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Hexavalent Chromium Removal by a Paecilomyces sp. Fungal Strain Isolated from Environment.

Cárdenas-González JF, Acosta-Rodríguez I - Bioinorg Chem Appl (2010)

Bottom Line: A resistant and capable fungal strain in removing hexavalent chromium was isolated from an environment near of Chemical Science Faculty, located in the city of San Luis Potosí, Mexico.Strain resistance of the strain to high Cr (VI) concentrations and its ability to reduce chromium were studied.When it was incubated in minimal medium with glucose, another inexpensive commercial carbon source like unrefined and brown sugar or glycerol, in the presence of 50 mg/L of Cr (VI), the strain caused complete disappearance of Cr (VI), with the concomitant production of Cr (III) in the growth medium after 7 days of incubation, at 28 degrees C, pH 4.0, 100 rpm, and an inoculum of 38 mg of dry weight.

View Article: PubMed Central - PubMed

Affiliation: Laboratorio de Micología Experimental, Centro de Investigación y de Estudios de Posgrado, Facultad de Ciencias Químicas, Universidad Autónoma de San Luis Potosí, Avenue Dr. Manuel Nava No. 6, Zona Universitaria, 78320 San Luis Potosí, SLP, Mexico.

ABSTRACT
A resistant and capable fungal strain in removing hexavalent chromium was isolated from an environment near of Chemical Science Faculty, located in the city of San Luis Potosí, Mexico. The strain was identified as Paecilomyces sp., by macro- and microscopic characteristics. Strain resistance of the strain to high Cr (VI) concentrations and its ability to reduce chromium were studied. When it was incubated in minimal medium with glucose, another inexpensive commercial carbon source like unrefined and brown sugar or glycerol, in the presence of 50 mg/L of Cr (VI), the strain caused complete disappearance of Cr (VI), with the concomitant production of Cr (III) in the growth medium after 7 days of incubation, at 28 degrees C, pH 4.0, 100 rpm, and an inoculum of 38 mg of dry weight. Decrease of Cr (VI) levels from industrial wastes was also induced by Paecilomyces biomass. These results indicate that reducing capacity of chromate resistant filamentous fungus Cr (VI) could be useful for the removal of Cr (VI) pollution.

No MeSH data available.


Related in: MedlinePlus

Time-course of Cr (VI) decrease and Cr (III) production in the spent medium of culture initiated in Lee's minimal medium, amended with 50 mg/L Cr (VI). 100 rpm, 28°C, pH 4.0.
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fig6: Time-course of Cr (VI) decrease and Cr (III) production in the spent medium of culture initiated in Lee's minimal medium, amended with 50 mg/L Cr (VI). 100 rpm, 28°C, pH 4.0.

Mentions: The ability of the isolated strain to lower the initial Cr (VI) of 50 mg/L and Cr (III) production in culture medium was analyzed. Figure 6 shows that Paecilomyces sp. exhibited a remarkable efficiency to diminish Cr (VI) level with the concomitant production of Cr (III) in the growth medium. Thus, after 7 days of incubation, the fungus strain caused a drop in Cr (VI) from its initial concentration of 50 mg/L to almost undetectable levels, and the decreased level occurred without significant change in total Cr content. As expected, total Cr concentration remained constant over time, in medium without inoculum. These observations indicate that Paecilomyces sp. strain is able to reduce Cr (VI) to Cr (III) in growth medium amended with chromate. There are two mechanisms by which chromate could be reduced to a lower toxic oxidation state by an enzymatic reaction. Currently, we do not know whether the fungal strain used in this study expresses Cr (VI) reducing enzyme(s). Further studies are necessary to extend our understanding of the effects of coexisting ions on the Cr (VI) reducing activity of the strain reported in this study. Cr (VI) reducing capability has been described in some reports in the literature [2, 8, 11–14, 19, 20, 22, 24, 27]. Biosorption is the second mechanism by which the chromate concentration could be reduced, and 1 g of fungal biomass of Paecilomyces sp. is able to remove 1000 mg/L of Cr (VI) at 60°C, at 3 hours of incubation (date not shown), because the fungal cell wall can be regarded as a mosaic of different groups that could form coordination complexes with metals, and our observations are like most of the reports in the literature [1, 3, 5, 7–9, 18, 21–24].


Hexavalent Chromium Removal by a Paecilomyces sp. Fungal Strain Isolated from Environment.

Cárdenas-González JF, Acosta-Rodríguez I - Bioinorg Chem Appl (2010)

Time-course of Cr (VI) decrease and Cr (III) production in the spent medium of culture initiated in Lee's minimal medium, amended with 50 mg/L Cr (VI). 100 rpm, 28°C, pH 4.0.
© Copyright Policy - open-access
Related In: Results  -  Collection

Show All Figures
getmorefigures.php?uid=PMC2902107&req=5

fig6: Time-course of Cr (VI) decrease and Cr (III) production in the spent medium of culture initiated in Lee's minimal medium, amended with 50 mg/L Cr (VI). 100 rpm, 28°C, pH 4.0.
Mentions: The ability of the isolated strain to lower the initial Cr (VI) of 50 mg/L and Cr (III) production in culture medium was analyzed. Figure 6 shows that Paecilomyces sp. exhibited a remarkable efficiency to diminish Cr (VI) level with the concomitant production of Cr (III) in the growth medium. Thus, after 7 days of incubation, the fungus strain caused a drop in Cr (VI) from its initial concentration of 50 mg/L to almost undetectable levels, and the decreased level occurred without significant change in total Cr content. As expected, total Cr concentration remained constant over time, in medium without inoculum. These observations indicate that Paecilomyces sp. strain is able to reduce Cr (VI) to Cr (III) in growth medium amended with chromate. There are two mechanisms by which chromate could be reduced to a lower toxic oxidation state by an enzymatic reaction. Currently, we do not know whether the fungal strain used in this study expresses Cr (VI) reducing enzyme(s). Further studies are necessary to extend our understanding of the effects of coexisting ions on the Cr (VI) reducing activity of the strain reported in this study. Cr (VI) reducing capability has been described in some reports in the literature [2, 8, 11–14, 19, 20, 22, 24, 27]. Biosorption is the second mechanism by which the chromate concentration could be reduced, and 1 g of fungal biomass of Paecilomyces sp. is able to remove 1000 mg/L of Cr (VI) at 60°C, at 3 hours of incubation (date not shown), because the fungal cell wall can be regarded as a mosaic of different groups that could form coordination complexes with metals, and our observations are like most of the reports in the literature [1, 3, 5, 7–9, 18, 21–24].

Bottom Line: A resistant and capable fungal strain in removing hexavalent chromium was isolated from an environment near of Chemical Science Faculty, located in the city of San Luis Potosí, Mexico.Strain resistance of the strain to high Cr (VI) concentrations and its ability to reduce chromium were studied.When it was incubated in minimal medium with glucose, another inexpensive commercial carbon source like unrefined and brown sugar or glycerol, in the presence of 50 mg/L of Cr (VI), the strain caused complete disappearance of Cr (VI), with the concomitant production of Cr (III) in the growth medium after 7 days of incubation, at 28 degrees C, pH 4.0, 100 rpm, and an inoculum of 38 mg of dry weight.

View Article: PubMed Central - PubMed

Affiliation: Laboratorio de Micología Experimental, Centro de Investigación y de Estudios de Posgrado, Facultad de Ciencias Químicas, Universidad Autónoma de San Luis Potosí, Avenue Dr. Manuel Nava No. 6, Zona Universitaria, 78320 San Luis Potosí, SLP, Mexico.

ABSTRACT
A resistant and capable fungal strain in removing hexavalent chromium was isolated from an environment near of Chemical Science Faculty, located in the city of San Luis Potosí, Mexico. The strain was identified as Paecilomyces sp., by macro- and microscopic characteristics. Strain resistance of the strain to high Cr (VI) concentrations and its ability to reduce chromium were studied. When it was incubated in minimal medium with glucose, another inexpensive commercial carbon source like unrefined and brown sugar or glycerol, in the presence of 50 mg/L of Cr (VI), the strain caused complete disappearance of Cr (VI), with the concomitant production of Cr (III) in the growth medium after 7 days of incubation, at 28 degrees C, pH 4.0, 100 rpm, and an inoculum of 38 mg of dry weight. Decrease of Cr (VI) levels from industrial wastes was also induced by Paecilomyces biomass. These results indicate that reducing capacity of chromate resistant filamentous fungus Cr (VI) could be useful for the removal of Cr (VI) pollution.

No MeSH data available.


Related in: MedlinePlus