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"Green chemistry" describes the development of new technologies that reduce or eliminate the need for hazardous compounds or the production of them. In order to accomplish this goal, we have developed a new magnetic recyclable biocatalyst in this study by successfully applying aspartic acid to magnetic nanoparticles. Aspartic acid's molecular makeup made it possible for it to stabilize on magnetic nanoparticles using a straightforward method. We characterized the synthesized catalyst using microscopic and spectroscopic techniques such as Fourier transform infrared (FT-IR), X-ray diffraction (XRD), Field emission scanning electron microscopy (FE-SEM), Energy-dispersive X-ray spectroscopy (EDS), vibrating sample magnetometer (VSM) and transmission electron microscopy (TEM). The catalytic activity of this organocatalyst was evaluated for the synthesis of benzo[b]pyran and pyrano[3,2-c] chromene derivatives, exhibiting excellent efficiency. This protocol offers several benefits, such as using a low-cost biocatalyst, nontoxicity, high product yield, easy separation, short reaction times, catalyst reusability, and H 2 O/EtOH solvent. In summary, our research indicates a feasible approach towards developing a novel magnetic biocatalyst suitable for application in organic synthesis., Competing Interests: Competing interests: The authors declare no competing interests., (© 2024. The Author(s).)

The International Maritime Organization (IMO) has implemented new sulfur content regulations for marine fuels in response to growing environmental concerns, including global warming. These regulations severely and costly restrict refinery operations. Oxidative desulfurization (ODS) is an attractive desulfurization method that has advantages such as mild operating conditions and a hydrogen-free process over traditional processes such as hydrodesulfurization (HDS). One can employ oxidative desulfurization in addition to or instead of hydrodesulfurization. Organic sulfur molecules undergo oxidative desulfurization, which results in the formation of polar sulfones. The refined fuel oil is then separated from the oxidized sulfones using methods such liquid-liquid extraction, distillation, and absorption. This work examines and simulates the process of separating sulfur-containing oxidized chemicals from fuel oil utilizing oxidative desulfurization technology. Acetic acid served as the catalyst and hydrogen peroxide as the chosen oxidant. This effort involved simulating the oxidative desulfurization of fuel oil and then using absorption methods to separate the oxidized sulfones. Subsequent procedures including absorption and distillation were used to separate and recover the resultant effluent, solvent, and oxidant from the remaining components. According to the simulation results, the procedure was run at 80 °C and a modest pressure of less than 5 bar. Sulfur content in the original hydrocarbon fuel was 3.5% by weight; at the output, it was less than 0.5% by weight. The findings of the sensitivity analysis of a few key factors demonstrated that the conversion percentage increased from 84 to 98% when the reactor's diameter was changed from 0.5 to 1.2 m and its length was extended to the desired amount. The reaction conversion percentage has increased significantly when the mass flow rate of hydrogen peroxide is increased from 0.5 to 1.5 kg/h, the pressure is increased from 1.5 to 5 bar, and the temperature is raised to 30 °C. According to the process optimization data, the ideal state had an exergy efficiency of 55.57%, a solvent waste rate of 1.75%, and a sulfur content of 0.22% in the fuel., Competing Interests: Declarations. Competing interests: The authors declare no competing interests., (© 2024. The Author(s).)

Ionizing radiations are a helpful technique and have improved financial potential in developing new and unique commercially important fruit tree varieties. The 'Yaghouti' grape cuttings were treated with 0 (control), 10, 20, 30, 40, 50, 60, 70, 80, 90, and 100 Gy gamma ray (γ) doses. The objectives of this study were to (1) investigate the effects of γ radiation on the survival rate, leaves, shoots, and root morphometric traits after γ irradiation; (2) Measurement of the 25, 50, and 75% lethal dose and 25, 50, and 75% growth reduction dose based on leaves, shoots, and root morphometric characteristics to estimate grape radiosensitivity; (3) Ultimately, determining the optimum dose of γ irradiation based biological responses (LD 25, 50, 75 and GR 25, 50, 75 ) in Yaghouti grape. The findings demonstrate that the lethal dose of the 'Yaghouti' was 18 Gy for LD 25 , 30 Gy for LD 50 , and 48 Gy for LD 75 , respectively. Furthermore, our findings showed that increasing the γ dose had a harmed ngative effect on vine growth, as evidenced by a decrease in plant height, root number, root volume, leaf area, aerial biomass, root biomass, and internode number of the 'Yaghouti' grape plants. Our results showed that between the aerial parts of vines, the leaf area and aerial biomass had higher radiosensitivity than plant height and other aerial parts of the plants based on data from GR 25 , GR 50 , and GR 75 . Moreover, GR studies of root characteristics revealed that root number and biomass root had higher radiation sensitivity than root volume. According to biological responses (LD 25, 50, 75 and GR 25, 50, 75 ) in the 'Yaghouti' grape, 30 Gy of γ radiation is the optimum dose for preliminary mutagenesis investigations., (© 2023. The Author(s).)

Periodontitis is a chronic inflammatory disease characterized by the release of matrix metalloproteinases (MMPs) from resident connective tissue cells in tooth-supporting tissues (periodontium). Platelet activation, and the attendant release of pro-inflammatory chemokines such as platelet factor 4 (CXCL4/PF4), are associated with periodontitis although the associated biochemical pathways remain undefined. Here we report that recombinant PF4 is internalized by cultured human gingival fibroblasts (hGFs), resulting in significant (p < 0.05) upregulation in both the production and release of MMP-2 (gelatinase A). This finding was corroborated by elevated circulating levels of MMP-2 (p < 0.05) in PF4-overexpressing transgenic mice, relative to controls. We also determined that PF4 induces the phosphorylation of NF-κB; notably, the suppression of NF-κB signaling by the inhibitor BAY 11-7082 abrogated PF4-induced MMP-2 upregulation. Moreover, the inhibition of surface glycosaminoglycans (GAGs) blocked both PF4 binding and NF-κB phosphorylation. Partial blockade of PF4 binding to the cells was achieved by treatment with either chondroitinase ABC or heparinase III, suggesting that both chondroitin sulfate and heparan sulfate mediate PF4 signaling. These results identify a novel pathway in which PF4 upregulates MMP-2 release from fibroblasts in an NF-κB- and GAG-dependent manner, and further our comprehension of the role of platelet signaling in periodontal tissue homeostasis., (© 2022. The Author(s).)

Diabetic retinopathy is a severe microvascular problem in diabetes mellitus. Silymarin is a flavonoid compound, and according to previous studies, it is a bioactive compound with potent antioxidant and anti-inflammatory properties. This investigation aims to peruse the impact of silymarin against diabetic retinopathy in streptozotocin (STZ)-provoked rats. Thirty-two adult male Wistar rats were randomly allocated into the control group, STZ group, STZ + silymarin (50 mg/kg), and STZ + silymarin (100 mg/kg). STZ rats received silymarin every day until 2 months after diabetes induction. The serum and retinal tissues were collected 2 months after silymarin treatment to determine biochemical and molecular analyses. Silymarin markedly lowered the serum glucose concentration in diabetic rats. Silymarin reduced the increased levels of advanced glycosylated end products (AGEs), the receptors for AGEs (RAGE), and reactive oxygen species (ROS) in diabetic rats. Silymarin also attenuated the phosphorylation of p38 MAP kinase and nuclear factor (NF)-κB p65 and diminished diabetes-induced overexpression of inflammatory cytokines, vascular endothelial growth factor (VEGF), adhesion molecules, and extracellular matrix proteins in STZ rats. Our data suggested that silymarin has protective effects against diabetic retinopathy, which might be related to the inhibition of the AGEs/RAGE axis and its antioxidant and anti-inflammatory activities., (© 2022. The Author(s).)

In this study, actual swage waste activated sludge in batch reactors was employed to assess the synergistic effect of free nitrous acid and Fenton pre-treatments on enhancing methane production in the anaerobic digestion process. In addition to methane enhancement, the mechanisms driving the enhancement were also investigated via measuring enzymes activity and solubilisation of organic matter. This study revealed that the combined pre-treatments solubilised organic matter significantly more than the bioreactors pre-treated with individual FNA and Fenton. For understanding the influence of pre-treatments on solubilisation of organic matter, soluble protein, soluble polysaccharide and soluble chemical oxygen demand (SCOD) were measured before and after the treatments and it was shown that they respectively increased by 973%, 33% and 353% after the treatments. Protease and cellulase activity, as the key constituents of the microbial community in activated sludge, decreased considerably after the combined pre-treatments 42% and 32% respectively, which resulted in considerable methane enhancement. The results corroborate the synergy of the combined FNA and Fenton pre-treatment in degrading the organic and microbial constituents in waste activated sludge, paving the way for the big-scale implementation of these technologies.

Peptidyl-tRNA dissociation from ribosomes is an energetically costly but apparently inevitable process that accompanies normal protein synthesis. The drop-off products of these events are hydrolysed by peptidyl-tRNA hydrolase. Mutant selections have been made to identify genes involved in the drop-off of peptidyl-tRNA, using a thermosensitive peptidyl-tRNA hydrolase mutant in Escherichia coli. Transposon insertions upstream of the frr gene, which encodes RF4 (ribosome release or recycling factor), restored growth to this mutant. The insertions impaired expression of the frr gene. Mutations inactivating prfC, encoding RF3 (release factor 3), displayed a similar phenotype. Conversely, production of RF4 from a plasmid increased the thermosensitivity of the peptidyl-tRNA hydrolase mutant. In vitro measurements of peptidyl-tRNA release from ribosomes paused at stop signals or sense codons confirmed that RF3 and RF4 were able to stimulate peptidyl-tRNA release from ribosomes, and showed that this action of RF4 required the presence of translocation factor EF2, known to be needed for the function of RF4 in ribosome recycling. When present together, the three factors were able to stimulate release up to 12-fold. It is suggested that RF4 may displace peptidyl-tRNA from the ribosome in a manner related to its proposed function in removing deacylated tRNA during ribosome recycling.

We studied the dissociation rates of peptidyl-tRNA from the P-site of poly(U)-programmed wild-type Escherichia coli ribosomes, hyperaccurate variants altered in S12 (SmD, SmP) and error-prone variants (Ram) altered in S4 or S5. The experiments were carried out in the presence and absence of streptomycin, and the effects of neomycin were tested in the wild-type ribosomes. Binding of peptidyl-tRNA to the P-site of wild-type ribosomes is much stronger than to their A-site. Addition of streptomycin dramatically reduces its affinity for the P-site. The S12 alternations make the P-site binding of peptidyl-tRNA much tighter, and the S4, S5 alterations make it weaker than in the case of the wild-type. We find that when binding of peptidyl-tRNA to the A-site is weak, then the affinity for the P-site is stronger, and vice versa. From these results, we formulate a hypothesis for the actions of streptomycin and neomycin based on deformations of the 16S rRNA tertiary structure. The results are also used to interpret some in vivo experiments on translational processivity.