Isolation of a strain of Aspergillus fumigatus able to grow in minimal medium added with an industrial cyanide waste

Abstract

The present note refers the results about the isolation of an Aspergillus fumigatus strain able to grow on an industrial cyanide waste as nitrogen source. The fungus was selected from an alkaline unpolluted soil in enrichment cultures in 50 ml of Minimal Medium added with 20 mmol glucose and supplemented initially with 0.1 mmol KCN and then with 70 μl of a waste solution from a jewelry industry containing free cyanide and cyanide complexes of heavy metal ions including copper, silver, nickel, and others. The cyanide content of the waste was 1,500 ppm. The fungal growth was monitored determining dry weight, protein content and glucose consumption. The fungus efficiently utilized the cyanide as evidenced by the decrease in the inoculated medium of the compound under detection limits within 24 h and the concomitant growth within 15 days during which periodical additions of the waste to the cultures were made. The amount of the cyanide in the biomass of the fungus grown in presence of the waste was very scarce and comparable to that in absence of the pollutant. Furthermore the fungus was able to sequestrate metals such Ag, Cu, and Ni as a resistance mechanism against heavy metals. In conclusion our results are of interest for biodegradation plans of electroplating industrial wastes containing cyanide based pollutants.

The High-Throughput Screening of Microorganisms to Eliminate Ethyl Carbamate in Chinese Liquor

“…LB medium: 10.0 g/L peptone, 5.0 g/L yeast extract, 10.0 g/L NaCl. Minimal medium: 20.0 g/L glucose, 1.0 g/L yeast extract, 6.8 g/L Na 2 HPO 4 ·7H 2 O, 3.0 g/L KH 2 PO 4 , 0.5 g/L NaCl, 0.01 g/L CaCl 2 , 1 mL of trace metal solution (H 3 BO 3 30 mg/L; CoCl 2 ·6H 2 O 200 mg/L; ZnSO 4 ·7H 2 O 100 mg/L; MnCl 2 ·4H 2 O 10 mg/L; pH 6.0) and increasing content of cyanide (25 mg/L, 100 mg/L, 200 mg/L), pH 8.0 [ 24 ]. Glucose inorganic salt medium (GI): 50.0 g/L glucose, 10.0 g/L peptone, 5.0 g/L (NH 4 ) 2 SO 4 , 2.0 g/L KH 2 PO 4 , 1.0 g/L MnCl 2 , 5.0 g/L NaCl, pH 7.0–7.2.…”

Biological degradation of cyanide using native bacteria isolated from a cassava-processing effluent.

“…This occurs most often from nitriles or free cyanide; however, metal-complexed cyanide has also been reported to be attenuated biologically, but in most studies, it is difficult to determine whether the attenuation was by direct utilization of the complex or by utilization of free cyanide released by complex dissociation (JOHNSON, 2015). (SABATINI et al, 2012). These studies have shown that microbes adapt to hostile environments and therefore, cyanide-degrading species can be isolated from cyanide-containing wastes and they could be adapted to toxic concentrations as high as the one present in the waste from which they were adapted.…”