Cunninghamella echinulata a new biosorbent of metal ions from polluted water in Egypt

Thirty-two fungal species were isolated from a polluted watercourse near the Talkha fertilizer plant, Mansoura Province, Egypt. Aspergillus niger, A. flavus, Cunninghamella echinulata and Trichoderma koningii were isolated frequently. On the basis of its frequency, Cunninghamella echinulata was chosen for biosorption studies. Free and immobilized biomass of C. echinulata sequestered ions in this decreasing sequence is: Pb >Cu >Zn. The effects of biomass concentration, pH and time of contact were investigated. The level of ion uptake rose with increasing biomass. The maximum uptake for lead (45 mg/g), copper (20 mg/g) and zinc (18.8 mg/g) occurred at 200 mg/L biomass. The uptake rose with increasing pH up to 4 in the case of Pb and 5 in the case of Cu and Zn. Maximum uptake for all metals was achieved after 15 min. Ion uptake followed the Langmuir adsorption model, permitting the calculation of maximum uptake and affinity coefficients. Treatment of C. echinulata biomass with NaOH improved biosorbent capacity, as did immobilization with alginate. Immobilized biomass could be regenerated readily by treatment with dilute HCl. The biomass-alginate complex efficiently removed Pb, Zn and Cu from polluted water samples. Therefore,Cunninghamella echinulata could be employed either in free or immobilized form as a biosorbent of metal ions in waste water.     

Biosorption of cadmium by biomass of marine algae

Biomass of nonliving, dried brown marine algae Sargassum natans, Fucus vesiculosus, and Ascophyllum nodosum demonstrated high equilibrium uptake of cadmium from aqueous solutions. The metal uptake of cadmium from aqueous solutions. The metal uptake by these materials was quantitatively evaluated using sorption isotherms. Biomass of A. nodosum accumulated the highest amount of cadmium exceeding 100 mg Cd(2+)/g (at the residual concentration of 100 mg Cd/L and pH 3.5), outperforming a commercial ion exchange resin DUOLITE GT-73. A new biosorbent material based on A. nodosum biomass was obtained by reinforcing the algal biomass by formaldehyde cross-linking. The prepared sorbent possessed good mechanical properties, chemical stability of the cell wall polysaccharides and low swelling volume. Desorption of deposited cadmium with 0.1-0.5M HCI resulted in no changes of the biosorbent metal uptake capacity through five subsequent adsorption/desorption cycles. There was no damage to the biosorbent which retained its macroscopic appearance and performance in repeated metal uptake/elution cycles. (c) 1993 Wiley & Sons, Inc.     

Kinetics of biosorption of cadmium on Baker's yeast

In the present study the kinetics of biosorption of cadmium(II) ions by deactivated protonated yeast converted to sodium form was investigated for different initial concentrations of the metal ion (10-100 ppm) and different sorbent dosages (0.1-2.0 g) at a pH of 6.5. The adsorption process occurred in four distinct steps and the rates for these steps decreased sequentially. The rate of cadmium uptake in each case was pseudo-second-order with respect to metal ion concentration. The amount sorbed at equilibrium was found to be directly proportional to the initial metal ion concentration divided by the sorbent mass.     

Biotechnological potential of Chlorella vulgaris for accumulation of Cu and Ni from single and binary metal solutions

This study provides information on the mechanism(s) of Cu and Ni ion biosorption by C. vulgaris, distinguishing adsorption from intracellular accumulation under various conditions. Surface adsorption was found to contribute maximally (>70%) to total Cu/Ni ion accumulation by the test alga (total accumulation efficiencies were 60 and 53 g metal ion mg protein^–1, respectively for Cu and Ni). Maximum intracellular uptake was reported at a pH range of 6.5–7.5, whereas adsorption reached its maximum at pH 3.5 for Cu, and pH 3.5 and 6.5 in the case of Ni. 35 °C was found to be the best temperature for maximum adsorption, whereas intracellular uptake was highest at 25 °C. Though exponentially grown C. vulgaris registered maximum metal ion uptake, adsorption maxima reached the highest values in the declining phase of the culture. Heat-killed and air-dried C. vulgaris accumulated Cu and Ni at about 80% of the values for viable samples, whereas formaldehyde-treated and immobilized biomasses depicted better accumulating potential than the control cells. Na, K, Mn and Zn caused competitive inhibition, whereas for Ca a mixed-type inhibition was evident. Thus, the present study suggests that the general concept that cations inhibit metal ion accumulation by competing with them for the same binding sites on the cell surface is not absolutely valid. As these results also demonstrate that a large amount of the bound metal (>70%) is in the adsorbed fraction, it is advantageous in the sense that it could be recovered by a suitable desorbing agent, especially in case of precious metals and the biomass could be exploited for repeated use in reactors.     

Biosorption of mercury by the inactivated cells of pseudomonas aeruginosa PU21 (Rip64)

Biomass of a mercury-resistant strain Pseudomonas aeruginosa PU21 (Rip64) and hydrogen-form cation exchange resin (AG 50W-X8) were investigated for their ability to adsorb mercury. The maximum adsorption capacity was approximately 180 mg Hg/g dry cell in deionized water and 400 mg Hg/g dry cell in sodium phosphate solution at pH 7.4, higher than the maximum mercury uptake capacity in the cation exchange resin (100 mg Hg/g dry resin in deionized water). The mercury selectivity of the biomass over sodium ions was evaluated when 50 mM and 150 mM of Na(+) were present. Biosorption of mercury was also examined in sodium phosphate solution andphosphate-buffered saline solution (pH 7.0), containing 50mM and 150 mM of Na(+), respectively. It was found that the presence of Na(+) did not severely affect the biosorption of Hg(2+), indicating a high mercury selectivity ofthe biomass over sodium ions. In contrast, the mercury uptake by the ion exchange resin was strongly inhibited by high sodium concentrations. The mercury biosorption was most favorable in sodium phosphate solution (pH 7.4), with a more than twofold increase in the maximum mercury uptake capacity. The pH was found to affect the adsorption of Hg(2+)bythe biomass and the optimal pH value was approximately 7.4. The adsorption of mercury on the biomass and the ion exchange resin appeared to follow theLangmuir or Freundlich adsorption isotherms. (c) 1994 John Wiley & Sons, Inc.     

Removal of copper ions by the filamentous fungus, Rhizopus oryzae from aqueous solution

Removal of heavy metals present in wastewaters has been a major concern due to their non-biodegradability and toxicity. Removal of copper ion using NaOH treated Rhizopus oryzae biomass was investigated in a batch reactor. The copper uptake exhibited substantial enhancement both in terms of kinetics of uptake as well as the loading capacity. The copper biosorption by viable and pretreated fungal biomass fit well to a Lagergren's pseudo second order reaction in comparison to pseudo first order kinetics. Investigation on effect of pH indicated improved performance in the range of pH 4-6 in alkali treated biomass. Copper uptake exhibited by viable biomass was highest at 21 degrees C, unlike pretreated biomass that showed maximum uptake across the range of temperature 21-55 degrees C. The maximum copper loading capacity of the viable and pretreated biomass according to Langmuir isotherm was 19.4 and 43.7 mg/g, respectively. Distribution coefficient of pretreated biomass showed improvement at lower residual concentration, indicating a change in the nature of binding by the treated biomass. Copper uptake decreased with an increasing dose of biosorbent, although enhancement in the total metal ion removal was observed at higher dose.     

Cd (II) stress response during the growth of Aspergillus niger B 77

Aims:  To investigate the relationship between growth, heavy metal ions uptake and participation of the antioxidant enzymes superoxide dismutase (SOD) and catalase (CAT) in the protection of Apergillus niger B 77 against cadmium stress.
Methods and Results:  The stress response of the model fungal strain, under conditions of a wide range of Cd (II) ion concentrations, was investigated by determining the biomass formation, protein biosynthesis, SOD and CAT activities and heavy metal uptake in growing cells. Exposure to heavy metal ions induced an increase in protein content, heavy metal uptake and SOD activity, and a heavy decrease in CAT activity.
Conclusion:  The results obtained indicated that the tolerance of A. niger to Cd (II) was correlated with the heavy metal uptake, reactive oxygen species generation in the cells and the efficiency of antioxidative defence system.
Significance and Impact of the Study:  Evidence is provided for the possibility that oxidative stress plays a major role in the effect of Cd (II) ions on A. niger . These data could offer useful information when creating new strategies and methodological improvements for bioremediation with the participation of fungi.     

A comparative study on heavy metal biosorption characteristics of some algae

The biosorption of copper(II), nickel(II) and chromium(VI) from aqueous solutions on dried (Chlorella vulgaris, Scenedesmus obliquus and Synechocystis sp.) algae were tested under laboratory conditions as a function of pH, initial metal ion and biomass concentrations. Optimum adsorption pH values of copper(II), nickel(II) and chromium(VI) were determined as 5.0, 4.5 and 2.0. respectively, for all three algae. At the optimal conditions, metal ion uptake increased with initial metal ion concentration up to 250 mg l⁻¹. Experimental results also showed the influence of the alga concentration on the metal uptake for all the species. Both the Freundlich and Langmuir adsorption models were suitable for describing the short-term biosorption of copper(II), nickel(II) and chromium(VI) by all the algal species.     

Biosorption of Copper(II) by Live and Dried Biomass of the White Rot Fungi Phanerochaete chrysosporium and Funalia trogii

Biosorption is an innovative and alternative technology to remove heavy metal pollutants from aqueous solution using live, inactive and dead biomasses such as algae, bacteria and fungi. In this study, live and dried biomass of Phanerochaete chrysosporium and Funalia trogii was applied as heavy metal adsorbent material. Biosorption of copper(II) cations in aqueous solution by live and dried biomass of Phanerochaete chrysosporium and Funalia trogii was investigated to study the effects of initial heavy metal concentration, pH, temperature, contact time, agitation rate and amount of fungus. Copper(II) was taken up quickly by fungal biomass (live or dried) during the first 15 min and the most important factor which affected the copper adsorption by live and dried biomass was the pH value. An initial pH of around 5.0 allowed for an optimum adsorption performance. Live biomass of two white rot fungi showed a high copper adsorption capacity compared with dried biomass. Copper(II) uptake was found to be independent of temperature in the range of 20–45 °C. The initial metal ion concentration (10–300 mg/L) significantly influenced the biosorption capacity of these fungi. The results indicate that a biosorption as high as 40–60 % by live and dried biomass can be obtained under optimum conditions.     

Comparison of biosorption properties of different kinds of fungi for the removal of Gryfalan Black RL metal-complex dye

Three kinds of filamentous fungi (Rhizopus arrhizus, Trametes versicolor, Aspergillus niger) were tested for their ability to adsorb Gryfalan Black RL metal-complex dye as a function of pH, temperature and dye concentration. R. arrhizus and T. versicolor exhibited the maximum dye uptake at pH 2.0 and at 25 degrees C while A. niger performed the highest dye biosorption at pH 1.0 and at 35 degrees C. Sorption capacity of each biosorbent increased with increasing initial dye concentration. Among the three fungi, R. arrhizus was the most effective biosorbent showing a maximum dye uptake of 666.7 mg g(-1). The Langmuir model described the equilibrium data of each dye-fungus system accurately in the concentration and temperature ranges studied. Kinetic analysis indicated that both adsorption kinetics and internal diffusion played an important role on controlling the overall adsorption rate for each fungus. Thermodynamic analysis verified that A. niger biosorption was endothermic while the others were exothermic.     

Cadmium biosorption by Streptomyces pimprina waste biomass

Biosorption of cadmium from solution was studied using a hamycin-producing Streptomyces pimprina waste biomass. Mycelial pretreatments with 80% ethanol increased the uptake of cadmium threefold. The rate of uptake of the metal was maximum in the first 10 min and the equilibration of the system was achieved after 60 min. At pH 2.0 there was no adsorption of cadmium; however, as the pH of the solution increased, a rise in the adsorption could be noticed, which peaked at pH 5.0. The uptake of cadmium was found to increase linearly as a function of cadmium concentration up to 500 mg/l. The data could be fitted to Freundlich and Langmuir models for absorption processes. A 0.1 M EDTA solution could desorb cadmium loaded on S. pimprina biomass with the highest efficiency.     

Biosorption of lead(II), cadmium(II), copper(II) and nickel(II) by anaerobic granular biomass

Biosorption is potentially an attractive technology for treatment of wastewater for retaining heavy metals from dilute solutions. This study investigated the feasibility of anaerobic granules as a novel type of biosorbent, for lead, copper, cadmium, and nickel removal from aqueous solutions. Anaerobic sludge supplied from a wastewater treatment plant in the province of Quebec was used. Anaerobic granules are microbial aggregates with a strong, compact and porous structure and excellent settling ability. After treatment of the biomass with Ca ions, the cation exchange capacity of the biomass was approximately 111 meq/100 g of biomass dry weight which is comparable to the metal binding capacities of commercial ion exchange resins. This work investigated the equilibrium, batch dynamics for the biosorption process. Binding capacity experiments using viable biomass revealed a higher value than those for nonviable biomass. Binding capacity experiments using non-viable biomass treated with Ca revealed a high value of metals uptake. The solution initial pH value affected metal sorption. Over the pH range of 4.0-5.5, pH-related effects were not significant. Meanwhile, at lower pH values the uptake capacity decreased. Time dependency experiments for the metal ions uptake showed that adsorption equilibrium was reached almost 30 min after metal addition. It was found that the q(max) for Pb2+, Cd2+, Cu2+, and Ni2+ ions, were 255, 60, 55, and 26 mg/g respectively (1.23, 0.53, 0.87, and 0.44 mmol/g respectively). The data pertaining to the sorption dependence upon metal ion concentration could be fitted to a Langmiur isotherm model. Based on the results, the anaerobic granules treated with Ca appear to be a promising biosorbent for removal of heavy metals from wastewater due to its optimal uptake of heavy metals, its particulate shape, compact porous structure, excellent settling ability, and its high mechanical strength.     

白腐真菌吸附铅的研究

含重金属废水的传统处理方法有化学沉淀法、离子交换法、吸附法、电解法和膜分离法等,它们虽然也能达到一定的净化效果,但因过程繁琐并易造成二次污染而不够理想,尤其是金属离子浓度较低时,往往操作费用和原材料成本相对过高。近年来采用生物吸附法去除废水中的重金属...     

Biosorptive removal of cadmium from contaminated groundwater and industrial effluents

The cadmium removing capacity of a biosorbent Calotropis procera, a perennial wild plant, is reported here. The biomass was found to possess high uptake capacity of Cd(II). Adsorption was pH dependent and the maximum removal was obtained at two different pH i.e. pH 5.0 and 8.0. Maximum biosorption capacity in batch and column mode was found to be 40 and 50.5 mg/g. The adsorption equilibrium (> or =90% removal) was attained within 5 min irrespective of the cadmium ion concentration. Interfering ions viz. Zn(II), As(III), Fe(II), Ni(II) interfered only when their concentration was higher than the equimolar ratio. The Freundlich isotherm best explained the adsorption, yet the monolayer adsorption was also noted at lower concentrations of Cd(II). The FTIR analysis indicates the involvement of hydroxyl (-OH), alkanes (-CH), nitrite (-NO(2)), and carboxyl group (-COO) chelates in metal binding. The complete desorption of the cadmium was achieved by 0.1M H(2)SO(4) and 0.1M HCl. The C. procera based Cd(II) removal technology appears feasible.     

Copper biosorption by Auricularia polytricha

AIMS: The objective of the present study was to determine the optimum conditions for copper (Cu) biosorption by Auricularia polytricha mycelium in view of its immobilization in polyvinyl alcohol (PVA). METHODS AND RESULTS: The adsorption of Cu(II) onto A. polytricha was studied in batch with respect to initial pH, temperature, adsorption time, initial metal ion and biomass concentration. At optimal adsorption conditions, biomass was immobilized in PVA in column and a biosorption capacity of about 90% was obtained. CONCLUSIONS: Auricularia polytricha strain could successfully be used as Cu biosorbent. SIGNIFICANCE AND IMPACT OF THE STUDY: The low cost and simplicity of the technique make it suitable for the detoxification of contaminated effluents before their environmental discharge.     

Biosorption of nickel(II) ions by baker's yeast: kinetic, thermodynamic and desorption studies

In this study, the biosorption of nickel(II) ion on deactivated protonated yeast was investigated as a function of temperature at different initial metal ion concentrations. The effect of temperature on the sorption was more significant at lower nickel(II) ion concentrations compared to higher concentrations. The protonated yeast biomass exhibited the highest nickel(II) ion uptake capacity at 27 degrees C at an initial nickel(II) ion concentration of 400mg/l and an initial pH of 6.75. The biosorption capacity decreased from 9.8 to 9.3mg/g at an initial nickel(II) ion concentration of 400mg/l, while at a lower initial concentration of 100mg/l, it decreased from 8.2 to 4.9 mg/g, as the temperature was increased from 27 degrees C to 60 degrees C. The equilibrium data fit better to the Freundlich and Redlich-Peterson isotherm models compared to the Langmuir model in the concentration range studied (10-400mg/l). Kinetic models applied to the sorption data at different temperatures showed that nickel(II) ion uptake process followed the pseudo-second order rate model and the adsorption rate constants decreased with increasing temperature. The activation energy of biosorption (Ea) was determined to be -13.3 kJ/mol using the pseudo-second order rate constants. The results indicated that the biosorption of nickel(II) ion on to baker's yeast was spontaneous and exothermic in nature. Desorption studies revealed that the protonated yeast biomass can be regenerated using 0.1N HCl and reused.     

Cyanobacteria as a biosorbent for mercuric ion

The biosorption of Hg(2+) by two strains of cyanobacteria, Spirulina platensis and Aphanothece flocculosa, was studied under a batch stirred reaction system. Essential process parameters, including pH, biomass concentration, initial metal concentration, and presence of co-ions were shown to influence the Hg(2+) uptake. Hg(2+) uptake was optimal at pH 6.0 for both strains. The maximum loading capacities per gram of dry biomass were found to be 456 mg Hg(2+) for A. flocculosa and 428 mg Hg(2+) for S. platensis. At an initial concentration of 10 ppm Hg(2+), A. flocculosa was able to remove more than 98% of the mercury ion from solution. The biosorption kinetics of both strains showed that the metal uptake is bi-phasic, exhibiting a rapid initial uptake followed by a slower absorption process. The presence of dissolved Co(2+), Ni(2+), and Fe(3+) were found to play a synergistic role for Hg(2+) uptake by both strains. Regeneration of the biomass was examined by treating Hg(2+)-loaded samples with HCl and NH(4)Cl over four cycles of sorption and desorption.     

Potential capacity of Beauveria bassiana and Metarhizium anisopliae in the biosorption of Cd2+ and Pb2+

In this study Beauveria bassiana and Metarhizium anisopliae were used as inexpensive and efficient biosorbents for Pb(II) and Cd(II) from aqueous metal solutions. The effects of various physicochemical factors on Pb(II) and Cd(II) biosorption by B. bassiana and M. anisopliae were studied. The optimum pH for Cd(II) and Pb(II) biosorption by two fungal species was achieved at pH 6.0 for Pb(II) and 5.0 Cd(II) at a constant time of 30 min. The nature of fungal biomass and metal ion interactions was evaluated by Fourier transform infrared. The maximum adsorption capacities (q(max)) calculated from Langmuir isotherms for Pb(II), and Cd(II) uptake by B. bassiana were 83.33±0.85, and 46.27±0.12 mg/g, respectively. However, the q(max) obtained for Pb(II) uptake by M. anisopliae was 66.66±0.28 mg/g, and 44.22±0.13 mg/g for Cd(II). B. bassiana showed higher adsorption capacity compared to M. anisopliae. The data obtained imply the potential role of B. bassiana and M. anisopliae for heavy metal removal from aqueous solutions.     

Removal of lead from aqueous solutions by Penicillium biomass

The removal of lead ions from aqueous solutions by adsorption on nonliving Penicillium chrysogenum biomass was studied. Biosorption of the Pb(+2) ion was strongly affected by pH. Within a pH range of 4 to 5, the saturated sorption uptake of Pb(+2) was 116 mg/g dry biomass, higher than that of activated charcoal and some other microorganisms. At pH 4.5, P. chrysogenum biomass exhibited selectivity for Pb(+2) over other metal ions such as Cd(+2), Cu(+2), Zn(+2), and As(+3) Sorption preference for metals decreased in the following order: Pb > Cd > Cu > Zn > As. The sorption uptake of Pb(+2) remained unchanged in the presence of Cu(+2) and As(+3), it decreased in the presence of Zn(+2), and increased in the presence of Cd(+2). (c) 1993 John Wiley & Sons, Inc.