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[Display omitted] • A bioplastic was synthesized from citrus peel biomass. • Bioplastic is safely degradable and recyclable, enabling a perfect closed-loop cycle. • Bioplastics exhibit unique antioxidant and antimicrobial properties. • Bioplastics can extend the shelf life of perishable fruits. • The universality of this strategy was validated in a wide range of fruit peels. The development of biodegradable antimicrobial bioplastics for food packaging holds great promise for solving the pollution and safety problems caused by petrochemical plastics and spoiled food. Herein, a natural active-bioplastic synthesized from citrus peel biomass is presented for perishable fruit preservation. These plastics are characterized by the nanoscale entanglement and recombinant hydrogen bonding between the endogenous pectin, polyphenols and cellulose micro/nanofibrils. They have attractive flexibility, tensile strength, gas barrier properties and antimicrobial activities, and can effectively extend the shelf life of perishable fruits such as banana and mango when used as food packaging. Cytotoxicity, degradability tests and life-cycle assessment show that these plastics had excellent nontoxicity and can be safely degraded or easily recycled. This work demonstrates a sustainable strategy for converting peel waste into eco-friendly bioplastics, providing a unique and novel insight into radically reducing the pollution and life-health threats posed by petrochemical plastics and spoiled food. [ABSTRACT FROM AUTHOR]

In this work, pectin-lignin nanoparticle (LNP) composite films were prepared, the physical, antioxidant and antibacterial properties of the films systematically evaluated. The LNP were compatible with the pectin matrix, and the tensile strength (TS) and water contact angle (WCA) of the pectin-based films were enhanced by 164% and 56% at the optimum LNP loading of 3.0% (w/w). The results of dynamic WCA demonstrate the hydrophobic stability of pectin-LNP composite films. Even trace amounts of LNP (1.0%, w/w) were found to significantly improve the mechanical properties (TS improved 67.33%), hydrophobicity (WCA improved 48.83), and water barrier properties (the water vapor permeability decreased by 25.30%) of the pectin-based films. The tight entanglement and strong positive interaction between pectin and LNP promote the formation of dense structures, which is beneficial to the film properties. In addition, all pectin-LNP composite films almost completely shield the UVB (320-275 nm) and UVC (275-200 nm) spectrum, along with most of the UVA (400–320 nm) spectrum, which demonstrates their strong anti-ultraviolet performance. In terms of bioactivity, the addition of LNP significantly enhanced the DPPH radical scavenging ability (maximum boost is 6.33 times) and antibacterial ability (maximum inhibition rate was 78.79 for S.aureus and 47.80% for E.coli) of the pectin film. These results suggest that the pectin-LNP composite film are promising active packaging materials for food preservation/packaging applications. [Display omitted] • Pectin-lignin nanoparticle (LNPs) composite films were prepared. • LNPs were uniformly dispersed in pectin-based films (high compatibility). • LNPs addition enhanced the mechanical and hydrophobic properties of pectin films. • The composite films showed good anti-UV, antioxidant, and antibacterial activities. • The composite films have great potential for active food packaging. [ABSTRACT FROM AUTHOR]

Abstract: Endoplasmic reticulum (ER) is crucial for protein folding, glycosylation and secretion in eukaryotic organisms. These important functions are supported by high levels of Ca2+ in the ER. We have recently identified a putative ER Ca2+ pump in Candida albicans, called Spf1, which plays key roles in maintenance of cellular Ca2+ homeostasis, morphogenesis and virulence. In this study, we purified Spf1 and confirmed that it is a P-type ATPase, suggesting its role in maintaining high levels of ER Ca2+. Disruption of SPF1 caused severe defects in glycosylation of the ER-localized protein Cdc101 and secretory acid phosphatase, and a decrease in expression of SEC61 which encodes an important ER protein. Moreover, the spf1Δ/Δ mutant showed increased sensitivity to cell wall stresses, abnormal cell wall composition, delayed cell wall reconstruction and decreased flocculation and adherence, indicating its defect in cell wall integrity (CWI). We also revealed that disruption of SPF1 has an impact on gene expression related to CWI and morphogenesis. This study provides evidence that Spf1, as a P-type ATPase, is essential for ER functions and consequent CWI, implicating a role of ER Ca2+ homeostasis in C. albicans physiology. [Copyright &y& Elsevier]

Alterations in zinc transporter expression in response to zinc loss protect cardiac cells from ischemia/reperfusion (I/R) injury. However, the underlying molecular mechanisms how cardiac cells sense zinc loss remains unclear. Here, we found that zinc deficiency induced ubiquitination and degradation of the protein inhibitor of activated STAT3 (PIAS3), which can alleviate myocardial I/R injury by activating STAT3 to promote the expression of ZIP family zinc transporter genes. The RING finger domain within PIAS3 is vital for PIAS3 degradation, as PIAS3-dRing (missing the RING domain) and PIAS3-Mut (zinc-binding site mutation) were resistant to degradation in the setting of zinc deficiency. Meanwhile, the RING finger domain within PIAS3 is critical for the inhibition of STAT3 activation. Moreover, PIAS3 knockdown increased cardiac Zn2+ levels and reduced myocardial infarction in mouse hearts subjected to I/R, whereas wild-type PIAS3 overexpression, but not PIAS3-Mut, reduced cardiac Zn2+ levels, and exacerbated myocardial infarction. These findings elucidate a unique mechanism of zinc sensing, showing that fast degradation of the zinc-binding regulatory protein PIAS3 during zinc deficiency can correct zinc dyshomeostasis and alleviate reperfusion injury. [Display omitted] • Zinc deficiency induces the activation of STAT3, which acts as a transcription factor to promote upregulation of ZIP family zinc transporter gene expression, thereby compensating for Zn2+ loss. • PIAS3 can sense intracellular Zn2+ deficiency through its ubiquitination-mediated degradation and regulate the activity of STAT3. • Ring finger domain plays a critical role in PIAS3's ubiquitination and degradation by releasing Zn2+ in response to Zn2+ deficiency. • Knockdown of PIAS3 protected mouse hearts from I/R injury, whereas overexpression of PIAS3 exacerbated injury. [ABSTRACT FROM AUTHOR]

Most diseases have multiple pathogenic strains, which may impose difficulty in combatting the disease and lead to rich dynamics. However, their dynamical properties are not well understood. For this purpose, we formulate and analyze a two-strain SIS epidemic model with a competing mechanism and general infection force on complex networks. We derive the basic reproduction number and introduce the invasion reproduction numbers for each strain. We demonstrate that if R 0 < 1 , the disease-free equilibrium is globally asymptotically stable, i.e., the disease will die out. If R 0 > 1 , the conditions of the existence and global asymptotical stability of dominant equilibria are further studied. The persistence of the system is also addressed. Numerical simulations are given to illustrate the theoretical results. [ABSTRACT FROM AUTHOR]

A non-intrusive, in-situ detection technique for combustion intermediates in flame environments yields highly resolved spectra that are largely insensitive to molecular vibrations and thus temperature. The technique is based on laser photoionization of target compounds via Rydberg states, followed by detection of the laser-induced plasma with microwave radiation. The feasibility of this approach is tested on methyl radicals that are detected in methane, propane, and hexane fuel-rich flames. The methyl radicals are prepared in the 3s Rydberg state using photoexcitation at 216.4 nm. Using tunable VIS/IR radiation, the molecules are promoted from 3s to the 3p xy and 3p z Rydberg states. Photoionization out of the 3p states with 355 nm photons results in a small-volume plasma that is detected by microwave backscattering. The previously unobserved 3pxy state is found to have a binding energy of 2.57 eV. [ABSTRACT FROM AUTHOR]

Deoxynivalenol (DON) is the most abundant mycotoxin in cereal crops and derived foods and is of great concern in agriculture. Bioremediation strategies have long been sought to minimize the impact of mycotoxin contamination, but few direct and effective enzyme-catalyzed detoxification methods are currently available. In this study, we established a multi-enzymatic cascade reaction and successfully achieved detoxification at double sites: glutathionylation for the C-12,13 epoxide group and epimerization for the C-3 hydroxyl group. This yielded novel derivatives of DON, 3- epi -DON-13-glutathione (3- epi -DON-13-GSH) as well as its by-product, 3-keto-DON-13-GSH, for which precise structures were validated via liquid chromatography–high-resolution tandem mass spectrometry (LC-HRMS) and nuclear magnetic resonance (NMR) spectroscopy. Both cell viability and DNA synthesis assays demonstrated dramatically decreased cytotoxicity of the double-site modified product 3- epi -DON-13-GSH. These findings provide a promising and urgently needed novel method for addressing the problem of DON contamination in agricultural and industrial settings. [Display omitted] • Establishment of a multi-enzyme cascade reaction for the detoxification of DON • Achieved structural characterization of the double-site modified products of DON • DON toxicity dramatically decreased after glutathionylation and epimerization [ABSTRACT FROM AUTHOR]

Abstract: Iron bioavailability is crucial for mitochondrial metabolism and biosynthesis. Dysregulation of cellular iron homeostasis affects multiple aspects of mitochondrial physiology and cellular processes. However, the intracellular iron trafficking pathway in Candida albicans remains unclear. In this study, we characterized the Mrs4–Ccc1–Smf3 pathway, and demonstrated its important role in maintaining cellular iron levels. Double deletion of vacuolar iron exporter SMF3 and mitochondrial iron transporter MRS4 further elevated cellular iron levels in comparison with the single MRS4 deletion. However, deletion of vacuolar iron importer CCC1 in the mrs4∆/∆ mutant restored cellular iron homeostasis to normal wild-type levels, and also normalized most of the defective phenotypes in response to various environmental stresses. Our results also suggested that both Mrs4 and Ccc1 contributed to the maintenance of mitochondrial function. The mrs4∆/∆ and mrs4∆/∆smf3∆/∆ mutants exhibited an obvious decrease in aconitase activities and mitochondrial membrane potential, whereas deletion of CCC1 in the mrs4∆/∆ mutant effectively rescued these defects. Furthermore, we also found that the Mrs4–Ccc1–Smf3 pathway was indispensable for cell-wall stability, antifungal drug tolerance, filamentous growth and virulence, supporting the novel viewpoint that mitochondria might be the promising target for better antifungal therapies. Interestingly, the addition of exogenous iron failed to rescue the defects on non-fermentable carbon sources or hyphae-inducing medium, indicating that the defects in mitochondrial respiration and filamentous development might result from the disturbance of cellular iron homeostasis rather than environmental iron deprivation. Taken together, our results propose the Mrs4–Ccc1–Smf3 pathway as a potentially attractive target for antifungal drug development. [Copyright &y& Elsevier]

The high brittleness, susceptibility to moisture absorption and low biological activity of pectin films limit their development. To address these limitations, carboxylated cellulose nanocrystals-stabilized oregano essential oil Pickering emulsion (COPE) was prepared to activate pectin films. COPE has good compatibility, and it can be uniformly dispersed in pectin matrix, which promotes the stable formation of composite films characterized by tight entanglement and hydrogen bonding between COPE and pectin molecules. Compared with pure pectin film, pectin-COPE composite film shows higher tensile strength (16.03 MPa), elongation at break (25.27%), water contact angle (88.02°) and lower water vapor permeability (1.40 × 10−10 g/m·s·Pa). Importantly, COPE endows pectin film with unique anti-ultraviolet (composite film almost completely blocks light in the UVC (275-200 nm) and UVB (320-275 nm) regions, as well as most light in the UVA (400-320 nm) region), antioxidation (DPPH radical scavenging capacity and T-AOC were maximized by 4.53% and 2.72%, respectively) and antibacterial properties (a clear ring of inhibition appears around the composite film), allowing it to significantly extend the shelf life and maintain the quality of cherries when used for packaging. In conclusion, COPE offers novel strategies to enhance the bioactive, mechanical and hydrophobic properties of pectin-based films, and the pectin-based composite films activated by COPE can provide more opportunities for food preservation/packaging as potential petrochemical plastic substitutes. [Display omitted] • Carboxylated cellulose nanocrystals (C–CNCs) were obtained by periodate oxidation. • C-CNCs-stabilized Pickering emulsions of essential oils (COPE) were prepared. • COPE has good biocompatibility and can be used to activate pectin-based films. • The performance of the activated film is significantly enhanced and exhibits unique bioactivities. • The activated films have great potential for producing active food packaging/coating. [ABSTRACT FROM AUTHOR]

[Display omitted] • Toxicity of trichothecene-13-glutathione adducts was dramatically decreased. • Glutathione epoxide adduct not metabolized back to free toxin during digestion. • First discovery of an enzymatic degradation pathway for macrocyclic trichothecenes. Trichothecene (TCN) contamination in food and feed is a serious challenge due to the negative health and economic impacts. Here, we confirmed that the glutathione S-transferase (GST) Fhb7-GST could broadly catalyze type A, type B and type D TCNs into glutathione epoxide adducts (TCN-13-GSHs). To evaluate the toxicity of TCN-13-GSH adducts, we performed cell proliferation assays in vitro , which demonstrated decreased cytotoxicity of the adducts. Moreover, in vivo assays (repeated-dose treatment in mice) confirmed that TCN-13-GSH adducts were dramatically less toxic than the corresponding TCNs. To establish whether TCN-13-GSH was metabolized back to free toxin during digestion, single-dose metabolic tests were performed in rats; DON-13-GSH was not hydrolyzed in vivo , but rather was quickly metabolized to another low-toxicity compound, DON-13- N -acetylcysteine. These results demonstrate the promise of Fhb7-GST as a candidate of detoxification enzyme potentially applied in TCN-contaminated agricultural samples, minimizing the detrimental effects of the mycotoxin. [ABSTRACT FROM AUTHOR]

[Display omitted] • The starches of three new varieties of corn cultivated by our team were investigated. • The structure and properties of 8 kinds of waxy, sweet waxy corn starch were studied. • The corn varieties that could replace waxy rice development products were identified. To explore the feasibility of substituting waxy rice with waxy or sweet-waxy corn, eight varieties of waxy and sweet-waxy corns were selected, including three self-cultivated varieties (Feng nuo 168, Feng nuo 211, and Feng nuo 10). Their starches were isolated and used as research objects, and commercially available waxy rice starch (CAWR) and waxy corn starch (CAWC) were used as controls. X-ray diffraction, scanning electron microscopy, differential scanning calorimetry, rapid viscosity analyzer, and rotational rheometer were used to analyze their physicochemical and structural characteristics. The morphologies of all corn starch granules were generally oval or round, with significant differences in particle size distributions. All ten starches exhibited a typical A-type crystal structure; however, their relative crystallinity varied from 20.08% to 31.43%. Chain length distribution analysis showed that the A/B ratio of Jing cai tian nuo 18 and Feng nuo 168 was similar to that of CAWR. Peak viscosities of corn starches were higher than that of CAWR, except for Feng nuo 10, while their setback values were lower than that of CAWR. Except for Feng nuo 10, the paste transparency of corn starches was higher than that of CAWR (10.77%), especially for Jing cai tian nuo 18 (up to 24%). In summary, Jing cai tian nuo 18 and Feng nuo 168 are promising candidates to replace CAWR in developing various rice-based products. [ABSTRACT FROM AUTHOR]

Polym. Corrigendum to "Physicochemical characterization and emulsifying properties evaluation of RG-I enriched pectic polysaccharides from Cerasus humilis" [Carbohydr. [Extracted from the article]

[Display omitted] • RG-I enriched pectic polysaccharides extracted from Cerasus humilis fruits (RPCF). • RPCF is a high-methoxy acetylated pectin. • RPCF forms a weak gel network that stabilizes the emulsions. • RPCF can provide additional oxidation stability to the internal-phase of emulsion. • RPCF demonstrates potential in forming sugar-free gel systems. Rhamnogalacturonan I (RG-I) enriched pectic polysaccharides were extracted from Cerasus humilis fruits (RPCF, RG-I: 74.46 %). Structural characterization including FTIR, XRD, NMR, HPAEC and SEM demonstrated that RPCF was a high-methoxy acetylated pectin macromolecule with abundant arabinose and galactose side chains (DM: 53.41 %, MW: 1098 kDa, (Ara + Gal)/Rha: 5.37 %). RPCF afforded additional lipid oxidation stability for emulsions, and exhibited significantly better emulsification performance than citrus pectin. In addition, RPCF formed a weak gel network that stabilized the emulsions (G′ > G″). Interestingly, RPCF had behaviors that are divergent from those of commercial high-methoxy pectin because it demonstrated potential in forming sugar-free gels systems. Overall, Cerasus humilis is a new source of pectin rich in RG-I. RPCF can be used as a novel emulsifier with gelling and antioxidant effects, providing its alternative application as a natural emulsifier and rheological modifier in a wide range of products, including those with oil-in-water and low sugar. [ABSTRACT FROM AUTHOR]