Simultaneously Determined Antioxidant and Pro-Oxidant Activity of Randomly Selected Plant Secondary Metabolites and Plant Extracts.

Oxidative stress is a well-known phenomenon arising from physiological and nonphysiological factors, defined by the balance between antioxidants and pro-oxidants. While the presence and uptake of antioxidants are crucial, the pro-oxidant effects have not received sufficient research attention. Several methods for assessing pro-oxidant activity, utilizing various mechanisms, have been published. In this paper, we introduce a methodology for the simultaneous determination of antioxidant and pro-oxidant activity on a single microplate in situ, assuming that the FRAP method can measure both antioxidant and pro-oxidant activity due to the generation of pro-oxidant Fe2+ ions in the Fenton reaction. Systematic research using this rapid screening method may help to distinguish between compounds with dominant antioxidant efficacy and those with dominant pro-oxidant effects. Our preliminary study has revealed a dominant pro-oxidant effect for compounds with a higher number of oxygen heteroatoms, especially sp2 hybridized compounds (such as those containing keto groups), such as flavonoids and plant extracts rich in these structural types. Conversely, catechins, carotenoids, and surprisingly, extracts from birch leaves and chestnut leaves have demonstrated dominant antioxidant activity over pro-oxidant. These initial findings have sparked significant interest in the systematic evaluation of a more extensive collection of compounds and plant extracts using the developed method.

The Adapted POM Analysis of Avenanthramides In Silico.

POM analysis and related approaches are significant tools based on calculating various physico-chemical properties and predicting biological activity, ADME parameters, and toxicity of a molecule. These methods are used to evaluate a molecule's potential to become a drug candidate. Avenanthramides (AVNs) are promising secondary metabolites specific to Avena spp. (oat). They comprise the amides of anthranilic acid linked to various polyphenolic acids with or without post-condensation molecule transformation. These natural compounds have been reported to exert numerous biological effects, including antioxidant, anti-inflammatory, hepatoprotective, antiatherogenic, and antiproliferative properties. To date, almost 50 various AVNs have been identified. We performed a modified POM analysis of 42 AVNs using MOLINSPIRATION, SWISSADME, and OSIRIS software. The evaluation of primary in silico parameters revealed significant differences among individual AVNs, highlighting the most promising candidates. These preliminary results may help coordinate and initiate other research projects focused on particular AVNs, especially those with predicted bioactivity, low toxicity, optimal ADME parameters, and promising perspectives.

Ethanol and NaCl-Induced Gold Nanoparticle Aggregation Toxicity toward DNA Investigated with a DNA/GCE Biosensor.

Engineered nanomaterials are becoming increasingly common in commercial and consumer products and pose a serious toxicological threat. Exposure of human organisms to nanomaterials can occur by inhalation, oral intake, or dermal transport. Together with the consumption of alcohol in the physiological environment of the body containing NaCl, this has raised concerns about the potentially harmful effects of ingested nanomaterials on human health. Although gold nanoparticles (AuNPs) exhibit great potential for various biomedical applications, there is some inconsistency in the case of the unambiguous genotoxicity of AuNPs due to differences in their shape, size, solubility, and exposure time. A DNA/GCE (DNA/glassy carbon electrode) biosensor was used to study ethanol (EtOH) and NaCl-induced gold nanoparticle aggregation genotoxicity under UV light in this study. The genotoxic effect of dispersed and aggregated negatively charged gold nanoparticles AuNP1 (8 nm) and AuNP2 (30 nm) toward salmon sperm double-stranded dsDNA was monitored by cyclic and square-wave voltammetry (CV, SWV). Electrochemical impedance spectroscopy (EIS) was used for a surface study of the biosensor. The aggregation of AuNPs was monitored by UV-vis spectroscopy. AuNP1 aggregates formed by 30% v/v EtOH and 0.15 mol·L-1 NaCl caused the greatest damage to the biosensor DNA layer.