Fig 1 - uploaded by Abdul-Hamid Emwas
Content may be subject to copyright.
Source publication
Gas chromatography-mass spectrometry (GC-MS) has been widely used in metabonomics analyses of biofluid samples. Biofluids provide a wealth of information about the metabolism of the whole body and from multiple regions of the body that can be used to study general health status and organ function. Blood serum and blood plasma, for example, can prov...
Contexts in source publication
Context 1
... in a number of areas of research [53][54][55][56][57]. In addition to its high sensitivity, MS can be combined with other powerful analytical tools, such as gas chromatography (GC) or liquid chromatography (LC), so MS brings further advantages for the efficient separation of metabolites. The main components of a GC-MS instrument are shown in Fig. 1: an ionization chamber, mass analyzer, and detector maintained under a high vacuum. The function of the ionization section is to generate multiple ions from the samples under investi- gation, then the mass analyzer separates the ions on the basis of their mass-to-charge ratio (m/z), and the detector determines the m/z values and ...
Context 2
... the optimization of metabolite extrac- tion and sample deproteinization are very important steps in any metabonomics analyses. Figure 1 shows the main components of a GC-MS instrument where the sample first goes through the gas chromatography unit for the separation of compounds in a mixture. Then the molecules pass through the MS unit where they are ionized using an ionization method such as electron ionization. ...
Context 3
... GC-MS instrument, Fig. 1, consists of different parts to intro- duce, separate, and detect the analytes of interest. A heated control sample inlet (injector) is used to vaporize, homogenize, and concen- trate analytes in a sample mixture, a separation column encased in an oven to control the column temperature, and a ...
Context 4
... The stationary phase may have either a solid- phase gas–solid chromatography (GSC) or a polymeric liquid-phase gas–liquid chromatography (GLC), in which the stationary phase is coated onto the inner wall of a capillary column. In gas chromatography, analytes of interest in a mixture of compounds are contained in an inert carrier gas. Depending on their vapor pressures, the analytes are vaporized and pumped through a stationary phase. The chemical and physical natures of analytes cause them to interact differently with the stationary phase and therefore elute form the column at different retention times. The attraction between an analyte and the stationary phase is governed by the distribution of the compound between the stationary phase and the gas mobile phase (partitioning), which is expressed by the distribution coeffi cient K (Eq. 1 ): ( 1 ) where: C s is the concentration of analyte in the stationary phase. C m is the concentration of analyte in the gas phase. A larger K c value leads to a longer retention time of a compound in the stationary phase and inside the column. The distribution _ coeffi cient is controlled by the temperature of the column and the chemical properties of the stationary phase. The degree and the rate of partitioning of a chemical compound between the stationary phase and gas phase are infl uenced by the affi nity of the compound for the stationary phase and the analyte vapor pressure which is controlled by the column temperature. A GC–MS instrument, Fig. 1 , consists of different parts to introduce, separate, and detect the analytes of interest. A heated control sample inlet (injector) is used to vaporize, homogenize, and concen- trate analytes in a sample mixture, a separation column encased in an oven to control the column temperature, and a detector. The GC sample inlet is the part of the GC system, which is used to transfer the complex mixture onto the analytical column. The inlet could be a vaporization inlet within which heat is applied in order to vaporize the sample and introduce it onto the column. Such inlets include split/splitless and programmed temperature vapor- izers (PTV). Alternatively, a non-vaporized inlet such as cool-on- column (COC) inlet may be used whereby a liquid sample is transferred directly onto the column without vaporization. The inlet is designed as a combination inlet for both split and splitless injections. In split mode the inlet vent most of the vaporized sample but transfer most of it when splitless mode is applied. The split mode is used when the concentration of an analyte in the sample matrix is high enough to be detected, whereas the splitless injection mode is used for trace ...
Context 5
... cation [ 26 – 35 ], for solid-state [ 36 – 38 ] and tissue samples [ 39 – 43 ], as well as for solution samples [ 44 – 48 ]. However, despite recent developments of NMR machinery such as the introduction of dynamic nuclear polarization (DNP) [ 49 – 52 ], low sensitivity remains the intrinsic restriction of NMR spectroscopy, and secondary metabolites, for example, are still beyond the detection limit of NMR spectroscopy. Consequently, MS is the method of choice for the detection of molecules present in low concentrations and provides a powerful analytical platform for metabonomics applications in a number of areas of research [ 53 – 57 ]. In addition to its high sensitivity, MS can be combined with other powerful analytical tools, such as gas chromatography (GC) or liquid chromatography (LC), so MS brings further advantages for the effi cient separation of metabolites. The main components of a GC–MS instrument are shown in Fig. 1 : an ionization chamber, mass analyzer, and detector maintained under a high vacuum. The function of the ionization section is to generate multiple ions from the samples under investigation, then the mass analyzer separates the ions on the basis of their mass-to-charge ratio ( m / z ), and the detector determines the m / z values and records the relative abundance of each type of ion. The fact that the identifi cation of detected compounds is based on both a mass spectrum and a retention time underpins one of the most prominent advantages of GC–MS, whereby a combination of both properties is used for identifi cation. In addition to its application for the identifi cation of metabolites, GC–MS can also be employed for the quantitative analysis of analytes using appropriate standards. Due to enormous complexity and dynamics of biological samples such as human blood, comprehensive profi ling of the metabolome is a challenging task. GC–MS-based metabonomics has used a range of different methods for the metabolic profi ling of different chemical classes, such as organic acids, carbohydrates, amines, and amino acids [ 58 – 66 ...
Context 6
... has reviewed the different problems associated with artifacts and has proposed means for avoiding formation of artifacts [ 96 ]. Agents N -methyl- N -(tert-butyldimethylsilyl) trifl uoroacetamide (MTBDMSTFA) and tert -butyldimethylchlorosilane (TBDMCS) are also used for derivatization (Fig. 2 ), both will replace active hydrogen in –COOH, –OH, –NH, and –SH groups with tert butyldimethylsilyl group ( tert -DMSC). The tert -BDMS derivatives were found to be stable with 2 % residual water in the samples [ 97 ]. Tert-butyldimethylsilylation (tert-BDMS) is also used for derivatization, and tert-BDMS derivatives have been found to be stable with 2 % residual water in the samples [ 97 ]. Moreover, the spectra of tert-BDMS derivatives displayed a characteristic frag- mentation, a fragment ion of [M-57] being associated with the loss of a tert-butyl group, which can be helpful for the identifi cation of unknown metabolites [ 98 ]. In order to maximize the number of metabolites that can be detected by GC–MS, a two-step derivatization procedure is usually recommended, which includes methoximation (Scheme 2 ) followed by silylation, this is often being used for metabolic fi ngerprinting [ 99 – 101 ]. For comparative results and to avoid false conclusions, any GC–MS-based metabonomics analysis should be carried out under well-controlled conditions using standard operating procedures (SOPs). These must include protocols for collecting the samples, the transportation, and storage conditions, as well as all steps of sample preparation. Blood serum and plasma contain a wide range of different classes of metabolite, which are also varied in concentration and level of stability and may also be non-covalently bound to protein. Consequently, the optimization of metabolite extraction and sample deproteinization are very important steps in any metabonomics analyses. Figure 1 shows the main components of a GC–MS instrument where the sample fi rst goes through the gas chromatography unit for the separation of compounds in a mixture. Then the molecules pass through the MS unit where they are ionized using an ionization method such as electron ionization. Next, the molecules and/or molecule fragments are detected based on their mass-to-charge ratios. The gas chromatography consists of a gas supply for the mobile phase (commonly used carrier gases are N 2 , H 2 , or He), fl ow controls for carrier gas control, a heat-controlled injector, a heat control oven for heating the column, a detector, and a data- ...
Similar publications
In vitro high-throughput non-depletive quantitation of chemicals in biofluids is of growing interest in many areas. Some of the challenges facing researchers include the limited volume of biofluids, rapid and high-throughput sampling requirements, and the lack of reliable methods. Coupled to the above, growing interest in the monitoring of kinetics...
Assessment of a tumor's molecular makeup using biofluid samples, known as liquid biopsy, is a prominent research topic in precision medicine for cancer, due to its noninvasive property allowing repeat sampling for monitoring molecular changes of tumors over time. Circulating exosomes recently have been recognized as promising tumor surrogates becau...
Biofluids, such as serum and plasma, represent an ideal medium for the diagnosis of disease due to their ease of collection, that can be performed worldwide, and their fundamental involvement in human function. The ability to diagnose disease rapidly with high sensitivity and specificity is essential to exploit advances in new treatments, in additi...
In this historical review the main topics of research in the Department of Biomedical Engineering of the Technomedicum of the Tallinn University of Technology are discussed.
Pseudomonas aeruginosa produces quorum sensing signal molecules that are potential biomarkers for infection. A prospective study of 60 cystic fibrosis patients with chronic P. aeruginosa, who required intravenous antibiotics for pulmonary exacerbations, was undertaken. Clinical measurements and biological samples were obtained at the start and end...
Citations
... Each method possesses unique strengths based on the specific metabolites under analysis. GC-MS is particularly effective for the examination of volatile compounds or those that may be rendered volatile through derivatization, making it suitable for volatile organic metabolites [30]. Conversely, LC-MS is better suited for the analysis of polar, thermally labile compounds that do not readily vaporize. ...
Background/Objectives: Although malaria is one of the oldest known human diseases, it continues to be a major global health challenge. According to UNICEF, the global malaria mortality rate exceeded 600,000 annually in 2022, which includes more than 1000 children dying each day. This study aimed to investigate the comprehensive chemical profile and biological activities, particularly the antimalarial activity, of Lycium shawii (Awsaj), a shrub traditionally used in the Arabian Peninsula, Middle East, India, and Africa to treat a myriad of ailments. Methods: Crude extracts of L. shawii were prepared using water, ethanol, methanol, and acetone. Nuclear magnetic resonance (NMR) spectroscopy and mass spectrometry (MS) were utilized to perform untargeted metabolomics to maximize metabolite detection and tentatively identify bioactive phytochemicals. The total phenolic content (TPC) was measured for each extract, and bioassays were conducted to evaluate their antimalarial, antibacterial, and anti-inflammatory activities, particularly those of the water extract, which is the traditional method of consumption in Arabian folk medicine. Results: A total of 148 metabolites were detected, 45 of which were classified as phytochemicals. The bioassays revealed that the water extract that is traditionally used showed promising antimalarial potential by significantly inhibiting β-hematin formation in vitro at 1 mg/mL (with an absorbance of 0.140 ± 0.027). This is likely due to the rich presence of quinoline in the aqueous extract among several other bioactive phytochemicals, such as phenylpropanoids, alkaloids, flavonoids, and benzenoids. However, their anti-inflammatory and antibacterial activities were found to be weak, with only a minor inhibition of nitric oxide (NO) production in LPS-induced RAW 264.7 cells at a concentration of 500 µg/mL and weak antibacterial effects against pathogens like P. aeruginosa, MRSA, A. baumannii, and K. pneumoniae with an MIC of 500 μg/mL. The results also revealed that the methanolic extract had the highest TPC at 26.265 ± 0.005 mg GAE/g. Conclusions: The findings support the traditional medicinal use of L. shawii and highlight its potential as a source of novel therapeutic compounds, particularly for treating malaria. This study encourages further research to isolate and develop effective plant-based anti-malarial agents.
... A schematic diagram of GC-MS illustrating key components for analysis (Emwas et al., 2015). ...
Vanilla (Vanilla planifolia) is the world's most preferred aroma and
flavoring agent. Therefore, its market value in the food, beverages,
baking, cosmetics, and pharmaceutical industries is constantly growing.
The compounds found in vanilla, chiefly influenced by the vanillin
component, contribute to this orchid's aromatic and flavoring properties.
Vanillin content has improved in cured and fermented vanilla bean pods.
Hence, curing vanilla has been revealed in research, and vanillin,
phenolic and/or aromatic components, and organic acids develop
significantly when green matured beans are allowed to ferment naturally.
However, curing vanilla beans can be tiresome and costly due to the
constant observation of the vanilla beans in storage and conditioning
facilities. The loss of samples contaminated with molds, the breakup of
pods, and natural enemies such as pests and diseases are other challenges
that processors face. Therefore, at post-harvest, the curing of vanilla
beans is a crucial management of the pods wherein farmers could lose
their yields. The curing process involves blanching or killing harvested
vanilla pods, followed by the sweating stage, where pods are fermented
traditionally or with innovative strategies. The fermented vanilla pods
are then transferred to the conditioning and slow-drying stages, wherein
a dark brown and shiny with elevated odor is obtained. Notably, the
aroma and flavor of vanilla beans increase during this process, while
edible bacteria could also assist in the fermentation or sweating stage.
Notably, very few studies have been reported about edible bacteria
isolations from V. planifolia and their fermentation roles during the
curing process while indirectly influencing the aromatic properties of the
orchid. This research used a fermentation technique by coating isolated
pure bacteria from previously traditionally fermented vanilla on green-
harvested pods from Taiwan. Hence, we hypothesized that bacterial
fermentation in V. planifolia may increase the microbial communities,
influencing the pods' volatile characteristics (such as aroma and flavor).
The vanilla pods were then coated with B. velezensis ZN-S10 during
the sweating or fermentation and then subjected to next-generation
sequencing (NGS). Firmicutes were the most dominant phyla in the
bacteria communities of B. velezensis ZN-S10 coated vanilla during the
fermentation stage of the curing process. The NGS findings showed that
the microbial diversity in alpha (α) and beta (β) analysis, evenness, and
richness were higher in ZN-S10 bacterial fermentation compared to the
control samples. The circos plot analysis further confirmed that the
Bacilli class and Bacillales order were the most dominant within the
microbiota of ZN-S10 treatment. This showed that edible Bacillus
isolates could increase the microbial diversity of V. planifolia beans,
which could also improve their volatile properties.
The specific compounds detected by GC-MS also provided a better
understanding of the particular compounds and their relationship with
the sensory attributes of V. planifolia and their potential implications for
flavor development. This was proven by the increased number of
compounds detected in the methanol extracts of bacteria-treated vanilla
compared to the non-treated vanilla pods. B. velezensis ZN-S10
exhibited 7 volatile compounds, and B. tropicus KhEp-2 contained 6
compounds, whereas the control samples showed only 3, indicating
enhanced aromatic and flavor qualities with these strains. The quality
compound p-hydroxybenzaldehyde was present only in B. tropicus
KhEp-2 vanilla coating. Also, the compound 3-deoxy-d-mannoic
lactone was found in the methanol extracts of vanilla pods fermented
with B. vallismortis NR
_
104873.1:11-1518, which has not been reported
in other vanilla studies. The compound has been found to contribute to
the smoky, fruity, and creamy aroma of other fermented fruits. Thus, the
results exhibit an emerging biotechnological technique of improving the
vanilla profile at post-harvest for better quality products using edible
bacteria such as Bacillus strains. Therefore, the post-harvest
management of vanilla beans in low-temperature treatment under well-
monitored curing conditions could be used in vanilla processing to yield
high-quality vanilla bean pods.
... 53 Lipidomics has been studied using an array of chromatography and mass spectrometry techniques, such as gas chromatography-mass spectrometry (GC-MS), gas chromatography-tandem mass spectrometry (GC-MS/MS), liquid chromatography-mass spectrometry (LC-MS), and liquid chromatography-tandem mass spectrometry (LC-MS/MS). [54][55][56][57][58] However, the use of GC involves multiple manipulation and derivatization steps, potentially leading to lipid oxidation 59 and undesired isomerization processes. 60 NMR-based metabolomics is widely used in various elds, including nutrition research, 61 and in the realm of food-omics, NMR-based approaches have proven successful in exploring variations in metabolite proles. ...
Lipids play crucial roles in human biology, serving as energy stores, cell membranes, hormone production, and signaling molecules. Accordingly, their study under lipidomics has advanced the study of living organisms. 1-Dimensional (D) and 2D NMR methods, particularly 1D ¹H and 2D ¹H–¹H Total Correlation Spectroscopy (TOCSY), are commonly used in lipidomics for quantification and structural identification. However, these NMR methods suffer from low sensitivity, especially in cases of low concentrated molecules such as protons attached to hydroxy, esters, aliphatic, or aromatic unsaturated carbons. Such molecules are common in complex mixtures such as dairy products and plant oils. On the other hand, lipids have highly populated fractions of methyl and methylene groups that result in intense peaks that overwhelm lower peaks and cause inhomogeneities in 2D TOCSY spectra. In this study, we applied a method of suppression to suppress these intense peaks of methyl and methylene groups to detect weaker peaks. The suppression method was investigated on samples of cheese, butter, a mixture of lipids, coconut oil, and olive oil. A significant improvement in peak sensitivity and visibility of cross-peaks was observed, leading to enhanced comparative quantification and structural identification of a greater number of lipids. Additionally, the enhanced sensitivity reduced the time required for the qualitative and comparative quantification of other lipid compounds and components. This, in turn, enables faster and more reliable structural identification and comparative quantification of a greater number of lipids. Additionally, it reduces the time required for the qualitative, and comparative quantification due to the enhancement of sensitivity.
... GC-MS faces a limitation wherein the analyst metabolites must be volatile and thermally stable [8] . This poses a challenge as many metabolites, especially polar compounds, do not meet these criteria. ...
... This poses a challenge as many metabolites, especially polar compounds, do not meet these criteria. To overcome this, derivatization agents, such as trimethylsilyl (TMS) groups, are commonly employed to enhance volatility and thermal stability and reduce polarity [8] . A derivatization solution was prepared by mixing 10 μL of hydrocarbon mixture (C7-C40) with 1 mL of BSTFA [N, O-Bis(trimethylsilyl)trifluoroacetamide]. ...
Metabolomics, a recent addition to omics sciences, studies small molecules across plants, animals, humans, and marine organisms. Nuclear magnetic resonance (NMR) and gas chromatography-mass spectrometry (GC–MS) are widely used in those studies, including microalgae metabolomics. NMR is non-destructive and highly reproducible but has limited sensitivity, which could be supplemented by joining GC–MS analysis. Extracting metabolites from macromolecules requires optimization for trustworthy results. Different extraction methods yield distinct profiles, emphasizing the need for optimization. The results indicated that the optimized extraction procedure successfully identified NMR and GC–MS-based metabolites in MeOH, CHCl3, and H2O extraction solvents. The findings represented the spectral information related to carbohydrates, organic molecules, and amino acids from the water-soluble metabolites fraction and a series of fatty acid chains, lipids, and sterols from the lipid fraction. Our study underscores the benefit of combining NMR and GC–MS techniques to comprehensively understand microalgae metabolomes, including high and low metabolite concentrations and abundances.•In this study, we focused on optimizing the extraction procedure and combining NMR and GC–MS techniques to overcome the low NMR sensitivity and the different detected range limits of NMR and GC–MS.
•We explored metabolome diversity in a tropical strain of the small cells’ diatom Cheatoceros tenuissimus.
... Gaz kromatografi kütle spektrometri tekniği şeması(14) ...
Toksikolojik analizler toksik ve yasadışı maddelerin tespiti, ilişkili olduğu hastalıkların tanı, takip ve tedavisinin değerlendirilmesi için yapılır. Numune türü olarak idrar, serum, plazma, kan, saç, tükürük, ter, tırnak, mide aspiratı ve içerisinde yabancı bir maddenin arandığı her türlü katı veya sıvı kullanılır. Bu analizlerdeki tarama yöntemleri hızlı, ucuz, yüksek hassasiyetli ve düşük özgüllüklü iken, doğrulama yöntemleri yavaş, pahalı, yüksek hassasiyet ve özgüllüklüdür. Tarama yöntemleri başlıca immunoassayler ve kromatografik teknikler olup negatif örnekleri pozitif örneklerden ayırmak için, doğrulama yöntemleri ise tarama testlerinde pozitif çıkan sonuçların doğrulanması için kullanılır. Altın standart doğrulama yöntemi kütle spektrometridir. Immunoassayler özgül olmadığı için çapraz reaksiyonlar görülebilir. Yüksek basınçlı sıvı kromatografi polar ve uçucu olmayan örnekler için uygun iken, gaz kromatografi uçucu örnekler için uygundur. Gaz kromatografi kütle spektrometri yöntemi immunoassay ve yüksek basınçlı sıvı kromatografi tekniğinden daha sensitif iken örnek hazırlama süresi daha uzundur. Çünkü separasyon için maddeler ve metabolitleri genellikle az polar ve daha uçucu türevlerine dönüştürülür. Sıvı kromatografi sıralı kütle spektrometri tekniğinin ise özgüllüğü ve duyarlılığı yüksektir, ancak analizi komplekstir, deneyimli personel gerekir ve maliyeti yüksektir. Toksikolojik analizler için yeterli olabilen tek bir analitik teknik yoktur. Birden fazla tekniğin kombine edilmesi önerilir.
... The GC-MS possesses the capability to efficiently separate heterogeneous compounds and the detection of the separated molecules. 9 In the GC-MS, the mass analyser separates the ions in the heterogeneous compound based on their respective mass to charge ratio, while the detector determines the mass to charge values and records the relative abundance. ...
... With the detection of individual compounds through the production of mass spectrum and retention time parameters, the GC-MS is advantageous and mostly employed in the quantitative determination of heterogeneous biological compounds. 9,10 Fourier transform-Infrared spectroscopy (FT-IR) technique identifies substances through the extent of absorption of mid-infrared (IR) radiation, the interaction with electromagnetic fields in the IR region and their characteristic molecular vibrations. 11,12 With the exposure of matter to IR, absorption of IR cause molecules to vibrate, The extent of vibration provides compositional information of the matter. ...
... Phytochemicals were determined through the comparison of mass spectra generated from analyte and reference sample. 9,10 The concentration of the different phytochemicals is expressed in µg/g, µg/mL or ppm. Identified compounds were matched with the National Institute Standard and Technology (NIST) database. ...
Annona muricata Linn (A. muricata) belongs to the Annonaceae family, it is well-known for its high nutritional index and therapeutic relevance in traditional medicine. Aim of the study: To determine and compare the bio-active compounds profiled from selected parts of the A. muricata plant. In addition, study findings is aimed at advancing pharmacological knowledge of selected plant parts of A. muricata. Gas chromatography-Mass spectrometry (GC-MS) and Fourier transform-infrared (FT-IR) spectroscopy were utilised to comparatively profile the phytochemical compositions of the ethanolic extracts of A. muricata seeds and leaves. From GC-MS analyses, nineteen phytochemical compounds were identified in the ethanolic extract of A. muricata seeds while eighteen phytochemical compounds were identified in the ethanolic extract of A. muricata leaves. Comparatively, cyanogenic glycosides, resveratrol and tannin were identified uniquely from A. muricata seeds, while the cardiac glycosides and anthocyanin were identified uniquely from A. muricata leaves. The FT-IR analyses confirmed the presence of C-Cl, C-O, C=C, N-H, SCN and -OH functional groups. However R2CHOH and R-COO were identified uniquely in A. muricata seeds and leaves respectively. These findings will be relevant in plant pharmacology and the development of enhanced medical strategies.
... Several analytical technologies have proven effective in the quantification of metabolites, such as liquid chromatography coupled with tandem mass spectrometry (LC-MS/MS) (Huang et al. 2013) or single-stage mass spectrometry (LC-MS) (Liu et al. 2014), high or ultra-high performance liquid chromatography paired with fluorescent or UV detection (HPLC/UPLC) (Molz et al. 2014), gas chromatography integrated with mass spectrometry (Emwas et al. 2015), and nuclear magnetic resonance (NMR) spectroscopy (Kim et al. 2013). Every analytical platform has its pros and cons. ...
... Analytical chemistry is constantly evolving and taking advantage of new developments in analytical techniques, instrumentation, analytical software, statistical methods, or computational techniques to accelerate or improve data collection, analysis, and interpretation. The primary analytical technologies used in metabolomics include liquid chromatography coupled with single-stage mass spectrometry (LC-MS) [10][11][12] or tandem mass spectrometry (LC-MS/MS) [13][14][15][16][17][18], gas chromatography coupled to mass spectrometry (GC-MS) [10,11,19,20], high-or ultrahigh-performance liquid chromatography coupled to UV or fluorescent detection (HPLC/UPLC) [21][22][23][24][25][26][27][28], and nuclear magnetic resonance (NMR) spectroscopy [29][30][31][32][33][34][35][36]. Each analytical platform has its advantages and disadvantages. ...
The metabolomics and proteomics analysis of saliva, an excellent biofluid that is a rich source of biological compounds, allows for the safe and frequent screening of drugs, their metabolites, and molecular biomarkers of various diseases. One of the most frequently used analytical methods in saliva analysis is liquid chromatography coupled with mass spectrometry (LC-MS) and tandem mass spectrometry. The low ionisation efficiency of some compounds and a complex matrix makes their identification by MS difficult. Furthermore, quantitative analysis by LC-MS frequently cannot be performed without isotopically labelled standards, which usually have to be specially synthesised. This review presented reports on qualitative and quantitative approaches in salivary metabolomics and proteomics. The purpose of this manuscript was to present the challenges, advances, and future prospects of mass spectrometry, both in the analysis of salivary metabolites and proteins. The presented review should appeal to those interested in the recent advances and trends in qualitative and quantitative mass spectrometry in salivary metabolomics and proteomics, which may facilitate a diagnostic accuracy, the evaluation of treatment efficacy, the early diagnosis of disease, and a forensic investigation of some unapproved drugs for any medical or dietary administration.
... Metabolomics, similarly to other "-omics" disciplines, is a technology-driven field, where different analytical tools are applied, including nuclear magnetic resonance (NMR) (26,27), Fourier-transform infrared spectroscopy (FT-IR) (28)(29)(30)(31)(32)(33)(34), high-performance liquid chromatography (HPLC) (35) and mass spectrometry (MS) (36,37). NMR spectroscopy and MS spectrometry, which is usually combined with liquid chromatography (38) or gas chromatography (37,(39)(40)(41), are the most frequently used platforms in metabolomic studies (27,42,43). ...
... Metabolomics, similarly to other "-omics" disciplines, is a technology-driven field, where different analytical tools are applied, including nuclear magnetic resonance (NMR) (26,27), Fourier-transform infrared spectroscopy (FT-IR) (28)(29)(30)(31)(32)(33)(34), high-performance liquid chromatography (HPLC) (35) and mass spectrometry (MS) (36,37). NMR spectroscopy and MS spectrometry, which is usually combined with liquid chromatography (38) or gas chromatography (37,(39)(40)(41), are the most frequently used platforms in metabolomic studies (27,42,43). ...
Over the course of years healthcare systems have utilized various '-omics' approaches to prognose, diagnose and evaluate the treatment efficacy of cancer diseases. Metabolomics is one of the latest prominent additions to the-omics approaches, characterized by its versatile methodology. Owing to constant improvements in the field, a metabolomic aims to provide a faster and a more accurate diagnosis, as well as personalized and optimal strategies of treatment. In recent years, a growing number of studies have utilized metabolomics approach to find new disease-related biomarkers of cancer diseases. Here we present the summary of recent advances in biomarker discovery for various types of cancers such as leukemia, ovarian, lung, breast and liver cancers as well as cancer-related cachexia.
... Các mẫu tinh dầu được đo tại Phòng thí nghiệm hoá phân tích, Trường Đại học Bách khoa Hà Nội. [13]. ...
... Sản phẩm đáy thu được chứa hàm lượng cấu tử anethole là 88,08 wt.%, ngoài ra các có cấu tử như limonene 0,21 wt.%, terpinen-4-ol 0,09 wt.%, methyl chavicol 2,69 wt.%, anisaldehyde 2,87 wt.%, caryophyllene 1,42 wt.%, β-bergamoten 1,55 wt.%, 1-(3-methyl-2-butenoxy)-4-(1propenyl) benzene 1,61 wt.%, và 1,48 wt.% các chất khác. Tạp chất thu được ở đỉnh tháp cho thấy các cấu tử có nhiệt độ sôi thấp và trung bình như limonene (18,57 wt.%), linalool (30,50 wt.%) và methyl chavicol (13,71 wt.%) được tách ra với hàm lượng tương đối lớn. Kết quả này cho thấy trong sản phẩm đáy hầu như không còn hiện diện của cấu tử có nhiệt độ sôi thấp như limonene, α-pinene, β-phellandrene; các chất có nhiệt độ sôi trung bình như linalool, methyl chavicol, terpinen-4-ol có hàm lượng tương đối thấp. ...
Vietnam is one of the world’s largest annual anise harvest countries. However, products from anise are mainly in the form of dried anise fruit and crude star anise essential oil with low economic value. The main component of the star anise essential oil is trans-anethole which needs to be purified to produce higher-value products. This study focused on building an experimental system for purifying star anise essential oil by a batch distillation column working at vacuum pressure. The products obtained during the purification process were analysed by gas chromatography-mass spectrometry (GC-MS). Analytical results were used to evaluate the ability to separate volatile impurities in the crude star anise essential oil. Results showed that the bottom temperature of the tower below 150oC, corresponding to a vacuum pressure of less than 0.1 bar, can reduce the thermal decomposition of essential oils. The volatile components, such as α-pinene, β-phellandrene, limonene, and linalool, were thoroughly separated at the top of the tower. The purified star anise essential oil was from the bottom of the distillation and had the anethole composition of over 88% of mass fraction (wt.%). Anethole recovery efficiency was 98.5 and 88.8% at a pressure of 0.1 and 0.08 bar, respectively. The bottom product can have a higher anethole composition if increasing the column height, the reflux ratio, and decreasing the pressure and the quality of impurities removed at the top is increased.The experimental results are helpful for the calculation, design, manufacture, and operation of an industrial-scale essential oil purification system.
