The purpose of the study was to optimize the removal of Cr(VI) by means of the Trichoderma viride strain isolated from chromium mud samples a well as the Aspergillus niger and Penicillium citrinum strains from other environments. The growth of organism and removal of chromium(VI) was carried out in water solution of various chromium(VI) contents. The research was carried out at optimal pH for each fungus i.e. Aspergillus niger 4.0, Penicillium citrinum 5.0 and Trichoderma viride 4.5. During 14 days of incubation, samples of 5 ml each were collected every day in order to determine chromium(VI) content in the solution and the efficiency of bioaccumulation of this element was then specified. Furthermore, chromium contents in filtrate and mycelium were checked to verify this type of biological activity of microorganisms. The fungi culture investigated in this study could grow at 10-125 mg/l chromium concentration which indicated that it was characterized by high tolerance to various concentrations of chromium. At 125 mg/l chromium, these organisms could accumulate successfully about 90% of chromium. High tolerance of this culture can make it a potential candidate to be a heavy metal scavenger of chromium.

Fungi are highly diverse, yet only a minor part of the total estimated species has been cultured and characterized. This might be especially true for Arctic, where studies on the fungal diversity are still scarce. For that reason, our aim was to analyze fungal diversity in the droppings of Rangifer tarandus platyrhynchus. The samples of feces from 32 adult individuals were collected in the southern or central parts of the Wedel Jarlsberg Land (Spitsbergen, Svalbard Archipelago) and assessed for micromycetes diversity using a combination of classical and molecular identification approaches. We found 16 fungal species, out of which three were described as mesophilic, two as psychrotolerant and eleven as psychrophilic. The identified Arctic fungi belonged to eleven genera out of which representatives of Naganishia genus (formerly belonging to Cryptococcus albidus clade) were the most abundant fungal species isolated. Additionally, to our knowledge, we firstly recorded Botrytis cinerea in polar areas. We conclude that droppings of R. tarandus platyrhynchus are a source of different fungal taxa, including fungi potentially pathogenic towards humans, plants and insects.