Isolation, characterization, antibacterial, antihelminthic, and in silico studies of polyprenol from Kirganelia reticulata Baill

Dehydroabietylamine, A Diterpene from Carthamus tinctorious L. Showing Antibacterial and Anthelmintic Effects with Computational Evidence

BACKGROUND

Plant-based drugs provide an outstanding contribution to modern therapeutics, and it is well known that the presence of different phytochemicals is responsible for such pharmacological effects. Carthamus tinctorius L. is one such medicinally important plant whose different solvent extracts have been reported with several pharmacological effects like antibacterial, hepatoprotective, and wound healing. The exploration of phytoconstituents from such a medicinally important plant for different pharmacological effects could produce new and effective drugs to treat human diseases.

OBJECTIVE

The present study attempts to explore the antibacterial and anthelmintic properties of dehydroabietylamine, a diterpene isolated from Carthamus tinctorius L. followed by the in silico elucidation of its probable mode of action.

METHODS

The minimum inhibition concentration (MIC) and minimum bactericidal concentration (MBC) of dehydroabietylamine were assessed against Staphylococcus aureus and Pseudomonas aeruginosa, using micro- broth dilution method. The anthelmintic activity of was determined to assess the time taken for paralysis and death of Pheretima Posthuma at different concentrations. Additionally, molecular docking study was conducted to understand the interaction between dehydroabietylamine with target proteins identified for both antibacterial and anthelmintic activity viz., glucosamine-6-phosphate synthase and β-Tubulin, respectively.

RESULTS

The dehydroabietylamine showed the significant MIC for S. aureus (12.5 μg/ml) and P. aeruginosa (6.25μg/ml), respectively. The result of anthelmintics effect of dehydroabietylamine was found to be dosedependent and compared to the standard drug, albendazole.

CONCLUSION

The interactions of dehydroabietylamine with the two target proteins with high binding affinity indicated the probable inhibition of target proteins, which could be the cause for prominent antibacterial and antihelminthic effects.

Angular Phenozaxine Ethers as Potent Multi-microbial Targets Inhibitors: Design, Synthesis, and Molecular Docking Studies

The reaction of diaza-5H-benzo[a]phenoxazin-5-one and 5H-benzo[a]phenoxazin-5-one with various phenols catalyzed by Pd/t-BuXPhos/K3PO4 system gave previously unknown ether derivatives (7a-f and 8a-f) in good yields. UV-visible, FTIR, and 1H NMR data were used to confirm structures of the synthesized compounds. The parent compounds and the derivatives were screened in-silico for their drug-likeness and binding affinities to the microbial targets through molecular docking. Molinspiration software and AutoDock were used for the drug-likeness and docking studies, respectively. All the synthesized compounds showed strong drug-likeness. They also showed excellent binding affinities with glucosamine-6-phosphate synthase (2VF5), AmpC beta-lactamase (1KE4), and Lanosterol-14α-demethylase (3JUV), with compound 7e having the highest binding energies -9.5, -9.3, and -9.3 kcal/mol, respectively. These were found to be higher than the binding energies of the standard drugs. The binding energies of ciprofloxacin with 2VF5 and 1KE4 were -7.8 and -7.5 kcal/mol, respectively, while that of ketoconazole with 3JUV was -8.6 kcal/mol. The study showed that the synthesized compounds have multi-target inhibitory effects and can be very useful in multi-drug resistance cases. A 2D quantitative structural activity relationship (QSAR) model against target Glucosamine-6-phosphate synthase (2VF5) was developed using partial least squares regression (PLS) with good internal prediction (R2 = 0.7400) and external prediction (R2_ predicted = 0.5475) via Molecular Operating Environment (2014).

Antibacterial, cytotoxic and genotoxic activity of nitrogenated and haloid derivatives of C50-C60 and C70-C120 polyprenol homologs

Background

Polyprenol is an important lipid with many bioactive effects. The study on differences in bioactive effects of polyprenol derivatives having different isoprene units are seldom reported and it is helpful to find out which type of polyprenol derivatives are effective for treating A549/HepG2 cells and E. coli /S. aureus.

Methods

All tested polyprenol derivatives were measured with inhibition halos by Oxford cup assays. MIC values were assessed by the broth dilution method. Time-killing curve studies were conducted in duplicate on separate days. Cytotoxicity study was measured by the MTT assay and genotoxic study was evaluated by comet assay.

Results

With regard to antibacterial activity, the sensitivities to the quaternary polyprenyl ammonium salt derivatives GAS and MAS were 31.3 μg/mL and 15.6–31.3 μg/mL, respectively. GAS and MAS exhibited cytotoxic activity toward HepG2 cells (IC₅₀ of 10.1–11.6 μg/mL), which was stronger than that exhibited toward A549 cells (IC₅₀ of 13.8–13.9 μg/mL). The bactericidal activity of MAS was stronger than that of GAS at the same concentration at least 48 h. The DNA damage in A549 and HepG2 cells exposed to all 10, 20 and 40 μg/mL MAS was statistically significant in comparison to the control. Our results indicate a dose-dependent increment in DNA damage in A549 and HepG2 cells exposed to 10, 20 and 40 μg/mL MAS for both the percentage of DNA in the tail and tail moment.

Conclusion

The quaternary ammonium salt derivatives GAS and MAS exhibited higher antibacterial (E. coli and S. aureus) and cytotoxic activity (A549 and HepG2 cells) than the other derivatives evaluated in this study. The DNA damage in HepG2 cells suggests that MAS induced A549 and HepG2 cells death via apoptotic pathway. Our results provide new evidence supporting the medical use of polyprenol derivatives against bacterial and tumor diseases.

In vitro and in silico antidiabetic activity of pyran ester derivative isolated from Tragia cannabina

OBJECTIVE

To investigate the in vitro antidiabetic effects of isolated 4-Oxo-4H-pyran-2,6-dicarboxylic acid bis-[6-methyl-heptyl] ester from the chloroform extract of root of Tragia cannabina (T. cannabina) and AMP kinase activation property of the isolated compound.

METHODS

The roots of T. cannabina were collected and extracted with ethanol [95% v/v] then chromatographed over silica gel 60-120 mesh of column length 100 cm and diameter 3 cm. Elution was carried out with solvents and solvent mixtures of increasing polarities. Then the chloroform extract was used for isolation. In vitro antidiabetic activity was performed with fertile eggs of White Leghorn chicks by induction of diabetes by streptozotocin.

RESULTS

The isolated pyran ester binds very efficiently within the active pocket of AMPK with the formation of hydrogen bond and consuming less binding energy, which is good when compared to orientation of standard drug metformin. In in vitro antidiabetic evaluation by streptozotocin treated chick embryo the administration of isolated compound at a doses of 0.5 mg/egg and 1 mg/egg produced a significant reduction in the blood glucose levels in a dose dependant manner (P<0.01). The blood glucose level of diabetic control was (244.20±12.64) mg/dL, whereas it was (207.40±2.43) mg/dL (P<0.001) for isolated compound 0.5 mg/egg and 174.800±2.410 mg/dL (P<0.001) for 1 mg/ egg of the isolated compound.

CONCLUSIONS

The significant glucose levels were reduced (P<0.01) after administration of the pyran ester isolated from T. cannabina to streptozotocin treated chick embryo.