mass spectrometry technique
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2022 ◽  
Author(s):  
Wei-Chien Weng ◽  
Hun-En Liao ◽  
Shih-Pei Huang ◽  
Shang-Ting Tsai ◽  
Hsu-Chen Hsu ◽  
...  

Free oligosaccharides are abundant macronutrients in milk and involved in prebiotic functions and antiadhesive binding of pathogenic bacteria to colonocytes. Despite the importance of these oligosaccharides, structural determination of oligosaccharides is challenging, and milk oligosaccharide biosynthetic pathways remain unclear. Oligosaccharide structures are conventionally determined using a combination of chemical reactions, exoglycosidase digestion, nuclear magnetic resonance spectroscopy, and mass spectrometry. Most reported free oligosaccharides are highly abundant and have lactose at the reducing end, and current oligosaccharide biosynthetic pathways in human milk are proposed based on these oligosaccharides. In this study, a new mass spectrometry technique, which can identify linkages, anomericities, and stereoisomers, was applied to determine the structures of free oligosaccharides in human, bovine, and caprine milk. Oligosaccharides that do not follow the current biosynthetic pathways and are not synthesized by any discovered enzymes were found, indicating the existence of undiscovered biosynthetic pathways and enzymes. New biosynthetic pathways were proposed.


Foods ◽  
2021 ◽  
Vol 10 (12) ◽  
pp. 3103
Author(s):  
Efraín Acosta-Salazar ◽  
Rocío Fonseca-Aguiñaga ◽  
Walter M. Warren-Vega ◽  
Ana I. Zárate-Guzmán ◽  
Marco A. Zárate-Navarro ◽  
...  

Due to the oversupply and scarcity cycles of the Agave tequilana Weber blue variety, the effect of agave age (harvested in 4, 5, and 6 years) as raw material for the tequila 100% agave silver class was studied for each stage in a full-scale (industrial) process. Harvested plants showed differences in their morphological characteristics that affected the amount of juice; this had an impact in the fermentation stage since must composition was modified in the nitrogen content and juice/exudate ratio. This was noticed due to an increase in the production of higher alcohols attributed to the odd-chain fatty of the exudate, which affects n-propanol production. The characterization of the final product showed the feasibility to use agaves (less than 7 years) to produce the Tequila 100% agave silver class and to comply with the quality criteria. Furthermore, the final product was analyzed with the gas chromatography-isotope ratio mass-spectrometry technique to determine its authenticity. The δ13CVPDB isotopic parameter (−13.40‰ in average) values show the type of plant used as a raw material for ethanol production, while the δ18OVSMOW (20.52‰ in average) isotopic parameter can be helpful in corroborating and ensuring the traceability of the product and the geographical location of the beverage production.


2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Joanna Wojtkiewicz ◽  
Manolis Tzatzarakis ◽  
Elena Vakonaki ◽  
Krystyna Makowska ◽  
Slawomir Gonkowski

AbstractParabens (PBs) are a group of substances commonly used in industry. They also pollute the environment, penetrate into living organisms and adversely affect various internal organs. During this study, the degree of exposure of people living in Olsztyn, a city in north eastern Poland, to selected parabens most often used in industry was studied. The chemicals under investigation included: methyl paraben—MePB, ethyl paraben—EtPB, propyl paraben—PrPB, benzyl paraben BePB and butyl paraben -BuPB. To this aim, hair samples collected from the scalps of 30 volunteers were analyzed using a liquid chromatography–mass spectrometry technique. All PBs studied were present in a high percentage of analyzed samples (from 76.7% in the case of BePB to 100% in the case of MePB and PrPB). The mean concentration levels were 4425.3 pg/mg for MeBP, 704.0 pg/mg for EtPB, 825.7 pg/mg for PrPB, 135.2 pg/mg for BePB and 154.5 pg/mg for BuPB. Significant differences in PB concentration levels between particular persons were visible. On the other hand, gender, age and artificial hair coloring did not cause statistically significant differences in PB levels. Obtained results have clearly indicated that people living in north eastern Poland are exposed to various PBs, and therefore these substances may affect their health status. However, the evaluation of PBs influence on human health requires further research.


2021 ◽  
Vol 12 ◽  
Author(s):  
Lihua Yao ◽  
Qin Wang ◽  
Runjie Zhang ◽  
Xingyun Wang ◽  
Yiwen Liu ◽  
...  

Polycystic ovary syndrome (PCOS) is a complex reproductive, endocrine, and metabolic disorder in reproductive-age women. In order to explore the active metabolites of brown adipose tissue (BAT) transplantation in improving the reproductive and metabolic phenotypes in a PCOS rat model, the metabolites in the recipient’s BAT were explored using the liquid chromatography–mass spectrometry technique. In total, 9 upregulated and 13 downregulated metabolites were identified. They were roughly categorized into 12 distinct classes, mainly including glycerophosphoinositols, glycerophosphocholines, and sphingolipids. Ingenuity pathway analysis predicted that these differentially metabolites mainly target the PI3K/AKT, MAPK, and Wnt signaling pathways, which are closely associated with PCOS. Furthermore, one of these differential metabolites, sphingosine belonging to sphingolipids, was randomly selected for further experiments on a human granulosa-like tumor cell line (KGN). It significantly accelerated the apoptosis of KGN cells induced by dihydrotestosterone. Based on these findings, we speculated that metabolome changes are an important process for BAT transplantation in improving PCOS. It might be a novel therapeutic target for PCOS treatment.


2021 ◽  
Vol 11 (12) ◽  
pp. 1561
Author(s):  
Igor Manzhulo ◽  
Olga Manzhulo ◽  
Anna Tyrtyshnaia ◽  
Arina Ponomarenko ◽  
Sophia Konovalova ◽  
...  

The present study demonstrates that synaptamide (N-docosahexaenoylethanolamine), an endogenous metabolite of docosahexaenoic acid, when administered subcutaneously (4 mg/kg/day, 14 days), exhibits analgesic activity and promotes cognitive recovery in the rat sciatic nerve chronic constriction injury (CCI) model. We analyzed the dynamics of GFAP-positive astroglia and S100β-positive astroglia activity, the expression of nerve growth factor (NGF), and two subunits of the NMDA receptor (NMDAR1 and NMDAR2A) in the hippocampi of the experimental animals. Hippocampal neurogenesis was evaluated by immunohistochemical detection of DCX. Analysis of N-acylethanolamines in plasma and in the brain was performed using the liquid chromatography-mass spectrometry technique. In vitro and in vivo experiments show that synaptamide (1) reduces cold allodynia, (2) improves working memory and locomotor activity, (3) stabilizes neurogenesis and astroglial activity, (4) enhances the expression of NGF and NMDAR1, (5) increases the concentration of Ca2+ in astrocytes, and (6) increases the production of N-acylethanolamines. The results of the present study demonstrate that synaptamide affects the activity of hippocampal astroglia, resulting in faster recovery after CCI.


Foods ◽  
2021 ◽  
Vol 10 (11) ◽  
pp. 2549
Author(s):  
Antonella Verzera ◽  
Maria Merlino ◽  
Fabrizio Cincotta ◽  
Ottavia Prestia ◽  
Antonio Sparacio ◽  
...  

Vitis vinifera L. cv. Moscato includes different varieties mainly used to produce sweet wines, such as fortified wines. Moscato grapes are characterized by a large number of free and glycosylated monoterpenoids giving very aromatic wines. However, the literature data on the aroma profile of fortified Moscato wines are very limited. In light of this, the present research aimed to investigate the aroma compounds, mainly the varietal ones, of fortified wines from different Moscato varieties, namely Giallo (Yellow), Bianco (White), Bianco at Petit Grain (Blanc à Petits Grains), Ottonel and Rosa (Pink of Trentino), cultivated under the same pedoclimatic conditions. Using the HS-SPME-GC-MS (head space-solid phase micro extraction-gas chromatography-mass spectrometry) technique, numerous varietal and fermentative aroma compounds have been identified and quantified and significant differences were observed among varieties in the levels of mostly volatiles and in their ratios. Based on their composition, the studied wines can be divided in two groups depending on whether linalool or geraniol prevails among varietal aromas. These results are evidence that each Moscato variety has a typical varietal aroma composition, even if some similarities were found between the two white varieties, and between Moscato Giallo and Moscato Ottonel varieties. Moscato Rosa showed a peculiar aroma composition and the lowest ester/terpene ratio.


2021 ◽  
Vol 2045 (1) ◽  
pp. 012024
Author(s):  
X Y Du ◽  
X Y Liu ◽  
Z Y Shang ◽  
W S Han ◽  
H Zhang

Abstract In order to clarify the necessity and urgency of dioxin detection, the characteristics and emission sources were firstly studied in this paper. The current dioxin detection techniques were then summarized, including chemical detection technique represented by HRGC/MS, biological detection technique covering immunology and biotechnology, and laser mass spectrometry technique using fusion ionization technology and time-of-flight mass spectrometry. Then the advantages and disadvantages, representative technologies, development directions and application prospects of various detection methods were analyzed. Eventually, the future development direction of dioxin detection technology was prospected.


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