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1.
In the present paper, we analyze a seed fiber arising from Pergularia tomentosa L. (PTL). It was, primarily, characterized using different techniques. The morphology of the fibers was observed via Scanning Electron Microscopy (SEM). They are also checked in term of decomposition behavior through TGA/DTG instrument. The cristallinity index was determined using XRD and it was about 52 %. The chemical composition in terms of moisture percent, ash, waxes and fats, lignin, hemicellulose and cellulose were, respectively 8.5 %, 2.74 %, 1.88 %, 8.6 %, 16 % and 43.8 %. The contact angle value was measured and the evolution of drop profile was captured with video-camera using GBX Tensiometer Surfaces Sciences Studies. Further, fibers were dyed with Methylene Blue, Direct Red 79, Sumifix supra yellow 3RF and Reactive Blue 198. Color coordinates (ΔL*, Δa*, Δb*, ΔC* and ΔH*) of the samples were so measured. All obtained data were compared to cotton fibers and some other cellulosic fibers. The Results revealed that, based on such properties, PTLF could be a competitive fiber in many applications field (textile weaving, composites, etc).  相似文献   

2.
Upon UV irradiation wool fabrics can be photografted with photoactive acrylamido dyes at room temperature without photoinitiaors, which is eco-friendly coloration process compared with conventional adsorption-based dyeing. Acrylamide addition as a comonomer can improve the photografting probably by reducing the steric hindrance between the bulky dyes during the photocopolymerization. Even without photointiators and neutral salts, the optimal K/S values of the photografted wool reached upto 18.7 and 18.5 for Reactive Red 84 and Yellow 39 dyes respectively. The optimal UV-grafting coloration can be achieved when a UV energy of 25 J/cm2 was irradiated on the padded fabrics with 6.3 %owf dye containing 0.65 mole ratio of acrylamide to the dyes. Furthermore, the color fastness of the grafted fabrics was as good as those of conventionally dyed fabrics due to the copolymerization of dyes and comonomers.  相似文献   

3.
A series of new azomethine dyes based on pyrazolone system have been synthesized via different routes. The solvatochromism for the dyes was evaluated with respect to spectroscopic properties in various solvents. The dyes were applied as disperse dyes on polyester fabrics and gave shade poor to excellent light fastness, washing, perspiration, sublimation, and rubbing fastness properties. Also the position of color in CIELAB coordinates (L*, a*, b*) and K/S value were investigated.  相似文献   

4.
The present study has been focused on the extraction of natural dyes from Syzygium cumini (L.) Jambolan fruit dry seed endosperm and investigation of their phytochemicals and pharmacological characteristics. Dyes were prepared using aqueous, acidic, alcoholic and alkaline extraction techniques. UV spectral studies of the dyes showed a variation in absorption maxima and their color varied with respect to the pH and the solvent used during extraction. The dye was prepared from Jambolan fruit dry seed endosperm showed good antibacterial activity. The aqueous extraction of Jambolan fruit dry seed endosperm was able to inhibit the growth of many bacterial strains viz S. lutea, E.coli, P. aeruginosa, Pseudomonas fluorescens and S. aureus etc. The antimicrobial property of the dyes was used in developing antimicrobial fabric.  相似文献   

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.

Background

The gypsovag shrub Cistus clusii is locally dominant in semi-arid gypsum plant communities of North-Eastern Spain. This species commonly grows in species-poor patches even though it has nurse potential, suggesting interference on neighbouring species. Other Cistus species exert a chemically mediated interference on plant communities, suggesting that it might be a common phenomenon in this genus. This study aimed investigating whether C. clusii exerts chemically mediated interference on neighbouring species in gypsum plant communities. We tested in a greenhouse whether aqueous extracts from C. clusii leaves (L), roots (R) and a mixture of both (RL) affected germination, seedling survival, and growth of nine native species of gypsum communities, including C. clusii itself. We further assessed in the field richness and abundance of plants under the canopy of C. clusii compared to Gypsophila struthium (shrub with a similar architecture having a nurse role) and in open patches. Finally, we specifically assessed in the field the influence of C. clusii on the presence of the species tested in the greenhouse experiment.

Results

Aqueous extracts from C. clusii (R and RL) negatively affected either germination or survival in four of nine species. In the field, richness and abundance of plants were lower under the canopy of C. clusii than under G. struthium, but higher than in open patches. Specifically, five of nine species were less frequent than expected under the canopy of C. clusii.

Conclusions

Cistus clusii shows species-specific interference with neighbouring species in the community, which may be at least partially attributable to its phytotoxic activity. To our knowledge, this is the first report of species-specific interference by C. clusii.
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7.
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   

8.
9.
Fusarium semitectum is one of the important causal agents of dry rot of potato tubers in the world. In order to determine genetic variability among 41 isolates of F. semitectum, morphological and molecular studies were carried out. All F. semitectum isolates were recovered from infected potato tubers with dry rot symptoms collected from four provinces in Iran. According to macroscopic and microscopic characteristics, 41 isolates of F. semitectum were classified in two morphotypes (morphotypes I and II). All 41 isolates were evaluated for their pathogenicity on healthy potato tubers. Tuber rot symptoms were observed on the 21st day after inoculation of Fusarium isolates on the tubers tested. The measurement was done by comparing the depth and width of lesion expansion among the isolates. Molecular characterization through PCR-IGS-RFLP analysis by six restriction enzymes (AluI, BsuRI, Eco88I, MspI, TaqI and PstI) divided the 41 isolates of F. semitectum into two separated clusters that were in accordance with the morphological characterization.  相似文献   

10.
The use of natural dyes and natural finishes on textiles has become a matter of significant importance because of the increased environmental awareness to avoid some hazardous synthetic dyes and synthetic chemicals. The Delonix regia stem shells were extracted in distilled water methanol and ethanol solvents. Phytochemical analysis was carried out for the presence of bioactive chemical constituents such as saponin, terpenoid, flavonoid, glycoside, phenol and tannin using the standard procedure. All the tests showed positive for the presence of components except saponin in methanol and ethanol extract. The qualitative antibacterial analysis was done by AATCC 147 method with excerpts from three different solvents both against S. aureus (gram-positive) and E. coli (gram-negative) bacteria. Delonix regia stem shell extract (DSE) in distil water was used for natural dyeing of mulberry silk fabric. Pre-mordanting and post-mordanting of silk fabric were carried out using alum and myrobalan mordants. Treated fabrics showed a substantial increase in colour depth (K/S) and adequate wash, light and rubbing fastness properties without and with mordanted and dyed silk fabrics. Quantitative antibacterial analysis by AATCC 100 method was done on dyed silk fabric which showed very good resistance both against bacteria S. aureus and E. coli bacteria. Dyed silk fabric also showed good to very good ultraviolet (UV) protection property. The physicochemical composition of the untreated and without mordant treated silk fabrics were analysed by attenuated total reflection (ATR) Fourier transforms infrared (FTIR) spectroscopy, scanning electron microscope (SEM), energy dispersive spectrometry (EDS) and atomic absorption spectrophotometer (AAS). In addition to that wash, durability was also measured of dyed silk fabric for antibacterial and ultraviolet protection (UPF) properties according to AATCC 61 2A washing method.  相似文献   

11.

Background

The drivers of species co-existence in local communities are especially enigmatic for assemblages of morphologically cryptic species. Here we characterize the colonization dynamics and abundance of nine species of Caenorhabditis nematodes in neotropical French Guiana, the most speciose known assemblage of this genus, with resource use overlap and notoriously similar external morphology despite deep genomic divergence.

Methods

To characterize the dynamics and specificity of colonization and exploitation of ephemeral resource patches, we conducted manipulative field experiments and the largest sampling effort to date for Caenorhabditis outside of Europe. This effort provides the first in-depth quantitative analysis of substrate specificity for Caenorhabditis in natural, unperturbed habitats.

Results

We amassed a total of 626 strain isolates from nine species of Caenorhabditis among 2865 substrate samples. With the two new species described here (C. astrocarya and C. dolens), we estimate that our sampling procedures will discover few additional species of these microbivorous animals in this tropical rainforest system. We demonstrate experimentally that the two most prevalent species (C. nouraguensis and C. tropicalis) rapidly colonize fresh resource patches, whereas at least one rarer species shows specialist micro-habitat fidelity.

Conclusion

Despite the potential to colonize rapidly, these ephemeral patchy resources of rotting fruits and flowers are likely to often remain uncolonized by Caenorhabditis prior to their complete decay, implying dispersal-limited resource exploitation. We hypothesize that a combination of rapid colonization, high ephemerality of resource patches, and species heterogeneity in degree of specialization on micro-habitats and life histories enables a dynamic co-existence of so many morphologically cryptic species of Caenorhabditis.
  相似文献   

12.
Reactive dyes are used widely in cotton dyeing process. Reactive dyeing uses high amounts of inorganic salts to accelerate dye exhaustion. These salts are then discharged to the effluent, leading to serious environmental problems. Biodegradable organic salts can alternatively be used in the dyeing process. In this paper, a new liquid organic salt was synthesized by acid-base neutralization, which was used to replace inorganic salts in reactive dyeing. Dye exhaustion in organic salt dyeing was similar to the values in conventional dyeing. However, dye fixations were slightly lower in organic salt dyeing than in conventional dyeing. The washing fastness of dyed fabrics with organic salt was excellent. Experimental results showed that dye exhaustion reached the maximum value when the concentration range of organic salt was from 20 g/l to 40 g/l. In addition, the optimal alkali concentration in organic salt dyeing was found to be about 30 g/l. These parameters suggested organic salt could replace inorganic salt in reactive dyeing process.  相似文献   

13.
PLA/PLA-g-ABS blends were prepared and evaluated for mechanical properties performance. Firstly, carboxylic acid functionalized ABS particles were synthesized by grafting polymethacrylic acid (PMAA) onto ABS particle surface using potassium persulfate as an initiator. The reaction was followed by FTIR analysis. The resultant carboxylated ABS was melt mixed with virgin PLA in an internal mixer to obtain PLA/PLA-g-ABS blends. The obtained PLA/PLA-g-ABS blends were subject to injection molding to obtain specimens for testing evaluation. It was found that impact resistance values significantly outperformed neat PLA by 60 %, 87 %, and 150 % for PLA/PLA-g-ABS 10 wt%, PLA/PLA-g-ABS 20 wt%, and PLA/PLA-g-ABS 30 wt%, respectively. A significant increase in impact strength was contributable to ABS rubber which exhibited even dispersion and good interfacial adhesion. The impact strength was dependent on the percent loading of PLAg-ABS; the more the PLA/PLA-g-ABS the higher the impact strength value. In a similar manner, tensile strength increases when loaded with PLA/PLA-g-ABS albeit at lesser effect. Considering the percent elongation, a massive increase in percent elongation was recorded in case of PLA/PLA-g-ABS 20 wt% and PLA/PLA-g-ABS 30 wt%, implying that these blends were extremely flexible and tough when compared to neat PLA, control, and PLA/PLA-g-ABS 10 wt%.  相似文献   

14.
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   

15.

Background

The rice blast resistance gene Pi54 was cloned from Oryza sativa ssp. indica cv. Tetep, which conferred broad-spectrum resistance against Magnaporthe oryzae. Pi54 allelic variants have been identified in not only domesticates but also wild rice species, but the majority of japonica and some indica cultivars lost the function.

Results

We here found that Pi54 (Os11g0639100) and its homolog Os11g0640600 (named as #11) were closely located on a 25 kbp region in japonica cv. Sasanishiki compared to a 99 kbp region in japonica cv. Nipponbare. Sasanishiki lost at least six genes containing one other R-gene cluster (Os11g0639600, Os11g0640000, and Os11g0640300). Eight AA-genome species including five wild rice species were classified into either Nipponbare or Sasanishiki type. The BB-genome wild rice species O. punctata was Sasanishiki type. The FF-genome wild rice species O. brachyantha (the basal lineage of Oryza) was neither, because Pi54 was absent and the orientation of the R-gene cluster was reversed in comparison with Nipponbare-type species. The phylogenetic analysis showed that #11gene of O. brachyantha was on the root of both Pi54 and #11 alleles. All Nipponbare-type Pi54 alleles were specifically disrupted by 143 and 37/44?bp insertions compared to Tetep and Sasanishiki type. In addition, Pi54 of japonica cv. Sasanishiki lost nucleotide-binding site and leucine-rich repeat (NBS–LRR) domains owing to additional mutations.

Conclusions

These results suggest that Pi54 might be derived from a tandem duplication of the ancestor #11 gene in progenitor FF-genome species. Two divergent structures of Pi54 locus caused by a mobile unit containing the nearby R-gene cluster could be developed before domestication. This study provides a potential genetic resource of rice breeding for blast resistance in modern cultivars sustainability.
  相似文献   

16.
Air temperature (Ta) is commonly used for modeling rice phenology. However, since the growing point of rice is under water during the vegetative and the early part of the reproductive period, water temperature (Tw) is likely to have a greater influence on crop developmental rates than Ta during this period. To test this hypothesis, we monitored Tw, Ta, and crop phenology in three commercial irrigated rice fields in California, USA. Sampling locations were set up on along a transect from the water inlet into the field. (Water warms up as it moves into the field.) Ta averaged 22.7 °C across sampling locations within each field, but average seasonal Tw increased from 22 °C near the inlet to 23.4 °C furthest away from the inlet. Relative to Tw furthest from the inlet, low Tw near the inlet delayed time to panicle initiation (PI 5 days) and heading (HD 8 days) and the appearance of one yellow hull on the main stem panicle (R7 9 days). Using Tw instead of Ta when the active growing point is under water until booting (midway between PI and HD) in a thermal time model improved accuracy (root-mean-square error, RMSE) for predicting time to PI by 2.5 days and HD by 1.6 days and R7 by 1.8 days. This model was further validated under more typical field conditions (i.e., not close to cold water inlets) in six locations in California. Under these conditions, average Tw was 2.6 °C higher than Ta between planting and booting, primarily due to higher daily maximum Tw values. Using Tw in the model until booting improved RMSE by 1.2 days in predicting time to HD. Using Tw instead of Ta during this period could improve the accuracy of rice phenology models.  相似文献   

17.
18.
Phthorimaea operculella (Zeller) is one of the most common insect pests of cultivated potato in tropical and subtropical regions. In this research, a potential strategy to improve the insecticidal activity of plant essential oils for the effective management of P. operculella was studied. The insecticidal and residual effects of nanofiber oil (NFO) and pure essential oil (PEO) of Cinnamomum zeylanicum were assessed on PTM under laboratory conditions. The nanofibers were made by the electrospinning method using polyvinyl alcohol (PVA) polymer. The morphological characteristics of the nanofibers were evaluated by scanning electron microscopy and Fourier transform infrared spectroscopy. The chemical constituents of cinnamon essential oil (EO) were detected by GC/MS. Fumigant toxicity of NFO and PEO were evaluated on different growth stages (egg, male and female adults) of P. operculella. SEM and FTIR analyses confirmed the presence of EO on the nanofiber structure. The yield of the EO from C. zelanicum on the nanofibers was 1.86%. GC/MS analysis showed that cinnamaldehyde was the primary constituent (69.88%) of cinnamon EO. LC50 values of C. zelanicum EO and NFO were 4.92 and 1.76 μl/l air for eggs, 0.444 and 0.212 μl/l air for female adults, and 0.424 and 0.192 μl/l air for male adults, respectively. Fumigant bioassays revealed that NFO was more toxic than C. zeylanicum oil against at all stages of P. operculella. The residual effect of PEO and NFO was evaluated against the egg stage of the P. operculella. NFO lost insecticidal effectiveness 47 days after application, while the efficacy of PEO decreased 15 days after application. Our results suggest that NFO of C. zeylanicum can be used as an effective new tool for the management of P. operculella.  相似文献   

19.
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   

20.
In food industry, roselle beverages and their subproducts could be functional ingredients since they are an excellent source of bioactive compounds with improved performance due to their important anthocyanins content. The aim of this study was to analyze anthocyanin content and antioxidant properties of aqueous infusions elaborated with color contrasting Hibiscus materials and design a mathematical model in order to predict color-composition relationship. Color measurements of beverages from roselle (Negra, Sudan and Rosa) were made by transmission spectrophotometry, anthocyanins quantification was determined by HPLC, and antioxidant potential was evaluated by in vitro methods (ABTS and FRAP assays). Beverages prepared with particle size minor of 250 μm presented until 4- and 2- times more anthocyanins content and antioxidant capacity respectively, in comparison to beverages prepared with powders with particle size major of 750 μm. Positive correlations among pigments composition and color parameters were found (p?<?0.05), showing that anthocyanins content, antioxidant capacity, C*ab and hab values increased in relation with the smallest particle size of flours. Also, mathematical models were stablished to predict anthocyanin content (r?≥?0.97) and antioxidant capacity (r?≥?0.89) from color data; we propose equations for quick estimation of the antioxidant capacity in the Hibiscus beverages with high anthocyanin content. The obtained models could be an important tool to be used in food industry for pigment characterization or functional compounds with potential health benefits.  相似文献   

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