Evaluation of the antineoplastic activity of Antarctic yeast Sporobolomyces salmonicolor grown at different culture conditions

Nowadays, deaths from neoplasms are at the top of the World Health Organization list. The interest of scientists is focused on the search for natural substrates perspective for the targeted anticancer chemotherapy. Antarctic yeasts represent an unexplored object regarding their antineoplastic potential. The studies in the present work demonstrated the capacity of Sporobolomyces salmonicolor AL₃₆ for cell growth in different cultivation processes. During the transfer of small-scale flasks cultivation to the bioreactor system, optimal biomass quantities of approximately 6.0 g/L were recorded. A comparative examination of the metabolic profiles of the two extracts tested reveals differences in the synthesized molecules corresponding to different cytotoxicity (antineoplastic activity) in vitro on malignant cell lines. The median inhibitory concentration (IC₅₀) of each extract determined by the MTT test was used as a parameter for evaluating the antiproliferative effects. Most sensitive to the in vitro effect of the extract of Sp. salmonicolor AL₃₆ cultivated in flasks was the cell line SKW-3 (T cell leukemia, derivative of KE-37) - IC₅₀ = 35.3 µg/ml, while the bioreactor biomass extract was most cytotoxic for RPMI-8226 (multiple myeloma) cells - IC₅₀ = 28.27µg/ml. The proteome analysis of treated and untreated malignant cells showed that both yeast extracts have a strong potential to inhibit anti-apoptotic proteins which reveals a mode of action related to induction of apoptosis and proliferation inhibition.