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1.
The phenolic compounds, color and antioxidant capacity of gluten-free pasta prepared with non-conventional flours such as chickpea (CHF), unripe plantain (UPF), white maize (WMF) and blue maize (BMF) were analyzed. Fifteen phenolic compounds (five anthocyanins, five hydroxybenzoic acids, three hydroxycinnamic acids, one hydroxyphenylacetic acid and one flavonol) were identified in pasta prepared with blue maize, and 10 compounds were identified for samples prepared with white maize. The principal component analysis (PCA) led to results describing 98% of the total variance establishing a clear separation for each pasta. Both the proportion (25, 50 and 75%) and type of maize flour (white and blue) affected the color parameters (L*, C ab *, h ab and ΔE* ab ) and antioxidant properties (DPPH, ABTS and FRAP methods) of samples, thus producing gluten-free products with potential health benefits intended for general consumers (including the population with celiac disease).  相似文献   

2.
In this study, the tetramido macrocyclic iron complex (Fe-TAML) was successfully synthesized, and then it was characterized using 1H nuclear magnetic resonance (1H NMR), electrospray ionization mass spectrometry (EIS-MS) and elemental analysis. An activated peroxide system was established for low-temperature bleaching of cotton by combining the synthesized catalyst (Fe-TAML) with hydrogen peroxide. Experimental results showed that the Fe-TAML/H2O2 bleaching system exhibited effective bleaching performance in the use of 2 μM Fe-TAML, 20 g/l H2O2, 1 g/l NaHCO3, 2 g/l scouring agent and 2 g/l wetting agent at 60 °C for 60 min. In comparison with the conventional bleaching system, the Fe-TAML/H2O2 system provided bleached cotton with a superior degree of whiteness, higher tensile strength and acceptable water absorbency. The application of Fe-TAML was expanded and the activated peroxide system may provide a green approach for the cotton bleaching.  相似文献   

3.
L-cysteine (Cys) and silver nanoparticles (Ag NPs) were successfully linked onto the cotton fabric surfaces. The Cys molecules were covalently linked to the cotton fibers via esterification with the cellulose hydroxyl groups, and the Ag NPs tightly adhered to the fiber surface via coordination bonds with the Cys thiol groups. As a result, the Ag NPs coating on the cotton fabric showed an excellent antibacterial function with an outstanding laundering durability. The bacterial reduction rates (BR) efficiency reached 100 % for Escherichia coli (E. coli) and Staphylococcus aureus (S. aureus). After 50 consecutive laundering cycles, the bacterial reduction rates (BR) against E. coli and S. aureus were maintained over 97 %. It has potential applications in a wide variety of fields such as sportswear, socks, and medical textile.  相似文献   

4.
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5.
In this study, natural dyes were extracted from five plants, namely diospyros kaki, dioscorea cirrhosa, millettia (jixueteng), ecliptae, and macrocarpa nucuma, using environmentally-friendly solvents, including ethanol and deionized (DI) water. A plant mordant, tannin extracted from Emblica officinalis G., and a metal mordant, copper sulfate, were used in the pre-dyeing process. Cotton and silk fabric samples were treated using the five natural dyes without and with mordanting for comparison on their color strength and characteristics as well as protection against ultraviolet radiation (UVR). Results revealed that Emblica officinalis G. had the highest total phenol content, followed by dioscorea cirrhosa. The presence of abundant phenolic groups in the natural dyes and mordant makes them effective coloration agents for fabrics. Cotton and silk fabrics dyed using ecliptae without pre-mordanting had the highest K/S values. Silk fabrics had higher K/S values than cotton fabrics, indicating greater color strength in pre-mordanted silk treated with DI water-extracted dyes. Natural mordant used before treatment with natural dyes contribute to significant enhancement in color strength, and Emblica officinalis G. alone could darken the color of cotton and silk fabrics dyed with plant pigment. Moreover, treatment with natural dyes after mordanting can increase ultraviolet protection factor (UPF) and the enhancement in UVR protection is greater and more significant in cotton fabrics than in silk fabrics, and in fabrics treated with DI water-extracted natural dyes than in those treated with ethanol-extracted ones. In conclusion, pre-dyeing with natural mordant followed by treatment with natural dyes extracted using environmentally-friendly solvents can enhance significantly K/S and UPF, offering directions for manufacturing textiles without environmental hazards but with good appearance and health benefits.  相似文献   

6.
In order to prepare antimicrobial regenerated cellulose fibers from blended spinning solutions, three non-water soluble polymeric guanidine derivatives, polyhexamethylene guanidine dodecyl benzene sulfonate (PHGDBS), polyhexamethylene guanidine dodecyl sulfate (PHGDSA), and polyhexamethylene guanidine laurylsulfonate (PHGLSO) were synthesized. And the chemical structure of these agents was verified by element analysis, Fourier transform infrared spectroscopy (FTIR), and proton nuclear magnetic resonance (1H-NMR). The antimicrobial activity of the three agents as well as cellulose films containing PHGDBS was also studied. The results showed that the compounds we prepared had strong properties against both bacterial and fungus, including Staphylococcus aureus (S. aureus), Escherichia coli (E. coli), Candida albicans, and Aspergillus niger. Moreover, it was found that three antimicrobial agents were insoluble in water but they can dissolve in solvents of cellulose such as 1-butyl-3-methylimidazolium chloride ([BMIM]Cl) and N-methylmorpholine-N-oxide monohydrate (NMMO·H2O). Meanwhile, it was also proved that [BMIM]Cl had little effect on the antimicrobial properties of these agents. The cellulose films containing only 1.0 wt% PHGDBS showed 99.94 % and 96.95 % bacterial reduction rates for S. aureus and E. coli, respectively. Moreover, still over 91 % of bacterial reduction was maintained after 15 laundering cycles. It suggests that the three agents will be suitable to prepare antimicrobial regenerated cellulose fibers or films.  相似文献   

7.
4-Amino-double(octadecyldimethyl ammonium chloride)-1,2,4-triazole (ADAC-TZ), a gemini cationic auxiliary with a heterocyclic triazole structure, was designed and synthesized by the method described here and characterized for use in the cold pad batch dyeing of cotton knits. The results show that, for ADAC-TZ, the critical micelle concentration (CMC) is 4.0×10-4 mol/l, the Krafft point is 29.8 °C, the foam height is only 169 mm/5 min, and the solubilization for toluene is 6.67 ml/g, which means that ADAC-TZ exhibits excellent low-foaming, water solubility and solubilization properties. The present research also demonstrates that ADAC-TZ pretreatment can increase the K/S value, dye fixation, and color fastness to washing and rubbing of cotton knits dyed through BES reactive dye cold pad batch dyeing used in combination with the alkaline agent QF-4.  相似文献   

8.
Based on data collected from rice fields under drying–wetting cycle condition, the procedure of dual-crop coefficient (K cd) approaches was calibrated and validated to reveal its feasibility and improve its performance in rice evapotranspiration (ET c) estimation. It was found that K cd based on FAO-recommended basal crop coefficients (K cb) underestimated dual-crop coefficients in monsoon climate region in East China. The recommended coefficient (K cp) value of 1.2 was not high enough to reflect the pulse increase of rice ET c after soil wetting. The K cb values were calibrated as 1.52 and 0.63 in midseason and late season, and the K cp value was adjusted as 1.29 after soil wetting in rice field under drying–wetting cycle condition. The dual-crop coefficient curves based on locally calibrated K cbCal and K cpCor matched well with the measured crop coefficients and performed well in calculating rice evapotranspiration from paddy fields under drying–wetting cycle condition. So it can be concluded that the procedure of dual-crop coefficient method is feasible in rice ET c estimation, and locally calibrated K cb and K cp can improve its performance remarkably.  相似文献   

9.
The precise level of environmental control in vitro may aid in identifying genetically superior plant germplasm for rooting characteristics (RC) linked to increased foraging for plant nitrogen (N). The objectives of this research were to determine the phenotypic variation in root morphological responses of 49 Solanum chacoense (chc), 30 Solanum tuberosum Group Phureja – Solanum tuberosum Group Stenotomum (phu-stn), and three Solanum tuberosum (tbr) genotypes to 1.0 and 0.5 N rate in vitro for 28 d, and identify genotypes with superior RC. The 0.5 N significantly increased density of root length, surface area, and tips. All RC were significantly greater in chc than in either phu-stn or tbr. Based upon clustering on root length, surface area, and volume, the cluster with the greatest rooting values consisted of eight chc genotypes that may be utilized to initiate a breeding program to improve RC in potato.  相似文献   

10.
New applications call for many new requirements. In order to improve the toughness of aldehyde hyaluronic acid (A-HA) and adipic acid dihydrazide (ADH) hydrogel, the poly(ethylene glycol) (PEG) was added. PEG content and molecular weight have little effect on the gelation time, and the composite hydrogels can form in situ within 20 seconds at room temperature. The press test showed that the hydrogels containing PEG possessed a better compression resistance, after pressed more than five times, the composite hydrogels could restore. Rheological properties were measured to evaluate the working ability and the effect of PEG on hydrogels. By analyzing the shear viscosity (η γ=0.01), yield stress (σ 0) and threshold shear stress (σ c ), the addition of PEG can make the structure of composite hydrogels get loose and improve the shear resistance. Especially, PEG800 can enhance the antishear ability obviously. The amplitude sweep tests showed a broad linear viscoelastic region, indicating a wide processing range. In the meanwhile, we also found that PEG can improve the optical transmittance of xerogel evidently.  相似文献   

11.
Water management is an important factor in regulating soil respiration and the net ecosystem exchange of CO2 (NEE) between croplands and atmosphere. However, how water management affects soil respiration and the NEE of paddy fields remains unexplored. Thus, a 2-year field experiment was carried out to study the effects of controlled irrigation (CI) during the rice season on the variation of soil respiration and NEE, with flooding irrigation (FI) as the control. A decrease of irrigation water input by 46.39% did not significantly affect rice yield but significantly increased irrigation water use efficiency by 0.99 kg m?3. The soil respiration rate of CI paddy fields was larger than that of FI paddy fields except during the ripening stage. Natural drying management during the ripening stage resulted in a significant increase of the soil respiration rate of the FI paddy fields. Variations of NEE with different water managements were opposite to soil respiration rates during the whole rice growth stages. Total CO2 emission of CI paddy fields through soil respiration (total R soil) increased by 11.66% compared with FI paddy fields. The increase of total R soil resulted in the significant decrease of total net CO2 absorption of CI paddy fields by 11.57% compared with FI paddy fields (p < 0.05). There were inter-annual differences of soil respiration and the NEE of paddy fields. Frequent alternate wetting and drying processes in the CI paddy fields were the main factors influencing soil respiration and NEE. CI management slightly enhanced the rice dry matter amount but accelerated the consumption and decomposition of soil organic carbon and significantly increased soil respiration, which led to the decrease of net CO2 absorption. CI management and organic carbon input technologies should be combined in applications to achieve sustainable use of water and soil resources in paddy fields.  相似文献   

12.
Lupinus albus seeds contain conglutin gamma (Cγ) protein, which exerts a hypoglycemic effect and positively modifies proteins involved in glucose homeostasis. Cγ could potentially be used to manage patients with impaired glucose metabolism, but there remains a need to evaluate its effects on hepatic glucose production. The present study aimed to analyze G6pc, Fbp1, and Pck1 gene expressions in two experimental animal models of impaired glucose metabolism. We also evaluated hepatic and renal tissue integrity following Cγ treatment. To generate an insulin resistance model, male Wistar rats were provided 30% sucrose solution ad libitum for 20 weeks. To generate a type 2 diabetes model (STZ), five-day-old rats were intraperitoneally injected with streptozotocin (150 mg/kg). Each animal model was randomized into three subgroups that received the following oral treatments daily for one week: 0.9% w/v NaCl (vehicle; IR-Ctrl and STZ-Ctrl); metformin 300 mg/kg (IR-Met and STZ-Met); and Cγ 150 mg/kg (IR-Cγ and STZ-Cγ). Biochemical parameters were assessed pre- and post-treatment using colorimetric or enzymatic methods. We also performed histological analysis of hepatic and renal tissue. G6pc, Fbp1, and Pck1 gene expressions were quantified using real-time PCR. No histological changes were observed in any group. Post-treatment G6pc gene expression was decreased in the IR-Cγ and STZ-Cγ groups. Post-treatment Fbp1 and Pck1 gene expressions were reduced in the IR-Cγ group but increased in STZ-Cγ animals. Overall, these findings suggest that Cγ is involved in reducing hepatic glucose production, mainly through G6pc inhibition in impaired glucose metabolism disorders.  相似文献   

13.

Background

The rice Pi2/9 locus harbors multiple resistance (R) genes each controlling broad-spectrum resistance against diverse isolates of Magnaporthe oryzae, a fungal pathogen causing devastating blast disease to rice. Identification of more resistance germplasm containing novel R genes at or tightly linked to the Pi2/9 locus would promote breeding of resistance rice cultivars.

Results

In this study, we aim to identify resistant germplasm containing novel R genes at or tightly linked to the Pi2/9 locus using a molecular marker, designated as Pi2/9-RH (Pi2/9 resistant haplotype), developed from the 5′ portion of the Pi2 sequence which was conserved only in the rice lines containing functional Pi2/9 alleles. DNA analysis using Pi2/9-RH identified 24 positive lines in 55 shortlisted landraces which showed resistance to 4 rice blast isolates. Analysis of partial sequences of the full-length cDNAs of Pi2/9 homologues resulted in the clustering of these 24 lines into 5 haplotypes each containing different Pi2/9 homologues which were designated as Pi2/9-A5, ?A15, ?A42, ?A53, and -A54. Interestingly, Pi2/9-A5 and Pi2/9-A54 are identical to Piz-t and Pi2, respectively. To validate the association of other three novel Pi2/9 homologues with the blast resistance, monogenic lines at BC3F3 generation were generated by marker assisted backcrossing (MABC). Resistance assessment of the derived monogenic lines in both the greenhouse and the field hotspot indicated that they all controlled broad-spectrum resistance against rice blast. Moreover, genetic analysis revealed that the blast resistance of these three monogenic lines was co-segregated with Pi2/9-RH, suggesting that the Pi2/9 locus or tightly linked loci could be responsible for the resistance.

Conclusion

The newly developed marker Pi2/9-RH could be used as a potentially diagnostic marker for the quick identification of resistant donors containing functional Pi2/9 alleles or unknown linked R genes. The three new monogenic lines containing the Pi2/9 introgression segment could be used as valuable materials for disease assessment and resistance donors in breeding program.
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14.
This study was conducted to investigate the impact of water salinity (ECw) and sodicity (SARw) on saturated (Ks) and relative (Kr) hydraulic conductivities in two clay (C) and sandy clay loam (SCL) soils. The results showed that the Ks decreased with increasing SARw, and in all of water quality treatments, the Ks of SCL soil was higher than that of the C soil. Sodicity effect (even at high SARw) on the Kr of clay soil was minimized by high salinity. Although Kr of both soils similarly responded to ECw and SARw, microstructure of clay soil was more sensitive to water quality. Effect of ECw on soil structure was greater than that of SARw. In order to assess the applicability of artificial neural networks (ANNs) in estimating Ks and Kr, two types of FFBP and CFBP ANNs and two training algorithms, namely Levenberg–Marquardt (LM) and Bayesian regulation, were employed with two strategies of uniform threshold and different threshold functions. Multiple linear regressions were also used for Ks and Kr prediction. Based on the ANN results of second strategy, best topology (4–5–4–1) was belonged to CFBP network with LM algorithm, LOGSIG–LOGSIG–TANSIG threshold functions, and values of MAE and R2 are equal to 0.1761 and 0.9945, respectively. Overall, the efficacy of ANNs is much greater than regression method for Ks prediction.  相似文献   

15.
An epoxy resin (diglycidyl ether of bisphenol-A) was blended with different loadings of a glycidyl-polyhedral oligomeric silsesquioxane (POSS) and isothermally cured with an amine hardener at varying temperatures and times. The glass transition temperature (T g) of the samples was measured at different chemical conversions (α) using differential scanning calorimetry (DSC). Time-temperature shifts were made for T g vs. ln(time) data to be superposed at an arbitrary reference temperature in the kinetically controlled reaction regime, and these shift factors were used to obtain an Arrhenius activation energy. The influence of POSS on different reaction systems was investigated in terms of the T g-α relationship, which was fitted with two models; DiBenedetto and Venditti/Gillham equations. It was found that POSS molecules played different roles at different stages of the curing process. At lower conversions, the inorganic cage of the incorporated POSS (up to 20 wt%) reduced the mobility of the molecular segments, giving rise to an increase in T g. However, above the 20 wt% POSS, there was a depression of T g, which may be associated with a plasticizing effect of organic substituents of the POSS molecules. Moreover, the effect of POSS on T g became less pronounced when the conversion reached 0.8.  相似文献   

16.
In the present work, oil adsorption, desorption, and resorption of poly(lauryl methacrylate-co-hydroxyethyl methacrylate) P(LMA-co-HEMA) were evaluated with different oils by a gravimetric method. Adsorption kinetics were modeled using pseudo-first-order and pseudo-second-order equations. Polymer network parameters of P(LMA-co-HEMA) regarding average molecular weight (Mc) between two crosslink piontss can be calculated by oil absorbency at equilibrium (Q e ), the solubility parameter (δ) and polymer-solvent interaction parameter (χ) with Flory-Huggins relation. The results showed pseudo-second-order model has a better fit to the oil adsorption kinetic data The desorption can be analyzed by fitting a prediction of exponential-like decay to the deswelling curves. A typical oil desorption exhibited two stages: a burst release driven by concentration gradient, and a slow release controlled by diffusion and the elastic recovery of polymer networks. For reusability, the resorption behavior of P(LMA-co-HEMA) was also investigated. It was worth noting that oil resorption was faster than the first adsorption due to potential passages. Moreover, the adsorption capacity was not significantly changed after regeneration.  相似文献   

17.
We present a rapid, simple, convenient and cost-effective method for producing nanosized stable silver particles on cotton fibers with complete control of the silver loading level using a thermal reducing silver carbamate complex. Cotton gauze was coated with silver 2-ethylhexylcarbamate solution. Silver nanoparticles on the cotton gauze were characterized by energy dispersive X-ray spectroscopy and X-ray diffraction. Particle size and lattice image of the silver nanoparticles were studied by scanning electron microscopy. The antibacterial activity of the silver coated cotton gauze against Escherichia coli and Staphylococcus aureus, whole blood clotting and physical properties including vertical wicking test, water retention time and absorption of 0.9 % (w/v) saline were studied. Silver coated cotton gauze showed a faster blood clotting rate than the untreated cotton gauze. Cotton gauzes treated with two different silver concentrations (0.01 %, 0.1 %) showed slightly better saline absorption and they had better vertical wicking and water retention time than pristine cotton gauze.  相似文献   

18.
Novel composite nanofibrous materials of poly(vinylidene fluoride) (PVDF) or poly(vinylidene fluoride-cohexafluoropropylene) (PVDF-HFP) and ZnO nanoparticles were prepared by conjunction of electrospinning and electrospraying techniques. Simultaneous electrospinning of concentrated solution of PVDF or PVDF-HFP and electrospraying of suspension of ZnO in diluted PVDF or PVDF-HFP solution enable the preparation of materials consisting of fibers on which ZnO was deposited on the fibers’ surface (design type “on”). These fibrous materials were compared with materials consisting of PVDF or PVDF-HFP fibers in which ZnO was incorporated in the fibers (design type “in”) and which were obtained by one-pot electrospinning of a suspension of ZnO nanoparticles in concentrated PVDF or PVDF-HFP solution. The fiber morphology and the presence of ZnO “in” or “on” the fibers were observed by scanning electron microscopy (SEM) and by transmission electron microscopy (TEM). The effect of the used technique on the type, size and shape of the obtained structures was discussed. The fibrous mats were studied by differential scanning calorimetry (DSC), thermogravimetric analysis (TGA), X-ray diffraction (XRD), contact angle measurements and mechanical tests as well. It was found that the decoration of fibers with ZnO resulted in increase of their thermal stability and hydrophobicity. The microbiological tests showed that the materials of design type “on” possessed strong antibacterial activity against the pathogenic microorganism Staphylococcus aureus. The results suggest that, due to their antibacterial activity, the obtained composite materials are suitable for wound dressing applications.  相似文献   

19.
The evolution during ripening of Beta vulgaris (var. Pablo) on colour and betalain composition, not previously conducted in conjunction in red beets, has been examined. According to the results, it could be asserted that the ripening stage significantly (p?<?0.05) influenced on all the studied parameters. On the basis of the betalain content, the optimum ripening stage corresponded to a medium weigh-to-calibre ratio, in the light of the significantly (p?<?0.05) higher content of betalains, especially betanin and vulgaxanthin I. Moreover, colour attributes also differed during ripening, having the medium-ripened beetroots a significantly (p?<?0.05) more reddish hue (hab) and lower lightness (L*), probably due to the higher content of betaxanthins in this stage. The colour differences among red beets in the stage II and the rest of stages were visually appreciable (ΔE*ab?>?3) and mainly qualitative. A new range of opportunities for diversification of colorant market, from a nutritional and colorimetric point of view, could be possible by employing red beets with different stages of ripening.  相似文献   

20.
The phenolic content/composition and antioxidant activity of hot/cold infusion and decoction from the leaves of Arbutus unedo were studied for the first time. 1,1-diphenyl-2-picrylhydrazyl (DPPH●), 2,2′-azino-bis(3-ethylbenzothiazoline-6-sulphonic acid) radical cation (ABTS●+), crocin-bleaching, copper-reducing, and liposome accelerated oxidation assays were used for the evaluation of the activity in vitro. In vivo, the extracts were examined for their ability to protect S. cerevisiae cells from H2O2 induced oxidative stress. An on-line high-performance liquid chromatography-DPPH● assay was applied to identify potent radical scavengers and comment on their contribution to the total activity. The addition of leaves to boiling water (decoction) was the most appropriate practice to apply since the highest phenol intake (220.2 mg gallic acid/cup served) was obtained. Additionally, its antioxidant activity was equal or superior to that of the other extracts. Flavonols (~51–61 mg/g dry extract) were the main phenols in all the extracts, with quercitrin accounting for ~20% of the total phenol amount. The on-line DPPH● method verified the high potency of the decoction and indicated as the most active radical scavengers, two galloylquinic acid derivatives and myricitrin, accounting for ~28–45% and ~11–13% of the total scavenging, respectively. Present data may contribute to the future exploitation of A. unedo leaves by the food industry for health-promoting herbal tea preparations and dietary supplements.  相似文献   

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