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In this study, the impacts of transglutaminase (TGase)-induced glycosylation and limited enzymatic hydrolysis on the foaming property of soy protein isolates (SPI) and the possible underlying mechanisms were investigated. SPI were first glycosylated with oligochitosan by TGase to produce glycosylated samples (GSPI). GSPI were further hydrolyzed using Protamex with controlled degree of hydrolysis (DH of 1%, 2% and 4%). As compared to native SPI, the foaming stability of GSPI sample was increased from 24.3% ± 3.1% to 40.4% ± 7.6%, and the hydrolyzed GSPI showed enhanced foaming property. GSPI-1% DH showed the best foaming capacity and foam stability, increasing about 2.12 folds and 2.33 folds, respectively. Hydrodynamic-size of dominant distribution peak in GSPI and its hydrolysates (1% DH) were about 3090 and 531 nm, respectively, which were bigger than that of SPI (about 220 nm). The presence of oligochitosan in GSPI decreased surface hydrophobicity, and the subsequent hydrolysis generated an opposite effect. GSPI and its hydrolysates had more flexible tertiary conformations as revealed by intrinsic fluorescence study. Overall, high values of negative zeta potential and apparent viscosity of samples might be responsible for the improved foaming property. This study suggested that TGase-induced glycosylation and limited enzymatic hydrolysis are promising techniques for enhancing the foaming property of SPI, which would broaden the applications of SPI in food industry.

A novel fibrinolytic enzyme, ACase was isolated from fruiting bodies of a mushroom, Agrocybe aegerita. ACase was purified by using ammonium sulfate precipitation, gel filtration, ion exchange and hydrophobic chromatographies to 237.12 fold with a specific activity of 1716.77 U/mg. ACase was found to be a heterodimer with molecular mass of 31.4 and 21.2 kDa by SDS-PAGE and appeared as a single band on Native-PAGE and fibrin-zymogram. The N-terminal sequence of the two subunits of ACase was AIVTQTNAPWGL (subunit 1) and SNADGNGHGTHV (subunit 2). ACase had maximal activity at 47 °C and pH 7.6. It's activity was improved by Cu2+, Na+, Fe3+, Zn2+, Ba2+, K+ and Mn2+, but inhibited by Fe2+, Mg2+ and Ca2+. PMSF, SBTI, aprotinine and Lys inhibited the enzyme activity, which suggested that ACase was a serine protease. ACase could degrade all three chains (α, β and γ) of fibrinogen. Moreover, the enzyme acted as both, a plasmin-like fibrinolytic enzyme and a plasminogen activator. It could hydrolyze human thrombin slightly, which indicated that the ACase could inhibit the activity of thrombin and acted as an anticoagulant to prevent thrombosis. Based on these results, ACase might act as a therapeutic agent for treating thrombosis, or as a functional food. Further investigation of the enzyme is underway.

In this study, magnetic Fe3O4@SiO2@β-cyclodextrin copolymerized microparticles were synthesized and applied for the extraction of methyl parathion and fenthion in lettuce samples followed by HPLC-UV detection. The magnetic β-cyclodextrin copolymerized microparticles were prepared by dispersion polymerization with acryloyl β-cyclodextrin as the functional monomer and ethylene glycol dimethyacrylate as the crosslinker. The composite magnetic microparticles were characterized by Fourier transform infrared spectroscopy, X-ray diffraction, magnetic measurement, and thermogravimetric analysis, and used as the adsorbent of magnetic solid-phase extraction (MSPE) for methyl parathion and fenthion. The extraction conditions including sample pH and ionic strength, desorption solvent type and volume, and adsorption and desorption times were optimized. Under the optimal extraction conditions, an MSPE-HPLC-UV method was developed for the detection of methyl parathion and fenthion in lettuce. Wide linear ranges of 1.0-200 μg kg-1 (R2 = 0.9998) for methyl parathion and 1.5-200 μg kg-1 (R2 = 0.9978) for fenthion were obtained and the limits of detection were 0.3 μg kg-1 for methyl parathion and 0.5 μg kg-1 for fenthion in lettuce, respectively. The proposed method was applied for the determination of methyl parathion and fenthion in lettuce with satisfactory recoveries between 89.2-101.2%, and relative standard deviations were less than 9.1%. Thus, the MSPE-HPLC-UV method has high accuracy and sensitivity for the analysis of methyl parathion and fenthion in lettuce samples.

Objective Arteriosclerosis is an age-related disease and a leading cause of cardiovascular disease. In animal experiments, mesenchymal stem cells and its culture-conditioned medium have been shown to be promising tools for prevention or treatment of arteriosclerosis. On the basis of these evidences, we aimed to assess whether administration of autologous adipose-derived mesenchymal stem cells (Ad-MSC) is safe and effective for treatment of arteriosclerosis. Methods We retrospectively reviewed clinical records of patients with arteriosclerosis who had received autologous Ad-MSC administration at our clinic. Patients’ characteristics were recorded and data on lipid profile, intimal-media thickness (IMT), cardio-ankle vascular index (CAVI), and ankle-brachial index (ABI) before and after Ad-MSC administration were collected and compared. Results Treatment with Ad-MSC significantly improved HDL, LDL, and remnant-like particle (RLP) cholesterol levels. No adverse effect or toxicity was observed in relation to the treatment. Of the patients with abnormal HDL values before treatment, the vast majority showed improvement in the values. Overall, the measurements after treatment were significantly increased compared with those before treatment (p p Conclusions These findings suggest that Ad-MSC administration is safe and effective in patients developing arteriosclerosis, thereby providing an attractive tool for anti-aging application.

In mass casualty events involving radiation exposure, there is a substantial unmet need for identifying and developing an orally bioavailable agent that can be used to protect the hematopoietic stem cell pool and regenerate hematopoiesis after radiation injury. Dimethyl sulfoxide (DMSO), a free-radical scavenger, has shown therapeutic benefits in many preclinical and clinical studies. This study investigates the radioprotective effects of DMSO on oral administration. Single dose of oral DMSO administrated before irradiation conferred 100% survival of C57BL6/J mice receiving otherwise lethal as well as super-lethal radiation dose, with wide radioprotective time frame (from 15min to 4h). Oral DMSO not only protected radiation-induced acute hematopoietic stem and progenitor cell (HSPC) injury, but also ameliorated long-term BM suppression following irradiation in mice. Mechanistically, DMSO directly protected HSPC survival after irradiation in vitro and in vivo, whereas no radioprotective effect was seen in MLL-AF9-induced leukemia cells. Unexpectedly, DMSO treatment did not inhibit radiation-induced HSPC apoptosis, and the HSPC survival from Trp53-and PUMA-deficient mice after irradiation was also protected by DMSO. In conclusion, our findings demonstrate the radioprotective efficacy of oral DMSO. Given its oral efficacy and little toxicity, DMSO is an attractive candidate for human use in a wide variety of settings, including nuclear accidents and medical radiation.

In this study, porous sandwich structure Fe3 O4 nanoparticles coated by polyhedral oligomeric silsesquioxanes and β-cyclodextrin were prepared by surface polymerization and were used as the magnetic solid phase extraction adsorbent for the extraction and determination of carbaryl and carbofuran. The Fe3 O4 nanoparticles coated with polyhedral oligomeric silsesquioxanes and β-cyclodextrin were characterized by Fourier transform infrared spectroscopy, X-ray diffraction, thermogravimetric analysis, vibrating sample magnetometry, and scanning electron microscopy. After optimizing the extraction conditions, a method that combined magnetic solid phase extraction with high-performance liquid chromatography was developed for the determination of carbaryl and carbofuran in apple. The method exhibited a good linearity in the range of 2-400 μg/kg for carbaryl and carbofuran (R2 = 0.9995), respectively. The limits of detection were 0.5 μg/kg of carbaryl and 0.7 μg/kg for carbofuran in apple, respectively. Extraction recoveries ranged from 94.2 to 103.1% with the preconcentration factor of 300 and the relative standard deviations were less than 5.9%. These results indicated that the method combined magnetic solid phase extraction with high-performance liquid chromatography and was promising for the determination of carbaryl and carbofuran at trace amounts.

Alcoholic liver disease is one of the most prevalent chronic diseases that causes high morbidity and mortality worldwide. This study demonstrated the protective potential of Alcalase-black soybean-derived peptides (BSPs) against alcohol-induced liver injury in mice. BSPs were rich in oligopeptides (80%, w/w, 0.05). All treatments significantly (P

Over-application of nitrogen fertilizer in fields has had a negative impact on both environment and human health. Domesticated rice varieties with high nitrogen use efficiency (NUE) reduce fertilizer for sustainable agriculture. Here, we perform genome-wide association analysis of a diverse rice population displaying extreme nitrogen-related phenotypes over three successive years in the field, and identify an elite haplotype of nitrate transporter OsNPF6.1HapB that enhances nitrate uptake and confers high NUE by increasing yield under low nitrogen supply. OsNPF6.1HapB differs in both the protein and promoter element with natural variations, which are differentially trans-activated by OsNAC42, a NUE-related transcription factor. The rare natural allele OsNPF6.1HapB, derived from variation in wild rice and selected for enhancing both NUE and yield, has been lost in 90.3% of rice varieties due to the increased application of fertilizer. Our discovery highlights this NAC42-NPF6.1 signaling cascade as a strategy for high NUE and yield breeding in rice., Improving crop nitrogen use efficiency can facilitate sustainable production, however, the genetic mechanisms have not been fully revealed. Here, the authors discover the NAC42-NPF6.1 signaling cascade mainly derives from indica and wild rice and demonstrate the potential of using the allele for cultivar improvement.

Increasing use of TiO2 nanoparticles (NPs) leads to an accumulation in environment and a risk to human. In this work, an on-line monolithic capillary microextraction (CME)-inductively coupled plasma mass spectrometry (ICP-MS) method was developed for sensitive determination of TiO2 NPs in environmental water samples. With the presence of citric acid, TiO2 NPs can be selectively adsorbed on the poly(acrylamide)-vinylpyridine-methylene bis-(acrylamide) (poly(AA-VP-Bis)) monolithic column at pH 1, whereas Ti ions cannot be adsorbed. Factors affecting the extraction efficiency such as sample pH, concentration of citric acid and elution conditions were carefully investigated. Under the optimum conditions, a detection limit of 0.63 μg L−1 for TiO2 NPs and a sample throughput of 6 h−1 were achieved. The method can be applied to the determination of TiO2 NPs in the size range of 5–100 nm. The developed method was then applied to the analysis of TiO2 NPs in the East Lake water and Yangtze River water, and recoveries of 84–109% were obtained for spiked samples. Compared with other reported methods for the determination of metal oxide NPs, the developed on-line monolithic CME-ICP-MS has the merits of simple operation, high throughput and no need for digestion before ICP-MS detection.

To improve the electrochemical performance of CFx for lithium primary batteries, a ball milling treatment of CFx and urea with various mass ratios is carried out in this paper. It is shows that the weight ratio of urea/CFx significantly affects the electrochemical performance of the ball-milled CFx. Electrochemical tests show that the modified CFx material exhibits excellent electrochemical performance with much enhanced rate capacity, improved discharge platform, and lowered initial potential delay compared with the untreated CFx. In detail, when the weight ratio of urea/CFx is 5, the material delivers a discharge capacity of 550.6 mAh g−1 with a high power density of 10309 W kg−1 (at 5000 mA g−1 and 25 °C) and exhibits an excellent electrochemical stability at low temperature of 5 °C (power density up to 5922.5 W kg−1 at 3000 mA g−1). The outstanding electrochemical performance is mainly due to the synergistic effect of enlarged interlayer distance, decreased particle size, and increased surface area, which resulting in improved the electrochemical reaction activity, decreased reaction resistance, and facilitated lithium ions diffusion.

New glycopeptides were generated by proteolysis from corn gluten meal (CGM) followed by transglutaminase (TGase)-induced glycosylation with glucosamine (GlcN). The glycopeptides exhibited desirable antioxidant and intracellular ROS-scavenging properties. The amount of conjugated GlcN quantified by high-performance liquid chromatography (HPLC) was 23.0 g/kg protein. The formed glycopeptides contained both glycosylated and glycation types, as demonstrated by the electrospray ionization time-of-flight mass spectrometry (ESI-TOF MS/MS). The glycopeptides exhibited scavenging capabilities against free radical diphenylpicrylhydrazyl (DPPH) and hydroxyl radicals by reducing their power. The potential protection of glycopeptides against ethanol-induced injury in LO2 cells was assessed In Vitro based on methyl thiazole tetrazolium (MTT) testing and intracellular reactive oxygen species (ROS) scavenging capacity, respectively. Glycopeptide cytoprotection was expressed in a dose-dependent manner, with the glycopeptides exhibiting good solubility ranging from 74.8% to 83.2% throughout a pH range of 2&ndash, 10. Correspondingly, the glycopeptides showed good emulsifying activity (36.0 m2/g protein), emulsion stability (74.9%), and low surface hydrophobicity (16.3). These results indicate that glycosylation of CGM significantly improved its biological and functional properties. Glycopeptides from CGM could be used as potential antioxidants as well as comprising a functional food ingredient.

The intermolecular interactions and molecular packing form of fluorescent molecules have a huge impact on their optical properties, especially for AIE molecules. As a class of typical AIE molecules, tetraphenylethene (TPE) and its derivatives have prominent optical properties; nevertheless, separation of mixtures of E/Z isomers is a great challenge. Herein, a series of aromatic-substituted TPE derivatives were synthesized and used to separate mixtures of E/Z isomers by common column chromatography with high yields, as confirmed by single crystal analysis, mass spectrometry and NMR spectroscopy. The structure–property relationships of these molecules were systematically investigated by a combination of spectroscopic methods, theoretical calculations and single crystal data analysis. E/Z isomers exhibit many different fluorescent properties, such as AIE and mechanochromic behavior. Moreover, the position of N on the substituted pyridine ring also has an effect on the molecule stack pattern and the fluorescent properties. Collectively, our findings could not only improve the fundamental understanding of the cis/trans isomerization and photophysical properties of TPE derivatives but also provide a good strategy for designing different substituted groups that can produce various functions and have more potential applications.

Covalent organic frameworks (COFs) are a class of crystalline porous materials utilized in various potential applications. However, the development of hollow-structured COFs with defined morphology is important for their further applications, which is rare. Herein, COF with unique hollow shuttle morphology was prepared by a Schiff condensation reaction between 4-(4-aldehyde phenyl)ethylene (TPE) and tetra-(4-aminophenyl) porphyrin (TAP). A detailed mechanistic investigation reveals that an initial self-assembly followed by a similar inside-out Ostwald ripening process is responsible for the hollow capsule formation. The hollow microshuttle-shaped capsule COF is used for studying hemoglobin adsorption, which shows an uptake of 550.82 mg g-1 of hemoglobin. These studies could foreshadow new avenues for the development of porous materials with defined morphologies for the adsorption of biomolecules.

Here, a new 1D helical chain coordination polymer with enhanced chemical stability and fluorescence emission was prepared by introducing a benzimidazole molecule into Ag12 clusters. This coordination polymer demonstrated an increased fluorescence intensity with increasing polarity of alcohol solution, revealing its potential application in alcohol sensing.

Enzyme-mimicking nanomaterials (nanozymes) have been used to catalyze enzyme-like reactions for various applications. Despite these favorable properties, peroxidase-mimicking nanozymes suffer from the optimum reaction occurring in acidic solutions, which greatly limits their applications in biological systems. Herein, we demonstrate that copper Metal–Organic Polyhedra (Cu-MOP) nanorods exhibit high peroxidase-mimicking activity at a physiological pH value. Cu-MOP nanorods catalyze the generation of strong chemiluminescence signals in the presence of luminol/H2O2 and the oxidation of 2,2′-azinobis-(3-ethylbenzthiazoline-6-sulphonate acid) (ABTS) by H2O2 produces a green color reaction in a neutral pH solution. The Cu-MOP nanorod driven generation of color reactions is applied to develop a H2O2 sensor, and furthermore is implemented to develop a glucose detection platform.

To develop a convenient method for sensitive and selective determination of Ce3+ in aqueous phase with complicated matrices, a carbon paste electrode (CPE) modified with ion imprinted polymers (IIPs) were fabricated. The polymers were prepared by precipitation polymerization using Ce3+ as template, allyl phenoxyacetate (APA) as monomer, ethylene glycol dimethacrylate (EGDMA) as crosslinker and azobisisobutyronitrile (AIBN) as initiator under the molar ratio of Ce3+, APA and EGDMA as 1:4:40, respectively. Ce3+ was detected directly by differential pulse adsorptive stripping voltammetry (DPASV) and its oxidation peak appears at about 0.93 V. All parameters affecting the sensor's response are optimized and a calibration curve is plotted at a linear range of 1.0 × 10−6–1.0 × 10−5 mol/L and 1.0 × 10−5–2.0 × 10−4 mol/L with the detection limit of 1.5 × 10−7 mol/L. All other rare earth ions have no interference with the determination of Ce3+ even at a concentration 500 times higher than that of Ce3+. This sensor was successfully applied to determination of Ce3+ in two catalyst sample solutions with RSD≤3.3% (n = 5) and recoveries in the range of 99.2%–106.5% at our optimal conditions.

Zein and its derived peptides have been used as nanocarriers for bioactive components. Lutein, as well as other xanthophylls, are characterized by blue light filtering and anti-oxidant properties. However, lutein is unstable and has low water solubility, poor absorption, and low bioavailability. In order to protect lutein from oxidative degradation, and to enhance its solubility and dispersibility, stability and bioactivity, lutein-loaded zein nanoparticles (LLZ-NP) and zein-derived peptide nanoparticles (LLZ-PEP-NP) were prepared by the solvent diffusion method. Compared to LLZ-NP, LLZ-PEP-NP possessed good physicochemical properties, including particle size, polydispersity index, zeta potential, entrapment efficiency and in vitro stability. Specifically, transmission electron microscopy (TEM) images showed that LLZ-PEP-NP had a spherical form with a nanometric size and lutein was efficiently loaded into zein-derived peptides through self-assembly. Dynamic light scattering (DLS) results demonstrated that LLZ-PEP-NP had a narrow size distribution in the range of 200-300 nm and a decreased zeta potential compared to that of LLZ-NP. The lutein entrapment efficiency (EE%) of LLZ-NP and LLZ-PEP-NP was more than 85%, while LUT-PEP-NP showed higher lutein entrapment efficiency because of the better capacity of peptides bound with lutein. Nanoencapsulation of lutein into LLZ-PEP-NP resulted in a significantly higher solubility compared to nanoencapsulation of lutein into LLZ-NP and free lutein. The stabilities of lutein in zein-derived peptide nanoparticles in simulated gastric fluid (SGF) and simulated intestinal fluid (SIF) were improved. These results suggest that zein-derived peptides have the potential to be used as nanocarriers to enhance the solubility and stability of lutein, which can further improve its bioavailability.

The focus of the present work was to investigate the glycosylation of zein, partial properties of the glycosylated zein (GZ) and its retarding effect on lipid oxidation of ground pork. Zein was glycosylated with chitosan (MW 1500Da) by microbial transglutaminase, the reaction was verified by FT-IR. Under the optimized conditions, 97.48mg of glucosamine was covalently conjugated to 1g of zein, determined by HPLC. The solubility and the surface hydrophobicity of GZ were significantly improved. In vitro studies of GZ showed a dose-dependent scavenging activity against free radicals of DPPH, superoxide and hydroxyl radical, and the EC50 value for DPPH radical was 1.99μg TE/mg protein. In addition, reducing power and Fe2+-chelating capacity of it were 16.60 and 12.96μg TE/mg protein, respectively. GZ resulted in low levels of thiobarbituric acid-reactive substances and peroxide value of ground pork. These results suggest that GZ is a potential natural antioxidant.

Neoalbaconol, derived from Albatrellus confluens, shows anti-cancer activities in the previously study, but its role in angiogenesis is unknown. Here, we determined whether neoalbaconol could attenuate angiogenesis and how does it occur. Data demonstrated that neoalbaconol could inhibit the proliferation of breast cancer cells and induce apoptosis. Also, neoalbaconol suppressed vascular endothelial growth factor (VEGF)-induced human umbilical vascular endothelial cells (HUVECs) proliferation, migration, invasion, and capillary-like tube formation in vitro and reduced tumor angiogenesis in vivo. VEGF receptor activation and the downstream signal transduction cascades activation were inhibited by neoalbaconol. Additionally, neoalbaconol blocked EGFR-mediated VEGF production. EGFR overexpression reversed the neoalbaconol-induced VEGF reduction, confirming the importance of the EGFR inhibition in anti-angiogenesis of neoalbaconol. Furthermore, neoalbaconol inhibited tumor growth and tumor angiogenesis in a breast cancer xenograft model in vivo. Taken together, these results indicate that neoalbaconol could inhibit tumor angiogenesis and growth through direct suppression effects on vascular endothelial cells and reduction of proangiogenic factors in cancer cells.

New glycosylated zein peptides (GZP) were produced by transglutaminase-induced d -glucosamine conjugation onto zein peptides. GZP’s antagonistic effects on alcohol-induced liver injury in rats were evaluated. Compared with the alcohol model group, GZP (250 mg/kg·bw) remarkably increased alcohol dehydrogenase, acetaldehyde dehydrogenase, endogenous antioxidant enzymes activities, and GSH levels in liver, decreased serum triacylglycerol, tumor necrosis factor-α, liver malonaldehyde, reactive oxygen species, and lipopolysaccharide (LPS) levels, and significantly reversed pathological changes in liver tissues. These results indicate that low-dose GZP administration can alleviate alcohol-induced liver injury by accelerating alcohol metabolism, reversing hepatic redox status, and attenuating LPS-mediated inflammation responses. GZP is a potential alcohol metabolism promoter and liver-protective agent.

Wounds infected by bacteria are dangerous for human beings. However, along with the emergence of new strains and strong bacterial resistance, traditional antibiotics are unable to meet the medical needs for treating bacterial infections. Thus, new antibacterial substances with superior antimicrobial properties are urgently needed. Herein, a hydrogel containing poly acrylic acid (PAA), glycerol and Cu-MOP (named PAA-Cu-MOP hydrogel) is obtained by a facile mixing and ultrasonic procedure for wound healing treatment. This PAA-Cu-MOP hydrogel with high biocompatibility exhibits excellent wound healing behavior and is even better than the one of recombinant human epidermal growth factor. Tissue experiment results reveal that the PAA-Cu-MOP hydrogel accelerates the wound healing process by promoting angiogenesis, stimulating cell proliferation, and up-regulating cell factors.

This study compared two immobilization matrices like calcium-alginate and chitosan for immobilization of α-galactosidase and evaluated their potential for the removal of non-digestible raffinose family oligosaccharides from soy milk which cause abdominal discomfort. The pH optima of the free and immobilized enzymes were found to be similar at pH 4.0. The chitosan-immobilized α-galactosidase displayed higher optimal temperature (60°C) compared to alginate-immobilized enzyme (45°C) and free enzyme (50°C). The chitosan-immobilized and alginate-immobilized α-galactosidases displayed 93.7% and 97.6% hydrolysis of raffinose family oligosaccharides, respectively, while the free enzyme hydrolyzed only 30.3% oligosaccharides present in soy milk in 4 hr. Remarkably, both the immobilized enzymes showed complete removal of raffinose family oligosaccharides in 8 hr. Moreover, reusability studies indicate that even after five cycles of reuse, the chitosan and alginate-immobilized enzymes displayed 99% and 60% hydrolysis, respectively. PRACTICAL APPLICATIONS: In this study, we have used two inexpensive and non-toxic matrices for immobilizing α-galactosidase. We report that entrapment of α-galactosidase with chitosan significantly improved the optimal temperature of α-galactosidase, which is advantageous in food industry. The hydrolysis of raffinose family oligosaccharides in soy milk was also greatly enhanced after immobilization with chitosan and alginate. Thus, the results described in this study have relevance for development of safe, cost-effective and efficient method for removal of non-digestible soy oligosaccharides in food industry.

Lead halide perovskites have attracted much attention following their successful use in photovoltaic devices with impressive power-conversion efficiencies. Owing to perovskite quantum dots’ ionic nature, the surface ligands are easy to be overdamaged in polar solvents. Thus, there have been some difficulties in protecting the surface ligands of the quantum dots during purification processes, especially in solvent reprecipitation techniques. Here, we used mixtures of ethyl acetate and methyl acetate during the purification process to precipitate perovskite quantum dots that showed scarcely any damage to their surface ligands; furthermore, these purified CsPbBr3 quantum dots displayed high performances in devices. Quantum dot films were prepared via spin-coating from solution for use in solar cells with a simple structure (indium tin oxide/ZnO/quantum dots/Au), which displayed power-conversion efficiencies of up to 2.43%. Multiple purification cycles of this purification process allowed us to obtain near-perfectly modified perovskite colloidal quantum dots, ideal for application in optoelectronic devices.

Objective This study was to establish a rapid quantitative method for determination of six characteristic flavonoids, including licochalcone A (1), liquiritigenin (2), glabridin (3), isoliquiritigenin (4), liquiritoside (5), and isoliquiritoside (6) in licorice by a ultra-performance convergence chromatography (UPC2) apparatus equipped with a photodiode-array detector (PDA). Methods: The flavonoids studied were separated on an ACQUITY UPC2 TM Torus 2-PIC column (2.1 × 100 mm, 1.7 μm) using gradient elution (85:15–70:30) with a mobile phase consisting of CO2 and methanol: formic acid (99.8:0.2, v/v), back pressure of 2,000 psi, flow rate of 0.8 mL/min, and detection at 254 nm. This method was further applied for the analysis of the flavonoids present in 10 batches of licorice roots samples. Results: Good linearity (R2 = 0.9990–0.9998) was achieved and limits of detection (LOD) and quantification (LOQ) ranging from 0.12 to 0.49 µg/mL and 0.46 to 1.61 µg/mL, respectively. The relative standard deviations (RSD) for repeatability and reproducibility were 2.30–2.80% and 2.30–2.98%, respectively. The flavonoids distributed differently in Glycyrrhiza uralensis , Glycyrrhiza glabra, and Glycyrrhiza inflate . Conclusion: The established rapid quantitative analysis method was environment friendly and suitable to the quality control of species licorice.

Monoliths composed of poly(1-vinylimidazole-ethylene glycol dimethacrylate), referred to as poly(VI-EGDMA), were modified with imidazole groups and used in capillary microextraction (CME) of trace levels of Co(II), Ni(II) and Cd(II) ions from human urine samples. The effects of sample pH, sample flow rate, sample volume, elution conditions and potentially interfering ions were investigated. Under the optimized conditions, the limits of detection (3σ) are 0.6 ng L−1 for Co(II), 6.4 ng L−1 for Ni(II) and 0.7 ng L−1 for Cd(II), with the relative standard deviations of 1.8 (Co), 4.2 (Ni) and 2.2% (Cd). A Certified Reference Material (ZK018–2, lyophilized human urine) was analyzed to validate the method, and the values found were in good agreement with the certified ones. The method was successfully applied to the analysis of trace Co, Ni and Cd in human urine samples, and the recoveries for spiked samples were in the range from 89% to 105%. The one-step preparation of monolithic material in our perception is an attractive feature for this material which also excels by good extraction performance in that it possesses abundant adsorption sites, good stability and a long lifetime.

A fibrinolytic enzyme was produced by the medicinal mushroom, Cordyceps militaris using submerged fermentation. The enzyme was purified from culture supernatant by hydrophobic interaction, ion exchange and gel filtration chromatographies. It was purified by 36 fold, with a specific activity of 1,467.4 U/mg protein and the final yield was 5.8%. The molecular weight of the enzyme as determined by SDS-PAGE and gel filtration was 28 kDa and 24.5 kDa, respectively, and its isoelectric point (pI) was 9.0 ± 0.2. It was found to be a glycoprotein with carbohydrate content of 1.67% (w/v). The enzyme was optimally active at 37 °C and pH 7.2. The enzyme activity was strongly inhibited by soybean trypsin inhibitor (SBTI) and aprotinin which indicated it to be a serine protease, while other inhibitors like N -α-tosyl- l -phenylalanine chloromethyl ketone (TPCK), phenyl methane sulfonyl fluoride (PMSF), pepstatin and metal chelator EDTA did not inhibit its activity. Amino acid sequences of the purified enzyme were determined partially by Q-TOF2 and they were IEDFPYQVDLR; ANCGGTVISEK; YVLTAGHCAEGYTGLNIR; TNYASVTPITADMICAGFPEGK; KDSCSGDSGGPLVTGGK; VVGIVSFGTGCAR; ANKPGVYSSVASAEIR. Sequences of the seven peptides completely matched with those of a trypsin-like serine protease from Cordyceps militaris CM01 (accession no. EGX95217.1 ). The purified enzyme degraded α chains of fibrinogen first and then β and γ chains and also activated plasminogen into plasmin. It can act as an anticoagulant and prevent clot formation by degrading fibrinogen. Based on these studies, the purified enzyme has great potential to be developed as a natural agent for prevention and treatment of thrombolytic diseases.

Stereoisomers play an irreplaceable prominent role in life sciences. In molecular engineering, the isomers have been continuously designed and synthesized, and their interrelationships among structure-property-function have also been explored. However, the difficulties in purification and structural confirmation of tetraphenylethene (TPE) derivatives' stereoisomers hinder their structural diversity and scope of functions. Meanwhile, there were few researches on the macroscopic optical differences about TPE derivatives isomers. Herein, isoniazid-substituted TPE derivatives stereoisomers have been synthesized, as confirmed by single crystal data, mass spectrometry and NMR spectroscopy. The different photophysical properties were caused by the introduction of functional group isoniazid on the periphery of TPE. These isomers possessed dramatic differences in fluorescent properties, and exhibited diverse changes in response to stimuli. They also have distinct aggregated self-assembly morphologies because of different intermolecular hydrogen bonding, and they can be used as efficient fluorescent probes for detecting copper. Based on the coordination-driven sensing system, the morphologies of isomers aggregates changed significantly after interaction with copper, and the stoichiometry between them is 2:1. The theoretical calculation demonstrated that they have obvious intramolecular charge transfer behavior. Our research provided a good strategy for designing different substituted groups that can produce various functions and have more potential applications.

In this study, a fungal and two yeast β-galactosidases were immobilized using alginate and chitosan. The biochemical parameters and lactose hydrolysis abilities of immobilized enzymes were analyzed. The pH optima of immobilized fungal β-galactosidases shifted to more acidic pH compared to free enzyme. Remarkably, the optimal temperature of chitosan-entrapped yeast enzyme, Maxilact, increased to 60 °C, which is significantly higher than that of the free Maxilact (40 °C) and other immobilized forms. Chitosan-immobilized A. oryzae β-galactosidase showed improved lactose hydrolysis (95.7%) from milk, compared to the free enzyme (82.7%) in 12 h. Chitosan-immobilized Maxilact was the most efficient in lactose removal from milk (100% lactose hydrolysis in 2 h). The immobilized lactases displayed excellent reusability, and chitosan-immobilized Maxilact hydrolyzed > 95% lactose in milk after five reuses. Compared to free enzymes, the immobilized enzymes are more suitable for cost-effective industrial production of low-lactose milk due to improved thermal activity, lactose hydrolysis efficiencies, and reusability.

The detection of Ag+ in the environment is very important to determine the level of pollution from silver complexes, which have caused various human health problems. Herein, an aggregation-induced emission (AIE) chromophore (tetraphenylethane, TPE) attached to a benzimidazole group (tetra-benzimidazole, TBI–TPE) is synthesized and utilized to detect Ag+ in the environment. The strong chelating effect between the benzimidazole group and Ag+ leads to the formation of aggregates, and strong yellow fluorescence signals were observed after adding Ag+ into a TBI–TPE solution. The stoichiometry of the complex of TBI–TPE and Ag+ was established to be 1 : 2 using photochemical and mass spectra measurements. The detection limit of the Ag+ assay is 90 nM with a linear range from 100 nM to 6 μM. This study provides a facile method to determine Ag+ in real environmental samples with satisfactory results.

Corn gluten meal (CGM) is a major by-product of corn wet milling. Pretreatments of CGM by Na2CO3, starch removal, and cooking reduced the total starch and fat by 93% and 78%, respectively. Higher antioxidant hydrolysate was prepared by using Alcalase, Protamex and Flavourzyme at a substrate concentration of 13.5% (w/w). The degree of hydrolysis reached 29.49% and 27.11%. The peptides in hydrolysate were in the range of 1200–250 Da. It increased the activities of superoxide dismutase, glutathione peroxidase, and reduced MDA equivalents of mice at a dose of 300 mg/kg. Therefore, corn gluten can be developed into an antioxidant supplement.

In the present study, non-waxy corn starch was processed by different freeze-thawing temperatures and cycles. The effects of freeze-thawing treatment on the surface structure, granules particle size, Maltese crosses, crystalline, and thermal properties of non-waxy corn starch were investigated. The number of pores on the surface of starch granules increased with freeze-thawing cycles. The granule size, crystalline intensity and degree, gelatinization temperatures, and enthalpy values of corn starch decreased with freeze-thawing cycles increased. The Maltese crosses indicated that loss of Maltese cross increased when freeze-thawing cycles increased, but decreased with increase in temperature. Moreover, clear cracks and big pores were observed on the surface of starch granules, and smaller granule size and lower thermal parameters were obtained in the distorted corn granules caused by the changes in crystalline structure under appropriate treatment (−20°C freezing and 25°C thawing, 20 cycles). Freeze-thawing treatment significantly increased the porosity of corn starch, which indicated that it can improve adsorptive capacity of starches. Therefore, freeze-thawing method is potentially very useful to produce porous starch as carrier or absorbent for food and medicine. These findings could have important applications in starch modification industry.

The physicochemical and functional properties, such as surface hydrophobicity, disulphide bond content, thermal properties, molecular weight distribution, antioxidant properties, of corn glutelin hydrolysates catalysed by Protamex at different hydrolysis times were evaluated. The hydrolysis influenced the properties of corn glutelin significantly, and not only decreased its molecular weight and disulphide bond content, but also eventually transformed its insoluble native aggregates to soluble aggregates during the hydrolysis process. Corn glutelin hydrolysates were found to have a higher solubility, which was associated with their relatively higher foaming and emulsifying properties compared to the original glutelin. Corn glutelin and its hydrolysates maintained a high thermal stability. In addition, the hydrolysates exhibited excellent antioxidant properties measured through in vitro assays, namely DPPH and OH radical scavenging activity, Fe2+-chelating capacity and reducing power; the values were 58.86%, 82.64%, 29.92% and 0.236% at 2.0 mg/mL, respectively.

Using cholesterol, stigmasterol and sitosterol as starting materials, a series of 7-subsitituted-ster-3-yl 2-methoxybenzoate analogs were prepared through reacting with 2-methoxybenzoyl chloride and introducing some function groups, such as carbonyl, hydroxyl and various thiosemicarbazones, at 7-position of steroidal nucleus. The structures of these new compounds were characterized by IR, NMR and HRMS. Their antiproliferative activities were evaluated by using several types of cancer cells. Interestingly, the compounds displayed potent antiproliferative activity against CNE-2 (nasopharyngeal carcinoma cell lines), BEL-7402 (human liver cancer cell lines) and HepG2 (human liver cancer cell lines), suggesting that they have potential to be drug candidates for cancer treatment.

A novel fibrinolytic enzyme from Cordyceps militaris was produced by submerged culture fermentation, purified, and biochemically characterized. The enzyme was purified to homogeneity, with an overall yield of 4.0% and a specific activity of 1682 U/mg. The molecular weight and pI of the enzyme were 32 kDa and 9.3 ± 0.2, respectively. The optimal pH and temperature of the enzyme were 7.4 and 37 °C, respectively. The enzyme activity was inhibited by Fe(2+), phenylmethane sulfonyl fluoride (PMSF), aprotinin, and pepstatin but not by N-tosyl-L-phenylalanine chloromethyl ketone (TPCK) and ethylenediamine tetracetic acid (EDTA). Three internal peptides of the enzyme, APQALTVAAVGATWAR, EKNVGSTVNLLSYDGNK, and TDATSVLLDGYNVSAVNDLVAK, were obtained. The enzyme could hydrolyze fibrin(ogen) directly and cleave the α-chains more efficiently than β- and γ-chains, suggesting that it is a plasmin like protein. It degraded thrombin, which indicated that it can act as an anticoagulant and prevent thrombosis. Intravascular thrombosis is one of the major reasons of cardiovascular diseases. On the basis of these results, the purified enzyme can be developed as a natural agent for oral fibrinolytic therapy or prevention of thrombosis.

In this study, the hydrophilic polymer monolithic capillary (poly(acrylamide-vinylpyridine-methylene bis(acrylamide)), poly(AA-VP-Bis)) was prepared for the separation and enrichment of carboxyl group-containing gold nanoparticles (Au NPs) from environmental waters followed by online ICPMS determination. The extraction mechanism of the prepared poly(AA-VP-Bis) monolithic capillary for Au NPs is based on the static electrical and hydrogen bond interactions between the carboxyl group on the surface of Au NPs and pyridine/amide groups on the surface of the monolith. Under the optimal conditions, a detection limit of 24.2 fmol L(-1) and a sample throughput of 6 h(-1) were achieved for 3 nm citrate stabilized Au NPs, and the original morphology of the Au NPs could be maintained during the extraction process. The developed method was successfully applied for the analysis of carboxyl group-containing Au NPs in environmental water samples, such as tap water, the Yangtze River water, and the East Lake water, with recoveries in the range of 77-103%. Compared with the reported approaches for analysis of Au NPs, this method is an online strategy for carboxyl group-containing Au NPs determination and has the merits of low detection limit, small sample consumption, fast extraction/desorption kinetics, wide linear range, high selectivity, and high throughput.

Kinetic inhibitor is an inhibitor of many studies in the field of natural gas hydrate inhibitor in recent years. In view of the inhibition of hydrate effect is obvious, high cost, so this paper carried out several inhibitors to inhibit the formation of gas hydrate, in order to meet the need of gas hydrate inhibition, but also take the economic factor into account. It was found that the synergistic effect of PVP and ethylene glycol two ether, ethylene glycol two ether and ethylene glycol phenyl ether in the inhibition of gas hydrate, and the synergistic effect of ethylene glycol phenyl ether was the most significant.

A HDBB@ZIF-8 fluorescent probe has been developed by encapsulating the aggregation-induced emission (AIE) molecule 4,4’-(hydrazine-1,2-diylidenebis(methanylylidene)) bis(3-hydroxybenzoic acid) (HDBB) into the nanochannels of zeolitic imidazolate frameworks-8 (ZIF-8) for distinguishing small alcohol solvent molecules. The crystal structure and morphology of ZIF-8 are well maintained after the encapsulation of HDBB molecules. Encapsulation of HDBB into the confined nanospace of ZIF-8 not only triggered new green fluorescent emission but also endowed them with unique carbon chain length-dependent fluorescence intensity for alcohols, which has not been observed in pure HDBB and ZIF-8. This property could be attributed to the alcohol–water sorption selectivity of host ZIF-8. Moreover, a linear relationship is obtained between the fluorescent intensity of these composites and the concentrations of ethanol with a wide linear range, which could be employed as a chemosensor to detect the content of ethanol in the real wine sample.

The study of molecule-DNA interaction is very important for designing an improved therapeutic agent. In previous studies, we synthesized some B-norcholesteryl benzimidazole compounds, and the tests on cancer cells showed that these compounds had good in vitro anti-cancer activities. In order to further investigate mechanism of their actions, three different B-norcholesteryl benzimidazole compounds were selected and interaction of these compounds with the calf thymus DNA (ct-DNA) was monitored by using various methods including UV–Vis and fluorescence spectroscopic techniques, viscosity measurement, and circular dichroism (CD). The results proved a hypochromic effect accompanied with a slight red-shift due to the interaction of the molecules with ct-DNA. According to the UV-Vis and fluorescence spectra, the mentioned compounds were bound to DNA, preferentially through partial intercalation into the DNA helix. Moreover, the ethidium bromide (EB) and Hoechst 33258 competitive binding experiments were also used to confirm the interaction mode of the compounds with ct-DNA. In the Hoechst 33258 displacement experiment, no significant change in the fluorescence intensity was observed. Additional assays such as iodide quenching, viscosity, and CD spectroscopy further confirmed that intercalation should be the major binding mode of the selected compounds with DNA. The cytotoxicity of these three compounds was also evaluated by MTT method, and the results confirmed that binding ability of these compounds to DNA was consistent with their cytotoxicity behavior. The experimental results indicated a higher binding affinity for compound 3 compared to the other compounds. This research provided a better understanding on the molecular mechanism of the interaction between B-norcholesteryl benzimidazole compounds and tumor cells, and offered a beneficial perspective to the designation of novel B-norsteroidal anticancer compounds.

In the present study, corn protein hydrolysate (CPH) with antioxidant activity was obtained by enzymatic hydrolysis. Corn gluten meal (CGM) was hydrolyzed using two proteases (Alcalase and Protamex) to produce the antioxidant peptide. Extrusion and starch removal of corn protein were used as pretreatment procedures before proteolysis. Hydrolysis by Alcalase has more remarkable digesting efficiency on corn protein than that by Protamex. Therefore, the hydrolysate catalyzed by Alcalase was fractionated by ultrafiltration, and peptide with the highest antioxidant activity was purified from

In this study, the structure and selected properties of zeins extracted from corn gluten meal (CGM) pretreated by extrusion and removal of starch were investigated. The structure and properties of the zeins from pretreated CGM changed significantly. Pretreatments can decrease the extraction yields of zeins and change the granule shape and size of zein aggregates. The studies indicated that extrusion and removal of starch can significantly decrease the thermal enthalpy (ΔH1 and ΔH2) of zein from 1.94 ± 0.20 to 0.19 ± 0.10 and from 107.20 ± 0.80 to 78.62 ± 2.30 and J/g, respectively. The SDS-PAGE results confirmed that the molecular weight of zeins from CGM was 24,000 and 27,000, and the molecular weight of zeins did not change with the pretreatment. On the other hand, the circular dichroism spectroscopy results showed that the processing of extrusion and removal of starch can change the secondary structure content of β-sheets and β-turns; these results indicated that extrusion and removal of starc...

A study was conducted to evaluate the effects of inoculation with a combination of Bacillus licheniformis (1.0813), Yeast (ACCC20060) and Lactobacillus (ACCC10637) on the nutrient characteristics and sensory properties of rapeseed meal (RSM) and to investigate the bioavailability by in vivo and in vitro experiments. The results showed that the soluble protein content, lactic acid content and total amino acid content increased significantly (P

A fibrinolytic enzyme was produced by an edible mushroom of Pleurotus ostreatus using submerged culture fermentation. The enzyme was purified from the culture supernatant by applying a combination of freeze-thaw treatment, ammonium sulfate precipitation, hydrophobic interaction, and gel filtration chromatographies. The enzyme was purified by a 147-fold, with a yield of 7.54%. The molecular masses of the enzyme an determined by gel filtration and SDSPAGE were 13.6 and 18.2 kDa, respectively. The isoelectric point of the enzyme was 8.52. It hydrolyzed fibrinogen by cleaving the α and β chains of fibrinogen followed by the γ chains, and also activated plasminogen into plasmin. The enzyme was optimally active at 45°C and pH 7.4. The enzyme activity was completely inhibited by EDTA, whereas protease inhibitors of TPCK, SBTI, PMSF, aprotinin and pepstatin showed no inhibition on its activity. The partial amino acid sequences of the enzyme as determined by Q-TOF2 were ATFVGCSATR, GGTLIHESSHFTR, and YTTWFGTFVTSR. These sequences showed a high degree of homology with those of metallo-endopeptidases from P. ostreatus and Armillaria mellea. The purified enzyme can also be applied as a natural agent for oral fibrinolytic therapy or prevention of thrombosis.

Cadmium sulfide (CdS) nanowires were synthesized on Cd foil via a simple solvothermal reaction at 180 °C using thiosemicarbazide as the sulfide source and ethylenediamine as the solvent. The CdS nanowires are hexagonal-phase single crystals with an average diameter of 50 nm and length of several microns. The as-prepared CdS nanowires show an absorption peak of around 483 nm in the absorption spectrum. The CdS nanowires exhibit bright photoluminescence (PL) with two distinct emission bands at 503 nm and 697 nm, which shows that the as-prepared CdS nanowires are high-quality nanocrystals.

Amylopectin retrogradation is a serious problem in starch-based ready meals. In the current research, rice amylopectin was frozen by low temperature (−20, −30, and −60°C) and ultra-low temperature (−100°C), and then stored at 4°C for 21 days or at −18°C for up to 5 months to evaluate the retrogradation properties. Amylopectin retrogradation enthalpy of rice was determined by a differential scanning calorimetry. The results showed that low temperature and ultra-low temperature freezing can effectively retard amylopectin retrogradation during the freezing process and during frozen storage (−18°C) for at least 5 months. However, rice amylopectin still retrograded after the freezing process during chill storage at 4°C. The methods of low and ultra-low temperature freezing combined with frozen storage might be potentially very useful for food industry to produce high quality starch-based ready to eat meals.

The production and properties of the biosurfactant synthesized by Bacillus subtilis CCTCC AB93108 were studied. The maximum concentration of the surfactant is 1.64 g/L when the bacteria grow in a medium supplemented with glucose as carbon sources. The isolated biosurfactant is a complex of protein and polysaccharide without lipids. It reduces the surface tension of distilled water to 45.9 mN/m, and its critical micelle concentration (CMC) is 2.96 g/L. It can stabilize emulsions of several aromatic and aliphatic hydrocarbons, such as benzene, xylene, n-pentane, n-nonane, gasoline and diesel oil. It presents high emulsification activity and stability in a wide range of temperature (4–100°C) and a long period of duration.

Sodium titanate nanotubes have been prepared and modified chemically with CdSe quantum dots (QDs) using bifunctional modifiers (HS-COOH). Their photovoltaic characteristics have also been studied. The results indicate that the surface photovoltage response of nanotubes extends to the visible light region, and the intensity of surface photovoltage is enhanced after modification with CdSe QDs. The field-induced surface photovoltage spectroscopy (FISPS) shows that sodium titanate nanotubes have different photovoltaic response before and after modification. That is, the surface photovoltaic response of pure sodium titanate nanotubes increases with the enhancement of positive applied bias and decreases with the enhancement of negative applied bias. Meanwhile, the surface photovoltaic response of CdSe modified sodium titanate nanotubes is different from that of the pure sodium titanate nanotubes. The whole spectrum increases with the enhancement of applied bias at the first stage. However, when the applied bias reaches a certain value, the surface photovoltage response keeps increasing in some spectrum regions, while decreasing in other spectrum regions. This novel phenomenon is explained by using an electric field induced dipole model.

Corn gluten meal is a major co-product of corn wet milling. Corn gluten meal was hydrolyzed with Alcalase, Flavourzyme, Alcalase+Flavourzyme and Flavourzyme+Alcalase. At the substrate concentration of 10%, corn protein hydrolysate catalyzed by Alcalase had a degree of hydrolysis of 17.83%, which was higher than that by Flavourzyme (3.65%). The hydrolysate catalyzed by Alcalase+Flavourzyme exhibited better antioxidant activities and was further purified. Three novel antioxidant peptides were purified by a series of chromatographic techniques. Sequences of the three peptides were identified as Cys-Ser-Gln-Ala-Pro-Leu-Ala, Tyr-Pro-Lys-Leu-Ala-Pro-Asn-Glu and Tyr-Pro-Gln-Leu-Leu-Pro-Asn-Glu, respectively. Among the three peptides, Cys-Ser-Gln-Ala-Pro-Leu-Ala exhibited good reducing power and excellent scavenging capacities for DPPH radical and superoxide anion radical, with IC50 values of 0.116 and 0.39mg/ml, respectively. The results from our study indicate antioxidant potency of corn protein hydrolysates and peptides separated from corn gluten meal and can provide basic understanding for the application of corn protein hydrolysates as natural antioxidants.