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Abstract Covalent and non–covalent interactions between polyphenols and polysaccharides produced vital consequences on the sensory and nutritive qualities of the many foods. In the present study, the structure dependence of the non–covalent interactions between phenolic acids (PAs) and an arabinan–rich pectic polysaccharide from rapeseed meal (ARPP) was explored. Native RAPP and its hydrolysates as well as twenty–seven structurally diversified PAs were applied. The interaction was determined as the micrograms of PAs adsorbed by per milligram of polysaccharides (Q e , μg/mg). On one hand, the molecular weight (M w) of ARPP displayed a significant effect on the Q e of ferulic acid and a highest value (412.28 μg/mg) was obtained for the ARPP hydrolysate having a M w of 76 kDa. On the other hand, the substituent profile of PAs greatly affected their Q e values onto ARPP, although the results are monomer and substituent specific. Specifically, in terms of Q e , hydroxylation favored the interaction by 35.78% to 271.22%, while methylation and esterification weakened the absorption by 44.78% to 230.71% and 16.48% to 78.68%, respectively. The case of esterification is more complicated that the attachment of OCH 3 at 3 –position (−26.14% to −77.04%) is adverse but that at 5 –position is highly favorable (156.96% to 190.70%) for the interactions. [ABSTRACT FROM AUTHOR]

The sorption capacity of arabinan-rich pectic polysaccharide (ARPP) onto ferulic acid (FA) was investigated using equilibrium dialysis assays. UV and FT-IR spectra showed that FA was successfully adsorbed by ARPP. The effects of temperature, pH, buffer concentration, NaCl, and ethanol on sorption were investigated. Sorption variable optimization was examined by response surface methodology. The order of influence of each factor in affecting the sorption capacity was temperature > pH > buffer concentration. The maximum sorption yield was 363.92 ± 18.37 μg/mg at 36.8 °C, pH 5.26, and a buffer concentration of 0.09 M. Langmuir, Freundlich, and Temkin models were used to fit the experimental data under the optimized conditions. The Freundlich model showed the closest fit with an R 2 of 0.995 and a △ q % of 6.44. Scatchard plots of FA binding to ARPP indicated the existence of two types of binding sites, Type-1 and Type-2 , which followed the Freundlich model. Significant decreases in the sorption of FA at elevated NaCl and ethanol concentrations indicated that hydrogen bonding and electrostatic forces involved in the sorption of FA onto ARPP. [ABSTRACT FROM AUTHOR]

[Display omitted] • The degradation efficiency of napropamide is higher than that of metolachlor. • Enantioselective degradation more notable under aerobic conditions. • Plant fluorescence performance is an indicator of wetland biodegradation recovery. • Herbicide, plants, wetland hydraulics jointly influence microbial community structure. This study demonstrates the stereoselective degradation patterns and biodegradation mechanisms of metolachlor (MET) and napropamide (NAP) in integrated vertical flow constructed wetlands (IVCW). The higher interphase transferability of NAP resulted in higher degradation rates of 90.60 ± 4.09%. The enantiomeric fraction (EF) values of 0.38 ± 0.02 and 0.54 ± 0.03, respectively, recorded for the enantiomers S-MET and R-NAP, with higher herbicidal activities, demonstrated their highly selective biodegradation patterns. The antioxidant enzyme activities and fluorescence parameters of plants showed positive correlations with the degradation efficiency and enantioselectivity of MET and NAP. Adaptive regulations by plants promoted the proliferation of microbial genera like Enterobacter and unclassified_ Burkholderiales, which could facilitate plant growth. Moreover, enrichment of the herbicide-degrading functional bacteria Terrimonas (5.10%), Comamonas (4.05%) Pseudoxanthomonas (4.49%) and Mycobacterium (1.42%) demonstrably promoted the preferential degradation of S-MET and R-NAP. Furthermore, the abundance of Ferruginibacter favored the use of R-NAP as carbon source to achieve co-removal of R-NAP and NO 3 –-N. [ABSTRACT FROM AUTHOR]

This study demonstrates the enantioselective removal dynamics and mechanisms of the chiral herbicide metolachlor in a hydroponic system of Phragmites australis. It presents the first work to elucidate plant-microbial driven enantioselective degradation processes of chiral chemicals. The results showed a degradation efficiency of up to 95.07 ± 2.81% in the hydroponic system driven by a notably high degradation rate constant of 0.086 d−1. P. australis was demonstrated to rapidly increase the contribution of biodegradation pathways in the hydroponic system to 82.21 ± 4.81% within 4 d with an enantiomeric fraction (EF) drop to 0.26 ± 0.02 to favour the enantioselective degradation of S-Metolachlor (k S-Metolachlor = 0.568 d−1 and k R-Metolachlor = 0.147 d−1). Comparatively, the biodegradation pathways in the control constituted less than 25%, with an EF value of circa 0.5. However, the enantioselective biodegradation pathways exhibited complete reversal after about 4 d to favour R-Metolachlor. Plants promoted the degradation of R-Metolachlor, evidenced by an increase in EF to 0.59 ± 0.03. Nonetheless, metolachlor showed an inhibitory effect on plants reflected by the reduction of plant growth rate, chlorophyll content, and electron transport rate to −7.85 ± 1.52%, 1.33 ± 0.43 mg g−1, 4.03 ± 1.33 μmol (m2 s)−1, respectively. However, rhizosphere microorganisms aided plants to catalyze excessive reactive oxygen species production by the antioxidant enzymes to protect plants from oxidative damage and restore their physiological activities. High-throughput analysis of microbial communities demonstrated the enrichment of Massilia (40.63%) and Pseudomonas (8.16%) in the initial stage to promote the rapid degradation of S-Metolachlor. By contrast, the proliferation of Brevundimonas (32.29%) and Pseudarthrobacter (11.03%) in the terminal stage was closely associated with the degradation of R-Metolachlor. Moreover, as symbiotic bacteria of plants, these bacteria aided plants protection from reactive oxygen damages and promoted the recovery of plant metabolic functions and photosynthesis. Overall, these results demonstrate biodegradation mediated by plant-microbe mechanisms as the main driver for the enantioselective degradation of metolachlor in hydroponic systems. [Display omitted] • Metolachlor shows stereoselective degradation characteristics in hydroponics. • The stereoselective degradation of Metolachlor is reversible. • Plants aid enrichment of Metolachlor-degrading microbes and removal of enantiomers. • Rhizosphere microbes promote reactive oxygen damage recovery and growth of plants. [ABSTRACT FROM AUTHOR]

Feruloyl amylopectin (FAP) was synthesized by the N , N ′-carbonyldiimidazole (CDI) activation method, and the enzymatically cross-linked feruloyl amylopectin (CL-FAP) was prepared via catalysis of horseradish peroxidase (HRP) with the presence of hydrogen peroxide (H 2 O 2 ). RP-HPLC-DAD/ESI-TOF-MS measured ferulic acid and its derivatives in FAP and CL-FAP. FAP was primarily composed of two ferulate monomers, while CL-FAP was composed of two ferulate monomers and two ferulate dehydrodimers. The ester formation in the feruloyl group was confirmed by the presence of carbonyl and aromatic C C signal near 1725 (1723) and 1510 cm −1 in the FT-IR spectra. X-ray diffraction studies showed that the two modified amylopectins lost the ordered A-type crystalline structure, characteristic of maize amylopectin. The encapsulation capacity of curcumin ( ECC ) in 1 mg/mL CL-FAP microemulsion was measured at 88.13 μg/mg by HPLC. [ABSTRACT FROM AUTHOR]

• Summary of the mechanical properties of CoNi-based medium entropy alloys (MEAs) grouped into the CoNiFe, CoNiCr, and CoNiV MEAs are provided. • The influence of short-range ordering characteristics on these CoNi-based MEAs and the potential practical applications from the high-entropy superalloy design perspective are also discussed. The concept of alloying has evolved over the centuries and in the past decade and a half, the emergence of the high entropy alloying concept has completely changed our perception of alloy design. This alloying strategy has been found to exhibit exciting properties such as high strength, excellent corrosion resistance, high cryogenic fracture toughness, thermal stability, and irradiation resistance. While the fcc-structured equiatomic CrMnFeCoNi has been very popular over the years, the discovery of the superior properties by a ternary CoNiCr alloy, kick-started a new era for medium-entropy alloy-focused research in the last 5–10 years due to the realization that "medium is better". Here we review the recent progress made in the development of medium entropy alloys from a binary CoNi building block (CoNi-M, where M is Fe, Cr, or V), which are prototype systems of medium-entropy alloys. We discuss the relationship between their microstructure and properties (mainly mechanical ones), and how the stacking fault energy, and/or short-range order (SRO) determines the corresponding deformation mechanism. The influence of minor-alloying on their crystal structure and variations in deformation modes are critically discussed. Lastly, some insights and challenges are outlined. [ABSTRACT FROM AUTHOR]

Deformation-induced martensitic transformation in Fe-Co-Ni-Cr-Mn high entropy alloy (HEA) thin film with nanocolumnar growth feature are revealed to readily occur at intermediate deposition power rather than low and high deposition power ranges. The high probability of deformation-induced martensitic transformation from face-centered cubic (FCC) to hexagonal close-packed (HCP) phase in 150 W-film results in low nanoindentation hardness and compressive yield strength, in comparison with 60 W- and 210 W-films. Dependence of the martensitic transformation probability has been explained in terms of the competition between grain size effect and nanocolumn cohesion effect on the phase metastability. The increased grain size with deposition power favors the mechanical instability of FCC parent phase caused by the weakened slip obstruction, while the enhanced nanocolumn cohesion with deposition power hinders the formation of HCP martensite due to the increased activation energy for martensitic transformation. The grain size effect is dominated over the cohesion between nanocolumn at low deposition power range, while column cohesion effect is dominant at high deposition power range, which gives rise to the crossover of FCC-to-HCP with deposition power. This work might provide a deeper understanding in phase metastability of sputtered films, for instance, the effect of deposition power on deformation-induced martensitic transformation. • The deformation-induced martensitic transformation is observerd in Fe-Co-Ni-Cr-Mn high entropy alloy (HEA) thin film. • The crossover of FCC-to-HCP with deposition power is discovered, in which the high probability exists in 150 W-film.; • The elucidation of the underlying mechanisms for this unusual deformation-induced martensitic transformation behavior. [ABSTRACT FROM AUTHOR]

Insufficient carbon source/electron donor often limits the denitrification efficiency of constructed wetlands (CWs) when treating wastewater characterized by low carbon-to-nitrogen ratios. Hence, the viability of wetland plant-based carbon sources for enhanced nitrogen removal and its mechanisms in horizontal subsurface flow CWs was assessed. Results showed cattails to have a better carbon release capacity than wheat straw and corn cob. Alkali pretreatment of cattails is demonstrated to significantly enhance the release of volatile fatty acids (68.31 ± 1.36 mg/g) dominated by acetic acid to sustain a high denitrification rate (0.62 ± 0.05 mg/(L·h)) over a long duration. External carbon source addition to adjusting C/N ratio to 3.5 achieved the highest removal rates of 75.45%, 91.33% and 76.03%, respectively, for total nitrogen (TN), ammonia-nitrogen (NH 4 +-N) and nitrate-nitrogen (NO 3 −-N). High-throughput sequencing showed plant-based external carbon sources to significantly increase the relative abundance of the denitrifying bacteria , as well as the anammox bacteria. Moreover, it elevated the number of nitrate reductase relative to nitrite reductase by 4.65-fold. Plant-based external carbon sources enhanced the partial denitrification-anammox (PDN/AMX) contribution to TN removal by at least 27.29% and improved nitrogen removal efficiency through co-promotion of denitrification and PDN/AMX pathways. Findings from this study support the utilization of plant-based external carbon sources in CWs. Additionally, it provides new insights into enhancement pathways of nitrogen removal with plant-based carbon sources. [Display omitted] • Cattails are more suitable than crops for use as a plant-based carbon source. • Alkali pretreatment enhanced the release and bioavailability of volatile fatty acids. • Plant-based C enhance N removal via denitrification, PDN/AMX pathways. • C/N ratios of 2.5 and 3.5 favored the occurrence of PDN/AMX pathways. [ABSTRACT FROM AUTHOR]

The corrosion behaviors of (CoNiV) 100−x Al x (x = 0, 3, 5 at.%) MEAs in NaCl and H 2 SO 4 solutions have been systematically investigated. The corrosion properties of CoNiV alloys with different average grain sizes in the Cl−1 ions containing solution seems to be related to the proportion of (100) orientation plane. The Al addition results in the enhanced corrosion resistance in NaCl solution and no obvious difference in H 2 SO 4 solution. Oxides of V are the main components of the passive films formed on CoNiV and (CoNiV) 97 Al 3 alloys. The enrichment of the V- and Al- oxides in the passive film on the (CoNiV) 95 Al 5 alloy improves corrosion resistance. • Al addition enhances corrosion resistance of CoNiV MEA in 3.5 wt.% NaCl solution. • The corrosion of CoNiV MEA is related to the proportion of (100) orientation plane. • The concentration of ions in the solution states selective dissolution did not occur. • The passive ability of CoNiV MEA is similar to the nature of V element. • The V and Al oxides enriched layer on (CoNiV) 95 Al 5 MEA improves corrosion resistance. [ABSTRACT FROM AUTHOR]

Via tuning deposition power, a series of Co-Ni-V medium entropy alloy thin films, growing in a nanocolumn manner, with different microstructures and morphologies were synthesized. With increasing fluence, both the crystallinity and nanocolumn size experienced a process of first increasing and then decreasing, controlled by the adatom surface diffusion vs. deposition rate competition. Meanwhile, continuous strengthening with fluence was ascribed to improved bonding and reduced fraction of boundary at low fluence and amorphization reinforcement effect in high fluence range. [Display omitted] [ABSTRACT FROM AUTHOR]

Pressure-dependent atomic packing structure changes of newly designed sulfur-bearing metallic glass (MG) of Pd 37 Ni 37 S 26 have been studied by in situ high energy X-ray diffraction and resistivity experiments, and ab initio molecular dynamics simulations from ambient pressure up to 40.9 GPa. Local structural transformation from a low-density amorphous state into high-density one at about 12.8~15.4 GPa has been revealed, which originates from the noticeable kinks during the electron back-donations from S atoms to more localized Ni 3 d orbital at about 13~15 GPa and is confirmed by the pressure-dependent resistivity measurements. The origin for the transition is uncovered, i.e., Pd- and Ni-centered clusters first transfer from icosahedral-like structures into higher-coordinated ones, which dominates the initial densification of Pd 37 Ni 37 S 26 MG during the compression below 13 GPa. In the pressure range above 15 GPa, the low-coordinated S -centered clusters transform into the tri-capped trigonal prism-like structures during the compression of Pd 37 Ni 37 S 26 MG up to 40.9 GPa. All results obtained here provide insight into the local structural evolution of the sulfur-bearing MGs with pressure. [Display omitted] [ABSTRACT FROM AUTHOR]

• METH elevates the protein expression levels of LC3B and Beclin-1 in a dose- and time-dependent manner. • Gastrodin blocks the METH-induced upregulation of LC3B and Beclin-1 protein expression. • Gastrodin exhibits an anti-autophagic effect to inhibit the METH-induced Beclin-1 protein expression, partly via the AKT/mTOR pathway. Methamphetamine (METH) has been shown to induce neuropathological dysfunction and irreversible brain cell damage. Prior studies indicated the involvement of autophagy in METH-induced neurotoxicity. However, the underlying mechanism by which autophagy contributes to METH-induced neurotoxicity remains elusive. Gastrodin, a primary bioactive constituent of Gastrodia elata— an orchid used in traditional Chinese medicine—is used widely to treat stroke, dementia, and headache. This study investigates whether METH induces autophagy in the human dopaminergic neuroblastoma cell line SH-SY5Y, then examines the neuroprotective effects of gastrodin against autophagy in METH-treated SH-SY5Y cells. The effects of METH on the protein expressions of autophagy-related genes (LC3B and Beclin-1) were evaluated with and without gastrodin. The presence of autophagosomes in the METH-induced treatment with and without gastrodin is revealed through transmission electron microscopy. Pharmacological intervention was employed to study the role of the AKT/mTOR signaling pathway in the gastrodin-mediated neuroprotection against METH-induced autophagy. The present results indicate that METH exposure elevates the protein expression levels of LC3B and Beclin-1 in a dose- and time-dependent manner. Gastrodin is observed to block the METH-induced upregulation of LC3B and Beclin-1 protein expression significantly. Gastrodin is found to exhibit an anti-autophagic effect on the inhibition of the METH-induced Beclin-1 protein expression, partly via the AKT/mTOR These findings may aid the development of a gastrodin-based therapeutic strategy for treating METH-induced neurotoxicity. [ABSTRACT FROM AUTHOR]