Biosynthesis of Silver Nanoparticles Using Salvia pratensis L. Aerial Part and Root Extracts: Bioactivity, Biocompatibility, and Catalytic Potential.

The aim of this research was the synthesis of silver nanoparticles (SPA- and SPR-AgNPs) using the aqueous extracts of the aerial (SPA) and the root (SPR) parts of the plant Salvia pratensis L., their characterization, reaction condition optimization, and evaluation of their biological and catalytic activity. UV-Vis spectroscopy, X-ray powder diffraction (XRPD), scanning electron microscopy with EDS analysis (SEM/EDS), and dynamic light scattering (DLS) analysis were utilized to characterize the nanoparticles, while Fourier transform infrared (FTIR) spectroscopy was used to detect some functional groups of compounds present in the plant extracts and nanoparticles. The phenolic and flavonoid contents, as well as the antioxidant activity of the extracts, were determined spectrophotometrically. The synthesized nanoparticles showed twice-higher activity in neutralizing 2,2'-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) (ABTS+) compared with the respective extracts. SPR-AgNPs exhibited strong antimicrobial activity against almost all of the tested bacteria (<0.0039 mg/mL) and fungal strains, especially against the genus Penicillium (<0.0391 mg/mL). Moreover, they were fully biocompatible on all the tested eukaryotic cells, while the hemolysis of erythrocytes was not observed at the highest tested concentration of 150 µg/mL. The catalytic activity of nanoparticles toward Congo Red and 4-nitrophenol was also demonstrated. The obtained results confirm the possibility of the safe application of the synthesized nanoparticles in medicine and as a catalyst in various processes.

Analysis of Wild Raspberries (Rubus idaeus L.): Optimization of the Ultrasonic-Assisted Extraction of Phenolics and a New Insight in Phenolics Bioaccessibility.

A simple and efficient ultrasonic-assisted extraction (UAE) technique was developed in order to find optimal conditions for the extraction of total phenolic compounds, flavonoids and anthocyanins in wild raspberry (Rubus idaeus L.) fruits. Several extraction variables, including methanol composition (v/v, %), solid-solvent ratio (g/mL), time (min) and extraction temperature (°C) were optimized using response surface methodology (RSM). Under optimal conditions for extraction, the total phenolics were found in the concentration of 383 mg GAE/100 g of fresh fruit weight, while HPLC-PDA analysis of the optimized extract showed the presence of cyanidin-3-glucoside, cyanidin-3-sophoroside, catechin, gallic and ellagic acid. The experimental values of DPPH and ABTS radical scavenging activities were 29.0 and 39.5 µmol Trolox/g of fresh fruit weight, respectively. In vitro simulated gastrointestinal digestion showed great raspberry phenolics stability. Our study assessed the bioaccessible phenolics in wild raspberry fruits and showed optimal conditions for the effective extraction of bioactive compounds for their analysis.

Application potential of biogenically synthesized silver nanoparticles using Lythrum salicaria L. extracts as pharmaceuticals and catalysts for organic pollutant degradation.

This study was designed to evaluate the optimal conditions for the eco-friendly synthesis of silver nanoparticles (AgNPs) using Lythrum salicaria L. (Lythraceae) aqueous extracts and their potential application and safe use. AgNPs synthesized using L. salicaria aerial parts (LSA-AgNPs) and root extract (LSR-AgNPs) were characterized by UV-Vis spectrophotometry, Fourier transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM/EDS), and X-ray powder diffraction (XRPD). Dynamic light scattering (DLS) was used for the determination of the size distribution profiles of the obtained nanoparticles. Both L. salicaria extracts showed high phenolic content, while the flavone C-glucosides orientin, vitexin, and isovitexin were detected in extracts using HPLC. The synthesized AgNPs displayed growth inhibition of the tested bacteria and fungi in concentrations between 0.156 and 1.25 mg mL-1. The studied nanoparticles also showed antioxidant potential and gained selectivity at different concentrations on different cancer cell lines. Concentrations of LSA-AgNPs were found to be 20.5 and 12 µg mL-1 towards A431 and SVT2, respectively, while LSR-AgNPs were effective only against A431 cancer cells (62 µg mL-1). The hemolytic activity of LSA-AgNPs in concentrations up to 150 µg mL-1 was not observed, while LSR-AgNPs in the highest applied concentration hemolyzed 2.8% of erythrocytes. The degradation possibility of Congo red and 4-nitrophenol using LSA-AgNPs and LSR-AgNPs as catalysts was also proven. The results indicate that L. salicaria may be used for the eco-friendly synthesis of AgNPs with possible applications as antimicrobial and selective cytotoxic agents towards cancer cell lines, as well as in catalytic degradation of pollutants.

Atmospheric Solids Analysis Probe with Mass Spectrometry for Chlorpyrifos and Chlorpyrifos-Oxon Determination in Apples.

Chlorpyrifos (CPS) is a toxic pesticide present in several pesticide formulations, with low degradability by natural processes. The degradation leads to the toxic metabolite chlorpyrifos-oxon (CPO). The analytical techniques used for the CPS and CPO analysis, like UPLC-PDA and GC-MS, are accurate but also expensive and time consuming, and they need sample pretreatment. In the search of a more rapid and simple analytical procedure, atmospheric solids analysis probe with mass spectrometry (ASAP-MS) was optimized for the determination of CPS and CPO in apples (Malus domestica "Idared"). The identification of the analytes was based on protonated ion and isotopic pattern, while the quantification was based on peak intensities. The obtained results were confirmed by re-validated UPLC-PDA and GC-MS techniques. CPS and CPO concentrations determined by ASAP-MS and UPLC-PDA showed moderate discrepancies (on average by 10-20%), thus demonstrating that ASAP-MS can be a semiquantitative tool for the quantification of these compounds. As additional goal of this work, the efficiency of a gamma irradiation treatment to remove CPS and CPO from apples was tested by analyzing their content before and after the irradiation: 89-99% of CPS and CPO were degraded with doses of 3.5-3.8 kGy and 66-72 h of irradiation per sample. Identical degradation results were obtained by UPLC-PDA and ASAP-MS, indicating that the latter technique is well suitable to rapidly check pesticide degradation in apples.