A Variety of Fungal Species on the Green Frogs' Skin (Pelophylax esculentus complex) in South Banat.

In the last several decades, amphibian populations have been declining worldwide. Many factors have been linked to global amphibian decline, including habitat destruction, pollution, introduced species, global environmental changes, and emerging infectious diseases. Recent studies of amphibian skin infections were mainly focused on the presence of chytridiomycosis, neglecting other members of the frogs' skin communities. The diversity pattern of fungal dwellers on the skin of green frogs (Pelophylax esculentus complex) was investigated. A total of 100 adults were sampled from three localities in South Banat (northern Serbia) over three consecutive years and detected fungal dwellers were identified using light microscopy and ITS and BenA gene sequencing. Structures belonging to fungi and fungus-like organisms including a variety of spores and different mycelia types were documented in the biofilm formed on amphibian skin, and are classified into 10 groups. In total, 42 fungal isolates were identified to species, section, or genus level. The difference in mycobiota composition between sampling points (localities and green frog taxa) was documented. The highest number of fungal structures and isolates was recorded on the hybrid taxon P. esculentus and locality Stevanove ravnice. Parental species showed a markedly lower diversity than the hybrid taxon and were more similar in diversity patterns and were placed in the same homogenous group. The locality Stevanove ravnice exhibited more pronounced differences in diversity pattern than the other two localities and was placed in a distinct and separate homogenous group. Among the fungal isolates, the highest isolation frequency was documented for Alternaria alternata, Aspergillus sp. sect. Nigri, Epicoccum nigrum, Fusarium proliferatum, and Trichoderma atroviride. Among the documented species, dematiaceous fungi, causative agents of chromomycosis in amphibians, were also recorded in this research with high isolation frequency. Also, some rare fungal species such as Quambalaria cyanescens and Pseudoteniolina globosa are documented for the first time in this research as microbial inhabitants of amphibian skin.

Penicillium and Talaromyces Species as Postharvest Pathogens of Pear Fruit (Pyrus communis) in Serbia.

Pears are one of the oldest and the third most important fruit species grown in temperate regions. They are consumed because of their nutritional and health benefits, in fresh form or as various processed products. This article resolves the etiology of the Penicillium-like mold symptoms on pear fruits in Serbia. Samples of pear fruits with blue mold and other Penicillium-like mold symptoms were collected in Serbia from 2016 to 2019, from four storages. The recovered isolates were identified and characterized according to a polyphasic approach. Morphological and physiological analyses were performed on three media and five temperatures, respectively. Four loci (internal transcribed spacer, beta-tubulin, calmodulin, and DNA-dependent RNA polymerase II second largest subunit) were used for sequencing, genetic identification, and phylogenetic analyses. The results of the identification by conventional and molecular methods were in agreement, and they revealed that the obtained isolates belong to five species: Penicillium crustosum, P. expansum, P. italicum, Talaromyces minioluteus, and T. rugulosus. In a pathogenicity test, P. crustosum, P. expansum, T. minioluteus, and T. rugulosus produced decay on artificially inoculated pear fruits, and P. italicum induced tissue response lesions. The results of this study are the first reports of T. minioluteus and T. rugulosus as postharvest pear pathogens. Also, these are the first world records of T. minioluteus, T. rugulosus, and P. italicum on fruits of European pear. Furthermore, this is the first finding of P. crustosum, P. expansum, P. italicum, T. minioluteus, and T. rugulosus on pear fruit in Serbia.

Bat guano-dwelling microbes and antimicrobial properties of the pygidial gland secretion of a troglophilic ground beetle against them.

Bat guano is an important source of microbial diversity in caves and can be a source of potential pathogens. Laemostenus (Pristonychus) punctatus is a guanophilic ground beetle species, which pygidial gland secretion exhibits action against pathogenic and other microbes. The distribution and diversity of microbes in bat guano from a karstic cave were determined in this study. Additionally, antimicrobial activity of the pygidial gland secretion of L. (P.) punctatus against guano-dwelling microbes was tested; minimal inhibitory concentration (MIC) and chemical composition of the secretion were analyzed. In total, 63 different bacterial species and 16 fungal morphotypes were isolated from guano samples by the cultivation method and confirmed using and phenotypic characterization and molecular identification. There was a difference in the composition of certain microorganisms between the sampling points (cave locations) and between the guano layers. The largest number of bacterial isolates belongs to the genera Lysinibacillus and Paenibacillus, while Pseudomonas species were highly abundant at the innermost sampling point. For the guanophilic fungi, the majority are ascomycetes, with Penicillium and Aspergillus as the most dominant genera. Meyerozyma guilliermondii was the only yeast species found in the guano samples. The most sensitive isolates were Enterococcus eurekensis (MIC 0.007 mg/mL) and Escherichia fergusonii (MIC 0.028 mg/mL). The most sensitive fungal isolates were M. guilliermondii, Penicillium expansum, and Trichoderma harzianum (MIC 0.15 mg/mL). This study opens a new possibility for better understanding of ecological relations between microorganisms and troglophilic ground beetles and for detailed investigations of morpho-anatomical aspects of pygidial glands.

Characterization of Alternaria Species Associated with Leaf Spot Disease of Armoracia rusticana in Serbia.

Leaf spot diseases caused by Alternaria species have been reported worldwide in plants in the Brassicaceae family. However, there is little information on Alternaria species causing diseases in horseradish. In the present study, 89 Alternaria spp. isolates from Armoracia rusticana, sampled from nine districts in Serbia, were characterized based on their morphology, physiology, and molecular markers. Morphological characterization and molecular analyses based on ITS, GAPDH, Alt a 1, and PM-ATP sequences identified three distinct species associated with the disease: Alternaria brassicae, A. brassicicola, and A. alternata. For all species, growth and sporulation rates at 0, 5, 10, 15, 20, 25, 30, 35, and 40°C showed a quadratic response, with A. alternata having the widest temperature optimum (20 to 30°C) while A. brassicicola had higher optimum temperatures (20 to 25°C) than A. brassicae (15 to 20°C). To gain a better understanding of the pathogenicity of these species, the influence of leaf age, host susceptibility, and ability to infect artificially wounded and nonwounded leaves were tested. The pathogenicity test identified A. brassicicola and A. brassicae as the main causal agents of horseradish leaf spot disease. Results indicated that young and intact leaves of horseradish and cabbage were less susceptible to infection and also suggested the potential for cross-infection between these two hosts. Haplotype networks showed haplotype uniformity for A. brassicae, two haplotype groups of A. brassicicola, and eight haplotype groups of A. alternata in Serbia and suggest the possible association of some haplotypes with the geographic area. This study is the first to investigate Alternaria leaf spot disease on A. rusticana in Serbia and is the first record of A. brassicicola on horseradish in this country.

Talaromyces minioluteus: New Postharvest Fungal Pathogen in Serbia.

Talaromyces minioluteus is one of the important species of genus Talaromyces, which has cosmopolitan distribution and is encountered on a wide range of different habitats. This species has not been considered as an important plant pathogen, even though it has been isolated from various plant hosts. Fruits and vegetables with Penicillium-like mold symptoms were collected from 2015 to 2017 from markets in Serbia. Isolates originating from quince, tomato, and orange fruits, onion bulbs, and potato tubers were identified and characterized on a morphological, physiological, and molecular level. Morphological and physiological examination included observing micromorphology, testing growth on six different media and at five different temperatures, and production of three enzymes. Molecular identification and characterization were performed using four molecular markers: internal transcribed spacer, ß-tubulin, calmodulin, and DNA-dependent RNA polymerase II second largest subunit. The results of morphological and molecular analyses were in agreement, and they proved that the obtained isolates are T. minioluteus. In the pathogenicity assay, T. minioluteus was confirmed as a pathogen of all species tested with the exception of potato tubers. This is the first report of T. minioluteus as a postharvest plant pathogen on quince, tomato, and orange fruit and onion bulbs. Also, this is the first record of T. minioluteus in Serbia.

In vitro biodegradation potential of airborne Aspergilli and Penicillia.

The study addresses in vitro degradation potential of airborne Aspergillus and Penicillium/Talarmyces species originating from cultural heritage conservation premises. A series of rapid, cost effective biodegradation assays were performed to assess production of extracellular pigments, acids, and enzymes. Most of the isolates have demonstrated positive growth in at least one of the preformed tests. Strongest overall degradation potential was demonstrated for Penicillium brevicompactum, P. glabrum, and Talaromyces sayulitensis while Aspergillus domesticus, A. penicillioides, A. pseudoglaucus, and A. ruber did not exhibit positive reaction in any of the employed assays. Majority of isolates exhibited proteolytic and cellulolytic activity while carbonate dissolution was observed for only five tested fungi. Highest alteration of pH value in liquid media was documented for T. sayulitensis while A. niger and P. expansum exhibited strongest acid production on CREA. Certain isolates, mostly Penicillium species, displayed production of extracellular pigments. The results imply that many of the tested fungi have significant biodegradation capacity, indicating their potential to inflict structural and esthetic alterations on cultural heritage objects.

Phenol-based millipede defence: antimicrobial activity of secretions from the Balkan endemic millipede Apfelbeckia insculpta (L. Koch, 1867) (Diplopoda: Callipodida).

Millipedes use an array of chemical compounds to defend themselves from predator attack. These chemical substances can have additional roles, i.e. defence against various pathogens. We evaluated the efficacy of the defensive secretion of Apfelbeckia insculpta (L. Koch, 1867) against bacteria, yeasts, and filamentous fungi. The tested secretion consisted of two compounds, p-cresol and phenol, and showed antibacterial, antibiofilm, and antifungal potential against all selected microorganisms. The most sensitive bacterium in our study was Pseudomonas aeruginosa, while the tested defensive secretion manifested the lowest activity against Escherichia coli. The defensive secretion of A. insculpta also showed an ability, albeit mild, to suppress biofilm formation by P. aeruginosa. Among the tested yeasts, Candida albicans and C. krusei were the most susceptible and most resistant species, respectively. Finally, the concentration of extracts obtained from the tested defensive secretion needed to achieve an antifungal effect was lowest in the case of Cladosporium cladosporioides. Fusarium verticillioides and Penicillium rubens were the micromycetes most resistant to the tested secretion. Our results indicate that antibacterial activity of the defensive secretion of A. insculpta is similar to or slightly weaker than that of streptomycin, while comparison with antimycotics showed that the tested millipede secretion has stronger activity than fluconazole, but weaker activity than nystatin and ketoconazole. The present study corroborates previous findings indicating that the defensive secretions of millipedes can have different roles apart from antipredator protection and are effective against pathogenic microorganisms.

Neuroprotective Potential and Chemical Profile of Alternatively Cultivated Ganoderma lucidum Basidiocarps.

Various neurodegenerative diseases are the main challenges to the modern medicine and there is a great need for novel, natural, neuroprotective agents. Ganoderma lucidum is a well-known medicinal mushroom, which health benefits have been confirmed by numerous studies. As demand for its basidiocarps is increased and traditional cultivation on hardwoods is not environmentally friendly and economically justified, finding of alternative substrates is necessary. The aim of the study was to assess the effect of alternative cultivation substrates on the chemical profile of G. lucidum basidiocarps and their capacity to inhibit acetylcholinesterase and tyrosinase, which higher activity is directly associated with neurodegenerative processes. Extracts of basidiocarps cultivated on alternative substrates, especially on clear wheat straw, showed significantly higher inhibition capacities than extracts of commercially-grown ones. These extracts were considerably different chemically from commercial basidiocarps extracts and even nine new compounds were isolated from them. Our results suggest that cultivation substrate greatly affect the chemical profile and neuroprotective capacity of obtained basidiocarps and wheat straw is a promising cultivation substrate.

Potential of selected fungal species to degrade wheat straw, the most abundant plant raw material in Europe.

BACKGROUND: Structural component of plant biomass, lignocellulose, is the most abundant renewable resource in nature. Lignin is the most recalcitrant natural aromatic polymer and its degradation presents great challenge. Nowadays, the special attention is given to biological delignification, the process where white-rot fungi take the crucial place owing to strong ligninolytic enzyme system. However, fungal species, even strains, differ in potential to produce high active ligninolytic enzymes and consequently to delignify plant biomass. Therefore, the goals of the study were characterization of Mn-oxidizing peroxidases and laccases of numerous mushrooms as well as determination of their potential to delignify wheat straw, the plant raw material that, according to annual yield, takes the first place in Europe and the second one in the world. RESULTS: During wheat straw fermentation, Lentinus edodes HAI 858 produced the most active Mn-dependent and Mn-independent peroxidases (1443.2 U L-1 and 1045.5 U L-1, respectively), while Pleurotus eryngii HAI 711 was the best laccase producer (7804.3 U L-1). Visualized bends on zymogram confirmed these activities and demonstrated that laccases were the dominant ligninolytic enzymes in the studied species. Ganoderma lucidum BEOFB 435 showed considerable ability to degrade lignin (58.5%) and especially hemicellulose (74.8%), while the cellulose remained almost intact (0.7%). Remarkable selectivity in lignocellulose degradation was also noted in Pleurotus pulmonarius HAI 573 where degraded amounts of lignin, hemicellulose and cellulose were in ratio of 50.4%:15.3%:3.8%. CONCLUSIONS: According to the presented results, it can be concluded that white-rot fungi, due to ligninolytic enzymes features and degradation potential, could be important participants in various biotechnological processes including biotransformation of lignocellulose residues/wastes in food, feed, paper and biofuels.

Antifungal activity of the pygidial gland secretion of Laemostenus punctatus (Coleoptera: Carabidae) against cave-dwelling micromycetes.

The antifungal potential of the pygidial gland secretion of the troglophilic ground beetle Laemostenus punctatus from a cave in Southeastern Serbia against cave-dwelling micromycetes, isolated from the same habitat, has been investigated. Eleven collected samples were analyzed and 32 isolates of cave-dwelling fungi were documented. A total of 14 fungal species were identified as members of the genera Aspergillus, Penicillium, Alternaria, Cladosporium, Rhizopus, Trichoderma, Arthrinium, Aureobasidium, Epicoccum, Talaromyces, and Fusarium. Five isolates were selected for testing the antifungal activity of the pygidial gland secretion: Talaromyces duclauxi, Aspergillus brunneouniseriatus, Penicillium sp., Rhizopus stolonifer, and Trichoderma viride. The microdilution method has been applied to detect minimal inhibitory concentrations (MICs) and minimal fungicidal concentrations (MFCs). The most sensitive isolate was Penicillium sp., while the other isolates demonstrated a high level of resistance to the tested agent. L. punctatus has developed a special mechanism of producing specific compounds that act synergistically within the secretion mixture, which are responsible for the antifungal action against pathogens from the cave. The results open opportunities for further research in the field of ground beetle defense against pathogens, which could have an important application in human medicine, in addition to the environmental impact, primarily.

Fungal-Induced Deterioration of Mural Paintings: In Situ and Mock-Model Microscopy Analyses.

Fungal deterioration of frescoes was studied in situ on a selected Serbian church, and on a laboratory model, utilizing standard and newly implemented microscopy techniques. Scanning electron microscopy (SEM) with energy-dispersive X-ray confirmed the limestone components of the plaster. Pigments used were identified as carbon black, green earth, iron oxide, ocher, and an ocher/cinnabar mixture. In situ microscopy, applied via a portable microscope ShuttlePix P-400R, proved very useful for detection of invisible micro-impairments and hidden, symptomless, microbial growth. SEM and optical microscopy established that observed deterioration symptoms, predominantly discoloration and pulverization of painted layers, were due to bacterial filaments and fungal hyphal penetration, and formation of a wide range of fungal structures (i.e., melanized hyphae, chlamydospores, microcolonial clusters, Cladosporium-like conidia, and Chaetomium perithecia and ascospores). The all year-round monitoring of spontaneous and induced fungal colonization of a "mock painting" in controlled laboratory conditions confirmed the decisive role of humidity level (70.18±6.91% RH) in efficient colonization of painted surfaces, as well as demonstrated increased bioreceptivity of painted surfaces to fungal colonization when plant-based adhesives (ilinocopie, murdent), compared with organic adhesives of animal origin (bone glue, egg white), are used for pigment sizing.

Antigenotoxic Effect of Trametes spp. Extracts against DNA Damage on Human Peripheral White Blood Cells.

Trametes species have been used for thousands of years in traditional and conventional medicine for the treatment of various types of diseases. The goal was to evaluate possible antigenotoxic effects of mycelium and basidiocarp extracts of selected Trametes species and to assess dependence on their antioxidant potential. Trametes versicolor, T. hirsuta, and T. gibbosa were the species studied. Antigenotoxic potentials of extracts were assessed on human peripheral white blood cells with basidiocarp and mycelium extracts of the species. The alkaline comet test was used for detection of DNA strand breaks and alkali-labile sites, as well as the extent of DNA migration. DPPH assay was used to estimate antioxidative properties of extracts. Fruiting body extracts of T. versicolor and T. gibbosa as well as T. hirsuta extracts, except that at 20.0 mg/mL, were not genotoxic agents. T. versicolor extract had at 5.0 mg/mL the greatest antigenotoxic effect in both pre- and posttreatment of leukocytes. The mycelium extracts of the three species had no genotoxic activity and significant antigenotoxic effect against H2O2-induced DNA damage, both in pre- and posttreatment. The results suggest that extracts of these three species could be considered as strong antigenotoxic agents able to stimulate genoprotective response of cells.

Aspergilli Response to Benzalkonium Chloride and Novel-Synthesized Fullerenol/Benzalkonium Chloride Nanocomposite.

A comprehensive comparative analysis of antifungal potential of benzalkonium chloride and newly synthesized fullerenol/benzalkonium chloride nanocomposite was conducted to assess the possible impact of carbon-based nanocarrier on antimicrobial properties of the commonly used biocide. Physical characterization of synthesized nanocomposite showed zeta potential of +37.4 mV and inhomogeneous particles size distribution, with nanocomposite particles' dimensions within 30-143 nm and maximum number of particles at 44 nm. The effect of pure and fullerenol nanocarrier-bound biocide was evaluated in eight Aspergillus species. In mycelial growth assay, nanocomposite was more potent, as fungicidal effect of 1.04/0.6 µg mL(-1) was obtained in all but one of the isolates (A. niger), while proportional concentration of pure biocide (0.6 µg mL(-1)) completely inhibited mycelial growth of only three Aspergillus species. However, conidia appear to be less susceptible to nanocomposite treatment, as lower fungistatic (MIC) and fungicidal (MFC) concentrations were obtained with biocide alone (MIC in range from 0.03 to 0.15 µg mL(-1) and MFC from 0.075 to 0.45 µg mL(-1)). To a different degree, both substances stimulated aflatoxin B1 production and inhibited ochratoxin A synthesis. Very low mycelium biomass yield, in range from 1.0 to 3.0 mg dry weight, was documented in both biocide and nanocomposite enriched medium.

Fungicide sensitivity of Trichoderma spp. from Agaricus bisporus farms in Serbia.

Trichoderma species, the causal agents of green mould disease, induce great losses in Agaricus bisporus farms. Fungicides are widely used to control mushroom diseases although green mould control is encumbered with difficulties. The aims of this study were, therefore, to research in vitro toxicity of several commercial fungicides to Trichoderma isolates originating from Serbian and Bosnia-Herzegovina farms, and to evaluate the effects of pH and light on their growth. The majority of isolates demonstrated optimal growth at pH 5.0, and the rest at pH 6.0. A few isolates also grew well at pH 7. The weakest mycelial growth was noted at pH 8.0-9.0. Generally, light had an inhibitory effect on the growth of tested isolates. The isolates showed the highest susceptibility to chlorothalonil and carbendazim (ED50 less than 1 mg L(-1)), and were less sensitive to iprodione (ED50 ranged 0.84-6.72 mg L(-1)), weakly resistant to thiophanate-methyl (ED50 = 3.75-24.13 mg L(-1)), and resistant to trifloxystrobin (ED50 = 10.25-178.23 mg L(-1)). Considering the toxicity of fungicides to A. bisporus, carbendazim showed the best selective toxicity (0.02), iprodione and chlorothalonil moderate (0.16), and thiophanate-methyl the lowest (1.24), while trifloxystrobin toxicity to A. bisporus was not tested because of its inefficiency against Trichoderma isolates.

Potential of Pleurotus ostreatus mycelium for selenium absorption.

The aim of this study was to evaluate the effect of high selenium (Se) concentrations on morphophysiological and ultrastructural properties of Pleurotus ostreatus. Mycelium growth was good in media enriched with 5.0, 10.0, and 20.0 mg L(-1) of Se, concentration of 500.0 mg L(-1) strongly inhibited growth, and 1000.0 mg L(-1) was the minimum inhibitory concentration. Contrary to thin-walled, hyaline, branched, and anastomized hyphae with clamp-connections in the control, at Se concentrations of 100.0 and 500.0 mg L(-1), they were noticeably short, frequently septed and branched, with a more intensive extracellular matrix, and without clamp-connections. At high Se concentrations, hyphae with intact membrane, without cellular contents, with a high level of vacuolization, and with numerous proteinaceous bodies were observed. Biomass yield ranged between 11.8 g L(-1), in the control, and 6.8 g L(-1), at an Se concentration of 100.0 mg L(-1), while no production was detected at a concentration of 500.0 mg L(-1). Se content in the mycelia reached a peak (938.9 µg g(-1)) after cultivation in the medium enriched with Se at the concentration of 20.0 mg L(-1), while the highest absorption level (53.25%) was found in the medium enriched with 5.0 mg L(-1) Se.

Oxidative stress and species of genus Ganoderma (higher Basidiomycetes).

Oxidative stress, which is a factor in the aging process and in a series of serious disorders, arises when the reactive oxygen or nitrogen species are produced in excess and the capacity of cellular antioxidant defense is insufficient to detoxify and remove them. An internal antioxidant system is not always active enough to protect the human body from oxidative stress and, therefore, it needs the help of either synthetic or natural antioxidants. Nowadays, there is a growing interest in the substitution of synthetic antioxidants, which could have toxic and mutagen effects, with natural antioxidants. Recent studies revealed that besides their high nutritional value, mushrooms have great potential as antioxidant agents. Species of the genus Ganoderma, especially G. lucidum, are well-known medicinal mushrooms that traditionally are used in the prevention and treatment of many diseases and possess appreciable antioxidant potential.

Morpho-physiological diversity between Lingzhi or Reishi medicinal mushroom Ganoderma lucidium (W. Curt.:Fr.) P. Karst. and G. carnosum pat.

Two weakly differentiated taxa, Ganoderma lucidum and G. carnosum, were compared in their sufficient morphological and physiological features. The obtained results showed that dimensions of basidiospores and pileocystidia were insignificantly different, while pore shape and dimensions have shown greater diversity with average diameter of 138.46 µm in G. carnosum and 238.34 µm in G. lucidum. Mycelial growth rate was higher in G. lucidum (8.39 mm day-1) than in G. carnosum (6.02 mm day-1). G. lucidum was also a slightly better producer of biomass and extracellular polysaccharides (28.16 g L-1 and 1.42 mg mL-1, respectively) than G. carnosum (23.68 g L-1 and 0.35 mg mL-1, respectively). However, a higher amount of synthesized intracellular polysaccharides was noted in G. carnosum than in G. lucidum (40.00 mg g-1 and 30.00 mg g-1 of dry biomass, respectively). Higher activity levels of Mn-oxidizing peroxidases were obtained in G. carnosum, while G. lucidum was a better laccase producer. In G. carnosum, corn stem/NH4NO3 medium with nitrogen concentration of 20 mM was the optimum for Mn-dependent peroxidase production (88.00 U L-1), while the highest versatile peroxidase activity was detected in the medium with grapevine sawdust and 10 mM of nitrogen (80.80 U L-1). Wheat straw was the best carbon source for laccase synthesis in G. lucidum (55.75 U L-1).

A comparative assessment of the potential of polysaccharide production and intracellular sugar composition within Lingzhi or Reishi medicinal mushroom, Ganoderma lucidum (W.Curt.:Fr.)P. Karst. (Aphyllophoromycetideae).

Ganoderma lucidum is a well-known medicinal mushroom species in which polysaccharides are one of the major sources of biological activity. The species was considered as a species-complex due to significant variations in morphological, biochemical, and genetic features among populations with a worldwide distribution. This fact was the basis for setting the aim of this research: to study intraspecific diversity in polysaccharide production and intracellular sugar composition among selected G. lucidum strains. The presence ofintraspecific diversity among 10 G. lucidum strains, from different areas worldwide, was noted. Values of produced mycelia biomass and intracellular polysaccharides were found in wide ranges (3.1 - 28.2 g L(-1) and 20.0 - 53.3 mg g(-1), respectively), while differences in extracellular polysaccharide amounts were minor (0.2 - 1.5 mg mL(-1)). The significant quantitative and qualitative differences in intracellular sugar composition were noted. Glucose was the predominant sugar in almost all strains except one (HAI 447), where sucrose was dominant. The potential of polysaccharide production and intracellular sugar composition could be one more taxonomic criterion for strain characterization within G. lucidum. The differences in intracellular sugar composition and proportions could be reflected in features of produced polysaccharides and also in their biological activities.

Antioxidant properties of some lichen species.

Antioxidant activity of the acetone, methanol and aqueous extracts of the lichens Cladonia furcata, Hypogymnia physodes, Lasallia pustulata, Parmelia caperata and Parmelia sulcata has been screened in vitro by using different methods (DPPH radical scavenging, superoxide anion radical scavenging, reducing power, determination of total phenolic compounds and determination of total flavonoid content). Of the lichens tested, Lasallia pustulata had powerful antioxidant activities. Acetone, methanol and aqueous extracts of this lichen showed 90.93, 69.87 and 65.08% DPPH radical scavenging activities. Moreover, the tested extracts had effective reducing power and superoxide anion radical scavenging. Those various antioxidant activities were compared to standard antioxidants such as ascorbic acid, butylated hydroxyanisole (BHA) and α-tocopherol. In addition, total content of phenol and flavonoid in extracts were determined as pyrocatechol equivalent, and as rutin equivalent, respectively. The strong relationships between total phenolic and flavonoid contents and the antioxidative activities of tested extracts suggest that these compounds play important role in antioxidant activity. The present stady shows that tested lichen species demonstrated a strong antioxidant activity and can be considered as good sources of natural antioxidants.

Obtaining Cellulose-Available Raw Materials by Pretreatment of Common Agro-Forestry Residues With Pleurotus spp.

The goals of the present study were to characterize the profile of ligninolytic enzymes in five Pleurotus species and determine their ability to delignify eight common agro-forestry residues. Generally, corn stalks were the optimal inducer of Mn-dependent peroxidase activity, but the activity peak was noted after wheat straw fermentation by P. eryngii (3066.92 U/L). P. florida was the best producer of versatile peroxidase, especially on wheat straw (3028.41 U/L), while apple sawdust induced the highest level of laccase activity in P. ostreatus (49601.82 U/L). Efficiency of the studied enzymes was expressed in terms of substrate dry matter loss, which was more substrate-than species-dependent. Reduction of substrate dry mass ranged between 24.83% in wheat straw and 8.83% in plum sawdust as a result of fermentation with P. florida and P. pulmonarius, respectively. The extent of delignification of the studied substrates was different, ranging from 51.97% after wheat straw fermentation by P. pulmonarius to 4.18% in grapevine sawdust fermented by P. ostreatus. P. pulmonarius was also characterized by the highest cellulose enrichment (6.54) and P. ostreatus by very low one (1.55). The tested biomass is a highly abundant but underutilized source of numerous value-added products, and a cocktail of ligninolytic enzymes of Pleurotus spp. could be useful for its environmentally and economically friendly transformation.