Morphological Characteristics of Aspergillus niger under Growth with Tributylphosphate

Tributyl phosphate (TBP) finds industrial application as an extractant of metal salts from ore minerals, and it is produced in large quantities. Due to the widespread use of TBP, the problem of environmental pollution with this compound and its negative impact on living organisms arises. It is shown that culture media with TBP has a strong toxic effect on Paramecium caudatum and Artemia salina. A solution to this problem could be its biodegradation enzymatic hydrolysis to inorganic phosphates. Until now, the known biodegraders of TBP were mainly bacteria. However, microscopic fungi are apparently also capable of biodegradation of this substance. The object of study is two strains of the filamentous fungi Aspergillus niger, which had previously shown the ability to use white phosphorus as a substrate. As a result of the experiments, the possibility of growth of two A. niger strains on a medium with TBP is shown. For strain F-4815D, the addition of TBP has a negative effect at the stage of conidiophore formation and spore maturation. Strain F-4815D is also characterized by a lower radial growth rate and a smaller colony diameter with the addition of TBP than strain F-4816D. Both strains are capable of growth on medium without phosphates. For strain F-4815D, the presence of TBP in the medium without inorganic phosphorus enhanced the toxic effect, which was reflected in a decrease in the diameter of colonies and hyphae, a decrease in the radial growth rate, and the later appearance of conidiophores. Strain F-4816D is more resistant to TBP, and the exclusion of inorganic phosphates from the medium stimulated the growth of the microscopic fungi, which may indicate the ability of this strain to biologically degrade TBP and reduce the toxicity.