Potential for fungal dyes as colorants in oil and acrylic paints

Potential applications for colorants derived from the spalting fungi Chlorociboria aeruginascens, Chlorociboria aeruginosa, Scytalidium cuboideum, and Scytalidium ganodermophthorum are of growing interest across a variety of fields, from wood and textile dyes, to solar cells. Previous research found that these dyes could be carried in natural oils, specifically raw linseed oil, instead of organic solvents, thereby eliminating the toxicity issues surrounding such carriers. In this work, dyes from the aforementioned fungi were extracted, carried in raw linseed oil, and mixed with a range of oil and acrylic paints to determine if the oil carrier was appropriate for delivering the dyes into a paint matrix. The oil-based dyes did not mix evenly with the acrylic paints; however, the acrylic paints maintained the color of the dyes. In contrast, the oil-based paints mixed well with the dyes, but the dyes decolorized (completely lost color) due to the presence of refined linseed oil in the paint base. Artists’ paints do not appear to be compatible with fungal dyes when carried in oil; however, there are still many potential applications for the oil-based dyes, such as wood and textile dyeing.     

Substituenteneinfluß auf die T1- Energie und auf S1-T1-Energiegap bei ω-Phosphor-substituierten trans-Styrenen

Influence of Substituents on the T₁ Energy and the S₁-T₁ Energy Gap in ω-Phosphorus Substituted trans-Styrenes The fluorescence and the phosphorescence of 4-substituted ω-diphenylphosphinyl trans-styrenes 1 and analogous diphenylthiophosphinyl trans-styrenes 2 at 77 K indicate together with some oxygen-induced singlet-triplet absorption spectra a bathochromic shift of the lowest singlet (S₁) and the lowest triplet level (T₁) relatively to the S₁ and T₁ level of the unsubstituted compounds 1a and 2a , respectively. Donor substituents X in 4-position give rise to a shift of S₁, which is in the most cases much greater than that of T₁, so that the S₁–T₁ energy gap decreases. P(Y)R¹R² groups (Y = O, S) in ω-position of 1 and 2 effect a small bathochromic shift of the T₁ energy level only (130–900 cm⁻¹ relatively to unsubstituted styrene). S₁ is shifted 860–2080 cm⁻¹ to lower energies, however.     

Analysis of 5-hydroxymethylfurfual in coffee, dried fruits and urine

5-Hydroxymethylfurfural has become a substance of interest since recent results showed a possible carcinogenic potential in consequence of a metabolic activation by sulfotransferases. 5-Hydroxymethylfurfural is formed either by acid catalysed degradation of reducing sugars or via the Maillard reaction. This work provides an overview of foods potentially containing high amounts of 5-hydroxymethylfurfural. It comprises dried fruits with a high sugar content that were exposed to heat for a long time. The concentration ranges from very low in, e. g. figs (1 mg/kg) to plums that contained up to 2,200 mg/kg. Several types of roasted coffee were analysed that contained from 300 to 2,900 mg/kg of 5-hydroxymethylfurfural. In a small human study with seven healthy volunteers the urine excretion of unmetabolised 5-hydroxymethylfurfural was investigated. After uptake of 20 g of plum jam containing 24 mg of 5-hydroxymethylfurfural, 163 microg (mean) were excreted within 6 h, an equivalent of 0.75% of the ingested 5-hydroxymethylfurfural.