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A new exopolysaccharide preparation isolated from stationary cultures of the white rot fungus Ganoderma applanatum (GpEPS) was tested in terms of its bioactive properties including its cytotoxic and immunostimulatory effect. The results indicate that the tested GpEPS (at concentrations above 22.85 µg/mL and 228.5 µg/mL) may exhibit selective activity against tumor cells (cell lines SiHa) and stimulate production of TNF-α THP-1-derived macrophages at the level of 752.17 pg/mL. The GpEPS showed antibacterial properties against Staphyloccoccus aureus and a toxic effect against Vibrio fischeri cells (82.8% cell damage). High cholesterol-binding capacity and triglycerides-binding capacity (57.9% and 41.6% after 24 h of incubation with the tested substances, resp.) were also detected for the investigated samples of GpEPS.

Three bioactive fractions, extracellular laccase (ex-LAC), crude endopolysaccharides (c-EPL), and a low molecular subfraction of secondary metabolites (ex-LMS), were isolated from the idiophasic cultures of the white rot fungus Cerrena unicolor. For the first time, we determined the antioxidant properties of these samples by chemiluminometric measurement (a) and assessment of the scavenging effect on ABTS (b) and the DPPH reduction rate (c). The highest reducing capability was found for the ex-LMS fraction: 39-90% for (a), 20-90% for (b), and 10-59% for (c) at the concentration of 6.25-800 µg/mL. The scavenging abilities of the C. unicolor c-EPL were between 36 and 70% for (a), 2 and 60% for (b), and 28 and 32% for (c) at the concentration of 6.25-800 µg/mL. A very high prooxidative potential was observed for the ex-LAC probes. The preliminary toxicity tests were done using the Microtox system and revealed the following percentage of the toxic effect against Vibrio fischeri: 85.37% for c-EPL, 50.67% for ex-LAC, and 99.8% for ex-LMS, respectively. The ex-LAC sample showed the antibacterial activity against Escherichia coli, c-EPL against Staphylococcus aureus, and ex-LMS against both bacterial strains, respectively, but the stronger inhibitory effect was exerted on S. aureus.