Novel high-efficient adsorbent based on modified gelatin/montmorillonite nanocomposite for removal of malachite green dye.

Shortage of drinking water has gained potential interest over the last few decades. Discharged industrial effluent, including various toxic pollutants, to water surfaces is one of the most serious environmental issues. The adsorption technique has become a widely studied method for the removal of toxic pollutants, specifically synthetic dyes, from wastewater due to its cost-effectiveness, high selectivity, and ease of operation. In this study, a novel gelatin-crosslinked-poly(acrylamide-co-itaconic acid)/montmorillonite (MMT) nanoclay nanocomposites-based adsorbent has been prepared for removing malachite green (MG) dye from an aqueous solution. Modified gelatin nanocomposites were synthesized using a free-radical polymerization technique in the presence and absence of MMT. Various analytical instrumentation: including FTIR, FESEM, XRD, and TEM techniques were used to elucidate the chemical structure and surface morphology of the prepared samples. Using a batch adsorption experiment, Langmuir isotherm model showed that the prepared modified gelatin nanocomposite had a maximum adsorption capacity of 950.5 mg/g using 350 mg/L of MG dye at pH 9 within 45 min. Furthermore, the regeneration study showed good recyclability for the obtained nanocomposite through four consecutive reusable cycles. Therefore, the fabricated gelatin nanocomposite is an attractive adsorbent for MG dye elimination from aqueous solutions.

Molecular characteristics and zoonotic potential of enteric protists in domestic dogs and cats in Egypt.

Introduction: Domestic dogs and cats can be a source of human infection by a wide diversity of zoonotic pathogens including parasites. Genotyping and subtyping tools are useful in assessing the true public health relevance of canine and feline infections by these pathogens. This study investigated the occurrence, genetic diversity, and zoonotic potential of common diarrhea-causing enteric protist parasites in household dogs and cats in Egypt, a country where this information is particularly scarce. Methods: In this prospective, cross-sectional study a total of 352 individual fecal samples were collected from dogs (n = 218) and cats (n = 134) in three Egyptian governorates (Dakahlia, Gharbeya, and Giza) during July-December 2021. Detection and identification of Cryptosporidium spp., Giardia duodenalis, Enterocytozoon bieneusi, and Blastocystis sp. were carried out by PCR and Sanger sequencing. Basic epidemiological variables (geographical origin, sex, age, and breed) were examined for association with occurrence of infection by enteric protists. Results and discussion: The overall prevalence rates of Cryptosporidium spp. and G. duodenalis were 1.8% (95% CI: 0.5-4.6) and 38.5% (95% CI: 32.0-45.3), respectively, in dogs, and 6.0% (95% CI: 2.6-11.4) and 32.1% (95% CI: 24.3-40.7), respectively, in cats. All canine and feline fecal samples analyzed tested negative for E. bieneusi and Blastocystis sp. Dogs from Giza governorate and cats from Dakahlia governorate were at higher risk of infection by Cryptosporidium spp. (p = 0.0006) and G. duodenalis (p = 0.00001), respectively. Sequence analyses identified host-adapted Cryptosporidium canis (n = 4, one of them belonging to novel subtype XXe2) and G. duodenalis assemblages C (n = 1) and D (n = 3) in dogs. In cats the zoonotic C. parvum (n = 5) was more prevalent than host-adapted C. felis (n = 1). Household dogs had a limited (but not negligible) role as source of human giardiasis and cryptosporidiosis, but the unexpected high frequency of zoonotic C. parvum in domestic cats might be a public health concern. This is the first molecular-based description of Cryptosporidium spp. infections in cats in the African continent to date. Molecular epidemiological data provided here can assist health authorities and policy makers in designing and implementing effective campaigns to minimize the transmission of enteric protists in Egypt.

Nano Pt/TiO2 photocatalyst for ultrafast production of sulfamic acid derivatives using 4-nitroacetanilides as nitrogen precursor in continuous flow reactors.

The design of reactors based on high performance photocatalysts is an important research in catalytic hydrogenation. In this work, modification of titanium dioxide nanoparticles (TiO2 NPs) was achieved by preparation of Pt/TiO2 nanocomposites (NCs) through photo-deposition method. Both nanocatalysts were used for the photocatalytic removal of SOx from the flue gas at room temperature in the presence of hydrogen peroxide, water, and nitroacetanilide derivatives under visible light irradiation. In this approach, chemical deSOx was achieved along with protection of the nanocatalyst from sulfur poising through the interaction of the released SOx from SOx-Pt/TiO2 surface with p-nitroacetanilide derivatives to produce simultaneous aromatic sulfonic acids. Pt/TiO2 NCs have a bandgap of 2.64 eV in visible light range, which is lower than the bandgap of TiO2 NPs, whereas TiO2 NPs have a mean size of 4 nm and a high specific surface area of 226 m2/g. Pt/TiO2 NCs showed high photocatalytic sulfonation of some phenolic compounds using SO2 as a sulfonating agent along with the existence of p-nitroactanilide derivatives. The conversion of p-nitroacetanilide followed the combination processes of adsorption and catalytic oxidation-reduction reactions. Construction of an online continuous flow reactor-high-resolution time-of-flight mass spectrometry system had been investigated, realizing real-time and automatic monitoring of completion the reaction. 4-nitroacetanilide derivatives (1a-1e) was converted to its corresponding sulfamic acid derivatives (2a-2e) in 93-99% isolated yields of within 60 s. It is expected to offer a great opportunity for ultrafast detection of pharmacophores.

Siwa Oasis groundwater quality: factors controlling spatial and temporal changes.

Siwa Oasis is of great historical, environmental, and scientific importance, as it contains unique archeological and geological features. Groundwater is the main source of freshwater in that oasis. The carbonate aquifer groundwater, used for irrigation, was sampled to evaluate factors controlling quality changes spatially and temporally by applying hydrochemical and statistical analyses. The salinity of the aquifer varied spatially from 1367 to 8645 mg/l based on one hydrogeological condition, with the highest TDS (> 5432.5 mg/l, 25% of samples) at the central part of the study area. Temporally, the salinity changed slightly from 3754.3 mg/l (in 2014) to 4222.4 mg/l (in 2020). The cession of illegal wells, pumping control, and excavation of formed salts have a noticeable impact on salinity (mediate the increase in salinity) and ions. However, about 61% of the studied samples can be considered unsuitable for irrigation owing to salinity and can harm plant yield. The heavy metals studied (Fe, Mn, Cu, Pb), except Cd, were within the permissible limit for irrigation water. Finally, it is proposed to construct desalination stations to enhance water quality for irrigation in the study area and set up many companies for salt extraction.

Implementation of graphitic carbon nitride nanomaterials and laser irradiation for increasing bioethanol production from potato processing wastes.

Agricultural and agro-industrial wastes (e.g., potato peel waste) are causing severe environmental problems. The processes of pretreatment, saccharification, and fermentation are the major obstacles in bioethanol production from wastes and must be overcome by efficient novel techniques. The effect of exposing the fungi (yeast) Saccharomyces cerevisiae to laser source with the addition of graphitic carbon nitride nanosheets (g-C3N4) with different concentrations on bioethanol production was investigated through the implementation of a batch anaerobic system and using potato peel waste (PPW). Dichromate test was implemented as quantitative analysis for quantification of the bioethanol yield. The benefits of this test were the appearance of green color indicating the identification of ethanol (C2H5OH) by bare eye and the ease to calculate the bioethanol yield through UV-visible spectrophotometry. The control sample (0.0 ppm of g-C3N4) showed only a 4% yield of bioethanol; however, by adding 150 ppm to PPW medium, 22.61% of ethanol was produced. Besides, laser irradiations (blue and red) as influencing parameters were studied with and without the addition of g-C3N4 nanomaterials aiming to increase the bioethanol. It was determined that the laser irradiation can trigger the bioethanol production (in case of red: 13.13% and in case of blue: 16.14% yields, respectively) compared to the control sample (in absence of g-C3N4). However, by adding different concentrations of g-C3N4 nanomaterials from 5 to 150 ppm, the bioethanol yield was increased as follows: in case of red: 56.11% and, in case of blue: 56.77%, respectively. It was found that using fungi and exposing it to the blue laser diode source having a wavelength of 450 nm and a power of 250 mW for a duration of 30 min with the addition of 150 mg L-1 of g-C3N4 nanomaterials delivered the highest bioethanol yield from PPW.

Photocatalytic oxidation of nitrogen oxides (NOx) using Ag- and Pt-doped TiO2 nanoparticles under visible light irradiation.

In this work, titanium dioxide nanoparticles (TiO2 NPs) and modified TiO2 NPs with silver (Ag) or platinum (Pt) dopant were developed through photodeposition method for the NOx conversion into nitric acid (HNO3) under visible light irradiation. The formed photocatalysts TiO2, Ag/TiO2, and Pt/TiO2 nanocomposites were characterized by utilizing TEM, SEM, energy-dispersive X-ray analysis (EDX), XRD, UV/visible diffuse reflectance spectroscopy (UV-Vis DRS), and FT-IR. It had been investigated that an enhancement within the conversion of NOx into HNO3 was increased from 34.3 to 78.3% for Ag/TiO2 and from 35.2 to 78.5% for Pt/TiO2 under visible light irradiation conditions at room temperature for less than 2 h. The photodegradation rate order of NOx under visible light irradiation is Pt/TiO2 ~ Ag/TiO2 > TiO2. A possible mechanism for the catalytic conversion of NOx gases has been proposed, which depends on the photogeneration of electrons and holes after the excitation of nanocatalysts under visible radiation that promoted superoxide and hydroxyl ions, which can depredate NOx gases. This approach of NOx photocatalytic conversion is characterized by its chemical stability, low cost, high efficiency, simple operation, and strong durability than traditional methods.

Polyunsaturated fatty acid-derived chromones exhibiting potent antioxidant activity.

The marine polyunsaturated lipid-derived natural product all-(Z)-5,7-dihydroxy-2-(4Z,7Z,10Z,13Z,16Z-nonadecapentaenyl) (1) and four analogs 5-8 have been synthesized and evaluated as antioxidants in two cell-based assays. The natural product 1 and the analog 5 exhibited interesting antioxidant effects with IC50-values of 14±9 and 29±3µM, respectively, in a cellular lipid peroxidation antioxidant activity assay using HepG2 cells. Moreover, in the HepG2 cellular antioxidant activity assay, the natural product 1 exhibited strong protective effects against reactive oxygen species with an IC50=160±25µM.