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This work aimed to investigate the optimum conditions of pressure, temperature, ultrasound intensity, solvent concentration and solvent flowrate of ultrasound-assisted pressurized liquid extraction of anthocyanins from Aronia melanocarpa pomace. The novel setup operates with an aqueous solution of citric acid as extraction solvent. The optimization was performed in order to maximize the total anthocyanins content extracted from the pomace. The optimized conditions of 70 °C, 180 bar, a solvent concentration of 1.5 % wt. citric acid, in a 200 W ultrasound bath were obtained. These conditions resulted in 88.0 % wt. extraction of anthocyanins in 45 min. A kinetic study was performed to study the influence of the temperature on the total anthocyanin yield obtained at the optimal extraction conditions. Moreover, the component stability was assessed to prove that the system could successfully operate at 80 °C. Compared to classical batch extraction using the same solvent concentration and feedstock, the total anthocyanin content of the extract was increased by 19%.

Phycocyanins from cyanobacteria are possible sources for new natural blue colourants. Their chromophore, phycocyanobilin (PCB), was cleaved from the apoprotein by solvolysis in alcohols and alcoholic aqueous solutions. In all cases two PCB isomers were obtained, while different solvent adducts were formed upon the use of different reagents. The reaction is believed to take place via two competing pathways, a concerted E2 elimination and a S N2 nucleophilic substitution. Three cleavage methods were compared in terms of yield and purity: conventional reflux, sealed vessel heated in an oil bath, and microwave assisted reaction. The sealed vessel method is a new approach for fast cleavage of PCB from phycocyanin and gave at 120 °C the same yield within 30 min compared to 16 h by the conventional reflux method (P

The production of sour cherry wine results in large amounts of biowaste known as press cake or pomace. This pomace contains among others the fruit skin and flesh that have been previously reported to be a rich source of anthocyanins and phenolic acids. These components can be extracted and formulated to be used as natural pigments, nutraceuticals or cosmeceuticals. In the present work, sour cherry wine pomace has been extracted in aqueous buffers and ultrafiltered using ceramic membranes. Two enzyme formulations based on pectinases and cellulases have been added to the extraction media, and their influence on the extraction yield in batch mode, ultrafiltration performance and product degradation has been assessed. Sour cherry wine pomace has been found to contain relatively low amounts of anthocyanins (48.6 ± 0.9 mg kg-1) and phenolic acids (82.1 ± 2.9 mg kg-1) as compared to biowaste from other sour cherry food products. The use of enzyme formulations based on cellulase and pectinase was not shown to improve the total amount of anthocyanin and phenolic acids extracted. However, an increase in ultrafiltration permeate flux was observed when the enzymes were used.

The mechanism of the salt-to-free form drug transformation was explored by investigating the pH-solubility profiles of a model drug in a salt form and the nucleation of the free base from the salt solution when its pH was increasing. The transformation of the salt to the free base during wet massing in the presence of pharmaceutical excipients with different pH was studied. The nucleation of the free base occurred when the pH of the salt solution reached a certain level pHmetastable, which was related to the free energy penalty associated with the creation of a new solid phase. The nucleation of the free base happened readily and thus, the salt-to-free base transformation occurred rapidly during wet massing with the excipients with a pH above the pHmetastable. These results can support robust formulation design of solid dosage forms containing salts by optimal excipient selection.