Abstract
Chromium Cr(VI) is a highly toxic environmental contaminant for any organism, its presence in the environment is mainly due to anthropogenic activities. The use of biotechnology has been implemented for the treatment of effluents contaminated with Cr(VI).Our working group has isolated several fungi and bacteria capable of removing Cr(VI) from the culture medium. Aspergillus niger var tubingensis Ed8 is a strain that can produce metabolites which reduce Cr (VI) to Cr (III). The objective of this work was to determine the effect of sodium salicylate on the growth of this strain and on the Cr(VI) reduction system, as well as to identify the metabolites that are produced from sodium salicylate. Our results show that the Culture medium containing sodium salicylate (20 mM) inhibits strain growth compared to the control condition (0 mM). However, it increases the specific reduction capacity of Cr (VI) red/mg Biomass in order of magnitude. Analysis of the culture medium corresponding to 48 h of incubation shows the presence of catechol and salicylate diminution. In addition, as a product of the enzymatic activity of a cell-free cellular extract, after 24 h of incubation, the consumption of salicylate is detected, as well as the presence of peaks corresponding to resorcinol and catechol. Our results show that it is possible to increase the Cr(VI) reducing capacity of the Ed8 strain, depending on the composition of the culture medium.
Acknowledgments
The authors are highly grateful to DCNE, Universidad de Guanajuato, Ph.D. Francisco Acevedo Aguilar and Ph.D. Kazimierz Wrobel for providing the necessary support and research facilities. IN MEMORIA TO Ph.D. MARIANO GUTIERREZ ROJAS.
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Author contributions: All the authors have accepted responsibility for the entire content of this submitted manuscript and approved submission.
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Research funding: None declared.
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Conflict of interest statement: The authors declare no conflicts of interest regarding this article.
References
Acevedo-Aguilar, F. J., A. E. Espino-Saldaña, I. L. León-Rodríguez, M. Ávila-Rodríguez, K. Wrobel, K. Wrobel, P. Lappe, M. Ulloa, and J. F. Gutiérrez-Corona. 2006. “Hexavalent Chromium Removal In Vitro and from Industrial Wastes, Using Chromate-Resistant Strains of Filamentous Fungi Indigenous to Contaminated Wastes.” Canadian Journal of Microbiology 52 (9): 809–15, https://doi.org/10.1139/w06-037.Search in Google Scholar PubMed
Ackerley, D. F., C. F. Gonzalez, C. H. Park, R. Blake, M. Keyhan, and A. Matin. 2004. “Chromate-reducing Properties of Soluble Flavoproteins from Pseudomonas putida and Escherichia coli.” Applied and Environmental Microbiology 70: 873–82, https://doi.org/10.1128/aem.70.2.873-882.2004.Search in Google Scholar
Adhoum, N., L. Monser, N. Bellakhal, and J. E. Belgaied. 2004. “Treatment of Electroplating Wastewater Containing Cu2+, Zn2+ and Cr (VI) by Electrocoagulation.” Journal of Hazardous Materials 112 (3): 207–13, https://doi.org/10.1016/j.jhazmat.2004.04.018.Search in Google Scholar PubMed
Al-Battashi, H., S. J. Joshi, B. Pracejus, and A. Al-Ansari. 2016. “The Geomicrobiology of Chromium (VI) Pollution: Microbial Diversity and Its Bioremediation Potential.” The Open Biotechnology Journal 10 (1): 379–89, https://doi.org/10.2174/1874070701610010379.Search in Google Scholar
Álvarez, S. G., M. Maldonado, A. Gerth, and P. Kuschk. 2004. “Caracterización de Agua Residual de Curtiduría y Estudio del Lirio Acuático en la Recuperación de Cromo.” Informacion Tecnologica 15 (3): 75–80, https://doi.org/10.4067/s0718-07642004000300012.Search in Google Scholar
Ambrose, K. V., Z. Tian, Y. Wang, J. Smith, G. Zylstra, B. Huang, and F. C. Belanger. 2015. “Functional Characterization of Salicylate Hydroxylase from the Fungal Endophyte Epichloë festucae.” Scientific Reports 5: 10939, https://doi.org/10.1038/srep10939.Search in Google Scholar PubMed PubMed Central
Attar, A., M. Emilia, G. Aziz, A. Christopher, and M. A. Brett. 2014. “Poly(neutral Red) Based Hydrogen Peroxide Biosensor for Chromium Determination by Inhibition Measurements.” Journal of Hazardous Materials 279: 348–55, https://doi.org/10.1016/j.jhazmat.2014.07.019.Search in Google Scholar PubMed
Avudainayagam, S., M. Megharaj, G. Owens, R. S. Kookana, D. Chittleborough, and R. Naidu. 2003. “Chemistry of Chromium in Soils with Emphasis on Tannery Waste Sites.” In Reviews of Environmental Contamination and Toxicology, 53–91. New York: Springer.10.1007/0-387-21728-2_3Search in Google Scholar PubMed
Babel, S., and T. Agustiono Kurniawan. 2004. “Cr(VI) Removal from Synthetic Wastewater Using Coconut Shell Charcoal and Commercial Activated Carbon Modified with Oxidizing Agents and/or Chitosan.” Chemosphere 54 (7): 951–67, https://doi.org/10.1016/j.chemosphere.2003.10.001.Search in Google Scholar PubMed
Bae, W. C., H. K. Lee, Y. C. Choe, D. J. Jahng, S. H. Lee, S. J. Kim, J. H. Lee, and B. C. Jeong. 2005. “Purification and Characterization of NADPH-dependent Cr(VI) Reductase from Escherichia coli ATCC 33456.” The Journal of Microbiology 43 (1): 21–7.Search in Google Scholar
Badar, U., N. Ahmed, A. J. Beswick, P. Pattanapipitpaisal, and L. E. Macaskie. 2000. “Reduction of Chromate by Microorganisms Isolated from Metal Contaminated Sites of Karachi, Pakistan.” Biotechnology Letters 22: 829–36, https://doi.org/10.1023/a:1005649113190.10.1023/A:1005649113190Search in Google Scholar
Banks, R. B., and R. T. CookeJr. 1986. “Chromate Reduction by Rabbit Liver Aldehyde Oxidase.” Biochemical and Biophysical Research Communications 137: 8–14, https://doi.org/10.1016/0006-291x(86)91168-x.Search in Google Scholar PubMed
Bishop, M. E., P. Glasser, H. Dong, B. Arey, and L. Kovarik. 2014. “Reduction and Immobilization of Hexavalent Chromium by Microbially Reduced Fe-Bearing Clay Minerals.” Geochimica et Cosmochimica Acta 133: 186–203, https://doi.org/10.1016/j.gca.2014.02.040.Search in Google Scholar
Branca, M., M. Fruianu, S. Sau, and M. A. Zoroddu. 1996. “EPR and ENDOR Studies on Monoanionic Complexes of 1, 2-semiquinones with 52Cr, 53Cr (III).” Journal of Inorganic Biochemistry 62 (3): 223–30, https://doi.org/10.1016/0162-0134(95)00156-5.Search in Google Scholar
Brigatti, M. F., C. Lugli, G. Cibin, A. Marcelli, G. Giuli, E. Paris, A. Mottana, and Z. Wu. 2000. “Reduction and Sorption of Chromium by Fe (II)-bearing Phyllosilicates: Chemical Treatments and X-Ray Absorption Spectroscopy (XAS) Studies.” Clays and Clay Minerals 48 (2): 272–81, https://doi.org/10.1346/ccmn.2000.0480214.Search in Google Scholar
Bopp, L. H., and H. L. Erlich. 1988. “Chromate Resistance and Reduction in Pseudomonas fluorescens Strain LB300.” Archives of Microbiology 150: 426–31, https://doi.org/10.1007/bf00422281.Search in Google Scholar
Campos, J., M. M. Pacheco, and C. Cervantes. 1995. “Hexavalentchromium Reduction by a Chromate-Resistant Bacillus sp. Strain.” Antonie van Leeuwenhoek 59: 229–33, https://doi.org/10.1007/bf00871816.Search in Google Scholar
Cervantes, C., and J. Campos-García. 2007. “Reduction and Efflux of Chromate by Bacteria.” In Molecular Microbiology of Heavy, edited by D. Nies and S. Silver, 407–19. Berlin: Springer.10.1007/7171_2006_087Search in Google Scholar
Chardin, B., M. T. Giudici-Orticoni, G. De Luca, B. Guigliarelli, and M. Bruschi. 2003. “Hydrogenases in Sulfate-Reducing Bacteria Function as Chromium Reductase.” Applied Microbiology and Biotechnology 63 (3): 315–21, https://doi.org/10.1007/s00253-003-1390-8.Search in Google Scholar PubMed
Chirwa, E. M. N., and Y. T. Wang. 1997. “Hexavalent Chromium Reduction by Bacillus sp. in a Packed-Bed Bioreactor.” Environmental Science and Technology 31: 1446–51, https://doi.org/10.1021/es9606900.Search in Google Scholar
Cimino, G., A. Passerini, and G. Toscano. 2000. “Removal of Toxic Cations and Cr (VI) from Aqueous Solution by Hazelnut Shell.” Water Research 34 (11): 2955–62, https://doi.org/10.1016/s0043-1354(00)00048-8.Search in Google Scholar
Civilini, M., M. de Bertoldi, and G. Tell. 1999. “Molecular Characterization of Pseudomonas aeruginosa 2NR Degrading Naphthalene.” Letters in Applied Microbiology 29: 181–6, https://doi.org/10.1046/j.1365-2672.1999.00613.x.Search in Google Scholar PubMed
Codd, R., C. T. Dillon, A. Levina, and P. A. Lay. 2001. “Studies on the Genotoxicity of Chromium: From the Test Tube to the Cell.” Coordination Chemistry Reviews 216: 537–82, https://doi.org/10.1016/s0010-8545(00)00408-2.Search in Google Scholar
Connett, P. H., and K. E. Wetterhahn. 1985. “In Vitro reaction of the Carcinogen Chromate with Cellular Thiols and Carboxylic Acids.” Journal of the American Chemical Society 107 (14): 4282–8, https://doi.org/10.1021/ja00300a035.Search in Google Scholar
Coreño-Alonso, A., F. J. Acevedo-Aguilar, G. E. Reyna-López, A. Tomasini, A. J. Fernández, K. Wrobel, K. Wrobel, and J. F. Gutiérrez-Corona. 2009. “Cr(VI) Reduction by an Aspergillus tubingensis Strain: Role of Carboxylic Acids and Implications for Natural Attenuation and Biotreatment of Cr(VI) Contamination.” Chemosphere 76: 43–7, https://doi.org/10.1016/j.chemosphere.2009.02.031.Search in Google Scholar PubMed
Coreño-Alonso, A., G. Cruz-Jiménez, L. López-Martínez, G. E. Reyna-López, and F. J. Acevedo-Aguilar. 2017. “A Rapid, Eco-Friendly, and Reliable Microplate Method for Determination of Cr(VI).” Turkish Journal of Chemistry 41 (3): 420–5, https://doi.org/10.3906/kim-1609-53.Search in Google Scholar
Dermou, E., A. Velissariou, D. Xenos, and D. V. Vayenas. 2005. “Biological Chromium (VI) Reduction Using a Trickling Filter.” Journal of Hazardous Materials B 126: 78–85, https://doi.org/10.1016/j.jhazmat.2005.06.008.Search in Google Scholar PubMed
Dmitrenko, G. N., V. V. Konovalova, and O. A. Shum. 2003. “The Reduction of Cr (VI) by Bacteria of the Genus Pseudomonas.” Microbiology 72: 370–3.10.1023/A:1024204200737Search in Google Scholar
Fedullosa, E., V. Desjardin, J. Mutar, R. Gourdon, and I. Villaescusa. 2006. “Cr(VI) Reduction into Cr(III) as a Mechanism to Explain the Low Sensitivity of Vibrio fischeri Bioassay to Detect Chromium Pollution.” Chemosphere 65: 644–50, https://doi.org/10.1016/j.chemosphere.2006.01.069.Search in Google Scholar PubMed
Francisco, R., M. C. Alpoim, and P. V. Morais. 2002. “Diversity of Chromium-resistant and-reducing Bacteria in a Chromium‐contaminated Activated Sludge.” Journal of Applied Microbiology 92 (5): 837–43, https://doi.org/10.1046/j.1365-2672.2002.01591.x.Search in Google Scholar PubMed
Fukuda, T., Y. Ishino, A. Ogawa, K. Tsutsumi, and H. Morita. 2008. “Cr (VI) Reduction from Contaminated Soils by Aspergillus sp. N2 and Penicillium sp. N3 Isolated from Chromium Deposits.” Journal of General and Applied Microbiology 54 (5): 295–303, https://doi.org/10.2323/jgam.54.295.Search in Google Scholar PubMed
Ganguli, A., and A. K. Tripathi. 1999. “Survival and Chromate Reducing Ability of Pseudomonas aeruginosa in Industrial Effluents.” Letters in Applied Microbiology 28: 76–80, https://doi.org/10.1046/j.1365-2672.1999.00457.x.Search in Google Scholar PubMed
Ganguli, A., and A. K. Tripathi. 2002. “Bioremediation of Toxic Chromium from Electroplating Effluent by Chromate-Reducing Pseudomonas aeruginosa A2Chr in Two Bioreactors.” Applied Microbiology and Biotechnology 58: 416–20, https://doi.org/10.1007/s00253-001-0871-x.Search in Google Scholar PubMed
Garbisu, C., I. Alkorta, M. J. Llama, and J. L. Serra. 1998. “Aerobic Chromate Reduction by Bacillus subtilis.” Biodegradation 9: 133–41, https://doi.org/10.1023/a:1008358816529.10.1023/A:1008358816529Search in Google Scholar PubMed
Gopalan, R., and H. Veeramani. 1994. “Studies on Microbial Chromate Reduction by Pseudomonas sp., in Aerobic Continuous Suspended Growth Culture.” Biotechnology and Bioengineering 43: 471–6, https://doi.org/10.1002/bit.260430606.Search in Google Scholar PubMed
Grund, E., B. Denecke, and R. Eichenlaub. 1992. “Naphthalene Degradation via Salicylate and Gentisate by Rhodococcus sp. strain B4.” Applied and Environmental Microbiology 58: 1874–7, https://doi.org/10.1128/aem.58.6.1874-1877.1992.Search in Google Scholar PubMed PubMed Central
Ishibashi, Y., C. Cervantes, and S. Silver. 1990. “Chromium Reduction in Pseudomonas putida.” Applied and Environmental Microbiology 56: 2268–70, https://doi.org/10.1128/aem.56.7.2268-2270.1990.Search in Google Scholar PubMed PubMed Central
Iwasaki, Y., H. Gunji, K. Kino, T. Hattori, Y. Ishii, and K. Kirimura. 2010. “Novel Metabolic Pathway for Salicylate Biodegradation via Phenol in Yeast Trichosporon Moniliiforme.” Biodegradation 21 (4): 557–64, https://doi.org/10.1007/s10532-009-9323-6.Search in Google Scholar PubMed
Jain, M., V. K. Garg, and K. Kadirvelu. 2009. “Chromium (VI) Removal from Aqueous System Using Helianthus Annuus (Sunflower) Stem Waste.” Journal of Hazardous Materials 162 (1): 365–72, https://doi.org/10.1016/j.jhazmat.2008.05.048.Search in Google Scholar PubMed
Khambhaty, Y., K. Mody, S. Basha, and B. Jha. 2009. “Kinetics, Equilibrium and Thermodynamic Studies on Biosorption of Hexavalent Chromium by Dead Fungal Biomass of Marine Aspergillus niger.” Chemical Engineering Journal 145 (3): 489–95, https://doi.org/10.1016/j.cej.2008.05.002.Search in Google Scholar
Krupka, L. R., F. A. Racle, and A. Der Marderosian. 1969. “Salicylate Degradation by Aspergillus niger: Influence of Glucose.” Journal of Pharmaceutical Sciences 58 (2): 270–2, https://doi.org/10.1002/jps.2600580236.Search in Google Scholar PubMed
Kumar, S. P., R. Suresh, K. Giribabu, R. Manigandan, S. Munusamy, S. Muthamizh, and V. Narayanan. 2015. “Synthesis and Characterization of Chromium (III) Schiff Base Complexes: Antimicrobial Activity and Its Electrocatalytic Sensing Ability of Catechol.” Spectrochimica Acta Part A: Molecular and Biomolecular Spectroscopy 139: 431–41, https://doi.org/10.1016/j.saa.2014.12.012.Search in Google Scholar PubMed
Kwak, Y. H., D. S. Lee, and H. B. Kim. 2003. “Vibrio harveyi Nitroreductase Is Also a Chromate Reductase.” Applied and Environmental Microbiology 69: 4390–5, https://doi.org/10.1128/aem.69.8.4390-4395.2003.Search in Google Scholar
Lee, K. L., H. R. Buckley, and C. C. Campbell. 1975. “An Aminoacid Liquid Synthetic Medium for the Development of Mycelial and Yeast Forms of Candida Albicans.” Journal of Medical and Veterinary Mycology 13: 148–53, https://doi.org/10.1080/00362177585190271.Search in Google Scholar PubMed
Lovely, D. R., and E. J. P. Phillips. 1994. “Reduction of Chromate by Desulfovibrio vulgaris and its c3 Cytochrome.” Applied and Environmental Microbiology 60 (2): 726–8, https://doi.org/10.1128/aem.60.2.726-728.1994.Search in Google Scholar PubMed PubMed Central
Lowry, O. H., N. J. Rosebrough, A. L. Farr, and R. J. Randall. 1951. “Protein Measurement with the Folin Phenol Reagent.” Journal of Biological Chemistry 193: 265–75, https://doi.org/10.1016/s0021-9258(19)52451-6.Search in Google Scholar
Meriah, A. Y., and T. M. Bradley. 2003. “Cr(VI) Reduction by Sulfidogenic and Nonsulfidogenic Microbial Consortia.” Applied and Environmental Microbiology 69: 1847–53, https://doi.org/10.1128/aem.69.3.1847-1853.2003.Search in Google Scholar PubMed PubMed Central
Muter, O., I. Lubinya, D. Millers, L. Grigorjeva, E. Ventinya, and A. Rapoport. 2002. “Cr (VI) Sorption by Intact and Dehydrated Candida utilis Cells in the Presence of Other Metals.” Process Biochemistry 38 (1): 123–31, https://doi.org/10.1016/s0032-9592(02)00065-1.Search in Google Scholar
Ohtake, H., E. Fuji, and K. Toda. 1990. “Bacterial Reduction of Hexavalent Chromium: Kinetic Aspects of Chromate Reduction by Enterobacter cloacae HO1.” Biocatalysis 4: 227–35, https://doi.org/10.3109/10242429008992094.Search in Google Scholar
Park, D., Y. S. Yun, J. H. Jo, and J. M. Park. 2005. “Mechanism of Hexavalent Chromium Removal by Dead Fungal Biomass of Aspergillus niger.” Water Research 39 (4): 533–40, https://doi.org/10.1016/j.watres.2004.11.002.Search in Google Scholar PubMed
Philip, L., L. Iyengar, and C. Venkobachar. 1998. “Cr (VI) Reduction by Bacillus coagulans Isolated from Contaminated Soils.” Journal of Environmental Engineering 124: 1165–70, https://doi.org/10.1061/(asce)0733-9372(1998)124:12(1165).Search in Google Scholar
Philip, L., L. Iyengar, and C. Venkobachar. 1999. “Immobilized Microbial Reactor for the Biotransformation of Hexavalent Chromium.” International Journal of Environment and Pollution 11: 202–10, https://doi.org/10.1504/ijep.1999.002258.Search in Google Scholar
Ramírez-Ramírez, R., C. Calvo-Méndez, M. Ávila-Rodríguez, P. Lappe, M. Ulloa, R. Vázquez-Juárez, and J. F. Gutiérrez-Corona. 2004. “Cr (VI) Reduction in a Chromate-Resistant Strain of Candida maltosa Isolated from the Leather Industry.” Antonie van Leeuwenhoek 85 (1): 63–8, https://doi.org/10.1023/b:anto.0000020151.22858.7f.10.1023/B:ANTO.0000020151.22858.7fSearch in Google Scholar PubMed
Romo-Rodríguez, P., F. J. Acevedo-Aguilar, A. Lopez-Torres, K. Wrobel, K. Wrobel, and J. F. Gutiérrez-Corona. 2015. “Cr (VI) Reduction by Gluconolactone and Hydrogen Peroxide, the Reaction Products of Fungal Glucose Oxidase: Cooperative Interaction with Organic Acids in the Biotransformation of Cr (VI).” Chemosphere 134: 563–70, https://doi.org/10.1016/j.chemosphere.2014.12.009.Search in Google Scholar PubMed
Santha, R., H. S. Savithri, N. A. Rao, and C. S. Vaidyanathan. 1995. “2, 3–Dihydroxybenzoic Acid Decarboxylase from Aspergillus niger: A Novel Decarboxylase.” European Journal of Biochemistry 230 (1): 104–10, https://doi.org/10.1111/j.1432-1033.1995.0104i.x.Search in Google Scholar
Sarangi, A., and C. Krishnan. 2008. “Comparison of In Vitro Cr (VI) Reduction by CFEs of Chromate Resistant Bacteria Isolated from Chromate Contaminated Soil.” Bioresource Technology 99 (10): 4130–7, https://doi.org/10.1016/j.biortech.2007.08.059.Search in Google Scholar PubMed
Sarin, V., and K. Pant. 2006. “Removal of Chromium from Industrial Waste by Using Eucalyptus Bark.” Bioresource Technology 97 (1): 15–20, https://doi.org/10.1016/j.biortech.2005.02.010.Search in Google Scholar PubMed
Selvi, K., S. Pattabhi, and K. Kadirvelu. 2001. “Removal of Cr (VI) from Aqueous Solution by Adsorption onto Activated Carbon.” Bioresource Technology 80 (1): 87–9, https://doi.org/10.1016/s0960-8524(01)00068-2.Search in Google Scholar PubMed
Shailubhai, K., R. Somayaji, N. N. Rao, and V. V. Modi. 1983. “Metabolism of Resorcinol and Salicylate in Aspergillus niger.” Experientia 39 (1): 70–2, https://doi.org/10.1007/bf01960634.Search in Google Scholar PubMed
Srivastava, S., and I. S. Thakur. 2006a. “Isolation and Process Parameter Optimization of Aspergillus sp. for Removal of Chromium from Tannery Effluent.” Bioresource Technology 97 (10): 1167–73, https://doi.org/10.1016/j.biortech.2005.05.012.Search in Google Scholar PubMed
Srivastava, S., and I. S. Thakur. 2006b. “Biosorption Potency of Aspergillus niger for Removal of Chromium (VI).” Current Microbiology 53 (3): 232–7, https://doi.org/10.1007/s00284-006-0103-9.Search in Google Scholar PubMed
Suzuki, T., N. Miyata, H. Horitsu, K. I. Kawa, K. Takamizawa, Y. Tai, and M. Okazaki. 1992. “NAD(P)H-Dependent Chromium (VI) Reductase of Pseudomonas ambigua G-1: A Cr(V) Intermediate Is Formed during the Reduction of Cr(VI) to Cr(III).” Journal of Bacteriology Aug: 5340–5, https://doi.org/10.1128/jb.174.16.5340-5345.1992.Search in Google Scholar PubMed PubMed Central
Unsal, Y. E., M. T. Üzen, and M. Soylak. 2014. “Speciation of Chromium by the Combination of Dispersive Liquid-Liquid Microextraction and Microsample Injection Flame Atomic Absorption Spectrometry.” Turkish Journal of Chemistry 38 (2): 173–81, https://doi.org/10.3906/kim-1308-56.Search in Google Scholar
Virkutyte, J., M. Sillanpää, and P. Latostenmaa. 2002. “Electrokinetic Soil Remediation—Critical Overview.” Science of the Total Environment 289 (1–3): 97–121, https://doi.org/10.1016/s0048-9697(01)01027-0.Search in Google Scholar PubMed
Wang, B., H. Yang, and W. Li. 1998. “Studies on Reduction of Hexavalent Chromium by Fungi.” Weishengwu Xuebao 38 (2): 108–13.Search in Google Scholar
Ye, J., H. Yin, B. Mai, H. Peng, H. Qin, B. He, and N. Zhang. 2010. “Biosorption of Chromium from Aqueous Solution and Electroplating Wastewater Using Mixture of Candida lipolytica and Dewatered Sewage Sludge.” Bioresource Technology 101 (11): 3893–902, https://doi.org/10.1016/j.biortech.2010.01.014.Search in Google Scholar PubMed
Zafar, S., F. Aqil, and I. Ahmad. 2007. “Metal Tolerance and Biosorption Potential of Filamentous Fungi Isolated from Metal Contaminated Agricultural Soil.” Bioresource Technology 98 (13): 2557–61, https://doi.org/10.1016/j.biortech.2006.09.051.Search in Google Scholar PubMed
Zakaria, Z. A., Z. Zakaria, S. Surif, and W. A. Ahmad. 2007. “Biological Detoxification of Cr (VI) Using Wood Husk Immobilized Acinetobacter haemolyticus.” Journal of Hazardous Materials 148: 164–71, https://doi.org/10.1016/j.jhazmat.2007.02.029.Search in Google Scholar PubMed
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