Analysis of fabrics and metal threads from two Andalusian liturgical vestments from the seventeenth and eighteenth centuries: a multitechnical approach

This manuscript provided one of the first scientific studies performed on ancient Spanish liturgical vestments by using a multitechnical physicochemical approach. The interlining and lining fabrics were done by cotton and the core of threads by silk. Silver, gold and little amounts of copper were detected. The highest values of gold were found in the metal threads of the cope and the gallon of the chasuble. Two layers were identified: the internal composed by silver and the external by silver and gold. The fibers were proved to be degraded and also the surface of the metal, where scratches and silver-based compounds were detected due to environmental and anthropogenic actions. Indigo was employed as dye in the blue and green fabrics. Wax was detected in the yellow fibers, although other dyes could not be discarded. The materials used in the restoration processes were of minor quality.

Viscometric Study of n-Hexylammonium and n-Octylammonium perchlorates in Binary Non-Aqueous Solvents Probed by a Physicochemical Approach in the Temperature Ranging 298 - 328K at Atmospheric Pressure

Viscosity data were measured for n-hexyl ammonium perchlorate (C6H13NH3ClO4)(HAP) and n-octylammonium perchlorate (C8H17NH3ClO4) (OAP) in acetonitrile (AN), dimethylsulfoxide (DMSO) and their binary mixtures containing 0, 20, 40, 60, 80 and 100 mol%DMSO at 298, 308, 318 and 328 K in the concentration range 60-350×10-4 mol.dm-3. The data was further examined to evaluate ion-ion and ion-solvent interactions in terms of the Aand B coefficients of the Jones-Dole equation respectively. A and B coefficients for the studied electrolytes came out be to be positive throughout the whole composition range. However, smaller values of A as compare to B reveal the dominance of ion-solvent interaction over ion-ion interactions especially at 60 mol% DMSO in AN-DMSO mixtures. Thermodynamic parameters like free energy, enthalpy and entropy change of activation of the viscous flow have also been evaluated by using Erying transition state theory.

Reinvigorating Modern Breadmaking Based on Ancient Practices and Plant Ingredients, with Implementation of a Physicochemical Approach

In this study, the potential use of ancient plant ingredients in emerging bakery products based on possible prehistoric and/or ancient practices of grinding and breadmaking was explored. Various ancient grains, nuts and seeds (einkorn wheat, barley, acorn, lentil, poppy seeds, linseed) were ground using prehistoric grinding tool replicas. Barley-based sourdough prepared by multiple back-slopping steps was added to dough made from einkorn alone or mixed with the above ingredients (20% level) or commercial flours alone (common wheat, spelt, barley). Sieving analysis showed that 40% of the einkorn flour particles were >400 μm, whereas commercial barley and common wheat flours were finer. Differential scanning calorimetry revealed that lentil flour exhibited higher melting peak temperature and lower apparent enthalpy of starch gelatinization. Among all bread formulations tested, barley dough exhibited the highest elastic modulus and complex viscosity, as determined by dynamic rheometry; einkorn breads fortified with linseed and barley had the softest and hardest crust, respectively, as indicated by texture analysis; and common wheat gave the highest loaf-specific volume. Barley sourdough inclusion into einkorn dough did not affect the extent of starch retrogradation in the baked product. Generally, incorporation of ancient plant ingredients into contemporary bread formulations seems to be feasible.

Mutanofactin promotes bacterial adhesion and biofilm formation of cariogenic Streptococcus mutans

Cariogenic Streptococcus mutans is known as a predominant etiological agent of dental caries due to its exceptional capacity in forming biofilms. From strains of S. mutans isolated from dental plaque, we here discover a polyketide/non-ribosomal peptide biosynthetic gene cluster, muf, which directly correlates with a strong biofilm-forming capability. We then identify the muf-associated bioactive product, mutanofactin-697 that contains a novel molecular scaffold, along with its biosynthetic logic. Further mode-of-action studies reveal mutanofactin-697 binds to S. mutans cells nonspecifically, increases bacterial hydrophobicity, and promotes bacterial adhesion and subsequent biofilm formation. Our findings provide the first example of a microbial secondary metabolite promoting biofilm formation via a physicochemical approach, highlighting the significance of secondary metabolism in mediating critical processes related to the development of dental caries.