Bioleaching Potential of Microfungi Isolated from Arctic Loparite Ore Tailings (Kola Peninsula, Northwestern Russia).

The use of rare earth elements (REE) in diverse areas of the world economy (e.g., industry, agriculture, medicine) has been significantly increased during the last decades. The mineral loparite can be considered as one of the REE sources along with bastnasite, monazite, and xenotime. The only active deposit of loparite ores in Russia is located at Kola Peninsula, northwestern Russia. The mining and processing of loparite are carried out at Lovozersky Mining and Processing Plant (MPP). In this study microfungal species isolated from the Lovozersky MPP's loparite ore concentration tailings, were studied. Based on morphological markers, a total of 15 species from nine genera have been isolated and identified. Two most dominant fungal species (Geomyces vinaceus and Penicillium simplicissimum) and two non-dominant (Aspergillus niveoglaucus and Pseudogymnoascuc pannorum), were tested in vitro on their tolerance/resistance to lanthanides (Nd and Ce). For comparison, microfungal strain Cadophora malorum, that is not isolate, was also tested. As the result, the most tolerant to both elements was P. simplicissimum which continued to grow at highest (500 mg/l) REE concentrations. Another dominant isolate G. vinaceus proved to be tolerant only to Nd and more sensitive to Ce. Our results indicate that P. simplicissimum has the potential to recover REEs such as Ce and Nd from the loparite ore concentration tails. The results obtained may be useful in order to evaluate the potential of the isolated P. simplicissimum in REE bioleaching. [ABSTRACT FROM AUTHOR]