Valorization of spent oyster mushroom substrate and laccase recovery through successive solid state cultivation of Pleurotus, Ganoderma, and Lentinula strains

Spent mushroom substrate (SMS) of Pleurotus ostreatus was supplemented with wheat bran and soybean flour in various proportions to obtain C/N ratios of 10, 20, and 30, and their effect was evaluated in successive cultivation of Pleurotus ostreatus, Pleurotus pulmonarius, Ganoderma adspersum, Ganoderma resinaceum, and Lentinula edodes strains with respect to mycelium growth rate, biomass concentration, recovery of the enzyme laccase and crude exopolysaccharides, and also with additional fruiting body production. All fungi showed the highest growth rate on unamended SMS (C/N 30), with G. resinaceum being the fastest colonizer (Kr = 9.84 mm day-1), while biomass concentration maximized at C/N 10. Moreover, supplementation affected positively laccase activity, with P. pulmonarius furnishing the highest value (44,363.22 U g-1) at C/N 20. On the contrary, L. edodes growth, fruiting, and laccase secretion were not favored by SMS supplementation. Fruiting body formation was promoted at C/N 30 for Ganoderma and at C/N 20 for Pleurotus species. Exopolysaccharide production of further studied Pleurotus strains was favored at a C/N 20 ratio, at the initial stage of SMS colonization. The obtained results support the potential effective utilization of supplemented SMS for laccase production from Ganoderma spp. and for new fruiting body production of Pleurotus spp.

Removal of Disperse Red 60 dye from aqueous solution using free and composite fungal biomass of Lentinus concinnus

Lentinus concinnus biomass was immobilized to carboxyl derivative of cellulose, carboxymethyl cellulose (CMC), in the presence of FeCl3 (0.1 mol L−1) via ionic cross-linking. The beads containing immobilized fungal biomass were incubated at 30 °C for three days to permit growth of the fungus. The free and immobilized fungal biomass were tested for adsorption of Disperse Red 60 (DR-60) from aqueous solution using bare CMC beads as a control system. The maximum adsorption of DR-60 on the free and immobilized fungal biomass was observed at pH 6.0. The adsorption of DR-60 by the free, and immobilized fungal biomass increased as the initial concentration of DR-60 in the medium increased up to 100 mg/L. The maximum adsorption capacity of the CMC beads, the free and immobilized fungal biomass (i.e. composite beads) were found to be 43.4, 65.7, and 92.6 mg g−1 dry sorbents, respectively. The equilibrium of the adsorption system was well described by Langmuir and Temkin isotherm models. Adsorption equilibrium was established in about 1.0 h. The adsorption of DR-60 on the fungal preparations followed pseudo-second-order kinetic model. It was observed that the immobilized fungal biomass has a high potential for the removal of DR-60 as a model dye from aqueous solution.

[Antioxidant Effect on the Growth And Formation of Lipids in the Fungus Lentinus tigrinus Growing on Medium with Lignosulfonate]

The addition of an antioxidant (2-ethyl-6-methyl-3-hydroxypyridine hydrochloride) to a culture of the fungus Lentinus tigrinus growing on a medium with lignosulfonate inhibited growth and changed the composition of cell phospholipids. The ratio of lipid messengers also changed, the phosphatidic acid level decreased, and the content of phosphatidylinositol dramatically increased. The substitution of lignosulfonate with glucose and the addition of an antioxidant increased the biomass yield of L. tigrinus, as well as that of another fungus, Cunninghamella japonica, which was incapable of biodegrading the biopolymer. The obtained results indicate the specificity of growth processes in the presence of lignosulfonate and confirm the role of free radical oxidation reactions in the biodegradation of this biopolymer by L. tigrinus.

[Influence of lignin and oxygen on the growth and the lipid formation of the fungus Lentinus tigrinus]

During cultivation of the filamentous fungus Lentinus tigrinus on a medium containing lignin, a high oxygen content stimulated the growth of the fungus and contributed to the yield of lipids. A high content of phosphatidic acid and a reduction in the level of phosphatidylethanolamine and phosphatidylserine were first detected in the composition of phospholipids. Changes in the composition of neutral lipids, such as variation in the ratio of esterified and free sterols, have occurred; thus, the amount of sterol esters reduced simultaneously with a decrease in the content of free fatty acids. Based on the obtained results, the possible role of phosphatidic acid as a second messenger in the process of the consumption of lignin by the fungus Lentinus tigrinus is discussed.

Biodegradation potential and ligninolytic enzyme activity of two locally isolated Panus tigrinus strains on selected agro-industrial wastes

The degradation potential and ligninolytic enzyme production of two isolated Panus tigrinus strains (M609RQY and M109RQY) were evaluated in this study. These strains were grown on three selected abundant agro-industrial wastes (rice straw; rice husk and cassava peel) under solid-state fermentation conditions. Degradation potential was determined by analyzing the chemical composition of the selected substrates before and after fermentation along with ligninolytic enzyme production. The strain M609RQY led to the highest lignin degradation of 40.81% on cassava peel, 11.25% on rice husk and 67.96% on rice straw. Both strains significantly increased the protein content of cassava peel. Rice husk stimulated maximum laccase (2556 U/L) and lignin peroxidase (24 U/L) production by the strains M109RQY and M609RQY, respectively. Furthermore, cassava peel stimulated maximum manganese-dependent peroxidase (141 U/L) production by the strain M109RQY. The de-lignified rice straw and the nutritionally-improved cassava peel could serve as potential animal feed supplements.

Lentinus (Panus) tigrinus augmentation of a historically contaminated soil: matrix decontamination and structure and function of the resident bacterial community

The ability of Lentinus tigrinus to grow and to degrade persistent aromatic hydrocarbons in aged contaminated soil was assessed in this study. L. tigrinus extensively colonized the soil; its degradation activity after 60 d incubation at 28°C, however, was mostly limited to dichloroaniline isomers, polychlorinated benzenes and diphenyl ether while the fungus was unable to deplete 9,10-anthracenedione and 7-H-benz[DE]anthracene-7-one which were the major soil contaminants. Although clean-up levels were limited, both density of cultivable heterotrophic bacteria and richness of the resident bacterial community in L. tigrinus microcosms (LtM) increased over time to a significantly larger extent than the respective amended incubation controls (1.9×10(9) CFU g(-1) vs. 1.0×10(9) CFU g(-1) and 37 vs. 16, respectively). Naphthalene- and catechol 2,3-dioxygenase gene copy numbers, however, decreased over time at a higher rate in LtM than in incubation controls likely due to a higher stimulation on heterotrophs than xenobiotics-degrading community members.

[The role of laccase and peroxidase of Lentinus (Panus) tigrinus fungus in biodegradation of high phenol concentrations in liquid medium]

The possibility of the usage of Lentinus tigrinus fungus strain VKM F-3616D for biodegradation of high (up to 5%) phenol concentrations in liquid medium and the involvement of laccase and peroxidase in this process have been studied. L. tigrinus fungus was demonstrated to effectively digrade phenol with easy biomass separation from the liquid. Decrease in phenol concentration was accompanied by increased secretion level and laccase activity at the preliminary stages of biodegradation, while that of peroxidase was at the latest stages of biodegradation. These enzyme secretions in distinct ratios and consequences are necessary for effective phenol biodegradation. An effective approach for phenol concentration decrease in the waste water of smoking shops in meat-processing factories using L. tigrinus fungus was described.

Change in phospholipid composition and phospholipase activity of the fungus Lentinus tigrinus VKM F-3616D during growth in the presence of phenol and lignocellulosic substrates

Changes in phospholipid composition, phospholipase activity, and accumulation of lipid peroxidation products in mycelium of the lignin-degrading fungus Lentinus (Panus) tigrinus VKM F-3616D in the presence of phenol and lignocellulosic substrates in the cultivation medium are reported. It is shown that in fungal mycelium in the presence of both substrates the share of lysophosphatidylcholine sharply increases. The parity between separate groups of phosphatidylinositols also changes. The lysophosphatidylcholine content increase during cultivation is connected with activation of phospholipase A(2) (EC 3.1.1.4), and phosphatidylinositol parity change is associated with distinctions in affinity of phosphoinositide-specific phospholipase C (EC 3.1.4.11) to them.

[The effect of copper ions on the production of laccase by the fungus Lentinus (Panus) tigrinus]

The basidiomycete Lentinus tigrinus was cultured in media containing copper ions added at different growth stages. Copper ions at increased concentrations decelerated of the fungal biomass accumulation. The later Cu2+ ions were added, the better the fungal mycelium developed, and the toxic effect of Cu2+ was less pronounced. The maximum laccase activity (47 U/ml) was observed in the presence of 1.5-2.0 mM Cu2+ added on day 4 of cultivation.

[Increased secretion of lignolytic enzymes by the Lentinus tigrinus fungus after addition of butanol and toluene in submerged cultivation]

We studied the effects of butanol and toluene on secretion of lignolytic enzymes by the Lentinus tigrinus fungus during submerged cultivation. Addition of butanol and toluene during the trophophase was followed by an increase in laccase and peroxidase activity of the culture and change in the composition of phospholipids and fatty acids. The ratio of phosphatidylcholine and phosphatidic acid decreased, while the amount of lysophosphatidylcholine, phosphatidylethanolamine, phosphoinositides, phosphatidylserine, and unsaturated fatty acids decreased. These changes resulted in an increase in the unsaturation index.

Evaluation of waste mushroom logs as a potential biomass resource for the production of bioethanol

In order to investigate the possibility of using waste mushroom logs as a biomass resource for alternative energy production, the chemical and physical characteristics of normal wood and waste mushroom logs were examined. Size reduction of normal wood (145 kW h/tone) required significantly higher energy consumption than waste mushroom logs (70 kW h/tone). The crystallinity value of waste mushroom logs was dramatically lower (33%) than normal wood (49%) after cultivation by Lentinus edodes as spawn. Lignin, an enzymatic hydrolysis inhibitor in sugar production, decreased from 21.07% to 18.78% after inoculation of L. edodes. Total sugar yields obtained by enzyme and acid hydrolysis were higher in waste mushroom logs than in normal wood. After 24h fermentation, 12 g/L ethanol was produced on waste mushroom logs, while normal wood produced 8 g/L ethanol. These results indicate that waste mushroom logs are economically suitable lignocellulosic material for the production of fermentable sugars related to bioethanol production.

Factors influencing the production of water-soluble endopolysaccharides and exopolysaccharides from Lentinus lepideus and their effects on immune cytokine production

An efficient method to produce water-soluble polysaccharides from Lentinus lepideus is described. The productivity of both endopolysaccharides (PPS) and exopolysaccharides (EPS) was compared under various culture conditions. The effect of treating their own PPS and EPS on immune cytokine production was also studied in relation to culture factors. High yield production of EPS required moderate culture temperature (25 degrees ) as well as long culture period (16-20 days). In contrast, PPS production required high culture temperature (30 degrees ) and short culture period ( days). Most of the carbon sources did not affect polysaccharides and mycelial production except for sucrose. Immune cytokine levels in the EPS treatment varied among carbon sources or culture periods. PPS did not appear to affect much on the production of cytokines, regardless of the culturing factors, except for the culture period. These results suggest that the optimal culture conditions for L. lepideus vary according to culture purposes, and different culture conditions should be used for different targets including mycelial biomass, EPS, and PPS. Whereas the immunomodulating activity of EPS appeared to be affected by culture conditions in L. lepideus, that of PPS did not.

Optimal conditions for the fruit body production of natural occurring strains of Lentinus tigrinus

Lentinus tigrinus is a species with a fleshy pileus, strong odor and agreeable taste. In order to determine the optimal conditions for the production of this species, three substrates based on Salix sp. sawdust, wheat straw and supplements were tested in 500g dry weight bags at two different fruiting temperatures. Naturally occurring strains of this species were incubated at 30 degrees C. Primordium initiation could be observed 11-16 days after induction conditions began. This species produced highest yields with biological efficiency (BE) of 62% with supplemented sawdust at 25 degrees C. When bags were reduced to 100g dry weight, spawning run time was reduced from 28 to 30 to 10 to 14 days and BE increased more than 100%. L. tigrinus is a promising species with possibilities for commercial production.

[Determination of the parameters for producing a biobinder from wood: a mathematical modeling of the transformation of lignocellulose substrate by the fungus Panus tigrinus]

A biochemical scheme for the transformation of wood lignocellulose during enzymatic hydrolysis of polysaccharides and lignin destruction in reactions involving free radicals was developed, and a corresponding mathematical model was constructed. Processing (fermentation) of wood particles by the fungus Panus tigrinus in a submerged culture for producing a biobinder of wood composites--woodchip boards and fiber-boards--is considered. The mathematical model was used to study the technological parameters that influence the production of enzymes and fungal biomass and the level of free radical accumulation in the substrate, i.e., the factors determining the production of the biobinder. The optimal values of these parameters were determined, namely: the specific surface of wood particles, amounting to 2000 cm2/g; processing time of 56 h; and an initial concentration of 3.0 g/l of fungal biomass in the submerged culture.

[Interrelation between the composition of lipids and products of their peroxidation and the secretion of ligninolytic enzymes during growth of Lentinus (Panus) tigrinus]

Lipid composition, intracellular products of lipid peroxidation (LPO), and the activities of extracellular enzymes were studied during submerged cultivation of the xylotrophic fungus Lentinus (Panus) tigrinus VKM F-3616D. The maximum secretion of ligninolytic enzymes during the phase of active mycelium growth correlated with increased content of readily oxidized phospholipids and unsaturated fatty acids and with low content of the LPO products. In the idiophase, which was characterized by lower excretion of extracellular ligninolytic enzymes, the content of more stable phospholipids, saturated fatty acids, and LPO products increased. A relationship between the composition of mycelial lipids and the secretion of ligninolytic enzymes was revealed.

Developmental regulator Le.CDC5 of the mushroomLentinula edodes: analyses of its amount in each of the stages of fruiting-body formation and its distribution in parts of the fruiting bodies

Immunoblot analysis of Le.CDC5 (842 amino acid residues), the expressed product of the cDNA of Le.cdc5 gene that has been previously reported to be most actively transcribed in primordia and small immature fruiting bodies of the basidiomycete Lentinula edodes, showed that the primordia, immature fruiting bodies and mature fruiting bodies contain similar amounts of Le.CDC5 protein. This indicates that the Le.CDC5 protein molecules synthesized in the beginning and early stage of fruiting-body formation remains in mycelial tissues even after small immature fruiting bodies developed and matured. Immunohistochemical analysis showed that Le.CDC5 is present everywhere in the mycelial tissues of immature fruiting body, but prehymenophore, the border between pileus and stipe, and the bottom of stipe seem likely to contain larger amounts of Le.CDC5. Within the hymenophore of mature fruiting body, the hymenium (in/on which a large number of basidia and basidiospores are formed) contains the Le.CDC5 most exclusively.

Modification of surface properties of Lentinus sajor-caju mycelia by physical and chemical methods: evaluation of their Cr6+ removal efficiencies from aqueous medium

The hexavalent chromium biosorption onto untreated and heat-, acid- and alkali-treated Lentinus sajor-caju mycelia were studied from aqueous solutions. The particles sizes of the fungal mycelia ranged from 100 to 200 microm. The effect of pH, temperature, biosorbent dose, initial concentration of chromium ions, contact time parameters were investigated in a batch system. Biosorption equilibrium was established in about 4 h. The surface charge density of the fungal preparations varied with pH, and the maximum absorption of chromium ions on the fungal preparations were obtained at pH 2.0. The biosorption of chromium ions by the tested fungal preparations increased as the initial concentration of chromium ions increased in the medium. The maximum biosorption capacities of the untreated and heat, HCl- and NaOH-treated fungal biomass were 0.363, 0.613, 0.478 and 0.513 mmol Cr6+ per gram of dry biomass, respectively. The correlation regression coefficients and the Langmuir constant values show that the biosorption process can be well defined by Langmuir equation. The chromium adsorption data were analysed using the first- and the second-order kinetic models. The first-order equation is the most appropriate equation to predict the biosorption capacities of all the fungal preparations. In addition, the polarity and surface energy of the untreated and all the modified biomass film preparations were determined by contact angle measurement. All the tested fungal biomass preparations could be regenerated using 0.1 M NaOH solution.

[Effect of wood modification on lignin consumption and synthesis of lignolytic enzymes by the fungus Panus (Lentinus) tigrinus]

Lignin consumption and synthesis of lignolytic enzymes by the fungus Panus (Lentinus) tigrinus cultivated on solid phase (modified and unmodified birch and pine sawdusts) were studied. The fungus grew better and consumed more readily the birch lignin than the pine wood. Peroxidase activity was higher in the case of pine sawdust; laccase and lignolytic activities, in the case of birth sawdust. Treatment with ammonia or sulfuric acid decreased lignin consumption by the fungus cultivated on either medium. Modification of sawdust by ultrasound increased lignin consumption and may be recommended for accelerating biodegradation of lignocellulose substrates.

Effects of certain heavy metals on the growth, dye decolorization, and enzyme activity of Lentinula edodes

Various physiological parameters of Lentinula edodes (Shiitake) in the presence of nine heavy metal salts were investigated. The mycelial growth was highly sensitive to cadmium and mercury, but less sensitive to zinc, copper, and lead. This resistance can be particularly dangerous to humans in the case of edible fungi such as Shiitake because of the possible heavy metal accumulation during growth and fruiting body production. All of the tested heavy metals inhibited decolorization of the dye Poly R-478 and the production of manganese peroxidase to a greater extent than they inhibited growth. Interestingly, with the exception of iron, the addition of all heavy metal salts investigated led to the increase of laccase production. Apart from cadmium and iron, none of the heavy metals inhibited the in vitro enzyme activities in concentrations up to 3mM. The results of this study indicated the applicability of L. edodes in biosorption technologies used in the removal of toxic metals from contaminated effluents and in bioremediation technologies designed to treat complex wastes contaminated with heavy metals in addition to other xenobiotics.

Lentinellus herbarum, a rediscovered unclamped species

The fungus first described as Lentinus flabelliformis var. herbarum has been found fruiting on dead Epilobium angustifolium stalks at La Chaise-Dieu (France), the first record since its original diagnosis. The basidiospore characters, trama and hymenium structure indicate the species belongs Lentinellus sect. Omphalodei (Hericiales), but the absence of clamps is a remarkable character, new for this genus. The new combination L. herbarum comb. nov. (syn. Lentinus flabelliformis var. herbarum) is made and a neotype designated. A key to the eight European taxa of sect. Omphalodei is included.

The synthesis of indole-3-acetic acid by the industrially important white-rot fungus Lentinus sajor-caju under different culture conditions

The synthesis of plant growth hormone auxin, indole-3-acetic acid (IAA), is not only confined to flowering plants. Yeasts and other fungi are also known to produce this hormone and in many cases at higher levels than plants. The main concern of this study was to determine the physical and chemical conditions necessary for optimal biosynthesis of this hormone by Lentinus sajor-caju. Glucose was determined to be superior to sucrose as carbon and energy source. The synthesis of IAA in a nitrogen-free medium or in a medium with low external phosphate was substantially reduced. Light exposed and non-agitated cultures grown in dark had also reduced levels of IAA compared to agitated cultures grown in dark. The highest (0.18 mg ml-1) IAA level was determined in cultures grown in glucose containing medium (pH 7.5) on a rotary shaker (150 rpm) at 30 degrees C in dark. The biological activity of IAA obtained from the extra-cellular culture of Lentinus sajor-caju was determined using oat coleptile growth test.

Changes in activity of extracellular enzymes in dual cultures of Lentinula edodes and mycoparasitic Trichoderma strains

AIMS

The main problem that arises during the cultivation of Lentinula edodes, the Asian Shiitake mushroom, is that the logs on which the cultivation is performed are contaminated by competing micro-organisms, especially Trichoderma spp. The aim of this study was to examine the changes in activity of extracellular enzymes in dual cultures of Trichoderma spp. and L. edodes.

METHODS AND RESULTS

Extracellular enzyme activities were determined spectrophotometrically. Trichoderma enzymes important for the degradation of fungal cell walls (N-acetyl-beta-glucosaminidase and laminarinase) were shown to be induced by inactive L. edodes mycelia in liquid culture. The changes that occurred in the extracellular enzyme activities of L. edodes and mycoparasitic Trichoderma spp. (T. aureoviride, T. harzianum and T. viride) were examined during antagonistic interactions on solid medium. The extracellular enzyme patterns of both partners proved to be altered. Trichoderma spp. were induced to produce N-acetyl-beta-glucosaminidase and laminarinase in the presence of active L. edodes mycelia, similarly as observed in liquid culture. The activities of both laccase and manganese peroxidase of L. edodes decreased after physical contact with active Trichoderma mycelia, possibly in consequence of the beginning of degradation of L. edodes by the Trichoderma enzymes. However, besides a decrease in manganese peroxidase activity, an enhancement of L. edodes laccase activity was observed on solid media containing crude culture fluids from Trichoderma liquid cultures. The metabolites responsible for these effects proved to be heat stable.

CONCLUSIONS

Induction and inhibition of several extracellular enzymes of both partners were shown in dual cultures of L. edodes and Trichoderma strains, indicating the important role of these enzymes in the antagonistic interaction between the two species.

SIGNIFICANCE AND IMPACT OF THE STUDY

As the main problem during the large-scale cultivation of L. edodes is the contamination of the growth substrate by Trichoderma mycelia, the particular knowledge of the mechanism of this competition might be relevant.

Transcriptional regulation of laccase and cellulase genes during growth and fruiting of Lentinula edodes on supplemented sawdust

Transcription of laccase and cellulase genes of Lentinula edodes was examined during growth and development under different temperature and moisture levels on a sawdust-based substrate. RNA was extracted from samples of mycelium and fruit bodies at various stages of development and gene expression was determined by competitive RT-PCR. The level of laccase transcripts was maximal during the mycelial growth stage, and then declined rapidly at the fruiting stage. In contrast, the cellulase transcript level peaked at the veil-break stage during fruit body development. Gene expressions for laccase and cellulase were triggered by microclimatic changes, specifically lower temperature and osmotic pressure.

Solid state cultivation--an efficient method to use toxic agro-industrial residues

Studies were carried out to screen twelve strains of Lentinus edodes for their efficiency to grow on toxic agro-industrial residues of coffee industry in solid state cultivation (SSC). Based on best mycelial growth (7.57 mm/day) and biomass production (48.78 mg/plate in 12 days at 24 degrees C) in coffee husk extract medium, a strain, L. edodes LPB 02 was selected for mushroom cultivation in SSC on coffee husk (treated and untreated), coffee spent ground, and a mixed-substrate comprising coffee husk and coffee spent ground (1:1). SSC was carried out under different conditions of moisture and spawn rate. Spawn rate of 10% and moisture level of 55-60% was found suitable for all the substrates. Treatment of the coffee husk with hot water was found useful for its utilization by the fungus. Results showed that there was an increase in the protein content and decrease in the fibre content of the substrates after SSC. Fruiting bodies were obtained from the treated coffee husk, spent ground and mixed-substrate, and the biological efficiency achieved was 85.8, 88.6 and 78.4% for these substrates, respectively. However, no fruiting body was obtained with raw coffee husk was used as the substrate. Results showed that after SSC, there was a decrease of about 27, 40 and 24% in caffeine and about 18, 49 and 12% in tannin contents in the treated coffee husk, coffee spent ground and mixed substrate, respectively. No caffeine or, tannins were found in fruiting body indicating their degradation by the fungal strain.

Decreased zinc ion accumulation by the basidiomycete Lentinus edodes over-expressing L. edodes PriA gene

The information that the deduced expression product of Lentinus edodes priA gene consists of N-terminal hydrophobic sequence, putative zinc-binding motifs and C-terminal membrane-binding-promoting unique sequence led us to analyze its function in L. edodes. Here L. edodes monokaryotic cells over-expressing priA gene were found to exhibit a remarkably decreased accumulation of zinc ion, indicating the involvement of the priA gene in regulation of the intracellular zinc concentration.

Molecular cloning, characterization, and differential expression of a glucoamylase gene from the basidiomycetous fungus Lentinula edodes

The complete nucleotide sequence of putative glucoamylase gene gla1 from the basidiomycetous fungus Lentinula edodes strain L54 is reported. The coding region of the genomic glucoamylase sequence, which is preceded by eukaryotic promoter elements CAAT and TATA, spans 2,076 bp. The gla1 gene sequence codes for a putative polypeptide of 571 amino acids and is interrupted by seven introns. The open reading frame sequence of the gla1 gene shows strong homology with those of other fungal glucoamylase genes and encodes a protein with an N-terminal catalytic domain and a C-terminal starch-binding domain. The similarity between the Gla1 protein and other fungal glucoamylases is from 45 to 61%, with the region of highest conservation found in catalytic domains and starch-binding domains. We compared the kinetics of glucoamylase activity and levels of gene expression in L. edodes strain L54 grown on different carbon sources (glucose, starch, cellulose, and potato extract) and in various developmental stages (mycelium growth, primordium appearance, and fruiting body formation). Quantitative reverse transcription PCR utilizing pairs of primers specific for gla1 gene expression shows that expression of gla1 was induced by starch and increased during the process of fruiting body formation, which indicates that glucoamylases may play an important role in the morphogenesis of the basidiomycetous fungus.

[Hemagglutinating activity of Lentinus edodes (Berk.) Sing [Lentinula edodes (Berk.) Pegler]]

The hemagglutinating (HA) activity of the submerged mycelium and the culture liquid (CL) of four strains of Lentinus edodes was studied. The HA activity of CLs proved to be much higher than that of mycelia. The carbohydrate specificity of fungal agglutinating factors was determined. HA activity was investigated as a function of the inoculum size, cultivation temperature, and culture age. The agglutinating activity of different morphogenetic structures of L. edodes F-249, including mycelium, brown mycelial mat (MM), primordia, and fruiting bodies, was studied, MM was found to possess the maximum HA activity, which can be explained by the possible involvement of agglutinins in the formation of MM, which is composed of glued hyphae.