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A new ordered assembled porous C 3 N 4 /reduced graphene oxide/TiO 2 nanobelts (CRT) was used to degrade 17α-ethinylestradiol (EE2) via photocatalysis, activation of peroxydisulfate (PS) in dark and under visible light irradiation. The singlet oxygen (1O 2) and direct electron transfer process existed in CRT/PS/Dark process and superoxide radicals (•O 2 –) and holes (h+) generated in photocatalysis, and synergetic effect of nonradical (h+, 1O 2 and direct electron transfer route) and radical processes (•O 2 –) was responsible for the rapid degradation of EE2 in CRT/PS/Vis process. [Display omitted] • A novel porous g-C 3 N 4 /reduced graphene oxide/TiO 2 nanobelts was assembled. • 17α-ethinylestradiol degradation rate in CRT/PS/Vis was 207.51 times than photocatalysis. • Less PS amount were needed in CRT/PS/Visible light system. • The synergetic effect of radical and non-radical activation existed in PS/CRT/Vis. • Degradation products were identified and degradation pathways were proposed. A new porous C 3 N 4 /reduced graphene oxide/TiO 2 nanobelt catalyst (CRT) was assembled and used to remove 17α-ethinylestradiol (EE2) in the presence of peroxydisulfate (PS) and visible light. The characterization results showed that larger porous graphite carbon nitrides (pg-C 3 N 4) covered onto the surface of TiO 2 /reduced graphene oxide (RGO), in which layered RGO was wrapped onto the surface of anatase TiO 2 nanobelt uniformly. The layered RGO in CRT played significant role in separation of electron-hole pairs and nonradical activation. The electron paramagnetic resonance and quenching experiment revealed that h+, 1O 2 and •O 2 – and direct electron transfer route contributed to complete removal of 6 mg/L EE2 within 6 min only with 0.5 g/L dosage and 1 mM PS. The degradation rate of EE2 in CRT/PS/Vis was 207.51 times than that in photocatalysis. The degradation products were identified by a solid phase extraction pretreatment method combined with ultra-high-performance liquid chromatography-mass spectrometry, and possible degradation pathways were proposed. Moreover, the estrogenic activities can be rapidly eliminated in CRT/PS/Vis process. [ABSTRACT FROM AUTHOR]

In the past 20 years, the global per capita protein demand has been increasing year by year, and thus the search for sustainable and healthier alternative proteins is the focus of current food research. Yeast proteins are of microbial origin with environmentally friendly advantages. They are high-quality proteins with high bioavailability and are expected to be used as novel alternative proteins for food applications. Although reports on yeast extracts continue to increase, studies on the composition, production methods, and functional properties of yeast proteins lack systematic reviews. In addition, the application of yeast proteins in the food industry has not been summarized previously. This paper reviews the composition of yeast proteins and the approaches for their isolation and extraction, and systematically introduces the functional properties and the wide applications in food fields. Future perspectives for yeast proteins to sustainably and healthily meet the world's growing protein demand are also elucidated. Yeast proteins have great application potential as alternative proteins with a reasonable proportion of amino acid composition. Yeast proteins can be hydrolyzed to produce yeast peptides and can also be used as protein supplements, fining agents, meat extenders, etc. Overcoming the limitations of high nucleic acid content and high cost, and improving the functional properties and sensory acceptability of yeast proteins will greatly promote their market applications. This review will provide ideas and guidance for the research and development of yeast proteins in food applications. Yeast proteins have high nutritional value with an ideal amino acid composition and a wealth of functions and properties. The excellent characteristics allow yeast proteins to be used as sustainable alternative proteins in food applications. [Display omitted] • The compositions and extraction approaches of yeast proteins are overviewed. • The functional properties of yeast proteins are summarized. • The applications of yeast proteins as alternative proteins in food are reviewed. • The strategies to improve the utilization of yeast proteins are emphasized. [ABSTRACT FROM AUTHOR]

Abstract: Background: 1-Aminocyclopropane-1-carboxylate oxidase (ACO) is a key enzyme that catalyses the final step in the biosynthesis of the plant hormone ethylene. Recently, the first ACO homologue gene was isolated in Agaricus bisporus, whereas information concerning the nature of the ethylene-forming activity of this mushroom ACO is currently lacking. Methods: Recombinant ACO from A. bisporus (Ab-ACO) was purified and characterised for the first time. Molecular modelling combined with site-directed mutagenesis and kinetic and spectral analysis were used to investigate the property of Ab-ACO. Results: Ab-ACO has eight amino acid residues that are conserved in the Fe (II) ascorbate family of dioxygenases, including four catalytic residues in the active site, but Ab-ACO lacks a key residue, S289. In comparison to plant ACOs, Ab-ACO requires ACC and Fe (II) but does not require ascorbate. In addition, Ab-ACO had relatively low activity and was completely dependent on bicarbonate, which could be ascribed to the replacement of S289 by G289. Moreover, the ferrous ion could induce a change in the tertiary, but not the secondary, structure of Ab-ACO. Conclusions: These results provide crucial experimental support for the ability of Ab-ACO to catalyse ethylene formation in a similar manner to that of plant ACOs, but there are differences between the biochemical and catalytic characteristics of Ab-ACO and plant ACOs. General significance: This work enhances the understanding of the ethylene biosynthesis pathways in fungi and could promote profound physiological research of the role of ethylene in the regulation of mushroom growth and development. [Copyright &y& Elsevier]

• Succinylation was applied to modify the apo-red bean seed ferritin (apoRBF). • The cage-like structure and self-assembly of the succinylated apoRBF were retained. • The physicochemical properties of the succinylated apoRBF were changed. • Succinylated apoRBF encapsulated the EGCG and enhanced its stability and absorption. Ferritin, a protein with an 8-nm cage structure, can encapsulate and deliver bioactive molecules. In this study, succinylation was adopted to modify plant ferritin to fabricate succinylated red been ferritin (SRBF) at pH 8.0. The SRBF was retained as a cage-like shape (12 nm diameter), while its secondary structure was altered, rendering higher negative charge accompanies by decreased surface hydrophobicity. The SRBF also demonstrated favorable property of reversible assembly regulated by pH-transitions (pH 2.0/7.0), thus enabled successful encapsulation of epigallocatechin gallate (EGCG) for fabrication of EGCG-loaded SRBF complexes with a diameter of ~12 nm. Succinylation enhanced the thermal stabilities of ferritin and the embedded EGCG. Moreover, SRBF markedly improved the transport efficiency of EGCG in Caco-2 monolayers relative to EGCG and that encapsulated in unmodified ferritin. These findings have extended the succinylation reaction for the cage-like protein modification, and facilitated the usage of ferritin variant in delivery of bioactive molecules. [ABSTRACT FROM AUTHOR]

SUMMARY: Ripening is the last, irreversible developmental stage during which fruit become palatable, thus promoting seed dispersal by frugivory. In Alisa Craig fruit, mRNAs with increasing m5C levels, such as STPK and WRKY 40, were identified as being involved in response to biotic and abiotic stresses. Furthermore, two mRNAs involved in cell wall metabolism, PG and EXP‐B1, also presented increased m5C levels. In the Nr mutant, several m5C‐modified mRNAs involved in fruit ripening, including those encoding WRKY and MADS‐box proteins, were found. Targets of long non‐coding RNAs and circular RNAs with different m5C sites were also found; these targets included 2‐alkenal reductase, soluble starch synthase 1, WRKY, MADS‐box, and F‐box/ketch‐repeat protein SKIP11. A combined analysis of changes in 5mC methylation and mRNA revealed many differentially expressed genes with differentially methylated regions encoding transcription factors and key enzymes related to ethylene biosynthesis and signal transduction; these included ERF084, EIN3, AP2/ERF, ACO5, ACS7, EIN3/4, EBF1, MADS‐box, AP2/ERF, and ETR1. Taken together, our findings contribute to the global understanding of the mechanisms underlying fruit ripening, thereby providing new information for both fruit and post‐harvest behavior. Significance Statement: This is the first study on the regulation of RNA (m5C) methylation and non‐coding RNA (m5C) methylation on tomato fruit ripening in the world, which will establish a great foundation for tomato breeding and fresh fruit ripening regulation research. [ABSTRACT FROM AUTHOR]

Leguminous proteins are important nutritional components in leguminous plants, and they have different structures and functions depending on their sources. Due to their specific structures and physicochemical properties, leguminous proteins have received much attention in food and nutritional applications, and they can be applied as various carriers for binding/encapsulation and delivery of food bioactive compounds. In this review, we systematically summarize the different structures and functional properties of several leguminous proteins which can be classified as ferritin, trypsin inhibitor, β-conglycinin, glycinin, and various leguminous proteins isolates. Moreover, we review the development of leguminous proteins as carriers of food bioactive compounds, and emphasize the functions of leguminous protein-based binding/encapsulation and delivery in overcoming the low bioavailability, instability and low absorption efficiency of food bioactive compounds. The limitations and challenges of the utilization of leguminous proteins as carriers of food bioactive compounds are also discussed. Possible approaches to resolve the limitations of applying leguminous proteins such as instability of proteins and poor absorption of bioactive compounds are recommended. [ABSTRACT FROM AUTHOR]

Cowpea (Vigna unguiculata (L.) Walp) is prone to water loss and shriveling after harvest. Sodium nitroprusside (SNP) as a generator of nitric oxide acts as a senescence retarding agent. In this study, the influence of SNP on cowpea senescence during storage at 15 °C for 8 d has been investigated. SNP treatment (0.3 mM) decreased the mass loss and maintained the hardness, total chlorophyll, and vitamin C content of the cowpeas. SNP suppressed the expression of the genes involved in ethylene signaling (SAM1 , ETR2 , ERFs), cell wall disassembly (PE2 , PL5 , PG), and the lignin synthesis genes (4CL , CCR , and CAD), while inducing the expression of defense and resistance-related genes (KCS , ABCG , BAK1 , PR-4 , and CpPR3). The major differentially accumulated metabolites in SNP-treated cowpeas were flavonoids, phenolic acids, and alkaloids. SNP-induced differentially expressed proteins that are involved in lignification (4CL, CAD, and POD), texture-related processes (PL5, PE, and EG), and disease resistance (PBSI, PR1, and SCP). Overall, the study revealed that SNP-generated NO suppressed ethylene signaling, inhibited lignin accumulation, regulated wax, suberin, and cuticle biosynthesis, and enhanced defense processes, resulting in higher-quality cowpeas than those of the untreated controls. [Display omitted] • SNP treatment decreased ethylene signal transduction of cowpeas. • SNP treatment maintained hardness and delayed lignification in cowpeas. • SNP treatment inhibited the cutin, suberin, and wax biosynthesis pathways. • SNP treatment enhanced defense reactions and the levels of disease-resistance substances. [ABSTRACT FROM AUTHOR]

Currently, the use of synthetic pigments in foods is restricted since synthetic pigments are proven and suspected to be harmful to human health. Phycobiliproteins (PBPs), existed in phycobilisomes (PBSs) of algae, are a kind of pigment-proteins with intense color. The specific color of PBPs (red and blue) is given by the water-soluble open-chained tetrapyrrole chromophore (phycobilin) that covalently attaches to the apo-protein via thioether linkages to cysteine residues. According to the spectral characteristics of PBPs, they can be categorized as phycoerythrins (PEs), phycocyanins (PCs), allophycocyanins (APCs), and phycoerythrocyanins (PECs). PBPs can be used as natural food colorants, fluorescent substances, and bioactive ingredients in food applications owing to their color characteristics and physiological activities. This paper mainly summarizes the extraction and purification methods of the PBPs and reviews their characteristics and applications. Moreover, the use of several strategies such as additives, microencapsulation, electrospray, and cross-linking to improve the stability and bioavailability of PBPs as well as the future outlooks of PBPs as natural colorants in food commercialization are elucidated. [ABSTRACT FROM AUTHOR]

Ferritin is characterized by a shell-like structure and a reversible self-assembly property. In this study, atmospheric cold plasma (ACP) was applied to red bean seed ferritin (RBF) to prepare an ACP-treated RBF (ACPF). Results indicated that the ACP treatment retained the shell-like structure of ferritin but reduced the α-helix/β-sheet contents and thermal stability. Iron oxidative deposition and release activities were also markedly changed. The ACPF could be disassembled at pH 4.0 and then assembled into an intact ferritin cage when pH was increased to 7.0, which was a more benign transition condition than that of the traditional method (pH 2.0/7.0 transition). By using this assembly routine, curcumin was successfully encapsulated within the ACPF with a size distribution of 12 nm. Moreover, the encapsulation ratio of curcumin in the ACPF reached 12.7% (w/w). This finding can be used to expand the application of ACP and improve the functionalization of the ferritin. [ABSTRACT FROM AUTHOR]

The increasing incidence and rapid spread of bacterial resistance to conventional antibiotics are a serious global threat to public health, highlighting the need to develop new antimicrobial alternatives. Antimicrobial peptides (AMPs) represent a class of promising natural antibiotic candidates due to their broad-spectrum activity and low tendency to induce resistance. However, the development of AMPs for medical use is hampered by several obstacles, such as moderate activity, lability to proteolytic degradation, and low bioavailability. To date, many researchers have focussed on the optimization or design of novel artificial AMPs with desired properties. Unnatural amino acids (UAAs) are valuable building blocks in the manufacture of a variety of pharmaceuticals, and have been used to develop artificial AMPs with specific structural and physicochemical properties. Rational incorporation of UAAs has become a very promising approach to endow AMPs with strong and long-lasting activity but no toxicity. This review aims to summarize key approaches that have been used to incorporate UAAs to develop novel AMPs with improved properties and better performance. It is anticipated that this review will guide future design considerations for UAA-based antimicrobial applications. [ABSTRACT FROM AUTHOR]

Basic helix-loop-helix (bHLH) transcription factors (TFs) are widely distributed in eukaryotes and play an important role in biological growth and development. The identification and functional analyses of bHLH genes/proteins in edible mushrooms (Agaricus bisporus) have yet to be reported. In the present study, we identified 10 putative bHLH members carrying the conserved bHLH domains. Phylogenetic analyses revealed that the 10 AbbHLHs were the closest to sequences of species belonging to 7 different fungal subgroups, which was supported by loop length, intron patterns, and key amino acid residues. The substantial increase after harvest and continuously elevated expression of AbbHLH1 during the development until the disruption of mushroom velum, and the preferential expression in cap and gill tissues suggest the important function of AbbHLH1 in postharvest development of A. bisporus. The relationship of arginine catabolism-related genes with the early stage of postharvest continuing development also was revealed by expression determination. Subcellular localization showed that AbbHLH1 could be localized in nucleus. Importantly, the electrophoretic mobility shift and dual-luciferase reporter assays showed that AbbHLH1 activated the promoters of AbOAT , AbSPDS , and AbSAMDC and suppressed the expression of AbARG , AbUREA , and AbODC , probably for the modulation of arginine catabolism and thus control of postharvest mushroom development. Taken together, the available data provide valuable functional insight into the role of AbbHLH proteins in postharvest mushrooms. • Ten bHLH genes were firstly identified in edible mushrooms (Agaricus bisporus). • AbbHLH1 was a potential regulator in the postharvest development of A. bisporus. • AbbHLH1 could be localized in nucleus. • AbbHLH1 directly bound to the promoters of arginine catabolism-related genes. • AbbHLH1 promoted/inhibited the promoters of arginine catabolism-related genes. [ABSTRACT FROM AUTHOR]

[Display omitted] • The ultrasound-induced fabrication of the YCB by was studied. • Ultrasound improved the surface hydrophobicity and solubility of yeast protein. • Ultrasound facilitated binding of betanin and oligosaccharide to the yeast protein. • YCB exhibits a high color stability of betanin and controls its sustained release. • This work offers a scheme to stabilize colorant by an ultrasound-assisted method. Betanin, a water-soluble colorant, is sensitive to light and temperature and is easily faded and inactivated. This study investigated the formation of yeast protein-chitooligosaccharide-betanin complex (YCB) induced by ultrasound treatment, and evaluated its protective effect on the colorant betanin. Ultrasound (200–600 W) increased the surface hydrophobicity and solubility of yeast protein, and influenced the protein's secondary structure by decreasing the α-helix content and increasing the contents of β-sheet and random coil. The ultrasound treatment (200 W, 15 min) facilitated binding of chitooligosaccharide and betanin to the protein, with the binding numbers of 4.26 ± 0.51 and 0.61 ± 0.06, and the binding constant of (2.73 ± 0.25) × 105 M−1 and (3.92 ± 0.10) × 104 M−1, respectively. YCB could remain the typical color of betanin, and led to a smaller and disordered granule morphology. Moreover, YCB exhibited enhanced thermal-, light-, and metal irons (ferric and copper ions) -stabilities of betanin, protected the betanin against color fading, and realized a controlled release in simulated gastrointestinal tract. This study extends the potential application of the fungal proteins for stabilizing bioactive molecules. [ABSTRACT FROM AUTHOR]

The natural antimicrobial peptide, epsilon-poly- l -lysine (ε-PL), is widely acknowledged as a food preservative. However, its potential in managing bacterial brown blotch disease in postharvest edible mushrooms and the associated mechanism remain unexplored. In this study, concentrations of ε-PL ≥ 150 mg L−1 demonstrated significant inhibition effects, restraining over 80% of growth and killed over 99% of Pseudomonas tolaasii (P. tolaasii). This inhibition effect occurred in a concentration-dependent manner. The in vivo findings revealed that treatment with 150 mg L−1 ε-PL effectively inhibited P. tolaasii -caused brown blotch disease in Agaricus bisporus (A. bisporus) mushrooms. Plausible mechanisms underlying ε-PL's action against P. tolaasii in A. bisporus involve: (i) damaging the cell morphology and membrane integrity, and increasing uptake of propidium iodide and leakage of cellular components of P. tolaasii ; (ii) interaction with intracellular proteins and DNA of P. tolaasii ; (iii) inhibition of P. tolaasii -induced activation of polyphenol oxidase, elevation of antioxidative enzyme activities, stimulation of phenylpropanoid biosynthetic enzyme activities and metabolite production, and augmentation of pathogenesis-related protein contents in A. bisporus mushroom s. These findings suggest promising prospects for the application of ε-PL in controlling bacterial brown blotch disease in A. bisporus. [Display omitted] • ε-PL significantly inhibited the growth of Pseudomonas tolaasii in vitro. • ε-PL effectively reduced bacterial brown blotch disease in postharvest A. bisporus. • ε-PL disrupted membrane integrity and led to cellular leakage of P. tolaasii. • ε-PL could likely disturb intracellular DNA and proteins of P. tolaasii. • ε-PL induced disease resistance against P. tolaasii in postharvest A. bisporus. [ABSTRACT FROM AUTHOR]

[Display omitted] • MeJA differentially regulated arginine catabolism–related genes and proteins. • MeJA tissue-specifically regulated arginine catabolism–related genes and proteins. • MeJA-upregulated AbASS expression most likely occurred at the translational level. • Both arginine and ornithine contents were reduced after exposure to MeJA. • MeJA-regulated arginine catabolism correlated with free polyamine accumulation. Methyl jasmonate (MeJA)-regulated postharvest quality retention of Agaricus bisporus fruiting bodies is associated with arginine catabolism. However, the mechanism of MeJA-regulated arginine catabolism in edible mushrooms is still unclear. This study aimed to investigate the regulatory modes of MeJA on the expression of arginine catabolism–related genes and proteins in intact and different tissues of A. bisporus mushrooms during storage. Results showed that exogenous MeJA treatment activated endogenous JA biosynthesis in A. bisporus mushrooms, and differentially and tissue-specifically regulated the expression of arginine catabolism–related genes (AbARG , AbODC , AbSPE-SDH , AbSPDS , AbSAMDC, and AbASL) and proteins (AbARG, AbSPE-SDH, AbASL, and AbASS). MeJA caused no significant change in AbASS expression but resulted in a dramatic increase in AbASS protein level. Neither the expression of the AbSAMS gene nor the AbSAMS protein was conspicuously altered upon MeJA treatment. Additionally, MeJA reduced the contents of arginine and ornithine and induced the accumulation of free putrescine and spermidine, which was closely correlated with MeJA-regulated arginine catabolism–related genes and proteins. Hence, the results suggested that the differential and tissue-specific regulation of arginine catabolism–related genes and proteins by MeJA contributed to their selective involvement in the postharvest continuing development and quality retention of button mushrooms. [ABSTRACT FROM AUTHOR]

Ferritin is a cage-like protein with a modifiable exterior surface. In this study, transglutaminase was applied to catalyze the glycosylation of oligochitosan onto the apo-red bean seed ferritin (apoRBF) to fabricate an oligochitosan-modified apoRBF nanoparticle (OFN). Results indicated that the oligochitosan glycosylation retained the shell-like structure of ferritin and improved its thermal stability. The reversible assembly of OFN regulated by pH and urea transition was successfully retained. By using this assembly routine, rutin can be encapsulated within the OFN either by pH 2.0/7.0 transition or urea (8.0 M/0 M) transition, and the size distribution of rutin-loaded OFN was mainly about 12 nm. Moreover, the thermal stability of the rutin in the OFN was significantly improved as compared with that in apoRBF. The present study will be beneficial for extension of chitosan and Transglutaminase applications in protein modification, and will improve ferritin functionalization as a nanocarrier for food bioactive molecules. Image 1 • Transglutaminase facilitated the fabrication of oligochitosan-modified apoRBF. • The shell-like structure of oligochitosan-modified apoRBF was retained. • The reversible assembly character of oligochitosan-modified apoRBF was retained. • Rutin can be encapsulated in this modified ferritin with a high thermal stability. [ABSTRACT FROM AUTHOR]

Abstract: BACKGROUND: Postharvest diseases result in major losses in fruits. Tomato is susceptible to postharvest rot caused by Botrytis cinerea and is regarded as a good model system to study postharvest disease and quality deterioration in fruit. To develop a safe and effective technique to alleviate disease and maintain fruit quality, the effects of methyl salicylate (MeSA) and 1‐methylcyclopropene (1‐MCP) either separately or combined on quality and gray mold caused by B. cinerea in tomato fruit were investigated. RESULTS: The results showed that application of MeSA (0.05 mmol L−1) delayed fruit ripening and reduced gray mold. Compared with MeSA treatment, 1‐MCP (0.5 µL L−1) effectively delayed fruit ripening. Further, MeSA combined with 1‐MCP treatment was more effective in inhibiting fungal decay during storage than MeSA treatment alone. The combined treatment not only enhanced pathogenesis‐related protein 1 (PR1) expression, activities of defense enzymes and total phenolic content but also inhibited the increase in electrical conductivity and malondialdehyde content. The combined treatment was also more effective in retaining firmness, color change and titratable acidity content than MeSA treatment alone. CONCLUSION: MeSA combined with 1‐MCP treatment was a useful technique to maintain quality and alleviate gray mold in postharvest tomato fruit during storage. © 2018 Society of Chemical Industry [ABSTRACT FROM AUTHOR]

The inner surface and outer surface of ferritin cage provide interfaces for the encapsulation and delivery of food nutrients. Traditional methods to fabricate ferritin-nutrients shell-core nanoparticle usually apply acid/alkaline pH transition, which may cause the activity loss of the food nutrients or the formation of insoluble aggregates. In attempt to tackle these limitations, a simple one-step method was utilized to prepare the red bean seed ferritin (RBF)-epigallocatechin (EGC)-chitosan nanoparticle (REC) by thermal treatment at 55 °C. Results indicated that the apoRBF was partially uncoiled with a decrease of 5.3% of α-helix content induced by 55 °C treatment, and the EGC molecules could spontaneously permeate into the inner cavity of the ferritin with an encapsulation ratio of 11.8% (w/w). Meanwhile, the thermal treatment facilitated the chitosan attaching onto the outer surface of the ferritin by electrostatic interactions with a binding constant of 4.7 × 10 5  M −1 . Transmission electron microscope and dynamic light scattering results indicated that the REC was mono-dispersedly distributed, with a diameter of 12 nm and a hydrodynamic radius (R H ) of 7.3 nm. In addition, the chitosan decorating onto the apoRBF improved the EGC stability by weakening the degradation of apoRBF against digestive enzymes in simulated gastrointestinal tract. This work is a novel attempt to fabricate shell-core nanoparticle in the encapsulation and delivery of functional molecules based on the ferritin cage in a benign condition without extreme pH changes. [ABSTRACT FROM AUTHOR]

The objective of this study was to determine the effects of low-concentration acidic electrolyzed water (LcEW) combined with ultrasound (US) on fresh-sliced button mushrooms ( Agaricus bisporus), by evaluating the enzymatic browning, physio-biochemical changes, and microbial loads. The sliced button mushrooms were divided randomly into three groups (control, LcEW, and LcEW+US) and treated separately with tap water, LcEW, and LcEW+US for 3 min, and afterwards, they were stored at 5 °C for 8 days. The results indicated that LcEW delayed surface browning and maintained the flesh firmness of fresh-cut mushrooms compared with the control, and ultrasound enhanced these effects. Moreover, LcEW+US slowed down the electrolyte leakage (EL) rate and malondialdehyde (MDA) content, which were 5.29% and 0.5227 μmol/fresh weight less than those in control at day 8, respectively. The combined treatment of LcEW and US also significantly inhibited the activities of polyphenol oxidase (PPO) and peroxidase (POD) and controlled the counts of total bacteria (TBC) and yeast and mold counts (Y&M). Meanwhile, LcEW+US maintained a high level of total soluble protein and total phenolic contents, which were 1.49 and 1.24 times higher than those in control at the end of the storage time, respectively, and the combined treatment was more effective than LcEW treatment alone. These results demonstrated that the combination of LcEW and US could be an effective pretreatment technology in maintaining the product quality and prolonging the shelf life of fresh-sliced button mushrooms. [ABSTRACT FROM AUTHOR]

Ferritin naturally has a shell-like architecture with inner/outer surfaces, which can be applied as a nanovehicle of biologically active molecules. Herein, a CHAPS-involved scheme was arranged to fabricate the ferritin-agaro oligosaccharide-epigallocatechin gallate (EGCG) nanoparticle (FAE) partitioned by the ferritin shell. A concentration (10 mM) of CHAPS expanded the channel size of phytoferritin by remarkably improving the rate of iron release and facilitated the encapsulation of EGCG without disassembling the ferritin. The encapsulating ratio of EGCG reached (10.8 ± 0.13) %, about 17.2 EGCG per ferritin cage. Meanwhile, agaro oligosaccharide could attach on the ferritin outer surface with a stoichiometric number of 12.1 ± 0.31 (agaro oligosaccharide/ferritin) and a binding constant of (3.25 ± 0.23) × 105 M−1. The diameter of FAE was maintained at ∼12 nm, and the hydrodynamic radius (R H) was 7.61 nm, proving that the agaro oligosaccharide attachment and the encapsulation of EGCG retained the ferritin morphology. In addition, the CHAPS acted in alleviating the association effect of the ferritin when forming FAE. Moreover, the agaro oligosaccharide as the second layer attaching on the ferritin surface significantly improved the EGCG stability in FAE towards heating treatment and controlled the release of EGCG in a more sustained manner. This study highlights the role of CHAPS and fabricates a triple-layer nanoparticle in a simple way, which expands the fabrication method of oligosaccharide-protein-polyphenol polymers and is conducive to the stability of food bioactive molecules. [Display omitted] • CHAPS could induce the expansion of the size of the ferritin channels. • CHAPS enabled the formation of ferritin-AO-EGCG triple-layer nanoparticle (FAE). • CHAPS alleviated association effect of ferritin and promoted EGCG encapsulation. • AO attaching on the ferritin improved the thermal stability of EGCG. • AO attaching on the ferritin sustained the controlled release of EGCG. [ABSTRACT FROM AUTHOR]

A PG-tb1 hapten from the West Beijing strains of Mycobacterium tuberculosis cell wall has been efficiently synthesized and conjugated to CRM 197 in a simple way as linker-equipped carbohydrate by applying squaric acid chemistry for an original neoglycoprotein, creating a potent T-dependent conjugate vaccine. The intermediate monoester can be easily purified and the degree of incorporation can be monitored by MALDI-TOF mass spectrometry. After administered systemically in mice without any adjuvant, the conjugate induced high antigen-specific IgG levels in serum. Furthermore, following the third immunization, significant antibody titers frequently exceeding 0.8 million were observed in the sera of mice vaccinated with PG–CRM 197 conjugate which showed the potential for preparation of TB vaccine. [ABSTRACT FROM AUTHOR]

Rice bran albumin protein (RAP) is sensitive to thermal changes and tends to degrade when exposed to high-temperature processing. In this work, RAP-epigallocatechin-3-gallate (EGCG) complex (RAPE) was prepared and the thermal stability was evaluated. Fluorescence results showed that EGCG could interact with RAP with a binding number n of 0.0885:1 (EGCG:RAP, w/w) and a binding constant K of 1.02 (± 0.002) ×104/M, suggesting both hydrogen bonding and van der Waals forces played an important role. FTIR analysis demonstrated that EGCG could induce secondary structural changes in RAP above a ratio of 1.6:1 (EGCG:RAP, w/w). Interestingly, the secondary structure changes of RAPE at different temperatures (25, 50, 60, 70, and 80 °C) were inhibited compared with that for RAP, suggesting RAPE was more resistant and stable to the heat treatment. In addition, a dense porous structure of RAPE was achieved due to the EGCG binding after thermal treatment. Furthermore, the Tpeak temperature of RAPE increased significantly from 64.58 to 74.16 °C and the enthalpy also increased from 85.53 to 138.52 J/g with a mass ratio increasing from 0 to 3.2 (EGCG:RAP, w/w), demonstrating the thermal stability of RAPE. In addition, the valine, methionine, and lysine content in RAPE were significantly higher than RAP following 80 °C treatment for 20 min ( P < 0.05), exhibiting enhanced amino acid profiles, which might be due to EGCG-RAP interactions and microenvironment changes around relevant amino acids. These findings demonstrate that EGCG has the potential to improve the thermal stability of sensitive proteins and is beneficial for usage in the food industry. [ABSTRACT FROM AUTHOR]

Phycoerythrin (PE) is a kind of natural and nontoxic pigment protein with a distinctive phycobilin, and this pigment is easy to be destroyed in the process of food application, which makes its stability weak and application limited. In this work, PE was extracted by freeze-thaw method from Porphyra haitanensis , and the transglutaminase (10 U g−1 protein) was used to catalyze the glycosylation reaction between PE and oligochitosan with molar ratios of 1:1 to 4:1 (oligochitosan/PE) to obtain the oligochitosan-modified phycoerythrin complexes (OMPC). The glycosylation of oligochitosan to PE was proven by the polyacrylamide gel electrophoresis and was evidenced by the glucosamine and free amino analysis. When the molar ratio of oligochitosan to PE was 3:1, the glucosamine content of OMPC was the highest, which was 31.403 ± 0.004 mg g−1 protein. The OMPC samples were studied by infrared spectrum, fluorescence spectrum, and scanning electron microscopy. The results showed that the secondary structure and tertiary structure of glycosylated products changed, and a compact polymer appeared. In addition, compared with untreated PE, the surface hydrophobicity and emulsifying activity of OMPC decreased, while the solubility, emulsifying stability, thermal stability, photostability, and pH stability were significantly improved. This study reveals an innovative method to stabilize PE by a glycosylation approach, which will advance PE usage as a natural colorant in food applications. [Display omitted] • The oligochitosan-modified phycoerythrin complex (OMPC) is prepared by TGase. • Glycosylation alters the structure and physicochemical properties of phycoerythrin. • The OMPC shows high thermal, light, pH stabilities compared with phycoerythrin. • The study provides a scheme to stabilize phycoerythrin by a glycosylation approach. [ABSTRACT FROM AUTHOR]

Gray mold is a common postharvest disease caused by Botrytis cinerea that causes fruit decay and reduces fruit storage quality. In this study, the antifungal activity of antimicrobial peptide CB-M against B. cinerea and its mechanism of action, as well as the ability of CB-M to induce disease resistance in cherry tomato fruit, were investigated. CB-M had a strong inhibitory effect on spore survival and mycelial growth of B. cinerea , and these effects were enhanced with increased CB-M concentration. Moreover, significant leakages of cellular constituents and fluorescence microscopy assay confirmed that CB-M treatment could destroy the cell membrane integrity of B. cinerea. Scanning electron microscopy observations further demonstrated obvious distortion and shriveling of B. cinerea hyphae. Gel retardation and SDS-PAGE assay showed that CB-M could likely bind to cellular DNA and degrade/inhibit protein synthesis in B. cinerea. Furthermore, preincubation with CB-M before pathogen inoculation significantly decreased lesion diameter and incidence of gray mold caused by B. cinerea in tomato, cherry tomato, and grape fruit throughout whole storage time. Cherry tomato was used to explore the ability of CB-M to induce gray mold resistance, and the results showed that CB-M preincubation enhanced the activities of superoxide dismutase, peroxidase, and catalase, accelerated the accumulation of pathogenesis-related proteins, flavonoids, and total phenolics, and increased the activities of β-1,3-glucanase, chitinase, and phenylalanine ammonia-lyase during storage. These results indicated that CB-M is a good substitute for fungicides and has excellent prospects for controlling postharvest gray mold in horticultural crops. [Display omitted] • Antimicrobial peptide CB-M significantly inhibited Botrytis cinerea growth in vitro. • CB-M preincubation inhibited B. cinerea infection of three kinds of fruit. • CB-M peptide could disrupt the membrane integrity of B. cinerea. • CB-M peptide could likely interfere with cellular DNA and proteins of B. cinerea. • CB-M peptide could induce resistance against gray mold in cherry tomato fruit. [ABSTRACT FROM AUTHOR]

Brown blotch disease caused by Pseudomonas tolaasii infection is one of the major problems affecting the storage quality of postharvest button mushrooms (Agaricus bisporus). In this study, P. tolaasii treatment accelerated the accumulation of pathogen resistance-related substances/proteins, induced disease resistance-related enzyme activities, and promoted the increase of jasmonic acid (JA) during the whole storage. To gain full insight into the defense mechanisms of button mushrooms against P. tolaasii , a transcriptomics analysis of mushroom samples at 12 h was conducted. A total of 2861 differentially expressed genes (DEGs) were identified, among which there were 1557 up-regulated and 1304 down-regulated genes. Further bioinformatic analysis showed that P. tolaasii inoculation mainly activated shikimate pathway, phenylpropanoid metabolism, sulfur metabolism, methane metabolism, arginine and proline metabolism, cysteine and methionine metabolism, JA biosynthesis and signaling pathways, as well as oxidative phosphorylation pathways. Transcriptomics data combined with qPCR verification indicated that 10 DEGs including PIP1 , MET3 , AGX , PAL1 , GCL , LOX 1/3 , PR-like , MYB3R , UCR , and SDHB are the most potential genes involved in the early defense of A. bisporus against P. tolaasii. Additionally, taking the physiological and transcriptomics results together, the existence and important participation of JA biosynthesis and signaling pathways were demonstrated in the disease resistance of A. bisporus , although this organism probably possesses different catalyzing enzymes and transduction pathways with plants. In a word, our findings revealed the mechanism of the button mushroom's early defense response against pathogens, providing a reference for the development of rational approaches to control of mushroom diseases. • Defense mechanisms of Agaricus bisporus against Pseudomonas tolaasii were revealed. • Genes involved in the disease defense of A. bisporus were elucidated by RNA-Seq. • Differentially expressed genes (DEGs) were mainly enriched in 8 pathways. • Ten potential DEGs involved in the disease defense of A. bisporus were selected. • JA biosynthesis and signaling pathways were important for mushroom disease defense. [ABSTRACT FROM AUTHOR]

Postharvest browning is the primary cause of a decrease in the shelf life of the white button mushroom ( Agaricus bisporus). This study investigated the effect of postharvest brassinolide (BL) treatment on metabolism in relation to browning of the white button mushroom. Each harvested mushroom was dipped into one of three solutions containing 0, 1, or 3 μM BL for 5 min and stored in darkness at 4 °C for 16 days. Our results indicated that treatment with BL restrains browning development and reduces the total phenolic content and polyphenol oxidase activity. In addition, BL treatment maintains lower weight loss, electrolyte leakage, and malondialdehyde content and inhibits any increase in lipoxygenase activity compared with those of the control mushrooms. Furthermore, BL treatment significantly decreases the accumulation of reactive oxygen species (ROS) and induces the antioxidant enzyme system. Compared with 1 μM BL, treatment with 3 μM BL is more effective in reducing cap browning. The reduction of membrane oxidative damage and ROS levels induced by BL inhibits enzymatic browning reaction in the white button mushroom. These findings suggest that treatment with BL could have the potential of inhibiting browning and thus maintaining the mushroom's commercial value. [ABSTRACT FROM AUTHOR]

Influenza A virus (IAV) is characterized by eight single-stranded, negative sense RNA segments, which allows for gene reassortment among different IAV subtypes when they co-infect a single host cell simultaneously. Genetic reassortment is an important way to favor the evolution of influenza virus. Novel reassortant virus may pose a pandemic among humans. In history, three human pandemic influenza viruses were caused by genetic reassortment between avian, human and swine influenza viruses. Since 2009, pandemic (H1N1) 2009 (pdm/09 H1N1) influenza virus composed of two swine influenza virus genes highlighted the genetic reassortment again. Due to wide host species and high transmission of the pdm/09 H1N1 influenza virus, many different avian, human or swine influenza virus subtypes may reassert with it to generate novel reassortant viruses, which may result in a next pandemic among humans. So, it is necessary to understand the potential threat of current reassortant viruses between the pdm/09 H1N1 and other influenza viruses to public health. This study summarized the status of the reassortant viruses between the pdm/09 H1N1 and other influenza viruses of different species origins in natural and experimental conditions. The aim of this summarization is to facilitate us to further understand the potential threats of novel reassortant influenza viruses to public health and to make effective prevention and control strategies for these pathogens. [ABSTRACT FROM AUTHOR]

BACKGROUND To understand whether arginine catabolism might be involved in hot air ( HA)-induced chilling tolerance mechanism in tomato fruit, we investigated the effect of HA treatment on endogenous arginine catabolism in relation to chilling injury. RESULTS Tomato fruit were harvested at mature green stage and treated with HA at 38°C for 12 h and then stored at 2°C for 21 days. The effects of HA treatment on fruit chilling injury and gene expression levels or enzyme activity, and metabolites related to arginine catabolism were evaluated. HA treatment reduced the chilling injury symptoms of tomato fruit and enhanced the accumulation of endogenous polyamines, especially putrescine and proline. This accumulation is associated with the increased transcript levels of genes encoding arginase ( LeARG1 and LeARG2), arginine decarboxylase ( LeADC), ornithine decarboxylase ( LeODC) and ornithine aminotransferase ( LeOAT) at most sampling times. However, HA treatment had little effect on nitric oxide synthase activity and nitric oxide concentration. CONCLUSION These results revealed that the reduction in chilling injury by HA treatment may be due to the accumulation of putrescine and proline induced primarily by activating the catabolism of endogenous arginine. © 2013 Society of Chemical Industry [ABSTRACT FROM AUTHOR]

The commercial Hβ (25, 50), HY (11) and HZSM-5(50) were dealuminated by acid leaching and subsequent calcination to improve their hydrophobic nature for the removal of bisphenol A (BPA). The structure and properties of the raw zeolites and the modified ones (labelled as T-Hβ (25, 50), T-HY (11), T-HZSM-5(50)) have been investigated comparatively by XRD, BET, SEM, XRF and contact angle test (CA). The results indicated that HY (11) and T-HY (11) had poor adsorption capacity for hydrophobic BPA because of destroyed crystalline phase of T-HY (11) and hydrophilic nature of HY (11). HZSM-5(50) and T-HZSM-5(50) also had poor adsorption ability for BPA molecules because larger BPA molecules cannot enter smaller pores of HZSM-5(50) and T-HZSM-5(50). However, the T-Hβ (25, 50) zeolites exhibited significantly higher adsorption capacity for BPA because their larger pore size remained than molecule size of BPA and larger water contact angles and molar ratios of SiO 2 /Al 2 O 3 of T-Hβ (25, 50) than Hβ (25, 50), respectively. BPA removal mechanism study showed that hydrophobic interaction force between BPA and T-Hβ (25, 50) should be a main driving force. The adsorption process conformed to pseudo-second order model and the three-parameter Redlich-Peterson model. The adsorption rate of BPA over T-Hβ (50) (0.01050 ​g ​mg−1 ​min−1) was 2.29 times faster than that over Hβ (50) (0.004581 ​g ​mg−1 min−1), and the maximum adsorption capacity of BPA on T-Hβ (50) (117.62 ​mg ​g−1) was 3.5 times than that on Hβ (50) (33.78 ​mg ​g−1). The acid treatment-calcination method is feasible and appropriate for modification of Hβ in order to remove hydrophobic organic pollutants. Three kinds of commercial zeolites including Hβ (25,50), HY (11) and H-ZSM-5 (50) were modified by acid leaching and calcination method to obtain dealuminated zeolites (T-Hβ (25,50), T-HY (11), T-H-ZSM-5(50)), whose structures and adsorption mechanism for hydrophobic bisphenol A were investigated comparatively. [Display omitted] • Acid leaching-calcination method was feasible for dealumination of Hβ among three zeolites. • The SiO 2 /Al 2 O 3 molar ratio of Hβ was improved greatly. • The maximum adsorption capacity of BPA on T-Hβ (50) (117.62 ​mg ​g−1) was 3.5 times than that on Hβ (50). • The hydrophobic interaction force between BPA and T-Hβ (50) was responsible for the BPA removal. [ABSTRACT FROM AUTHOR]

Abstract: Treatment of tomato (Solanum lycopersicum L. cv. Messina) fruit with hot air (HA) at 38°C enhanced the transcript levels of LeARG1 and LeARG2, the two genes encoding arginase, and arginase activity. The strongest induction of LeARG1 and LeARG2 transcripts was observed after fruit treated with 38°C HA for 12h, which also effectively alleviated chilling injury (CI) of tomato fruit, manifested as decreased CI index, electrolyte leakage and malondialdehyde content during cold storage. To investigate the potential role of arginase in HA-induced chilling tolerance, fruit were treated with HA, or arginase inhibitor Nω-hydroxy-nor-l-arginine (nor-NOHA) combined with HA and then stored at 2°C for up to 28d. The results showed that HA-induced arginase activity was strongly inhibited by pretreatment with nor-NOHA and the reduction of CI by HA was nearly abolished by the arginase inhibitor. In addition, HA treatment increased activities of superoxide dismutase, catalase and ascorbate peroxidase, inhibited peroxidase activities, and promoted the accumulation of arginine, proline and putrescine. These effects were partially counteracted by nor-NOHA except that arginine and putrescine accumulation was unaffected. Our results indicate that arginase induction may be partly involved in HA-induced chilling tolerance in tomato fruit, possibly by a mechanism involving activation of antioxidant enzymes and an increase in proline levels. [Copyright &y& Elsevier]

Abstract: Freshly harvested tomato fruit were pretreated with 0.2mM arginine at −35kPa for 0.5min and then stored at 2°C for 28d to investigate the effect of exogenous arginine treatment on endogenous arginine catabolism in relation to chilling injury (CI). Arginine treatment reduced the CI index of fruit and enhanced accumulation of polyamines, especially putrescine, and proline, which resulted from the increased activities of the catabolic enzymes arginase, arginine decarboxylase, ornithine decarboxylase and ornithine δ-aminotransferase at most sampling times. Nitric oxide synthase activity was also increased by arginine treatment, which at least partly contributed to the increased nitric oxide concentration. These results revealed that the reduction in CI by exogenous arginine may be due to the accumulation of putrescine, proline and nitric oxide induced by activating the different pathways of endogenous arginine catabolism. [Copyright &y& Elsevier]

Abstract: The influence of methyl jasmonate (MeJA) on levels of gene transcripts, enzyme activities and metabolites related to arginine catabolism and chilling injury (CI) was studied in cherry tomato (Solanum lycopersicum L. cv. Messina) fruit stored at 2°C for 21 days. The CI index of fruit pretreated with 0.05mM MeJA vapor for 12h at 20°C was reduced compared with that of untreated fruit. The reduction was associated with up-regulated arginine catabolism. The mRNA levels and activities of arginase, arginine decarboxylase (ADC) and ornithine aminotransferase (OAT) in treated fruit were higher than in control fruit, while those of ornithine decarboxylase (ODC) increased transiently in response to MeJA treatment during the early days of cold storage. Free putrescine (Put) and proline accumulated in MeJA-treated fruit, while levels of other arginine-related amino acids were affected by MeJA. Spermidine (Spd) and spermine (Spm) contents remained unchanged in response to MeJA treatment over most of the storage time. The results indicate that MeJA becomes involved in coordinated catabolism of arginine, and helps to improve chilling tolerance in cherry tomato fruit. [Copyright &y& Elsevier]

• Enzymatic hydrolysis and glycosylation of soybean protein isolate (SPI) are studied. • Addition of 0.5% and 0.75% (w/v) SPI hydrolysates weakens gel properties of SPI. • Glycosylation reduces the adverse effect of hydrolysates on the formation of SPI gel. • Glycosylated hydrolysates-added gels showed a lower stiffness than SPI gel. Enzymatic hydrolysis and glycosylation were successively applied to modify soybean protein isolate (SPI) and rheological and textural properties of acid-induced SPI gel added with the obtained SPI hydrolysates and their glycosylated products were then investigated. The incorporation of SPI hydrolysates decreased the elastic modulus (G′) and hardness of SPI gel, which might be related to the random aggregation between SPI hydrolysates and native SPI molecules via hydrophobic interactions. In addition, as the molecular weight of SPI hydrolysates decreased, the reduction in G′ and hardness became more significant. Although glycosylation of SPI hydrolysates weakened the adverse effects of hydrolysates on the SPI gel formation to some extent, the glycosylated SPI hydrolysates were still unable to improve the gel quality compared with the control. However, results of this research may provide important information for understanding the influencing mechanism of SPI hydrolysates and their glycosylated products on the formation of SPI gel. [ABSTRACT FROM AUTHOR]

• Ferritin interacts with chlorogenic acid-Fe(III) complex via hydrogen bonds. • Chlorogenic acid promotes oxidative deposition and release iron ion from ferritin. • Chlorogenic acid shows a high efficiency in Fe(II) chelation and •OH capture. • Chlorogenic acid could reduce the ferritin polymerization induced by ion iron. Ferritin is an iron-containing protein and functions in the maintenance of iron balance in organisms. Currently the interaction among ferritin, ion iron, and food bioactive compounds is still unclear. In this study, the mechanism underlying the interaction of ferritin, ion iron, and chlorogenic acid was investigated, as well as the effect of chlorogenic acid on the physicochemical properties of ferritin. The results showed that chlorogenic acid could interact with Fe(III) to form chlorogenic acid-Fe(III) complexes, which then bonded with ferritin via hydrogen bonds in the ferritin–chlorogenic acid-Fe(III) complexes. The chlorogenic acid showed a high efficiency in Fe(II) chelation and hydroxyl radical (•OH) capture, and could promote iron oxidation and iron release induced by ferritin. Chlorogenic acid could also effectively reduce the polymerization extent of ferritin induced by Fe(III) and Fe(II). This study elucidates the interactions of multiple components in foodstuffs by using a protein-metal-polyphenol model. [ABSTRACT FROM AUTHOR]

• Methyl jasmonate (MJ) induced SlMYC2 expression and fruit resistance to B. cinerea. • MJ induced GLYCOALKALOID METABOLISM gene expressions and α-tomatine content. • MJ induced SPRs expression, total and special phenolic acids and flavonoid contents. • The silence of SlMYC2 counteracted the induced effects of MJ on tomato fruit. • SlMYC2 is involved in MJ-induced resistance to B. cinerea in tomato fruit. The mechanism of SlMYC2, involved in methyl jasmonate (MJ)-induced tomato fruit resistance to pathogens, was investigated. The data indicated that MJ treatment enhanced the accumulation of total phenolics and flavonoids, as well as individual phenolic acids and flavonoids, which might be caused by the increased phenylalanine ammonia-lyase and polyphenol oxidase activities, induced pathogenesis-related gene (PR) expression, β-1,3-glucanase and chitinase activities, as well as α-tomatine, by inducing GLYCOALKALOID METABOLISM gene expression. These effects, induced by MJ, partly contributed to tomato fruit resistance to Botrytis cinerea. Nevertheless, the induction effects of MJ were almost counteracted by silence of SlMYC2 , and the disease incidence and lesion diameter in MJ + SlMYC2 -silenced fruit were higher than those in MJ-treated fruit. These observations are the first evidence that SlMYC2 plays vital roles in MJ-induced fruit resistance to Botrytis cinerea, possibly by regulating defence enzyme activities, SlPRs expression, α-tomatine, special phenolic acids and flavonoid compounds. [ABSTRACT FROM AUTHOR]