magnetic resonance spectroscopic analysis
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Author(s):  
F. O. Taiwo ◽  
C. A. Obafemi ◽  
E. M. Obuotor ◽  
I. J. Olawuni

Aims: To synthesize some phthalimides derivatives and evaluate the compounds for their possible biological properties. Methods: The substituted phenylisoindoline-1,3-dione were synthesized from the reactions of N-phenyl phthalimide with different substituted aromatic aldehyde. The synthesized compounds were characterized using nuclear magnetic resonance spectroscopic analysis. The acetylcholinesterase and butyryl cholinesterase inhibitions were determined by Spectro photochemical analysis of acetylthiocholine and butyryl choline chloride. Results: Compounds 6 (IC50 = 30±3 µg/mL) and 4 (IC50 = 141±60 µg/mL) were found to be the most active inhibitors against acetylcholinesterase, while compounds 4 (IC50 = 102±10 µg/mL), 5 (IC50 = 105 ± 20 µg/mL) and 2 (IC50 = 190 ± 10 µg/mL), were found to be most active inhibitor against butyryl cholinesterase. Conclusion: The considerable acetylcholinesterase and butyryl cholinesterase inhibitory activities of the synthesized compounds makes them good candidates for the development of selective acetylcholinesterase and butyryl cholinesterase inhibitors.


Author(s):  
F. O. Taiwo ◽  
C. A. Obafemi ◽  
E. M. Obuotor ◽  
I. J. Olawuni

Aims: To synthesize some phthalimides derivatives and evaluate the compounds for their possible biological properties. Methods: The substituted phenylisoindoline-1,3-dione were synthesized from the reactions of N-phenyl phthalimide with different substituted aromatic aldehyde. The synthesized compounds were characterized using nuclear magnetic resonance spectroscopic analysis. The Nitric oxide and Ferric reducing antioxidant properties (FRAP) were determined by spectrophochemical method. Results: The IC50 values for all the synthesized compounds were lower than standard, eserine (IC50 = 15 ± 2 µg/mL) against Nitric oxide inhibition. Compounds 3 (FRAP = 205±8 µg/ML) and 6 (FRAP = 118±1 µg/ML) were found to exhibit higher FRAP analysis results which were comparable to the results obtained for serine. (FRAP = 202±7 µg/ML). Conclusion: The considerable activity of the compounds shown by its Nitric oxide and Ferric reducing antioxidant properties (FRAP) makes them good candidates for the development of selective acetylcholinesterase and butyryl cholinesterase inhibitors.


2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Mary R. Arenberg ◽  
Yuji Arai

AbstractAs an essential component of enzymes, higher N availability from agricultural runoff to forest soils may boost the activity of phosphatase, increasing the bioavailability of phosphate. The objective of this study was to evaluate P mineralization rates in temperate floodplain soils as a function of inorganic N species (i.e., ammonium and nitrate) and amendment rate (1.5–3.5 g N kg−1). Accordingly, the soil was amended with nitrate and ammonium, and P dynamics were monitored during a 40-day incubation. The addition of ammonium significantly boosted acid and alkaline phosphatase activity by 1.39 and 1.44 µmol p-nitrophenol P (pNP) g−1 h−1, respectively. The degree of increase was positively correlated with the amendment rate. Likewise, the P mineralization rate increased by 0.27 mg P kg−1 in the 3.5 g N kg−1 ammonium treatment. 31P nuclear magnetic resonance spectroscopic analysis further supported the reduction in organic orthophosphate diesters on day 30. Meanwhile, the addition of nitrate promoted P mineralization to a lesser degree but did not increase phosphatase activity. While floodplain soils have great potential to sequester anthropogenic P, high availability of inorganic N, especially ammonium, could promote P mineralization, potentially increasing P fertility and/or reducing P the sequestration capacity of floodplain soils.


2020 ◽  
Author(s):  
Rana Halloun ◽  
Ahmad Ighbariya ◽  
Suhair Hanna ◽  
Ronit Sinnreich ◽  
Ram Weiss

Abstract Background: Palestinians exhibit a substantially greater prevalence of type 2 diabetes mellitus, cardiovascular disease (CVD) incidence and CVD mortality in comparison to Israelis. In view of Palestinians' increased insulin resistance, known to be associated with an adverse lipoprotein profile, we aimed at showing lipoprotein variations between Palestinian and Israelis residing in Jerusalem. Methods: The study included, 968 Palestinians and 707 Israelis, ages 25-74 years, who underwent fasting and 2h post oral challenge plasma glucose determinations. We evaluated metabolic risk by measuring sub-populations of VLDL, LDL and HDL particles, using nuclear magnetic resonance spectroscopic analysis. Results: Palestinians exhibit higher levels of very large VLDL including chylomicrons, in comparison to their Israeli counterparts, whereas levels of medium and small VLDL were similar between the two populations. Small oxidized LDL levels were higher among Palestinians while intermediate and large LDL were similar between the two groups. Levels of large HDL were higher among Israelis while levels of medium and small HDL were similar between the two populations. Small oxidized LDL levels were higher among Palestinians in comparison to Israeli participants. Levels of large HDL were higher among Israelis in comparison to Palestinians. Limiting the analysis to young participants with normal glucose tolerance, showed greater levels of large VLDL including chylomicrons, medium and small VLDL and oxidized LDL in Palestinians. Conclusions: Palestinians, including healthy young participants, exhibit an adverse pro-atherogenic lipid profile compared to Israelis. These findings may explain the increased CVD morbidity and mortality observed in Palestinians.


2020 ◽  
Vol 10 (1) ◽  
Author(s):  
S. Manjunath Kamath ◽  
K. Sridhar ◽  
D. Jaison ◽  
V. Gopinath ◽  
B. K. Mohamed Ibrahim ◽  
...  

Abstract Modulation of initial burst and long term release from electrospun fibrous mats can be achieved by sandwiching the drug loaded mats between hydrophobic layers of fibrous polycaprolactone (PCL). Ibuprofen (IBU) loaded PCL fibrous mats (12% PCL-IBU) were sandwiched between fibrous polycaprolactone layers during the process of electrospinning, by varying the polymer concentrations (10% (w/v), 12% (w/v)) and volume of coat (1 ml, 2 ml) in flanking layers. Consequently, 12% PCL-IBU (without sandwich layer) showed burst release of 66.43% on day 1 and cumulative release (%) of 86.08% at the end of 62 days. Whereas, sandwich groups, especially 12% PCLSW-1 & 2 (sandwich layers—1 ml and 2 ml of 12% PCL) showed controlled initial burst and cumulative (%) release compared to 12% PCL-IBU. Moreover, crystallinity (%) and hydrophobicity of the sandwich models imparted control on ibuprofen release from fibrous mats. Further, assay for cytotoxicity and scanning electron microscopic images of cell seeded mats after 5 days showed the mats were not cytotoxic. Nuclear Magnetic Resonance spectroscopic analysis revealed weak interaction between ibuprofen and PCL in nanofibers which favors the release of ibuprofen. These data imply that concentration and volume of coat in flanking layer imparts tighter control on initial burst and long term release of ibuprofen.


2020 ◽  
Vol 15 (8) ◽  
pp. 1934578X2094128
Author(s):  
Yuxiang Ma ◽  
Benguo Liu

Phenolic acid-polysaccharide conjugates, produced in plant food and medicine processing, are thought to account for the α-glucosidase inhibitory activity of the final products. However, this speculation lacks experimental support because of the complexity of the plant system and the polysaccharide structure. In this study, with dextran (average molecular weight, 1000) as the skeleton, a gallic acid-dextran conjugate was synthesized and confirmed by ultraviolet, infrared, and nuclear magnetic resonance spectroscopic analysis for the first time. Furthermore, this gallic acid-dextran conjugate showed inhibition of α-glucosidase due to galloyl groups in a mixed competitive and noncompetitive inhibition mode, whose performance was superior to that of acarbose.


Author(s):  
Vo Viet Dai Vo

1,5-Disubstituted 1,2,3-triazoles are synthesized viametal-free multi-component reaction from primary amine, ketones and 4-nitrophenyl azide. The structure of three target compounds including:1-(4-methoxybenzyl)-5-(4-methylphenyl)-1H-1,2,3-triazole (1), 1-(4-methoxybenzyl)-5-(4-nitrophenyl)-1H-1,2,3-triazole (2) and 1-(4-methoxybenzyl)-5-phenyl-1H-1,2,3-triazole (3) is elucidated and identified by infrared spectroscopy, nuclear magnetic resonance spectroscopic analysis and high resolution mass spectrum. The formation of heterocyclic aromatic 1,2,3-triazole ring is approved by the appearance of singlet peak at 7.71 ppm in 1H NMR corresponding with triazolyl proton. In addition, antibacterial and antifungal activities of products are also tested with three Gram-positive bacteria (B. subtilis, S. aureus and L. fermentum), three Gram-negative bacteria (P. aeruginosa, E.coli, S. enterica), and Candida albicans fungus.


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