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401.
Ezzouhra El Maaiden Sarah Bouzroud Boubker Nasser Khadija Moustaid Ayoub El Mouttaqi Mohamed Ibourki Hassan Boukcim Abdelaziz Hirich Lamfeddal Kouisni Youssef El Kharrassi 《Molecules (Basel, Switzerland)》2022,27(7)
This study aimed to compare the influence of extraction methods on the pharmaceutical and cosmetic properties of medicinal and aromatic plants (MAPs). For this purpose, the dried plant materials were extracted using advanced (microwave (MAE), ultrasonic (UAE), and homogenizer (HAE) assisted extractions) and conventional techniques (maceration, percolation, decoction, infusion, and Soxhlet). The tyrosinase, elastase, α-amylase, butyryl, and acetylcholinesterase inhibition were tested by using L-3,4 dihydroxy-phenylalanine, N-Succinyl-Ala-Ala-p-nitroanilide, butyryl, and acetylcholine as respective substrates. Antioxidant activities were studied by ABTS, DPPH, and FRAP. In terms of extraction yield, advanced extraction techniques showed the highest values (MAE > UAE > HAE). Chemical profiles were dependent on the phenolic compounds tested, whereas the antioxidant activities were always higher, mainly in infusion and decoction as a conventional technique. In relation to the pharmaceutical and cosmetic properties, the highest inhibitory activities against α-amylase and acetylcholinesterase were observed for Soxhlet and macerated extracts, whereas the highest activity against tyrosinase was obtained with MAE > maceration > Soxhlet. Elastase and butyrylcholinesterase inhibitory activities were in the order of Soxhlet > maceration > percolation, with no activities recorded for the other tested methods. In conclusion, advanced methods afford an extract with high yield, while conventional methods might be an adequate approach for minimal changes in the biological properties of the extract. 相似文献
402.
Nessreen S. Abdelhamid Maimana A. Magdy Basma H. Anwar Nehal F. Farid 《Biomedical chromatography : BMC》2022,36(5):e5343
Recently, prednisolone has been used in treating many medical conditions, such as autoimmune diseases and cancer. It is also prescribed to mitigate the respiratory complications caused by COVID-19 infection. It can cause some health complications, such as GIT ulcers, so it should be co-administered with proton-pump inhibitors, such as esomeprazole, to prevent the risk of ulcers. This work aims to develop an ecofriendly and sensitive TLC method for simultaneous determination of esomeprazole and prednisolone in their binary mixtures and spiked human plasma. Separation was performed using a mixture of ethyl acetate, methanol, and ammonia (9.5:0.5:0.1, v/v/v) as an eluting system with UV scanning at 245 nm. Dapoxetine was used as an internal standard to correct the variation during sampling. The resulting Rf values for plasma, esomeprazole, prednisolone, and dapoxetine were 0.03, 0.51, 0.72 and 0.85, respectively. Four greenness assessment tools—national environmental method index, eco-scale assessments, analytical greenness metric approach (AGREE), and green analytical procedure index (GAPI)—were used to evaluate the greenness characteristics of the proposed method to the environment, and the results were acceptable and satisfactory. Validation parameters were checked according to the US FDA guidelines to achieve the international requirements for bioanalytical method validation, and the results were within the accepted ranges. 相似文献
403.
Mohamed Magdy Khalil Yousry Mostafa Issa Sahar Mahmoud Mostafa 《Journal of the Iranian Chemical Society》2017,14(9):1993-2005
The fabrication and electrochemical response characteristics of four novel potentiometric sensors for determination of pyrilamine maleate (PyraH) were described. The sensors include polymeric membrane electrodes (PME1, PME2) and carbon paste electrodes (CPE1, CPE2). The fabricated sensors were based on the ion-pair of pyrilamine with sodium tetraphenylborate (NaTPB) and ammonium reineckate (NH4RN) using dibutyl phthalate (DBP) as plasticizing solvent. The sensors showed linear, stable and near-Nernstian slopes of 56.4 ± 0.4, 54.2 ± 0.2, 58.8 ± 0.3 and 57.9 ± 0.4 mV decade?1 at 25 ± 0.1 °C and detection limits of 2.0 × 10?5, 1.8 × 10?5, 1.0 × 10?5 and 9.5 × 10?6 mol L?1 for PME1, PME2, CPE1 and CPE2 sensors, respectively. The response time was less than 10 and 8 s for polymeric membrane and carbon paste sensors. The proposed sensors displayed good selectivity for pyrilamine with respect to a number of common inorganic and organic species. The thermal temperature coefficients of the investigated sensors were 0.9508, 0.7012, 0.9450 and 0.6497 mV °C?1. Modified carbon paste sensors showed lower detection limits, higher thermal stability and faster response time than those of polymeric membrane sensors. The proposed sensors displayed useful analytical characteristics for determination of pyrilamine in pharmaceutical preparation and biological fluids (Human urine and plasma). 相似文献
404.
Aaya Nassar Ibrahim M. Ibrahim Fatma G. Amin Merna Magdy Ahmed M. Elgharib Eman B. Azzam Filopateer Nasser Kirllos Yousry Israa M. Shamkh Samah M. Mahdy Abdo A. Elfiky 《Molecules (Basel, Switzerland)》2021,26(21)
A novel human coronavirus prompted considerable worry at the end of the year 2019. Now, it represents a significant global health and economic burden. The newly emerged coronavirus disease caused by the severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) is the primary reason for the COVID-19 global pandemic. According to recent global figures, COVID-19 has caused approximately 243.3 million illnesses and 4.9 million deaths. Several human cell receptors are involved in the virus identification of the host cells and entering them. Hence, understanding how the virus binds to host-cell receptors is crucial for developing antiviral treatments and vaccines. The current work aimed to determine the multiple host-cell receptors that bind with SARS-CoV-2 and other human coronaviruses for the purpose of cell entry. Extensive research is needed using neutralizing antibodies, natural chemicals, and therapeutic peptides to target those host-cell receptors in extremely susceptible individuals. More research is needed to map SARS-CoV-2 cell entry pathways in order to identify potential viral inhibitors. 相似文献
405.
Dr. Brahim Ait Addi Prof. Brahim El Ibrahimi Prof. Abdelaziz Ait Addi Dr. Abdul Shaban Prof. El-Habib Ait Addi Prof. Mohamed Hamdani 《Electroanalysis》2021,33(3):804-819
The influence of hydrogen phosphate (HPO42−) and molybdate ions (MoO42−) on the behavior of tin corrosion in 0.2 M maleic acid was compared using experimental and theoretical techniques. The experimental studies consisted of the electrochemical investigations (potentiodynamic polarization (PDP) and electrochemical impedance spectroscopy (EIS)), along with the surface analytical techniques (SEM and EDX). Additionally, the theoretical analysis (the chemical quantum computations at MP4/SDD level of theory in the aqueous phase), was conducted. The experimental outcomes illustrated that the inhibition efficiency (η%) increases with the concentration of the inhibitors, reaching 88 % and 81 % at 2×10−2 M concentration of MoO42− and HPO42−, respectively. The potentiodynamic polarization curves revealed that HPO42− performance is a cathodic-type inhibitor, while MoO42− shows a mixed-type behavior. The increase in temperature decreased the η% values of both inhibitors. Based on surface analysis and thermodynamic study, the presence of the two inhibitors formed protective films on the tin surface through a physisorption mechanism. The chemical quantum computations using the complete fourth-order Møller Plesset perturbation theory (MP4 with SDD basis) method results outlined the favorable affinity of the investigated inorganic inhibitors to interact with the tin surface, which interprets the well-observed inhibition efficiencies. 相似文献
406.
Ahmed S. A. Youssef Magdy M. Hemdan Mohammad E. Azab Samir A. Emara Galal A. Elsayed Rabaa M. Kamel 《Journal of heterocyclic chemistry》2020,57(3):1133-1142
Syringaldehyde was utilized in synthesis of different heterocyclic systems. Some of the synthesized compounds 2 , 7 , 8 , 10 , 11 , and 13 were tested for antioxidant activity where they showed ability to inhibit oxidation in kidney and rat brain homogenates using 2, 2′-azinobis (3-ethylbenzothiazoline-6-sulfonic acid) (ABTS). Also, the activity against cancer was examined using the standard MTT method for two human tumor cell lines namely; mammary gland breast cancer MCF-7 and hepatocellular carcinoma HepG2. The highest activity as antioxidant and antitumor agents was exhibited by compounds 8 and 11 . However, moderate activities were shown by compounds 10 and 13 . While, compounds 2 , 7 showed weak activities. 相似文献
407.
Synthesis of Heteroannulated Chromeno[2,3‐b]Pyridines: DBU Catalyzed Reactions of 2‐Amino‐6‐methylchromone‐3‐Carboxaldehyde with Some Heterocyclic Enols and Enamines 下载免费PDF全文
Magdy A. Ibrahim Nasser M. El‐Gohary Sara Said 《Journal of heterocyclic chemistry》2016,53(1):117-120
New series of heteroannulated chromeno[2,3‐b]pyridines were easily and efficiently synthesized from DBU‐catalyzed condensation of 2‐amino‐6‐methylchromone‐3‐carboxaldehyde with a variety of heterocyclic enols and enamines, namely, 4‐hydroxycoumarin, 4‐hydroxy‐1‐methylquinolin‐2(1H)‐one, 2‐hydroxy‐4H‐pyrido[1,2‐a]pyrimidin‐4‐one, 4‐hydroxy‐2H‐pyrano[3,2‐c]quinoline‐2,5(6H)‐dione, 4(6)‐aminouracil and 5‐amino‐3‐methyl‐1H‐pyrazole. Structures of the new synthesized products were deduced on the basis of their analytical and spectral data. 相似文献
408.
The water‐soluble rhodium complex generated in situ from [Rh (COD)Cl]2 in aqueous ammonia has been revealed as a highly efficient catalyst for the hydrogenation of aromatic nitriles, to primary amines with excellent yields. The catalyst is also highly selective towards primary amines in the case of sterically hindered aliphatic nitriles. The catalytic system can also be recycled and re‐used with no significant loss of activity. 相似文献
409.
410.