Phytochemical screening, antibacterial, antioxidant, and cytotoxic activities of Geranium pusillum leaves

Traditional medicinal plants play an important role in primary health care worldwide. The phytochemical screening and activities of Geranium pusillum were investigated in this research. The dried plant leaves were extracted with ethanol, n-hexane, chloroform, dichloromethane, methanol, acetone, and aqueous solvents. These extracts were qualitatively analyzed, GC-MS, antimicrobial activities by using the disc diffusion method, antioxidant activity was determined by 2,2-diphenyl-1-picryl-hydrazyl-hydrate (DPPH) radical scavenging, and cytotoxic activity was analyzed by the hemolytic activity of human red blood cells. The results showed phytochemicals such as flavonoids, terpenoids, steroids, phenols, saponins, tannins, and cardiac glycosides were detected in plant leaves. The ethanol extract at a concentration of 10 mg/mL showed a maximum inhibition zone 17.5 ± 0.09, 15.6 ± 0.11, 14.2 ± 0.17, 18.4 ± 0.11, 16.6 ± 0.15, 12.5 ± 0.13, 15.9 ± 0.10, and 13.1 ± 0.11 mm, and at 15 mg/mL showed 24.5 ± 0.09, 27.2 ± 0.12, 26.3 ± 0.17, 28.4 ± 0.10, 27.9 ± 0.16, 22.5 ± 0.13, 27.1 ± 0.10, and 24.1 ± 0.16 mm against Escherichia coli, Pasturella multocida (gram-negative), Staphylococcus aureus, Bacillus subtilus (gram-positive), Rhizopus solani, Aspergillus flavus, Aspergillus niger, and Alternaria alternate (fungal strain), respectively, and dichloromethane showed a minimum inhibition zone as compared to other extracts against bacterial as well as fungal strains. Chloroform extract had maximum antioxidant activity (45.00 ± 0.08%) and minimum in dichloromethane (12.20 ± 0.04%). Cytotoxic activity was found maximum in acetone extract (19.83 ± 0.07%) and minimum in ethanol extract (4.72 ± 0.04%). It is concluded that phytochemicals like phenols, flavonoids, and others may be responsible for these activities, which is why this plant is used for traditional medicine. RESEARCH HIGHLIGHTS: Geranium pusillum has therapeutic properties that exhibit various biological activities beneficial for human health. G. pusillum has significant inhibitory effects against bacterial and fungal strains. Chloroform solvent extract indicates potential free radical scavenging abilities. Acetone extract exhibits notable effects on human red blood cells and demonstrates significant cytotoxic activity.

Computational investigation of Moringa oleifera phytochemicals targeting EGFR: molecular docking, molecular dynamics simulation and density functional theory studies

Epidermal growth factor receptor (EGFR) is a prominent target for anticancer therapy due to its role in activating several cell signaling cascades. Clinically approved EGFR inhibitors are reported to show treatment resistance and toxicity, this study, therefore, investigates Moringa oleifera phytochemicals to find potent and safe anti-EGFR compounds. For that, phytochemicals were screened based on drug-likeness and molecular docking analysis followed by molecular dynamics simulation, density functional theory analysis and ADMET analysis to identify the effective inhibitors of EGFR tyrosine kinase (EGFR-TK) domain. Known EGFR-TK inhibitors (1-4 generations) were used as control. Among 146 phytochemicals, 136 compounds showed drug-likeness, of which Delta 7-Avenasterol was the most potential EGFR-TK inhibitor with a binding energy of -9.2 kcal/mol followed by 24-Methylenecholesterol (-9.1 kcal/mol), Campesterol (-9.0 kcal/mol) and Ellagic acid (-9.0 kcal/mol). In comparison, the highest binding affinity from control drugs was displayed by Rociletinib (-9.0 kcal/mol). The molecular dynamics simulation (100 ns) exhibited the structural stability of native EGFR-TK and protein-inhibitor complexes. Further, MM/PBSA computed the binding free energies of protein complex with Delta 7-Avenasterol, 24-Methylenecholesterol, Campesterol and Ellagic acid as -154.559 ± 18.591 kJ/mol, -139.176 ± 19.236 kJ/mol, -136.212 ± 17.598 kJ/mol and -139.513 ± 23.832 kJ/mol, respectively. Non-polar interactions were the major contributors to these energies. The density functional theory analysis also established the stability of these inhibitor compounds. ADMET analysis depicted acceptable outcomes for all top phytochemicals without displaying any toxicity. In conclusion, this report has identified promising EGFR-TK inhibitors to treat several cancers that can be further investigated through laboratory and clinical tests.

Molecular Docking Study on Several Benzoic Acid Derivatives against SARS-CoV-2

Several derivatives of benzoic acid and semisynthetic alkyl gallates were investigated by an in silico approach to evaluate their potential antiviral activity against SARS-CoV-2 main protease. Molecular docking studies were used to predict their binding affinity and interactions with amino acids residues from the active binding site of SARS-CoV-2 main protease, compared to boceprevir. Deep structural insights and quantum chemical reactivity analysis according to Koopmans’ theorem, as a result of density functional theory (DFT) computations, are reported. Additionally, drug-likeness assessment in terms of Lipinski’s and Weber’s rules for pharmaceutical candidates, is provided. The outcomes of docking and key molecular descriptors and properties were forward analyzed by the statistical approach of principal component analysis (PCA) to identify the degree of their correlation. The obtained results suggest two promising candidates for future drug development to fight against the coronavirus infection.