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关键词： digestibility   FTIR spectroscopy   glycaemic index   starch  

摘要： Starch is the largest constituent in animal diets. The aims of this study were as follows: (a) to assess the variability of basic physicochemical properties and in vitro starch digestion of starchy feedstuffs and investigate relationship between physicochemical properties and starch digestion of the feedstuffs, and (b) to explore the effects of different sources of starchy feedstuffs on starch digestion and glucose release. In this study, we determined the inherent molecular structure and granular structure of starch and chemical compositions of seven starchy feedstuffs, as well as starch digestion in single feedstuff and different feedstuffs combined with corn. Scanning electron microscope (SEM) results revealed significant difference between granule shape and size of starch of different feedstuffs. Fourier transforms infrared (FTIR) spectra for barley and wheat had lower (p < 0.05) absorbance band at areas A_860 and A_928 than other feedstuffs, yet rice starch had the lowest value for ratio (R) (1047/1022). Moreover, digestion rate ranged from 0.0157/min for resistant starch (sorghum) to 0.029/min for rapidly starch (broken rice). The principle component analysis (PCA) showed that predicted glycaemic index (pGI) was positively related to A_1022, glucose and rapidly (RDS) content and negatively related to A_995, A_1047, R (1047/1022), resistant starch (RS) and amylose content. Most of the feedstufss with corn combination had no effect on rate of starch digestion. In addition, different starchy feeds and corn combination changed the rate of starch digestion, when barley, however, sorghum combined with corn seemed to affect rate of starch digestion. To sum up, different sources differed in basic physicochemical and structural properties, which would influence the digestion rate of starch and the release of glucose. Combination of different feedstuffs particular sorghum with corn has interactive effect on starch digestion and the release of glucose.

关键词： Acheta domesticus   Gryllus assimilis   Freeze drying   Oven drying   Nutritional characteristics   Volatile compounds  

摘要： Edible insects are repeatedly being considered as underutilized food candidate due to their high nutritional value. Although frequent acceptance of whole insects to consumer is still challenging, incorporation of insects in food as powder or paste has been suggested to increase their acceptability. Hence, Acheta domesticus and Gryllus assimilis were subjected to freeze drying, oven drying, and blanching to acquire a clear insight on the impact of the processing methods on the nutritional and physical properties of both species. Result showed that these three methods had limited effects on the proximate composition, fatty acid and amino acid profile but had significant impact on other parameters for both species. Vitamin B12 in A. domesticus did not change but G. assimilis changed due to the treatment. Freeze drying showed better lightness (L* value) and lower browning index for both cricket species. Oven drying and blanching resulted in lower lipid oxidation values than freeze drying for both cricket species;though lipid oxidation was in all cases well below the rejection limit. Esters were the predominant group of volatile compound in freeze and oven-dried cricket while least amount of volatiles were found in blanched cricket. The volatiles resulted from fatty acid oxidation were higher in freeze-dried crickets, while Maillard reaction products were found in oven-dried samples. Although freeze drying showed higher colour quality, oven drying exerted superior effect in terms of nutritional and flavour characteristics followed by blanching treatment.

关键词： Hydrothermal synthesis   Biomass   Hydrochar   XPS   FTIR   Solid state NMR  

摘要： Seven different lignin samples, three from Kraft extraction and four from organosolv extraction, were subjected to hydrothermal treatment at 260? for four hours to assess the impact of lignin type on the physicochemical properties of the hydrothermal material. The 13C Solid state NMR, XPS, FTIR and SEM analysis revealed that the different sources of lignin and the extraction conditions created variations in the degree of syringyl and guaiacyl subunits, inter-unit bonding arrangements, morphology and surface composition. Hydrothermal carbonization appeared to ?normalize? the differences between each of the lignin samples, via breaking ?-O-4 or ?-O-4 linkages, removal of methoxy and syringyl subunits, and creation of C?C and 4-O-5 linkages to polymerization into large 100-200 ?m amorphous carbon particles. Overall, this study indicates that the source and extraction type have minimal influence on the physicochemical structure and morphology of the final hydrothermal product.

关键词： titanium dioxide   sol-gel method   photocatalysis   hetero(arenes)   oxidative S-N(H) cross-coupling  

摘要： Nanostructured titanium dioxide (TiO2) with a crystallite size from 10 to 85 nm, photocatalytically active for organic reactions under illumination with visible light, has been prepared by a sol-gel process using a titanium tetrabutoxide solution in ethanol with an initial pH of 6. According to X-ray diffraction characterization results, the as-prepared titanium dioxide was amorphous. Annealing in a hydrogen atmosphere for 1 h at 400 degrees C led to the formation of an anatase phase, and annealing in the temperature range from 600 to 800 degrees C resulted in the anatase-rutile phase transition. The crystallite size of titanium dioxide increased from 10 to 75 nm as the annealing temperature was raised from 400 to 1000 degrees C (furnace annealing for 1 h) and from 60 to 85 nm as the annealing time at a temperature of 800 degrees C was increased from 30 to 240 min. Diffuse reflection spectra showed that the band gap of TiO2 decreased from 3.3 to 2.6 eV as the annealing temperature was raised from 200 to 1000 degrees C. The specific surface area data obtained by BET measurements showed that the samples annealed at the highest temperature (1000 degrees C) had the smallest surface area, which dropped from 307 to 1 m(2)/g. The efficiency of the synthesized TiO2 tested as a catalyst for oxidative S-N(H) cross-coupling of acridine with indole demonstrated an in crease in product yield from 35 to 80% as the annealing temperature was raised to 800 degrees C. Varying the 800 degrees C annealing time from 30 to 180 min had no effect on the reaction product yield, which ranged from 70 to 80%.

关键词： Soil quality   Physico-chemical properties   Nematode indices   Functional indicators   Biofunctool (R)   Co-inertia analysis  

摘要： The assessment of the impacts of land management on soil quality is crucial in the current environmental context. Among the many approaches available to assess soil quality, most of studies or monitoring programs consist in the measurement of stocks using an additive approach of physical, chemical and biological, parameters. More recently, functional methods have been developed to provide tools which better account the abioticbiotic interactions. The objective of our study was to evaluate and compare the capacity of physico-chemical, biological and functional parameters to assess the effect of land management on soil quality over a gradient of disturbance based on rubber tree plantations in Chachoengsao province, Thailand. Three sets of indicators were applied based on i. soil physico-chemical analyses, ii. biological analyses, based on soil free-living nematode indices iii. functional analyses, with Biofunctool (R) indicators linked to three main soil functions (carbon transformation, nutrient cycling, soil structure maintenance). A soil quality index resulting from the aggregation of each set of indicators into a single score showed that functional assessment was the most sensitive to the gradient of disturbance. Co-inertia analysis between sets revealed a significant relationship between functional analysis and both physico-chemical and biological sets of indicators, whereas the two latter were not related. Our results validated the ability of the functional method to better reflect the complexity of the abiotic-biotic interactions of the soil system.

关键词： Chlorhexidine   Nanoparticles   Root canal sealers  

摘要： Objective. The aim of this study was to evaluate the influence of the incorporation of chlorhexidine-hexametaphosphate nanoparticles (CHX-HMP NPs) on antibacterial, cyto-toxic and physicochemical properties of AH Plus (AH), MTA Fillapex (MTA) and Pulp Canal Sealer (PCS). Methods. The NPs were synthesized and characterized by Scanning Electron Microscopy (SEM), Dynamic Light Scattering (DLS), zeta potential, Atomic Force Microscopy (AFM) and Energy-Dispersive X-ray Spectroscopy (EDS). The incorporation was made by weight, 2% and 5% of NPs. The antimicrobial activity, cytotoxicity, flow, radiopacity, setting time, solu-bility and pH were evaluated. The statistical analysis was performed by two-way analysis of variance test and Tukey post hoc test (P < 0.05). Results. SEM analysis showed the tendency for CHX-HMP NPs to cluster, the effective mean diameter measured by DLS: 169.39 nm and the zeta potential:-10.18 mV. The NPs were indi-vidually measured by AFM: 22.99?52.75 nm. EDS analysis identified the presence of C, N, O, Na, P, Cl. After incorporation: The Direct Contact Test showed an increase in the antimi-crobial action of AH, PCS and MTA;the sealers showed a decrease in flow and at 24 h of immersion also an increase in solubility, but did not affect the radiopacity of the samples;AH setting time increased and MTA did not reach setting under any of the conditions tested. All samples showed a decrease in pH value as the immersion time progressed. Significance. The incorporation of NPs can improve the antimicrobial performance of endodontic sealers without impairing other biological and physicochemical properties. ? 2021 The Academy of Dental Materials. Published by Elsevier Inc. All rights reserved.

关键词： Maillard reaction   Egg white   Alkali   Physicochemical properties   Antioxidant activity  

摘要： Maillard reaction was progressed by incubating the mixture of egg white (EW) and alkali at different temperatures (4 degrees C, 25 degrees C and 37 degrees C) for different days (0, 1, 3, 5 and 7 days), to explore the effects of temperatures and incubating days on physicochemical and antioxidant properties of EW during the treatment of alkali. The results revealed that the color, browning intensity and fluorescence intensity increased with the extended incubating days (P < 0.05), whereas the pH value declined (P < 0.05). The absorbance at 294 nm increased first, and then decreased with the prolonged incubating days (P < 0.05). SDS-PAGE and FTIR showed that Maillard reaction had occurred in EW during the treatment of alkali. Cysteine was the main amino acid involved in the Maillard reaction. The reducing power, ABTS radical scavenging activity and Fe2+ chelating activity of Maillard reaction products (MRPs) increased on the first day of incubation then decreased with the increasing incubating days. Temperature had a pronounced effect on the physicochemical properties of EW and the antioxidant activities of MRPs during the treatment of alkali.

关键词： Protein oxidation   Amino acid   Aggregation   Molecular weight   Antioxidant activity  

摘要： Protein oxidation can influence the quality of food during processing and storage. This study examined the changes in physicochemical properties and in vitro digestibility of egg white protein (EWP) oxidized with a peroxyl-radical-generating system (2,2'-azobis(2-amidinopropane) dihydrochloride (AAPH) simulating the oxidation environment of industrial processing. With the increasing AAPH concentration, all amino acid contents and protein solubility decreased, the carbonyl content almost doubled increased, free sulfhydryl content almost decreased by three quarters. The essential amino acids, such as phenylalanine, leucine, threonine, histidine was particularly sensitive towards oxidation, decreased by more than 10% after EWP oxidized by 5.0 mmol/L AAPH. Volume of larger soluble aggregates formed by AAPH increased, and the digestibility of EWP, decreased with the increase of oxidation degree. Molecular weight analysis showed that the content and antioxidant activity of low molecular weight peptides obtained by pepsin hydrolysis or trypsin hydrolysis was gradually reduced with the increase of the degree of oxidation, which indicated that the nutritional and biological activity of EWP was reduced by oxidation. These results may help to understand the changes in the functional and nutritional quality of egg-based foods that involve oxidation during processing.

关键词： Artificial ripening   Chlorophylls   Carotenoids   Vitamin C   Tannin   Pectin  

摘要： The study evaluates effects of selected two types of induced ripening agents;ethephon and acetylene on biochemical parameters of banana (Musa acuminata, AAB). Bananas at fully green stage were treated with 1000 ppm ethephon and 1000 ppm acetylene. A series of biochemical parameters including vitamin C, tannin, pectin and pigments (chlorophylls and carotenoids) were analyzed. It is revealed that fruit firmness, total sugar and vitamin C are greatly affected by ethephon and acetylene treatments whereas ethephon causes nearly 50% loss of vitamin C at eat ripe stage (Stage 6). Out of the parameters tested peel colour, pulp to peel ratio, moisture content in peel, titratable acidity (TA) % and total starch in flesh were not significantly (p > 0.05) affected by the treatments. Acetylene treatment caused significantly (p > 0.05) low level of moisture content in flesh, high level of tannin and pectin at stage 6. Treated banana contained high levels of chlorophyll a and chlorophyll b whereas significantly low levels of total carotenoids were detected in both peel and flesh in treated banana.

关键词： cryochemical modification of drugs   combined cryochemical method   nanoparticles and nanoforms of drugs   dioxidine  

摘要： A combined cryochemical method is proposed for the dimensional and structural modification of drugs. This method forms a molecular flow of a substance combined with a flow of carrier gas, with subsequent condensation of the substance's molecules on a cold surface. This method is used to synthesize nanoforms of the dioxidine antibacterial drug. The molecular structure of the drug is found to remain unaltered during the cryochemical dimensional and structural modification. A regular decrease in the particle size and a change in the phase composition of the cryochemically modified dioxidine with an increase in the carrier gas (carbon dioxide, CO2) flow rate are shown.