Wheat Straw Degradation by Trametes gibbosa: The Effect of Calcium Ions

Wheat straw is the major crop residue in Europe which makes it the most promising material for bioconversion. However, only 3% of annual production is used directly while the rest is considered as waste. A key step in processing of lignocellulosics is delignification by fungi and the presence of calcium can be of a great importance as it can modulate ligninolytic enzymes activities. Trametes gibbosa BEOFB 310 was used for solid-state fermentation of wheat straw in the presence of calcium in different concentrations. Samples were extracted after 19days of fermentation and activities of Mn-oxidizing peroxidases and laccase were determined spectrophotometrically. Quantitative procedures were used to determine contents of hemicelluloses, cellulose, and lignin. Calcium induced activity of Mn-dependent peroxidase to a concentration of 5.0mM (7185.2 +/- 791.4 UL-1), which was threefold higher than in the control. Lignocellulose loss in wheat straw was stimulated by calcium addition and the maximum delignification was detected at concentration of 5.0mM (52.9 +/- 0.9%). Delignification was positively correlated to activity of Mn-dependent peroxidase. This study showed that wheat straw supplementation with calcium can significantly improve solid-state fermentation by increasing Trametes gibbosa Mn-dependent peroxidase activity and augmenting lignin degradation

Stimulation of Wood Degradation by Daedaleopsis confragosa and D. tricolor

Biological pretreatment of the lignocellulosic residues, in which white-rot fungi have a crucial role, has many advantages compared to the chemical, physical, and physico-chemical methods of delignification and therefore attracts increasing scientific attention. Regarding the fact that properties and capacities of the ligninolytic enzymes of Daedaleopsis spp. are still unknown, the aim of this study was to research how nitrogen sources and inducers affect the potential of Daedaleopsis confragosa and Daedaleopsis tricolor to degrade cherry sawdust. NH4NO3, (NH4)2SO4, and peptone were tested as nitrogen sources, while veratryl alcohol, p-anisidine, vanillic acid, and phenylmethylsulfonyl fluoride were the studied inducers. As Mn-dependent peroxidase and laccase were the leader enzymes and cherry sawdust/peptone medium the best stimulator of their activities, the effect of inducers on delignification potential of these species was studied during fermentation of that substrate. Veratryl alcohol was the best stimulator of laccase and phenylmethylsulfonyl fluoride of Mn-dependent peroxidase activity (27,610.0 and 1338.4 U/L, respectively). These inducers also increased cherry sawdust delignification selectivity, particularly in D. tricolor in the presence of phenylmethylsulfonyl fluoride (lignin:hemicellulose:cellulose = 32.1%:0.9%:11.7%). Owing to the presented results, studied species could have an important role in the phase of lignocellulose pretreatment in various biotechnological processes. © 2018, Springer Science+Business Media, LLC, part of Springer Nature

Induction of wheat straw delignification by Trametes species

Wheat straw is the major crop residue in European countries which makes it the most promising material for bioconversion into biofuels. However, cellulose and hemicellulose are protected with lignin, so delignification is an inevitable phase in lignocellulose processing. The organisms predominantly responsible for its degradation are white-rot fungi and among them Trametes species represent promising degraders due to a well-developed ligninolytic enzyme system. Although numerous studies have confirmed that low molecular weight compounds can induce the production and activity of ligninolytic enzymes it is not clear how this reflects on the extent of delignification. The aim of the study was to assess the capacity of p-anisidine and veratryl alcohol to induce the production and activity of Mn-oxidizing peroxidases and laccases, and wheat straw delignification by six Trametes species. Significant inter- and intraspecific variations in activity and features of these enzymes were found, as well as differences in the potential of lignocellulose degradation in the presence or absence of inducers. Differences in the catalytic properties of synthesized enzyme isoforms strongly affected lignin degradation. Apart from enhanced lignin degradation, the addition of p-anisidine could significantly improve the selectivity of wheat straw ligninolysis, which was especially evident for T. hirsuta strains

Recent progress in research on the pharmacological potential of mushrooms and prospects for their clinical application

International audienceFungi are considered one of the most diverse, ecologically significant, and economically important organisms on Earth. The edible and medicinal mushrooms have long been known by humans and were used by ancient civilizations not only as valuable food but also as medicines. Mushrooms are producers of high- and low-molecular-weight bioactive compounds (alkaloids, lectins, lipids, peptidoglycans, phenolics, polyketides, polysaccharides, proteins, polysaccharide-protein/peptides, ribosomal and non-ribosomal peptides, steroids, terpenoids, etc.) possessing more than 130 different therapeutic effects (analgesic, antibacterial, antifungal, anti-inflammatory, antioxidant, antiplatelet, antiviral, cytotoxic, hepatoprotective, hypocholesterolemic, hypoglycemic, hypotensive, immunomodulatory, immunosuppressive, mitogenic/regenerative, etc.). The early record of Materia Medica shows evidence of using mushrooms for treatment of different diseases. Mushrooms were widely used in the traditional medicine of many countries around the world and became great resources for modern clinical and pharmacological research. However, the medicinal and biotechnological potential of mushrooms has not been fully investigated. This review discusses recent advances in research on the pharmacological potential of mushrooms and perspectives for their clinical application