A computational approach to discover antioxidant and anti-inflammatory attributes of silymarin derived from Silybum marianum by comparison with hydroxytyrosol.

Medicinal plants possess therapeutic potential for reducing reactive oxygen species (ROS)-mediated cellular damage. Hydroxytyrosol is one of the most potent antioxidants that served as control in the current study, including other synthetic antioxidants to computationally identify the antioxidant properties of Silymarin. The sequences of the receptors IκB kinase (IKK), Kelch-like ECH-associated protein 1 (Keap-1) and mitochondrial transcription factor A (Tfam) were retrieved from UniProtKB and homology modeling was performed using Swiss-Model server. Thereof the molecular docking and dynamic simulation studies were performed using Schrödinger's software version 11.5. From the current study, it was reported that on comparison of the binding energy of silymarin, hydroxytyrosol, α-tocopherol, ascorbic acid, butylated hydroxy anisole (BHA) and butylated hydroxytoluene (BHT), Silymarin exhibited better affinities with IKK receptor followed by Hydroxytyrosol suggesting it as the best or comparable of all other known antioxidants that could potentially suppress inflammation and other diseases. Also, Silymarin exhibited poorest binding affinity with Tfam promoting mitochondrial biogenesis, thereby scavenging ROS. However, with Keap-1, Silymarin is ranked 4th in the list, whereas hydroxytyrosol exhibited highest binding affinity to release oxidative stress. The stability of docked complexes made us conclude that Silymarin has comparable antioxidant properties to hydroxytyrosol, better anti-inflammatory potential and mitochondrial biogenesis enhancing properties to ultimately reduce oxidative stress. Now it can be tested further for in vitro or in vivo studies as potential drug against oxidative insult.Communicated by Ramaswamy H. Sarma.

Bioactive constituents of Emblica officinalis overcome oxidative stress in mammalian cells by inhibiting hyperoxidation of peroxiredoxins.

Emblica officinalis (Amla) is a renowned fruit having nutritional and medicinal traits mostly linked to its antioxidants content. In the current study, the methanolic crude extract of amla fruit is subjected to sequential fractionation to get its partially purified fractions. The ethyl acetate (EA) and butanol (BUT) fractions of amla showed maximum antioxidant potential. The ferric reducing capability and nitric oxide scavenging activity were highest in EA fraction. One of the highlights of the study is the cellular antioxidant assay conducted in HeLa cells. Additionally, HeLa cells pre-treated with EA and BUT fractions were able to combat oxidative stress via total reduction in hyperoxidation of intracellular peroxiredoxin enzyme. Gallic acid, ascorbic acid, ellagic acid, rutin, quercetin, and catechol are the major compounds present in these fractions as identified by LC-ESI-MS followed by their quantification by HPLC. These findings indicate that components of E. officinalis can protect intracellular oxidative stress-mediated degeneration. PRACTICAL APPLICATIONS: The study highlighted that E. officinalis is a promising source of phenolics and flavonoids acting as natural antioxidants, which showed varied potential to scavenge ROS. Also, the plant fractions were able to fight intracellular oxidative stress via total reduction in hyperoxidation of the human peroxiredoxin. In conclusion, we can say that the regular intake of such food supplements that affect important antioxidant enzymes can be of special interest in the management of oxidative stress-mediated human ailments.

Perspectives on Phytochemicals as Antibacterial Agents: An Outstanding Contribution to Modern Therapeutics.

Despite the considerable advancements in the development of antimicrobial agents, incidents of epidemics due to multi drug resistance in microorganisms have created a massive hazard to mankind. Due to increased resistance against conventional antibiotics, researchers and pharmaceutical industries are more concerned about novel therapeutic agents for the prevention of bacterial infections. Enormous wealth of traditional system of medicine gains importance in health therapies over again. With ancient credentials of potent medicinal plants, various herbal remedies came forward for the management of bacterial infections. The Ayurvedic approach facilitates the development of new therapeutic agents due to structural and functional diversity among phytochemicals. The abundance and diversity is responsible for the characterization of new lead structures from medicinal plants. Industrial interest has increased due to recent research advancements viz. synergistic and high-throughput screening approach for the evaluation of vast variety of phytochemicals. The review certainly emphasizes on the traditional medicines as alternatives to conventional chemotherapeutic drugs. The review briefly describes mode of action of various antibiotics and resistance mechanisms. This review focuses on the chemical diversity and various mechanisms of action of phytochemicals against bacterial pathogens.