Phytochemical Screening of Ultrasonic Extracts of Salix Species and Molecular Docking Study of Salix-Derived Bioactive Compounds Targeting Pro-Inflammatory Cytokines.

Willow bark (Salix spp., Salicaceae) is a traditional analgesic and antirheumatic herbal medicine. The aim of this study was to evaluate and compare the phytochemical and antioxidant profiles of leaf and bark extracts of six species of the genus Salix obtained by ultrasound-assisted extraction (UAE) and to examine the inhibitory potential of target bioactive compounds against two inflammatory mediators, tumor necrosis factor alpha (TNF-α) and interleukin 6 (IL-6), through in silico molecular docking. The total phenolic and flavonoid content of the extracts was estimated using spectrophotometric methods and the antioxidant activity using 2,2-diphenyl-1-picrylhydrazyl (DPPH•) and hydroxyl radical (•OH) scavenging assays. Chemical profiling of extracts was carried out using high-performance liquid chromatography coupled with a diode array detector (HPLC-DAD). Principal component analysis (PCA) was performed to differentiate the sample extracts based on their phytochemical profiles and amounts of target bioactive compounds. Chemical composition varied among the analyzed willow species and also among the plant organs of the same species. The major bioactive compounds of the extracts were salicin, chlorogenic acid, rutin and epicatechin. The extracts exhibited significant DPPH● and ●OH scavenging activities. Results of molecular docking revealed that chlorogenic acid had the highest binding affinity toward TNF-α and IL-6. UAE extracts represent valuable sources of antioxidant and anti-inflammatory compounds.

Ibuprofen as an Organic Pollutant in the Danube and Effects on Aquatic Organisms.

The presence of emerging substances in surface water is of a great concern knowing they are the main source for community water supply needs. This study describes the development, optimization and application of an analytical method for the determination of ibuprofen in the Danube samples. Caffeine concentrations, as an indicator of human waste, were determined and maximum risk indexes for aquatic organisms were calculated. The Danube samples were collected from ten representative locations. A Solid-phase extraction was used for ibuprofen and caffeine separation and the analysis was performed by High-performance liquid chromatography method. Ibuprofen concentrations ranged (30.62-111.40) ng/L and caffeine (305.94-375.97) ng/L. Low risk on aquatic organisms was determined for ibuprofen and potential sublethal effect for caffeine was obtained. The results indicated that ibuprofen was effectively separated from other substances in the samples under defined chromatographic conditions for short period of time (4 minutes). Applied HPLC method showed good repeatability, accuracy, selectivity and robustness. Further studies including continuous monitoring of caffeine in the Danube are necessary in order to assess the real risks and possible prevention.

Experimental and Computational Evaluation of Extraction Procedure and Scavenging Capacity of Sweet Basil Extracts (Ocimum basilicum L.).

The possibility to prevent nutrition-related diseases that include scavenge of free radicals and to block chain reactions is very important and significant for human well-being. The aim of this study was to analyse different basil extracts, determine the relationship between total phenolic/flavonoid content and antioxidant activity in order to optimize its application in industry. The extraction involved different solvents (ethanol, methanol and water), extraction time (10 and 30 min and 24, 48 and 72 h), plant fragmentation level (0.3 and 2 mm) and the presence or absence of light. Antioxidant activity was investigated by applying spectrophotometric method and measuring the total phenolic and flavonoid content and DPPH radical scavenging activity. The content of total phenolics varied from 5.2 to 185.6 mg of gallic acid equivalents per gram of a dry extract and flavonoids ranged from 0.2 to 35.0 mg of quercetin per gram of a dry extract. All extracts presented a scavenging capacity and IC50 values of DPPH radical inhibition ranged from 0.04 to 12.99 µg/ml. The evaluation of experimental data for eighty basil extracts was performed by chemometric analysis showing good correlation between yield and total phenolic compounds, as well as flavonoid content and inhibition of the DPPH radical.

Methodological Aspects of Extraction, Phytochemical Characterization and Molecular Docking Studies of Salix caprea L. Bark and Leaves.

Contents of twelve selected bioactive substances and antioxidant potential of Salix caprea L. extracts were compared in its two vegetative organs (bark and leaves) and in terms of different ethanol/water mixtures used for extraction (30-70% aq, ethanol) and extraction time (30 min; 24, 48 and 72 h). The extracts were characterized by High Pressure Liquid Chromatography (HPLC), and total phenolics and flavonoids were determined spectrophotometrically. All secondary metabolites identified in Salix caprea L. extracts (gallic, chlorogenic and vanillic acid, epicatechin, rutin, quercetin and naringenin) were found more accumulated in bark. Salicin and p-hydroxybenzoic acid were detected in bark and ferulic, trans-cinnamic and p-coumaric acid in leaves extracts only. Rutin was most abundant bioactive compound both in bark (1.71 g/100 g of de) and leaves extracts (0.434 g/100 g of de). Bark extract with highest bioactive substances contents was obtained with 70% aq. ethanol as most suitable solvent during extraction time of 48 h. Molecular docking showed salicin to have similar affinity toward COX-2 as acetylsalicylic acid, but lower toward COX-1.