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1.
Our study proposes an enzymatic scouring method for cotton fabrics using the enzyme cutinase. We established cutinase treatment conditions for cotton fabrics from their relative activity at different pH levels, temperatures, enzyme concentrations, and treatment times. Weight loss, moisture regain, K/S value, tensile strength, and SEM micrographs of cotton fabrics were analyzed. We determined the optimum cutinase treatment conditions to be as follows: pH of 9.0, temperature of 50°C, cutinase concentration of 100 %, and a treatment duration time of 60 min. We discovered that this cutinase treatment hydrolyzed the cuticle of cotton fabrics. The cutinase treatment did not decrease the moisture regain and the K/S value. The optimum concentrations of Triton X-100 and calcium chloride, which were used as auxiliaries for cutinase treatment, were found to be 0.5 % (v/v) and 70 mM, respectively. Some cracks were observed on the surface of the cotton fibers; however, the tensile strength did not decrease.  相似文献   

2.
Surface modification of polyester fabrics by enzyme treatment   总被引:1,自引:0,他引:1  
In this study, the effect of enzymatic hydrolysis using lipase and cutinase on poly(ethyleneterephthalate) (PET) fabrics was investigated in an attempt to improve the hydrophilicity of these fabrics. The hydrolytic activity of the enzymes was expressed for variations in pH levels, temperatures, enzyme concentrations, and treatment times. The effects of using a nonionic surfactant were examined by measuring moisture regain and surface wettability. Finally, the fabric characteristics that were affected by enzyme treatment were evaluated by tensile strength and scanning electron microscopy. The optimal treatment conditions for lipase were determined to be a pH of 4.2, a temperature of 50 °C, a lipase concentration of 100 %, and a treatment time of 90 min; those for cutinase were determined to be a pH of 9.0, a temperature of 50 °C, a cutinase concentration of 100 %, and a treatment time of 60 min. At optimal enzymatic treatment conditions, we got the significant results of increase on the moisture regain and the water contact angle (WCA) and water absorbency effectively decreased. Triton X-100 facilitated cutinase hydrolysis on PET fabrics; however, it was ineffective for lipase. With enzymatic treatment, the tensile strength did not decrease.  相似文献   

3.
Seabuckthorn (Hippophae rhamnoides L.) is uniquely capable of growing well under various extreme environmental conditions, such as water deficit, salt stress, low temperature, and high altitude. It is of economic value and its berries are used in cosmetics and pharmaceutical products. In this study, we compared the effects of salt stresses (9:1 molar ratio of NaCl to Na2SO4, pH 6.48–6.65) and alkali stresses (9:1 molar ratio of NaHCO3 to Na2CO3, pH 8.70–8.88) on the levels of inorganic ions and organic acids in H. rhamnoides L. to elucidate the physiological mechanism by which it tolerates salt or alkali stress (high pH). The results showed that, in leaves and stems under alkali stress, the Na+ content increased to a much greater extent than under salt stress. Neither salt nor alkali stress decreased the K+ content in leaves and stems; however, in roots, the K+ content decreased sharply with increasing alkali stress, whereas it remained relatively unchanged with increasing salt stress. This revealed a specific mechanism of absorption or transport for Na+ and K+ that was affected strongly by alkali stress. The results indicated that accumulation of organic acid (OA) was a central adaptive mechanism by which H. rhamnoides maintained intracellular ionic balance under alkali stress. OA may play different roles in different organs during adaptation to alkali stress, and its percentage contribution to total negative charge was higher in leaf than in stem. H. rhamnoides accumulated mainly malate, oxalate, and citrate in leaves and stems; however, in roots, less malate and citrate was accumulated, and acetate accumulation was enhanced significantly, which indicated that roots and shoots use different mechanisms to modulate OA metabolism.  相似文献   

4.
Following our previous research [1], an extensive investigation on the effects of four mercerization treatment parameters namely, alkali concentration, time of treatment, bath temperature, and mercerization tension on dimensional properties of plain knitted fabric produced from cotton yarn is presented in this paper. Numerical values of constant geometry of the dry relaxed, wet relaxed, and mercerized samples were calculated according to Munden’s equations. Study shows that the area geometry constant values (K s ) achieved after mercerization treatment was higher than values obtained for the samples subjected to dry and wet relaxations. Also, ANOVA test confirmed significant effects of each parameter itself and their interactions on dimensional properties of the fabric samples. Based on the results, applying less value of tension improves dimensional stability of the fabric but not for the samples mercerized in higher values of three other parameters. The alkali concentration had an optimum value in mercerization treatment. In mercerizing conditions carried out in high temperature and long time, lower alkali concentration is more efficient. Increasing time of treatment leads to achieve higher K s value when lower value of alkali concentration is used. Most of the samples mercerized in bath temperature of 40 °C had the highest K s . At the end of the research a statistical model was derived to predict the area geometry constant of the fabric.  相似文献   

5.
More than 7000 red algae species have been classified. Although most of them are underused, they are a protein-rich marine resource. The hydrolysates of red algal proteins are good candidates for the inhibition of the angiotensin-I-converting enzyme (ACE). The ACE is one of the key factors for cardiovascular disease, and the inhibition of ACE activity is related to the prevention of high blood pressure. To better understand the relationship between the hydrolysates of red algal proteins and the inhibition of ACE activity, we attempted to identify novel ACE inhibitory peptides from Pyropia pseudolinearis. We prepared water soluble proteins (WSP) containing phycoerythrin, phycocyanin, allophycocyanin, and ribulose 1,5-bisphosphate carboxylase/oxygenase. In vitro analysis showed that the thermolysin hydrolysate of the WSP had high ACE inhibitory activity compared to that of WSP. We then identified 42 peptides in the hydrolysate by high-performance liquid chromatography and mass spectrometry. Among 42 peptides, 23 peptides were found in chloroplast proteins. We then synthesized the uncharacterized peptides ARY, YLR, and LRM and measured the ACE inhibitory activity. LRM showed a low IC50 value (0.15 μmol) compared to ARY and YLR (1.3 and 5.8 μmol). In silico analysis revealed that the LRM sequence was conserved in cpcA from Bangiales and Florideophyceae, indicating that the novel ACE inhibitory peptide LRM was highly conserved in red algae.  相似文献   

6.
《Crop Protection》1986,5(5):306-313
Antipenetrant action is the basis of disease control by non-fungitoxic concentrations of melanin biosynthesis inhibitors such as tricyclazole, pyroquilon and fhthalide. These compounds block the polyketide pathway, thus preventing melanization of the appressorial walls of Pyricularia oryzae and Colletotrichum species. Non-melanized appressorial walls of these pathogens do not appear to have the proper architecture and rigidity needed to penetrate plant epidermal walls. Moreover, polyketide metabolites which accumulate as a result of inhibition of melanin biosynthesis may interfere with the appressorial penetration processes in P. oryzae. Melanin biosynthesis inhibitors are important protectants used for the control of rice blast disease caused by P. oryzae. Cutinase inhibitors are another group of compounds which prevent infection at non-fungitoxic concentrations, apparently by specifically inhibiting cutinase activity. Antipenetrants in this group include diisopropylfluorophosphate and paraoxon. The organophosphate fungicides IBP (Kitazin) and edifenphos (Hinosan) are cutinase inhibitors and display a specific antipenetrant action, but in practice their disease control activity may also involve direct fungitoxicity. The fungicide benomyl degrades to the fungitoxic product carbendazim and butylisocyanate. Superior performance of benomyl as compared to that of carbendazim, which is sometimes observed in disease control, possibly results from the inhibition of cutinase by butylisocyanate. The antibiotic, validamycin A, does not inhibit production of mycelial mass by Rhizoctonia species but blocks hyphal extension and increases branching. This antibiotic may act as an antipenetrant toward Rhizoctonia-type fungi. The development of antipenetrant chemicals offers an interesting approach as a mechanism for control of plant fungal diseases.  相似文献   

7.
In the polycondensation reaction of polyethyleneterephthalate(PET), Sb2O3 can react effectively as a catalyst, if physically transformed. Sb2O3 powder is transformed into liquid solution by dissolving in ethylene glycol(EG). Homogeneous catalyst is made by mixing this liquid solution with glycols having different solubility. The efficient reaction of PET polymerization is expected by using homogeneous catalyst. PET was synthesized using homogeneous catalysts of 4 wt.% Sb2O3 solution dissolved in glycol[EG, 2,2-bis(4-(2-hydroxyethoxy)phenol)propane(BHPP), neopentyl glycol(NPG), and 1,3-propandiol(PD)]. PET using EG-BHPP(Sb2O3) catalysts shows the highest I.V. within a reaction time of 120 min. In the p-d analysis, PET using EG-BHPP(Sb2O3) catalysts has the fastest propagation rate and slowest degradation rate. EG-BHPP(Sb2O3) catalysts are more efficient than EG(Sb2O3) catalysts and Sb2O3 powder catalysts.  相似文献   

8.
The effect on the viscosity of wheat flour batter following treatments with a crude pentosanase-containing enzyme preparation and an endo-xylanase purified from the same preparation, was studied in relation to changes to the chemical features of the water- and Ba(OH)2-extractable arabinoxylan fractions. Addition to batter of the crude enzyme or the pure xylanase caused a consistent and identical decrease in batter viscosity, demonstrating that the viscosity change was caused by the selective action of the xylanase in the crude enzyme preparation. The lowering of batter viscosity upon addition of enzyme was attributed to partial hydrolysis of the arabinoxylans in the water-extractable fraction which lead to an increase in the proportion of lower molecular weight water-extractable arabinoxylans possessing an increased xylose/arabinose ratio. There was no detectable change in the monosaccharide composition of either the water- or Ba(OH)2-extractable arabinoxylan fraction after enzyme treatment and no indication of any increase in the amount of the water-extractable arabinoxylan fraction at the expense of the Ba(OH)2-extractable fraction. It is concluded that the xylanase can extensively degrade arabinoxylan to small oligosaccharides in vitro. However, such degradation does not take place in situ, in the enzyme treated batters, where only a very small shift in the molecular weight profile of the water-extractable arabinoxylans was necessary to effect major changes to batter viscosity.  相似文献   

9.
One step dyeing of polyethylene terephthalate (PET) fabrics combining pretreatment and dyeing under the alkali condition was developed for cleaner production. One step dyeing of PET fabrics required that the dye used has good acid and alkali stability. In this paper, dyeing properties of three azo disperse dyes containing cyano group based on benzisothiazole, 3- (4-N-ethoxyl-N-cyanoethyl -phenyldiazenyl)-5-nitro-2,1-benzisothiazole (D1), 3-(4-N-ethyl-N-cyanoethyl- phenyldiazenyl)- 5-nitro-2,1-benzisothiazole (D2), and 3-(N-benzyl-N-cyanoethyl- phenyldiazenyl)-5-nitro-2,1-benzisothiazole (D3), were investigated under alkali condition. The results showed that polyester fabrics could be well dyed with D1, D2 and D3 under the acid condition. However, D1 was decomposed while dyeing at the alkali solution. D2 and D3 had excellent color yields under the alkali condition. The acid-alkali stability and the structure change were analyzed by UV-vis spectrum and high pressure liquid chromatography (HPLC). Gaussian 09 program package was used to optimize geometry by B3LYP method and 6-31G (d) basis set. The solvation energy of D1 in water was higher than those of D2 and D3. The electron withdrawn effect of the hydroxyl affected the energy gap of HOMO and LUMO orbits. D2 and D3 showed excellent stability in the strong alkali medium. And the dyed polyester fabrics with D2 and D3 at the alkali condition also had good fastness properties.  相似文献   

10.
The present work emphasizes the effect of alkali (NaOH) solution on macromolecular parameters of sisal fiber. The macromolecular parameters of alkali treated sisal fiber were computed along with air-dried sisal fiber by treating fiber as a non-ideal two-phase system characterized by continuous variation of electron density at the phase boundary. Small angle Xray scattering (SAXS) technique was employed to evaluate the macromolecular parameters, using correlation functions, applying the theories of Vonk, Ruland and Misra et al. The finite value of width of transition layer suggests to treat the fiber to be a non-ideal two-phased system. The evaluated macromolecular parameters are: transversal periodicity, specific inner surface, volume fractions of matter and void phases, transversal lengths in both phases, range of inhomogeneity, volume fraction of transition layer and length of coherence.  相似文献   

11.
Aliphatic units (ethylene succinate) were incorporated into aromatic water-soluble polyesters (WSP) in order to improve their environmental protection and sizing performances. The environmental performance was measured in terms of biological oxygen demand for 5 days (BOD5) and chemical oxygen demand (COD). Apparent and intrinsic viscosities, the adhesion to polyester fibers, glass transition temperature, and mechanical behavior of sizing films of WSP were evaluated for improving their sizing performance. The composition of copolymeric WSP was also investigated by 1H-NMR. A series of copolymeric WSP with a variation in molar ratio of aliphatic monomer (dimethyl succinate) to aromatic monomer (dimethyl terephthalate) from 10:90 to 40:60 was synthesized through a two-step reaction, transesterification and polycondensation. It was found that, by incorporating aliphatic units into the macromolecular chain of aromatic WSP, the environmental performance, apparent and intrinsic viscosities, and the toughness of sizing film were enhanced obviously. The adhesion to polyester fibers showed no sensitivity to the molar ratio of dimethyl succinate to dimethyl terephthalate when the ratio ranged from 10:90 to 30:70. In view of overall performance of the aliphatic-containing WSP sizes, the molar ratio should be 30:70. Based on the ratio, the WSP prepared showed better environmental and sizing performances.  相似文献   

12.
PET fabric was first modified with silane coupling agent KH-560, and then was loaded with a layer of nano-scaled TiO2 particles using tetrabutyl titanate as precursor by low temperature hydrothermal method, followed by dyeing with Disperse Blue 56. The morphology, crystalline phase, chemical modification, thermal stability and optical property of PET fiber before and after treatments were studied by scanning electron microscope, X-ray diffraction, X-ray photoelectron spectroscopy, thermal gravimetric and diffuse reflectance spectrum techniques. The properties of tensile, air permeability, luster, ultraviolet (UV) protection, photocatalytic activity, K/S value and color fastness were also measured. It was found that compared with the TiO2-coated fabric without modification with KH-560, the loading of TiO2 nanoparticles on the surface of the TiO2-coated fabric modified with KH-560 was obviously improved. The pure anatase TiO2 nanoparticle was grafted onto the fiber surface. The onset decomposition temperature increased. The absorbing capability to ultraviolet radiation was enhanced. The properties of tensile, air permeability, luster, K/S value and color fastness changed slightly. The UV protection ability and photodegradation of methyl orange under UV illumination were enhanced to some extent.  相似文献   

13.
In the presence of Pt catalyst, α,ω-hydrogenpolysiloxane reacted with allyl glycidyl ether, and an intermediate α,ω-diepoxysiloxane was formed. The epoxy cyclic-opening reaction was conducted between the intermediate and polyetheramine in isopropanol solution, the silicone polyetheramine block copolymer (BPEAS) was thus made. The chemical structures of BPEAS were characterized using IR and 1H-NMR separately. Then cotton fabric was treated with BPEAS for application purpose. The finishing effects were tested in terms of film morphology, hydrophilic ability, softness and mechanical properties. The recorded results showed that BPEAS can be used directly to treat cotton fabrics without adding any emulsifier at the viscosity of 6700 mPa·s and amino value of 0.6009 mmol/g. Bending rigidity and hysteresis of the treated fabric decreased by 53.53 % and 67.39 %, the drape coefficient dropped by 15 %, whereas the wrinkle recovery angle increased by 57.14 %. The treated cotton fabric is hydrophilic, and has a bulky soft hand, better anti-wrinkle property compared to the untreated one.  相似文献   

14.
Acrylonitrile-methyl itaconate (AN-MIA) copolymers were successfully prepared by free-radical solution copolymerization, and then were spun into precursors of carbon fibers by one-step wet-spun method in this study. Effect of methyl itaconate(MIA), itaconic acid (IA) and methyl acrylate (MA) on the characteristics of the copolymers and precursors were studied in contrast. The monomer reactivity ratios for AN/MIA system were determined by Kelen-Tudos (K-T) method with r 1=0.65, r 2=1.80. The viscosity test shows that using MIA as a co-monomer is an effective way to decrease the viscosity of PAN solution. During the spinning and stretching processes, polyacrylonitrile (PAN) copolymer with MIA as co-monomer can reach the higher total draw-ratio of 12.0 folds, while PAN copolymer with IA as co-monomer can reach only 8.5 folds. The fineness and elongation at-break of the PAN precursors with MIA as co-monomer improve, but the tenacity decreases. DSC test shows MIA is less effective in improving the thermal property than IA.  相似文献   

15.
为研究基因型与环境对小麦戊聚糖含量及RVA黏度的影响,选取10个小麦品种(系)和5个生态试验点,测定了小麦籽粒中的总戊聚糖(TP)、水溶性戊聚糖(WSP)、非水溶性戊聚糖含量(WIP)和RVA黏度等共10个性状,探讨了3种戊聚糖含量和7个RVA性状的影响因素及相互关系。结果表明,包括总戊聚糖、水溶性戊聚糖含量在内的10个性状均受到基因型、环境以及基因型与环境互作的影响。其中,基因型方差和环境方差在所有性状上均达到显著或极显著,基因型与环境互作方差在水溶性戊聚糖和7个RVA性状上达到极显著;戊聚糖含量的环境变异>基因型变异>基因型与环境互作变异,而RVA黏度性状的基因型变异均大于环境变异。水溶性戊聚糖含量与高峰黏度呈显著负相关。  相似文献   

16.
3,3'-[1,2-ethanediylbis (oxy-2,1-ethanediyl)]-bis[1-methyl-imidazolium]-dibromide (DImDBr), a gemini imidazolium ionic liquid, was synthesized for the modification and dyeing promotion of poly(ethylene terephthalate) (PET) filaments. The results showed that parameters such as treatment temperature, time, and DImDBr concentration played a critical role on the tensile strength and tensile strength retention of modified PET filaments. The optimal treatment parameters of the PET filaments were 120 °C for 90 min with addition of 6 % ionic liquid. The influence of disperse dyeing parameters (temperature, time, and dye concentration) on DImDBr modified PET filaments were also studied. The disperse dyed PET filaments (after treatment with DImDBr) exhibited a desirable color strength (K/S value), excellent soap washing fastness, light fastness, and rubbing fastness. Furthermore, the native PET filaments and DImDBr treated PET filaments were characterized by FT-IR, XRD, DSC, TGA, and SEM. Density functional theory (DFT) simulation showed the presence of two kinds of hydrogen bonds (C-H/O and O-H/Br) and eight strong hydrogen bonds in the DImDBr/cis-PET monomers, while only three hydrogen bonds were found in the DImDBr/trans-PET monomers. The structural transformation from the crystalline phase to the amorphous phase (FT-IR, XRD, and DFT simulation) after DImDBr modification confirmed the dyeing promotion of PET filaments at lower temperature.  相似文献   

17.
Poly(ethylene terephthalate) (PET) fibers were grafted with glycidyl methacrylate (GMA) using benzoyl peroxide as initiator. 1,6-diaminohexane (HMDA) was then covalently attached to this GMA grafted PET fibers. Variations of time, temperature, initiator and monomer concentrations were investigated. HMDA-GMA-g-PET fibers were used as a new sorbent for removal of Cr(VI) ions from aqueous solutions through batch adsorption method. Effects of various parameters such as pH, treatment time, and initial ions concentration on the adsorption amount of ions onto reactive fibers were investigated. The adsorption rates of Cr(VI) ions were much higher on the HMDA-GMA-g-PET fiber than on GMA-g-PET and ungrafted PET fiber. Within 60 min, at pH 3, Cr(VI) was removed by 98 % while the initial concentration of ions was at 25 mg/l and by 94 % at 400 mg/l. The Cr(VI) ions adsorbed were easily desorbed by treating with 1M KOH within 10 min.  相似文献   

18.
The objectives of this study were to determine the effects of genotype on chemical components of barley which influence nutritional value. Six barley (Hordeum vulgareL.) isotypes, expressed in Compana (CI 5438) and Betzes (CI 6398) cultivars with genetic combinations non-waxy (WXWX) and waxy (wxwx) starch in covered (NN) and hulless (nn) kernels and long-awn (LK2LK2) and short-awn (lk2lk2) traits, were grown in 1987, 1988 and 1989. Analyses were made for protein, fat, starch, free sugars, total dietary fibre (TDF ), TDF components and extract viscosity. The hulless gene reduced TDF by preventing the hulls from adhering to the kernel, thus concentrating the remaining components. Waxy barleys contained less (P<0·001) starch, but more (P<0·001) free sugars and ether extract (P<0·001). Increased (P<0·02) TDF in waxy barleys was due to an increase (P<0·001) in total and soluble β-glucans. The short-awn gene had no effect other than to increase (P<0·04) extract viscosity, and to reduce test weight (P<0·008) and % plump kernels (P<0·03). The expression of the hulless and waxy genes in barley is desirable for use in human food products due to increased levels of soluble dietary fibre, particularly β-glucans, but reduces malting potential and feed value for poultry.  相似文献   

19.
Peach brown rot is a severe disease caused by ascomycete fungus Monilinia fructicola and is primarily controlled by chemical fungicides. However, the utilization of fungicides has caused many problems such as microbial resistance, environmental pollution, and fruit contamination. The growing concern for food safety requires alternative management methods that are safe to humans and benign to the environment. Here we report that the extract from Coptis chinensis (a Chinese herb named “Huang Lian”) demonstrates a strong inhibition to M. fructicola. The 50% effective concentration (EC50) of C. chinensis extract to M. fructicola was only 0.91 mg/mL, while the EC50s to other fungi such as Botrytis cinerea and Alternaria solani were 14.09 mg/mL and 27.35 mg/mL, respectively. These results indicate that the extract of C. chinensis has a specific inhibition to M. fructicola. Subsequent partitioning of the ingredients in C. chinensis extract revealed that berberine, the conventional anti-bacterial alkaloid, was the predominant ingredient that exerted robust inhibition against M. fructicola. The EC50 and minimum inhibitory concentration (MIC) against M. fructicola were as low as 4.5 μg/mL and 46.9 μg/mL, respectively. Compared to berberine’s analogs in C. chinensis such as palmatine, berberine tannate and jatrorrhizine, berberine showed the strongest inhibition against M. fructicola. This finding provided insight into the structure–activity relationship between berberine and its analogs. Notably, not only can berberine prevent spore germination and hyphal growth, it also inhibits the activity of cutinase secreted by M. fructicola, implying the potential function of berberine in reducing the pathogenesis of M. fructicola. In addition, the strong in vivo inhibition of berberine against M. fructicola was observed with no visual cytotoxicity noted to peach fruits, even at berberine concentration of 400 μg/mL. Note that this was much higher than its MIC value (46.90 μg/mL). Overall berberine, as a natural compound, may be a promising candidate in control of brown rot.  相似文献   

20.
The stress relaxation behaviour of barley kernels with differences in β-glucan was studied using the generalized Maxwell model for explaining the differences in quality. The relaxation moduli show that cultivar significantly affected the relaxation times (τ2 and τ3) and compressional viscosity (ηE2 and ηE3) of the 3 Maxwell elements and the pure elastic component (E0). These data were twice as high in cultivars with high β-glucans compared to low β-glucans. Protein and malt extract, as well as β-glucan, showed similar patterns to the corresponding cultivars from the same locations. Malt extract was correlated with both insoluble fibre (−0.71; P < 0.0007) and total fibre (−0.66; P < 0.006). High β-glucan cultivars presented relatively high soluble fibre, wort viscosity and presented higher relaxation times. Soluble fibre and the wort viscosity were correlated with relaxation times τ1, τ2, τ3. Also, β-glucans were correlated with τ3 and viscosity ηE3. The overall importance of the effect of β-glucans on viscoelasticity, malting and food quality as shown in this investigation is in agreement with earlier investigations.  相似文献   

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