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Natural Extraction of Dyes from Saffron ‘Crocus sativus L’ Flower Waste, Cotton Dyeing, and Antioxidant Effectiveness
2023
Lachguer, Khadija | Boudadi, Imane | Fayzi, Lahbib | El Merzougui, Soumaya | El Bouchti, Mehdi | Cherkaoui, Omar | Serghini, Mohammed Amine
The production of saffron, the spice obtained from the dried stigmas of Crocus sativus L. (Iridaceae family) flowers, generates, after pruning, considerable quantities of waste containing natural dyes. Saffron flower waste could be a source of extraction of natural dyes with antioxidant activity. In this study, we investigate the possibility of using saffron flower waste for dyeing cotton and evaluating the antioxidant effect of this dye by the DPPH free radical, reducing power and β-carotene bleaching assay. The dye has been evaluated for the composition of the color by the UV-visible spectrum and tested for the dyeing of cotton. The results indicate the presence of polyphenols and flavonoids. The dyeing conditions have been optimized at 6% dye concentration, dye bath pH of 3, dyeing temperature at 98 °C and dyeing time of 60 min. 2% dye concentration with 5 to 10% mordant concentration remains sufficient for dyeing with pre-mordanting. The exhaustion of the bath after dyeing has been improved by a rate of 20% in the case of addition of mordants which have produced a shade of green color. The dye contributes to the significant antioxidant activities with more DPPH scavenging capacity, FRAP reducing power, and β-carotene bleaching inhibition. Cotton fabrics dyed with bio-dyes obtained from saffron flower waste show good color fastness properties and could be a potential source of natural antioxidant agent. It presents an important eco-friendly alternative to synthetic dyes for large-scale application in textile and food industries.
اظهر المزيد [+] اقل [-]Biochar mitigates arsenic-induced human health risks and phytotoxicity in quinoa under saline conditions by modulating ionic and oxidative stress responses
2021
Shabbir, Arslan | Saqib, Muhammad | Murtaza, Ghulam | Abbas, Ghulam | Imran, Muhammad | Rizwan, Muhammad | Naeem, Muhammad Asif | Ali, Shafaqat | Rashad Javeed, Hafiz Muhammad
Arsenic (As) is a toxic metalloid and its widespread contamination in agricultural soils along with soil salinization has become a serious concern for human health and food security. In the present study, the effect of cotton shell biochar (CSBC) in decreasing As-induced phytotoxicity and human health risks in quinoa (Chenopodium quinoa Willd.) grown on As-spiked saline and non-saline soils was evaluated. Quinoa plants were grown on As contaminated (0, 15 and 30 mg kg⁻¹) saline and non-saline soils amended with 0, 1 and 2% CSBC. Results showed that plant growth, grain yield, stomatal conductance and chlorophyll contents of quinoa showed more decline on As contaminated saline soil than non-saline soil. The application of 2% CSBC particularly enhanced plant growth, leaf relative water contents, stomatal conductance, pigment contents and limited the uptake of As and Na as compared to soil without CSBC. Salinity in combination with As trigged the production of H₂O₂ and caused lipid peroxidation of cell membranes. Biochar ameliorated the oxidative stress by increasing the activities of antioxidant enzymes (SOD, POD, CAT). Carcinogenic and non-carcinogenic human health risks were greatly decreased in the presence of biochar. Application of 2% CSBC showed promising results in reducing human health risks and As toxicity in quinoa grown on As contaminated non-saline and saline soils. Further research is needed to evaluate the role of biochar in minimizing As accumulation in other crops on normal as well as salt affected soils under field conditions.
اظهر المزيد [+] اقل [-]Neonicotinoids from coated seeds toxic for honeydew-feeding biological control agents
2021
Calvo-Agudo, Miguel | Dregni, Jonathan | González-Cabrera, Joel | Dicke, Marcel | Heimpel, George E. | Tena, Alejandro
Seed coating (‘seed treatment’) is the leading delivery method of neonicotinoid insecticides in major crops such as soybean, wheat, cotton and maize. However, this prophylactic use of neonicotinoids is widely discussed from the standpoint of environmental costs. Growing soybean plants from neonicotinoid-coated seeds in field, we demonstrate that soybean aphids (Aphis glycines) survived the treatment, and excreted honeydew containing neonicotinoids. Biochemical analyses demonstrated that honeydew excreted by the soybean aphid contained substantial concentrations of neonicotinoids even one month after sowing of the crop. Consuming this honeydew reduced the longevity of two biological control agents of the soybean aphid, the predatory midge Aphidoletes aphidimyza and the parasitic wasp Aphelinus certus. These results have important environmental and economic implications because honeydew is the main carbohydrate source for many beneficial insects in agricultural landscapes.
اظهر المزيد [+] اقل [-]Sponges as bioindicators for microparticulate pollutants?
2021
Girard, Elsa B. | Fuchs, Adrian | Kaliwoda, Melanie | Lasut, Markus | Ploetz, Evelyn | Schmahl, Wolfgang W. | Wörheide, Gert
Amongst other threats, the world’s oceans are faced with man-made pollution, including an increasing number of microparticulate pollutants. Sponges, aquatic filter-feeding animals, are able to incorporate fine foreign particles, and thus may be a potential bioindicator for microparticulate pollutants. To address this question, 15 coral reef demosponges sampled around Bangka Island (North Sulawesi, Indonesia) were analyzed for the nature of their foreign particle content using traditional histological methods, advanced light microscopy, and Raman spectroscopy. Sampled sponges accumulated and embedded the very fine sediment fraction (<200 μm), absent in the surrounding sand, in the ectosome (outer epithelia) and spongin fibers (skeletal elements), which was confirmed by two-photon microscopy. A total of 34 different particle types were identified, of which degraded man-made products, i.e., polystyrene, particulate cotton, titanium dioxide and blue-pigmented particles, were incorporated by eight specimens at concentrations between 91 and 612 particle/g dry sponge tissue. As sponges can weigh several hundreds of grams, we conservatively extrapolate that sponges can incorporate on average 10,000 microparticulate pollutants in their tissue. The uptake of particles, however, appears independent of the material, which suggests that the fluctuation in material ratios is due to the spatial variation of surrounding microparticles. Therefore, particle-bearing sponges have a strong potential to biomonitor microparticulate pollutants, such as microplastics and other degraded industrial products.
اظهر المزيد [+] اقل [-]Effect of biochar on Cd and pyrene removal and bacteria communities variations in soils with culturing ryegrass (Lolium perenne L.)
2020
Li, Guirong | Chen, Fukai | Jia, Shengyong | Wang, Zongshuo | Zuo, Qiting | He, Hongmou
Organic contaminations and heavy metals in soils cause large harm to human and environment, which could be remedied by planting specific plants. The biochars produced by crop straws could provide substantial benefits as a soil amendment. In the present study, biochars based on wheat, corn, soybean, cotton and eggplant straws were produced. The eggplant straws based biochar (ESBC) represented higher Cd and pyrene adsorption capacity than others, which was probably owing to the higher specific surface area and total pore volume, more functional groups and excellent crystallization. And then, ESBC amendment hybrid Ryegrass (Lolium perenne L.) cultivation were investigated to remediate the Cd and pyrene co−contaminated soil. With the leaching amount of 100% (v/w, mL water/g soil) and Cd content of 16.8 mg/kg soil, dosing 3% ESBC (wt%, biochar/soil) could keep 96.2% of the Cd in the 10 cm depth soil layer where the ryegrass root could reach, and it positively help root adsorb contaminations. Compared with the single planting ryegrass, the Cd and pyrene removal efficiencies significantly increased to 22.8% and 76.9% by dosing 3% ESBC, which was mainly related with the increased plant germination of 80% and biomass of 1.29 g after 70 days culture. When the ESBC dosage increased to 5%, more free radicals were injected and the ryegrass germination and biomass decreased to 65% and 0.986 g. Furthermore, when the ESBC was added into the ryegrass culture soil, the proportion of Cd and pyrene degrading bacteria Pseudomonas and Enterobacter significantly increased to 4.46% and 3.85%, which promoted the co−contaminations removal. It is suggested that biochar amendment hybrid ryegrass cultivation would be an effective method to remediate the Cd and pyrene co−contaminated soil.
اظهر المزيد [+] اقل [-]Transgenic insect-resistant Bt cotton expressing Cry1Ac/CpTI does not affect the mirid bug Apolygus lucorum
2020
Niu, Lin | Liu, Fang | Zhang, Shuai | Luo, Junyu | Zhang, Lijuan | Ji, Jichao | Gao, Xueke | Ma, Weihua | Cui, Jinjie
Common varieties of genetically modified (GM) cotton increasingly display insect-resistant properties via expression of bacterial-derived toxins from Bacillus thuringiensis (Bt). This necessitates a deeper understanding of the possible effects of these crops on non-target insects. The mirid bug Apolygus lucorum is a major pest in cotton production in China, however, the effect of GM cotton on this non-target species is currently virtually unknown. This insect is exposed to these transgenic plants by consuming genetically modified (GM) leaves. In this study, laboratory experiments were conducted to assess the toxicity of CCRI41 and CCRI45, (genetically modified cotton varieties which express the toxins Cry1Ac and CpTI (Cowpea Trypsin Inhibitor)) on nymphs and adults of A. lucorum. There was no detectable increase in mortality after A. lucorum fed on GM cotton leaves for 20 days. While we detected trace amounts of Cry1Ac proteins in both A. lucorum nymphs and adults (<10 ng/g fresh weight), the expression of genes related to detoxification did not detectably differ from those feeding on non-GM cotton. Our binding assays did not show Cry1Ac binding to receptors on the midgut brush border membrane from either A. lucorum nymphs or adults. Our findings collectively indicate that feeding on leaves of the GM cotton varieties CCRI41 and CCRI45 have few toxic effects on A. lucorum.
اظهر المزيد [+] اقل [-]A less harmful system of preparing robust fabrics for integrated self-cleaning, oil-water separation and water purification
2019
Yang, Maiping | Jiang, Chi | Liu, Weiqu | Liang, Liyan | Pi, Ke
Although the development of constructing oil-water separation materials is quick, the defects of using harmful regents, weak stability and single function still exist. Here, we report an effective and less-harmful system with poly-dimethylsiloxane (PDMS)/ZnO composite solution to fabricate robust superhydrophobic surfaces for oil-water separation and removal of organic pollutant. The obtained samples were characterized by a range of instruments. The water contact angle (WCA) of coated cotton was 155.6°, which attributed to the synergetic effect of low surface energy of PDMS and roughness of ZnO nanoparticles. The coated cotton was tolerant to mechanical damage, various corrosive solvents and temperature conditions. The emphasis of this study is the combination of superhydrophobicity and photocatalysis, resulting in multifunctional cotton with dual self-cleaning properties, outstanding oil-water separation ability and efficient water purification property. When utilized a simple laboratory facility, the cotton could separate water from oil-water mixture with a high efficiency (99.3%). Furthermore, the dyed water could be purified with coated cotton through photocatalysis under UV light and became colorless. Meanwhile, this mild and facile method could also be utilized to modify other porous substrates, such as PET, silk, non-woven and sponge. Therefore, the characteristics of environmental protection and easy operation make this cotton a desirable candidate for extensive applications in self-cleaning, oil-water separation and water purification.
اظهر المزيد [+] اقل [-]Transgenic Bt cotton expressing Cry1Ac/Cry2Ab or Cry1Ac/EPSPS does not affect the plant bug Adelphocoris suturalis or the pollinating beetle Haptoncus luteolus
2018
Niu, Lin | Tian, Zhenya | Liu, Hui | Zhou, Hao | Ma, Weihua | Lei, Chaoliang | Chen, Lizhen
The widespread cultivation of transgenic Bt cotton makes assessing the potential effects of this recombinant crop on non-target organisms a priority. However, the effect of Bt cotton on many insects is currently virtually unknown. The plant bug Adelphocoris suturalis is now a major pest of cotton in southern China and the beetle Haptoncus luteolus is one of the most ancient cotton pollinators. We conducted laboratory experiments to evaluate the toxicity of the Bt cotton varieties ZMSJ, which expresses the toxins Cry1Ac and Cry2Ab, and ZMKCKC, which expresses Cry1Ac and EPSPS, on adult A. suturalis and H. luteolus. No significant increase in the mortality of either species was detected after feeding on Bt cotton leaves or pollen for 7 days. Trace amounts of Cry1Ac and Cry2Ab proteins could be detected in both species but in vitro binding experiments found no evidence of Cry1Ac and Cry2Ab binding proteins. These results demonstrate that feeding on the leaves or pollen of these two Bt cotton varieties has no toxic effects on adult A. suturalis or H. luteolus.
اظهر المزيد [+] اقل [-]Composition and abundance of macrolitter along the Italian coastline: The first baseline assessment within the european Marine Strategy Framework Directive
2021
Fortibuoni, Tomaso | Amadesi, Barbara | Vlachogianni, Thomais
The main objective of the Marine Strategy Framework Directive (MSFD) was to achieve a Good Environmental Status (GES) in European waters by 2020, according to 11 descriptors. Descriptor 10 is related to marine litter and envisages that the properties and quantities of marine litter are at a level that does not cause harm to the coastal and marine environment. Even if GES was not achieved by 2020, the first MSFD implementation cycle filled many gaps in knowledge. Here we present the first data (2015–2018) on beach litter densities along Italian coasts and discuss lessons learnt and future perspectives. The beach litter median density was 477 items/100 m (interquartile range: 261–934 items/100 m), but subregional differences emerged both in terms of litter quantities and composition. The Adriatic Sea was the most polluted subregion (590 items/100 m), followed by the Western Mediterranean Sea (491 items/100 m) and the Ionian Sea and Central Mediterranean Sea subregion (274 items/100 m). A high presence of aquaculture-related litter (mainly mussel nets) characterised beaches in the Adriatic Sea. At the same time, the numbers of cotton bud sticks were extremely high in some beaches of the Western Mediterranean Sea. General litter (items discarded or left by the public on the coast or inland and carried by winds and rivers or objects originating from tourism and recreation at land or sea, poor waste management practices, etc.) was the most common litter typology (38.8%). The results of this study represent the first baseline to compare achievement towards GES in the next years and the efficacy of the program of measures which entered into force in 2016, concerning beach litter densities and composition. They also highlight the necessity of a joint effort for deploying harmonised marine litter monitoring methodologies across the European Member States to obtain comparable results.
اظهر المزيد [+] اقل [-]Impact of dyes and finishes on the microfibers released on the laundering of cotton knitted fabrics
2021
Zambrano, Marielis C. | Pawlak, Joel J. | Daystar, Jesse | Ankeny, Mary | Venditti, Richard A.
The influence of common textile finishes on cotton fabrics on the generation of microfibers during laundering was assessed. Microfiber release was determined to be in the range of 9000–14,000 particles per gram of cotton fabric. Cotton knitted fabrics treated with softener and durable press generate more microfibers (1.30–1.63 mg/g fabric) during laundering by mass and number than untreated fabric (0.73 mg/g fabric). The fabrics treated with softener generated the longest average microfiber length (0.86 mm), whereas durable press and water repellent treatments produced the shortest average microfiber length (0.62 and 0.63 mm, respectively). In general, the changes in the mechanical properties of the fibers and fabrics due to the finishing treatments are the main factor affecting the microfiber release. The abrasion resistance of the fabrics decreases for durable press treatments and water repellent treatments due to the brittleness in the structure originated by the crosslinking treatment. In the case of the softener treatment, the fabric surface is soft and smooth decreasing the friction coefficient between fibers favoring the fibers loosening from the textile and resulting in a high tendency for fuzz formation and microfiber release. These findings are useful for the textile industry in the design and selection of materials and treatments for the reduction of synthetic or natural microfiber shedding from textiles.
اظهر المزيد [+] اقل [-]