Production of verbascoside and phenolic acids in biomass of <i>Verbena officinalis</i> L. (vervain) cultured under different <i>in vitro</i> conditions

<p>Methanolic extracts from the biomass of <i>Verbena officinalis</i> cultured under continuous artificial light and in darkness on 12 variants of the Murashige and Skoog medium containing different concentrations (0.5–3.0 mg/L) of plant growth regulators: 6-benzyladenine, kinetin, 1-naphthaleneacetic acid and indole-3-butyric acid, were analysed for the amounts of verbascoside and phenolic acids, before and after acid hydrolysis, using the HPLC-DAD method. The amounts of verbascoside were very high (max. 2454.12 mg/100 g DW – light, and 2135.59 mg/100 g DW – darkness). The total amounts of phenolic acids reached a maximum of 46.02 mg/100 g DW (free phenolic acids) and 141.05 mg/100 g DW (bound compounds). The main metabolites were: ferulic, o-coumaric and caffeic acids. The maximum amount of verbascoside was 3.28 times higher than in extracts from the herb of the parent plant. The cultures could be proposed as a potential biotechnological source for selected biologically active compounds.</p

Data from: Intramolecular transformation of an antifungal antibiotic nystatin A1 into its isomer, iso-nystatin A1. Structural and molecular modeling studies

Nystatin A₁, a polyene macrolide antifungal antibiotic, in a slightly basic or acidic solution undergoes an intramolecular transformation, yielding a structural isomer, the translactonisation product, <i>iso</i>-nystatin A₁ with lactone ring diminished by two carbon atoms. Structural evidence is provided by advanced NMR and MS studies. Molecular dynamics simulations and quantum mechanics calculations gave the insight into the course and mechanism of the transformation and its effect on the conformation of the subject molecule.<br