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This study focused on describing the bioavailability of ursolic/oleanolic acids (UA/OA) and the methods to increase it, so that these 2 bioactive compounds can have therapeutic and preventive effects in chronic diseases and cancer. Ursolic/oleanolic acids are natural compounds that have been known since the 19th century. They are very widespread and offer special benefits for human health - especially that their high absorbability makes them suitable for use in therapeutic and preventive treatment. One of the important aspects of their bioavailability is related to their interaction with other bioactive compounds or drugs. In chronic diseases and cancer, UA/OA may affect the absorption of other nutrients and interact with bioactive compounds. By increasing the bioavailability of UA/OA with various technical processes, especially using nanocarriers and nanoparticles, these compounds can affect collagen production, contributing to maintaining skin elasticity and preventing the appearance of wrinkles. Today, UA/OA are frequently used to treat many conditions, ranging from chronic to metabolic.

Ca- and Cu-decorated TiO 2 microparticles are titanium dioxide nanoparticles that have been decorated with calcium and copper ions. TiO 2 , CaO, and CuO are low-cost, non-toxic, and non-hazardous materials. The aim of the present study was the physicochemical characterization of Ca- and Cu-decorated TiO 2 microparticles and the evaluation of their antimicrobial activity. Thus, Ca 2+ and Cu 2+ species were incorporated onto TiO 2 surfaces by a two-step wet method. The obtained TiO 2 -CaO-CuO composites were characterized by several experimental techniques. The electronic structure and charge properties of the composites were investigated by density functional theory calculations. Furthermore, the composites were successfully tested for inhibitory effects on Staphylococcus aureus , Pseudomonas aeruginosa , Escherichia coli , and Candida albicans standard strains. The zeta potential data indicate that the physiological condition of investigated microbial strains was strongly affected in presence of a dispersion of 10 μg/L of composites in a saline phosphate buffer also, the recorded SEM images show a damaged microbial cell surface in the presence of composites.

Hedera helix L. contains phytochemicals with good biological properties which are beneficial to human health and can be used to protect plants against different diseases. The aim of this research was to find the most suitable extraction method and the most favorable parameters for the extraction of different bioactive compounds from ivy leaves. Different extraction methods, namely microwave-assisted extraction (MAE), ultrasound-assisted extraction (UAE), and conventional heating extraction (CHE), were used. The most suitable method for the extraction of saponins is MAE with an extraction efficiency of 58%, while for carbohydrates and polyphenols, the best results were achieved via UAE with an extraction efficiency of 61.7% and 63.5%, respectively. The antioxidant activity (AA) of the extracts was also determined. The highest AA was obtained via UAE (368.98 ± 9.01 µmol TR/gDM). Better results were achieved at 50 °C for 10 min of extraction, using 80% ethanol in water as solvent. In order to evaluate their in vitro cytotoxicity, the extracts richest in bioactive compounds were tested on NCTC fibroblasts. Their influence on the DNA content of RAW 264.7 murine macrophages was also tested. Until 200 µg/mL, the extracts obtained via UAE and MAE were cytocompatible with NCTC fibroblasts at 48 h of treatment. Summarizing the above, both MAE and UAE can be employed as green and efficient methods for producing extracts rich in bioactive compounds, exhibiting strong antioxidant properties and good noncytotoxic activity.

The influence of ultrasound irradiation on the algal biomass productivity as well as its oil content and fatty acids profile, grown in a modified Zarrouk medium, i.e., deproteinized whey waste solution, was investigated. The algal samples ( Nannochloris sp. 424-1 microalgae) were grown for 7 days in a thermostated incubator at 28 °C, shaken under continuous light. During this period, the algal biomass was subjected to induced stress by ultrasonic irradiation at different powers and sonication time. The obtained results demonstrate that ultrasound stressing of algae biomass has a positive effect on both the quantity of biomass and the oil obtained, also causing a shift in fatty acid composition by increasing the proportion of C16 and C18 polyunsaturated fatty acids. A low dosage level of exposure to the ultrasound led to algal biomass increase as well as lipid accumulation. For both types of irradiation modes which were investigated, daily and only initial irradiation, the beneficial effect of the ultrasound decreases as the exposure time increases and the excessive sonication becomes detrimental to microalgae growth.

The aim of this study was to establish the best ultrasound assisted extraction (UAE) conditions of saponins from Hedera helix L. leaves and to evaluate the in vitro biocompatibility of the extracts richest in saponins. Different parameters, such as extraction time, temperature, ultrasound power, solvent to plant material ratio, and solvent concentration, were investigated. The most efficient extraction conditions were a temperature of 50 °C, an ultrasound amplitude of 40%, an extraction time of 60 min, a plant material to solvent ratio of 1:20 (w:v), and 80% ethanol as solvent. In vitro cytotoxicity of the extracts richest in saponins and their influence on the DNA content of L929 (NCTC) fibroblasts were tested. Until 200 µg/mL, the studied extracts were cytocompatible with L929 fibroblast cell lines at 48 h of treatment. These in vitro cell culture results provide useful information for further applications of Hedera helix extracts in a pharmaceutical field.

This work is focused on the study of the esterification parameters for the ultrasound assisted synthesis of isoamyl acetate catalyzed by lipase Lipozyme 435 in a continuous loop reactor. Investigating the influence of different parameters shows that a higher concentration of ester (462 mg/g mixture) can be obtained at a temperature of 50 °C, flow rate 0.16 mL/min. The best ultrasonication conditions are: sonication applied continuously for a short time (20 min), ultrasound power 32 mW and amplitude 20%. The enzyme can be successfully reused tree times without loss of enzyme activity. Reaction kinetics for isoamyl acetate ultrasound assisted production showed that satisfactory reaction concentration (close to the equilibrium concentrations) could be reached in short reaction times (2 h). Ultrasound assisted enzymatic esterification is consequently a cleaner and a faster process., (© 2022. The Author(s).)

Preventing and controlling the spread of multidrug-resistant (MDR) bacteria implicated in healthcare-associated infections is the greatest challenge of the health systems. In recent decades, research has shown the need for passive antibacterial protection of surfaces in order to reduce the microbial load and microbial biofilm development, frequently associated with transmission of infections. The aim of the present study is to analyze the efficiency of photocatalytic antimicrobial protection methods of surfaces using the new photocatalytic paint activated by light in the visible spectrum. The new composition is characterized by a wide range of analytical methods, such as UV-VIS spectroscopy, electron microscopy (SEM), X-ray powder diffraction (PXRD) or X-ray photoelectron spectroscopy (XPS). The photocatalytic activity in the UV-A was compared with the one in the visible light spectrum using an internal method developed on the basis of DIN 52980: 2008-10 standard and ISO 10678-2010 standard. Migration of metal ions in the composition was tested based on SR EN1186-3: 2003 standard. The new photocatalytic antimicrobial method uses a type of photocatalytic paint that is active in the visible spectral range and generates reactive oxygen species with inhibitory effect against all tested microbial strains.

At this time biodiesel appears to be a viable proposition as a renewable energy source and an alternative to fossil-based fuels. Following many years of research, the use of process intensification techniques for the production of biodiesel is well documented. This work has focused more on a study of biodiesel production using continuous flow systems assisted by acoustic cavitation (ultrasonic or hydrodynamic) or microwaves. The target end user is the small or medium farm where such equipment could provide sufficient fuel for on-site agricultural machinery using renewable or waste green materials produced on site., (Copyright © 2019 Elsevier B.V. All rights reserved.)

Sea buckthorn (Hippophae Rhamnoides L.) is an important source of bioactive compounds such as: antioxidants, vitamins, fatty acids, amino acids, and minerals. Sea buckthorn leaves extracts have been proved to have anti-microbial, antioxidant, anti-inflammatory, and anti-viral properties. In this paper, the extraction of polyphenols from sea buckthorn leaves using a semi-continuous small-scale reactor is described. The extraction conditions must not affect the composition and structure of polyphenols. For this reason, the influence of different parameters (residence time, solvent flow rate, stirring rate, reactor type, and solvent pre-heating) on the extraction process were studied. The polyphenolic extracts were analyzed in order to determine the total phenolic content (TPC), the antioxidant capacity and the concentration of the main phenolic compounds. The TPC increases with the stirring rate. Pre-heating the solvent leads to a better yield and reduced residence time. The antioxidant capacity is in concordance with the TPC results. HPLC analysis confirms that the semi-continuous microwave assisted extraction (MAE) does not affect the composition of the extracts. The energy consumption was significantly lower for MAE compared with conventional extraction (CE).

This work presents a method and a semi-pilot scale installation (SPSI) for the simultaneous SO2 and NOx removal by separate and combined microwave (MW) and electron beam (EB) irradiation. The SPSI consists mainly of the following units: a gaseous mixture preparation system (GMPS), a microwave source (MS) of 2.45 GHz and 4.2 kW maximum output power an electron beam source (EBS) of 1.8 MeVand 10.8 kW maximum output power and a multimode rectangular cavity (MRC), used as reaction chamber in which are injected both MW and EB fields. The most important parameters for high SO2 removal efficiencies obtained by MW technology are water and ammonia concentration, the gaseous mixture temperature during irradiation process and MW power level. The most important parameter for high NOx removal efficiency obtained by MW technology is MW power level. The removal efficiencies obtained by MW processing were up to 95% for SO2 and up to 55% for NOx. The additional use of EB irradiation to MW exposure strongly increases NOx removal efficiencies in comparison with MW exposure only, up to 95%, simultaneously providing very high values for the SO2 removal efficiency, near 100%.

This work presents a hybrid technology and two hybrid installations (HI-1 and HI-2) for volatile organic compounds (VOCs) removal using successive or simultaneous microwave (MW) irradiation, electron beam (EB) irradiation, and catalytic oxidation. HI-1 is designed for successive EB and MW irradiation with two distinct reactors, both containing a catalyst inside. HI-2 is designed for simultaneous EB and MW irradiation in the same reactor containing a catalyst. Real synergistic effects between non-thermal plasma (NTP) and catalysis were obtained by introducing the catalyst into the irradiation zone, i.e. into the MW reactor EB reactor or into a reactor in which both EB and MW are injected.

Liquid-phase polymerisation of acrylamide-acrylic acid to form polyelectrolytes used in wastewater cleaning was examined using accelerated electron beam and microwave irradiation methods. Polymerisation was carried out in aqueous solutions at temperatures approximately 60 degrees C. Monomers total concentration was established at 40% (36% acrylamide and 4% acrylic acid). Only using the features of simultaneous radiation-induction and microwave heating can result in the formation of linear polymer chains with good water solubility and low residual monomer concentration. The flocculation capacity of the obtained polymers was tested using two wastewaters, one sampled from a slaughterhouse and the other from a vegetable oil plant. Quality indicators such as total suspended matters (TSM), chemical oxygen demand (COD), biological oxygen demand (BOD) and fat, oils and grease (FOG) were measured before and after the treatment with polymeric flocculants and compared with the results obtained in classical treatment with Al(2)(SO(4))(3). It was found that the combined treatment with polymers and Al(2)(SO(4))(3) increases the degree of purification of both wastewaters up to 99%.

Microwave discharges at 2.45 GHz frequency and accelerated electron beams operated at atmospheric pressure in synthetic gas mixtures containing N(2), O(2), CO(2), SO(2), and NO(x) are investigated experimentally for various gas mixture constituents and operating conditions, with respect to their ability to purify exhaust gases. An original experimental unit easily adaptable for both separate and simultaneous irradiation with microwaves and electron beams was set up. The simultaneous treatment with accelerated electron beams and microwaves was found to increase the removal efficiency of NO(x) and SO(2) and also helped to reduce the total required dose rate with approximately 30%. Concomitant removal of NO(x) ( approximately 80%) and SO(2) (>95%) by precipitation with ammonia was achieved.