Unearthing the inhibitory potential of phytochemicals from Lawsonia inermis L. and some drugs against dengue virus protein NS1: an in silico approach.

Dengue has received the status of an epidemic and endemic disease, with countless number of infections every year. Due to the unreliability of vaccines and non-specificity of drugs, it becomes necessary to find plant-based alternatives, with less harmful side effects. Lawsonia inermis L., is the sole source of dye, Mehendi. The rich repertoire of phytochemicals makes it useful, medicinally. The main objectives of the study are to explore the anti-dengue properties of the phytochemicals from Lawsonia inermis, and to shortlist potential candidates in curing the disease. Phytochemicals from the plant, and a set of drugs were screened and docked against NS1 protein, a less explored drug target, needed for maintenance of virus life cycle. Ligand screening and docking analysis concluded gallic acid, and chlorogenic acid to be good candidates, exhibiting high binding affinity and extensive interactions with the protein. From among the shortlisted drugs, only Vibegron showed effective binding affinity with NS1 protein with zero violations to the Lipinski's Rule of 5. Molecular dynamic simulations, executed for a time period of 100 nanoseconds, reveal the performance of a ligand within a solvated system. Chlorogenic and gallic acid, formed more stable and compact complexes with protein, with stable energy parameters and strong binding affinity. This was further validated with snapshots taken every 50 nanoseconds, showing no change in binding site between the ligand and protein, within the stipulated time frame. It was interesting to see that, a phenol (chlorogenic acid), served as a better drug candidate, against the NS1 protein.Communicated by Ramaswamy H. Sarma.

Effect of manganese toxicity on pigment content, Hill activity and photosynthetic rate of Vigna radiata L. Wilczek seedlings.

Effect of different concentrations, viz. 10(-4) M, 5 x 10(-4) M, 10(-3) M and 5 x 10(-3) M of manganese sulphate (MnSO4, 7H2O) on chlorophyll, carotenoid pigment content and photosynthesis of mungbean seedlings was examined Progressive increase in manganese sulphate concentration upto 5 x 10(-3) M brought about a progressive decrease in total chlorophyll and chl a content. Chl b content changed very little by excess manganese treatment. Total carotenoid pigment content decreased considerably in comparison to control with every concentration of manganese sulphate tried here. Hill activity of chloroplasts isolated from leaves of mungbean seedling and rate of photosynthesis in terms of CO2 uptake showed progressive reduction along with the increase in concentration of the manganese.