Unusual, hierarchically structured composite of sugarcane pulp bagasse biochar loaded with Cu/Ni bimetallic nanoparticles for dye removal.

Biochar-supported nanocatalysts emerged as unique materials for environmental remediation. Herein, sugarcane pulp bagasse (SCPB) was wet-impregnated with Cu(NO3)23H2O and Ni(NO3)26H2O, then pyrolyzed at 500 °C, under N2, for 1 h. We specifically focused on sugarcane pulp instead of SCB and biochar materials. The metal nitrate to biomass ratio was set at 0.5, 1, and 2 mmol/g, with Cu/Ni initial ratio = 1. The process provided hierarchically structured porous biochar, topped with evenly dispersed 40 nm-sized CuNi alloy nanoparticles (SCPBB@CuNi). The biochar exhibited an unusual fishing net-like structure induced by nickel, with slits having a length in the 3-12 µm range. Such a fishing net-like porous structure was obtained without any harsh acidic or basic treatment of the biomass. It was induced, during pyrolysis, by the nanocatalysts or their precursors. The CuNi nanoparticles form true alloy as proved by XRD, and are prone to agglomeration at high initial metal nitrate concentration (2 mmol/g). Stepwise metal loading was probed by XPS versus the initial metal nitrate concentration. This is also reflected in the thermal gravimetric analyses. The SCPBB@CuNi/H2O2 (catalyst dose: 0.25 g/L) system served for the catalyzed removal of Malachite Green (MG), Methylene Blue (MB), and Methyl Orange (MO) dyes (concentration = 0.01 mmol/L). Both single and mixed dye solutions were treated in this advanced oxidation process (AOP). The dyes were removed in less than 30 min for MG and 3 h for MB, respectively, but 8 h for MO, therefore showing selectivity for the degradation of MG, under optimized degradation conditions. The catalysts could be collected with a magnet and reused three times, without any significant loss of activity (∼85%). AOP conditions did not induce any nanocatalyst leaching. To sum up, we provide a simple wet impregnation route that permitted to design highly active Fenton-like biochar@CuNi composite catalyst for the degradation of organic pollutants, under daylight conditions.

Lactocaseibacillus rhamnosus zz-1 Supplementation Mitigates Depression-Like Symptoms in Chronic Stress-Induced Depressed Mice via the Microbiota-Gut-Brain Axis.

Accumulating evidence has revealed an association between depression and disordered intestinal microecology. The discovery of psychobiotics has provided a promising perspective for studying the treatment of psychiatric disorders. Here, we aimed to investigate the antidepressant abilities of Lactocaseibacillus rhamnosus zz-1 (LRzz-1) and elucidate the underlying mechanisms. The viable bacteria (2 × 109 CFU/day) were orally supplemented to depressed C57BL/6 mice induced by chronic unpredictable mild stress (CUMS), and the behavioral, neurophysiological, and intestinal microbial effects were assessed, with fluoxetine used as a positive control. The treatment with LRzz-1 effectively mitigated the depression-like behavioral disorders of depressed mice and reduced the expression of inflammatory cytokine mRNA (IL-1ß, IL-6, and TNF-α) in the hippocampus. In addition, LRzz-1 treatment also improved tryptophan metabolic disorder in the mouse hippocampus, as well as its peripheral circulation. These benefits are associated with the mediation of microbiome-gut-brain bidirectional communication. CUMS-induced depression impaired the intestinal barrier integrity and microbial homeostasis in mice, neither of which was restored by fluoxetine. LRzz-1 prevented intestinal leakage and significantly ameliorated epithelial barrier permeability by up-regulating tight-junction proteins (including ZO-1, occludin, and claudin-1). In particular, LRzz-1 improved the microecological balance by normalizing the threatened bacteria (e.g., Bacteroides and Desulfovibrio), exerting beneficial regulation (e.g., Ruminiclostridium 6 and Alispites), and modifying short-chain fatty acid metabolism. In summary, LRzz-1 showed considerable antidepressant-like effects and exhibited more comprehensive intestinal microecological regulation than other drugs, which offers novel insights that can facilitate the development of depression therapeutic strategies.

Self-Adhesive and Conductive Dual-Network Polyacrylamide Hydrogels Reinforced by Aminated Lignin, Dopamine, and Biomass Carbon Aerogel for Ultrasensitive Pressure Sensor.

Conductive hydrogels have attracted extensive interest owing to its potential in soft robotics, electronic skin, and human monitoring. However, insufficient mechanical properties, lower adhesivity, and unsatisfactory conductivity seriously hinder potential applications in this emerging field. Herein, a highly elastic conductive hydrogel with a combination of favorable mechanical properties, self-adhesiveness, and excellent electrical performance was achieved by the synergistic effect of aminated lignin (AL), polydopamine (PDA), polyacrylamide (PAM) chains, and biomass carbon aerogel (C-SPF). In detail, AL was applied to induce slow oxidative polymerization of DA for preparing the sticky hydrogel containing PDA. Then, C-SPF carbon aerogel was used as a matrix to construct a dual-network structured composite hydrogel by combining with the hydrogels derived from PDA, AL, and PAM. The as-prepared conductive hydrogel displayed excellent mechanical performance, strong adhesive strength, and repeatable adhesivity. The prepared hydrogel-based pressure sensor possessed fast response (0.6 s loading and 0.8 s unloading stress time), high response (maximum RCR = 1.8 × 104), wide working pressure range (from 0 to 240.0 kPa), and excellent durability (stable 500 compression cycles with 30% deformation). In addition, the prepared sensor also displayed ultrahigh sensitivity (170 kPa-1), which was near 4 orders of magnitude higher than the conventional lignin-modified PAM hydrogels. The multiple interactions between hydrogel components and the mechanical properties of hydrogel were also verified by molecular dynamics investigation. Moreover, the excellent cytocompatibility and antibacterial activity of this composite hydrogel ensured high potential in various applications such as human/machine interaction, artificial intelligence, personal healthcare, and wearable devices.

Solution-phase controlled synthesis of Cu3NbSe4 nanocrystals for optoelectronic applications.

Cu3MX4 (M = V, Nb, and Ta; X = S, Se, and Te) compounds have recently emerged as greatly promising solar energy conversion materials due to their tailorable band gaps, high optical absorption coefficients, environmentally benign nature and comparatively abundant elements. However, solution synthesis of Cu3NbSe4 nanocrystals as a photoactive material for investigating their optoelectronic properties has not yet been reported. Herein, we present a facile synthesis of cube-shaped Cu3NbSe4 nanocrystals with high crystallinity, high uniformity and monodispersity. Studies of the formation process disclose that the reaction temperature, time and surface ligand play significant roles in determining the crystalline phase, size and morphology evolution of the Cu3NbSe4 nanocrystals. Excitingly, a Cu3NbSe4-based photodetector exhibits a high Ilight/Idark ratio of 35, fast response speeds of 0.3/0.1 s for rise/fall times and excellent stability, indicating its robust potential for application in electronics and optoelectronics.

Novel solution synthesis of the overlooked cubic phase Cu2GeTe3 nanocrystals for optoelectronic devices.

Herein, for the first time, we present a novel solution method for controllable synthesis of the overlooked cubic phase Cu2GeTe3 nanocrystals. The resulting Cu2GeTe3 nanocrystals are of high quality with monodispersed size and uniform shape. Optical characterization demonstrates that Cu2GeTe3 nanocrystals have a broad absorption in the visible to near-infrared region. Furthermore, an optoelectronic device based on Cu2GeTe3 nanocrystals exhibits excellent stability, reproducibility and responsivity. The novel synthetic route presented here not only can open a new avenue for fabricating Cu2GeTe3 nanocrystals, especially at the nanoscale, but also may further expand their applications.

Lactobacillus rhamnosus zz-1 exerts preventive effects on chronic unpredictable mild stress-induced depression in mice via regulating the intestinal microenvironment.

Depression remains one of the most prevalent psychiatric disorders, and it has been confirmed that it is related to the dysfunction of the microbiota-gut-brain axis. Manipulation of the gut microenvironment by probiotics might improve mental health and prevent stress-related psychiatric disorders. The present study aimed to determine whether Lactobacillus rhamnosus (L. rhamnosus) zz-1 could prevent the occurrence of depression and its potential mechanisms using a mouse model with chronic unpredictable mild stress (CUMS). The results indicated that L. rhamnosus zz-1 intervention ameliorated CUMS-induced depression-like behaviors of mice with reduced body growth rate, lowered sucrose preference, increased immobility time, as well as decreased curiosity and mobility. Moreover, L. rhamnosus zz-1 significantly inhibited hormones released due to hyperactivity of the hypothalamic-pituitary-adrenal (HPA) axis, alleviated CUMS-induced deficits of monoamine neurotransmitters, and increased the expression of brain-derived neurotrophic factor (BDNF) and tyrosine kinase receptor B (TrkB). These benefits were partially linked to the regulation of the intestinal microenvironment. L. rhamnosus zz-1 alleviated intestinal damage and reduced intestinal inflammation of the depressed mice. Meanwhile, L. rhamnosus zz-1 effectively adjusted the dysbiosis of mouse gut microbiota induced by CUMS, such as changes in the abundance of the Lachnospiraceae NK4A136 group, Bacteroides, and Muribaculum. Taken together, these results demonstrated that L. rhamnosus zz-1 was effective in preventing depression from chronic stress, adding new evidence to support the mental benefits of probiotics.

Zein enhanced the digestive stability of five citrus flavonoids via different binding interaction.

BACKGROUND: Zein is commonly used to construct food flavonoid delivery systems. This study investigated the effect and mechanism of zein on the digestive stability of five citrus flavonoids, namely hesperetin (HET), hesperidin (HED), neohesperidin (NHD), naringenin (NEN), and naringin (NIN). RESULTS: Zein enhanced the digestive stability of the five citrus flavonoids, especially that of HET and NEN, during digestion in the stomach and small intestine. Fluorescence spectroscopy results suggested that citrus flavonoids spontaneously quenched the endogenous fluorescence of zein in static quenching mode. The binding of HET, HED and NHD to zein was driven respectively by electrostatic, hydrophobic and electrostatic interaction. However, Van der Waals' force and hydrogen (H)-bond interaction represented the primary driving force for binding NEN, and NIN to zein to form complexes. The binding of the five citrus flavonoids to zein also caused a diverse bathochromic shift in ultraviolet absorbance. Analysis using Fourier-transform infrared and Raman spectroscopy revealed that the binding behavior of the five citrus flavonoids had different effects on changes in the secondary structures, disulfide bonds, and tyrosine exposure of zein. The results were also partially verified by molecular dynamic simulation. CONCLUSIONS: Zein enhanced the digestive stability of the five citrus flavonoids via different binding interactions that was due to the difference in molecular structure of citrus flavonoids. © 2022 Society of Chemical Industry.

Ultrahigh compressibility and superior elasticity carbon framework derived from shaddock peel for high-performance pressure sensing.

Shaddock peel, a crop by-product mainly composed of cellulose, hemicellulose, lignin, and pectin, was developed as a flexible sensitive material for detecting environmental external pressure. Firstly, a natural carbon framework (C-SPF) with high conductivity was prepared using hydrothermal treatment followed by carbonization. Then, the PDMS elastomer was coated on the C-SPF instead of dense filling to convert the brittle C-SPF into elastic porous materials (M-SPF). Benefiting from the large deformation space of the porous framework and the stable interactions between PDMS and C-SPF, M-SPF exhibited ultrahigh coercibility (up to 99.0% strain) and high elasticity (99.4% height retention for 10 000 cycles at 50.0% strain). The M-SPF-based pressure sensor also exhibited a quick response (loading and unloading times were 20 ms and 30 ms), high sensitivity (63.4 kPa-1), wide working range (from 0 to 800 kPa), and stable stress-electric current response (10 000 cycles). These advantages open a door to a variety of applications, such as flexible wearable devices, which demonstrated human physiological signal monitoring. The low cost, simple design and portable use of piezoresistive sensors highlight the potential application of the crop by-product shaddock peel as a high-value material.

Effects of dietary rumen-protected Lys levels on rumen fermentation and bacterial community composition in Holstein heifers.

This study aimed to evaluate the effects of partial reducing rumen-protected Lys (RPLys) on rumen fermentation and microbial composition in heifers. Three ruminal fistulated Holstein Friesian bulls were used to determine the effective degradability of RPLys using an in situ method at incubation times of 0, 2, 6, 12, 16, 24, 36, and 48 h. Thereafter, 36 Holstein heifers at 90 days of age were assigned to one of two dietary treatments: a theoretically balanced amino acid diet (PC group; 1.21% Lys, 0.4% Met) or a 30% Lys-reduced diet (PCLys group, 0.85% Lys, 0.4% Met). Rumen fluid samples from five heifers in each group were extracted using esophageal tubing on day 90 to determine pH, microprotein, ammonia, volatile fatty acids, and microbial communities. Results showed that the effective ruminal degradability was 25.76%. Furthermore, differences in rumen fermentation parameters and alpha diversity of the microbiota between the two groups were not significant, but beta diversity was significant. Based upon relative abundance analysis, short-chain fatty acid-producing bacteria, including Sharpea, Syntrophococcus, [Ruminococcus]_gauvreauii_group, Acetitomaculum, and [Eubacterium]_nadotum_group belonging to Firmicutes, were significantly decreased in the PCLys group. Spearman's analysis revealed a positive correlation between the butyrate molar proportion and the relative abundance of butyrate-producing bacteria such as [Eubacterium]_nadotum_group, Coprococcus_1, Ruminococcaceae_UCG_013, Pseudoramibacter, and Lachnospiraceae_UCG_010. Phylogenetic Investigation of Communities by Reconstruction of Unobserved States analysis further validated that RPLys deduction influenced energy metabolism. Together, our findings highlight the role of RPLys or Lys in butyrate-producing bacteria. However, the number of bacteria affected by Lys was very limited and insufficient to alter rumen fermentation. Key Points • Reducing 30% Lys via rumen-protected Lys did not affect rumen fermentation parameters and alpha diversity of microbiota of Holstein heifers. It meant that the ruminal fermentation pattern was not changed. • Reducing 30% Lys via rumen-protected lysine significantly decreased relative abundance of short-chain fatty acid-producing bacteria belonging to Firmicutes. • Functions of microorganisms were changed by reducing 30% Lys via rumen-protected Lys, especially amino acid metabolism. It may affect the amino acid composition of microprotein.

The Limiting Sequence and Appropriate Amino Acid Ratio of Lysine, Methionine, and Threonine for Seven- to Nine-Month-Old Holstein Heifers Fed Corn-Soybean M-Based Diet.

An "Amino acid (AA) partial deletion method" was used in this experiment to study the limiting sequences and appropriate ratio of lysine (Lys), methionine (Met), and threonine (Thr) in the diets of 7- to 9-month-old Holstein heifers. The experiment was conducted for three months with 72 Holstein heifers (age = 22 ± 0.5 weeks old; BW = 200 ± 9.0 kg; mean ± standard deviation). Following an initial two weeks adaptation period, heifers were allocated to one of four treatments: a theoretically balanced amino acid diet (positive control [PC]; 1.00% Lys, 0.33% Met, and 0.72% Thr), a 30% Lys deleted diet (partially deleted Lys [PD-Lys]; 0.66% Lys, 0.33% Met, and 0.72% Thr), a 30% Met deleted diet (partially deleted Met, [PD-Met]; 1.00% Lys, 0.22% Met, and 0.72% Thr), and a 30% Thr deleted diet (partially deleted Thr [PD-Thr]; 1.00% Lys, 0.33% Met, and 0.45% Thr). Experimental animals were fed a corn-soybean meal-based concentrate and alfalfa hay. In addition, the animals were provided with supplemental Lys, Met, and Thr (ruminal bypass). The results found no differences in the growth performance and nitrogen retention between PD-Thr treatment and PC treatment (p > 0.05). The average daily gain (p = 0.0013) and feed conversion efficiency (p = 0.0057) of eight- to ninr-month-old heifers were lower in both PD-Lys and PD-Met treatment than those in PC treatment. According to growth performance, Lys was the first limiting AA, followed by Met and Thr. Moreover, nine-month-old Holstein heifers in PD-Lys treatment and PD-Met treatment had higher levels of serum urea nitrogen (p = 0.0021), urea nitrogen (p = 0.0011) and total excreted N (p = 0.0324) than those in PC treatment, which showed that nitrogen retention significantly decreased (p = 0.0048) as dietary Lys and Met levels decreased. The limiting sequence based on nitrogen retention was the same as that based on growth performance. The appropriate ratio of Lys, Met, and Thr in the diet based on nitrogen retention was 100:32:57. In summary, the limiting sequence and appropriate amino acid ratio of Lys, Met, and Thr for seven- to nine-month-old Holstein heifers fed a corn-soybean meal-based diet were Lys > Met > Thr and 100:32:57, respectively.

Co-exposure to polycyclic aromatic hydrocarbons and metals, four common polymorphisms in microRNA genes, and their gene-environment interactions: Influences on oxidative damage levels in Chinese coke oven workers.

BACKGROUND: Human are often simultaneously exposed to polycyclic aromatic hydrocarbons (PAHs) and metals, yet relatively little is known regarding their co-exposure effects on oxidative damage. Genetic factors and the gene-environment interactions can also determine the severity of oxidative damage. Four polymorphisms in microRNA (miRNA) genes (rs11614913, rs2292832, rs2910164, and rs3746444) have been well-studied to be associated with oxidative damage-related diseases. OBJECTIVE: To investigate the influences of PAH-metal co-exposure, four polymorphisms, and their interactions on oxidative damage levels. METHODS: We conducted a cross-sectional study in 1385 coke oven workers. We quantified exposure levels of PAHs and metals by urinary monohydroxy-PAHs, plasma benzo[a]pyrene-7,8-diol-9,10-epoxide-albumin adducts, and urinary metals, respectively, and measured oxidative damage levels by 8-iso-prostaglandin-F2α and 8-hydroxydeoxyguanosine. We also genotyped four polymorphisms. RESULTS: In multiple-pollutant models, 8-iso-prostaglandin-F2α and 8-hydroxydeoxyguanosine were associated with multiple PAH exposure biomarkers, as well as with multiple metals (ptrend < 0.05). Metabolites of phenanthrene and pyrene interacted synergistically with lead and zinc to influence 8-iso-prostaglandin-F2α (ßinteraction > 7.75%, false discovery rate-adjusted pinteraction ≤ 2.25 × 10-5). Significantly higher 8-hydroxydeoxyguanosine was observed in carriers of rs11614913 CC variant homozygote than TC carriers (p = 0.037). Associations of the number of rs11614913 C allele with increased 8-iso-prostaglandin-F2α and 8-hydroxydeoxyguanosine were significant (ßstd > 0, ptrend < 0.05) and more pronounced in workers with lower metals [p for modifying effect (pME) < 0.040]. Positive associations of some PAHs and metals with 8-iso-prostaglandin-F2α and 8-hydroxydeoxyguanosine were weaker in carriers of rs11614913 CC genotype or C allele (pME < 0.05). CONCLUSION: PAH-metal co-exposure, rs11614913, and their interactions may affect oxidative damage levels in Chinese population in a complex manner that are worthy of further investigation.