Dead Fungal Biomass Research Articles

Biosorption of methylene blue from aqueous solution by nonviable Aspergillus fumigatus

The main objective of this work was to study the possibility of improving the biosorption of textile dye basic model, methylene blue (MB) by dead fungal biomass, Aspergillus fumigatus. For an initial concentration of MB (5mg/L) and under proved optimal conditions (pH 7 and 30°C), the equilibrium was reached after 90min. A chemical pretreatment of A. fumigatus with NaClO 4 °Chl (chlorometric degrees), H2O2 30%, CaCl2 0.1M, SDS 1mM, NaOH 0.1M, NaHCO3 0.1M; the physical pre-treatment by autoclaving and adding SDS 1mM, NaCl 1mM to the MB solutions have allowed a considerable and very significant improvement of MB biosorption. However the chemical pretreatment with a solution of H2SO4 0.1M, and the addition of PbCl2 0.1M have lead to lower capacity of biosorption. The maximum biosorption capacity was 125mg/g. The desorption studies were conducted by changing of the pH value among 3–10. The maximum desorption percentage of MB was found to be 80% at pH 3. The modeling of the experimental data at equilibrium was performed with Langmuir, Freundlich, Langmuir–Freundlich, Dubinin Radushkevich (D–R) and Temkin isotherms. The result has shown that the biosorption was favorable, physicochemical in nature and agree well with Langmuir and Freundlich models, with correlation coefficients close to 1.00 in both cases.

Computational Identification and Analysis of the Key Biosorbent Characteristics for the Biosorption Process of Reactive Black 5 onto Fungal Biomass

The performances of nine biosorbents derived from dead fungal biomass were investigated for their ability to remove Reactive Black 5 from aqueous solution. The biosorption data for removal of Reactive Black 5 were readily modeled using the Langmuir adsorption isotherm. Kinetic analysis based on both pseudo-second-order and Weber-Morris models indicated intraparticle diffusion was the rate limiting step for biosorption of Reactive Black 5 on to the biosorbents. Sorption capacities of the biosorbents were not correlated with the initial biosorption rates. Sensitivity analysis of the factors affecting biosorption examined by an artificial neural network model showed that pH was the most important parameter, explaining 22%, followed by nitrogen content of biosorbents (16%), initial dye concentration (15%) and carbon content of biosorbents (10%). The biosorption capacities were not proportional to surface areas of the sorbents, but were instead influenced by their chemical element composition. The main functional groups contributing to dye sorption were amine, carboxylic, and alcohol moieties. The data further suggest that differences in carbon and nitrogen contents of biosorbents may be used as a selection index for identifying effective biosorbents from dead fungal biomass.

Adsorption of heavy metal from landfill leachate by wasted biosolids

The adsorption capacity of wasted solids that contained dead fungal biomass (Phanerochaete chrysosporium) was studied to remove cadmium, copper, zinc and iron from synthetic water and leachate. The biomass was produced due to the experiments conducted for bioconversion of wastewater for lignin peroxydase production in the laboratory. In the screening experiments, the maximum cadmium (Cd) adsorption from synthetic water was 28.81% at 18 h. Meanwhile, adsorption of copper (Cu), zinc (Zn) and iron (Fe) reached maximum condition after 5 h with 41.29, 58.94 and 52.03% removal efficiency, respectively. However, the concentration of Cd, Cu and Zn was not detected in the leachate but Fe was found to be in high concentration (184 mg/L) in raw leachate collected from a municipal landfill site. Therefore, the effects of biomass dosage, contact time, pH and agitation speed were observed for optimal adsorption of iron from leachate. Optimum removal of iron from leachate was 45.56% in every 1 L of leachate after 1/50 dilutions. The optimized biomass dosage, contact time, pH and agitation speed were 750 mg/L, 4 h, pH 5, and 150 rpm, respectively. The results of this study indicated that the biomass generated from the laboratory experiments could be used, before discarding, to remove iron from leachate which is one of the main problems at the landfill sites.

Kinetics and equilibrium studies on biosorption of nickel from aqueous solution by dead fungal biomass of Mucor hiemalis

The kinetics and equilibrium of the biosorption of nickel from aqueous solution were investigated using physico-chemically treated dead biomass of Mucor hiemalis in a batch system. The biosorption characteristics of Ni (II) ions were studied with respect to well-established effective parameters including pH, temperature, rotational speed, biosorbent dosage, initial metal ion concentration and contact time. The uptake of Ni (II) increased with an increase in pH, the Ni (II) concentration, temperature and rotational speed, whereas it decreased with increase in the biomass concentration. Biosorption equilibrium was established in about 150 min. The Ni (II) adsorption data were analyzed using the first and the second-order kinetic models as well as intra-particular rate expressions. The second-order equation was the most appropriate equation to predict the biosorption capacities of the fungal preparation. The sorption data obtained at pH 8.0 conformed well to both the Langmuir and the Freundlich isotherm models. The reusability of the biosorbent was tested in five consecutive adsorption–desorption cycles and the regeneration efficiency was above 80%. From the practical viewpoint, the abundant and inexpensive dead fungal biomass could be used as an effective, low cost and environmentally friendly biosorbent for the detoxification of Ni (II) from aqueous solution.

Biosorptive uptake of cationic dyes from aqueous phase using immobilised dead macro fungal biomass

Present study deals with possible utilisation of immobilised biomass of a wood rotting dead macro fungus Fomitopsis carnea for the removal of cationic dyes from aqueous solution. The results indicated that biosorbent showed the highest affinity (Langmuir monolayer saturation capacity) for Safranin O (62.9 mg/g), followed by Neutral red (45.5 mg/g), Pyronin Y (30.6 mg/g), Malachite Green (29.9 mg/g), Thioflavine T (21.9 mg/g) and the lowest for Acriflavine (17.4 mg/g). The uptake of Safranin O was increased from 52.8 mg/g to 70.9 mg/g when temperature was increased from 20°C to 40°C. Increased uptake at high temperature suggests predomination of chemi-sorption and/or ion-exchange process. Safranin O uptake capacity of the biosorbent was decreased (from 87% to 74%) with increased in salt concentration (from 0 mM to 100 mM) indicating an ion-exchange type of dye-biosorption interaction could be possible. However, in case of increase in initial pH from 2 to 11, dye sorption also increased from 25% to 75%. This suggests possibility of electrostatic attraction between dye cation and biosorbent particle. Hydrochloric acid (0.1 M) could be used to regenerate the spent biosorbent.

Removal of Disperse Red 1 from an aqueous solution by fungus Aspergillus niger

In this study, removal of Disperse Red 1 from an aqueous solution by biosorption on dead fungus, Aspergillus niger was investigated. Effective pretreatment for increasing the biosorption capacity was studied by using different pretreatment methods. Among them, NaOH pretreatment was the most effective. The effective initial pH for the maximum dye adsorption by fungal biomass was 4.0. Kinetic studies showed that the biosorption of Disperse Red 1 on fungal biomass was a slow process and the binding between fungal biomass and the molecules of Disperse Red 1 was weak in the initial period. Equilibrium was reached in 48 h. Isotherm studies showed that the Redlich–Peterson isotherm model could describe the experimental data with a low correlation coefficient. This study demonstrated that dead fungal biomass of A. niger was only moderately effective in removing Disperse Red 1 from an aqueous solution.

Biosorption of uranium(VI) from aqueous solution by dead fungal biomass of Penicillium citrinum

The ability of non-living biomass of Penicillium citrinum has been explored for the removal and recovery of uranium from aqueous solutions. The biosorbent was characterized by SEM, EDS and FT-IR. The influences of different experimental parameters such as initial solution pH, initial uranium concentration, contact time, biomass dosage and temperature on adsorption were investigated. The P. citrinum exhibited the highest uranium sorption capacity at an initial pH of 6.0 and at 5 h. Biosorption capacity increased from 103.1 to 127.3 mg g −1 with an increase in temperature from 298 to 318 K at an initial uranium concentration of 50 μg/mL. Adsorption kinetics was better described by the pseudo-second-order model and adsorption process could be well defined by both the Langmuir and Freundlich isotherms, however, Freundlich isotherm displayed a better fitting model than Langmuir isotherm. The thermodynamic parameters: Δ G° (308 K), Δ H°, and ΔS° for sorption process were determined to be −20.48 kJ mol −1, 10.76 kJ mol −1, and 101.43 J mol −1 K −1, respectively. The results presented in this study showed that the P. citrinum offered great potential as a biosorbent to remove uranium ions from aqueous solutions.

Production of extracellular enzymes and degradation of biopolymers by saprotrophic microfungi from the upper layers of forest soil

Production of extracellular enzymes participating in the degradation of biopolymers was studied in 29 strains of nonbasidiomycetous microfungi isolated from Quercus petraea forest soil based on the frequency of occurrence. Most of the isolates were ascomycetes and belonged to the genera Acremonium, Alternaria, Cladosporium, Geomyces, Hypocrea, Myrothecium, Ochrocladosporium, and Penicillium (18 isolates), and two isolates were zygomycetes. Only six isolates showed phenol oxidation activity which was low and none of the strains were able to degrade humic acids. Approximately half of the strains were able to degrade cellulose and all but six degraded chitin. Most strains produced significant amounts of the cellulolytic enzymes cellobiohydrolase and β-glucosidase and the chitinolytic enzymes chitinase, chitobiosidase, and N-acetylglucosaminidase. The highest cellulase activities were found in Penicillium strains, and the highest activity of chitinolytic enzymes was found in Acremonium sp. The production of the hemicellulose-degrading enzymes α-galactosidase, β-galactosidase, and α-mannosidase was mostly low. The microfungal strains were able to produce significant growth on a range of 41–87, out of 95 simple C-containing substrates tested in a Biolog™ assay, monosaccharides being for all strains the most rapidly metabolized C-sources. Comparison with saprotrophic basidiomycetes from the same environment showed that microfungi have similar cellulolytic capabilities and higher chitinase activities which testifies for their active role in the decomposition of both lignocellulose and dead fungal biomass, important pools of soil carbon.

Photo-enhancement of Cr(VI) reduction by fungal biomass of Neurospora crassa

Various organisms such as fungus are capable of reducing Cr(VI) to less toxic Cr(III). However, light-induced Cr(VI) reduction by fungus is less reported and needs to be explored since anthropogenic or natural activities may bring these two reactants into a sunlit environment. In this study, the interactions and reaction mechanisms of Cr(VI) on a model fungus, Neurospora crassa, were evaluated in the presence or absence of light. The influence of ferric ion, a widely distributed metal, on Cr(VI) reduction by the fungus was also investigated under illumination. The results show that 20–54% of added Cr(VI) (96.2μM) was removed by 1g of dead fungal biomass (i.e., 1–2.7mg Cr(VI) reduction by 1g biomass) at pH 1–3, after 6h reaction in the dark. However, 96.2μM Cr(VI) disappeared completely (i.e., 5mg Cr(VI) reduction by 1g biomass) under the same reaction time and experimental conditions when light was present. The rapid disappearance of Cr(VI) in solution was due to the reduction of Cr(VI) by the excited biomass upon light absorption, and the rates of redox reactions increased with a decrease at pH. Cr(VI) reduction could be further increased with the addition of 89.5μM Fe(III) because the formation of Fe(II) from the photolysis of Fe–organic complexes enhanced Cr(VI) reduction. Spectroscopic studies indicated that the amide, NH, and carboxyl groups of N. c.-biomass may be responsible for initiating Cr(VI) reduction; comparatively, the cyclo-carbons of chitin, glucan, and their derivatives were more persistent to the oxidation by Cr(VI). Accordingly, fungi containing high amount of carboxyl, amide, and NH groups may be preferable as efficient reductants for scavenging Cr(VI) from environment. Upon the absorption of a renewable light source, Cr(VI) could be converted rapidly by the biomaterials to the less toxic Cr(III).

Biosorption of hexacyanoferrate(III) complex anion to dead biomass of the basidiomycete Pleurotus mutilus: Biosorbent characterization and batch experiments

This work is a contribution to the use of natural, cost-effective biosorbants in industrial wastewater treatment processes, addressing more particularly to the effluents resulting from surface treatment and mining industries. A dead fungal biomass (i.e., Pleurotus mutilus) collected as a waste from an antibiotic production plant was tested as a biosorbent for iron(III)–cyanide complex ions. A physicochemical characterization of this biomass was followed by batch biosorption experiments. Potentiometric titration confirmed by FTIR analysis indicated a variety of functionalities on the biomass surface, primarily carboxylic and amine groups which conferred to the biosorbent a positive charge in acid medium and a negative charge in alkaline medium. Biomass pre-treatment with acetic acid slightly improved its biosorption efficiency which was also affected by the initial pH of the test solution, the size and concentration of biosorbent particles, and the stirring speed of the particle suspension. In particular, the best performance was obtained at strongly alkaline pH (around 12) even though the overall electrical charge of the biomass was negative in this pH range. The sorption kinetics obeyed both pseudo-first-order and pseudo-second-order models and intraparticle diffusion was the main limiting step in the biosorption kinetics. Applying the Langmuir isotherm modelling, the highest biosorption efficiency, i.e., the maximum solid phase concentration of complex ions (forming a complete monolayer coverage on the sorbent surface) was over 620 mg g−1. Continuous fixed-bed sorption–desorption experiments are in progress to confirm these promising results.

Kinetics, equilibrium and thermodynamic studies on biosorption of hexavalent chromium by dead fungal biomass of marine Aspergillus niger

Abstract Quite a number of reports are available on metal binding capacity of different groups of microorganisms. However, reports on the equilibrium studies on biosorption by marine fungi are quite inadequate. The present study was carried out in a batch system using dead biomass of marine Aspergillus niger for the sorption of Cr(VI). The removal rate of Cr(VI) was increased with a decrease in pH and an increase in Cr(VI) and biomass concentration. A. niger exhibited the highest Cr(VI) uptake of 117.33 mg g−1 of biomass at pH 1.0 in the presence of 400 mg l−1 Cr at 50 °C. Kinetics studies based on fractional power, zero order, first order, pseudo-first order, Elovich, second order and pseudo-second order rate expressions have also been carried out. The experimental data were analyzed using five, two-parameter isotherms (Langmuir, Freundlich, Dubinin–Radushkevich, Temkin and Halsey). It was observed that Langmuir model exhibited the best fit to experimental data. Thermodynamic parameters of the biosorption (ΔG°, ΔH° and ΔS°) were also determined.

Hg(II) Removal from Aqueous Solution by Dead Fungal Biomass of Marine Aspergillus niger: Kinetic Studies

Mercury removal from wastewater is a recognized pollution control challenge today. In the present investigation, the biosorption of Hg(II) onto the dead biomass of four different species of marine Aspergillus, prepared by alkaline treatment, was studied. Among the cultures studied, A. niger was found to be the most efficient for Hg(II) removal. The effects of initial Hg(II) concentration, contact time, pH, temperature, and biosorbent dosage on biosorption were also investigated. It was observed that biosorption equilibriums were established in about 2 h. Under the optimum conditions (pH: 3.0, Hg(II) concentration: 250 mg/L, biomass dose: 0.8 g/L, temperature: 40°C and contact time: 2 h), 40.53 mg Hg(II) was biosorbed per gram of dead biomass of A. niger. Kinetic studies based on fractional power, zero order, first order, pseudo first order, Elovich, second order, and second order rate expressions have also been carried out where the pseudo second order model exhibited best fit to experimental data. The intra‐particle diffusion study revealed that film diffusion is the rate‐limiting sorption process for Hg(II) on A. niger. The nature of the possible cell–metal ion interactions was evaluated by FTIR, SEM, and EDAX analysis. These examinations indicated the involvement of ‐OH and ‐NH2 + groups in the biosorption process present on the surface of the dead fungal biomass. Here, Hg(II) ions were deposited on the surface of the biomass as a film like structure.

Biosorption of chromium(VI) from aqueous solution and electroplating wastewater using fungal biomass

Biosorption of Cr(VI) ions from aqueous solution as well as from electroplating effluent with dead fungal biomass sp. Aspergillus niger, Aspergillus sydoni and Penicillium janthinellum was investigated in the batch mode. The influence of pH of the solution, biosorbents dose, concentration of ions and contact time on biosorption capacity of Cr(VI) ions was studied. The optimum pH for biosorption of Cr(VI) ions was found to be 2.0. The removal of Cr(VI) was 91.03% with A. niger at biosorbent dose 0.6 g/50 mL, whereas, 87.95% and 86.61% with A. sydoni and P. janthinellum at biosorbent dose 0.8 g/50 mL but uptake capacity (mg/g) of Cr(VI) ions decreased with increased biosorbent dose. Initially percent removal of Cr(VI) ions from solution was increased with increase in concentration from 10 to 30 mg/L and maximum percent removal was observed at concentration 30 mg/L after that percent removal decreased. Whereas, uptake capacity was increased with increase in concentration of Cr(VI) ions from 10 to 60 mg/L. Uptake rate of Cr(VI) increased from 1.72 to 2.39 mg/g with A. niger, 1.22 to 1.76 mg/g with A. sydoni and 1.18 to 1.77 mg/g with P. janthinellum with increases time from 15 to 120 min. Removal of Cr(VI) from electroplating wastewater was observed less than from synthetic solution. Higher value of correlation coefficient (r2 > 0.90) indicates that adsorption data are best fitted in both Freundlich and Langmuir isotherms model. The high value of Freundlich constants Kf and n, i.e. 17.92 mg/g and 1.18 L/mg and Langmuir constants Q0 and b 17.61 mg/g and 0.0026 L/mg for A. niger indicate its better adsorption capacity than A. sydoni and P. janthinellum.

Biosorption of chromium from aqueous solutions by pretreated Aspergillus niger: Batch and column studies

This study involved the investigation of enhancement of chromium biosorption capacity of dead Aspergillus niger fungal biomass by pretreatment and its use in a column mode. Cetyl trimethyl ammonium bromide (CTAB) pretreatment exhibited maximum chromium removal. An initial factorial design of experiments showed that factors such as pH of the solution, temperature and biomass mass were important. The kinetics of biosorption of chromium was found to follow Ho pseudo-second order reaction. Isotherm studies conducted at 5 ± 2, 15 ± 2, 22 ± 2, and 30 ± 2 °C provided maximum biosorption capacities of 14.5, 15.2, 10.6, and 11.6 mg/g, respectively. The Freundlich isotherm model was found to describe biosorption. Thermodynamic studies indicated that the biosorption reaction was spontaneous and exothermic in nature. Reusability of biomass was examined by the desorption studies, in which NaOH eluted 90% chromium. Data from a column study using CTAB pretreated biomass immobilized in polysulfone matrix followed Yan's model and the adsorption capacity of the biomass was found to be less than the adsorption capacity obtained in the batch study. Fourier transform infrared spectroscopy analysis indicated that in addition to various functional groups present on the cell wall, the contribution of amino groups towards the biosorption process was evident.

Metal Biosorption Studies to Treat Combined Industrial Effluents Using P. chrysosporium

This work reports the treatability studies conducted on the combined industrial effluent sample by white rot fungus. The selected strain, Phanerochaete chrysosporium, a white rot fungus, was employed in reduction of toxic metals. The specific growth rate of the fungus was found to be in the range of 0.089-0.102 hr -1. Studies conducted on biosorption of metals showed that the dead fungal biomass was found to be more effective than living fungus. The optimum pH for the fungal growth was found to be at 4.5 but enhanced biosorption was at pH 6, especially for maximum reduction of hexavalent chromium to trivalent chromium. Laboratory-scale experiments for metal biosorption with this Basidiomycete showed encouraging results, which could be applied further to pilot tests and large-scale studies.

Biosorption of Combined Industrial Effluents using Phanerochaete Chrysosporium

The biosorption of eight different metals from aqueous solutions of combined industrial effluent by live or dead cells of Phanerochaete chrysosporium was investigated. Growth rate studies of P. chrysosporium were carried out in a selected medium as well as in the effluent. The specific growth rate of the fungus was in the range of 0.089–0.102 h–1 in the medium. The biosorption of metal ions increased as the initial concentration of metal ions increased in the medium. Biosorption equilibrium was established in about 1 h and the concentration of adsorbed metal ions did not change further with time. The equilibrium was well described by Langmuir, Freundlich and Reidlich – Peterson isotherms. The dead fungal biomass was more effective than living fungus for biosorption of metals. The optimum pH for the fungal growth was at 4.5 but enhanced Biosorption was at pH 6 for maximum reduction of hexavalent chromium to trivalent.

Adsorptive removal of textile dyes from aqueous solutions by dead fungal biomass

Dead fungal biomass prepared from Phanerochaete chrysosporium and Funalia trogii was tested for their efficiency in removal of textile dyes. The effects of contact time, initial dye concentration, amount of dead biomass and agitation rate on dye removal have been determined. Removal of all dyes required a very short time (60 min). Experimental results show that, P. chrysosporium was more effective than F. trogii . An increase in the amount of dead biomass positively affected of the dye removal. The removal efficiency of different amount of biomass was in order 1 g > 0.5 g > 0.2 g > 0.1 g. The highest removal was obtained at 150-200 rpm. Slightly lower removing activities were found at lower agitation rates. This study showed that it was possible to remove textile dyes by dead biomass of P. chrysosporium .

Adsorption isotherms of copper(II) for two species of dead fungi biomasses

A study of copper(II) adsorption equilibrium in aqueous solutions was made on dead fungal biomass of Pleurotus pulmonarius CCB019 and Schizophyllum commune in batch systems. A fractional factorial design 2 4−1 based in preliminary experiments (kinetic and precipitation studies) was made to verify the influence on the response variable of the four factors studied in adsorption process: pH (2.0 and 4.0), temperature (30 and 50 °C), initial metal concentration (4 and 100 mg l −1) and biomass concentration (0.5 and 3.0 g l −1). The response measured was the concentration of metal removed after a contact time of 12 h, with either the P. pulmonarius or the S. commune biomass. Based on results obtained from the fractional factorial design, the experimental conditions used in adsorption isotherm construction were: pH 4.0, temperature 50 °C, biomass concentration 3 g l −1. The initial metal concentration was varied between 5 and 200 mg l −1. The experimental data was best adjusted by Langmuir model for both biomass.

Use of dead fungal biomass for the detoxification of hexavalent chromium: screening and kinetics

The removal of hexavalent chromium from aqueous solution was carried out in batch experiments using dead biomass of four fungal strains – Aspergillus niger, Rhizopus oryzae, Saccharomyces cerevisiae and Penicillium chrysogenum. All of these dead fungal biomass completely removed Cr(VI) from aqueous solutions, that of R. oryzae being the most effective. Cr(VI) was removed from aqueous solutions by the reduction to Cr(III) when it contacted with the biomass. The removal rate of Cr(VI) increased with a decrease in pH or with increases of Cr(VI) and biomass concentrations. In particular, the removal rate of Cr(VI) was proportional to total chromate concentration [Cr(VI)], and equivalent concentration of organic compounds [OC], suggesting a simple rate equation in a form of d[Cr(VI)]/d t = − k[Cr(VI)][OC]. This model fitted well with the experimental data obtained at pH 2, supporting the mechanism that Cr(VI) is removed via a redox reaction. From the practical view point, the abundant and inexpensive dead fungal biomass could be used for the conversion of toxic Cr(VI) into less toxic or nontoxic Cr(III).

Mechanism of hexavalent chromium removal by dead fungal biomass of Aspergillus niger

When synthetic wastewater containing Cr(VI) was placed in contact with the dead fungal biomass of Aspergillus niger, the Cr(VI) was completely removed from aqueous solution, whereas Cr(III), which was not initially present, appeared in aqueous solution. Desorption and X-ray photoelectron spectroscopy (XPS) studies showed that most of the Cr bound on the biomass was in trivalent form. These results indicated that the main mechanism of Cr(VI) removal was a redox reaction between Cr(VI) and the dead fungal biomass, which is quite different from previously reported mechanisms. The influences of contact time, pH, Cr(VI) concentration, biomass concentration and temperature on Cr(VI) removal were also evaluated. The Cr(VI) removal rate increased with a decrease in pH and with increases in Cr(VI) concentration, biomass concentration and temperature. Although removal kinetics was dependent on the experimental conditions, Cr(VI) was completely removed in the aqueous solution. In conclusion, a new mechanism of Cr(VI) removal by the dead fungal biomass has been proposed. From a practical viewpoint, this abundant and inexpensive dead fungal biomass has potential application in the conversion of toxic Cr(VI) into less toxic or nontoxic Cr(III).