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Sulfonamides, including sulfadoxine (SDX), are widely used antibiotics, particularly for malaria treatment. However, their extensive use has led to environmental pollution, microbial resistance, and public health risks. Advanced Oxidation Processes (AOPs) offer promising methods to degrade such pollutants in water, though they may generate more toxic by-products. This study evaluates three AOPs with different hydroxyl radical generation principles: the Fenton reagent (H2O2/Fe2+), hydrogen peroxide photolysis (UV-C/H2O2), and heterogeneous photocatalysis (UV-A/TiO2). Heterogeneous photocatalysis showed superior performance, achieving 100% degradation and 77% mineralization under optimized conditions. Further analysis explored the effects of UV dose, catalyst concentration, and pH on process efficiency. The influence of water matrices, including Ultrapure Water (UW), Tap Water (TW), and Surface Water (SW) from the Aliakmonas River, was also examined. High-Resolution Mass Spectrometry identified 11 SDX transformation products formed during photocatalysis, with their formation mechanisms reported for the first time. An ecotoxicity assessment using ECOSAR software revealed insights into the potential environmental impact of these by-products.

Effective permeability KP, the ultrafiltration coefficient (KUF), the sieving coefficient (SC), and the loss/permeation of proteins (primarily albumin) are key parameters/specifications characterizing hemofilter (HF) performance. However, there are uncertainties regarding their determination. This work aims (a) to demonstrate that the co-current flow (of blood and dialysate) can lead to beneficial unidirectional filtration (from blood/plasma to dialysate) under a fairly uniform local trans-membrane pressure (TMP), unlike the presently employed counter-current flow; (b) to study the temporal evolution of key HF performance parameters under co-current flow, particularly during the important early stage of hemocatharsis (HC). Experiments with human plasma and BSA solutions in co-current flow mode (for which a fluid mechanical model is developed) show a fairly uniform local/axial TMP, which also improves the local/axial uniformity of protein membrane fouling, particularly under (currently favored) high convective flux operation. Due to incipient membrane fouling, a significant temporal variability/decline in the effective KP is observed, and, in turn, of other parameters (i.e., the Kuf, SC, and permeation/mass flux Mm for albumin and total proteins). A satisfactory correlation of the albumin/protein mass flux Mm with permeability KP is obtained, indicating strong inter-dependence. In conclusion, co-current flow, allowing for a fair local TMP axial uniformity, enables the acquisition of accurate/representative data on the evolution of HF parameters, facilitating their interpretation and correlation. The new results provide a basis for exploring the clinical application of the co-current flow.

Biodiesel is synthesized by the transesterification of triglycerides of oils with short-chain alcohols, such as methanol and ethanol. According to the Renewable Energy Directive guidelines (RED II 2018/2001/EU) the contribution of advanced biofuels, which do not include edible oils, towards the overall EU target, is at 1% in 2025 and at least 3.5% in 2030. Bioprocesses that valorize non-edible oils for the production of second-generation biodiesel could play a critical role in achieving this goal. Immobilized lipases, as well as other enzyme classes, such as cutinases and acyltransferases, are utilized as biocatalysts for this process. For the sustainability of the process, renewable materials can be used as immobilization matrices, or even enzymes anchored on the cells as whole-cell biocatalysts. Membrane reactors can also be employed to facilitate the enzymatic transesterification by conducting a continuous enzymatic reaction and simultaneously separate the products in a single operation. The advances on the aforementioned fast-pacing fields are presented in this work.

This study aims to integrate a novel bio-purification process employing an engineered E. coli strain in the downstream processing of lactic acid (LA) fermentation broths from low-cost renewable biological feedstocks. Fermentation broth of candy waste and digestate mixture was used as a real biological feedstock. An engineered E. coli strain that selectively catabolize impurities without catabolizing LA was initially adapted on the biological feedstock, followed by shake flask experiments to prove the bio-purification concept. Scale-up and validation in a bench-scale bioreactor followed, before developing a semi-continuous membrane bioreactor (MBR) bio-purification process. The MBR bio-purification was assessed with biological feedstocks which simulated ultrafiltration or nanofiltration permeates. Incomplete removal of impurities and increased fouling was observed in the case of the ultrafiltration permeate. Contrarily, the nanofiltration permeate was successfully treated with MBR bio-purification, since low membrane fouling, 100% maltose and acetic acid removal, and no LA catabolism was achieved. MBR bio-purification as a post-treatment step in the downstream processing of LA was demonstrated as a promising technology for increasing the purity of LA solutions.

Reliable mathematical models are important tools for design/optimization of haemo-filtration modules. For a specific module, such a model requires knowledge of fluid- mechanical and mass transfer parameters, which have to be determined through experimental data representative of the usual countercurrent operation. Attempting to determine all these parameters, through measured/external flow-rates and pressures, combined with the inherent inaccuracies of pressure measurements, creates an ill-posed problem (as recently shown). The novel systematic methodology followed herein, demonstrated for Newtonian fluids, involves specially designed experiments, allowing first the independent reliable determination of fluid-mechanical parameters. In this paper, the method is further developed, to determine the complete mass transfer module-characteristics; i.e., the mass transfer problem is modelled/solved, employing the already fully-described flow field. Furthermore, the model is validated using new/detailed experimental data on concentration profiles of a typical solute (urea) in counter-current flow. A single intrinsic-parameter value (i.e., the unknown effective solute-diffusivity in the membrane) satisfactorily fits all data. Significant insights are also obtained regarding the relative contributions of convective and diffusive mass-transfer. This study completes the method for reliable module simulation in Newtonian-liquid flow and provides the basis for extension to plasma/blood haemofiltration, where account should be also taken of oncotic-pressure and membrane-fouling effects.

In this work, novel chrysin-loaded poly(ε-caprolactone) and poly(3-hydroxybutyrate) microcarriers were synthesized according to a modified oil-in-water single emulsion/solvent evaporation method, utilizing poly(vinyl alcohol) surfactant as stabilizer and dispersing agent for the emulsification, and were evaluated for their physico-chemical and morphological properties, loading capacity and entrapment efficiency and in vitro release of their load. The findings suggest that the novel micro-formulations possess a spherical and relatively wrinkled structure with sizes ranging between 2.4 and 24.7 µm and a highly negative surface charge with z-potential values between (−18.1)–(−14.1) mV. The entrapment efficiency of chrysin in the poly(ε-caprolactone) and poly(3-hydroxybutyrate) microcarriers was estimated to be 58.10% and 43.63%, whereas the loading capacity was found to be 3.79% and 15.85%, respectively. The average release percentage of chrysin was estimated to be 23.10% and 18.01%, respectively. The novel micromaterials were further biologically evaluated for their hemolytic activity through hemocompatibility studies over a range of hematological parameters and cytoxicity against the epithelial human breast cancer cell line MDA-MB 231. The poly(ε-caprolactone) and poly(3-hydroxybutyrate) microcarriers reached an IC50 value with an encapsulated chrysin content of 149.19 µM and 312.18 µM, respectively, and showed sufficient blood compatibility displaying significantly low (up to 2%) hemolytic percentages at concentrations between 5 and 500 µg·mL−1.

Sulfonamides, including sulfadoxine (SDX), are widely used antibiotics, particularly for malaria treatment. However, their extensive use has led to environmental pollution, microbial resistance, and public health risks. Advanced Oxidation Processes (AOPs) offer promising methods to degrade such pollutants in water, though they may generate more toxic by-products. This study evaluates three AOPs with different hydroxyl radical generation principles: the Fenton reagent (H2O2/Fe2+), hydrogen peroxide photolysis (UV-C/H2O2), and heterogeneous photocatalysis (UV-A/TiO2). Heterogeneous photocatalysis showed superior performance, achieving 100% degradation and 77% mineralization under optimized conditions. Further analysis explored the effects of UV dose, catalyst concentration, and pH on process efficiency. The influence of water matrices, including Ultrapure Water (UW), Tap Water (TW), and Surface Water (SW) from the Aliakmonas River, was also examined. High-Resolution Mass Spectrometry identified 11 SDX transformation products formed during photocatalysis, with their formation mechanisms reported for the first time. An ecotoxicity assessment using ECOSAR software revealed insights into the potential environmental impact of these by-products. [ABSTRACT FROM AUTHOR]

This study aims to integrate a novel bio-purification process employing an engineered E. coli strain in the downstream processing of lactic acid (LA) fermentation broths from low-cost renewable biological feedstocks. Fermentation broth of candy waste and digestate mixture was used as a real biological feedstock. An engineered E. coli strain that selectively catabolize impurities without catabolizing LA was initially adapted on the biological feedstock, followed by shake flask experiments to prove the bio-purification concept. Scale-up and validation in a bench-scale bioreactor followed, before developing a semi-continuous membrane bioreactor (MBR) bio-purification process. The MBR bio-purification was assessed with biological feedstocks which simulated ultrafiltration or nanofiltration permeates. Incomplete removal of impurities and increased fouling was observed in the case of the ultrafiltration permeate. Contrarily, the nanofiltration permeate was successfully treated with MBR bio-purification, since low membrane fouling, 100% maltose and acetic acid removal, and no LA catabolism was achieved. MBR bio-purification as a post-treatment step in the downstream processing of LA was demonstrated as a promising technology for increasing the purity of LA solutions. [ABSTRACT FROM AUTHOR]

Grapes (Vitis vinifera) are produced in large amounts worldwide and mostly are used for winemaking. Their untreated wastes are rich in valuable secondary metabolites, such as phenolics. Thus, in this study, white and red wine wastes (Malagouzia and Syrah variety) were investigated for their added value phenolics, which were analysed by high performance liquid chromatography (HPLC) and electrospray ionisation-mass spectrometry (ESI/MS) and subsequently encapsulated in several polymers. Extracts from all wastes gave high amounts of total phenolics (13 ± 2.72-22 ± 2.69 mg g−1) and possessed high antioxidant activity (67-97%). In addition to their significant antibacterial activity against gram-negative and gram-positive bacteria, interesting results were also obtained from their anti-inflammatory and antiplatelet activity, in vitro. Encapsulation of the extracts was selective, leaving out most of sugars and other organic compounds when alginate-chitosan was used. Encapsulation efficiency recorded for all extracts ranged from 55% to 79%. Release studies were also performed in several solutions aiming in their commercial use in food and pharmaceutical industries. [ABSTRACT FROM AUTHOR]

In this work, novel chrysin-loaded poly(ε-caprolactone) and poly(3-hydroxybutyrate) microcarriers were synthesized according to a modified oil-in-water single emulsion/solvent evaporation method, utilizing poly(vinyl alcohol) surfactant as stabilizer and dispersing agent for the emulsification, and were evaluated for their physico-chemical and morphological properties, loading capacity and entrapment efficiency and in vitro release of their load. The findings suggest that the novel micro-formulations possess a spherical and relatively wrinkled structure with sizes ranging between 2.4 and 24.7 µm and a highly negative surface charge with z-potential values between (−18.1)–(−14.1) mV. The entrapment efficiency of chrysin in the poly(ε-caprolactone) and poly(3-hydroxybutyrate) microcarriers was estimated to be 58.10% and 43.63%, whereas the loading capacity was found to be 3.79% and 15.85%, respectively. The average release percentage of chrysin was estimated to be 23.10% and 18.01%, respectively. The novel micromaterials were further biologically evaluated for their hemolytic activity through hemocompatibility studies over a range of hematological parameters and cytoxicity against the epithelial human breast cancer cell line MDA-MB 231. The poly(ε-caprolactone) and poly(3-hydroxybutyrate) microcarriers reached an IC50 value with an encapsulated chrysin content of 149.19 µM and 312.18 µM, respectively, and showed sufficient blood compatibility displaying significantly low (up to 2%) hemolytic percentages at concentrations between 5 and 500 µg·mL−1. [ABSTRACT FROM AUTHOR]