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Mycotoxins can accumulate in various feeds and thus may get in duck meat, which may have severe food safety and public health implications. This study examined mycotoxins and veterinary medications in duck meat marketed in eight marketplaces around China. For the determination of mycotoxins, including the mycotoxins aflatoxin B1 (AFB1), aflatoxin B2 (AFB2), aflatoxin M1 (AFM1), T-2 toxin, zearalenone (ZEN), and ochratoxin A (OTA), a liquid-chromatography tandem mass spectrometry (LC-MS/MS) method was validated. Overall, 13 out of 48 samples (27%) presented AFB1, and AFB2 was present in 14 out of 48 samples with positive levels ranging from 0.5 μg/kg (gizzard) to 4.1 μg/kg (lung). Eleven samples were contaminated with AFM1. T-2 was also found in three parts of duck samples (duck gizzard, neck, and lung), and the 5th and 48th samples were contaminated with T-2. ZEN was found in 5 of 48 analyzed samples (10%), and OTA was present in 21 out of 48 samples. The maximum kinds of mycotoxins found simultaneously in duck samples were six in duck lungs. High co-occurrence of mycotoxins was verified in several samples. The detection rate of various veterinary drugs was 0–12.5% in duck meat samples, and the over standard rate was 2.1%. Co-occurrence of veterinary drugs was verified in several samples.

Nowadays, photocatalytic technologies are regarded as promising strategies to solve energy problems, and various photocatalysts have been synthesized and explored. In this paper, a novel CdS/MoO2@Mo2C-MXene photocatalyst for H2 production was constructed by a two-step hydrothermal method, where MoO2@Mo2C-MXene acted as a binary co-catalyst. In the first hydrothermal step, MoO2 crystals with an egged shape grew on the surface of two-dimensional (2D) Mo2C MXene via an oxidation process in HCl aqueous solution. In the second hydrothermal step, CdS nanorods were uniformly assembled on the surface of MoO2@Mo2C-MXene in ethylenediamine with an inorganic cadmium source and organic sulfur source. The CdS/MoO2@Mo2C-MXene composite with MoO2@Mo2C-MXene of 5 wt% exhibits an ultrahigh visible-light photocatalytic H2 production activity of 22,672 µmol/(g·h), which is ∼21% higher than that of CdS/Mo2C-MXene. In the CdS/MoO2@Mo2C-MXene composite, the MoO2 with metallic nature separates CdS and Mo2C MXene, which acts as an electron-transport bridge between CdS and Mo2C MXene to accelerate the photoinduced electron transferring. Moreover, the energy band structure of CdS was changed by MoO2@Mo2C-MXene to suppress the recombination of photogenerated carriers. This novel compound delivers upgraded photocatalytic H2 evolution performance and a new pathway of preparing the low-cost photocatalyst to solve energy problems in the future.

In the work, a novel filamentou sodium alginate (SA) /ε-polylysine (PL) fiber with excellent mechanical properties and controllable sizes is prepared in an efficient and environmentally friendly manner via continuous pulling of an electrostatically assembled SA/PL composites at the contact interface of aqueous solutions of cationic polyelectrolyte ε-PL and anionic natural polysaccharide SA. The SA/PL fiber exhibits good antibacterial activity, low cytotoxicity, anti-hemolysis, bioadhesion, and environmental friendliness due to its natural raw materials and green preparation process. In vivo experiments have shown that the SA/PL fiber can promote the healing and repair of skin wounds on the backs of mice via resistance to pathogen infection, reduction of inflammation, and anti-allogeneic allergy of the wound. In summary, these results demonstrate that the SA/PL fiber is a green and biosafe multifunctional natural polymer material, with potential applications in suturing wound.

Carboxymethyl chitosan (CMCS)-based complex coacervate has attracted much attention in drug oral delivery due to its pH-responsive property. As a unique ampholyte polymer, the self-coacervation of CMCS has great research potential. In this work, CMCS self-coacervates were prepared by adjusting the pH of the CMCS aqueous solution close to its isoelectric point. The Fourier-transformed infrared spectroscopy (FTIR) results revealed that electrostatic interactions, hydrogen bonding, and hydrophobic interactions were involved in the self-coacervation of CMCS. The obtained self-coacervates presented a dense surface structure, and were stable at a wide pH range of 3.0–6.0, and gradually dissolved under basic conditions. Although self-coacervation decreased the crystallinity and thermal stability of CMCS, the obtained coacervates showed excellent pH-responsive properties and ionic strength stability. We also investigated its potential in lactoferrin (LF) encapsulation and oral delivery. The CMCS self-coacervates exhibited a high encapsulation efficiency (EE) of 94.79 ± 0.49% and loading capacity (LC) of 26.29 ± 0.52% when the addition amount of LF was 2 mg. The simulated gastric digestion results demonstrated that CMCS self-coacervates could protect more than 80% of LF from hydrolysis and maintain the bioactivities of LF. Accordingly, the self-coacervation of CMCS could be used as a pH-responsive encapsulation and delivery strategy.

The removal of nitric oxide is an important environmental issue, as well as a necessary prerequisite for achieving high efficiency of CO2 electroreduction. To this end, the electrocatalytic denitrification is a sustainable route. Herein, we employ reaction phase diagram to analyze the evolution of reaction mechanisms over varying catalysts and study the potential/pH effects over Pd and Cu. We find the low N2 selectivity compared to N2O production, consistent with a set of experiments, is limited fundamentally by two factors. The N2OH* binding is relatively weak over transition metals, resulting in the low rate of as-produced N2O* protonation. The strong correlation of OH* and O* binding energies limits the route of N2O* dissociation. Although the experimental conditions of varying potential, pH and NO pressures can tune the selectivity slightly, which are insufficient to promote N2 selectivity beyond N2O and NH3. A possible solution is to design catalysts with exceptions to break the scaling characters of energies. Alternatively, we propose a reverse route with the target of decentralized ammonia synthesis.

In this study, the recovery of pecan nut kernel oil (PNKO) obtained by mechanical pressing (MP) was compared with that obtained by ultrasonic-assisted aqueous enzymatic extraction (UAAEE). At the same time, contents of substances with proven bioactivity, fatty acid compositions, physicochemical properties and antioxidant activities of PNKO were also assessed. Obviously, the oil yield obtained by UAAEE (71.32%) was higher than that obtained by MP (56.81%). Therefore, Plackett-Burman design (PBD), as well as Box-Behnken design (BBD), further optimized the UAAEE process, and the highest oil yield of 78.83% was acquired under the following conditions: incubation time of 2 h, the mixed enzyme (cell ulase+hemicellulase+pectinase+neutrase, w/w/w/w=1/1/1/1) concentration of 2.9%, liquid-solid ratio of 4 mL/g, pH of 4, particle size of 300 μm, ultrasonic time of 20 min, ultrasonic power of 432 W and reaction temperature of 53°C. The PNKO obtained by the two methods possessed similar fatty acid composition, but that obtained by UAAEE had comparatively low acid value and peroxide value. Moreover, rich content of total phenolics, squalene and phytosterols, as well as strong scavenging activities against DPPH and ABTS

Recently, electrochemical NO reduction (eNORR) to ammonia has attracted enormous research interests due to the dual benefits in ammonia synthesis and denitrification fields. Herein, taking Ag as a model catalyst, we have developed a microkinetic model to rationalize the general selectivity trend of eNORR with varying potential, which has been observed widely in experiments, but not understood well. The model reproduces experiments well, quantitatively describing the selectivity turnover from N2O to NH3 and from NH3 to H2 with more negative potential. The first turnover of selectivity is due to the thermochemical coupling of two NO* limiting the N2O production. The second turnover is attributed to the larger transfer coefficient (β) of HER than NH3 production. This work reveals how electrode potential regulate the selectivity of eNORR, which is also beneficial to understand the commonly increasing HER selectivity with the decrease of potential in some other electroreduction reactions such as CO2 reduction.

The study aimed to reveal the different mechanisms of delaying starch digestion by ECG, EGCG and Procyanidin based on the perspective of α-amylase-flavanol interaction and starch-flavanol interaction. The interaction characteristics of flavanols with α-amylase were studied from five aspects: enzyme inhibition, kinetics, fluorescence quenching, circular dichroism (CD) and computer simulation. The IC50 of flavanols (ECG, EGCG and Procyanidin) against α-amylase were 172.21 ± 0.22, 732.15 ± 0.13 and 504.45 ± 0.19 μg/mL according to the results of α-amylase inhibition experiment, respectively. ECG and Procyanidin showed mixed inhibition against α-amylase, while EGCG showed non-competition against α-amylase. However, thermodynamic parameters，computer-based docking and dynamic simulation proved that ECG and EGCG-α-amylase complexs were mainly driven by van der Waals and hydrogen bonds, while Procyanidin-α-amylase complexs was driven by hydrophobic interaction. In addition, it was indicated, by means of starch‑iodine complex spectroscopy, that flavanols inhibited the digestion of starch not only through bind with α-amylase but also through bind with starch. Thus, flavanols as a starch-based food additive have the potential to be employed as adjuvant therapy for diabetes.

Combining GWAS, QTL-seq and transcriptome sequencing detected basal defense-related genes showing gDNA sequence variation and expression difference in diverse cotton lines, which might be the molecular mechanisms of VW resistance in G. hirsutum. Verticillium wilt (VW), which is caused by the soil-borne fungus Verticillium dahliae, is a major disease in cotton (Gossypim hirsutum) worldwide. To facilitate the understanding of the genetic basis for VW resistance in cotton, a genome-wide association study (GWAS), QTL-seq and transcriptome sequencing were performed. The GWAS of VW resistance in a panel of 120 core elite cotton accessions using the Cotton 63K Illumina Infinium SNP array identified 5 QTL from 18 significant SNPs meeting the 5% false discovery rate threshold on 5 chromosomes. All QTL identified through GWAS were found to be overlapped with previously reported QTL. By combining GWAS, QTL-seq and transcriptome sequencing, we identified eight candidate genes showing both gDNA sequence variation and expression difference between resistant and susceptible lines, most related to transcription factors (TFs), flavonoid biosynthesis and those involving in the plant basal defense and broad-spectrum disease resistance. Ten KASP markers were successfully validated in diverse cotton lines and could be deployed in marker-assisted breeding to enhance VW resistance. These results supported our inference that the gDNA sequence variation or expression difference of those genes involving in the basal defense in diverse cotton lines might be the molecular mechanisms of VW resistance in G. hirsutum.

Epigallocatechin gallate (EGCG) and epicatechin gallate (ECG) are the most abundant ester catechins of green tea polyphenols (GTPs) with numerous potential bioactivities, which have wide application prospects in the fields of medicine and functional foods. In this study, a new method using macroporous resin and crystallization was established to separate and purify EGCG and ECG. Two resins with high adsorption and desorption capacities for EGCG and ECG were screened through static adsorption/desorption tests, and the LX-20B resin was selected through column chromatography due to its best separation effect. Moreover, the column separation parameters of LX-20B resin (sample amount, ethanol elution concentration, elution volume, and elution flow rate) were optimized. After resin purification, the EGCG and ECG purity were 70.08 ± 2.55% and 74.97 ± 2.66%, respectively, and the recovery rates were 68.07 ± 2.43% and 74.28 ± 2.24%, respectively. After crystallization, the EGCG purity reached 95.87 ± 0.89%, with a total recovery rate of 58.66%, and the ECG purity reached 95.55 ± 1.30%, with a total recovery rate of 62.45%. The separation efficiency of the resin showed no significant change after 6 cycles. These results show the proposed method to be a simple, eco-friendly, and cost-effective separation method for the industrial separation and purification of EGCG and ECG from GTPs.

Separation and enrichment of phenolics from peony flowers were performed to improve the anti-biofilm and antibacterial activities for the first time. Through several times of separation, the purity of phenolics components increased significantly, and the anti-biofilm and antibacterial activities of phenolics components against E. coli and S. aureus were also significantly improved. Finally, the phenolics of peony flowers in the eluent of silica gel column chromatography (PPF-ESGCC) were found to exhibit the highest anti-biofilm and antibacterial activities. The inhibition rates of PPF-ESGCC on biofilms of E. coli and S. aureus were 77.93%, and 87.03% respectively, at a very low concentration (1/2 MIC, 0.235 mg/mL). It was found that the biofilm inhibition was achieved by inhibiting their swimming, swarming, twitching motilities, exopolysaccharide (EPS) production, and quorum sensing (QS). Moreover, there was a positive dose-dependent relationship (r = 0.75 to 1) between the inhibition rates and concentrations of PPF-ESGCC during the critical biofilm-formation stage (1-3 days). Chemical composition analysis showed the PPF-ESGCC comprised of gallic acid, kaempferol-7-O-glucoside, and apigenin-7-O-glucoside. In conclusion, PPF-ESGCC exhibited strong inhibitory effect on biofilm formation and gallic acid, kaempferol-7-O-glucoside, and apigenin-7-O-glucoside might play a crucial role in inhibiting biofilm formation. Meanwhile, this study indicated that PPF-ESGCC, a new natural QS inhibitor and biofilm inhibitor, could be used as a novel intervention strategy to enhance the safety and quality of food.

This study sought to develop a nanoscale delivery system to enhance the stability and bioaccessibility of goat milk whey protein peptides. Goat milk whey protein was hydrolyzed by papain, and the hydrolysate was ultrafiltered to obtain a low molecular weight peptide (GWP,3 kDa) with strong hypoglycemic activity. The GWP-loaded liposomes and niosomes encapsulation systems were prepared using phytosterols (ergosterol, β-sitosterol, mixed phytosterols, and stigmasterol) instead of cholesterol. Results showed that the GWP-loaded niosomes (GWP-NS) prepared from β-sitosterol had the higher GWP encapsulation efficiency (90.46 ± 4.02 %) and the smaller particle size (92.07 ± 9.8 nm) than liposomes (GWP-LS). Additionally, the morphological results showed that two GWP-loaded systems were smooth and spherical, and the FT-IR spectroscopy confirmed the successful formation of the peptide-loaded system. Compared with GWP, GWP-LS and GWP-NS showed the higher stability under different pH, temperature, and NaCl concentration conditions, especially GWP-NS. Furthermore, GWP-NS could significantly improve the retention rate of GWP during simulated gastrointestinal digestion, in vitro bioaccessibility, and hypoglycemic activity. These findings suggest that β-sitosterol could be a potential membrane stabilizer alternative to cholesterol, and GWP niosomes could be a potential new drug delivery system.

Oxygen activation, including oxygen reduction reaction (ORR) and oxygen evolution reaction (OER), is at the heart of many important energy conversion processes. However, the activation mechanism of Ba-containing perovskite materials is still ambiguous, because of the complex four-electron transfer process on the gas-solid interfaces. Here, we directly observe that BaO and BaO 2 segregated on Ba-containing material surface participate in the oxygen activation process via the formation and decomposition of BaO 2 . Tens of times of increase in catalytic activities was achieved by introducing barium oxides in the traditional perovskite and inert Au electrodes, indicating that barium oxides are critical for oxygen activation. We find that BaO and BaO 2 are more active than the B-site of perovskite for ORR and OER, respectively, and closely related to the high activity of Ba-containing perovskite.

A precursor-engineering strategy coupled with a microwave molten-salt process (PE-MWMS) is developed to synthesize graphitic carbon nitride (g-C3 N4 ) with an isotype triazine/heptazine-based g-C3 N4 heterojunction as a photocatalyst for the hydrogen evolution reaction (HER) under visible light illumination. Four hybrid precursor combinations-thiourea/melamine, thiourea/dicyandiamide, urea/melamine, and urea/dicyandiamide-are used to synthesize g-C3 N4 heterojunctions by the PE-MWMS process. Control experiments indicate that the precursor components and microwave treatment have a great effect on the HER performance of the g-C3 N4 samples. Samples synthesized with the optimal molar ratios of thiourea/melamine (2:1), thiourea/dicyandiamide (2:1), urea/melamine (3:1), and urea/dicyandiamide (3:1), exhibit the highest HER rates of 3135, 2519, 2844, and 2565 μmol g-1 h-1 , respectively. The amounts of heptazine and triazine units in the g-C3 N4 samples can be easily adjusted by changing the ratios of the hybrid precursors and play a decisive role in improving the photocatalytic HER activity. Because of the unique composition and microstructure, the efficient separation of electron-hole pairs, the broadened photo-absorption edges, and the narrowed band gaps, the as-obtained triazine/heptazine-based g-C3 N4 nanostructures exhibit promising activity for HER application.

Building architectures to manipulate light propagation using a light-conversion matrix is one of the most competitive strategies to enhance photocatalytic performance. In this work, a bio-inspired SiO2 hard template with interconnected SiO2 with a one-dimensional structure was devised to enhance the visible light harvesting ability of g-C3N4, and the SiO2/g-C3N4 nanocomposite is cleverly synthesized via an in situ thermal polymerization method. Based on UV-vis diffuse reflectance spectrometry (UV-vis DRS) and finite difference time domain simulation (FDTD) measurements, it is found that the SiO2/g-C3N4 nanocomposite displays obviously enhanced visible light absorption and light-scattering when compared to pristine g-C3N4, suggesting it has highly enhanced light harvesting ability. As expected, SiO2/g-C3N4 displays a remarkable enhancement in photocatalytic H2 production when compared to bare g-C3N4. Such enhancement is attributed to the synergistic effect of g-C3N4 and SiO2 hard template microstructures. The SiO2 one-dimensional structure not only enhances light scattering to widen the visible-light absorption range and improve the utilization efficiency of solar energy, but it also increases the specific surface area of g-C3N4 by reducing its aperture size. This research has far-reaching implications for increasing the use of sunlight and improving the development of hydrogen energy.

In the present study, microwave-assisted extraction (MAE), ultrasound-microwave synergistic extraction (UMSE) and conventional liquid–solid extraction (CLSE) methods were performed to extract the phenolics from ground peony flowers. For MAE and UMSE, the effect of extraction conditions (microwave power, extraction time, solid/solvent ratio, ethanol concentration) on the yield of phenolics was evaluated. Optimum conditions were determined in experiments where a single factor was varied. Under optimal conditions, yield, purity, composition, antioxidant and antimicrobial activities of the phenolics from the different extracts were analyzed. The antioxidant activities were determined using 2,2-diphenyl-1-picrylhydrazyl (DPPH), 2,2′-azino-bis-3-ethylbenzthiazoline-6-sulphonic acid (ABTS) and reducing power assays. Thus, the half-maximal inhibitory concentration (IC50) was defined for the different extraction procedures in both DPPH and ABTS assays. The antimicrobial activities of the extracts were determined using an agar well diffusion assay. Although CLSE extracts exhibited the strongest free radical scavenging activities for both ABTS (IC50 = 11.35 ± 0.36 μg/mL) and DPPH (IC50 = 18.07 ± 0.21 μg/mL), and displayed the greatest reducing power, they also had the weakest inhibitory activities for all tested bacteria. Conversely, MAE extracts exhibited the largest zone of inhibition for Escherichia coli (E. coli) (14.00 ± 1.00 mm), Streptococcus mutans (S. mutan) (13.75 ± 0.50 mm), and Streptococcus agalactiae (S. agalactiae) (12.00 ± 0.10 mm), indicating that MAE extracts exerted the best antimicrobial activities. Therefore, the CLSE method should be selected for producing the strongest antioxidant activities and the MAE procedure for generating the strongest antimicrobial activities.

Epigallocatechin gallate (EGCG) has a variety of biological activities, but exhibits poor stability and low bioavailability. In this study, EGCG bilosome was prepared and characterized, and its stability during different storage conditions (pH, NaCl concentration, and temperature) and in gastrointestinal fluid was evaluated and compared with liposomes and niosomes. Among them, EGCG niosomes had the highest pH stability, and the existence of sodium cholate reduced the stability of bilosomes in acidic medium. EGCG stability was significantly increased in the presence of salt ions (0–100 mM NaCl) and under different temperatures (25 °C, 37 °C) when delivered as niosomes and bilosomes. Retention rate of EGCG in bilosomes was 71.64 ± 4.05% after incubation in simulated intestinal fluid for 2 h, which was significantly higher than retention rate of EGCG liposomes (24.02 ± 3.95%) and niosomes (55.74 ± 6.85%), thus indicating greater gastrointestinal stability of EGCG bilosomes. Furthermore, bioavailability of EGCG encapsulated in bilosomes was improved by 1.98 times. Overall, these findings indicate that EGCG bilosomes, as a new delivery system, had great potential application as a means to improve stability and bioavailability of EGCG.

There is a growing interest in screening α-amylase inhibitors from natural products for application in the development of new antidiabetic drugs or functional foods. In this study, a structure-based virtual screening was applied to rapidly identify the α-amylase inhibitors from medicine food homology (MFH) plants. Similarity search, docking & scoring were used for further filter small molecules. As a result, 21 corresponding potential α-amylase inhibitors from MFH plants were obtained. And, six polyphenol compounds (curcumin, procyanidins, epicatechin gallate (ECG), epigallocatechin gallate (EGCG), hesperidin, and puerarin) were highlighted for further verification after a thorough assessment of the classification of hit molecules as well as docking scores. The results of the enzyme inhibition test showed that ECG, EGCG, and procyanidins had the better binding ability of α-amylase among these six polyphenols. The Ki values of ECG, EGCG, and procyanidins on α-amylase were 0.70, 1.68, and 0.24, respectively. The CD spectra results indicated that the three polyphenols can cause conformational changes in α-amylase. PRACTICAL APPLICATIONS: A structure-based virtual screening method for rapid identifying α-amylase inhibitors from MFH plants was developed successfully in this study. These findings suggested that natural polyphenols such as ECG, EGCG, and procyanidins may be a potential inhibitor of α-amylase which could be used as a nutrient supplement for the prevention of diabetes mellitus or can be further used in the development of hypoglycemic drugs. At the same time, it can provide theoretical guidance for the better utilization and development of medicine food homology plants containing these potential α-amylase inhibitors. Moreover, this work may provide ideas and references for the screening of other target protein inhibitors.

The material class of hybrid organic–inorganic halide perovskites has been rapidly progressed in the field of photovoltaic applications. However, this class of materials has limitations associated with its poor stability and toxicity of the lead element. Therefore, there is a strong desire to search for environmentally friendly perovskite materials without affecting the conversion efficiency. First-principles calculations have been employed to study thermodynamic stability, electronic, and optical properties of potential candidate lead-free perovskites. The results show that the ionization energy at the A-site can provide an explanation for the stabilities of hybrid perovskites. The bond lengths and bond angles are likely responsible for the discrepancy in the band gap. The results indicate that DAGeI3 has better stability and suitable band gap among Ge-based AGeI3 perovskites. It is observed that the Si-doped perovskites are energetically favorable. CsGe2/3Si1/3I3 can become the potential candidate for t...

The proposal of pseudocapacitive materials breaks the barriers between batteries and capacitors, allowing for the possible achievement of a balanced energy-power performance. However, the limited reserve of lithium restricts the practical applications of pseudocapacitive materials in lithium-based systems, whereas sodium resources are abundant with the similar properties to lithium, but there is a lack of suitable pseudocapacitive materials for sodium-based systems. The exploitation of pseudocapacitive materials for Na+ storage is urgent. This study, for the first time, reports a sonochemical approach, involving intercalation and ultrasonic exfoliation processes, to prepare composite K2Mo4O13/α-MoO3 (i.e., KMO) nanorods, and the possible applications of the KMO nanorods in Li+/Na+ pseudocapacitance were evaluated. The as-synthesized KMO possessed a uniform rod-like morphology formed by assembling nanoneedles (or nanobelts) with a large apparent aspect ratio of more than 10. Both in lithium ion batteries (LIBs) and sodium ion batteries (SIBs), the KMO nanorods exhibited efficient pseudocapacitance, which was not observed in the pristine MoO3–Na system. In SIBs, the as-synthesized KMO delivered a capacity of 895 mA h g−1 at 0.02 A g−1, which was much higher than that of the pristine MoO3–Na system. Moreover, it was found that the b values of KMO (i = avb, current i and scan rate v in the CV curves) were over 0.9 at potentials ranging from 1 V to 2 V in SIBs, indicating an obvious pseudocapacitive process. Benefiting from the layered K2Mo4O13 nanorods built with edge-shared distorted MoO6 octahedra, the Na+ ions with a larger size could be intercalated into the spaces between the double MoO6 plates. This sonochemical approach based on the intercalation and exfoliation chemistry opened a new path to prepare molybdenum-based nanostructures for superior Li+/Na+ pseudocapacitance applications on a large scale in a low-carbon and environment-friendly manner.

Hybrid organic–inorganic halide perovskite solar cells have recently attracted much attention because of their highly efficient photovoltaic performance. However, perovskite solar cells suffer from intrinsic instabilities, which limit their commercial applications. In this study, we partially substituted the methyl-ammonium (MA) cation in MA lead iodide perovskite (MAPbI3) and investigated the geometric structures and electronic and optical properties by first-principles calculations to determine their thermodynamic stabilities and optical band gaps. The results suggest that substitution of the Az cation in the A-site can enhance the stability of the MA1−xAzxPbI3 system. However, the formation energies indicate that the MA1−xCyxPbI3 series is less stable. The estimated power conversion efficiency of MA0.50Az0.50PbI3 is 23.06%, which is higher than that of MAPbI3. Notably, MA1−xAzxPbI3 (0.50 < x < 0.75) is predicted to be a promising candidate for photovoltaic applications because it has the highest theoretical power conversion efficiency, which is attributed to its optimal band gap. These results suggest that an organic cation mixing strategy can be used to tune the stability, band gap, and photovoltaic performance of hybrid perovskites, which will be particularly useful for designing light-harvesting materials for perovskite solar cells.

To reduce the toxicity of Pb in perovskite solar cells, the structural stabilities, electronic and optical properties of the mixed perovskites MAPb0.75B0.25I3 (B = Mg, Ca, Sr, and Ba) were predicted using density functional theory. The calculated results show that the introduction of alkaline-earth metal components caused the structural stabilities of the mixed perovskites to weaken compared to that of MAPbI3. Moreover, the bandgaps of metal-doped perovskites are larger than that of MAPbI3. The results indicate that the bandgaps of the mixed perovskites are mainly determined by the Pb–I–B bond angles in the ab plane. The optical absorption coefficients of all of the metal-doped perovskites significantly decrease due to the use of alkaline-earth metals. These results provide a deep insight into a new kind of lead-free perovskite.

Perovskite photovoltaic materials are gaining significant attention due to their excellent photovoltaic properties. In this study, density functional theory calculations were performed to investigate the structure and electronic and optical properties of CsGeI3 under hydrostatic strain. The results show that the band gap of CsGeI3 can be tuned from 0.73 eV to 2.30 eV under different strain conditions. The results indicate that the change in the band gap under strain is likely to be determined by the Ge–I–Ge bond angle. Interestingly, the length of the short Ge–I bond remains unchanged, whereas that of the long Ge–I bond exhibits an evident increment with strain ranging from −4% to 4%. A suitable band gap (1.36 eV) of CsGeI3 can be obtained under a strain of −1%. Both the calculated elastic constants and the phonon spectrum imply that this structure is stable under the abovementioned condition. Bandgap narrowing induces a red shift of the light absorption spectrum of CsGeI3 by extending the onset light absorption edge. These results are important for understanding the effects of strain on the halide perovskites and guiding the experiments to improve the photovoltaic performance of the perovskite solar cells.

This study aimed to reveal the interaction and inhibitory mechanisms of tangeretin (TAN), nobiletin (NBT), and their acidic hydroxylated forms, 5-demethyltangeretin (5-DT) and 5-demethylnobiletin (5-DN) on porcine pancreatic lipase (PPL) using spectroscopic techniques and molecular dynamics (MD) simulation. PPL inhibition assay showed that the inhibitory activity of NBT (IC50 value of 3.60 ± 0.19 μM) was superior to those of three polymethoxylated flavones (PMFs), indicating it may be related to the methoxy groups at the 3′-position in its molecular structure. Inhibition kinetic analyses demonstrated that the inhibition types of the 4 PMFs were consistent with the mixed inhibition model, which agreed well with the results from the ultraviolet-visible (UV–Vis) spectroscopy, Circular dichroism (CD), fluorescence spectroscopy, molecular docking, and MD simulation that PMFs could bind to the PPL catalytic site and non-catalytic site, affecting the normal spatial conformation of PPL and weakening its ability to decompose the substrate. All these findings suggest that PMFs are a kind of natural lipase inhibitors, and NBT has the potential as a lipase inhibition precursor because of its unique flavone skeleton structure.

In this work, a novel synthesis strategy of sodium alginate/carboxymethyl chitosan hydrogel beads promoted by hydrogen bond was described. The beads were prepared by dropping the blends of two polymers into the citric acid solution. Besides hydrogen bonding, electrostatic interactions were also involved in the formation of the hydrogel beads. The thermal stability experiments revealed that the more the content of carboxymethyl chitosan, the better the thermal stability of the beads. The beads exhibited excellent pH sensitivity, pH reversibility, and lactoferrin loading capacity. The swelling ratio of the bead and its protein releasing profile was pH-dependent, which could prevent premature protein release in the gastric environment. Also, the circular dichroism results demonstrated that lactoferrin could maintain its structure during the loading and releasing process. The obtained results revealed that the hydrogel beads prepared in this work could be used as a potential protein carrier for oral delivery.

The reverse water gas shift (RWGS) reaction has attracted great attention in recent years. It is well-known that supported catalysts, especially single-atom catalysts (SACs), exhibit good catalytic activity in many reactions. Thus, we designed the single-atom catalyst (SAC) Cu@Mo2C(001) and the smallest copper cluster catalyst Cu4@Mo2C(001) for the RWGS reaction. In this study, density functional theory (DFT) calculations were used to explore the reaction mechanisms of the RWGS reaction on the surfaces of Cu@Mo2C(001) and Cu4@Mo2C(001). The dissociative adsorption of H2 on these two surfaces is barrier-free and highly exothermic, which is beneficial to the RWGS reaction. Importantly, three possible mechanisms—the COOH mechanism, HCOO mechanism, and redox mechanism—have been discussed. The results illustrated that the redox mechanism is the most feasible pathway among the Cu@Mo2C(001) and Cu4@Mo2C(001) surfaces. By comparing the activation barrier of the rate-limiting step of the redox mechanism on the two...

The exploration and improvement of excellent mid-infrared nonlinear optical (NLO) materials is still in great demand. The perovskite-type Sr2Nb2O7 is found to be a good predictor of NLO properties due to the similar band gap and NLO coefficients to KTiOPO4 (KTP). In this paper, we systematically investigated the electronic structures, linear and nonlinear properties of pure and V-doped Sr2Nb2O7 based on DFT. It is found that the V-doped Sr2Nb2O7 doubles the NLO coefficient and exhibits higher birefringence, which is moderate and sufficient for phase-matching. The results are helpful to the further development of the mid-infrared NLO crystals with perovskite structure.

The selenium polysaccharides (SPS) by Oudemansiella radicata were isolated, and two hydrolysates (enzymatic-SPS (ESPS) and acidic-SPS (ASPS)) were obtained by enzymolysis and acidolysis. The endo-toxemic-induced lung and kidney damages were successfully established by the lipopolysaccharides (LPS) injection (5 mg/kg/d). The in vivo mice experiments indicated that the ESPS showed superior antioxidant and protective effects against the LPS-toxicities by increasing the antioxidant activities, reducing lipid peroxidation, improving the inflammatory response and elevating the kidney and lung functions than SPS and ASPS. Furthermore, the selenium contents and structure of SPS, ESPS and ASPS were investigated through FAAS, GC, UV, HPGPC, FT-IR, NMR and the results indicated that SPS, ESPS and ASPS were homogeneous heteropolysaccharide with an average molecular weight of 3.12 × 104, 1.77 × 104, 1.41 × 104 Da, respectively. The conclusions demonstrated that the polysaccharides by O. radicata might be suitable for functional foods and natural drugs in preventing the endo-toxemia and its complications, and providing references for exploitation and utilization of natural substances.

In present study, the soluble polysaccharides by enzyme-assisted extraction from Agaricus bisporus (EnAPS) and its purified fractions of EnAPS-1, -2 and -3 were successfully obtained, and the antioxidant activities and anti-aging effects were investigated. The in vitro antioxidant assay demonstrated that EnAPS-2 had superior scavenging activities on DPPH and hydroxyl radicals, chelating activities of Fe2+ and reducing power. The in vivo animal experiments showed that both EnAPS and its purifies fractions had potential anti-aging effects against the d-galctose-induced aging diseases on liver, kidney, brain and skin, possibly by increasing the antioxidant enzymes, reducing the lipid peroxidation, improving the organ functions and remitting the lipid metabolism. The conclusions demonstrated that the polysaccharides by A. bisporus might be suitable for applying functional foods and natural drugs in preventing and delaying the aging and its complications.

The present work investigated the characteristics, antioxidative, anti-inflammative and renoprotective effects of mycelia selenized polysaccharides (MSPS) from Oudemansiella radicata on lipopolysaccharide (LPS)-induced kidney damaged mice. The results demonstrated that both MSPS and mycelia polysaccharides (MPS) showed potential renoprotective effects reflecting by decreasing the serum levels of CRE, BUN and UA, increasing the nephritic enzyme activities of SOD, GSH-Px, CAT and T-AOC, reducing the activities of MPO, as well as down-regulating the contents of MDA and LPO, respectively. And the MSPS showed superior effects. Furthermore, the selenium contents and physical properties of polysaccharides were investigated by FAAS, GC, HPGPC, FT-IR, NMR and AFM analysis, and the results indicated that MSPS was a homogeneous heteropolysaccharide with an average molecular weight of 3.12 × 104 Da. These results may provide theoretical basis in applying natural and functional foods for the prevention and alleviation of kidney damages and its complications.

Owing to the high theoretical photocurrent density, the hematite (α-Fe2O3) based photoanode has been intensively concerned in photoelectrochemical (PEC) water splitting, but its serious charge recombination and sluggish water oxidation kinetics are still the stumbling blocks. This work reports a high-performance Fe2O3-based photoanode achieved by coating multifunctional FeCo-bimetal organic framework (MOF) nanolayers (NLs) on Fe2O3 nanoarrays via an in-situ solvothermal process. The FeCo MOF NLs introduced not only effectively passivate the surface states of Fe2O3 photoanode and boost the water oxidation kinetics serving as the cocatalyst, but also construct p-n heterojunctions with Fe2O3 to accelerate the directional migration and separation of photogenerated charge carriers. Expectedly, the as-obtained FeCo-MOF/Fe2O3 photoanode exhibits an apparent negative shift of onset potential, an excellent long-term PEC stability, and highly improved photocurrent density. This finding provides a novel and effective strategy to introduce advanced multifunctional surface coating for enhancing the PEC performance of photoelectrodes.

In present study, two hydrolyzed residue polysaccharides (RPS) of enzymatic-RPS (ERPS) and acidic-RPS (ARPS) were successfully obtained from the residue of Lentinula edodes , and the anti-inflammatory as well as antioxidative effects on lipopolysaccharide-induced (LPS-induced) lung injured mice were investigated. The results demonstrated that ERPS showed superior lung protective effects by ameliorating the lung wet-to-dry weight (W/D) ratio, reducing the TNF-α, IL-6, and IL-1β levels in BALF, lowing the pulmonary MPO activity, decreasing the serum C3 and hs-CPR contents, as well as improving the antioxidant status by enhancing pulmonary enzyme activities (SOD, GSH-Px, CAT, and T-AOC) and eliminating the lipid peroxidation (MDA and LPO), respectively. These conclusions indicated that both RPS and its hydrolysates (ARPS and ERPS) might be suitable for functional foods and a potentially effective candidate medicine for the treatment of lung injury.

This study was designed to investigate the antioxidant and anti-aging effects of D-galatose-induced (D-gal-induced) aging mice as well as monosaccharide compositions of acidic-extractable polysaccharides (AcAPS) and its major purified fractions (AcAPS-1, AcAPS-2 and AcAPS-3) from the fruiting body of Agaricus bisporus. In the in vitro assays, AcAPS-2 showed superior scavenging activities on hydroxyl (82.98±4.67%) and DPPH (64.47±4.05%) radicals at the concentration of 1.0mg/mL than AcAPS and other polysaccharides fractions. For in vivo anti-aging analysis, AcAPS-2 showed superior effects on hepatic and nephric protection by improving serum enzyme activities, biochemical levels, lipid contents and antioxidant status, respectively. The monosaccharide analysis showed that rhamnose (Rha) and glucose (Glu) may play vital roles in maintaining the antioxidant and anti-aging activities. The results suggested that both AcAPS and its purified fractions might be suitable for functional foods and natural drugs in preventing the acute aging-associated diseases.

This paper reports a novel hybridization of heterogeneous atoms to regulate the photocatalytic behavior of graphitic carbon nitride (g-C3N4) by controlling its energy band structure. The K+-modified g-C3N4 (KCN) was obtained by KCl/LiCl molten-salt treating the urea-derived pristine g-C3N4 (CN), and the H+-modified g-C3N4 (HCN) was obtained by HCl-treating KCN. The photocatalytic hydrogen evolution reaction (HER) and gaseous acetaldehyde degradation (GAD) results show that KCN exhibits a high HER rate of 3447 μmol h−1 g−1, up to 19 times that of CN, whereas HCN has the GAD reaction rate constants of 0.876 and 4.352 h−1 under visible light and simulated solar light, respectively. The difference in photocatalytic HER and GAD resulted from the stronger reducibility of KCN and higher oxidizability of HCN, because of the efficient regulation in their energy band structures modified with K+ and H+.