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Lignanoids are an active ingredient exerting powerful antioxidant and anti-inflammatory effects in the treatment of many diseases. In order to improve the efficiency of the resource utilization of traditional Chinese medicine waste, Magnolia officinalis Rehder & E.H.Wilson residue (MOR) waste biomass was used as raw material in this study, and a series of deep eutectic solvents (ChUre, ChAce, ChPro, ChCit, ChOxa, ChMal, ChLac, ChLev, ChGly and ChEG) were selected to evaluate the extraction efficiency of lignanoids from MORs. The results showed that the best conditions for lignanoid extraction were a liquid–solid ratio of 40.50 mL/g, an HBD-HBA ratio of 2.06, a water percentage of 29.3%, an extract temperature of 337.65 K, and a time of 107 min. Under these conditions, the maximum lignanoid amount was 39.18 mg/g. In addition, the kinetics of the extraction process were investigated by mathematic modeling. In our antioxidant activity study, high antioxidant activity of the lignanoid extract was shown in scavenging four different types of free radicals (DPPH, ·OH, ABTS, and superoxide anions). At a concentration of 3 mg/mL, the total antioxidant capacity of the lignanoid extract was 1.795 U/mL, which was equal to 0.12 mg/mL of Vc solution. Furthermore, the antibacterial activity study found that the lignanoid extract exhibited good antibacterial effects against six tested pathogens. Among them, Staphylococcus aureus exerted the strongest antibacterial activity. Eventually, the correlation of the lignanoid extract with the biological activity and physicochemical properties of DESs is described using a heatmap, along with the evaluation of the in vitro hypoglycemic, in vitro hypolipidemic, immunomodulatory, and anti-inflammatory activity of the lignanoid extract. These findings can provide a theoretical foundation for the extraction of high-value components from waste biomass by deep eutectic solvents, as well as highlighting its specific significance in natural product development and utilization. [ABSTRACT FROM AUTHOR]

Multifunctional materials with a coexistence of proton conduction properties, single–molecule magnet (SMM) behaviors and magneto–optical Faraday effects have rarely been reported. Herein, a new pair of Cu(II)–Dy(III) enantiomers, [DyCu2(RR/SS–H2L)2(H2O)4(NO3)2]·(NO3)·(H2O) (R–1 and S–1) (H4L = [RR/SS] –N,N′–bis [3–hydroxysalicylidene] –1,2–cyclohexanediamine), has been designed and prepared using homochiral Schiff–base ligands. R–1 and S–1 contain linear Cu(II)–Dy(III)–Cu(II) trinuclear units and possess 1D stacking channels within their supramolecular networks. R–1 and S–1 display chiral optical activity and strong magneto–optical Faraday effects. Moreover, R–1 shows a zero–field SMM behavior. In addition, R–1 demonstrates humidity– and temperature–dependent proton conductivity with optimal values of 1.34 × 10−4 S·cm−1 under 50 °C and 98% relative humidity (RH), which is related to a 1D extended H–bonded chain constructed by water molecules, nitrate and phenol groups of the RR–H2L ligand. [ABSTRACT FROM AUTHOR]

Citalopram (CIT) is a commonly prescribed medication for depression. However, the photodegradation mechanism of CIT has not yet been fully analyzed. Therefore, the photodegradation process of CIT in water is studied by density functional theory and time-dependent density functional theory. The calculated results show that during the indirect photodegradation process, the indirect photodegradation of CIT with ·OH occurs via OH-addition and F-substitution. The minimum activation energy of C10 site was 0.4 kcal/mol. All OH-addition and F-substitution reactions are exothermic. The reaction of 1O2 with CIT includes the substitution of 1O2 for F and an addition reaction at the C14 site. The Ea value of this process is 1.7 kcal/mol, which is the lowest activation energy required for the reaction of 1O2 with CIT. C–C/C–N/C–F cleavage is involved in the direct photodegradation process. In the direct photodegradation of CIT, the activation energy of the C7-C16 cleavage reaction was the lowest, which was 12.5 kcal/mol. Analysis of the Ea values found that OH-addition and F-substitution, the substitution of 1O2 for F and addition at the C14 site, as well as the cleavage reactions of C6–F/C7–C16/C17–C18/C18–N/C19–N/C20–N are the main pathways of photodegradation of CIT. [ABSTRACT FROM AUTHOR]

Platinum nanoparticles (PtNPs) are classical peroxidase-like nanozyme; self-agglomeration of nanoparticles leads to the undesirable reduction in stability and catalytic activity. Herein, a hybrid peroxidase-like nanocatalyst consisting of PtNPs in situ growing on g–C3N4 nanosheets with enhanced peroxidase-mimic catalytic activity (PtNP@g–C3N4 nanosheets) was prepared for H2O2 and oxidase-based colorimetric assay. g–C3N4 nanosheets can be used as carriers to solve the problem of poor stability of PtNPs. We observed that the catalytic ability could be maintained for more than 90 days. PtNP@g–C3N4 nanosheets could quickly catalyze the oxidation of 3,3′,5,5′-tetramethylbenzidine (TMB), and the absorbance of blue color oxidized TMB (oxTMB) showed a robust linear relationship with the concentration of H2O2 (the detection limit (LOD): 3.33 μM). By utilizing H2O2 as a mediator, this strategy can be applied to oxidase-based biomolecules (glucose, organophosphorus, and so on, that generate or consume hydrogen peroxide) sensing. As a proof of concept, a sensitive assay of cholesterol that combined PtNP@g–C3N4 nanosheets with cholesterol oxidase (ChOx) cascade catalytic reaction was constructed with an LOD of 9.35 μM in a widespread range from 10 to 800 μM (R2 = 0.9981). In addition, we also verified its ability to detect cholesterol in fetal bovine serum. These results showed application prospect of PtNP@g–C3N4 nanosheets-based colorimetry in sensing and clinical medical detection. [ABSTRACT FROM AUTHOR]

In this study, we report on the synthesis of new organoselenium derivatives, including nonsteroidal anti-inflammatory drugs (NSAIDs) scaffolds and Se functionalities (isoselenocyanate and selenourea), which were evaluated against four types of cancer cell line: SW480 (human colon adenocarcinoma cells), HeLa (human cervical cancer cells), A549 (human lung carcinoma cells), MCF-7 (human breast adenocarcinoma cells). Among these compounds, most of the investigated compounds reduced the viability of different cancer cell lines. The most promising compound 6b showed IC50 values under 10 μM against the four cancer cell lines, particularly to HeLa and MCF-7, with IC50 values of 2.3 and 2.5 μM, respectively. Furthermore, two compounds, 6b and 6f, were selected to investigate their ability to induce apoptosis in MCF-7 cells via modulation of the expression of anti-apoptotic Bcl-2 protein, pro-inflammatory cytokines (IL-2) and proapoptotic caspase-3 protein. The redox properties of the NSAIDs-Se derivatives were conducted by 2, 2-didiphenyl-1-picrylhydrazyl (DPPH), bleomycin-dependent DNA damage and glutathione peroxidase (GPx)-like assays. Finally, a molecular docking study revealed that an interaction with the active site of thioredoxin reductase 1 (TrxR1) predicted the antiproliferative activity of the synthesized candidates. Overall, these results could serve as a promising launch point for further designs of NSAIDs-Se derivatives as potential antiproliferative agents. [ABSTRACT FROM AUTHOR]

DNA-templated fluorescent nanoclusters (NCs) have attracted increasing research interest on account of their prominent features, such as DNA sequence-dependent fluorescence, easy functionalization, wide availability, water solubility, and excellent biocompatibility. Coupling DNA templates with complementary DNA, aptamers, G-quadruplex, and so on has generated a large number of sensors. Additionally, the preparation and applications of DNA-templated fluorescent NCs in these sensing have been widely studied. This review firstly focuses on the properties of DNA-templated fluorescent NCs, and the synthesis of DNA-templated fluorescent NCs with different metals is then discussed. In the third part, we mainly introduce the applications of DNA-templated fluorescent NCs for sensing metal ions. At last, we further discuss the future perspectives of DNA-templated fluorescent NCs in the synthesis and sensing metal ions in the environmental and biological fields. [ABSTRACT FROM AUTHOR]

The typical compounds of Aurantii fructus (AF) reported in previous research were screened for their high antagonistic ability on the D2 dopamine receptor (D2R) in silico, and then bioactivity-guided separation was undertaken on the potential D2R antagonists from AF using high-speed counter-current chromatography (HSCCC). Three flavanones, two polymethoxyflavonoids, and three coumarins were effectively isolated from ethanol extracts of Aurantii fructus (AF) by the use of a two-step HSCCC method, and their chemical structures were identified by mass spectrometry, 1H-NMR, and 13C-NMR and compared with published data. Firstly, crude extract of 70% ethanol eluent (150 mg) was isolated by HSCCC using an n-hexane−ethyl acetate−n-butanol−methanol−0.05% acetic acid (1:3:1.8:1:5, v/v/v/v/v) solvent system, and compounds 1 (naringin, 28 mg), 2 (neohesperidin, 13 mg), 3 (meranzin, 5 mg) and 4 (poncirin, 3 mg) were successfully isolated with 98.5%, 95.1%, 97.7%, and 92.4% purity, respectively. Then, the crude extract of 95% ethanol eluent (120 mg) was isolated by n-hexane−n-butanol−ethanol (methanol)−0.05% acetic acid (2:0.6:1:3, v/v/v/v) solvent system and compounds 3 (meranzin, 3 mg), 5 (meranzin hydrate, 4 mg), 6 (isomeranzin, 6 mg), 7 (nobiletin, 10 mg), and 8 (tangeretin, 7 mg) were successfully isolated with 95.8%, 98.5%, 95.1%, 92.4%, and 97.7% purity, respectively. Naringenin, a parent structure of naringin with the excellent binding score of −9.3 kcal/mol, was completely in conjunction with the active site of D2R, indicating that it is critical for the treatment of gastrointestinal dysfunction. The results indicated that the bioactivity-guided method is practical for the effective separation of active compounds from natural resources. [ABSTRACT FROM AUTHOR]

It is always a difficult task to assign the peaks recorded from a vibrational spectrum. Herein, we explored a new pathway of density functional theory (DFT) simulation to present three kinds of spectra of ice XIV that can be referenced as inelastic neutron scattering (INS), infrared (IR), and Raman experimental spectrum. The INS spectrum is proportional to the phonon density of states (PDOS) while the photon scattering signals reflect the normal vibration frequencies near the Brillouin zone (BZ) center. Based on good agreements with the experimental data, we identified the relative frequency and made scientific assignments through normal vibration modes analysis. The two hydrogen bond (H-bond) peaks among the ice phases from INS were discussed and the dynamic process of the H-bond vibrations was found to be classified into two basic modes. We deduced that two H-bond modes are a general rule among the ice family and more studies are ongoing to investigate this subject. [ABSTRACT FROM AUTHOR]