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Hydration‐induced shape‐morphing behavior has been discovered in many natural fiber‐based materials, yet this smart behavior in regenerated fibers from biopolymers lacks investigation. Here, hierarchically structured silk fibers are developed with anisotropic long‐range molecular organization and water‐responsive effects resembling natural spider silk. The regenerated silk fibers exhibit the water‐triggered shape‐memory effect and a water‐driven cyclic response. The reversible hydrogen bonds and transformation in the metastable secondary structure from α‐helices/random coils to β‐sheets are explored as the mechanisms responsible for the water‐responsiveness. The silk fibers obtained possess a tensile strength higher than 104 MPa at a fracture strain of ≈100%, showing noticeable toughness. The water‐responsive silk fibers exhibit a shape recovery rate of ∼83% and generate a maximum actuation stress of up to 18 MPa during the water‐driven cyclic contraction that outperforms most traditional natural textile fibers. The regenerated silk fibers show potential for use in water‐driven actuators, artificial muscle, and smart fabrics based on the integration of suitable mechanical properties and water responsiveness. [ABSTRACT FROM AUTHOR]

BACKGROUND RESULTS CONCLUSION Future applications of high‐internal‐phase emulsions (HIPEs) are highly regarded, but poor freeze–thaw stability limits their utilization in frozen products. This study aimed to characterize the structure of chickpea protein microgel particles (HCPI) induced by NaCl and to assess its impact on the freeze–thaw stability of HIPEs.The results showed that NaCl induction (0–400 mmol L−1) increased the surface hydrophobicity (175.9–278.9) and interfacial adsorbed protein content (84.9%–91.3%) of HCPI. HIPEs prepared with HCPI induced by high concentration of NaCl exhibited superior flocculation index and centrifugal stability, and their freeze–thaw stability was better than that of natural chickpea protein. The increase in NaCl concentration reduced the droplet aggregation and coalescence index of the freeze–thaw emulsions, diminishing the precipitation of oil from the emulsion. Linear and nonlinear rheology showed that the strengthened gel structure (higher G′ values) restricted water flow and counteracted the damage to the interfacial film by ice crystals at 100–400 mmol L−1 NaCl, thus improving the viscoelasticity of the freeze–thaw emulsions. Finally, the thawing loss of surimi gel with HCPI‐200 HIPE was reduced by 2.04% compared to directly adding oil.This study provided a promising strategy to improve the freeze–thaw stability of HIPEs and reduce the thawing loss of frozen products. © 2024 Society of Chemical Industry. [ABSTRACT FROM AUTHOR]

A total of 43 compounds, including phenolic acids, flavonoids, lignans, and diterpene, were identified and characterized using UPLC‐ESI‐Q‐TOF‐MS coupled with UNIFI software. The identified flavonoids were mostly isomers of luteolin, apigenin, and quercetin, which were elucidated and distinguished for the first time in pepper cultivars. The use of multivariate data analytics for sample discrimination revealed that luteolin derivatives played the most important role in differentiating pepper cultivars. The content of phenolic acids and flavonoids in immature green peppers was generally higher than that of mature red peppers. The pepper extracts possessed significant antioxidant activities, and the antioxidant activities correlated well with phenolic contents and their molecular structure. In conclusion, the findings expand our understanding of the phytochemical components of the Chinese pepper genotype at two maturity stages. Moreover, a UPLC‐ESI‐Q‐TOF‐MS in negative ionization mode rapid methods for characterization and isomers differentiation was described. [ABSTRACT FROM AUTHOR]

Conductive hydrogels possessing high conductivity, stretchability, and biocompatibility are promising materials for underwater devices and bioelectronics. However, typical hydrogels often exhibit low electrical conductivity, which is insufficient for applications requiring high electronic communication. A common approach to increase hydrogel conductivity is to introduce conductive fillers; however, this usually implies a partial sacrifice of stretchability, biocompatibility, and water content. In addition, the electrical properties of hydrogels tend to be unstable due to rehydration in aqueous environments. In this study, a conductive hydrogel composite is fabricated from silver nanowires (AgNWs) and poly(vinyl alcohol) (PVA) employing a synergistic method of freezing and salting‐out treatments. This combined method constructs a hierarchical hydrogel structure and increases the local concentration of AgNWs by inducing continuous phase separation. The resultant conductive hydrogel composites exhibit ultra‐high electrical conductivity (≈1739 S cm−1) and electrical stability in aqueous environments while maintaining high water content (≈87%), stretchability (≈480%), and excellent biocompatibility. To illustrate the capabilities of the conductive hydrogel composites, they are applied to bionic sharks, underwater soft circuitry, and electrocardiogram electrodes. [ABSTRACT FROM AUTHOR]

A key challenge to apply aqueous zinc metal batteries (AZMBs) as next‐generation energy storage device is to improve the rechargeability at high current densities, which is needed to circumvent slowly ion diffusion in anode and sluggish charge transfer of Zn2+. Herein, a zincophilic accordion array derived from MOF is developed as zinc host for simultaneously boosted ion diffusion and charge transfer. The designed host is prepared by etching and disproportionation reactions, the abundant zincophilic Sn sites with nano‐size uniform disperse on accordion arrays nanosheets (Sn‐AA). Then a composite Zn anode (Sn‐AA@Zn) is obtained by compacting Sn‐AA host with zinc power (Zn‐P). The Sn‐AA@Zn anode has an ultra‐low activation energy (37.1 kJ mol−1) and nucleation overpotential (10 mV), achieving fast charge transfer of Zinc deposition. In addition, the cycle life of the symmetric cell with Sn‐AA@Zn anode exceeds 13 000 cycles at 50 mA cm−2, which is 32 times than that of the Zn‐P anode. And the full cell with Sn‐AA@Zn anode and MnO2 cathode maintains a capacity of 122 mAh g−1 after 5000 cycles at 5 Ag−1. Hopefully, the 3D anode based on Sn‐AA@Zn accordion array and Zn‐P has significantly improved the rechargeability of AZMB at high current density. [ABSTRACT FROM AUTHOR]

A key challenge to apply aqueous zinc‐metal batteries (AZMBs) as next‐generation energy storage devices is to eliminate the adverse reactions of hydrogen evolution, especially in low current. Here, superhydrophobic and ionophilic artificial solid electrolyte interface (HI‐SEI) on zinc anode is proposed and constructed by enhancing roughness and etching ion channels in universal polysiloxane polymer backbones. The HI‐SEI exhibits superhydrophobicity with high contact angle of 151.5° and ionophilicity with low activation energy of 23.97 kJ mol−1. Thus, the HI‐SEI isolates Zn metal and solvent water and promotes desolvation kinetics of Zn2+. Besides, the HI‐SEI alters the double electric layer structure to form a compact layer hardly any adsorbed solvent water, achieving a small nucleation overpotential of 5 mV and low self‐corrosion current density of 0.95 µA cm−2. Moreover, a symmetric cell with HI‐SEI@Zn anode has a cycle life of >1330 h at low current of 0.1 mA cm−2. And a full cell with HI‐SEI@Zn anode and NaV3O8‐1.5H2O cathode provides long cycle life and low capacity degradation (180 mAh g−1 after 1100 cycles). Hopefully, SEI designs based on such a strategy will be able to improve the low‐current cycling performance of the next‐generation AZMBs. [ABSTRACT FROM AUTHOR]

The involvement of hydrogen energy systems has been recognised as a promising way to mitigate climate problems. As a kind of efficient multi‐energy complementary system, the hydropower‐photovoltaic‐hydrogen (HPH) system could be an ideal approach to combining hydrogen with an installed renewable energy system to improve the flexibility of energy management and reduce power curtailment. However, the intra‐day scheduling of HPH system brings challenges due to the time‐related nonlinear hydropower generation process, the complex energy conversion process and the uncertain natural resource supply. Faced with these challenges, an improved deep deterministic policy gradient (DDPG)‐based data‐driven scheduling algorithm is proposed. In contrast to the prevalent DDPG, two sets of actor‐critic networks are properly designed based on prior knowledge‐based deep neural networks for the considered complex uncertain system to search for near‐optimal policies and approximate actor‐value functions. In addition, customized reward functions are proposed with the consideration of interactions among different energy supplies, which helps to improve convergence speed and stability. Finally, the case study results demonstrate that the proposed system model and the optimal energy management strategy based on the improved DDPG algorithm can guide the electricity‐hydrogen system to achieve rapid response and more reasonable energy management. [ABSTRACT FROM AUTHOR]

Current intramuscular vaccines cannot effectively prevent severe acute respiratory syndrome coronavirus 2 (SARS‐CoV‐2) transmission and infection in nasal epithelium. Although face masks represent an additional preventive measure against SARS‐CoV‐2, their low breathability hinders wearing compliance. Herein, the development of SuperNeut, a protein‐based breathable high‐efficiency face mask, is reported. The mask contains KP‐LCB1, a fusion protein that can capture SARS‐CoV‐2 spike proteins on one end and attach to keratin fibres on the other. The meltblown fabric is replaced by a thin electrospun keratin layer that allows uniform adhesion of KP‐LCB1, which serves as an effective barrier to filter incoming viruses, while substantially improving breathability. The studies demonstrate that the fusion protein is stable and can efficiently neutralise multiple SARS‐CoV‐2 wildtype (WT), Alpha (B.1.1.7), Delta (B.1.617.2), and Omicron (B.1.1.529). The breathability of SuperNeut mask compared to commercial surgical masks is also quantified. Importantly, it is shown that SuperNeut Mask is able to effectively prevent SARS‐CoV‐2 Delta transmission in Syrian hamster model. Overall, the highly breathable SuperNeut mask can efficiently prevent SARS‐CoV‐2 transmission. This design serves as a proof‐of‐concept that face mask designs can be improved with biological components. The neutralising proteins in this mask can be altered to combat future respiratory disease outbreaks. [ABSTRACT FROM AUTHOR]

Lateral ankle sprains (LAS) might lead to joint sensory deafferentation, which induces maladaptive neuroplasticity, especially the morphological atrophy of the cerebellar vermis. However, longitudinal evidence on the causality of injury and neural differences is still lacking. To this end, this study aimed to determine whether the morphology of the central nervous system would be altered before and after ligament transection in LAS mouse models. A total of 40 C57BL/6 mice were randomly divided among the LAS, Sham and Blank groups. We repeatedly performed the balance beam test and neural voxel‐based morphometry (VBM) measurements using an 11.7 T magnetic resonance imaging before and 2 months after the surgery. The results showed that for balance outcomes, the LAS group had a significantly longer time and more slips of the balance beam tests compared with the Sham and Blank groups at 2 months after surgery, with no significant difference among the three groups before surgery. Regarding the VBM analysis, the LAS group showed significantly lower VBM values in the central lobule III of the cerebellar vermis and medial amygdalar nucleus (MEA) compared with the Sham and Blank groups after surgery, with no significant difference among the three groups before surgery. In conclusion, lateral ligament injuries might lead to morphological atrophy of the cerebellar vermis in animal models, which might pave the way for the pathological process of ankle instability after LAS. [ABSTRACT FROM AUTHOR]

Summary: Rich in flavonoids, orange peel (OP) converted into tangerine peel (TP) after long‐term storage and metabolism by surface microorganisms. The antioxidant activity of OP increased during ageing, but underlying mechanisms were still not clear. The current study simulated the ageing process by inoculating Aspergillus niger on OP. Antioxidant activity, total flavonoids, enzyme activities and hesperidin content were analysed at different fermentation times. The results showed that antioxidant activity was constantly increased and relatively consistent with total flavonoids. The maximum growth rate of antioxidant activity and total flavonoids appeared in 24–48 h. Total flavonoids content increased from 4.68 ± 0.04 to 8.32 ± 0.15 mg RE/g and positively co‐relate with cellulase and β‐glucosidase activities. During fermentation, nine flavonoids content accumulated, except that hesperidin began to convert into hesperetin after 72 h. In summary, these findings suggested that A. niger fermentation, which led to an increase in antioxidant activity, promoted the accumulation of flavonoids and transformation of hesperidin in OP. This study provided a microbial method for the effective utilisation of OP pomace. [ABSTRACT FROM AUTHOR]

Peatlands are important reservoirs of terrestrial carbon (C), whose fate can have implications for the global C cycle and climate change. Many peatlands around the world have been drained for agriculture and forestry and restored later on hoping to reduce C emissions and improve water quality. However, the actual effects of these management practices remain unclear. To address this, we investigated the concentration and quality of dissolved organic C (DOC) and water chemistry (nutrient and Fe concentrations) in the surface water (creeks and ditches) of the natural, drained, and restored areas along an elevation gradient of the Baijianghe (BJH) peatland in northeast China from 2017 to 2020. We found significantly higher DOC concentrations in the natural than the drained area, with a heavier, more fulvic, and less aromatic DOC composition upslope, but the difference in DOC quality became smaller downslope. Restoration, on the other hand, did not bring DOC concentrations or quality back to the natural conditions within 2 years. These variations in DOC concentration and quality were closely associated with dissolved Fe concentration, highlighting the role of the Fe redox cycle, as Fe(II) can catalyse phenol oxidation activities and promote DOC production. Vegetation also affected DOC characteristics, as the drained and restored areas were dominated by shrubs with woodier tissues, which probably released less in amount but more recalcitrant DOC. Our study features rare side‐by‐side comparisons between pristine, drained, and restored areas of the same peatland, and sheds light on factors affecting peatland DOC under different management practices. [ABSTRACT FROM AUTHOR]

Central π‐core engineering of non‐fullerene small molecule acceptors (NF‐SMAs) is effective in boosting the performance of organic solar cells (OSCs). Especially, selenium (Se) functionalization of NF‐SMAs is considered a promising strategy but the structure‐performance relationship remains unclear. Here, we synthesize two isomeric alkylphenyl‐substituted selenopheno[3,2‐b]thiophene‐based NF‐SMAs named mPh4F‐TS and mPh4F‐ST with different substitution positions, and contrast them with the thieno[3,2‐b]thiophene‐based analogue, mPh4F‐TT. When placing Se atoms at the outer positions of the π‐core, mPh4F‐TS shows the most red‐shifted absorption and compact molecular stacking. The PM6 : mPh4F‐TS devices exhibit excellent absorption, high charge carrier mobility, and reduced energy loss. Consequently, PM6 : mPh4F‐TS achieves more balanced photovoltaic parameters and yields an efficiency of 18.05 %, which highlights that precisely manipulating selenium functionalization is a practicable way toward high‐efficiency OSCs. [ABSTRACT FROM AUTHOR]

Halogenation of terminal of acceptors has been shown to give dramatic improvements in power conversion efficiencies (PCEs) of organic solar cells (OSCs). Similar significant results could be expected from the halogenation of the central units of state‐of‐the‐art Y‐series acceptors. Herein, a pair of acceptors, termed CH6 and CH4, featuring a conjugation‐extended phenazine central unit with and without fluorination, have been synthesized. The fluorinated CH6 has enhanced molecular interactions and crystallinity, superior fibrillar network morphology and improved charge generation and transport in blend films, thus affording a higher PCE of 18.33 % for CH6‐based binary OSCs compared to 16.49 % for the non‐fluorinated CH4. The new central site offers further opportunities for structural optimization of Y‐series molecules to afford better‐performed OSCs and reveals the effectiveness of fluorination on central units. [ABSTRACT FROM AUTHOR]

BACKGROUND Artemisia selengensis Turcz. (AST) is a common edible and medicinal herb possessing extensive biological activities and various health‐promoting functions. However, the anti‐aging effects of AST have been neglected. This work evaluated the effects of AST leaf extract (ASTE) on stress tolerance and longevity in Caenorhabditis elegans. RESULTS: ASTE treatment enhanced stress resistance and significantly extended the lifespan of C. elegans. Moreover, ASTE prolonged the healthspan by increasing body bending and pharyngeal pumping rates, and by reducing the intestinal lipofuscin level and accumulation of intracellular reactive oxygen species (ROS). Caffeoylquinic acids in ASTE, especially dicaffeoylquinic acids, were the major components responsible for these benefits. The mechanism underlying the anti‐aging effect of ASTE occurred by activating insulin/insulin‐like growth factor, SIR‐2.1 signaling and mitochondrial dysfunction pathways, which in turn induced the activity of the transcription factors DAF‐16/FOXO and SKN‐1/Nrf2. CONCLUSION: These findings provide direct evidence for the anti‐aging effects of AST and reveal its potential on promoting healthy aging. © 2022 Society of Chemical Industry. [ABSTRACT FROM AUTHOR]

Core–shell nanocomposites have attracted extensive attention in the photoelectric field because of their improved material properties and the combination of multiple functions. Particularly, these nanocomposites exhibit tunable structure and excellent optical properties. Inspired by these unique features, a novel optically active nanocomposites, Y2O3:Eu3+@SiO2 with a core–shell structure, is designed and fabricated by a hydrothermal method and electrophoretic deposition. In addition, the Y2O3:Eu3+@SiO2 composite film is also successfully developed and applied as a spectral down‐converter in the solar‐blind ultraviolet (UV) waveband region of 200–280 nm. Moreover, a broadband solar‐blind UV photodetector device is elaborated and a notable enhancement in the UV sensitivity is achieved. The findings not only provide a new idea for the development of broadband solar‐blind UV photodetector but also extended the application range of core–shell nanocomposites in photonics. [ABSTRACT FROM AUTHOR]

Side‐chain modifications of non‐fullerene acceptors (NFAs) are essential for harvesting their full potential in organic solar cells (OSC). Here, an effective alkyl‐chain‐branching approach of the Y‐series NFAs flanking meta‐substituted phenyl side groups at the outer positions is demonstrated. Compared to BTP‐4F‐PC6 with linear m‐hexylphenyl chains, two new acceptors named BTP‐4F‐P2EH and BTP‐4F‐P3EH are developed with bulkier alkyl chains branched at the β and γ positions, respectively. These branched chains result in altered molecular packing of the NFAs and afford higher open‐circuit voltage of the devices. Despite the blue‐shifted absorption of the branched‐chain NFAs, their blends with PBDB‐T‐2F enable improved short‐circuit current density for the corresponding devices owing to the more suitable phase separation and better exciton dissociation. Consequently, the OSCs based on BTP‐4F‐P2EH and BTP‐4F‐P3EH yield enhanced device performance of 18.22% and 17.57%, respectively, outperforming the BTP‐4F‐PC6‐based ones (17.22%). These results highlight that the side‐chain branching design of NFAs has great potential in optimizing molecular properties and promoting photovoltaic performance. [ABSTRACT FROM AUTHOR]

Background and Purpose: Identification of changesin brain microstructure following mild traumatic brain injury (mTBI) could be instrumental in understanding the underlying pathophysiology. The purpose of this study was to apply neurite orientation dispersion and density imaging (NODDI) to a rodent model of mTBI to determine whether microstructural changes could be detected immediately following injury.Methods: Fifteen adult male Wistar rats were scanned on a Bruker 9.4 Tesla small animal MRI using a multi-shell acquisition (30 b = 1000 s/mm2 and 60 b = 2000 s/mm2 ). Nine animals experienced a single closed head controlled cortical impact followed by NODDI from 1 to 4 h post injury. Region of interest analysis focused on the corpus callosum and hippocampus. A mixed analysis of variance (ANOVA) was used to determine statistically significant interactions in neurite density index (NDI), orientation dispersion index (ODI), fractional anisotropy (FA), mean diffusivity (MD), axial diffusivity (AD), and radial diffusivity. Follow up repeated-measures ANOVAs were used to determine individual changes over time.Results: NDI showed a significant increase in the hippocampus and corpus callosum following injury, while ODI showed increases in the corpus callosum. No significant changes were observed in the sham control animals. No changes were found in FA, MD, AD, or RD. Histological analysis revealed increased glial fibrillary acidic protein staining relative to controls in both the hippocampus and corpus callosum, with evidence of activated astrocytes in these regions.Conclusions: Changes in NODDI metrics were detected as early as 1 h following mTBI. No changes were detected with conventional diffusion tensor imaging (DTI) metrics, suggesting that NODDI provides greater sensitivity to microstructural changes than conventional DTI. [ABSTRACT FROM AUTHOR]

Poly(vinyl alcohol) (PVA) sizes are widely used in textile industry due to their excellent sizing properties on synthetic fibers and their blends. However, PVA contains non‐biodegradable chemicals and is a major contributor to environmental pollution related to the textile industry. To overcome this problem, an environmental‐benign and highly thermal‐resistant yarn coating is fabricated from soy proteins, an agricultural byproduct. The soy proteins are chemically modified by glycols having varying chain lengths and number of hydroxyl groups. Compared with the physically modified soy proteins and their sized yarns, coating made from the soy proteins esterified by 1,4‐butanediol show 91.38% increment in work of rupture at 120 °C and cotton/polyester (65/35) yarns sized by 1,4‐butanediol esterified soy protein sizes have 39.91% decrease in coefficient of friction. In addition, 1,4‐butanediol esterified soy sizes have a five‐day biochemical oxygen demand/chemical oxygen demand of 0.476, indicating that the chemically modified soy sizes have high biodegradability in activated sludge. Successful utilization of modified soy sizes can promote large‐quantity applications of soy byproducts, impelling high value addition to agricultural byproducts and sustainability of textile industry. [ABSTRACT FROM AUTHOR]

Summary: Gel‐like emulsions were produced by high‐intensity ultrasound (HIU) emulsification using soy protein as an emulsifier. Sunflower (a seed kernel oil), peanut (a groundnut oil), hazelnut, walnut, almond and pine nut oils were chosen as oil phases. The kinds of nut oil significantly affect the structures and properties of gel‐like emulsions. The particle size of sunflower oil gel‐like emulsion was smallest. Moreover, the macrorheological and microrheological results indicated that the values of apparent viscosity, storage modulus (G′) and elasticity index (EI) of sunflower and almond oil gel‐like emulsions were higher while those of the walnut and pine nut oil gel‐like emulsions were lower. Moreover, the sunflower oil gel‐like emulsion was more stable after 2‐month storage. The current study illustrated that HIU was of great importance for the production of high‐viscosity gel‐like emulsions. Furthermore, the differences of nut oils resulted in diverse physicochemical properties of gel‐like emulsions. [ABSTRACT FROM AUTHOR]

BACKGROUND: As an essential trace element for mammalian species, selenium (Se) possesses powerful antioxidant properties and is a potential regulator of intestinal microbiota. However, effects of Cardamine hupingshanensis aqueous extract (CE), rich in Se, on balancing the intestinal redox status and regulating gut microbiota have been neglected. RESULTS: An Se‐deficient rat model was established by feeding a low‐Se diet (LD) for 5 weeks and CE was then supplemented to LD or normal‐Se‐diet (ND) rats. Antioxidant enzyme activities and short‐chain fatty acids (SCFA) concentration were increased by CE in both LD and ND rats. CE improved the intestinal morphology of LD rats impaired by deficient Se. Intestinal microbiota demonstrated various changes; for example, Butyrivibrio was increased in LD rats, while Bacteroides, Christensenellaceae, Clostridiaceae and Blautia were enhanced in ND rats. CONCLUSION: Our findings provide evidence that CE shows potential in improving intestinal redox status and regulating gut microbiota. © 2020 Society of Chemical Industry [ABSTRACT FROM AUTHOR]

Organic contaminants in agricultural soils are widely reported; however, their accumulation patterns are quite different among regions. This study reports the distribution, accumulation and risk assessment of polycyclic aromatic hydrocarbons (PAHs), dichlorodiphenyltrichloroethane (DDT) and hexachlorocyclohexane (HCH) in soils from the Corn Belt of northeast China at a regional scale. Concentrations of PAHs, DDT and HCH were 306‐5300, 6.00–82.0 and 4.07–15.6 ng g−1, respectively. Source analysis suggests PAHs were derived from regional combustion of biomass and coal, except where sites are strongly affected by local sources. The DDT and HCH residues in soils are likely to be derived from previous agricultural applications that have persisted due to slow microbiological degradation under low mean temperatures. Precipitation was only significantly correlated with PAH concentrations, suggesting that precipitation affected PAH but not DDT and HCH distributions at a regional scale. Positive correlations between DDT concentrations and total organic carbon (TOC) contents of soils suggest hydrophobic organic contaminants were associated with organic matter. In contrast, TOC contents were correlated with PAHs in alfisols but not in pedocals. Pedocals contained mainly high molecular weight PAHs, indicating that eluviation affected the accumulation of less hydrophobic organic contaminants. Different correlations between low‐molecular‐weight PAH and HCH concentrations with TOC contents were found in alfisols, suggesting that contaminant structure may also affect the accumulation of less hydrophobic organic contaminants in these soils. Risk analysis suggested that potential ecological risks related to soils in the Corn Belt may lead to reduced maize production and the potential for human health risks in the future. Highlights: Few studies focus on regional‐scale factors that affect organic contaminant accumulation in soils.Environmental process affects less hydrophobic organic contaminant distribution at regional scale.Precipitation and eluviation affected accumulation of less hydrophobic contaminants in soils.PAH and OCP residues in the soil of maize fields may pose ecological risks affecting future crop production and human health. [ABSTRACT FROM AUTHOR]

BACKGROUND: Polyphenol oxidase (PPO) is considered a problem in the food industry because it starts browning reactions during fruit and vegetable processing. Ultrasonic treatment is a technology used to inactivate the enzyme; however, the mechanism behind PPO inactivation is still unclear. For this reason, the inactivation, aggregation, and structural changes in PPO from quince juice subjected to ultrasonic treatments were investigated. Different intensities and times of ultrasonic treatment were used. Changes in the activity, aggregation, conformation, and structure of PPO were investigated through different structural analyses. RESULTS: Compared to untreated juice, the PPO activity in treated juice was reduced to 35% at a high ultrasonic intensity of 400 W for 20 min. The structure of PPO determined from particle size distribution (PSD) analysis showed that ultrasound treatment caused initial dissociation and subsequent aggregation leading to structural modification. The spectra of circular dichroism (CD) analysis of ultrasonic treated PPO protein showed a significant loss of α‐helix, and reorganization of secondary structure. Fluorescence analysis showed a significant increase in fluorescence intensity of PPO after ultrasound treatment with evident blue shift, revealing disruption in the tertiary structure. CONCLUSION: In summary, ultrasonic treatment triggered protein aggregation, distortion of tertiary structure, and loss of α‐helix conformation of secondary structure causing inactivation of the PPO enzyme. Hence, ultrasound processing at high intensity and duration could cause the inactivation of the PPO enzyme by inducing aggregation and structural modifications. © 2019 Society of Chemical Industry [ABSTRACT FROM AUTHOR]

Isoflavones are one group of the major flavonoids and possess multiple biological activities due to their antioxidant properties. However, a clear antioxidant mechanism of dietary isoflavones is still remained to be answered. In this study, the effects of isoflavones on the nuclear factor E2‐related factor 2 (Nrf2)–antioxidant response element (ARE) signaling pathway and the underlying molecular mechanisms were investigated. Results showed that isoflavones are potential Nrf2–ARE activators while their activities were structure dependent. Biochanin A (BCA), an O‐methylated isoflavone with low direct antioxidant activity, can effectively protect HepG2 cells against tert‐butyl hydroperoxide (t‐BHP)‐induced oxidative damage via activation of the Nrf2 signaling, and thereby the induction of downstream cytoprotective enzymes including NAD(P)H quinone oxidoreductase‐1, heme oxygenasae‐1, and glutamate‐cysteine ligase catalytic subunit. A molecular docking study revealed that BCA could directly bind into the pocket of Kelch‐like erythroid cell‐derived protein with CNC homology (ECH)‐associated protein 1 (Keap1), a cytoplasmic suppressor of Nrf2, to facilitate Nrf2 activation. The upstream mitogen‐activated protein kinase (MAPK) pathways were also involved in the activation of Nrf2 signaling. These findings indicate that the protective actions of dietary isoflavones against oxidative damage may be at least partly due to their ability to enhance the intracellular antioxidant response system by modulating the Nrf2−ARE signaling pathway. [ABSTRACT FROM AUTHOR]

Many neurodegenerative disorders, such as Parkinson's disease ( PD), are characterized by progressive neuronal loss in different regions of the central nervous system, contributing to brain dysfunction in the relevant patients. Stem cell therapy holds great promise for PD patients, including with foetal ventral mesencephalic cells, human embryonic stem cells ( hESCs) and human induced pluripotent stem cells (hi PSCs). Moreover, stem cells can be used to model neurodegenerative diseases in order to screen potential medication and explore their mechanisms of disease. However, related ethical issues, immunological rejection and lack of canonical grafting protocols limit common clinical use of stem cells. iPSCs, derived from reprogrammed somatic cells, provide new hope for cell replacement therapy. In this review, recent development in stem cell treatment for PD, using hi PSCs, as well as the potential value of hi PSCs in modelling for PD, have been summarized for application of iPSCs technology to clinical translation for PD treatment. [ABSTRACT FROM AUTHOR]

Potato pulp was pretreated through the process of microwave and ultrasonic wave before they were hydrolyzed by cellulose. They were pretreated with microwave power of 240 W at microwave time of 7 min and with ultrasonic wave power of 200 W at ultrasonic wave time of 10 min, respectively. The reduction in sugar and glucose content in pretreated specimens under both pretreated conditions were measured by biotransformation method; the experimental results indicated that both the microwave and ultrasonic wave treatment could lead to significant improvement in sugar production, including reducing sugar and glucose, which provided potential strategies for widening practical application of potato pulp in the food industry. Practical Applications Energy and environment problems can be meaningfully addressed by fully using the by-products of the agricultural products processing industry. And this research is also of practical relevance with regard to the biofuel industry. In this study, use of microwave and ultrasonic wave pretreatment could lead to significant improvement in sugar production, including sugar and glucose reduction, which means improvements in production yield and reductions in production costs. And this also provides potential strategies for widening practical application of potato pulp and some other by-products of the agricultural products processing industry. [ABSTRACT FROM AUTHOR]

High hydrostatic pressure (HHP) has been widely used in various industries, and the protein as one of the most noticeable bio‐macromolecules has exhibited distinct structural and functional characteristics under HHP conditions. In this work, steered molecular dynamics (SMD) simulations of β‐lactoglobulin (βlg) are exploited to investigate the flexibility of the individual secondary structural element of the polypeptide. The two loops and the two helices on the two sides of the molecular β‐barrel are found to be highly flexible and migrate toward the hydrophobic interior of the protein at relatively low pressures. Interestingly, there is evidence illustrating that water penetrations only occur from the loop‐side of the barrel under pressurizations, which is favored by the enlarged β‐barrel induced through the loop compression. Moreover, increased stability of βlg is attributed to the rigid regions of the protein molecule. N‐ and C‐termini of the polypeptide chain are also found to be of great importance to pressure‐induced unfolding of βlg. It is found the modeling results agree with previous experimental observations, demonstrating the validity of the applications of SMD for studies on pressure‐induced protein unfolding. Such methodology will provide new insight into HHP and be generalized for more complicated systems such as enzymes. [ABSTRACT FROM AUTHOR]