Scale-up of Aflatoxin Purification by Centrifugal Partition Chromatography.

Aflatoxins (AFs) are a group of secondary metabolites that cause several diseases in both animals and humans. Since the discovery of this group of toxins, several effects were revealed, such as hepatic changes, carcinoma, failure, and cancer of the liver. In the European Union, there are concentration limits for this group of mycotoxins in food and feed products; thus, these substances are required in their pure forms to prepare reference standards or certified reference materials.

Corrigendum: Structural Diversity and Bioactivities of Peptaibol Compounds From the Longibrachiatum Clade of the Filamentous Fungal Genus .

[This corrects the article DOI: 10.3389/fmicb.2019.

Stereoselective synthesis and application of isopulegol-based bi- and trifunctional chiral compounds.

A new family of isopulegol-based bi- and trifunctional chiral ligands was developed from commercially available (-)-isopulegol. Nucleophilic addition of primary amines towards (+)-α-methylene-γ-butyrolactone was accomplished, followed by reduction of the obtained β-aminolactones to provide aminodiols in highly stereoselective reactions. Epoxidation of (-)-isopulegol and subsequent oxirane ring opening with primary amines resulted in -substituted aminodiols.

Structural Diversity and Bioactivities of Peptaibol Compounds From the Longibrachiatum Clade of the Filamentous Fungal Genus .

This study examined the structural diversity and bioactivity of peptaibol compounds produced by species from the phylogenetically separated Longibrachiatum Clade of the filamentous fungal genus , which contains several biotechnologically, agriculturally and clinically important species. HPLC-ESI-MS investigations of crude extracts from 17 species of the Longibrachiatum Clade (. , and ) revealed several new and recurrent 20-residue peptaibols related to trichobrachins, paracelsins, suzukacillins, saturnisporins, trichoaureocins, trichocellins, longibrachins, hyporientalins, trichokonins, trilongins, metanicins, trichosporins, gliodeliquescins, alamethicins and hypophellins, as well as eight 19-residue sequences from a new subfamily of peptaibols named brevicelsins.

Separation and Purification of Aflatoxins by Centrifugal Partition Chromatography.

Aflatoxins are mycotoxins that are produced by several species of filamentous fungi. In the European Union, the concentration limits for this group of mycotoxins in food and feed products are very low (on the order of parts per billion). Thus, relatively high amounts of these substances in their pure forms are required as reference standards.

The evaluation of 5-amino- and 5-hydroxyuracil derivatives as potential quadruplex-forming agents.

5-Substituted uracils (NH or OH groups in position 5) have been examined theoretically and experimentally as potential building blocks in quadruplex structures. Our high level Density Functional Theory (DFT) calculations showed that the tetramer formation and stacking energies for 5-substituted uracils are similar to the energies of purine-based xanthine (X) or guanine (G) structures. As tetrads of 5-substituted uracils cover almost exactly the same area as purine tetrads, mixed tetrads or quadruplex structures based on X or G and 5-substituted uracil motifs are possible.