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1.
Int J Biol Macromol ; 272(Pt 1): 132816, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38825273

RESUMO

Modulating the interactions between biopolymer matrix and nanofillers highly determined the mechanical performances of composite packaging materials. Herein, we innovatively proposed a sort of eco-friendly and mechanically robust carboxymethyl cellulose/graphene oxide/tannic acid/polyetherimide (CMC/GO/TA/PEI, CGTP) composite by employing PEI as cross-linker and TA as proton donor. The amidation reaction between -NH2 and -COOH chemically connected the CMC/GO, CMC/CMC and GO/GO and the physical interaction (e.g. hydrogen bonds and molecular entanglements) was beneficial to form dense structures. The chemical/physical bonds among polymers and nanofillers contributed to dissipate the external energy. The toughness was effectively reinforced from 1.68 MJ/m3 for CGTP0 to 4.63 MJ/m3 for CGTP1.0. Furthermore, the CGTP1.0 composite film also delivered improved gas (moisture and oxygen) barriers, UV protection and antimicrobial features. Originating from these merits, the shelf life of fresh fruits (e.g. strawberries, blueberries and cherry tomatoes) was prolonged at least 5 days under ambient conditions when the packaging box was covered by the fabricated CGTP1.0 film. Our findings not only provided a facial strategy to reinforce the interactions between biopolymer matrix and nanofillers, but also boosted the development of eco-friendly packaging materials with robust structures in the area of food packaging.


Assuntos
Carboximetilcelulose Sódica , Embalagem de Alimentos , Frutas , Grafite , Polímeros , Grafite/química , Embalagem de Alimentos/métodos , Carboximetilcelulose Sódica/química , Polímeros/química , Frutas/química , Conservação de Alimentos/métodos , Nanocompostos/química
2.
Int J Biol Macromol ; 266(Pt 1): 131024, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38513907

RESUMO

Improving electron transfer rate of Co species and inhibiting aggregation of metal-organic frameworks (MOFs) particles are essential prerequisites for activating advanced oxidation process in wastewater treatment field. Here, we exploit Cu species with variable valence states to accelerate electron transfer of Co species and then to boost the unsatisfactory degradation efficiency for refractory pharmaceuticals via in-situ growth of copper and cobalt species on l-lysine functionalized carboxylated cellulose nanofibers. Utilizing the synergistic interplay of Co sites and deliberately exposed Cu0/Cu1+ atoms, the subtly designed catalyst exhibited a surprising degradation efficiency (~100 %) toward tetracycline hydrochloride within 10 min (corresponding to a catalytic capacity of 267.71 mg/g) without adjusting temperature and pH. Meanwhile, the catalyst displays good recyclability, well tolerance for coexisting ions and excellent antibacterial performance derived from the intrinsic antibacterial property of Cu-MOF. This research provided a novel strategy to construct MOFs-cellulose materials toward degrading various stubborn antibiotic pollutants.


Assuntos
Antibacterianos , Celulose , Cobalto , Cobre , Estruturas Metalorgânicas , Estruturas Metalorgânicas/química , Celulose/química , Cobre/química , Antibacterianos/química , Antibacterianos/farmacologia , Cobalto/química , Catálise , Tetraciclina/química , Poluentes Químicos da Água/química
3.
Int J Biol Macromol ; 265(Pt 2): 130981, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38513894

RESUMO

High-value utilization of bleached lignin has been widely used in different fields, whereas the investigation on darkened lignin in composite materials was often ignored. In this work, a sort of eco-friendly and structurally robust sodium carboxymethyl cellulose (CMC)/polyvinyl alcohol (PVA)/sodium lignosulfonate (SLS) black composite mulch film was elaborately designed. The chelation and redox reaction effect between Fe ions and SLS lead to the formation of a more quinones structure on lignin, darkening both lignin and the mulch films. The chelation effect between Fe ions and biopolymer formed three-dimensional structures, which can be used as sacrifice bonds to dissipate energy and improve the mechanical properties of the composite films. In particular, the maximum elongation at break and toughness increased from 48.4 % and 1141 kJ/m3 for the CMC/PVA film to 210.9 % and 1426 kJ/m3 for the optimized CMC/PVA/SLS/Fe black mulch film, respectively. In addition, the optimized black mulch film also possesses good soil water retention, thermal preservation effect, controlled urea release, and well biodegradability. This work offered a novel strategy for designing eco-friendly black mulch with reinforced mechanical strength, slow-release urea, soil moisture retention, and heat preservation performances.


Assuntos
Ferro , Lignina , Agricultura/métodos , Solo , Álcool de Polivinil/química , Ureia , Sódio
4.
Int J Biol Macromol ; 261(Pt 1): 129533, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38246448

RESUMO

Constructing high-density contact-separation sites on conductive materials highly determines the sensitivity of flexible resistance-type sensors relying on the crack microstructures. Herein, inspired from the multiple-tentacle structures on octopus, we demonstrated a sort of novel carbonized ZIF-8@loofah (CZL) as conductive material to develop ultrasensitivity flexible sensor, in which the carbonized ZIF-8 nanoparticles (~100 nm) served as tentacles. Originating from the formation of high-density contact-separation sites, the fabricated CZL-based strain sensor delivered ultrahigh sensitivity of GFmax = 15,901, short response time of 22 ms and excellent durability over 10,000 cycles. These features enable the sensor with efficient monitoring capacity for complex human activities, such as pulse rate and phonation. Moreover, when CZL was assembled into triboelectric nanogenerator (TENG), CZL-based TENG can effectively convert the irregular biomechanical energy into electric energy, providing sustainable power supply for the continuous operation of the sensing micro-system. Our findings established a novel platform to develop high-performance self-powered sensing systems of physiological parameter of human inspired from the nature.


Assuntos
Luffa , Octopodiformes , Humanos , Animais , Hidrogéis , Carboximetilcelulose Sódica , Alimentos Marinhos , Movimento Celular
5.
Int J Biol Macromol ; 258(Pt 2): 129154, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38171443

RESUMO

Agricultural by-products like rice husk, bran, and spray corn husks, often utilized as feed, are considered less desirable. This study aims to enhance the utilization rate of these materials by subjecting then to liquid hot water (LHW) pretreatment, followed by enzymatic hydrolysis to produce fermentable sugars. We investigated the production of L-lactic acid using two methods: simultaneous saccharification fermentation (SSF) and separate hydrolysis fermentation (SHF), following varying intensities of LHW pretreatment. The results showed that the optimal enzymatic hydrolysis efficiency was achieved from spray corn husks under the pretreatment conditions of 155 °C and 15 min. SHF was generally more effective than SSF. The glucose L-lactic acid conversion rate in SHF using spray corn husks can reach more than 90 %. Overall, this work proposed a novel, environmental-friendly strategy for efficient and for L- lactic acid production from spray corn husks.


Assuntos
Celulose , Zea mays , Zea mays/metabolismo , Celulose/metabolismo , Ácido Láctico , Fermentação , Água , Hidrólise
6.
Carbohydr Polym ; 313: 120898, 2023 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-37182981

RESUMO

Huge electronic wastes motivated the flourishing of biodegradable electrically conductive cellulosic paper-based functional materials as flexible wearable devices. However, the relatively low sensitivity and unstable output in combination with poor wet strength under high moisture circumstances impeded the practical application. Herein, a superhydrophobic cellulosic paper with ultrahigh sensitivity was proposed by innovatively employing ionic sodium carboxymethyl cellulose (CMC) as bridge to reinforce the interfacial interaction between carbon black (CB) and multilayer graphene (MG) and SiO2 nanoparticles as superhydrophobic layer. The resultant paper-based (PB) sensor displayed excellent strain sensing behaviors, wide working range (-1.0 %-1.0 %), ultrahigh sensitivity (gauge factor, GF = 70.2), and satisfied durability (>10,000 cycles). Moreover, the superhydrophobic surface offered well waterproof and self-cleaning properties, even stable running data without encapsulation under extremely high moisture conditions. Impressively, when the fabricated PB sensor was applied for electronic-skin (E-skin), the signal capture of spatial strain of E-skin upon bodily motion was breezily achieved. Thus, our work not only provides a new pathway for reinforcing the interfacial interaction of electrically conductive carbonaceous materials, but also promises a category of unprecedentedly superhydrophobic cellulosic paper-based strain sensors with ultra-sensitivity in human-machine interfaces field.

7.
Eur J Med Chem ; 257: 115477, 2023 Sep 05.
Artigo em Inglês | MEDLINE | ID: mdl-37210839

RESUMO

As a member of the insulin-receptor superfamily, ALK plays an important role in regulating the growth, proliferation, and survival of cells. ROS1 is highly homologous with ALK, and can also regulate normal physiological activities of cells. The overexpression of both is closely related to the development and metastasis of tumors. Therefore, ALK and ROS1 may serve as important therapeutic targets in non-small cell lung cancer (NSCLC). Clinically, many ALK inhibitors have shown powerful therapeutic efficacy in ALK and ROS1-positive NSCLC patients. However, after some time, patients inevitably develop drug resistance, leading to treatment failure. There are no significant drug breakthroughs in solving the problem of drug-resistant mutations. In this review, we summarize the chemical structural features of several novel dual ALK/ROS1 inhibitors, their inhibitory effect on ALK and ROS1 kinases, and future treatment strategies for patients with ALK and ROS1 inhibitor-resistant mutations.


Assuntos
Carcinoma Pulmonar de Células não Pequenas , Neoplasias Pulmonares , Humanos , Carcinoma Pulmonar de Células não Pequenas/tratamento farmacológico , Carcinoma Pulmonar de Células não Pequenas/patologia , Proteínas Tirosina Quinases , Neoplasias Pulmonares/patologia , Quinase do Linfoma Anaplásico/genética , Proteínas Proto-Oncogênicas , Inibidores de Proteínas Quinases/farmacologia , Inibidores de Proteínas Quinases/uso terapêutico , Inibidores de Proteínas Quinases/química
8.
Carbohydr Polym ; 305: 120570, 2023 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-36737208

RESUMO

Cellulose is the cheapest and mostly widespread green raw material on earth. Due to the easy and versatile developed modification of cellulose, many cellulosic paper-based sustainable materials and their multifunctional applications have attained increasing interest under the background of the implementation of the "plastic ban" policy. However, intrinsic cellulose paper is hydrophilic and non-water-proof, which highly limited its application, thus becoming a bottleneck for the development of "cellulosic paper-based plastic replacement". Unquestioningly, the superhydrophobic modification of cellulosic paper-based materials and the extension of their high value-added applications are highly desired, which is the main content of this review. More importantly, we presented the comprehensive discussion of the functionalized applications of superhydrophobic cellulosic paper-based materials ranging from conventional products to high value-added functional materials such as paper straw and paper mulch film for the first time, which have great industrialization potential and value. This review would offer the valuable guidance and insightful information for the rational construction of sustainable superhydrophobic cellulosic paper for advanced functional devices.

9.
Int J Biol Macromol ; 223(Pt A): 1126-1137, 2022 Dec 31.
Artigo em Inglês | MEDLINE | ID: mdl-36395928

RESUMO

Most traditional food packaging and preservation films suffer from limited stretchability and relatively simple functionality, which severely restricts their practical application. In this study, a highly stretchable and versatile sodium carboxymethyl cellulose (CMC)/polyvinyl alcohol (PVA)/poly(ethylene imine) (PEI)/tannic acid (TA) hydrogel film was elaborately designed and demonstrated as an efficient food packaging and preservation system. The dynamic reversible non-covalent within three-dimensional (3D) network structures served as sacrificial bonds to dissipate the loaded energy and endowed the hydrogel film with excellent elongation ~400 %, which is much larger than that of conventional food packaging films (<50 %). Furthermore, the optimized CMC/PVA/PEI/TA3 hydrogel film delivers versatile performances, including self-healing, whole UV-blocking (<400 nm), strong adhesive strength (234.08 KPa), antioxidation virtues, oxygen barrier (32.64 cm3*µm/(m2*d*KPa)) and water vapor barrier (642.92 g/(m2*24 h)). Notably, the shelf life of fresh strawberries, mangoes, and cherries was prolonged by at least one week under ambient conditions when the packaging box was covered by the fabricated CMC/PVA/PEI/TA3 film. Thus, our work not only provides a highly stretchable and versatile hydrogel film but also boosts the in-depth comprehension and rational design of robust food packaging and preservation films.


Assuntos
Embalagem de Alimentos , Fragaria , Carboximetilcelulose Sódica/química , Álcool de Polivinil/química , Vapor
10.
Int J Biol Macromol ; 209(Pt A): 1450-1456, 2022 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-35469945

RESUMO

Improving the gas molecule barrier performance and structural stability of bio-plastic films dramatically contribute to packaging and protective fields. Herein, we proposed a novel nanocomposite film consisting of cellulose acetate (CA)/polyethyleneimine (PEI)/reduced graphene oxide (rGO)-NiCoFeOx) with high gas barrier property by applying "molecular glue" and "nano-patching" strategies. Systematical investigations demonstrated that the CA/rGO interfacial interaction was effectively enhanced due to the "molecular glue" role of PEI chains via physical/chemical bonds and the defective regions in rGO plane were nano-patched through hydrophilic interactions between edged oxygen-containing functional groups and ultrafine NiCoFeOx nanoparticles (~3 nm). As a result, the oxygen and moisture transmission rates of the prepared CA/PEI/rGO-NPs hybrid film were significantly reduced to 0.31 cm3 ∗ µm/(m2 ∗ d ∗ kPa) and 314.23 g/m2 ∗ 24 h, respectively, which were 99.60% and 54.69% lower than pristine CA films. Meanwhile, the tensile strength of hybrid film was increased from 25.90 MPa to 40.67 MPa. More importantly, the designed nanocomposite film possesses excellent structural stability without obvious GO layer shedding and hydrophobicity attenuation after persistent bending at least 100 times. The exceptional robust and high gas barrier film displays great promising application in food, agriculture, pharmaceuticals and electronic instruments packaging industry.


Assuntos
Grafite , Celulose/análogos & derivados , Celulose/química , Grafite/química , Oxigênio/química , Polietilenoimina
11.
Sci Total Environ ; 822: 153650, 2022 May 20.
Artigo em Inglês | MEDLINE | ID: mdl-35124059

RESUMO

With the push for sustainable design strategies, recyclable packaging is widely favored by the public in the express delivery industry due to its potential for lowering environmental burden and solving climatic challenges. The goal of this paper was to quantify and integrate the environmental footprints of polypropylene hollow board express box (PPH-EB) and establish evaluation model between the recyclable ability and environment performance (EMRE) based on life cycle assessment. This work was carried out by multiple indicators to avoid environmental problem-shifting, and corrugated cartons express box (C-EB) was taken as control objects. The results show that integrated index of PPH-EB is 94.42% lower than that of C-EB. Industrial Water Use (IWU), Primary Energy Demand (PED) and SO2 are major factors affecting results of PPH-EB, which mainly come from polypropylene particles and water resource consumption from recycle process. The most obvious advantage of PPH-EB compared with C-EB is the nearly 1700 times difference in normalized COD index caused by direct emission of paper preparation process. Scenario analysis showed that integrated index of PPH-EB was lower than that of traditional corrugated cartons after more than twice of use, but if the recycling times of PPH-EB continued to increase, the effect on reducing environmental burden was no longer significant. Therefore, although the recyclable times plays a role in decreasing the environmental impact, it is not a permanent strategy. In the design stage of the recyclable express box, the recyclable ability should be reasonably designed through EMRE, so as to minimize the environmental burden.


Assuntos
Polipropilenos , Reciclagem , Meio Ambiente , Embalagem de Produtos
12.
Sci Total Environ ; 788: 147852, 2021 Sep 20.
Artigo em Inglês | MEDLINE | ID: mdl-34134360

RESUMO

The use of functional fillers added to PLA-based products can be beneficial in terms of cost reduction and properties improvement. The existing life cycle assessment of PLA containers mainly focuses on the greenhouse gas (GHG) emission of PLA material model without fillers, and overlooked environmental impacts of functional fillers and the significant environmental problem-shifting on other indicators. This paper presents a life cycle assessment (LCA) of cooking oil bottles made from PLA, PLA/Fibers and PLA/CaCO3 considering a wide spectrum impacts, and compares the environmental profile of them based on normalization and weighting analysis. The functional unit was set at 1000 bottles of 900 mL. The system boundary is from cradle to gate, including PLA-based particles production, bottle processing and transportation. The results showed that the contribution of the primary energy demand (PED) index of PLA-based bottles accounted for 159% to 192% of the global warming potential (GWP) index, which may be overlooked in previous studies. Compared to PLA and PLA/Fibers bottles, PLA/CaCO3 bottles have lower environmental impacts in most categories and the lowest integrated impact index. In terms of PLA/CaCO3 bottles, PLA particles and electricity contributed the most to energy conservation and emission reduction (ECER) results, accounting for 63.09% and 28.26% to the integrated impacts index, respectively. The results imply that the use of fillers in PLA bottles tends to reduce the environmental impacts, especially calcium carbonate can efficiently minimize environmental impacts of PLA-based bottles. And PED, SO2 and NOX indicators ranking above CO2 should be taken into consideration to avoid the environmental problem-shifting, which can provide valuable reference for the creation of the method of making biodegradable plastic and carbon neutral policies.

13.
Front Chem ; 9: 672051, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33996765

RESUMO

A novel and efficient C 3-H vinylation reaction with quinoxalin-2(1H)-one as the substrate, in the presence of alkenes, under metal-free conditions, is reported herein. The reaction leads to the formation of new carbon-carbon bonds that exhibit moderate to good reactivities. The vinylation of quinoxalin-2(1H)-ones, in the presence of alkenes, is an attractive process that can be potentially utilized to produce biologically active 3-vinylated quinoxalin-2(1H)-ones.

14.
Carbohydr Polym ; 253: 117227, 2021 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-33278987

RESUMO

A paper-based packaging material with improved air barrier and water vapor permeability (WVP) properties was synthesized based on layer-by-layer assembly consisted of poly(ethylenimine) (PEI)/graphene oxide (GO) on a filter paper substrate. The effect of the pH of GO suspension on the zeta potential and air permeability (AP) of the modified paper was investigated in detail. The results indicated that the pH of GO suspension resulted in significant difference in the AP of the modified paper. Compare with the pristine paper, the AP of the modified paper with (PEI/GO)10 multilayer films synthesized at pH 2.5 decreased by 99.99 %, while the WVP increased by 15.82 %. The modified paper as packaging material could prolong the shelf-life of oyster mushroom, indicating the modified paper has huge potential application on the preservation of agricultural products.

15.
Int J Biol Macromol ; 164: 1898-1907, 2020 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-32800954

RESUMO

With the current global outbreak of novel coronaviruses, the fabrication of decomposable wet wipe with sufficient wet strength to meet daily use is promising but still challenging, especially when renewable cellulose was employed. In this work, a decomposable cellulose-based wet wipe substrate is demonstrated by introducing a synthetic N-vinyl pyrrolidone-glycidyl methacrylate (NVP-GMA) adhesive on the cellulose surface. Experimental results reveal that the NVP-GMA adhesive not only significantly facilitates the chemical bonding between cellulose fibers in the wet state, but also increase the surface wettability and water retention. The as-fabricated cellulose-based wet wipe substrate displays a superb water retention capacity of 1.9 times, an excellent water absorption capacity (completely wetted with 0° water contact angle), and a perfect wet tensile index of 3.32 N.m.g-1. It is far better than state-of-the-art wet toilet wipe on the market (non-woven). The prepared renewable and degradable cellulose-based substrate with excellent mechanical strength has potential application prospects in diverse commercially available products such as sanitary and medical wet wipes.


Assuntos
Plásticos Biodegradáveis/síntese química , Compostos de Epóxi/química , Metacrilatos/química , Pirrolidinonas/química , Adesivos/química , Antivirais/química , Celulose/química , Resistência à Tração , Água/química , Molhabilidade
16.
Polymers (Basel) ; 12(3)2020 Mar 06.
Artigo em Inglês | MEDLINE | ID: mdl-32155926

RESUMO

The aim of this study was to investigate the ultrasound-assisted alkaline extraction process and structural properties of hemicellulose from sugarcane bagasse pith. Response surface model (RSM) was established in order to optimize the extraction conditions for the highest hemicellulose yield based on the single-factor experiments. A maximum total hemicellulose yield of 23.05% was obtained under the optimal conditions of ultrasonic treatment time of 28 min, KOH mass concentration of 3.7%, and extraction temperature of 53 °C, and it evidently increased 3.24% compared without ultrasound-assisted extraction. The obtained hemicellulose was analyzed by Fourier transform infrared (FT-IR) spectroscopy. The monosaccharide composition and average molecular weight of hemicellulose were characterized by using ion chromatography (IC) and gel permeation chromatography (GPC). The results indicated that xylose was dominant component in water-soluble hemicellulose (WH, 69.05%) and alkali-soluble hemicellulose (AH, 85.83%), respectively. Furthermore, the monosaccharides(otherwise xylose) and uronic acids contents of WH were higher than that of AH. Weight average molecular weight of WH was 29923 g/mol, lower than that of AH (74872 g/mol). These results indicate that ultrasonic-assisted alkaline extraction is an efficient approach for the separation of hemicellulose from sugarcane bagasse pith.

17.
Int J Mol Med ; 45(3): 919-930, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-31985017

RESUMO

3,4­Dihydroxyacetophenone (DHAP) exerts therapeutic effects on cardiovascular disease and pulmonary heart disease. However, it is not utilized as a clinical drug due to its rapid metabolism, short­acting effect and low oral bioavailability. In the present study, three derivatives of DHAP, including 4­acetyl­1,2­phenylene dipropionate (APDP), 1­(3­hydroxy­4­phenoxy­phenyl)­ethanone (HPPE) and a polymer derivative, PEG­DHAP, were synthesized via the esterification or etherification of hydroxyls at C3 and C4, which are the prime metabolism sites of DHAP. The physicochemical properties, pharmacokinetic and antiplatelet aggregation activities of these derivatives were measured to determine whether they can improve the defects of DHAP. The results revealed that APDP and HPPE exhibited markedly lower water solubility and higher oil­water partition coefficients compared to DHAP. APDP rapidly transformed into DHAP in vivo and in vitro, indicating that there were no significant differences in the values of mean residence time in vivo [MRT (0­t)], half­life [t1/2], oral bioavailability and antiplatelet aggregation activity in vivo and in vitro between the two agents. HPPE partially released DHAP for a period of time following oral administration. PEG­DHAP contained 12.47% DHAP dispersed into nanoparticles with a mean particle size of 260.90 nm. This was administered in aqueous solution and was demonstrated to release DHAP slowly following oral administration. These two derivatives significantly prolonged the in vivo acting time and increased the oral bioavailability of DHAP: Following intragastric administration, their MRT (0­t) and t1/2 values were 3.55­11.47­ and 6.63­11.25­fold higher compared with those of DHAP, respectively. Additionally, their relative bioavailability was 394.79 and 331.88%, respectively, and they exhibited longer acting times of significant antiplatelet aggregation activity. The results of the present study may thus provide a reference for the development of DHAP as an oral drug. Furthermore, the results if this study may prove to be useful to researchers addressing the issue of the poor bioavailability of phenolic drugs.


Assuntos
Acetofenonas/química , Agregação Plaquetária/efeitos dos fármacos , Acetofenonas/administração & dosagem , Administração Oral , Animais , Disponibilidade Biológica , Cromatografia Líquida de Alta Pressão , Difosfonatos/química , Feminino , Masculino , Coelhos , Ratos Wistar , Solubilidade
18.
Int J Mol Sci ; 21(2)2020 Jan 09.
Artigo em Inglês | MEDLINE | ID: mdl-31936535

RESUMO

Artificial light at night (ALAN/A) can not only alter the behavior and communication of biological organisms, it can also interact with other stressors. Despite its widespread use and the numerous potential ecological effects, little is known about the impact of ALAN on plant litter decomposition under cadmium (Cd) pollution in aquatic ecosystems. In an indoor microcosm experiment, we tested single and combined effects of ALAN and Cd on the activities and community structure of fungi associated with plant litter. The results showed that ALAN and/or Cd can change both water and leaf litter characteristics. ALAN exposure not only altered fungal community structure and their correlations, but also increased the activities of alkaline phosphatase, ß-glucosidase, and cellobiohydrolase. The leaf litter decomposition rate was 71% higher in the A-Cd treatment than that in the N-Cd treatment, indicating that the presence of ALAN weakened the negative impact of Cd on leaf litter decomposition. These results suggested that ALAN exposure mitigated the negative effect of Cd on leaf litter decomposition, contributing to the duel effect of ALAN on leaf litter decomposition. Overall, the results expand our understanding of ALAN on the environment and highlight the contribution of ALAN to Cd toxicity in aquatic ecosystems.


Assuntos
Cádmio/toxicidade , Poluição Ambiental , Luz , Microbiota/efeitos dos fármacos , Folhas de Planta/microbiologia , Biomassa , Análise Discriminante , Espaço Extracelular/enzimologia , Fungos/classificação , Fungos/efeitos dos fármacos , Folhas de Planta/química , Folhas de Planta/efeitos dos fármacos , Rios/química , Especificidade da Espécie , Água/química
19.
Ecotoxicol Environ Saf ; 191: 110014, 2020 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-31810590

RESUMO

Artificial light at night (ALAN, also known as light pollution) has been proved to be a contributor to environmental change and a biodiversity threat worldwide, yet little is known about its potential interaction with different metal pollutants, such as arsenic (As), one of the largest threats to aquatic ecosystems. To narrow this gap, an indoor microcosm study was performed using an ALAN simulation device to examine whether ALAN exposure altered the impact of arsenic on plant litter decomposition and its associated fungi. Results revealed that microbial decomposers involved in the conversion of As(III) to As(V), and ALAN exposure enhanced this effect; ALAN or arsenic only exposure altered fungal community composition and the correlations between fungi species, as well as stimulated or inhibited litter decomposition, respectively. The negative effects of arsenic on the decomposition of Pterocarya stenoptera leaf litter was alleviated by ALAN resulting in the enhanced photodegradation of leaf litter lignin and microbiological oxidation of As(III) to As(V), the increased microbial biomass and CBH activity, as well as the enhanced correlations between CBH and litter decomposition rate. Overall, results expand our understanding of ALAN on environment and highlight the contribution of ALAN to the toxicity of arsenic in aquatic ecosystems.


Assuntos
Arsênio/metabolismo , Poluição Ambiental , Luz , Rios/química , Poluentes Químicos da Água/metabolismo , Arsênio/toxicidade , Biodiversidade , Biomassa , Fungos/efeitos dos fármacos , Fungos/metabolismo , Fungos/efeitos da radiação , Lignina/metabolismo , Folhas de Planta/metabolismo , Poluentes Químicos da Água/toxicidade
20.
Bull Environ Contam Toxicol ; 103(6): 802-807, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31587082

RESUMO

In this work, we assessed the toxic effects of ZnO nanoparticles (NPs; 1, 10, and 50 mg L-1) and the corresponding dissoluble Zn ions (0.71, 8.66, and 35.59 mg L-1) on Microcystis aeruginosa. After chronic exposure (28 days), significantly higher growth inhibition was observed under ZnO NPs at 1 mg L-1 (47%) than under Zn ions at 0.71 mg L-1 (-15%). The opposite effect pattern was observed for ZnO NPs at 10 (71% vs. 80%) and 50 mg L-1 (73% vs. 95%) compared to Zn ions at the corresponding concentrations. After 7 days of exposure, ZnO NPs at 10 and 50 mg L-1 led to an increase of 83 and 53% in malondialdehyde content, as well as an increase of 106 and 61% in superoxide dismutase activity, respectively. However, Zn ions at the corresponding concentrations showed negligible impacts on the two parameters. The different results indicate that the insoluble NPs during the initial exposure mostly account for lipid peroxidation, which further lead to microalgal antioxidant response. During the subsequent exposure, the contributors of ZnO NP toxicity shift with the concentration and exposure time of ZnO NPs. In conclusion, the study presents new insights into the different contributions of insoluble NPs and dissoluble metallic ions to metallic NP toxicity.


Assuntos
Nanopartículas Metálicas/toxicidade , Microcystis/efeitos dos fármacos , Poluentes Químicos da Água/toxicidade , Óxido de Zinco/toxicidade , Zinco/toxicidade , Antioxidantes/metabolismo , Relação Dose-Resposta a Droga , Íons , Peroxidação de Lipídeos/efeitos dos fármacos , Malondialdeído/metabolismo , Microcystis/metabolismo
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