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71.
İsmail Hamad Özlem Erol-Dayi Murat Pekmez Evren Önay-Uçar Nazlı Arda 《Plant foods for human nutrition (Dordrecht, Netherlands)》2010,65(1):44-49
The objectives of this study were to examine the free radical scavenging activity and the protective effects against macromolecular
oxidation as well as the cytotoxic activity of Aphanes arvensis aqueous and methanolic extracts. Free radical scavenging activity was determined by DPPH method. The methanolic extract showed
a scavenging activity nearly equivalent to Trolox and Vitamin C and has an IC50 value of 4.54 μg/mL. Total antioxidant capacity was determined by CUPRAC method. The antioxidant capacity of aqueous and
methanolic extract was 0.792 and 1.550 mmol TE/g DWE, respectively. The protective effect of A. arvensis extracts against lipid peroxidation was evaluated using a liposome oxidation system. The methanolic extract was more active
than the aqueous extract. The aqueous extract possessed protective effect against protein oxidation in a dose dependent manner.
Both extracts showed inhibitory effect on DNA oxidation as measured by plasmid relaxation assay. Results presented here indicate
that A. arvensis possess strong antioxidant activity and protective effects with very little cytotoxic effect, and they can therefore be used
as a natural additive in food, cosmetic and pharmaceutical industries. 相似文献
72.
Isabel Egea Paloma Sánchez-Bel Felix Romojaro Maria Teresa Pretel 《Plant foods for human nutrition (Dordrecht, Netherlands)》2010,65(2):121-129
Total antioxidant activity of six non-cultivated but traditionally collected fruits from the south of Europe was assessed
by measuring their ability to reduce the hydroxyl radical ( OH· ) \left( {{\hbox{O}}{{\hbox{H}}^\bullet }} \right) and hydrogen peroxide (H2O2), and their Trolox equivalent antioxidant capacity (TEAC). This antioxidant activity was compared with that shown by the
synthetic antioxidants BHA (E-320), BHT (E-321) and propyl gallate (E-310). Total phenolics, ascorbic acid and the carotenoid
content of the fruits were also analyzed. All fruits showed a high ability to scavenge the OH· {\hbox{O}}{{\hbox{H}}^\bullet } radical, ranging from 60.61% to 81.04% inhibition for Rosa canina and Crataegus monogyna, respectively. The H2O2 scavenging capacity and the TEAC value varied widely, ranging between 3.63% and 87.26% inhibition of H2O2 and between 0.47 and 416.64 mM trolox g−1 FW for Sorbus domestica and Rosa canina, respectively. The antioxidant activity of fruits was higher than that of the synthetic additives analyzed, except in the
TEAC assay. The phenolic and carotenoid content of R. canina was much higher than that of the other fruits analyzed and its ascorbic acid concentration was also high, reflecting its
higher efficacy towards ABTS ·- {\hbox{ABT}}{{\hbox{S}}^{ \bullet - }} (TEAC assay) and H2O2 species. In spite of these associations, the correlation coefficients between total antioxidant activity and the antioxidant compounds
analyzed were not very significant; only phenolics and carotenoids showed a marginal correlation with the TEAC assay. The
results support the possible use of R. canina as natural antioxidant to replace the synthetic additives, as well as their use in the production of functional foods with
a high antioxidant activity. 相似文献
73.
Indigenous non-refrigerated methods like heaps and pits are used in India for short-term storage of potatoes (Solanum tuberosum L.) to avoid distress sale. Storing untreated potatoes generally results in high losses from sprouting, moisture loss and
rotting. To reduce storage losses by inhibition of sprouting and to determine the suitability of stored potatoes for processing
into crisps, a single spray application of a commercial formulation of 3-chlorophenyl carbamate (CIPC or chlorpropham) 50%
a.i., (Oorja, United Phosphorus Limited, Mumbai, India) of CIPC (or chlorpropham) was tested on potatoes during storage from
March to June under two traditional storage methods [heap (17–33 °C, 58–92% relative humidity (RH)) and pit (17–27 °C, 72–95%
RH)] in 2 years [2005 up to 90 days of storage (DOS) and 2006 up to 105 DOS], using four cultivars and two rates of CIPC application
(20 and 30 mg a.i. kg−1 tubers). The two rates of application were comparably effective in reducing weight losses, sprouting and sprout growth in
stored tubers, and the effect was more pronounced in pit storage than in heap storage. By contrast to untreated tubers, CIPC-treated
potatoes remained turgid under the two storage methods and fetched market prices comparable to those for cold-stored (2–4
°C) potatoes after 105 days of storage. Reducing sugar concentrations in treated potatoes decreased during storage especially
in 2006 when the initial reducing sugar concentration was higher than in 2005. Crisp colour improved only in 2005 after 90
DOS, but it deteriorated in 2006 during storage up to 105 DOS. Sucrose concentration increased tremendously during storage
in 2 years. Only one cultivar (Kufri Chipsona-1) with low initial reducing sugar concentration and less sucrose accumulation
during storage could produce acceptable colour crisps after storage in both years. The remaining three cultivars—with high
initial reducing sugar concentration—were suitable for processing after storage in heap and pit in 2005, but not in 2006.
Stored potatoes were safe for human consumption as the CIPC residue concentrations were far below the permissible level of
10 mg kg−1 as prescribed by the European Union. Single spray application of CIPC (20 mg kg−1 treatment) can effectively reduce storage losses in potatoes stored in traditional non-refrigerated methods of heap and pit
and extend the storage life by 90 to 105 days. 相似文献
74.
Mana Mashkour Yahya Maghsoudlou Mahdi Kashaninejad Mehran Aalami 《Potato Research》2018,61(4):375-389
In this study, the effect of a vacuum impregnation (VI) process with pulsed electric field (PEF) pretreatment on fortification of whole potato with ferric pyrophosphate was investigated. The VI process and PEF pretreatment were optimized with respect to physicochemical attributes of PEF-VI-processed samples using response surface methodology (RSM). The results indicated that the iron content of VI-processed and PEF-VI-processed potatoes was increased about 126 and 457%, respectively, compared to unprocessed potatoes. A more intensive PEF pretreatment led to a higher cell disintegration, decrease in colour and textural parameters and also increase in components leakage from treated potato. Our study suggests that whole 180-g potatoes should be pretreated at 394 V/cm with 36 pulses and then treated at 3.5 kPa for 37 min in vacuum stage and 39 min restoration time in atmospheric stage to achieve the highest iron fortification and the lowest physicochemical changes during PEF-VI processing. 相似文献
75.
There has been growing interest in the use of bioresource waste for natural dyeing and finishing. This paper discusses dye extraction from the novel source fruit shell waste of Sterculia foetida and its application on mulberry silk fabric to confer aesthetic coloration and wellness properties such as ultra-violet (UV) protection and antibacterial properties. Treated fabrics showed a substantial increase in color depth and adequate wash, light, and rubbing fastness properties for dyed silk fabrics with and without mordanting. Pre-and post-mordanting of silk fabrics were carried out using mordants such as alum, harda (myrobalan), and copper sulfate. UV-visible spectrophotometric analysis of fruit shell extract (FSE) at different pHs and FSE with three different mordants at neutral pH was used to understand the phenomena of dye-fiber interaction. The treated fabrics characterised by ATR-FTIR, SEM-EDS, and XRD analysis indicate the nature of dye fiber interaction justifying the multifunctional properties. The treated fabric also showed very good ultraviolet protection property and antibacterial properties both against S. aureus and E. coli bacteria even after ten washes. The results indicate that Sterculia foetida fruit shell extract offers an excellent potential as coloration, antibacterial, and ultraviolet protective agent for mulberry silk fabric. 相似文献
76.
Chromophore incorporated into the protein chains through residue modification on silk fibroin will be an important way to get new dyeing technology with improved color fastness. Herein, 1-aminoanthraquinone diazonium salt was prepared and used for the modified dyeing on tyrosine of silk fibroin. The silk after modified dyeing was measured by UV-Vis, FTIR, MS, 1H-NMR, Data color, and other testing techniques. Interestingly, the resulting silk showed excellent rub and wash fastness. The enhanced color fastness is contributed by an electrophilic substitution reaction between 1- aminoanthraquinone diazonium salt and the ortho position of phenolic hydroxyl in tyrosine molecular. Moreover, the mechanical property of silk was protected effectively by the mild coupling modified dyeing, better than the traditional acid dyeing under high temperature for a long time. This facile strategy provides an alternative approach to silk dyeing and benefits the silk applications. 相似文献
77.
A novel optical chemical sensor based on a transparent electrospun nanofibrous scaffold, composed of polycaprolactam (PA6) and 1,10-phenanthroline (Phen), deposited on a glass slide and impregnated with polyvinyl alcohol (PVA) was coupled with UV-vis spectrophotometry and used for colorimetric determination of ferrous ion (Fe2+) and ascorbic acid (AA). The electrospun nanofibers were characterized using scanning electron microscopy (SEM) and Fourier transform infrared spectroscopy (FT-IR) techniques. The main factors affecting performance of the optical sensor (PA6-Phen/PVA@glass) including Phen dosage, pH of sample solution, electrospinning time, polymer solution flowrate, electrospinning voltage, and PVA amount were investigated and the related optimum values were obtained. The analytical merits of the sensor for quantitative determination of Fe2+ and ascorbic acid was evaluated. The limit of detection (LOD) and limit of quantification (LOQ) for Fe2+ were 1 and 3 μg mL-1, respectively. The linear dynamic range (LDR) was 3–150 μg mL-1 with the determination coefficient (R2) of 0.991. The relative standard deviation (RSD %, n=3) for a solution of 60 μg mL-1 was 5.4 %. For determination of AA, LOD and LOQ were obtained equal to 0.5 and 2 μg mL-1, respectively. The linear dynamic range was in the 2–200 μg mL-1 range with a R2 of 0.994. The RSD % at 100 μg mL-1, n=3) was equal to 7.0 %. The sensor was applied successfully to the detection of Fe(II) and AA in real water samples and aspirin tablets. 相似文献
78.
Noureen Arshad Khalid Mahmood Zia Farukh Jabeen Muhammad Naveed Anjum Nadia Akram Muhammad Kaleem Khosa 《Fibers and Polymers》2018,19(11):2219-2228
The research work was carried out to synthesize a series of novel chitosan based water dispersible polyurethanes (CS-WDPUs). The three step synthesis involves the formation of end capped PU-prepolymer was formed through the reaction between polyethylene glycol (PEG) (Mn=600 g/mole, dimethylolpropionic acid (DMPA) and isophorone diisocyanate (IPDI) followed by the preparation of neutralized NCO terminated PU-prepolymer, which lead to the chain extension by using the chitosan. The dispersion of the obtained product was carried out by adding proper proportion of water. The synthesized CS-WDPUs were applied onto the different qualities of plain weave poly-cotton printed and dyed textile swatches by employing pad-dry-cure procedures. The textile assets of the treated and untreated textile swatches were assessed, as color fastness, pilling resistance, tear and tensile strength. The results showed that the chitosan incorporation into PU backbone has significant effect on the assets of treated textiles. These synthesized CS-WDPUs are eco-friendly bio-based finishes with potential applications for polyester/cotton textiles. 相似文献
79.
Hamed Elsayed Rasha Attia Ola Mohamed Ahmed Haroun Nabil El-Sayed 《Fibers and Polymers》2018,19(4):832-842
Leather finishing processes using toxic organic solvent based produce volatile organic compounds (VOC), chronic exposure to this chemicals effect on workers' health causing many diseases especially lung cancer. So, polyurethane waterbased was synthesized for application in leather finishing instead of organic solvent based because it’s economic and safety for industry and workers. Preparation of water-based polyurethane (PU) depends on the reaction of polyethylene glycol (PEG, 300) with isophorone diisocyanate (IPDI) and the reaction of IPDI-1,4-butanediol (BDO) together with dimethylolpropionic acid (DMPA), was synthesized by poly-addition polymerization reaction. PU was then modified with different amounts of silicon dioxide nanoparticles (1-5 % SiO2), used as a binder in leather finishing. Leather coated was characterized physically, chemically and thermally by FTIR, GPC, DLS, TEM, SEM and TGA. The results revel that, water vapor permeability (WVP) of leather coated with PU modified with SiO2 showed improvement due to the existence of SiO2 particles which increases the interspaces of the polyurethane coating. SEM showed that when the amount of SiO2 nanoparticles increases, there is uniform nanoparticles accumulated can be observed. EDX prove the presence of Si and O2 elements and the formation of SiO2 nanoparticles. Mechanical properties discussed that tensile strength; tear strength and elongation at break % increase with increase SiO2 concentration until 3 % SiO2 nanoparticles. TGA showed an improvement of thermal stability of coated leather modified with SiO2. Therefore, this study succeeded in preparation of safe, ecofriendly of water-based polyurethane binders which modified with SiO2 for using in leather finishing. 相似文献
80.
Mochamad Asrofi Hairul Abral Anwar Kasim Adjar Pratoto Melbi Mahardika Ji-Won Park Hyun-Joong Kim 《Fibers and Polymers》2018,19(8):1618-1625
The successful isolation and characterization of water hyacinth fiber (Eichornia crassipes) (WHF) nanocellulose is presented in this study. The novelty was in exploring a wider range of properties of highly purified samples of WHF after each stage of production in more depth. The isolation was accomplished by pulping in a digester and sonication. Morphological changes before and after treatment were demonstrated by scanning electron microscopy (SEM). The lignin and hemicellulose content decreased during chemical treatment. Transmission electron microscopy (TEM) and particle size analyzer (PSA) were used to determine the morphology of WHF after sonication for 1 h. TEM shows that the diameter and length of nanocellulose WHF were 15.61 and 147.4 nm, respectively. The crystallinity index and crystalline domain area significantly increased after chemical treatment. The highest crystallinity index was 84.87 % after an acid hydrolysis process. The increase in crystallinity leads to good thermal stability. Moisture absorption tests of WHF were carried out before and after treatment. The lowest moisture absorption was in the cellulose fiber after sonication (nanocellulose). 相似文献