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The emergence of antimicrobial resistance due to antibiotics in the environment presents significant public health, economic, and societal risks. This study addresses the need for effective strategies to reduce antibiotic residues, focusing on ciprofloxacin degradation. Magnetic iron oxide nanoparticles (IO NPs), approximately 13 nm in size, were synthesized and functionalized with branched polyethyleneimine (bPEI) to obtain a positive charge. These IO-bPEI NPs were combined with negatively charged titanium dioxide NPs (TiO2@CA) to form magnetically photocatalytic IO-TiO2 nanocomposites. Characterization techniques, including X-ray diffraction (XRD), transmission electron microscopy (TEM), scanning electron microscopy (SEM), infrared spectroscopy (IR), X-ray photoelectron spectroscopy (XPS), thermogravimetric analysis (TGA), electrokinetic measurements, and a vibrating sample magnetometer (VSM), confirmed the successful formation and properties of the nanocomposites. The nanocomposites exhibited a high specific surface area, reduced mobility of photogenerated charge carriers, and enhanced photocatalytic properties. Testing the photocatalytic potential of IO-TiO2 with ciprofloxacin in water under UV-B light achieved up to 70% degradation in 150 min, with a degradation rate of 0.0063 min−1. The nanocomposite was magnetically removed after photocatalysis and successfully regenerated for reuse. These findings highlight the potential of IO-TiO2 nanocomposites for reducing ciprofloxacin levels in wastewater, helping curb antibiotic resistance.

Microemulsions, which are thermodynamically stable and isotropic mixtures of water, oil, and surfactants, attract significant research interest due to their unique physicochemical properties and diverse industrial applications. Traditional surfactant-based microemulsions (SBMEs) stabilize the interface between two typically immiscible liquids, forming various microstructures such as oil-in-water (O/W) droplets, water-in-oil (W/O) droplets, and bicontinuous phases. However, the use of surfactants poses environmental concerns, cost implications, and potential toxicity. Consequently, there is increasing interest in developing surfactant-free microemulsions (SFMEs) that offer similar benefits without the drawbacks associated with surfactants. In this study, we explore the formation and characteristics of a new surfactant-free microemulsion in a ternary system comprising water, ethanol, and heptanol. Advanced techniques are employed to characterize the microstructures and stability of surfactant-free microemulsions. These include electrical conductivity measurements, surface tension analysis, dynamic light scattering (DLS), and Fourier transform infrared spectroscopy (FTIR). These methods have been extensively used in previous research on surfactant-free microemulsions (SFMEs) to reveal the properties and interactions within microemulsion systems. The area of interest is identified using these techniques, where silica nanoparticles are subsequently synthesized and then visualized using transmission electron microscopy (TEM).

Solvents prepared from natural terpenes (menthol and thymol), as H-bond acceptors, and a series of organic acids (chain lengths of 8, 10, and 14 C atoms), as H-bond donors, were characterized and tested as reaction media for liquid–liquid extraction purposes. Due to their high hydrophobicity, they seem to be promising alternatives to conventional (nonpolar and toxic) solvents, since they possess relatively less toxic, less volatile, and consequently, more environmentally friendly characteristics. Assuming that the equilibrium is established between solvent and analyte during a ligandless procedure, it can be concluded that those nonpolar solvents can efficiently extract nonpolar analytes from the aqueous environment. Previous investigations showed a wide range of applications, including their use as solvents in extractions of metal cations, small molecules, and bioactive compounds for food and pharmaceutical applications. In this work, hydrophobic solvents based on natural terpenes, which showed chemical stability and desirable physicochemical and thermal properties, were chosen as potential reaction media in the liquid–liquid extraction (LLE) procedure for Pb(II) removal from aqueous solutions. Low viscosities and high hydrophobicities of prepared solvents were confirmed as desirable properties for their application. Extraction parameters were optimized, and chosen solvents were applied. The results showed satisfactory extraction efficiencies in simple and fast procedures, followed by low solvent consumption. The best results (98%) were obtained by the thymol-based solvent, thymol–decanoic acid (Thy-DecA) 1:1, followed by L-menthol-based solvents: menthol–octanoic acid (Men-OctA) 1:1 with 97% and menthol–decanoic acid (Men-DecA) 1:1 with 94.3% efficiency.

Olive leaves are the richest source of phenolic compounds, particularly oleuropein, which has many beneficial effects on human health. This study compares the effect of three extraction techniques: ultrasonic-solvent extraction, microwave-assisted extraction, and supercritical CO2 extraction of freeze-dried wild olive leaves (Olea europea subps. oleaster, Hoffmanns. & Link) on oleuropein concentration in obtained extracts. The extract with the highest concentration of oleuropein was obtained after low-frequency ultrasound solvent extraction (WOLE-S) (71.97 µg/mL). Oleuropein from that extract showed low stability after simulated gastric digestion with human gastric juices (35.66%) and high stability after 60 min of intestinal phase (65.97%). The highest antiproliferative activity of WOLE-S and pure oleuropein was detected against T24 cancer cells. The antiproliferative activity of WOLE-S against MD-MBA-123, A549, and A1235 cells was moderate, while the activity of oleuropein was high. WOLE-S significantly down-regulated the expression of IL-6 in A549 cells, indicating a possible anti-inflammatory effect in lung cancer cells. The expression of IL-8 was slightly reduced by treating the cells with WOLE-S, while the expression of IL-10 was not altered by the treatment with WOLE-S or oleuropein.

Encapsulation of sinigrin in liposomes with the proliposomal method was performed in order to evaluate the effect of this process on in vitro simulated digestion and antioxidant potential of sinigrin. The recovery of sinigrin after simulated gastric and duodenal digestion of its free and liposomal forms was determined with HPLC-UV using human digestive juices. The antioxidant potential of sinigrin and sinigrin-loaded liposomes was determined with the Rancimat test as their ability to prolong oxidative stability of edible oil. The efficiency of 62% was obtained by encapsulating sinigrin in liposomes. The values of mean diameter, polydispersity index and zeta potential showed satisfactory size uniformity and physical stability of the liposomes containing sinigrin. Liposomes were shown to inhibit the digestion of sinigrin in both human gastric and intestinal juices, clearly enabling its prolonged release. Moreover, sinigrin in the liposomal form significantly prolonged the induction time of edible oil oxidation compared to its free form. The results obtained are encouraging from the point of view of a possible incorporation of the sinigrin-loaded liposomes in real functional food systems or their use as nutraceuticals.

Garlic (Allium sativum L.) is widely used in various food products and traditional medicine. Besides unique taste and flavour, it is well known for its chemical profile and bioactive potential. The aim of this study was to apply subcritical water extraction (SWE) and pressurized liquid extraction (PLE) for the extraction of bioactive compounds from the Ranco genotype of garlic. Moreover, PLE process was optimized using response surface methodology (RSM) in order to determine effects and optimize ethanol concentration (45–75%), number of cycles (1–3), extraction time (1–3 min) and temperature (70–110 °C) for maximized total phenols content (TP) and antioxidant activity evaluated by various in vitro assays. Furthermore, temperature effect in SWE process on all responses was evaluated, while allicin content (AC), as a major organosulphur compound, was determined in all samples. Results indicated that PLE provided tremendous advantage over SWE in terms of improved yield and antioxidant activity of garlic extracts. Therefore, high-pressure processes could be used as clean and green procedures for the isolation of garlic bioactives.

Considering the vast cultural and traditional heritage of the use of aromatic herbs and wildflowers for the treatment of light medical conditions in the Balkans, a comparison of the antioxidant capacity of wildflowers extracts from Herzegovina was studied using both cyclic voltammetry and spectrophotometry. The cyclic voltammograms taken in the potential range between 0 V and 800 mV and scan rate of 100 mV s−1 were used for the quantification of the electrochemical properties of polyphenols present in four aqueous plant extracts. Antioxidant capacity expressed as mmoL of gallic acid equivalents per gram of dried weight of the sample (mmoL GAE g−1 dw) was deduced from the area below the major anodic peaks (Q400 pH 6.0, Q500 pH 4.7, Q600 pH 3.6). The results of electrochemical measurements suggest that the major contributors of antioxidant properties of examined plants are polyphenolic compounds that contain ortho-dihydroxy-phenol or gallate groups. Using Ferric reducing-antioxidant power (FRAP) and 2,2′-azino-bis spectrophotometric methods (3-ethylbenzthiazoline-6-sulphonic acid) radical cation-scavenging activity (ABTS) additionally determined antioxidant capacity. The FRAP results ranged from 2.9702–9.9418 mmoL Fe/g dw, while the results for ABTS assays expressed as Trolox equivalents (TE) ranged from 14.1842–42.6217 mmoL TE/g dw. The Folin–Ciocalteu procedure was applied to determine the total phenolics content (TP). The TP content expressed as Gallic acid equivalents (GAE) ranged from 6.0343–9.472 mmoL GAE/g dw. The measurements of total flavonoid (TF) and total condensed tannin (TT) contents were also performed to obtain a broader polyphenolic profile of tested plant materials. Origanum vulgare L. scored the highest on each test, with the exception of TT content, followed by the Mentha × piperita L., Artemisia annua L., and Artemisia absinthium L., respectively. The highest TT content, expressed as mg of (−)catechin equivalents per gram of dried weight of sample (mg CE/g dw), was achieved with A. absinthium extract (119.230 mg CE/g dw) followed by O. vulgare (90.384 mg CE/g dw), A. annua (86.538 mg CE/g dw) and M. piperita (69.231 mg CE/g dw), respectively. In addition, a very good correlation between electrochemical and spectroscopic methods was achieved.

Natural phenolic compounds are recognized as bioactive ingredients in food but can also have a role as effective alternatives to synthetic antioxidants in stability improvement of foods prone to oxidation, such as edible oils. This study aimed at the preparation and HPLC-DAD characterization of phenolic extracts from Vaccinium corymbosum L. (raw, pasteurized, freeze-dried and treated with high-intensity ultrasound), and at testing their antioxidant potential in the prevention of olive oil oxidation in the native state and encapsulated into microemulsions and liposomes systems. Water-in-oil structured microemulsions used in this study were prepared using mechanical, ultrasonic, and high pressure homogenization. Liposomes with the average size of 589.1±2.9 nm were produced with the proliposome method using commercially available phosphatidylcholine – Phospolipon 90G. The obtained results showed significant prolongation of the oxidative stability of extra virgin olive oil enriched with encapsulated blueberry phenolic extracts than with native phenolic extracts, regardless of the method used for blueberry processing. Phenolic extracts encapsulated in microemulsions had a stronger effect on the prolongation of olive oil oxidative stability in comparison with the extracts encapsulated in liposomes. The average prolongation rate of oxidative stability was 45.65% by phenolic extracts encapsulated in microemulsions prepared by mechanical homogenization (p=0.012), and 58.72% by microemulsions prepared by ultrasound homogenization (p=0.011). Phenolic extracts encapsulated in microemulsions prepared by high pressure homogenization had no effect on oil oxidative stability prolongation.

Micellar systems are colloids with significant properties for pharmaceutical and food applications. They can be used to formulate thermodynamically stable mixtures to solubilize hydrophobic food-related substances. Furthermore, micellar formation is a complex process in which a variety of intermolecular interactions determine the course of formation and most important are the hydrophobic and hydrophilic interactions between surfactant–solvent and solvent–solvent. Glycols are organic compounds that belong to the group of alcohols. Among them, propane-1,2-diol (PG) is a substance commonly used as a food additive or ingredient in many cosmetic and hygiene products. The nature of the additive influences the micellar structure and properties of sodium dodecyl sulfate (SDS). When increasing the mass fraction of propane-1,2-diol in binary mixtures, the c.m.c. values decrease because propane-1,2-diol is a polar solvent, which gives it the ability to form hydrogen bonds, decreasing the cohesivity of water and reducing the dielectric constant of the aqueous phase. The values of ΔGm0 are negative in all mixed solvents according to the reduction in solvophobic interactions and increase in electrostatic interaction. With the rising concentration of cosolvent, the equilibrium between cosolvent in bulk solution and in the formed micelles is on the side of micelles, leading to the formation of micelles at a lower concentration with a small change in micellar size. According to the 1H NMR, with the addition of propylene glycol, there is a slight shift of SDS peaks towards lower ppm regions in comparison to the D2O peak. The shift is more evident with the increase in the amount of added propane-1,2-diol in comparison to the NMR spectra of pure SDS. Addition of propane-1,2-diol causes the upfield shift of the protons associated with hydrophilic groups, causing the shielding effect. This signifies that the alcohol is linked with the polar head groups of SDS due to its proximity to the SDS molecules.

A novel ion-selective electrode with membranes based on iron(III) phosphate and silver sulfide integrated into a completely new electrode body design has been developed for the determination of iron(III) cations. The best response characteristics with linear potential change were found in the iron(III) concentration range from 3.97 × 10−5 to 10−2 mol L−1. The detection limit was found to be 2.41 × 10−5 mol L−1 with a slope of −20.53 ± 0.63 and regression coefficient of 0.9925, while the quantification limit was 3.97 × 10−5 M. The potential change per concentration decade ranged from −13.59 ± 0.54 to −20.53 ± 1.56 for Electrode Body 1 (EB1) and from −17.28 ± 1.04 to −24 ± 1.87 for Electrode Body 2 (EB2), which is presented for the first time in this work. The prepared electrode has a long lifetime and the ability to detect changes in the concentration of iron cations within 20 s. Membrane M1 showed high recoveries in the determination of iron cations in iron(III) standard solutions (98.2–101.2%) as well as in two different pharmaceuticals (98.6–106.5%). This proves that this type of sensor is applicable in the determination of ferric cations in unknown samples, and the fact that all sensor parts are completely manufactured in our laboratory proves the simplicity of the method.

Direct potentiometric method for determination of penicillamine in pharmaceuticals by using commercial copper ISE is described. Proposed method is very inexpensive, simple and reasonably fast method for determination of Pen in acetic buffer, pH = 4 without pretreatment of pharmaceuticals. Determination is based on the reaction between Pen and Cu2+ from electrode membrane. Described method has linear response range for Pen from 2×10−6 to 1×10−2 mol L−1 with limit of detection of 1.1×10−6 mol L−1. Found concentrations of Pen are in very good agreement with declared ones with standard deviation values in range 4.00−4.50 %.

Microemulsions are optically isotropic and thermodynamically stable systems of water, oil and surfactant, often in combination with a cosurfactant which is required for optimal formation of microemulsion with a smaller aggregate radius and greater curvature of the interfacial layer. The full potential of microemulsion systems has yet to be realized and a lot of innovation in the field of microemulsion technology is expected. They have numerous advantages due to spontaneous formation, ease of manufacturing and scale-up, thermodynamic stability, ability to improve drug solubilization, and bioavailability. This work describes microemulsion systems which contain nonionic surfactants Tween 80 and Span 80, isopropyl myristate as the oil phase and purified water. From the most suitable microemulsion region, samples were selected and analyzed, blank and with encapsulated ascorbic acid, by measuring the size distribution of microemulsion aggregates, refractive index, electrical conductivity, and surface tension. [ABSTRACT FROM AUTHOR]