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Even distribution of core–shell heterojunction on porous catalyst supports is promising to get the super‐catalysts, yet laborious preparation hinders the wide application. A novel strategy of urea enzymolysis‐induced ions replacement is proposed for one‐pot loading of Bi12O17Cl2@Bi48Al2O75 core–shell heterojunction onto porous Al2O3 nanorod (named as Al2O3‐Bi12O17Cl2@Bi48Al2O75). The clever combination of urea enzymolysis and precipitation reactions that consume the ions generated in urea enzymolysis can switch the “on‐off” of urease, and thus allow the precise controlling of the concentration and existence time of the ions, as well as ions replacement. It is the urea enzymolysis‐induced ions replacing strategy that can generate the unique structure of Al2O3‐Bi12O17Cl2@Bi48Al2O75, and it is the distinctive structure that can get the selectivity of 96% benzaldehyde with 90% benzyl alcohol (BA) conversion in the photocatalytic oxidation of BA. The ions replacement, the growth of Al2O3‐Bi12O17Cl2@Bi48Al2O75, and the photocatalytic mechanism are investigated in detail. This work highlights a novel and convenient strategy for one‐pot loading core–shell heterojunction onto porous nanorod support, unveils a fresh biosynthesis of nanomaterials with elaborate structure, and thus paves the way for wide application of elaborate nanomaterials. [ABSTRACT FROM AUTHOR]

Aphids, the important global agricultural pests, harbor abundant resources of symbionts that can improve the host adaptability to environmental conditions, also control the interactions between host aphid and natural enemy, resulting in a significant decrease in efficiency of biological control. The facultative symbiont Serratia symbiotica has a strong symbiotic association with its aphid hosts, a relationship that is known to interfere with host–parasitoid interactions. We hypothesized that Serratia may also influence other trophic interactions by interfering with the physiology and behavior of major predators to provide host aphid defense. To test this hypothesis, we investigated the effects of Serratia on the host aphid Acyrthosiphon pisum and its predator, the ladybeetle Propylaea japonica. First, the prevalence of Serratia in different A. pisum colonies was confirmed by amplicon sequencing. We then showed that harboring Serratia improved host aphid growth and fecundity but reduced longevity. Finally, our research demonstrated that Serratia defends aphids against P. japonica by impeding the predator's development and predation capacity, and modulating its foraging behavior. Our findings reveal that facultative symbiont Serratia improves aphid fitness by disrupting the predation strategy of ladybeetle larvae, offering new insight into the interactions between aphids and their predators, and providing the basis of a new biological control strategy for aphid pests involving the targeting of endosymbionts. [ABSTRACT FROM AUTHOR]

Aminosilanized magnetic carbon microspheres as a novel adsorbent were designed and fabricated. The adsorbent was used for the magnetic solid-phase extraction of bisphenols at trace levels from environmental water samples before liquid chromatography with tandem mass spectrometry analysis. The structure, surface, and magnetic behavior of the as-prepared aminosilanized magnetic carbon microspheres were characterized by elemental analysis, scanning electron microscopy, transmission electron microscopy, Fourier transform infrared spectroscopy, powder X-ray diffraction, and vibrating sample magnetometry. The effects of the experimental parameters were investigated by the Plackett-Burman design, and then the parameters that were significant to the extraction efficiencies were optimized through a response surface methodology. The aminosilanized magnetic carbon microspheres exhibited high adsorption efficiency and selectivity for bisphenols. Under optimal conditions, low limits of detection (0.011-2.22 ng/L), and a wide linear range (2-3 orders of magnitude), good repeatability (4.7-7.8%, n = 5), and reproducibility (6.0-8.3%, n = 3) were achieved. The results demonstrate that the novel adsorbent possesses great potentials in the determination of trace levels of bisphenols in environmental water samples. [ABSTRACT FROM AUTHOR]

A novel decentralised direct adaptive fuzzy controller design is presented for a class of large-scale nonaffine uncertain nonlinear systems in this article. By integrating a fuzzy logic system and H ∞ tracking technique, the designed controller is able to adaptively compensate for interconnections and disturbances with unknown bounds, but none of the control and adaptation laws contains a sign function so that control chattering can be shunned. The closed-loop large-scale system is guaranteed to be asymptotically stable and obtain good H ∞ tracking performance. The control approach developed is applied to the following control problem of a string of vehicles within an automated highway system (AHS) and simulation results verify its validity. [ABSTRACT FROM AUTHOR]

In this article, a novel high gain observer (HGO)-based decentralised indirect adaptive fuzzy controller is developed for a class of uncertain affine large-scale nonlinear systems. By the combination of fuzzy logic systems and an HGO, the state variables are not required to be measurable. The proposed feedback and adaptation mechanisms guarantee that each subsystem is able to adaptively compensate for interconnections and disturbances with unknown bounds. It is ascertained using a singular perturbation method that all the signals of the closed-loop large-scale system stand uniformly ultimately bounded and the tracking errors converge to tunable neighbourhoods of the origin. Simulation results of correlated double inverted pendulums substantiate the effectiveness of the proposed controller. [ABSTRACT FROM PUBLISHER]

Abstract: Using the bleaching of the free radical scavenger 1,1-diphenyl-2-picrylhydrazyl (DPPH) as the guiding assay, a novel compound, 4-(3-(3,4-dihydroxyphenyl)acryloyl)-6-hydroxy-1-methoxy-1,2,3,4-tetrahydronaphthalene-2-carboxylic acid, was isolated from water-soluble extract of Canna edulis Ker with ten known compounds: rosmarinic acid, salvianolic acid B, ferulic acid, caffeic acid, 1-caffeoylquinic acid, 3-caffeoylquinic acid, 4-caffeoylquinic acid, 5-caffeoylquinic acid, salicylic acid and gallic acid. The structures were characterized by spectroscopic methods including extensive 2D-NMR techniques. Moreover, antioxidant activities of total extract and the new compound were determined through six different kinds of modes. In view of antioxidant activity confirmed, C. edulis extract and the new compound can be developed as natural food additives. In addition, the correlations between concentration and antioxidant activity and among the modes were analyzed. The results of DPPH and ABTS radical scavenging and FRAP assay exhibited high consistency. However, those for other modes showed difference to a certain extent. [Copyright &y& Elsevier]

Soluble dietary fiber (SDF) was prepared from Canna edulis Ker by-product by physical-enzymatic method and its structure was characterized using GC, FT-IR, 1H-NMR, and solid 13C-NMR spectroscopy. The results exhibit that SDF is mainly composed of polysaccharides with minor phenolic compounds. Moreover, influences of SDF on protease hydrolysis of β-lactoglobulin (β-lg) and lipase hydrolysis of tributyrin (TBG) were determined. The results indicate that SDF promotes N release of β-lg by pepsin, despite it inhibiting the enzymatic activity of pepsin. Inversely, tryptic hydrolysis of β-lg is inhibited by the addition of SDF, which has no obvious effect on tryptic activity. SDF also inhibits lipase hydrolysis of TBG and the inhibition rate increases with increasing SDF concentration. Furthermore, antioxidant activities of SDF were evaluated by six different modes, and the relationship between concentration and activity was discussed. The results indicated different activities determined by different methods, suggesting that antioxidant mechanisms of SDF are complicated. [ABSTRACT FROM PUBLISHER]

ABSTRACT Polyphenol oxidase (PPO) extracted from Canna edulis Ker rhizome was investigated. The substrate specificity was established as catechol > caffeic acid > chlorogenic acid > gallic acid > catechin. The optimum temperature and pH of the PPO activity were 20C and 6.8, respectively. The PPO was sensitive to many general inhibitors including C. edulis stem extract. Through response surface design, optimized inhibitor combination, containing 200 mg/L of citric acid, 284 mg/L of ascorbic acid, 67 mg/L of ethylenediaminetetraacetic acid and 8,000 mg/L of C. edulis stem extract, was obtained. With 96.73% of inhibition rate, the inhibitor combination could be developed as a natural additive used in the process of food preservation in the sight of safety of C. edulis aboveground part confirmed by animal experiment. In addition, the optimized inhibitor combination increased total phenol content and antioxidant activity of C. edulis rhizome. PRACTICAL APPLICATION In the sight of fresh food preservation influenced by polyphenol oxidase, additives are necessary to prevent the oxidation of polyphenol which is usually being in all fresh fruit and vegetable. The chemical synthesized additives always have various side effects and it has become a hot topic to research, and develop natural food additive with antioxidant activity. However, natural additives commonly have poor antioxidant activity. Therefore, it is a good choice to study interaction between natural extract and different chemical compounds and to develop inhibitor combination containing natural extract as main component. In this study, the optimized inhibitor combination (including 93.56% Canna edulis stem extract) was obtained through response surface design with an inhibition effect as high as 96.73%. The inhibitor combination could be developed as a natural additive used in the process of food preservation. [ABSTRACT FROM AUTHOR]

Canna edulis Ker starch was modified by heat-moisture treatment at moisture levels ranging from 18 to 27 g/100 g starch and its physicochemical properties were investigated. Amylose content, swelling power, solubility as well as water and oil absorption capacity in native starch were higher than in all treated starches. However, alkaline water retention and acid susceptibility of native starch were lower, along with different extent of amylose leaching. The result in the X-ray diffraction measurement revealed that the crystalline type of the starch gradually changed from B-type to A-type, and the degree of crystallinity changed. Investigation on thermal properties showed that the gelatinization enthalpy decreased, whereas the onset temperature, peak temperature, concluding temperature and transition temperature range increased in modified starch than in native starch. In addition, all modified starches exhibited remarkably low values of peak viscosity, hot pasting viscosity and final viscosity, compared to those of native starch. [ABSTRACT FROM AUTHOR]

Canna edulis Ker by-product was recycled and utilized after starch extraction. The chemical composition, physical properties and antioxidant activity of the by-product were investigated. The by-product was mainly composed of dietary fiber (54.84% measured by AOAC method), and the insoluble dietary fiber constituted the major fraction. Then, the chemical composition of dietary fiber was tested using modified AOAC and Englyst methods. The results showed that dietary fiber was comprised of cellulose, hemicelluloses (including xyloglucans, arabinoxylans and glucuronoxylans), pectin and lignin. Moreover, the by-product contained relatively high content of phenolic compounds and exhibited a moderate antioxidant activity. In addition, the by-product showed both high water-holding capacity (12.5 mL/g) and oil-holding capacity (14 mL/g), and its suspension exhibited controllable viscosity. Therefore, the by-product from C. edulis is not only a source of dietary fiber but also a functional ingredient for food industry. [ABSTRACT FROM PUBLISHER]

Spontaneous vesicles of dicetyl dimethyl ammonium chloride (DCDAC) and its mixture with sodium bis-(2-ethylhexyl) sulfosuccinate (AOT) are observed respectively in ethanol-water mixed solvents, which have been demonstrated by negative-staining transmission electric microscope (TEM) and atomic force microscope (AFM). Ethanol can promote the vesicle formation, especially to pure DCDAC surfactant system. The entrapment efficiency of the vesicles to all-trans retinoic acid (ATRA) was measured by the first order derivative spectrophotometry method. The entrapment efficiency of ATRA reaches 22% in 0.5 ethanol volume ratio solution when the concentration of DCDAC is 2.5 × 10-3 mol/L. In the same solvents, the entrapment efficiency could be as high as 62% in 1:9 (molar ratio) DCDAC/AOT mixtures when the total concentration of surfactants is 3.0 × 10-3 mol/L. [ABSTRACT FROM AUTHOR]

By using the quantitative structure-property relationship (QSPR) method, the relationship between the hydrophilic-lipophilic balance (HLB) value and the chemical structure of surfactants were studied for nonionic surfactants of the ethoxylated alcohols and ethoxylated alkylphenols, for which the number of EO groups is less than 20. The obtained best QSPR model contains only two simple descriptors. One is zero order of Kier-Hall index (KH0); the other is the number of oxygen atoms in the hydrophilic group (No). The correlation coefficient (R2) is as high as 0.984. The resulted QSPR model shows a significantly higher accuracy with respect to the effective chain length method. [ABSTRACT FROM AUTHOR]

Abstract: Response surface methodology was employed to study phosphorous (P) and resistant starch (RS) content of resistant Canna edulis Ker starch phosphate monoester by starch phosphorylation with sodium mono- and dihydrogen orthophosphate. A five-level-four-factor central composite design was used for maximizing the P and RS content. The optimal reaction conditions obtained were NaH2PO4·2H2O to Na2HPO4·12H2O molar ratio of 1:0.44, phosphate sodium to starch weight ratio of 1.76:1, reaction temperature of 131.6°C and reaction time of 2.43h. The theoretical P and RS content were attained to about 0.58 and 73.17%, respectively. P and RS content experimentally obtained were 0.55 and 71.93%, in agreement with the predicted values. In addition, the structural characteristic of the purified starch phosphate monoester was investigated by 31P-nuclear magnetic resonance (31P-NMR), fourier transform-infrared spectroscopy (FT-IR), X-ray powder diffraction (XRD) and scanning electron microscopy (SEM). [Copyright &y& Elsevier]

The interaction of alkyl sulfate surfactant with water molecules was studied by using DFT. It was revealed for the first time that alkyl sulfate surfactant formed stable hydrate with six water molecules when it was saturation adsorption at the air-water interface. The influence of alkyl chain length on the hydration area and the structure of hydrophilic group of complexes CH3 [image omitted](H2O)6 (m = 0-8) was investigated. The calculated results showed that: (1) the hydration area of the hydrophilic group was 53.6 Å2, which was in good agreement with the experimental results; (2) change in the length of alkyl chain had almost no effect on the structure and hydration area of the hydrophilic group. [ABSTRACT FROM AUTHOR]

A W/O microemulsion of Tween-80-Span-80/n-butylalcohol/ethyl-oleate/H2O to envelop insulin (INS) was prepared. In order to obtain the maximum solved water, the components of microemulsion to envelop INS were chosen with the pseudo-ternary phase diagram and the influences of temperature, salinity as well as the pH on microemulsion areas also were investigated. To test the properties of the microemulsion, the conductance was used to divide O/W, W/O and BC regions, the dynamic light scattering to evaluate the particle diameters of microemulsion, the 125I isotope tracing method to measure the release rate of INS loaded in W/O microemulsion, and the growth inhibitory effect test to appraise the cytotoxicity on human normal cells. Results show that W/O microemulsion forms when water content below 50% in the microemulsion system. The microemulsion region decreases slightly with the increase of temperature, salinity and the decrease of pH. However, the viscosity measurements along certainly selected dilution lines to the microemulsion indicate that no phase invert occurred. Diameter of microemulsion particle increases with the addition of INS, and the increase is sharp in the first 5 days then very slightly at 68.6 nm within a month. The INS loaded W/O microemulsion possesses eminent sustaining release efficiency and the cytostatic as well as cytotoxic assays illustrate that the microemulsion can be used as drug delivery at small dosage. [ABSTRACT FROM AUTHOR]