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1.
Int J Biol Macromol ; 253(Pt 4): 127009, 2023 Dec 31.
Artigo em Inglês | MEDLINE | ID: mdl-37734521

RESUMO

This study looked into how well the macro-hollow loofah fiber with and without the bio-attaching with green microalga (Chlamydomonas reinhardtii OR242521) was applied methylene blue elimination from water. Based on the results, the biosorption capacity of loofah sponge for methylene blue significantly increased with the increase of contact time, weight of microalgal biofilm, and methylene blue concentration. The maximum biosorption capacity was achieved after 120 min, after 0.042 mgg-1 biofilm weight, and MB concentration of 140 mgL-1. Furthermore, methylene blue's biosorption capacity was strongly affected by pH, reaching its maximum at pH 7. The biosorption capacity of the bio-attached loofah sponge was much higher than that of the loofah sponge, revealing that the microalgae bio-attachment enhanced the biosorption capacity of the loofah sponge. At the end of the MB biosorption process, the used bio-attached loofah sponge can still be utilized once more for the same purpose after the desorption of MB but with a lower biosorption capacity. Furthermore, the loofah sponge could also be applied as a bio-sorbent after domestic use. According to this study, the loofah sponge with or without algal biofilm attachment could be applied as a low-cost efficient bio-sorbent for methylene blue removal from water. However, the loofah sponge's ability for biosorption was dramatically increased by the bio-attachment of microalgae, making it a more potent bio-sorbent. Likewise, this study offers insights into the variables influencing the biosorption capacity of loofah sponges and bio-attached loofah sponges, which could be beneficial for enhancing the biosorption processes.


Assuntos
Luffa , Microalgas , Poluentes Químicos da Água , Azul de Metileno , Adsorção , Cinética , Água , Concentração de Íons de Hidrogênio
2.
Environ Pollut ; 334: 122185, 2023 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-37442325

RESUMO

Magnetic biochar had been used for the bioremediation of polycyclic aromatic hydrocarbon (PAH)-contaminated sediments. However, the long-term remediation pattern of vertical stratification driven by the application of magnetic biochar and the assembly of microbes had received little attention. In this study, magnetic loofah sponge biochar (MagLsBC), magnetic iron oxide (MagOx) and magnetic coconut shell activated carbon (MagCoAC) were applied for the 900-day remediation of contaminated sediments. Significant (p < 0.05) PAH biodegradation was observed in both the surface and subsurface sediments with MagLsBC addition. However, enhanced PAH biodegradation was observed only in the surface sediments with MagOx and MagCoAC treatments. Magnetotactic bacteria (Magnetococcus) was dominant genera in surface sediments and indigenous PAH degradation bacteria were more abundant in subsurface sediments of MagLsBC relative to other bacterial communities. The network interaction between microbes in surface and subsurface sediments with MagLsBC treatments was a less complex and tighter than those with MagCoAC, MagOx or Control treatments. Long-distance electron transfer rates could be enhanced through cooperation between magnetotactic bacteria and indigenous degradation bacteria, thus accelerating PAH degradation in sediment with MagLsBC treatment, especially in the underlying sediment.


Assuntos
Luffa , Hidrocarbonetos Policíclicos Aromáticos , Hidrocarbonetos Policíclicos Aromáticos/análise , Carvão Vegetal/metabolismo , Luffa/metabolismo , Biodegradação Ambiental , Bactérias/metabolismo , Fenômenos Magnéticos , Sedimentos Geológicos/microbiologia
3.
J Colloid Interface Sci ; 640: 647-655, 2023 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-36893531

RESUMO

Solar-driven water purification has been deemed as a cheap, green and renewable technology to mitigate water shortage and pollution. Herein, a biomass aerogel with hydrophilic-hydrophobic Janus structure has been prepared as solar water evaporator, which is achieved by partially modifying hydrothermal-treated loofah sponge (HLS) with reduced graphene oxide (rGO). It's a rare design philosophy that HLS serves as a substrate with large pores and hydrophilic properties to ensure continuous and effective water transport, and the hydrophobic layer with rGO modification guarantees good salt resistance in seawater desalination with high photothermal conversion efficiency. As a result, the obtained Janus aerogel, p-HLS@rGO-12, exhibits impressive solar-driven evaporation rates of 1.75 kg m-2h-1 and 1.54 kg m-2h-1 for pure water and seawater respectively, with good cycling stability in the evaporation process. Furthermore, p-HLS@rGO-12 also demonstrates outstanding photothermal degradation of rhodamine B (greater than98.8 % in 2 h) and sterilization of E. coli (nearly 100 % in 2 h). This work offers an unusual approach to achieve highly efficient solar-driven steam generation, seawater desalination, organic pollutant degradation, and water disinfection simultaneously. The prepared Janus biomass aerogel holds great potential application in the field of seawater desalination and wastewater purification.

4.
IDCases ; 27: e01395, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35059295

RESUMO

Loofah sponges have been implicated in skin and soft tissue infections due to their ability to harbor bacteria and cause microtrauma to the skin. In this case report, we describe a case of impetigo and cellulitis due to Streptococcus pyogenes complicated by secondary spread through loofah sponge use. The same organism was cultured from the infected body sites and loofah sponge, and a comparative genomic analysis confirmed that the isolates were identical.

5.
Bioresour Technol ; 349: 126534, 2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-34896528

RESUMO

Facile and green fabrication of reduced graphene oxide on loofah sponge (rGOLS) carrier was applied for cell immobilization of ε-Poly-l-lysine (ε-PL) production. Due to surface properties including large specific surface area, high polarity, and low interaction energy, rGOLS-1 was employed as the optimum rGOLS to enhance immobilization of Streptomyces albulus. Compared with raw LS, batch experiments showed rGOLS-1 facilitated superior cell vitality for ε-PL production due to the presence of reduced graphene oxide. In the sequential fed-batch cultivation of Streptomyces albulus using rGOLS-1 with an aerobic plant fibrous-bed bioreactor (rGOLS-1-AFPB), the maximum ε-PL concentration and productivity reached to 39.2 ± 0.63 g/L and 0.48 g/L/h. The cells immobilized in rGOLS-1 with high vitality and ε-PL production efficiency were reused six times over a period of 624 h. This research afforded an effective approach to enhance the fermentation performance of immobilized cells with the design of an advanced immobilization carrier.


Assuntos
Luffa , Streptomyces , Fermentação , Grafite , Luffa/metabolismo , Polilisina , Streptomyces/metabolismo
6.
Molecules ; 26(4)2021 Feb 04.
Artigo em Inglês | MEDLINE | ID: mdl-33557429

RESUMO

Pseudomonas moorei KB4 is capable of degrading paracetamol, but high concentrations of this drug may cause an accumulation of toxic metabolites. It is known that immobilisation can have a protective effect on bacterial cells; therefore, the toxicity and degradation rate of paracetamol by the immobilised strain KB4 were assessed. Strain KB4 was immobilised on a plant sponge. A toxicity assessment was performed by measuring the concentration of ATP using the colony-forming unit (CFU) method. The kinetic parameters of paracetamol degradation were estimated using the Hill equation. Toxicity analysis showed a protective effect of the carrier at low concentrations of paracetamol. Moreover, a pronounced phenomenon of hormesis was observed in the immobilised systems. The obtained kinetic parameters and the course of the kinetic curves clearly indicate a decrease in the degradation activity of cells after their immobilisation. There was a delay in degradation in the systems with free cells without glucose and immobilised cells with glucose. However, it was demonstrated that the immobilised systems can degrade at least ten succeeding cycles of 20 mg/L paracetamol degradation. The obtained results indicate that the immobilised strain may become a useful tool in the process of paracetamol degradation.


Assuntos
Acetaminofen/metabolismo , Células Imobilizadas/metabolismo , Pseudomonas/citologia , Pseudomonas/metabolismo , Acetaminofen/isolamento & purificação , Acetaminofen/farmacologia , Biodegradação Ambiental , Cinética , Pseudomonas/efeitos dos fármacos
7.
Sci Total Environ ; 765: 144253, 2021 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-33418333

RESUMO

Extensive application of imidacloprid (IMI) in pest control and its undesirable removal efficiency enabled it to be a critical global challenge. Low cost, efficient, sustainable and environment-friendly technologies are urgently needed to be developed to remove IMI from water. A novel adsorbent of potassium hydroxide activated magnetic microporous loofah sponge biochar (KOH+Fe/Zn-LBC) was synthesized, as well as its adsorption capacity and mechanisms for IMI were investigated in this study. KOH+Fe/Zn-LBC had the superior pore structure (surface area and pore volume) and its maximum adsorption capacity for IMI could reach 738 mg g-1 at 298 K. Kinetics, isotherms, thermodynamics and characterization analysis suggested that pore filling, hydrogen bonding and π-π conjugation were its main adsorption mechanisms. Additionally, the thermodynamic parameters described that IMI adsorption was a spontaneous, endothermic and less random process. Particularly, the magnetic separation of KOH+Fe/Zn-LBC was beneficial for its reuse. Ultrasound and ethanol co-processing could effectively regenerate the used KOH+Fe/Zn-LBC and maintain its stable sustainable adsorption capacity (99.4% of its fresh adsorption capacity after five reuse cycles). Besides, KOH+Fe/Zn-LBC exhibited a stable adsorption capacity and environmental safety in a wide pH range. Therefore, KOH+Fe/Zn-LBC has the potential to be an efficient, green and sustainable adsorbent for neonicotinoids removal.


Assuntos
Luffa , Poluentes Químicos da Água , Adsorção , Carvão Vegetal , Concentração de Íons de Hidrogênio , Hidróxidos , Cinética , Fenômenos Magnéticos , Neonicotinoides , Nitrocompostos , Compostos de Potássio , Termodinâmica , Poluentes Químicos da Água/análise
8.
ACS Appl Mater Interfaces ; 12(32): 36540-36547, 2020 Aug 12.
Artigo em Inglês | MEDLINE | ID: mdl-32678977

RESUMO

Three-dimensional (3D) wearable piezoresistive sensors with excellent performance are urgently needed in many emerging fields. Herein, a hybrid piezoresistive sensor with 3D structure, which is framed by loofah sponge and coated with reduced graphene oxide modified with carbon black nanoparticles (rGO-CB@LS), was obtained via a facile solvothermal method. The ingenious use of loofah sponge (LS) provides a 3D highly ordered structure with excellent flexibility for the hybrid sensor, which assists the sensor free from the dependence on an organic substrate and eliminates the pollution to the environment. While the addition of carbon black (CB) nanoparticles can reduce the contact resistance between rGO sheets, improve the conductivity and sensitivity effectively, and shorten the response/recovery time of the sensor. An ultralight piezoresistive sensor, which is low cost and environmentally friendly, was obtained under the synergy of LS and rGO-CB, accompanied by high sensitivity and good stability. This novel sensor also exhibits excellent performance in detecting tiny and big human activities, demonstrating its great potential for a new generation of 3D wearable sensors.

9.
Molecules ; 25(4)2020 Feb 17.
Artigo em Inglês | MEDLINE | ID: mdl-32079161

RESUMO

The naproxen-degrading bacterium Bacillus thuringiensis B1(2015b) was immobilised onto loofah sponge and introduced into lab-scale trickling filters. The trickling filters constructed for this study additionally contained stabilised microflora from a functioning wastewater treatment plant to assess the behavior of introduced immobilized biocatalyst in a fully functioning bioremediation system. The immobilised cells degraded naproxen (1 mg/L) faster in the presence of autochthonous microflora than in a monoculture trickling filter. There was also abundant colonization of the loofah sponges by the microorganisms from the system. Analysis of the influence of an acute, short-term naproxen exposure on the indigenous community revealed a significant drop in its diversity and qualitative composition. Bioaugmentation was also not neutral to the microflora. Introducing a new microorganism and increasing the removal of the pollutant caused changes in the microbial community structure and species composition. The incorporation of the immobilised B1(2015b) was successful and the introduced strain colonized the basic carrier in the trickling filter after the complete biodegradation of the naproxen. As a result, the bioremediation system could potentially be used to biodegrade naproxen in the future.


Assuntos
Bacillus thuringiensis/metabolismo , Células Imobilizadas/metabolismo , Luffa/microbiologia , Naproxeno/metabolismo , Bacillus thuringiensis/ultraestrutura , Biodegradação Ambiental , Biofilmes , DNA Ribossômico/genética , Filtração/instrumentação , Luffa/ultraestrutura , Filogenia
10.
Chemosphere ; 242: 125259, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-31896176

RESUMO

Activated carbon (AC), prepared from dried loofah sponge, was supported on nickel foam to fabricate AC/Ni electrodes. The characteristics of ammonium electrosorption on AC/Ni electrodes was studied. Results showed that AC prepared in one-step activation (without pre-pyrolysis), i.e., OAC, had relatively low crystallinity, high mesoporosity, and high specific capacitance compared to those made in two-step carbonation followed by activation. Adsorption and desorption density of NH4+ were measured at constant potential of -1.0 V (vs. Hg/HgO) and +0.1 V (vs. Hg/HgO), respectively. Non-faradaic charging contributed to the electrochemical storage and adsorption of ammonium ions on the AC surface with a maximal charge efficiency of 80%, at an applied potential of -1.0 V (vs. Hg/HgO). Multiple-layer adsorption isotherm better described the electrosorption of ammonium ion on OAC/Ni electrodes yielding a maximum adsorption capacity of 6 mg-N g-1, which was comparable with other similar systems. Overall, results clearly demonstrated the effect of synthesis strategy on the capacitive charging behaviors of AC/Ni electrodes and its relationship to NH4+ electrosorption.


Assuntos
Compostos de Amônio/análise , Carvão Vegetal/química , Luffa/química , Níquel/química , Poluentes Químicos da Água/análise , Purificação da Água/métodos , Adsorção , Capacitância Elétrica , Eletrodos , Íons , Modelos Teóricos , Propriedades de Superfície
11.
J Hazard Mater ; 386: 121651, 2020 03 15.
Artigo em Inglês | MEDLINE | ID: mdl-31767502

RESUMO

In this work, a novel Pd/N-doped loofah sponge-derived biochar (Pd/NLSBC) material with three-dimensional (3D) network structure was prepared through the carbonization-impregnation method and applied as cathode for electrocatalytic bromate removal. The N-doped biochar not only increased the adsorption capacity of electrode, but also facilitated electron transfer, subsequently resulting in the high electrocatalytic activity for bromate removal. The results indicated higher bromate adsorption capacity of Pd/NLSBC electrode was favorable to the electrocatalytic bromate removal. The influences of significant operating factors including calcination temperature, initial solution pH, applied current intensity, and initial bromate concentration on electrocatalytic bromate removal were also optimized. Under the current intensity of 10 mA, Pd/NLSBC-800 exhibited the highest bromate removal efficiency (96.7 %) and the bromide conversion rate reached almost 100 % at the initial bromate concentration of 0.781 µmol L-1. This process could be effectively performed over a wide range of pH (2.0-9.0) and be well fitted to the pseudo-first-order kinetic model under different conditions. The reaction mechanism study indicated that both direct electron transfer and indirect reduction by the active hydrogen atom (H*) contributed to the elctrocatalytic bromate removal. Meanwhile, Pd/NLSBC-800 electrode could maintain its high electrocatalytic activity for bromate removal after five cycles.


Assuntos
Bromatos/química , Carvão Vegetal , Técnicas Eletroquímicas/métodos , Eletrodos , Luffa/química , Nitrogênio/química , Paládio/química , Adsorção , Bromatos/isolamento & purificação , Catálise , Oxirredução , Espectroscopia Fotoeletrônica
12.
Water Environ Res ; 91(7): 581-587, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-30695121

RESUMO

Loofah sponge (LS) was used as carrier for high ammonia wastewater treatment with a sequencing batch biofilm reactor (SBBR), aimed at evaluating its nitrogen removal performance and durability to changeable pH and microbial corrosion. The results indicate that the average removal for COD, NH 4 + -N and total nitrogen (TN) accounted for more than 80%, 90%, and 70%, respectively, in 203 days. After SBBR operation for 108 days, the average weight loss of the loofah sponge was 49.1%. Yet, the main structure of utilized loofah sponge remained unaffected (proved by scanning electron microscopy). Moreover, based on attenuated total reflection-infrared spectroscopy (ATR-IR) and X-ray diffraction (XRD) measurements, cellulose, and hemicelluloses in the loofah sponge were reduced significantly obviously causing the proportion of lignin to increase. During the 108th to 203 days, the removal efficiencies of COD (81.6 ± 7.05%), NH 4 + -N (79.4 ± 8.82%), and TN (79.9 ± 2.85%) remained at a high level. PRACTITIONER POINTS: Loofah sponge had good durability to high ammonia and changeable pH. Lignin was the protective material of loofah sponge for resisting pH fluctuation and microbial corrosion. SBBR maintained a steady nitrogen removal performance with a low COD/N ratio.


Assuntos
Reatores Biológicos , Luffa , Nitrogênio/isolamento & purificação , Purificação da Água , Compostos de Amônio
13.
J Microbiol Biotechnol ; 26(7): 1278-84, 2016 Jul 28.
Artigo em Inglês | MEDLINE | ID: mdl-27090185

RESUMO

Rhizopus chinensis cells immobilized on loofah (Luffa cylindrica) sponges were used to produce biodiesel via the transesterification of soybean oil. In whole-cell immobilization, loofah sponge is considered to be a superior alternative to conventional biomass carriers because of its biodegradable and renewable properties. During cell cultivation, Rhizopus chinensis mycelia can spontaneously and firmly adhere to the surface of loofah sponge particles. The optimal conditions for processing 9.65 g soybean oil at 40°C and 180 rpm using a 3:1 methanol-to-oil molar ratio were found to be 8% cell addition and 3-10% water content (depending on the oil's weight). Under optimal conditions, an over 90% methyl ester yield was achieved after the first reaction batch. The operational stability of immobilized Rhizopus chinensis cells was assayed utilizing a 1:1 methanol-to-oil molar ratio, thus resulting in a 16.5-fold increase in half-life when compared with immobilized cells of the widely studied Rhizopus oryzae. These results suggest that transesterification of vegetable oil using Rhizopus chinensis whole cells immobilized onto loofah sponge is an effective approach for biodiesel production.


Assuntos
Biocombustíveis , Células Imobilizadas/metabolismo , Luffa/metabolismo , Luffa/microbiologia , Poríferos/metabolismo , Poríferos/microbiologia , Rhizopus/metabolismo , Animais , Biocatálise , Biomassa , Metanol/metabolismo , Éteres Metílicos/metabolismo , Água
14.
Materials (Basel) ; 9(11)2016 Nov 10.
Artigo em Inglês | MEDLINE | ID: mdl-28774031

RESUMO

Four porous carbon samples denoted as LSC-1, LSC-2, LCS-3, and LSC-4 were prepared by carbonization of loofah sponge pretreated by ZnCl2 activation, immersion in N,N-dimethylformamide (DMF), DMF-assisted solvothermal and melamine-assisted hydrothermal processes, and the specific surface areas were 1007, 799, 773, and 538 m²·g-1 with mainly micropores, respectively. Electrocapacitive properties of four porous carbon-based electrodes were investigated with cyclic voltammetry, galvanostatic charge-discharge, and electrochemical impedance spectroscopy in symmetric supercapacitors. All the cyclic voltammetries of four types of supercapacitors showed a rectangular shape, even under a high scan rate of 500 mV·s-1. The capacitances of LSC-1, LSC-2, LSC-3, and LSC-4 were 107.4, 92.5, 60.3, and 82.3 F·g-1 at the current density of 0.1 A·g-1, respectively, and LSC-1 displayed the excellent capacitance retention of about 81.3% with a current density up to 5 A·g-1. All supercapacitors showed excellent electrochemical stability, and the LSC-1-based supercapacitor showed a cycle stability with 92.6% capacitance retention after 5000 cycles at 1 A·g-1. The structure-property relationship of LSC samples is discussed and analyzed on the basis of the experimental data.

15.
Rev. Inst. Nac. Hig ; 44(2): 7-11, dic. 2013. graf, ilus
Artigo em Espanhol | LILACS, LIVECS | ID: lil-746321

RESUMO

En algunas regiones del mundo, las plantas originan importantes problemas clínicos, causando gran morbilidad y mortalidad, principalmente después de la intoxicación no intencional. Este trabajo tiene como objetivo principal describir un caso clínico presentado en el Servicio de Toxicología Médica, Hospital “Doctor Leopoldo Manrique Terrero”, Caracas, Venezuela (2012), de una intoxicación con la planta de estropajo (Luffa  cylindrica), perteneciente a la familia de las Cucurbitáceas, usada inadecuadamente como instilación nasal. El análisis clínico otorrinolaringológico permitió evidenciar un cuadro agudo, grave con obstrucción de vías aéreas superiores, producido por el uso tópico de extracto de la planta de estropajo (Luffa  cylindrica), como medicamento nasal para tratar una sinusitis crónica. El paciente presentó 2 horas después de la instilación,  una disfonía,  con un intenso edema de úvula; se encontraba confundido, con cefalea, así como acentuada odinofagia y dificultad respiratoria. Tras la revisión de la literatura se permite plantear que se trata del primer caso referido o publicado de esta inusual intoxicación y daño de vías aéreas superiores ocasionado por esta planta. El paciente fue tratado con oxígeno (SOS), hidrocortisona y clorfeniramina recuperándose después de 48 h de tratamiento sintomático.


In some world regions, plants originate important clinical problems, causing significant morbidity and mortality, mainly after unintentional poisoning. This paper aims to describe a case seen at the Medical Toxicology Service, "Dr. Leopoldo Manrique Terrero " Hospital, Caracas, Venezuela (2012), which was a loofah plant poisoning (Luffa cylindrica), belonging to Cucurbitaceae family, used inappropriately as nasal instillation. The otorhinolaryngology clinical analysis demonstrated an acute, severe upper airway obstruction produced by the topical use of loofah (Luffa cylindrica) plant extract as nasal medication to treat chronic sinusitis. The patient developed 2 hours after instillation, a dysphonia, with intense uvula edema, confusion, headache and sore throat and accentuated respiratory distress. After literature review it is suggested that this is the first referred or published case in this unusual intoxication and upper airway damage caused by this plant. The patient was treated with oxygen (SOS), hydrocortisone and chlorpheniramine recovering after 48 h of symptomatic treatment.


Assuntos
Humanos , Masculino , Feminino , Pessoa de Meia-Idade , Plantas Tóxicas/classificação , Virologia , Edema/diagnóstico , Sinusite , Luffa operculata , Saúde Pública
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