Main protease (Mpro) of SARS-CoV-2 is a key CoV enzyme that plays a pivotal role in mediating viral replication and transcription, making it an attractive drug target for SARS-CoV-2 the new strain of coronavirus. In this study, we evaluated biologically active compounds present in medicinal plants as potential SARS-CoV-2 Mpro inhibitors, using a molecular docking study with Autodock Vina software. Top seven compounds Afzelin, Phloroglucinol, Myricetin-3-O- rutinosid Tricin 7-neohesperidoside, Silybin, Kaempferol and Silychristin among 50 molecules of natural Origin (Algerian Medicinal plants) were selected which had better and significantly low binding energy as compared to the reference molecule with binding affinities of −9.3, −9.3, −9, −8.9, −8.5, 8.3 and −8.3 kcal mol⁻¹ respectively. Then, we analyzed the ADME properties of the best 7 ligands using the Web server SwissADME. Two of small molecules have been shown to be the ideal candidates for further drug development. Finally, the stability of the both compounds complexed with Mpro was validated through molecular dynamics (MD) simulation, they displayed stable trajectory (RMSD, RMSF) and molecular properties with consistent interaction profile in molecular dynamics simulations, moreover, Silybin could form more stable complex with Mpro than Silychristin. Communicated by Ramaswamy H. Sarma

Electrochemistry characterization of ferrocene/ferricenium redox couple at glassycarbon electrode

The enzyme Leucine-rich repeat kinase 2 (LRRK2) has become a target of therapeutic interest in Parkinson research.Athree-dimensional quantitative structure-activity relationships(3D-QSAR) study was performed on twenty six azaindazole derivatives as LRRK2 inhibitorsobtained using rigid body alignment (Distill). CoMFA and CoMSIA model shave achieved high activity-descriptor relationship efficiency of 96% and 93% as shown by the regression-coefficient (R²=0.961 and 0.933) and were found statistically significant with cross validated coefficient (Q²_CV= 0.625 and 0.554), respectively.3D-QSAR models were externally validated by a test set of sixbioactive compounds showing satisfactory predicted correlation coefficient (R²_pred) of 0.865 and 0.853 for CoMFA and CoMSIA models, respectively. Besides, Y-randomization test was also performed to ensure the robustness of the obtained3D-QSAR models. This study provides valuable clues to design new compounds against LRRK2. Docking studies suggested that the ligand (new designed compound C2) has more potential than the ligand of reference 4K4 and confirm the obtained results from 3D-QSAR studies. Furthermore, the newly designed compounds and ligand of reference 4K4 were analyzed for their ADMET properties and drug likeness. These results would be of great help in leading optimization for developing new anti-Parkinson drug. Communicated by Ramaswamy H. Sarma Graphical Abstract

In the present research, we studied the quantification of the total phenolics, total flavonoids, total flavonols, and the evaluation of the antioxidant activity of the fruits of Solanum nigrum L. by chemical and electrochemical methods. The chloroform, ethyl acetate, and n-butanol crude extracts are prepared from the hydroethanolic extract of the fruits were tested. The results showed that ethyl acetate extract showed the highest phenolic content (87.68mg GAE/g), chloroform extract showed the highest flavonoid content (24.23mg QE/g) and highest flavonol content (71.60mg RE/g). The evaluation of antioxidant activity by chemical methods revealed that the highest DPPH radical scavenging activity was shown by ethyl acetate extract (0.123mg/mL) while the highest ferric reducing capacity was shown by butanol extract (610.46±0.0015mg FeSO4/g). The electrochemical study of the three extracts by cyclic voltammetry method indicates that the highest antioxidant activity was shown by ethyl acetate extract (17.75±0.238mg/g) equivalent ascorbic acid. The superoxide scavenging assay of chloroform extract showed the highest value (0.8 mg/mL).

Chemical composition and antioxidant activity of Apis mellifera bee pollen from northwest Algeria