2, non-responders). In the responders, the urinary excretion of etiocholanolone, pregnanediol and pregnanetriol was lower than in the control group. The non-responders had higher urinary excretion of androgens, progestogens and tetrahydro-11-deoxycortisol (THS), compared to the responders and the control group. The patients with ACC progression under PCT had an increase in 3β,16,20-pregnenetriol (3β,16,20-dP3) levels and a decrease of the 3α,16,20-dP3/3β,16,20-dP3 ratio, compared to those in the PCT responders. The threshold values for urinary excretion of dehydroepiandrosterone (DHEA, ≤ 469 mcg/24h; AUC = 1.0), THS (≤ 223 mcg/24h; AUC = 1.0), and 3β,16,20-dP3 (≤ 130 mcg/24h; AUC = 0.986), as well as the 3α,16,20-dP3/3β,16,20-dP3 ratio (≥ 2.13; AUC = 1.0) had 100% sensitivity and specificity for the assessment of the PCT effectiveness. Conclusion: Different urine steroid profiles were obtained by GCMS in the ACC patients after PCT with and without treatment response. The 100% sensitivity and specificity of the threshold values for urinary excretion of DHEA, THS, 3β,16,20-dP3 and the 3α,16,20-dP3/3β,16,20-dP3 ratio for the assessment of PCT results indicate the potential to use these parameters as biomarkers of response or progression of the disease in the monitoring of PCT effects in ACC patients.

In this study, the volatile compounds of orange juice with different content of orange oil were identified by headspace solid-phase microextraction-gas chromatography-mass spectrometry (HS-SPME-GC-MS), and their sensory quality was analyzed via sensory evaluation. Meanwhile, the stability was investigated by rapid stability analysis instrument. The results showed that the detected aromatic compounds in orange juice increased from 19 to 71 after the addition of orange oil, mainly including terpenes, alcohols, esters, aldehydes, and ketones. With an increment of orange oil, the contents of D-limonene, β-myrcene, α-pinene, linalool, sabinene and decanal were markedly enhanced. Further results showed the key aroma compounds of orange oil were terpenes, alcohols, and aldehydes. Among them orange juice with 0.10% orange oil performed the best of taste and overall flavor. In addition, when the addition of orange oil was higher than 0.10%, the phenomenon of floating and sinking, and severe floating was gradually observed in orange juice, which significantly affected the stability of orange juice. This study reveals the effect of orange oil on the flavor and stability of orange juice, which will provide a reference for the processing of orange juice and the development of orange juice beverage.

Short‐chain fatty acids (SCFAs) are organic acids with carbon atoms less than six, released through fermentation products by intestinal microbiome, having multiple physiological activities. Considering weak acidity and high volatility, derivatization or liquid–liquid extraction is essential, which is time consuming. Headspace‐solid‐phase dynamic extraction (HS‐SPDE) coupled with gas chromatography‐mass spectrometry is automated and effortless to determine SCFAs in rat feces. The extraction procedure is performed by aspirating and discharging the headspace cyclically through a steel needle, coated with an inner polyethylene glycol sorbent. The key parameters of SPDE were optimized including coating type, incubation time and temperature, and number of extraction strokes. Besides, salting‐out was conducted. Then, a method by HS‐SPDE‐GC‐MS was established and validated. It only took 3‐min incubation time, 4.5 min extraction time, and 13 min chromatographic separation in a run. The recovery, linearity, limit of quantification, and stability were evaluated. Then, the proposed method was applied to analyze rat feces including 18 rats with liver injury and 23 normal controls. Mann–Whitney U test indicated that the concentrations of six SCFAs in normal rat feces were higher than those with liver injury. This method provides a choice for fast, solvent‐free, automated, and high‐throughput analysis of SCFAs. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Food Safety & Quality is the property of Journal of Food Safety & Quality Editorial Department and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

In this paper, dispersive micro-solid phase extraction technique was developed for the purpose of extracting and preconcentrating organochlorine pesticide residues in juice samples before their separation and quantitative analysis by gas chromatography-mass spectrometry. A sorbent composed of a silica-supported Fe2O3-modified khat leftover biochar nanocomposite (SiO2-Fe2O3-KLBNC) was implemented in the process. To improve the dispersion of the sorbent in the solution, vortex mixer was employed. Experimental parameters influencing the performance of the method were optimized, and the optimal conditions were established. With these conditions, linear dynamic ranges ranged from 0.003 to 100.0 ng/mL were achieved, with a correlation coefficient (r2) ≥ 0.9981. The limits of detection and quantification, determined by signal-to-noise ratios of 3 and 10, respectively, were found to be in the ranges of 0.001–0.006 ng/mL and 0.003–0.020 ng/mL. Intra- and inter-day precision, values ranging from 0.3–4.8% and 1.7–5.2% were obtained, respectively. The matrix-matched extraction recoveries demonstrated favorable outcomes, falling within the range of 83.4–108.3%. The utilization of khat leftover as an adsorbent in contemporary sample preparation methodologies offers a cost-effective alternative to the currently available, yet expensive, adsorbents. This renders it economically viable, particularly in resource-constrained regions, and is anticipated to witness widespread adoption in the coming future. [ABSTRACT FROM AUTHOR]

Bamboo vinegar is a liquid biomass with a huge yield and complex chemical composition. At present, the relative quantification of bamboo vinegar has been investigated in most studies. To analyze twelve compounds from bamboo vinegar simultaneously, gas chromatography-mass spectrometry and an external standard method were used to develop an analytical method. In this method, chromatographic separations of all compounds were above 1.5. The linear range was between 0.100 and 10.000 mg/L, and the coefficient of determination (R2) was between 0.9981 and 0.9997, indicating a good linear relationship. The limit of detection (LOD) was between 0.004 and 0.780 mg/L; the limit of quantitation (LOQ) was between 0.016 and 3.120 mg/L; the relative standard deviations (RSDs) of instrument precision and method stability were less than 8%; the recovery rate was between 89.25% and 113.77%, and its RSD was between 0.44% and 5.70%. Using this method, fourteen bamboo vinegars and six wood vinegars were analyzed, and it was found that the content of propionic acid, phenol, and 2-methoxyphenol was higher in most samples. In addition, the differences in physicochemical properties between distilled bamboo vinegar and its original solution after atmospheric distillation were investigated. [ABSTRACT FROM AUTHOR]

Introduction: Changes in skin phenotypic characteristics are based on skin tissue. The study of the metabolic changes in skin tissue can help understand the causes of skin diseases and identify effective therapeutic interventions. Objectives: We aimed to establish and optimize a non-targeted skin metabolome extraction system for skin tissue metabolomics with high metabolite coverage, recovery, and reproducibility using gas chromatography/mass spectrometry. Methods: The metabolites in skin tissues were extracted using eleven different extraction systems, which were designed using reagents with different polarities based on sequential solid-liquid extraction employing a two-step strategy and analyzed using gas chromatograph/mass spectrometry. The extraction efficiency of diverse solvents was evaluated by coefficient of variation (CV), multivariate analysis, metabolites coverage, and relative peak area analysis. Results: We identified 119 metabolites and the metabolite profiles differed significantly between the eleven extraction systems. Metabolites with high abundances in the organic extraction systems, followed by aqueous extraction, were involved in the biosynthesis of unsaturated fatty acids, while metabolites with high abundances in the aqueous extraction systems, followed by organic extraction, were involved in amino sugar and nucleotide sugar metabolism, and glycerolipid metabolism. MeOH/chloroform-H2O and MeOH/H2O-chloroform were the extraction systems that yielded the highest number of metabolites, while MeOH/acetonitrile (ACN)-H2O and ACN/H2O-IPA exhibited superior metabolite recoveries. Conclusion: Our results demonstrated that our research facilitates the selection of an appropriate metabolite extraction approach based on the experimental purpose for the metabolomics study of skin tissue. [ABSTRACT FROM AUTHOR]

Estimation of the postmortem interval (PMI), especially the early PMI, plays a key role in forensic practice. Although several studies based on metabolomics approaches have presented significant findings for PMI estimation, most did not examine the effects of ambient temperature. In this study, gas chromatography–mass spectrometry (GC‒MS)‒based metabolomics was adopted to explore the changes in metabolites in the cardiac blood of suffocated rats at various ambient temperatures (5 °C, 15 °C, 25 °C, and 35 °C) from 0 to 24 h after death. Isoleucine, alanine, proline, valine, glycerol, glycerol phosphate, xanthine, and hypoxanthine were found to contribute to PMI in all temperature groups. Hypoxanthine and isoleucine were chosen to establish estimation models (equations) with an interpolation function using PMI as the dependent variable (f(x, y)), relative intensity as the independent variable x, and temperature as the independent variable y. Thereafter, these two models were validated with predictive samples and shown to have potential predictive ability. The findings indicate that isoleucine, alanine, proline, valine, glycerol, glycerol phosphate, xanthine, and hypoxanthine may be significant for PMI estimation at various ambient temperatures. Furthermore, a method to determine PMI based on ambient temperature and PMI-related metabolites was explored, which may provide a basis for future studies and practical applications. [ABSTRACT FROM AUTHOR]

Cuticular waxes are essential for protecting plants from various environmental stresses. Allium fistulosum serves as an excellent model for investigating the regulatory mechanisms underlying cuticular wax synthesis with notable epidermal wax characteristics. A combination of gas chromatography–mass spectrometry (GC–MS) metabolite analysis and transcriptomics was used to investigate variations in metabolites and gene expression patterns between the wild type (WT) and glossy mutant type (gl2) of A. fistulosum. The WT surface had a large number of acicular and lamellar waxy crystals, whereas the leaf surface of gl2 was essentially devoid of waxy crystals. And the results revealed a significant decrease in the content of 16-hentriacontanone, the principal component of cuticular wax, in the gl2 mutant. Transcriptomic analysis revealed 3084 differentially expressed genes (DEGs) between WT and gl2. Moreover, we identified 12 genes related to fatty acid or wax synthesis. Among these, 10 DEGs were associated with positive regulation of wax synthesis, whereas 2 genes exhibited negative regulatory functions. Furthermore, two of these genes were identified as key regulators through weighted gene co-expression network analysis. Notably, the promoter region of AfisC5G01838 (AfCER1-LIKE1) exhibited a 258-bp insertion upstream of the coding region in gl2 and decreased the transcription of the AfCER1-LIKE1 gene. This study provided insights into the molecular mechanisms governing cuticular wax synthesis in A. fistulosum, laying the foundation for future breeding strategies. [ABSTRACT FROM AUTHOR]

The antimicrobial, UV photoprotective and antioxidant capabilities of Spirulina spp. methanolic extracts were determined using Fourier transform infrared spectroscopy (FTIR) and gas chromatographymass spectrometry (GC-MS). Notable compounds were reported to be 5 fatty acid methyl esters, 4-methoxyallocinnamic acid, 2-ethylhexyl esters and bumetrizole. Moreover, these metabolites contained functionalities including hydroxyl, alkyl and carbonyl, as supported by the FTIR result. After 24 h, there was no zone of inhibition in the antibacterial activity as measured by the agar well diffusion method at doses of 30, 50 and 70 g/mL. The ABTS radical scavenging assay revealed that the methanolic Spirulina spp. exhibited an inhibitory concentration of 1,047.91 g/mL for antioxidant activity and SPF values of 0.40, 0.23 and 0.93 were calculated using Mansur's equation for concentrations of 30, 50 and 70 g/mL, respectively. The results of the study showed the potential of cyanobacterial extracts as a bioactive ingredient in cosmetic product development. [ABSTRACT FROM AUTHOR]