Combined Gas Chromatography-mass Spectrometry Research Articles

Geographical discrimination of Flos Trollii by GC-MS and UHPLC-HRMS-based untargeted metabolomics combined with chemometrics

For centuries, Flos Trollii has been consumed as functional tea and a folk medicine in China's north and northwest zones. The quality of Flos Trollii highly depends on the producing zones. Unfortunately, few studies have been reported on the geographical discrimination of Flos Trollii. This work comprehensively investigated Flos Trollii compounds with an integration strategy combining gas chromatography-mass spectrometry (GC-MS) and ultrahigh-performance liquid chromatography-high resolution mass spectrometry (UHPLC-HRMS) with chemometrics to explore the differences between Flos Trollii obtained from various origins of China. About 71 volatile and 22 involatile markers were identified with GC-MS and UHPLC-HRMS, respectively. Geographical discrimination models were synthetically investigated based on the identified markers. The results indicated that the UHPLC-HRMS coupled with the fisher discrimination model provided the best prediction capability (>97%). This study provides a new solution for Flos Trollii discrimination.

Application of the GC-MS method in combination with preliminary solid phase extraction on a magnetic molecular imprinted polymer for the determination of bisphenol A in soils of various types

A method of gas chromatography-mass spectrometry (GC-MS) in combination with pre-concentration on a sorbent with BPA molecular imprints (dosage of sorbent — 50 mg, sorption time — 10 min, pH — 3, desorption with methanol) is used to determine bisphenol A (BPA). The sorbent extracts about 96% of BPA from aqueous solutions with a single sorption and is characterized by a high imprinting factor reaching 7.1. The samples of soils of urbanized territories, as well as typical chernozems and residual carbonate chernozems outside the large cities of the Voronezh region were studied. The limit of BPA detection was 0.07 μg/kg (in terms of dry soil), the range of the linearity of the calibration graph was 0.3 – 35 μg/kg. Determination of bisphenol is hindered by soil contamination with petroleum products, which can be eliminated by washing with heptane. It has been revealed that pH of soils has a significant effect on the BPA migration of along the soil profile. The concentration curves of the BPA distribution over the soil profile up to a depth of 1 m were plotted. The maximum BPA concentrations in the soils of urbanized territories depend on the contamination of the territory with polymer waste. The maximum BPA concentrations (29.84 μg/kg) were determined at a depth of 20 cm in samples taken near the landfill of municipal solid waste. At other points within the city limits, the maximum concentrations range within 5.38 – 8.77 μg/kg. Outside the city of Voronezh, the mobility of BPA increases in more alkaline typical and residual-calcareous chernozems and significant concentrations of the pollutant were found at a depth of 50 – 80 cm. The developed scheme can be applied to targeted screening and monitoring of the BPA content. The method can be used for BPA determination in soil horizons for various soil types, meteorological conditions (precipitation, annual temperature regime), and contamination of the territory (the presence of unauthorized landfills, MSW landfills, sewage treatment facilities near the sampling point).

Trace analysis of nitrated polycyclic aromatic hydrocarbons based on two-color femtosecond laser ionization mass spectrometry

Nitrated polycyclic aromatic hydrocarbons (nitro-PAHs) are suspected to be highly carcinogenic and mutagenic compounds that are present in the environment. Gas chromatography combined with mass spectrometry (GC-MS) is the most frequently used technique for trace analysis. The electron ionization techniques that are currently used in MS, however, typically do not result in the formation of a molecular ion, thus making the determination of these compounds more difficult. In this study, we report on the use of a compact highly-repetitive (low-pulse-energy) ultraviolet (UV) femtosecond laser as the ionization source in combination with a miniature time-of-flight mass analyzer and a time-correlated ion counting system. The UV laser pulses emitted at 343, 257, and 206 nm were produced by harmonic generations of a femtosecond Yb laser emitting at 1030 nm and were utilized for single-color multiphoton ionization. A combination of the 343-nm and 257-nm pulses was further employed to achieve two-color two-photon ionization. This technique was found to be more useful for sensitive detection and also resulted in the formation of a molecular ion. A pump-and-probe technique using these pulses was examined in a proof-of-concept study to measure the femtosecond lifetimes of the nitro-PAHs separated by GC, providing additional information for use in the characterization of the analyte. The developed technique was applied in the analysis of an authentic sample, an organic solvent extract from diesel exhaust particulates. The nitro-PAHs contained in a standard reference material (SRM1975) were determined on a two-dimensional GC-MS display, suggesting that this technique would be useful for the practical trace analysis of nitro-PAHs in environmental samples.

Analysis of Important Volatile Organic Compounds and Genes Produced by Aroma of Pepper Fruit by HS-SPME-GC/MS and RNA Sequencing.

Pepper is an important condiment, and its aroma affects its commercial value. In this study, transcriptome sequencing and combined headspace solid-phase microextraction and gas chromatography-mass spectrometry (HS-SPME-GC-MS) were used to analyze the differentially expressed genes and volatile organic compounds in spicy and non-spicy pepper fruits. Compared with non-spicy fruits, there were 27 up-regulated volatile organic compounds (VOCs) and 3353 up-regulated genes (Up-DEGs) in spicy fruits. The results of KEGG enrichment analysis of the Up-DEGs combined with differential VOCs analysis showed that fatty acid biosynthesis and terpenoid biosynthesis may be the main metabolic pathways for aroma differences between non-spicy and spicy pepper fruits. The expression levels of the fatty acid biosynthesis-related genes FAD, LOX1, LOX5, HPL, and ADH and the key terpene synthesis gene TPS in spicy pepper fruits were significantly higher than those in non-spicy pepper fruits. The differential expression of these genes may be the reason for the different aroma. The results can provide reference for the development and utilization of high-aroma pepper germplasm resources and the breeding of new varieties.

Analysis of the contribution of koji-making with Z. rouxii on volatile compounds of soy sauce

The co-inoculation fermentation of different microorganisms plays a crucial role in soy sauce fermentation in terms of enriching the composition of the volatile compounds. Therefore, the present study sought to investigate the effect of co-inoculation fermentation of Aspergillus oryzae and Zygosaccharomyces rouxii on the dynamics of volatile compounds in soy sauce using the combination of gas chromatography-mass spectrometry (GC-MS) and multivariate correlation analysis. A total of 124 volatile compounds were identified by A. oryzae and Z. rouxii inoculation alone and co-inoculation, including hydrocarbons, fatty acids, phenols, fatty esters, and benzamides. The content of phenylethyl alcohol, ethyl linoleate, and ethyl palmitate was significantly increased, and the metabolic pathways of multiple volatile compounds were affected in soy sauce inoculated with Z. rouxii. The present study results potentially contribute to the optimization of soy sauce fermentation processes.

Intelligent framework for cannabis classification using visualization of gas chromatography/mass spectrometry data and transfer learning

Introduction: Gas chromatography combined with mass spectrometry (GC/MS) is popular analytical instrumentation for chemical separation and identification. A novel framework for chemical forensics based on the visualization of GC/MS data and transfer learning is proposed.Methods: To evaluate the framework, 228 GC/MS data collected from two standard cannabis varieties, i.e., hemp and marijuana, were utilized. By processing the raw GC/MS data, analytical features, including retention times, mass-to-charge ratios, intensities, and summed ion mass spectra, were successfully transformed into two types of image representations. The GC/MS data transformed images were fed into a pre-trained convolutional neural network (CNN) to develop intelligent classifiers for the sample classification tasks. The effectiveness of several hyper-parameters for improving classification performance was investigated during transfer learning.Results: The proposed analytical workflow could classify hemp and marijuana with 97% accuracy. Furthermore, the transfer-learning-based classifiers were established without requiring big data sets and peak alignment.Discussion: The potential application of the new artificial intelligence (AI)-powered framework for chemical forensics using GC/MS data has been demonstrated. This framework provides unique opportunities for classifying various types of physical evidence using chromatography and mass spectrometry signals.

The Construction of Volatile Profiles of Eight Popular Peach Cultivars Produced in Shanghai Using GC-MS and GC-IMS

Peach (Prunus persica L.) is an economically important fruit crop worldwide due to its pleasant flavor. Volatile organic compounds (VOCs) are vital factors for assessing fruit quality. Here, we constructed the VOC profiles for the top eight popular commercial peach cultivars produced in Shanghai by combining gas chromatography-mass spectrometry (GC-MS), odor activity value and gas chromatograph-ion mobility spectrometry (GC-IMS). Seventy VOCs were detected using GC-MS, of which twenty-three were commonly found in eight peach cultivars, including hexanal, nonanal, benzaldehyde, 2-hexenal, butyl acetate, hexyl acetate, (Z)-3-hexen-1-yl acetate, linalool, β-myrcene, D-limonene, 1-hexanol, 3-hexenol, 2-hexenol, 2-ethyl-1-hexanol, γ-octalactone, δ-decalactone, γ-hexalactone, γ-decalactone, γ-dodecalactone, β-ionone, 2-octanone, 2-ethyl furan and 2,4-ditert-butyl phenol. A total of 17 VOCs were screened on the basis of OAV ≥ 1 and the top 5 of this contribution were γ-decalactone, β-ionone, hexanal, 2-hexenal and linalool. Lactones had the highest OAV in HJML and terpenoids had the highest OAV in JC. JXIU had the lowest OAV of lactones and terpenoids. Based on the range of their OAV values, the flavor evaluation standard of Shanghai high-quality peach cultivars can be established, which is also a reference for breeding excellent offspring. Twenty-six VOCs were detected using GC-IMS, and the largest proportion were aldehydes. Principal component analysis (PCA) showed that Hikawa Hakuho (HH) and Jinchun (JC) were distant from the other samples, indicating that their volatiles were more distinct. These results provide a foundation for improving our understanding of aroma compositions in these high-quality peach cultivars, which might also provide a reference for future design breeding to improve fruit flavor.

Geographic Differentiation of Essential Oil from Rhizome of Cultivated Atractylodes lancea by Using GC-MS and Chemical Pattern Recognition Analysis.

The rhizome of Atractylodes lancea (RAL) is a well-known Chinese herbal medicine (CHM) that has been applied in clinical settings for thousands of years. In the past two decades, cultivated RAL has gradually replaced wild RAL and become mainstream in clinical practice. The quality of CHM is significantly influenced by its geographical origin. To date, limited studies have compared the composition of cultivated RAL from different geographical origins. As essential oil is the primary active component of RAL, a strategy combining gas chromatography-mass spectrometry (GC-MS) and chemical pattern recognition was first applied to compare the essential oil of RAL (RALO) from different regions in China. Total ion chromatography (TIC) revealed that RALO from different origins had a similar composition; however, the relative content of the main compounds varied significantly. In addition, 26 samples obtained from various regions were divided into three categories by hierarchical cluster analysis (HCA) and principal component analysis (PCA). Combined with the geographical location and chemical composition analysis, the producing regions of RAL were classified into three areas. The main compounds of RALO vary depending on the production areas. Furthermore, a one-way analysis of variance (ANOVA) revealed that there were significant differences in six compounds, including modephene, caryophyllene, γ-elemene, atractylon, hinesol, and atractylodin, between the three areas. Hinesol, atractylon, and β-eudesmol were selected as the potential markers for distinguishing different areas by orthogonal partial least squares discriminant analysis (OPLS-DA). In conclusion, by combining GC-MS with chemical pattern recognition analysis, this research has identified the chemical variations across various producing areas and developed an effective method for geographic origin tracking of cultivated RAL based on essential oils.

AUTHENTICATION OF RATTUS NORVEGICUS FAT AND OTHER ANIMAL FATS USING GAS CHROMATOGRAPHY-MASS SPECTROMETRY (GC-MS) AND PRINCIPAL COMPONENT ANALYSIS (PCA)

Objective: The objective of this study was to analyze fatty acids using Gas Chromatography-Mass Spectrometry (GC-MS) in combination with chemometric Principal Component Analysis (PCA) for the authentication of Rattus norvegicus fat from other animal fats.
 Methods: Extraction of fat from raw meat of Rattus norvegicus, beef, chicken, pork, and dogs using the Bligh Dyer method, then derivatized with 0.2 N NaOCH3, precipitation of sodium glycerol was carried out by adding saturated NaCl to obtain methyl esters which were then injected into the GC-MS instrument. The GC-MS data were then processed using chemometric Principal Component Analysis (PCA) to group Rattus norvegicus fat with other animal fats (beef, chicken, pork, and dog).
 Results: The results of the study revealed that fatty acids in Rattus norvegicus using GC-MS produced eleven types of fatty acids, namely: Lauric acid (1,1%), Myristic acid (1,15%), Palmitic acid (21,12%), Palmitoleic acid (2,06%), Stearic acid (8,23%), Vaccenic acid (2,43%), Oleic acid (26,51%), Linoleic acid (19,19%), Arachidic acid (0,09%), and Eucosatrienoic acid (0,39%). Chemometrics Principal Component Analysis (PCA) of Rattus norvegicus fat allows it to be classified with other animal fats.
 Conclusion: The Gas Chromatography-Mass Spectrometry (GC-MS) method, in combination with chemometric Principal Component Analysis (PCA), offered effective tools for the authentication of fatty acid of Rattus norvegicus.

Composition of Strawberry Flower Volatiles and Their Effects on Behavior of Strawberry Pollinators, Bombus terrestris and Apis mellifera

Strawberries are popular fruits around the world, and their yield and fruit quality rely on pollination by honey bees and bumblebee colonies. Both bee species have their own advantages in strawberry pollination. This study investigates the characteristic of strawberry (Fragaria × ananassa ‘Red Face’) flower volatiles and their effects on bee pollinators by (1) detecting the volatile compounds of strawberry flowers by polydimethylsiloxane (PDMS) combined gas chromatography-mass spectrometry (GC-MS), (2) determining whether Bombus terrestris or Apis mellifera showed antennae responses to certain compounds of strawberry flower volatiles by an electroantennography test (EAG), and (3) testing whether these compounds could elicit a corresponding behavioral response in bees. The results showed that (1) there were 38 chemical compounds in ‘Red Face’ volatiles with 7 types, most of which were known to be generally emitted by flowers but also have some compounds that have not been reported in strawberry flowers; (2) B. terrestris and A. mellifera had strong EAG responses to several compounds, respectively, especially to ethyl benzoate, (Z)-3-hexenyl propionate, (Z)-3-hexenyl acetate, benzeneacetaldehyde and melonal; and (3) both bee species showed significant avoidance behaviors to four tested compounds, especially the B. terrestris. Flower volatiles of strawberry ‘Red face’ were different from other strawberry varieties that have been reported; some of these electrophysiologically active compounds could cause antennal potential responses in bees, as well as behavioral responses. Our study supports the idea that strawberry flower volatiles are one of the factors influencing bee foraging decisions and provides a reference for formulating more reasonable bee pollination to improve strawberry fruit quality.

Monitoring volatile changes in infant formula during long-term storage at room temperature

This study combined gas chromatography-mass spectrometry (GC-MS) and odor activity value (OAV) assessments to analyze the volatile ingredient changes in formula powder during 11 months of storage at room temperature. Orthogonal partial least squares-discriminant analysis (OPLS-DA) and variable importance in projection (VIP) were also used to assess the potential indicators of aroma changes during storage. The aim was to expose the possible changes in the aroma profile and the substances that alter infant formula (IF) aroma during storage. The results showed that the aldehyde and ketone content in the milk formula increased as the storage time was extended, while the lactone and terpenoid levels decreased significantly. The OAV indicated the presence of various major aromatic substances at different storage times. Considering consumer concern regarding product flavor, this study ascertained that monitoring substance changes during storage showed that 2-heptanone was a good indicator of milk flavor, dimethyl disulfide was a suitable indicator of protein degradation, and 3-methylbutanal, heptanal, hexanal, pentanal, and octanal were all good indicators of fat oxidation. The results of previous related studies were used to supplement the data in this work regarding the changes in IF during product shelf life and to provide support for controlling the flavor substances and quality during new product development.

Detection of Synthetic Cannabinoid CUMYL-PEGACLONE in E-Cigarette Oil and Hair.

To establish a combined high performance liquid chromatography-tandem mass spectrometry (HPLC-MS/MS) and gas chromatography-mass spectrometry (GC-MS) method to detect the synthetic cannabinoid CUMYL-PEGACLONE in e-cigarette oil and hair. HPLC-MS/MS and GC-MS were used to establish the detection method of CUMYL-PEGACLONE, and the hair of drug-involved persons and the seized e-cigarette oil were detected. The main mass spectrometry characteristic ions m/z of CUMYL-PEGACLONE measured by GC-MS were 91, 179, 197, 254 and 372. CUMYL-PEGACLONE had a good linear relationship in the mass concentration range of 2-50 ng/mL, and the linear correlation coefficient (r) was greater than 0.99. The limit of detection (LOD) of CUMYL-PEGACLONE in hair was 0.01 ng/mg, and the limit of quantitation (LOQ) was 0.02 ng/mg. The LOD of CUMYL-PEGACLONE in e-cigarette oil was 1 ng/mg, and the LOQ was 2 ng/mg. The average recoveries of CUMYL-PEGACLONE under the attempt at high, intermediate and low levels in blank human hair and e-cigarette oil matrix were 98.2%-132.4% and 93.5%-110.6%, and the intraday and intraday precision were 1.2%-12.9% and 0.7%-2.9%. CUMYL-PEGACLONE was detected in the hair of 15 drug-involved persons. Except for 1 person who was lower than LOQ, the concentration of CUMYL-PEGACLONE in the hair of other 14 persons was 0.035-0.563 ng/mg. The mass fraction of CUMYL-PEGACLONE in 2 e-cigarette oil were 0.17% and 0.21%, respectively. The established HPLC-MS/MS and GC-MS methods are applied to the detection of HPLC-MS/MS in drug-related cases, which provides strong evidence support for the handling authority to quickly investigate these cases, and also provides a reference for the identification of such substances in future.

HS-SPME-GC-MS and OAV analyses of characteristic volatile flavour compounds in salt-baked drumstick

Salt-baked drumstick of chicken is a traditional Cantonese food, but the flavour components remain vague. In this research, the volatile flavour compounds of salt-baked drumsticks were explored by headspace solid-phase microextraction (HS-SPME) combining gas chromatography-mass spectrometry (GC-MS). The result showed that 56 flavour compounds, 67flavour compounds and 62 flavour compounds were detected by the commercial water-baked drumsticks, the commercial salt-baked drumsticks and the self-manufactured salt-baked drumsticks, respectively. Then the combination of aroma threshold and odor activity value (OAV) theory further identified the flavour substances. Results showed that 19 volatile components were the main source of aroma, including aldehydes (9), alcohols (4), heterocycles (3), an ester compound, a phenolic compound and a hydrocarbon compound. There were 8 odorants with OAVs ≥10 in the drumsticks heating by salt, including octyl aldehyde, nonyl aldehyde, furfural, trans-2-nonenal, (E,E)-2,4-nonadienal, (E,E)-2,4-heptadienal, 1-octene-3-ol and ethyl cinnamate. This research identified major components of salt-baked drumstick during processing, which provided a foundation for further research on its formation mechanism and influence mechanism.

Comparison of Volatile Oil between the Ligusticum sinese Oliv. and Ligusticum jeholense Nakai et Kitag. Based on GC-MS and Chemical Pattern Recognition Analysis.

Ligustici Rhizoma et Radix (LReR) is the dried rhizomes and roots of Ligusticum sinese Oliv. (LS) or Ligusticum jeholense Nakai et Kitag. (LJ). However, in the market, LS and LJ are frequently confused with each other. Since the volatile oils are both the main active components and quality control indicators of LReR, a strategy combining gas chromatography-mass spectrometry (GC-MS) and chemical pattern recognition (CPR) was used to compare the volatile components of LJ and LS. Total ion chromatography (TIC) revealed that phthalides (i.e., neocnidilide) and phenylpropanoids (i.e., myristicin) could be thought of as the most critical components in the volatile oils of LJ and LS, respectively. In addition, the chemical components of the volatile oils in LJ and LS were successfully distinguished by hierarchical cluster analysis (HCA) and principal component analysis (PCA). Moreover, two quality markers, including myristicin and neocnidilide, with a very high discriminative value for the classification of LJ and LS, were found by orthogonal partial least squares discriminant analysis (OPLS-DA). The relative contents of myristicin and neocnidilide were 10.86 ± 6.18% and 26.43 ± 19.63% for LJ, and 47.43 ± 12.66% and 2.87 ± 2.31% for LS. In conclusion, this research has developed an effective approach to discriminating LJ and LS based on volatile oils by combining GC-MS with chemical pattern recognition analysis.

The chemical code for attracting Culex mosquitoes

Mosquitoes use chemical codes to locate and discriminate among vertebrate hosts to obtain a blood meal. Recent advances have allowed for the identification of the chemical codes used by mosquitoes to locate and discriminate humans from other vertebrate hosts. Humans are incidental “dead-end” hosts for the West Nile virus, which is maintained in an enzootic cycle, primarily through its transmission between infected birds by Culex mosquitoes. Host-seeking Culex mosquitoes are attracted to the odor of chicken, which are used in sentinel traps to monitor West Nile virus transmission. Using combined gas chromatography and electroantennography and mass spectrometry we identify a blend of volatile organic compounds present in chicken emanates, including mostly salient bioactive compounds previously identified in human emanates. When released at their identified ratios, this blend elicits behavioral responses of Culex pipiens molestus and Culex quinquefasciatus similar to that to the natural chicken odor. Tested under field conditions, this blend attract Culex spp. and other species of mosquitoes using birds among their hosts. This study provides evidence for conserved chemical codes for resource location by mosquitoes, and highlights the intricate role of CO2 for host-seeking mosquitoes. The identification of conserved chemical codes, which drive innate preference behaviors that are fundamental for survival and reproduction, provides important substrates for future control interventions targeting disease vector mosquitoes.

Network analysis combined with pharmacological evaluation strategy to reveal the mechanism of Tibetan medicine Wuwei Shexiang pills in treating rheumatoid arthritis

Tibetan medicine is an important part of traditional Chinese medicine and a significant representative of ethnic medicine in China. Tibetan medicine is gradually recognized by the world for its unique curative effects. Wuwei Shexiang pills (WPW) has been widely used to treat “Zhenbu” disease (Also known as rheumatoid arthritis) in Tibetan medicine, however, its potential bioactive ingredients and mechanism for RA treatment remain unclear. In this study, we used a combination of gas chromatography-mass spectrometry (GC-MS), ultra-performance liquid chromatography coupled with quadrupole time-of-fight mass spectrometry (UPLC-Q-TOF/MS), network analysis and experimental validation to elucidate the potential pharmacodynamic substances and mechanisms of WPW in the treatment of rheumatoid arthritis (RA). The results showed that songoramine, cheilanthifoline, saussureanine C, acoric acid, arjunolic acid, peraksine, ellagic acid, arjungenin and other 11 components may be the main activities of WPW in the treatment of RA. PIK3CA, AKT, MAPK, IL-6, TNF, MMP1, MMP3, and CDK1 are considered as core targets. PI3K-AKT, MAPK, apoptosis, cell cycle, and other signaling pathways may be the key pathways for WPW to play a role in the treatment of RA. Furthermore, we validated the underlying molecular mechanism of WPW predicted by network analysis and demonstrated its possible mechanism through in vivo animal experiments. It was found that WPW could significantly improve the degree of paw swelling, and reduce ankle joint diameter and arthritis index. Further histomorphological analysis showed that WPW could reduce the degree of synovial tissue inflammation and ankle joint cartilage damage. Meanwhile, WPW could down-regulate the levels of IL-6, IL-1β, and IL-17, and increase the levels of IL-10 and IL-4 in the serum of AA rats. TUNEL staining confirmed that WPW could significantly promote the apoptosis of synovial cells. Moreover, the immunohistochemical results showed that WPW decreased the expression of PI3K, AKT, MAPK, MMP1, MMP3, CDK1, and Bcl-2, as well as increased the expression of Bax protein. In conclusion, we successfully combined GC-MS, UPLC-Q-TOF/MS, network analysis, and experimental validation strategies to elucidate the inhibition of inflammation by WPW in AA model rats via PI3K/AKT, MAPK, cell cycle and apoptotic pathways process. This not only provides new evidence for the study of potential pharmacodynamic substances and the mechanism of WPW in the treatment of RA, but also provides ideas for the study of other Tibetan medicine compound preparations.

Integrated metabolomics revealed the fibromyalgia-alleviation effect of Mo2C nanozyme through regulated homeostasis of oxidative stress and energy metabolism

Fibromyalgia (FM), the most common cause of chronic musculoskeletal pain in the general public, lacks advanced therapeutic methodology and detailed bioinformation. However, acting as a newly developed and important transition metal carbide or carbonitride, the Mo2C nanozyme has provided a novel iatrotechnique with excellent bioactivity in a cell/animal model, which also exhibits potential prospects for future clinical applications. In addition, high-content and high-throughput integrated metabolomics (including aqueous metabolomics, lipidomics, and desorption electrospray ionization-mass spectrometry imaging) also specializes in qualitative and quantitative analysis of metabolic shifts at the molecular level. In this work, the FM-alleviation effect of Mo2C nanozyme was investigated through integrated metabolomics in a mouse model. An advanced platform combining gas chromatography-mass spectrometry, liquid chromatography-mass spectrometry and bioinformatics was utilized to study the variation in the mouse metabolome and lipidome. The results revealed that Mo2C treatment could effectively enhance energy metabolism-related biological events impaired by FM, leading to homeostasis of oxidative stress and energy metabolism toward the control levels. During this process, Mo2C facilitated the elimination of ROS in plasma and cells and the rehabilitation of mice from oxidative stress and mitochondrial dysfunction. It was believed that such an integrated metabolomics study on the FM-alleviation effect of Mo2C nanozyme could provide another excellent alternative to traditional Mo2C-based research with numerous pieces of bioinformation, further supporting research area innovation, material modification, and clinical application.

Untargeted metabolomics study of Lonicerae japonicae flos processed with different drying methods via GC-MS and UHPLC-HRMS in combination with chemometrics

The medicinal values and economic benefits of Lonicerae japonicae flos are directly affect by the post-harvest processing due to the organoleptic and chemical properties. To explore the differences of Lonicerae japonicae flos obtained by various drying methods, untargeted metabolomics combined with chemometrics was first used to investigate the metabolite differences among them. The metabolomics analysis was accomplished by introducing automatic data analysis tools, i.e., autoGCMSDataAnal and AntDAS, which developed for gas chromatography-mass spectrometry (GC-MS) data analysis and ultrahigh performance liquid chromatography-high resolution mass spectrometry (UHPLC-HRMS) data analysis, respectively. The results indicated that about 66 volatile compounds were screened and identified by autoGCMSDataAnal coupled with GC-MS, among which 29 compounds were confirmed qualitatively by standards. Meanwhile, 30 nonvolatile compounds were screened and identified by AntDAS combined with UHPLC-HRMS and 16 compounds were confirmed qualitatively by standards. In particular, most of polyphenols including rutin, cynaroside, isoquercetrin, chlorogenic acid etc., had their maximum content at the freeze drying and minimum at the shade drying. Finally, partial least squares discrimination analysis (PLS-DA), hierarchical clustering analysis (HCA) and heat map analysis were used for discriminating samples from various processing methods. Relative high-quality samples with good appearance characteristics could be obtained by freeze drying, heat-pump drying and hot air drying. Moreover, the antioxidant components were well preserved under freeze drying. The differences of primary and secondary metabolites in Lonicerae japonicae flos obtained with diverse drying methods were revealed, which could be helpful to determine the optimal drying method according to specific request.

A Bitter Pill

Residue was found in two cylindrical apothecary jars with similar inscriptions in the Rijksmuseum’s collection. There is a considerable difference in the age of these jars: the majolica albarello was made in Italy in the early sixteenth century, whereas the albarello made of tin-glazed earthenware was made in Delft more than two centuries later. Their inscriptions (JERA PIGRA and EL/ HIRAE PICRAE respectively) refer to the pharmaceutical preparation ‘hiera picra’ (Holy Bitter). The history of this medicine, which was said to give supernatural powers, goes back more than two thousand years. The main ingredient of this preparation was aloe Socotrina, which gave it its bitter taste. The research included the technique, shape, inscriptions, use and contents of these objects. Samples were taken from the residues found in both objects in order to determine the chemical composition. This was achieved using gas chromatographymass spectrometry (THM-GCMS) in combination with pyrolysis. A link to hiera picra could not be established, but the research provided a great deal of information about the background of both objects.

Metabolite profiling of Bruguiera cylindrica reveals presence of potential bioactive compounds

Bruguiera cylindrica parts are commonly used in Chinese and Indian traditional medicine to treat diarrhea, fever, and many ailments. The present study aims non targeted analysis of key secondary metabolites of B. cylindrica by gas chromatography mass spectrometry (GC-MS) and ultra-high performance liquid chromatography hybrid quadrupole-Exactive-Orbitrap high resolution mass spectrometry (UHPLC-Q-Exactive Orbitrap HRMS). GC-MS and UHPLC-Q-Exactive Orbitrap HRMS were utilized for metabolic profiling of ethyl acetate extract of B. cylindrica leaves. Key metabolites in the extract were identified and predicted based on chemical similarity using online databases such as ChemSpider and mzCloud. Thirty-six compounds belonging to different classes of secondary metabolites viz. flavonoids, fatty acids, fatty acid amides, carboxylic acids, and alkaloids were identified in the extract. Pentacyclic triterpenes like betulin, ursolic acid and a tropine, an alkaloid with potential pharmacological and therapeutic activities such as anticancer properties, neuromuscular blockers and antioxidants, were also identified. This study combined GC-MS and UHPLC-Q-Exactive Orbitrap HRMS with available online database for effective and rapid identification of bioactive metabolites in the ethyl acetate extract of mangrove without individual standard application. This is the first report on the HRMS based secondary metabolic profiling of B. cylindrica, with comprehensive map of its biologically important metabolites.