Modern Scientific Press

ABSTRACT: Physalis peruviana L has been reported in traditional medicine for the treatment of bacterial, fungal, viral, protozoal diseases, as well as possessing immunomodulatory properties. The aim of this study was to assess the antibacterial and antifungal properties of various parts of methanolic P. peruviana extracts against 6 bacterial species and 2 fungal isolates. Antibacterial and antifungal activity of methanolic P. peruviana leaves, stem, fruit and root extracts were evaluated in vitro by agar diffusion method against Escherichia coli ATCC 25922, Staphylococcus aureus ATCC 25923, Klebsiella pneumonia local isolate, Salmonella typhi ATCC 700931, Pseudomonas aeruginosa ATCC 27853, Bacillus cereus ATCC 11778, Candida albicans ATCC 90028 and Aspergillus flavus local isolate. Minimum bactericidal concentration was carried out using the tube microdilution method. All P. peruviana methanolic extracts were also investigated for phytochemical components. Phytochemical investigation on methanolic P. peruviana extracts revealed the presence of tannins, saponins, flavonoids, and alkaloids. Statistical analysis for intra-group inhibitory activity amongst the various methanolic P. peruviana extracts concentrations demonstrated significant differences (P < 0.05) that were dose-dependent. The minimum inhibitory concentration and minimum microbicidal concentration against the test bacteria and fungi ranged from 3.9 to 62.5 mg/ml. Methanolic P. peruviana leaves extracts were the most potent against E. coli, S. typhi, P. aeruginosa and B. cereus. All P. peruviana extracts exhibited antibacterial and antifungal potential and can be considered as possible sources of noble antimicrobial agents for treating bacterial and fungal infections.

ABSTRACT: Coronaviruses are dangerous micro-organism that attacks both the young and adults. Some are responsible for trifling diseases that occur in human respiratory organ while the famous ones (severe acute respiratory syndrome (SARS) and Middle East respiratory syndrome (MERS)) are very dangerous and are capable of causing terrible respiratory disease. In a way to inhibit this life threatening virus, five molecular compounds obtained from Annona Muricata Seed which has been helpful to human being were studied via density functional theory method using Spartan, Discovery studio, AutoDock Tool, AutoDock Vina and Edupymol. In this study, the calculated descriptors (highest occupied molecular orbital energy (EHOMO), lowest unoccupied molecular orbital energy (ELUMO), dipole moment, energy band gap, area, volume, polarizability, polar surface area, Log P, hydrogen bond donor, hydrogen bond acceptor) obtained from optimized compounds were observed to describe anti-SARS-CoV nsp12 polymerase. Also, the docking study exposed the inhibiting ability of the studied compounds. The calculated binding affinity are -5.1 kcal/mol, -4.5 kcal/mol, -4.4 kcal/mol, -5.6 kcal/mol, and -4.7 kcal/mol for compounds A-E and it was observed that the calculated binding affinity values were closer and this is sign that the selected compounds in Annona Muricata seed are promising anti-SARS-CoV nsp12 polymerase. Therefore, the selected compounds from Annona Muricata seed have a promising ability to inhibit SARS-CoV nsp12 polymerase thereby inhibiting 2019-nCoV.

ABSTRACT: There is presently a global trend of serious problem of increasing antimicrobial resistance caused by extensive abuse and over-use of antibiotics, leading to crucial need to develop alternative antibiotics. The leaf of Dacryodes edulis was extracted with absolute Acetone, partitioned and mechanism of actions was determined by rate of kill (ROK) assay and leakages of cellular components by the active fractions. The extract was partitioned using Separatory funnel. The antibacterial assessment of crude extract and fractions was determined by agar well diffusion; minimum inhibitory concentration (MIC) and MBC by broth dilution and agar diffusion methods respectively. The leakages of protein, nucleotide and potassium ions by the active fractions were determined using Staphylococcus aureus and Escherichia coli as representatives of Gram positive and Gram negative bacteria respectively. The results showed that the crude extract and fractions possess broader antibacterial spectrum and greater antibacterial activities against all the tested bacterial than standard antibiotics. The minimum inhibitory concentrations of the crude extract ranged between 1.56 and 6.25 mg/mL while those of aqueous (AQU) and dichloromethane (DCM) fractions ranged between 0.78 mg/mL and 3.12 mg/mL. The rate of kill assay showed that the percentage of the cells killed increased with increasing concentrations of the fractions, as well as, contact time intervals. Leakages of Protein, Nucleotides and Potassium Ions followed the same trend observed for killing rate. The results suggest that D. edulis leaf fractions induced a bactericidal effect through membrane damage resulting in leakages of cell components caused by the plant extract. Conclusively, this study portends that D. edulis leaf exhibit mode of action by cytoplasmic membrane disruption hence can be used as natural antibacterial agent against disease-causing pathogens like Pseudomonas aeruginosa, Klebsiella pneumoniae, and Staphylococcus aureus.