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1.
Environ Sci Pollut Res Int ; 31(17): 24815-24835, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38530525

RESUMEN

Recently, nanoparticles have drawn a lot of interest as catalysts to enhance the effectiveness and output of biohydrogen generation processes. This review article provides a comprehensive bibliometric analysis of the significance of nanotechnology in dark fermentative biohydrogen production. The study examines the scientific literature from the database of The Web of Science© while the bibliometric investigation utilized VOSviewer© and Bibliometrix software tools to conduct the analysis. The findings revealed that a total of 232 articles focused on studying dark fermentation for hydrogen production throughout the entire duration. The extracted data was used to analyze publication trends, authorship patterns, and geographic distribution along with types and effects of nanoparticles on the microbial community responsible for dark fermentative biohydrogen production. The findings of this bibliometric analysis provide valuable insights into the advancements and achievements in the utilization of nanoparticles in the dark fermentation process used to produce biohydrogen.


Asunto(s)
Hidrógeno , Nanotecnología , Fermentación , Hidrógeno/análisis , Biocombustibles
2.
World Neurosurg X ; 23: 100356, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38549761

RESUMEN

Purpose: We hypothesize that lower grade gliomas (LGG) can be identified and classified into two distinct subtypes: radiologically circumscribed Lower-Grade Gliomas (cLGG) and infiltrating Lower-Grade Gliomas (iLGG) based on radiological parameters and that these two different subtypes behave differently in terms of clinical outcomes. Methods: We conducted a retrospective cohort study on surgical patients diagnosed with lower grade glioma over five years. Patient records and MRIs were reviewed, and neurosurgeons classified tumors into cLGG and iLGG groups. Results: From the 165 patients in our cohort, 30 (18.2%) patients were classified as cLGG and 135 (81.8%) patients were classified as iLGG Mean age in cLGG was 31.4 years while mean age in iLGG was 37.9 years (p = 0.004). There was significant difference in mean blood loss between cLGG and iLGG groups (270 and 411 ml respectively, p = 0.020). cLGG had a significantly higher proportion of grade II tumors (p < 0.001). The overall mean survival time for the iLGG group was 14.96 ± 1.23 months, and 18.77 ± 2.72 months for the cLGG group. In univariate cox regression, the survival difference between LGG groups was not significant (HR = 0.888, p = 0.581), however on multivariate regression cLGG showed a significant (aHZ = 0.443, p = 0.015) positive correlation with survival. Intense contrast enhancement (HZ = 41.468, p = 0.018), blood loss (HZ = 1.002, p = 0.049), and moderately high Ki-67 (HZ = 4.589, p = 0.032) were also significant on univariate analyses.Conclusion: cLGG and iLGG are radiologically distinct groups with separate prognoses, surgical experience, and associations.

3.
Molecules ; 28(3)2023 Feb 01.
Artículo en Inglés | MEDLINE | ID: mdl-36771037

RESUMEN

Water contaminated with heavy metals constitutes an important threat. This threat is a real problem with a negative impact in some developing countries where untreated industrial effluents are used for irrigation. The present study examines heavy metals in wastewater-irrigated vegetables (apple gourd, spinach, cauliflower, sponge gourd, and coriander) water, and soil from Chenab Nagar, Chiniot, Pakistan. In particular, the metals quantified were cadmium (Cd), chromium (Cr), cobalt (Co), nickel (Ni), lead (Pb), and manganese (Mn). Among them, Cr and Co in crops irrigated -wastewater exceeded the levels recommended by the World Health Organization (WHO). In contrast, Ni, Cu, Pb, and Mn concentrations were in line with WHO standards. Compared with the limits established by the Food and Agriculture Organization of the United Nations (FAO), all the study vegetables presented higher (thus unsafe) concentrations of Cd (0.38 to 1.205 mg/Kg). There were also unsafe concentrations of Cr in coriander, sponge gourd, and cauliflower. Pb was found at an unsafe concentration (0.59 mg/Kg) in cauliflower. Conversely, Ni and Mn concentrations were below the maximum permissible limits by WHO, and FAO in all of the analyzed samples. The contamination load index (CLI) in soil, bioconcentration factor (BCF) in plants, daily intake of metals (DIM), and health risk index (HRI) have also been evaluated to estimate the potential risk to human health in that area. We have found an important risk of transitions of Pb, Cd, Cr, and Co from water/soil to the edible part of the plant. The highest HRI value associated with Cd (6.10-13.85) followed by Cr (1.25-7.67) for all vegetable samples presented them as high health risk metal contaminants. If the issue is not addressed, consumption of wastewater-irrigated vegetables will continue posing a health risk.


Asunto(s)
Metales Pesados , Contaminantes del Suelo , Humanos , Verduras , Aguas Residuales , Cadmio , Plomo , Monitoreo del Ambiente , Metales Pesados/toxicidad , Metales Pesados/análisis , Níquel , Cromo/toxicidad , Cobalto , Suelo , Manganeso , Agua , Contaminantes del Suelo/toxicidad , Contaminantes del Suelo/análisis , Medición de Riesgo
4.
Bioprocess Biosyst Eng ; 46(3): 453-465, 2023 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-36454313

RESUMEN

Dye-contaminated wastewater discharge from textile and dye manufacturing industries is reported as a world worse water polluter due to the toxic and mutagenic behavior of dyes. Peroxidase, one of the key enzymes of oxidoreductases, is widely distributed in nature and has been currently exploited in industries for various applications. Widespread applications of peroxidases are associated with their nonspecific nature towards a wide spectrum of substrates such as phenols, aromatic amines, pesticides, antibiotics, and synthetic dyes. The present study explored the potential of ammonium sulfate precipitated partially purified Brassica oleracea L. var. botrytis leaves peroxidase for degradation of reactive textile dyes Remazol Turquoise Blue 133 G and Drim Red CL4BN. Various physico-chemical parameters such as pH (2-9), temperature (20-70 â„ƒ), enzyme activity (3-24 U/mL), concentrations of H2O2 (0.4-1.4 Mm) and dye (10-100 mg/L) were optimized for enzymatic decolorization of both dyes' solution. Studies revealed that maximum degradation (95%) of Remazol Turquoise Blue 133 G with peroxidase was achieved with 25 mg/L of initial dye concentration, in the presence of 0.8 mM hydrogen peroxide with 45 min of incubation time, at pH 3, 4, and 5, and 70 °C. Maximal decolorization (97%) of Drim Red CL4BN was obtained at pH 2.0, in 10 min of incubation time at 45 â„ƒ using o-dianisidine hydrochloride as a redox mediator. In conclusion, the findings illustrate the prospect of Brassica oleracea peroxidase to remediate dye pollutants and dye-based industrial effluents in a green technology theme.


Asunto(s)
Brassica , Peroxidasa , Botrytis/metabolismo , Peróxido de Hidrógeno , Peroxidasas/metabolismo , Colorantes/metabolismo , Industria Textil , Textiles , Hojas de la Planta/metabolismo , Biodegradación Ambiental
5.
Biomed Res Int ; 2022: 4987929, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36325499

RESUMEN

Medicinal plants are used to control and remediate oxidative stress related diseases caused by free radicals. Thus, these plants find their use as remedy. Moringa oleifera is an extremely valued plant for its medicinal properties. Herein, two indigenously produced accessions of Moringa oleifera seeds [originated from Multan (M-Mln) and India (PKM1)] were investigated for their antioxidant properties by 2.2-Diphenyl-1picrylhydrazyl (DPPH) assay, total phenolics content and total flavonoids content. The presence of various phenolics as well as flavonoids was further confirmed by high performance liquid chromatography. Moreover, fourier transform infrared spectroscopy detected the presence of various functional groups. In conclusion, these findings revealed that the methanol extract of M-Mln variety seeds showed high antioxidant potential, having IC50 value of 84 µg/ml. While, hexane extract of PKM1 showed least activity. The methanol extract of M-Mln was found to show highest total phenolics content as 33.83 ± 1.19 mg GAE/g. The methanol extract of M-Mln was found to show highest total flavonoids content as 76.07 ± 1.10 mg CAE/g. The hexane extract of PKM1 was found to show least total flavonoids content as 22.47 ± 1.70 mg CAE/g. The detection of phenolics (ferulic acid, caffeic acid, chlorogenic acid, coumaric acid, and gallic acid) as well as flavonoids (catechin and quercetin) revealed the potential of methanol extracts of both varieties as a good source of antioxidants. The results indicated the importance of seed extracts in the treatment of oxidative stress related diseases. In future, the use of natural antioxidants will prevent the progression of diseases.


Asunto(s)
Moringa oleifera , Moringa oleifera/química , Antioxidantes/química , Hexanos , Metanol , Extractos Vegetales/química , Semillas/química , Flavonoides/análisis , Fenoles/análisis , Hojas de la Planta/química
6.
J Pak Med Assoc ; 72(4): 764-766, 2022 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-35614619

RESUMEN

Patients with Down's syndrome exhibit a unique pattern for a number of malignant conditions but there is inconsistent data for the risk of oesophageal cancer. We present a case of early-onset aggressive oesophageal carcinoma in a young male patient diagnosed with Trisomy 21, who presented with complaints of progressive dysphagia, vomiting, voice change and weight loss. Barium swallow showed shouldering sign at distal oesophagus. GI Endoscopy revealed an irregular growth at 20cm from incisors obstructing the lumen. Histopathology confirmed well-differentiated adenocarcinoma. CT scan unmasked a circumferential mass involving the dorsal oesophagus with multiple enlarged nodes along with infiltration of basal segments of left lung staging the tumour as T3N1M0. A metallic stent was placed endoscopically through the stenotic tumour and the patient was referred for chemoradiotherapy. Contrary to the literature proposing a decreased incidence of solid tumours, this is a case reporting early-onset aggressive oesophageal carcinoma in a patient with Down's syndrome.


Asunto(s)
Adenocarcinoma , Síndrome de Down , Neoplasias Esofágicas , Adenocarcinoma/complicaciones , Adenocarcinoma/terapia , Síndrome de Down/complicaciones , Neoplasias Esofágicas/complicaciones , Neoplasias Esofágicas/terapia , Humanos , Masculino , Radiografía
7.
J Neurooncol ; 156(2): 217-231, 2022 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-35020109

RESUMEN

INTRODUCTION: Being the most common primary brain tumor, glioblastoma presents as an extremely challenging malignancy to treat with dismal outcomes despite treatment. Varying molecular epidemiology of glioblastoma between patients and intra-tumoral heterogeneity explains the failure of current one-size-fits-all treatment modalities. Radiomics uses machine learning to identify salient features of the tumor on brain imaging and promises patient-specific management in glioblastoma patients. METHODS: We performed a comprehensive review of the available literature on studies investigating the role of radiomics and radiogenomics models for the diagnosis, stratification, prognostication as well as treatment planning and monitoring of glioblastoma. RESULTS: Classifiers based on a combination of various MRI sequences, genetic information and clinical data can predict non-invasive tumor diagnosis, overall survival and treatment response with reasonable accuracy. However, the use of radiomics for glioblastoma treatment remains in infancy as larger sample sizes, standardized image acquisition and data extraction techniques are needed to develop machine learning models that can be translated effectively into clinical practice. CONCLUSION: Radiomics has the potential to transform the scope of glioblastoma management through personalized medicine.


Asunto(s)
Neoplasias Encefálicas , Glioblastoma , Neoplasias Encefálicas/diagnóstico por imagen , Neoplasias Encefálicas/genética , Neoplasias Encefálicas/terapia , Glioblastoma/diagnóstico por imagen , Glioblastoma/genética , Glioblastoma/terapia , Humanos , Aprendizaje Automático , Imagen por Resonancia Magnética , Medicina de Precisión
8.
Biomed Res Int ; 2021: 3094571, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34725636

RESUMEN

Obesity is a chronic metabolic and noncommunicable disease that affects 50% of world population. Reactive oxygen species and oxidative stress are interconnected with the obesity and several metabolic disorders, gaining the attention of scientific community to combat this problem naturally. Among various fruits, mango as a yellow fruit is rich in polyphenols, carotenoids, terpenes, and flavonoids that act as antioxidants to protect against free radicals produced in the body. The present study was performed to explore in vivo antioxidant potential of mango peels against dyslipidemia and oxidative stress in overweight subjects. The female volunteers (n = 31) between 25 and 45 years of age having a body mass index (BMI) of 25.0-29.9 (overweight) were included in this study, while participants with complications as diabetes, hypertension, cardiovascular, and liver diseases were excluded. The treatment group consumed 1 g mango peel powder for 84 days. The subjects were analyzed for biochemical analysis, antioxidant status, and anthropometric measurements at baseline and end of the study period. Further, at the end of study, the safety evaluation tests were also performed. The results showed that upon consumption of mango peel powder, low-density lipoproteins (LDL), cholesterol, triglyceride, urea, and creatinine levels were decreased and high-density lipoprotein (HDL) level was increased (P ≤ 0.05), while thiobarbituric acid reactive substances (TBARS) showed increased antioxidant status (P ≤ 0.05) which suggests that mango peels have a strong management potential against oxidative stress and dyslipidemia in obese subjects.


Asunto(s)
Dislipidemias/dietoterapia , Mangifera/metabolismo , Obesidad/dietoterapia , Adulto , Antioxidantes/química , Índice de Masa Corporal , Carotenoides/metabolismo , Femenino , Flavonoides/análisis , Frutas/química , Humanos , Obesidad/metabolismo , Sobrepeso/dietoterapia , Estrés Oxidativo/efectos de los fármacos , Extractos Vegetales/farmacología , Especies Reactivas de Oxígeno/metabolismo , Triglicéridos/análisis
9.
J Basic Microbiol ; 61(11): 960-981, 2021 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-34608659

RESUMEN

Environmental protection from emerging pollutants has become a significant challenge for mankind as an increasing number of contaminants, including synthetic dyes and polycyclic aromatic hydrocarbons (PAHs), represent a serious risk to ecological and environmental balance. Most synthetic dyes have complex aromatic structures and are resistant to degrade by classical approaches, such as physical and chemical processes, including adsorption, chemical coagulation, flocculation, ion exchange, membrane separation, froth flotation, and reverse osmosis. Enzymes-assisted catalytic transformation of pollutants has become a potential alternative to classical methods because of their ability to react with complex compounds, a quick degradation rate, and producing less harmful by-products. Plant peroxidases, and microbial laccase and lignin-degrading peroxidases (manganese and lignin peroxidase) have gained significant attention for treating aromatic waste due to their capability of oxidizing and detoxifying a wide range of recalcitrant xenobiotics, including PAHs and synthetic dyes. Peroxidases being efficient biocatalysts detoxify an array of toxic compounds by simple free-radical mechanism resulting in the formation of oxidized and depolymerized products of significantly reduced toxicity. Moreover, it is an ecofriendly and economically favorable approach towards the biodegradation of recalcitrant and toxic industrial waste. Among microbial and plant peroxidases, bacterial enzymes have broad substrate specificity and can transform a wide range of recalcitrant substrates. Ligninolytic enzymes oxidize the aromatic ring into quinones and acids by producing free hydroxyl radicals instead of dihydrodiols and mineralize aromatic hydrocarbon in combination with cytochrome P450, monooxygenases, and epoxide hydrolases. In the review, an attempt has been made to provide detailed knowledge about the availability of inexpensive peroxidases sources, their mechanism of action, and degradation potential. The present review summarizes the exploitation of peroxidases from plants, bacteria, and fungus (manganese peroxidase, lignin peroxidase, and laccases) for detoxification and degradation of textile dyes as well as PAHs. Conclusively, peroxidases have great potential to react with almost all classes of synthetic dyes and most PAHs due to broad substrate specificity and transformed them into less harmful metabolites.


Asunto(s)
Colorantes/metabolismo , Hidrocarburos Policíclicos Aromáticos/metabolismo , Proteínas Bacterianas/metabolismo , Biodegradación Ambiental , Catálisis , Proteínas Fúngicas/metabolismo , Lacasa/metabolismo , Peroxidasas/metabolismo , Proteínas de Plantas/metabolismo , Eliminación de Residuos
10.
Water Sci Technol ; 79(1): 104-113, 2019 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-30816867

RESUMEN

The removal of microcystin-LR from aqueous solution using native Moringa oleifera Lam. seeds powder (MSP) and chemically pretreated M. oleifera Lam. seed powder (PMSP) was investigated in terms of equilibrium and kinetics. Optimum sorption conditions were determined as a function of pH (2-7), adsorbent dosage (0.25-1.0 g/L), initial concentration of microcystin-LR (15-120 mg/L) and contact time (15-360 minutes). The high values of regression constant, 0.98 (MSP) and 0.99 (PMSP), revealed that sorption of microcystin-LR was best fitted by the pseudo second order kinetic model. The equilibrium study was best fitted by the Freundlich model with both the adsorbents. The maximum sorption capacity by MSP and PMSP for microcystin-LR was 85.5 ± 1.1 mg/g and 92.49 ± 2.4 mg/g respectively. Fourier transform infrared spectroscopy showed the major involvement of carboxyl and hydroxyl groups for microcystin-LR sequestration either by complexation or ion exchange mechanism. The contribution of the adsorption phenomenon was confirmed by scanning electron microscopic analysis of microcystin-LR loaded and unloaded PMSP. Thus, the HCl-pretreated M. oleifera Lam. seed powder proved to be the pre-eminent biosorbent for removal of microcystin-LR from the wastewater stream.


Asunto(s)
Microcistinas/análisis , Moringa oleifera/química , Contaminantes Químicos del Agua/análisis , Purificación del Agua/métodos , Adsorción , Concentración de Iones de Hidrógeno , Cinética , Toxinas Marinas , Semillas , Espectroscopía Infrarroja por Transformada de Fourier
11.
Chem Cent J ; 11(1): 133, 2017 Dec 20.
Artículo en Inglés | MEDLINE | ID: mdl-29260332

RESUMEN

The present investigation aimed to study and compare the efficiency of non-viable fungal isolates to remove divalent lead (Pb(II)) from aqueous streams. The selected fungal isolates showed identity with Aspergillus caespitosus, Aureobasidium sp. RBSS-303 and Aspergillus flavus HF5 as confirmed using gene sequencing of ITS regions of the ribosomal DNA (rDNA). The obtained equilibrium data for Pb(II) biosorption of A. caespitosus fitted better to Langmuir isotherm with maximum sorption capacity of 351.0 mg/g and A. sp. RBSS-303 and A. flavus HF5 showed good fit to Freundlich isotherm with maximum sorption capacity of 271.5 and 346.3 mg/g respectively. The values of thermodynamic factors ascertained the nature of adsorption process is endothermic with A. caespitosus and A. flavus HF5 but exothermic with A. sp. RBSS-303. The experimental data for Pb(II) biosorption fits very well to pseudo second order kinetic model. With HCl the maximum 85.5, 75.3, 73.7% recovery of Pb(II) was obtained from A. caespitosus, A. sp. RBSS-303 and A. flavus HF5, respectively. The observed percentage loss in sorption capacity of Pb(II) was 3.9% by A. flavus HF5, 12.2% by A. caespitosus and 26.6% by A. sp. RBSS-303 after five cyclic studies of sorption and desorption. Results from the study confirmed the efficiency order of A. caespitosus > A. flavus HF5 > A. sp. RBSS-303 to remove and recover Pb(II) from aqueous solution. Finally, the fungal biosorbents can be used as soil conditioning agent after compositing into valuables fungal protein.

12.
J Photochem Photobiol B ; 175: 282-290, 2017 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-28923600

RESUMEN

Fungal biomass proves to be highly efficient for the treatment of wastewater as well as recovery of metal ions from wastewater. Present investigation was aimed to evaluate the efficiency of indigenous fungal isolates for the sequestration of Zn(II) ions aqueous solution. Among twenty five fungal isolates, Aspergillus oryzae SV/09 (AO SV/09), Aspergillus flavus NA9 (AF NA9) and Paecilomyces formosus DTO 63f4 (PF DTO-63f4) were identified by gene sequencing of ITS regions of the ribosomal DNA (rDNA). The AO SV/09, AF NA9 and PF DTO-63f4 showed promising efficiency for the biosorption of Zn(II) ions. Zn(II) ions adsorption was endothermic in nature and data fitted will to the Freundlich isotherm with correlation coefficients values of 0.99, 0.98 and 0.99 for AO SV/09, AF NA9 and PF DTO-63f4, respectively. Pseudo-second order kinetic model explained well the Zn(II) adsorption kinetic of Zn(II) ions onto biosorbents. The adsorbed Zn(II) ions were desorbed using HCl and 85.5, 75.3, 73.7 (%) Zn(II) ions were recovered from AO SV/09, AF NA9 and PF DTO-63f4 sorbents, respectively. The fungal biosorbents were successfully recycled up to five cycles. Based on sorption, recovery and regeneration, the application of fungal bio-sorbents for the sequestration and recovery of Zn(II) ions is suggested from wastewater and could possibly be extended for the recovery of other heavy metal ions from wastewater.


Asunto(s)
Aspergillus flavus/metabolismo , Aspergillus oryzae/metabolismo , Paecilomyces/metabolismo , Contaminantes Químicos del Agua/química , Zinc/química , Adsorción , Aspergillus flavus/genética , Aspergillus flavus/aislamiento & purificación , Aspergillus oryzae/genética , Aspergillus oryzae/aislamiento & purificación , Biomasa , ADN Ribosómico/química , ADN Ribosómico/genética , Concentración de Iones de Hidrógeno , Iones/química , Cinética , Paecilomyces/genética , Paecilomyces/aislamiento & purificación , Análisis de Secuencia de ADN , Temperatura , Termodinámica , Contaminantes Químicos del Agua/aislamiento & purificación , Zinc/aislamiento & purificación
13.
Pak J Pharm Sci ; 29(2): 423-8, 2016 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-27087070

RESUMEN

Benzamides and tryptamine are biologically significant compounds, therefore, various benzamide analogous of tryptamine have been efficiently synthesized using tryptamine and different benzoyl chlorides, in order to find new biologically active compounds. The resulting products were then characterized by melting point determination, calculation of Rf values and LC-MS techniques. At last, structure activity relationship (SAR) of the synthesized compounds was evaluated against two microbial strains; Bacillus subtilis and Aspergillus niger. All the five prepared products have shown high yield, sharp characterization and significant resistance against the growth of tested microorganism, providing a new range of tryptamine based benzamide derivatives having significant antimicrobial activities.


Asunto(s)
Antiinfecciosos/síntesis química , Antiinfecciosos/farmacología , Benzamidas/síntesis química , Benzamidas/farmacología , Triptaminas/síntesis química , Triptaminas/farmacología , Aspergillus niger/efectos de los fármacos , Aspergillus niger/crecimiento & desarrollo , Bacillus subtilis/efectos de los fármacos , Bacillus subtilis/crecimiento & desarrollo , Cromatografía Liquida , Espectrometría de Masas , Pruebas de Sensibilidad Microbiana , Estructura Molecular , Relación Estructura-Actividad , Temperatura de Transición
14.
Water Sci Technol ; 71(1): 139-48, 2015.
Artículo en Inglés | MEDLINE | ID: mdl-25607681

RESUMEN

The objective of this study was to assess the removal and recovery of Pb-II from industrial wastewater using a locally isolated strain of Aureobasidium sp. RBSS-303. The initial Pb2+ concentration of 600 mg/L resulted in maximum uptake capacity (Qmax 235.1±0.3 mg/g). The biosorbent revival was attained by contacting with HCl (0.01 M), with 75.3% recovery of Pb2+. The Freundlich isotherm best explains the Pb2+ sorption performances. Maximum adsorption distribution coefficient of 1,309.6 mg metal/mL was observed at initial Pb2+ concentration value of 100 mg/L. Evaluation of nine kinetic models showed the removal rate of Pb2+ was reliant on diffusion control pseudo-second-order and saturation-mixed-order kinetic models with a high correlation coefficient value (R=0.99). Fourier transform infrared spectroscopy analysis showed the major contribution of -NH2 and -CN ligands of Aureobasidium sp. RBSS-303 in the sorption phenomenon of Pb2+. The biosorption assays carried out with effluent of the paint industry showed 76.8% efficiency for Pb2+ removal by the candidate biosorbent, regardless of the complex composition of the industrial effluent.


Asunto(s)
Ascomicetos/metabolismo , Plomo/metabolismo , Eliminación de Residuos Líquidos/métodos , Contaminantes Químicos del Agua/metabolismo , Residuos Industriales/análisis
18.
Water Res ; 47(13): 4238-46, 2013 Sep 01.
Artículo en Inglés | MEDLINE | ID: mdl-23764574

RESUMEN

Zinc biosorption characteristic of locally isolated Aspergillus flavus NA9 were examined as a function of pH, temperature, pulp density, contact time and initial metal ion concentration. The maximum zinc uptake was found to be 287.8 ± 11.1 mg g(-1) with initial metal concentration 600 mg L(-1) at initial pH 5.0 and temperature 30 °C. The equilibrium data gave good fits to Freundlich and Florry models with correlation coefficient value of 0.98. The contribution of the functional groups and lipids to zinc biosorption as identified by chemical pretreatment was in the order: carboxylic acids > hydroxyl > amines > lipids. The mechanism of biosorption was also studied using Fourier transform infrared (FTIR) spectrometry, scanning electron microscopy (SEM) and energy dispersive X-ray analysis (EDX). The biosorbent was regenerated using 0.01 M HCl with 83.3% elution efficiency and was reused for five sorption-desorption cycles with 23.5% loss in biosorption capacity. The order of co-cations showing increased inhibitions of zinc uptake by A. flavus NA9 was Pb > Cu > Mn > Ni. The biosorption assays conducted with actual paint industry effluents revealed efficiency of 88.7% for Zn (II) removal by candidate biomass.


Asunto(s)
Aspergillus flavus/metabolismo , Residuos Industriales/análisis , Eliminación de Residuos Líquidos , Contaminantes Químicos del Agua/aislamiento & purificación , Zinc/aislamiento & purificación , Adsorción , Aspergillus flavus/ultraestructura , Biodegradación Ambiental , Biomasa , Cationes , Difusión , Concentración de Iones de Hidrógeno , Cinética , Microscopía Electrónica de Rastreo , Pintura , Espectrometría por Rayos X , Espectroscopía Infrarroja por Transformada de Fourier , Temperatura , Aguas Residuales/química
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