Basidiocarps of Pleurotus ostreatus and Agrocybe cylindracea are characterized by high nutritional value and numerous medicinal activities, though bioactivities of their mycelia have not been sufficiently studied. The aim of the study was to evaluate antioxidant and antifungal potentials of P. ostreatus and A. cylindracea basidiocarp extracts, as well as those obtained from mycelia cultivated in common synthetic medium and media enriched with various agro-industrial residues. The free radical scavenging activity of the extracts was determined spectrophotometrically, based on DPPH• reduction while antifungal potential was studied by a microdilution method. The highest level of DPPH• scavenging ability was obtained by an extract of P. ostreatus mycelium cultivated in wheat bran-enriched medium, while control medium favoured the antioxidant potential of A. cylindracea mycelium. Phenol compounds were the main carriers of antioxidant activity that was demonstrated by high coefficients for correlations between total phenol contents in extracts and level of DPPH• scavenging (0.94 for P. ostreatus extracts and 0.91 for A. cylindracea extracts). Only the extracts of A. cylindracea basidiocarp and control mycelium, at a concentration of 1.33 mg/mL, inhibited the growth of Microsporum gypseum and Aspergillus flavus, while basidiocarp extract at 1.67 mg/mL also had fungicidal effect against M. gypseum. These results revealed a considerable antioxidant potential of submergedly-cultivated mycelium which showed higher antioxidant activity than basidiocarp extracts. This is very important because significant amounts of mycelium biomass could be obtained more easily, cheaper and in a more controllable way than basidiocarps cultivation.

The scientific interest in the medicinal properties of Kombucha beverages, a carbonated drink with live microorganisms, has increased recently. Hence, the aim of this study was to determine the chemical profile and to examine the antioxidant, antidiabetic and antineurodegenerative potential of unfermented and also Kombucha fermented Camellia sinensis (green tea), Coffea arabica (coffee), and Ganoderma lucidum (Reishi) extracts. The extracts were prepared as follows: the first (unfermented) set contained 1 L of water, 50 g of sucrose and 20 g of dried and ground green tea, coffee, or Reishi basidiocarp, while the second (fermented) set contained all of the aforementioned ingredients individually inoculated with Kombucha and fermented for 21 days. The chemical analysis was conducted using liquid chromatography–mass spectrometry (LC-MS). The antioxidant activity was assessed by DPPH, total reducing power (TRP), and β-carotene bleaching assays. The inhibition of α-amylase and α-glucosidase activity was used to estimate the antidiabetic potential, while the level of inhibition of acetylcholinesterase (AChE) and tyrosinase (TYR) was used to evaluate the antineurodegenerative activity. The results suggested that the fermented extracts of green tea, coffee, and Reishi exert significant antioxidant effects, although they were lower compared to the unfermented extracts. The unfermented green tea extract exhibited the highest DPPH-scavenging activity (87.46%) and the highest preservation of β-carotene (92.41%), while the fermented coffee extract showed the highest TRP (120.14 mg AAE per g) at 10 mg mL⁻¹. Although the extracts did not inhibit the activity of α-amylase, they were quite effective at inhibiting α-glucosidase, especially the unfermented Reishi extract, inhibiting 95.16% (at a concentration of 10 mg mL⁻¹) of α-glucosidase activity, which was slightly higher than the positive control at the same concentration. The most effective AChE inhibitor was unfermented green tea extract (68.51%), while the fermented coffee extract inhibited 34.66% of TYR activity at 10 mg mL⁻¹. Altogether, these results are in accordance with the differences found in the extracts’ chemical composition. Finally, this is the first report that highlights the differences in the chemical profile between the unfermented and Kombucha fermented green tea, coffee and Reishi extracts, while it also reveals, for the first time, the antineurodegenerative potential of Kombucha fermented Reishi extract. The examined extracts represent potent functional foods, while their more detailed mechanisms of action are expected to be revealed in future research.