Martin Pavlík

Natural Ophiocordyceps sinensis is a highly valued medicinal fungus known for its antitumor, immunomodulatory, and antiviral properties. Due to extensive overharvesting in Asia, cultivated alternatives have become increasingly important. This study aimed to evaluate the biological activity and chemical composition of extracts obtained from cultivated Ophiocordyceps sinensis grown using different rice substrates. Methanolic extracts were prepared from solid-state cultivated Ophiocordyceps sinensis grown on Oryza sativa var. indica and Oryza sativa var. japonica. Antioxidant activity was determined using the DPPH assay, while proteolytic activity was evaluated with the azocasein substrate. Chemical characterization of major compounds was performed using ¹D and ²D NMR spectroscopy, together with IR spectroscopy. UV/Vis spectrophotometry was employed to confirm the formation of silver nanoparticles in AgNO₃ solution. Antimicrobial activity was tested against bacterial strains, including Escherichia coli and Staphylococcus aureus. All prepared methanolic extracts exhibited measurable antioxidant and proteolytic activities. The dominant identified compounds were Z-oleic acid, linoleic acid, and D-mannitol. Selected extracts successfully induced the formation of silver nanoparticles. The highest antimicrobial activity against Escherichia coli was observed for sample 1OS, reaching a mean % RIZD value of 129.32 ± 0.58%.

Ambrosia beetles, particularly invasive species within the tribe Xyleborini, such as Xylosandrus germanus (Blandford, 1894), pose significant threats to various ecosystems and managed habitats worldwide. Monitoring these invaders is vital for effective pest management, typically accomplished through ethanol-baited traps. We compared trap efficacy using denatured ethanol versus absolute ethanol in orchards, tree nurseries, and lumber yards in northeastern Ohio, USA, finding that absolute ethanol traps captured significantly more X. germanus. Analysis revealed acetone, ethanol, and methyl isobutyl ketone in the denatured ethanol, likely impacting trap efficacy. Our study underscores the importance of using pure denatured ethanol without acetone for effective monitoring, especially for X. germanus. Exotic xyleborines dominated trap captures across various habitats, emphasizing the need for tailored pest management strategies. Further research is warranted to explore the chemical ecology of ambrosia beetles and the influence of ethanol impurities on trap effectiveness.

Bareroot European beech (Fagus sylvatica L.) seedlings are frequently used in reforestation programs in Central Europe. However, beech outplanting is often unsuccessful due to drought stress. In this study, the effects of a simulated water deficit and of a hydrogel and ectomycorrhizal fungi (EMF) application were estimated on the development of 1 + 1 beech seedlings. The roots of 1-year-old bareroot seedlings were treated with the additives at the time of transplanting to pots in spring and then exposed to the whole growing season under different watering regimes: (i) full watering (FW; volumetric water content 70%), (ii) reduced watering (RW; 40%), (iii) periodic watering (PW; substrate rewetted to 70% after drying), and (iv) no watering (NW). Almost all FW seedlings survived the whole growing season, whereas all NW seedlings died after 17 weeks of desiccation. The survival and growth of FW and NW seedlings were significantly higher and lower, respectively, than those under both PW and RW treatments. The additives significantly increased survival in RW seedlings only but had no effect on growth. A promoting effect of FW on the chlorophyll a fluorescence parameters was found. The number and EMF colonization of the short roots were significantly lower in FW seedlings compared to the other watering treatments. The additives did not affect these parameters. The occurrence of neither treatment-specific EMF root morphotype nor fungi applied in the inoculum and traced by molecular analysis indicated the formation of ectomycorrhizas with native EMF in all treatments. The seedlings in the water-deficient treatments exhibited higher foliar nutrient concentrations than FW seedlings. The additives increased the concentration of nutrients in PW and phosphorus in NW seedlings. The results suggest the significant effect of the water supply, but a weaker effect of the additives tested on beech seedling development under experimental conditions.

Production of carbon dioxide, as one of the ultimate products of fungal metabolism, can be used to quantify and measure their metabolic rate under different conditions, thus aiding in finding the optimal substrate and environment for cultivation of wood-destroying fungi. This study is focused on species Pleurotus ostreatus and Ganoderma lucidum,. These species are also cultivated for mycorestoration as well as their medicinal and nutritional value. To quantify their metabolical rate on various substrates (agar medium, wood chips, rye straw), multiple custom-built airtight chambers were equipped with CO₂ probes (GMP 343, Vaisala, Finland) to measure the production of carbon dioxide. The highest values were measured during the primordial production on rye straw substrate, with the average values of 1.09 g CO₂ kg⁻¹ (substrate) h⁻¹. These values varied significantly between various substrates, fungal species and development stages.

This paper addresses the processes and investment evaluation of utilizing available dendromass in an easy and close-to-nature way under Central European conditions in Slovakia. Wood of the European aspen (Populus tremula L.) that has generally been considered of little economic value was efficiently used as a growth medium for the oyster mushroom (Pleurotus ostreatus (Jacq.) P. Kumm.). The production of the fruiting bodies of this mushroom were evaluated for 5 years under natural forest conditions. The evaluation focused solely on aspen wood, specifically, the most valuable part – the trunk. The investment assessment revealed the high economic value of the fruiting bodies of the oyster mushroom inoculated into aspen wood blocks for the period of five years. In particular, the results of the net present value (NPV = 347.78 €/m³) as well as the profitability index (PI = 1.63) and discounted payback period (DPP ≈ 2 years and 8 months) point to the high profitability of such a project under the given conditions. The results could be helpful and inspiring for forest and garden owners when deciding how to utilize low-value waste dendromass, low-quality aspen wood and other tree species in small-scale forest management.

The paper presents the ecological distribution of edible and medicinal mushroom Polyporus umbellatus in Central Europe, the main motivation is to inform on the potential of commercial cultivation of this species. All data considered in this study are based on records from 70 localities in Slovakia. Fruiting bodies and sclerotia have been recorded in forests with dominance of beech, hornbeam and oak, at altitudes ranging from 150 to 935 m, with average altitude of 403 m. In Slovakia, these areas correspond to warm hilly and upland beech-oak and oak-beech forests. Mean air annual temperature between 6°C and 9°C characterizes about 94% of the areas. Continuous monitoring of fruiting body production at 13 plots has shown peak growth in August. In total, 192 fruiting bodies were recorded over the period of five years. This species predominantly occurs on acidic soils (pH interval 4.5–4.99), with no individuals found in soils with pH value above 7.0. Our findings can be used for growing the fungus and its expansion to new regions not only in Central Europe.

V s??asnej dobe existuje 750 druhov h?b rodu Cordyceps. Vysok? cena pr?rodn?ho Cordycepsu a jej nedostatok v pr?rode sp?sobil, ?e sa pozornos? upriamila na jej pestovanie, kultiv?ciu v laborat?rnych podmienkach. Dopyt po tejto "hube-paraz... V s??asnej dobe existuje 750 druhov h?b rodu Cordyceps. Vysok? cena pr?rodn?ho Cordycepsu a jej nedostatok v pr?rode sp?sobil, ?e sa pozornos? upriamila na jej pestovanie, kultiv?ciu v laborat?rnych podmienkach. Dopyt po tejto "hube-paraz...

The research work deals with the study of the influence of the substrate on the antioxidant activity of the alcoholic extracts of Paecilomyces hepiali. In this case, substrates as corn, rice, millet and peas were used. The antioxidant activity was measured by the use of 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical scavenging method. All measurements were carried out in the concentration range of extracts: 6.25, 3.12, 1.56, 0.78, 0.39 mg/mL. Overall antioxidant activity was expressed as IC50DPPH for the seven methanolic and for the seven ethanolic extracts. Based on a comparison of the values of the IC50 DPPH we can conclude that the methanolic extracts are more active in scavenging of a stable DPPH radical compared with the ethanolic extracts. The most suitable substrate for the cultivation of Paecilomyces hepiali with content of the substances with antioxidant properties was a rice with the addition of non-defatted soy flour. The most effective extract in the scavenging of a stable radical was a methanol extract No.4 (IC50DPPH = 2.33 mg/mL) cultivated on the rice with the addition of non-defatted soy flour. The methanol extract of sample No.7 cultivated on peas (IC50DPPH) = 11.50 mg/mL was a less effective. By the crystallization of these extracts, we managed to obtain sufficient quantities of the six samples in solid state, from which the IR spectra were measured; which confirmed the presence of the amino acids in extracts.

Current research is focused on testing the cultivation of Paecilomyces hepiali mycelia on various plant substrates and producing fungus or mycelial biomass with qualitatively interesting substances. P. hepiali mycelia was cultivated using solid-state fermentation of different substrates. Mycelial biomass was then analyzed, and antioxidant activity was evaluated using the DPPH radical scavenging method for different ethanolic extracts based on a millet substrate (extract 1) or a chickpea substrate (extract 2). Extract 1 corresponds to a half-maximal DPPH radical inhibitory concentration of 1.73 mg/mL; the inhibitory concentration of ethanol extract 2 was almost 4.5 times higher at 7.92 mg/mL. Extracts 1 and 2 were separated into fractions by column chromatography and the chemical structures were determined for the substances that formed the most effective fraction of sample 1. The chemical structures of all compounds in the most active fraction of sample 1 were analyzed by 1H, 13C, distortionless enhancement by polarization transfer, correlation spectroscopy, heteronuclear single-quantum correlation spectroscopy, and heteronuclear multiple-bond correlation spectra.