The impact of mass spectrometry application to screen new proteomics biomarkers in Ophthalmology

Plant polyphenols have beneficial antioxidant effects on human health; practices aimed at preserving their content in foods and/or reusing food by-products are encouraged. The impact of the traditional practice of the water curing procedure of chestnuts, which prevents insect/mould damage during storage, was studied to assess the release of polyphenols from the fruit. Metabolites extracted from pericarp and integument tissues or released in the medium from the water curing process were analyzed by matrix-assisted laser desorption ionization-time of flight-mass spectrometry (MALDI-TOF-MS) and electrospray-quadrupole-time of flight-mass spectrometry (ESI-qTOF-MS). This identified: (i) condensed and hydrolyzable tannins made of (epi)catechin (procyanidins) and acid ellagic units in pericarp tissues; (ii) polyphenols made of gallocatechin and catechin units condensed with gallate (prodelphinidins) in integument counterparts; (iii) metabolites resembling those reported above in the wastewater from the chestnut curing process. Comparative experiments were also performed on aqueous media recovered from fruits treated with processes involving: (i) tap water; (ii) tap water containing an antifungal Lb. pentosus strain; (iii) wastewater from a previous curing treatment. These analyses indicated that the former treatment determines a 6–7-fold higher release of polyphenols in the curing water with respect to the other ones. This event has a negative impact on the luster of treated fruits but qualifies the corresponding wastes as a source of antioxidants. Such a phenomenon does not occur in wastewater from the other curing processes, where the release of polyphenols was reduced, thus preserving the chestnut’s appearance. Polyphenol profiling measurements demonstrated that bacterial presence in water hampered the release of pericarp metabolites. This study provides a rationale to traditional processing practices on fruit appearance and qualifies the corresponding wastes as a source of bioactive compounds for other nutraceutical applications.

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Quantitative Analysis of Pyrazines and Their Perceptual Interactions in Soy Sauce Aroma Type Baijiu

Foods ◽

10.3390/foods10020441 ◽

2021 ◽

Vol 10 (2) ◽

pp. 441

Author(s):

Yan Yan ◽

Shuang Chen ◽

Yao Nie ◽

Yan Xu

Keyword(s):

Mass Spectrometry ◽

Quantitative Analysis ◽

Ultra Performance Liquid Chromatography ◽

Alcohol Solution ◽

Soy Sauce ◽

Tandem Mass ◽

Odor Thresholds ◽

Quantitative Results ◽

Odor Activity Value ◽

The Impact

Pyrazines are important compounds in soy sauce aroma type Baijiu (SSAB). In this work, a total of 16 pyrazines were analyzed using ultra-performance liquid chromatography coupled with tandem mass spectrometry (UPLC–MS/MS) in SSAB. The quantitative results showed that 2,3,5,6-tetramethylpyrazine, 2,6-dimethylpyrazine and 2,3,5-trimethylpyrazine were the three most concentrated pyrazines. The highest odor activity value (OAV) was determined for 2-ethyl-3,5-dimethylpyrazine. Quantitative analysis combined with descriptive sensory analysis revealed that sub-threshold pyrazines (2,3-dimethylpyrazine, 2,3-diethylpyrazine, 2,3-diethyl-5-methylpyrazine and 2-acetyl-3-methylpyrazine) are significantly correlated with the roasted aroma in SSAB. Our study focused on the impact of sub-threshold pyrazines on the perception of roasted aroma in SSAB. The effect of the sub-threshold pyrazines was detected by the addition of various pyrazines in SSAB samples, despite their sub-threshold concentrations. Furthermore, the presence of sub-threshold pyrazines in dilute alcohol solution resulted in a significant reduction in the odor thresholds of supra-threshold pyrazines. Sensory investigation indicated that pyrazines have a synergistic effect on the perception of roasted aroma. The results highlighted the contribution of some pyrazines to the roasted aroma in SSAB despite their sub-threshold concentrations.

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Matrix-assisted laser desorption ionisation (MALDI) mass spectrometry (MS): basics and clinical applications

Clinical Chemistry and Laboratory Medicine (CCLM) ◽

10.1515/cclm-2019-0868 ◽

2020 ◽

Vol 58 (6) ◽

pp. 883-896 ◽

Cited By ~ 3

Author(s):

Muhammad Zubair Israr ◽

Dennis Bernieh ◽

Andrea Salzano ◽

Shabana Cassambai ◽

Yoshiyuki Yazaki ◽

...

Keyword(s):

Mass Spectrometry ◽

Laser Desorption ◽

Maldi Mass Spectrometry ◽

Clinical Applications ◽

Clinical Diagnostics ◽

Maldi Ms ◽

Therapeutic Drug ◽

The Impact ◽

Matrix Assisted Laser ◽

Matrix Assisted Laser Desorption

AbstractBackgroundMatrix-assisted laser desorption ionisation (MALDI) mass spectrometry (MS) has been used for more than 30 years. Compared with other analytical techniques, it offers ease of use, high throughput, robustness, cost-effectiveness, rapid analysis and sensitivity. As advantages, current clinical techniques (e.g. immunoassays) are unable to directly measure the biomarker; rather, they measure secondary signals. MALDI-MS has been extensively researched for clinical applications, and it is set for a breakthrough as a routine tool for clinical diagnostics.ContentThis review reports on the principles of MALDI-MS and discusses current clinical applications and the future clinical prospects for MALDI-MS. Furthermore, the review assesses the limitations currently experienced in clinical assays, the advantages and the impact of MALDI-MS to transform clinical laboratories.SummaryMALDI-MS is widely used in clinical microbiology for the screening of microbial isolates; however, there is scope to apply MALDI-MS in the diagnosis, prognosis, therapeutic drug monitoring and biopsy imaging in many diseases.OutlookThere is considerable potential for MALDI-MS in clinic as a tool for screening, profiling and imaging because of its high sensitivity and specificity over alternative techniques.

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Determination of multi pesticide residues in leaf and needle samples using a modified QuEChERS approach and gas chromatography-tandem mass spectrometry

Analytical Methods ◽

10.1039/d0ay02329a ◽

2021 ◽

Author(s):

Arnelle Löbbert ◽

Sonja Schanzer ◽

Henrik Krehenwinkel ◽

Franz Bracher ◽

Christoph Müller

Keyword(s):

Mass Spectrometry ◽

Gas Chromatography ◽

Tandem Mass Spectrometry ◽

Forest Ecosystems ◽

Tandem Mass ◽

Modified Quechers ◽

Chromatography Tandem Mass Spectrometry ◽

The Impact ◽

Impact Of Pesticides

A novel, validated QuEChERS-based GC-MS/MS method was developed, which will allow the assessment of the impact of pesticides on forest ecosystems.

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Mycosporine-Like Amino Acids from Red Macroalgae: UV-Photoprotectors with Potential Cosmeceutical Applications

Applied Sciences ◽

10.3390/app11115112 ◽

2021 ◽

Vol 11 (11) ◽

pp. 5112

Author(s):

Julia Vega ◽

Geniane Schneider ◽

Bruna R. Moreira ◽

Carolina Herrera ◽

José Bonomi-Barufi ◽

...

Keyword(s):

Mass Spectrometry ◽

Amino Acids ◽

High Performance ◽

Nitrogen Availability ◽

Antioxidant Properties ◽

Published Data ◽

Diverse Group ◽

Red Macroalgae ◽

Thermo Stability ◽

The Impact

Macroalgae belong to a diverse group of organisms that could be exploited for biomolecule application. Among the biocompounds found in this group, mycosporine-like amino acids (MAAs) are highlighted mainly due to their photoprotection, antioxidant properties, and high photo and thermo-stability, which are attractive characteristics for the development of cosmeceutical products. Therefore, here we revise published data about MAAs, including their biosynthesis, biomass production, extraction, characterization, identification, purification, and bioactivities. MAAs can be found in many algae species, but the highest concentrations are found in red macroalgae, mainly in the order Bangiales, as Porphyra spp. In addition to the species, the content of MAAs can vary depending on environmental factors, of which solar radiation and nitrogen availability are the most influential. MAAs can confer photoprotection due to their capacity to absorb ultraviolet radiation or reduce the impact of free radicals on cells, among other properties. To extract these compounds, different approaches can be used. The efficiency of these methods can be evaluated with characterization and identification using high performance liquid chromatography (HPLC), associated with other apparatus such as mass spectrometry (MS) and nuclear magnetic resonance (NMR). Therefore, the data presented in this review allow a broad comprehension of MAAs and show perspectives for their inclusion in cosmeceutical products.

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Hyperandrogenism by Liquid Chromatography Tandem Mass Spectrometry in PCOS: Focus on Testosterone and Androstenedione

Journal of Clinical Medicine ◽

10.3390/jcm10010119 ◽

2020 ◽

Vol 10 (1) ◽

pp. 119

Author(s):

Giorgia Grassi ◽

Elisa Polledri ◽

Silvia Fustinoni ◽

Iacopo Chiodini ◽

Ferruccio Ceriotti ◽

...

Keyword(s):

Mass Spectrometry ◽

Liquid Chromatography ◽

Polycystic Ovary ◽

Free Testosterone ◽

Reference Intervals ◽

Model Assessment ◽

Homeostatic Model Assessment ◽

Liquid Chromatography Tandem Mass ◽

And Control ◽

The Impact

The identification of hyperandrogenism in polycystic ovary syndrome (PCOS) is concerning because of the poor accuracy of the androgen immunoassays (IA) and controversies regarding which androgens should be measured. The aim of our study was to evaluate the impact of the assessment of testosterone (T) and androstenedione (A) by liquid chromatography in tandem with mass spectrometry (LC/MS-MS), in the diagnosis of PCOS. We evaluated 131 patients referred for suspected PCOS. Fourteen patients in total were excluded, some because of other diagnosis (n = 7) or incomplete diagnostic workup (n = 7). We measured T and A both by IA and LC-MS/MS in the 117 subjects included. We calculated free T (fT) by the Vermeulen formula and recorded clinical and metabolic data. 73 healthy females served as controls to derive immunoassays (IA) and LC-MS/MS reference intervals for T, fT and A. PCOS was confirmed in 90 subjects by IA and in 93 (+3.3%) by LC-MS/MS. The prevalence of biochemical hyperandrogenism in PCOS by LC-MS/MS increased from 81.7% to 89.2% if A was also considered. The most frequently elevated androgens were fT (73.1%) and A (64.5%) and they had similar levels of accuracy in differentiating PCOS and controls (0.34 ng/dL, Sn 91% Sp 89%; 1.16 ng/mL, Sn 91% Sp 88%, respectively). Free testosterone correlated with body mass index (BMI), homeostatic model assessment (HOMA)-index, glycated hemoglobin (HbA1c), and sex-binding globulin (SHBG). The results confirm that LC-MS/MS is slightly more sensitive than IA in the diagnosis of PCOS with LC-MS/MS detecting higher levels of fT and A. Moreover, assessment of fT and A by LC-MS/MS had a similar level of accuracy in discriminating between PCOs and control subjects. Lastly, fT by LC-MS/MS correlates with adverse metabolic parameters.

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