Enhancement of polysaccharides production in <Emphasis Type="Italic">Ganoderma lucidum</Emphasis> by the addition of ethyl acetate extracts from <Emphasis Type="Italic">Eupolyphaga sinensis</Emphasis> and <Emphasis Type="Italic">Catharsius molossus</Emphasis>

To screen stimulators from Chinese medicinal insects for mycelial growth and polysaccharides production of Ganoderma lucidum, G. lucidum was inoculated into the media with and without supplementation of medicinal insect extracts. The ethyl acetate extract of Eupolyphaga sinensis at 55 mg l⁻¹ lead to significant increase in both biomass and intracellular polysaccharides (IPS) concentration from 8.53 ± 0.41 to 14.16 ± 0.43 and 1.28 ± 0.09 to 2.13 ± 0.11 g l⁻¹, respectively. In addition, the ethyl acetate extract of Catharsius molossus at 55 mg l⁻¹ significantly enhanced extracellular polysaccharides (EPS) production; the EPS yield increased from 350.9 ± 14.1 to 475.1 ± 15.3 mg l⁻¹. There were no new components in the two types of polysaccharides obtained by the addition of the insect extracts.     

<Emphasis Type="Italic">In vitro</Emphasis> propagation of Indian Kino (<Emphasis Type="Italic">Pterocarpus marsupium</Emphasis> Roxb.) using Thidiazuron

An efficient protocol was developed for micropropagation of an economically important timber-yielding multipurpose tree, Pterocarpus marsupium Roxb. Multiple shoots were induced from cotyledonary nodes (CNs) derived from 18-d-old axenic seedlings on Murashige and Skoog (MS) medium supplemented with thidiazuron (TDZ) (0.1–10 μM). The highest shoot regeneration frequency (90%) and maximum number (15.2 ± 0.20) of shoots per explant was recorded on MS medium amended with 0.4 μM TDZ. Continuous presence of TDZ inhibited shoot elongation. In the primary medium, TDZ-initiated cultures were transferred to the secondary medium supplemented with another cytokinin, 6-benzyladenine (BA), for shoot growth and elongation. Maximum (90%) shoot elongation with an average shoot length of 5.4 ± 0.06 cm was observed at 5 μM BA. To further enhance the number of shoots per explant, mother tissue was repeatedly subcultured on fresh shoot induction medium after each harvest of newly formed shoots. Thus, by adopting this strategy, an average of 44 shoots per explant could be obtained. About 65% of in vitro regenerated shoots produced a maximum number (4.4 ± 0.2) of roots per shoot by a two-step culture procedure employing pulse treatment and subsequent transfer of treated shoots to a low concentration of 0.2 μM indole-3-butyric acid along with phloroglucinol (3.96 μM). The in vitro-raised plantlets were successfully acclimatized first under culture room conditions, then to greenhouse with 70% survival rate.     

Morphological and Genetic Characterization of <Emphasis Type="Italic">Saimiri boliviensis</Emphasis>

The taxonomy of Saimiri is controversial because morphological characteristics, traditionally used for identification, are insufficient to distinguish species and subspecies. Genetic studies of specimens become relevant for captive management, especially considering their frequently unknown geographical origin. We analyzed phenotypic and genetic parameters in Saimiri spp. in Argentinean zoological gardens and biological stations to provide a more accurate taxonomic identification. We studied 27 males and 19 females of Saimiri spp. The cytogenetic analysis in mitotic metaphases corroborated a modal number of 2N = 44, XX/XY, and FN = 75 for males and FN = 76 for females. G- and C-bands, fluorescence in situ hybridization (FISH) and the pelage coloration pattern of all the specimens corresponded to Saimiri boliviensis boliviensis. We characterized for the first time the sperm cell morphology and morphometry (mean ± SE): total length: 71.39 ± 5.40 μm; head length: 5.71 ± 0.81 μm; head width: 3.76 ± 0.70 μm; acrosome length: 3.70 ± 0.82 μm; midpiece length: 12.20 ± 2.22 μm. Researchers can use the characterization of the sperm morphology as another parameter for taxonomic identification that, together with cytogenetic and molecular ones, would allow a more precise identification of individual Saimiri boliviensis boliviensis.     

Alginate production by <Emphasis Type="Italic">Pseudomonas mendocina</Emphasis> in a stirred draft fermenter

In this study alginate production by Pseudomonas mendocina in a laboratory-scale fermenter was investigated. In the experiments the effect of temperature (25–31°C) and agitation (500–620 rev min⁻¹) at a constant air flow of 10 v/v/h were evaluated in relation to the rate of glucose bioconversion to alginate using response surface methodology (RSM). The fermenter configuration was also adapted to a system with a screw mixer and draft tube, due to the change in rheological characteristics of the fermentation broth. The adjusted model indicates a temperature of 29.1°C and agitation of 553 rev min⁻¹ for optimum alginate synthesis. In this fermentation system a Y _p/s of 44.8% was achieved. The alginate synthesized by P. mendocina showed a partially acetylated pattern as previously reported for alginates obtained from other Pseudomonas spp and Azotobacter vinelandii.     

Preparation and <Emphasis Type="Italic">In Vitro</Emphasis>/<Emphasis Type="Italic">In Vivo</Emphasis> Evaluation of Microparticle Formulations Containing Meloxicam

In this study, we have formulated chitosan-coated sodium alginate microparticles containing meloxicam (MLX) and aimed to investigate the correlation between in vitro release and in vivo absorbed percentages of meloxicam. The microparticle formulations were prepared by orifice ionic gelation method with two different sodium alginate concentrations, as 1% and 2% (w/v), in order to provide different release rates. Additionally, an oral solution containing 15 mg of meloxicam was administered as the reference solution for evaluation of in vitro/in vivo correlation (ivivc). Following in vitro characterization, plasma levels of MLX and pharmacokinetic parameters [elimination half-life (t _1/2), maximum plasma concentration (C _max), time for C _max (t _max)] after oral administration to New Zealand rabbits were determined. Area under plasma concentration–time curve (AUC_0–∞) was calculated by using trapezoidal method. A linear regression was investigated between released% (in vitro) and absorbed% (in vivo) with a model-independent deconvolution approach. As a result, increase in sodium alginate content lengthened in vitro release time and in vivo t _max value. In addition, for ivivc, linear regression equations with r ² values of 0.8563 and 0.9402 were obtained for microparticles containing 1% and 2% (w/v) sodium alginate, respectively. Lower prediction error for 2% sodium alginate formulations (7.419 ± 4.068) compared to 1% sodium alginate formulations (9.458 ± 5.106) indicated a more precise ivivc for 2% sodium alginate formulation.     

Extraction and characterization of an alginate from the brown seaweed <Emphasis Type="Italic">Sargassum turbinarioides</Emphasis> Grunow

Matrix polysaccharide from the brown algae Sargassum turbinarioides collected in the coastal waters of Nosy Be (Madagascar) in the Indian Ocean was isolated and its structure was studied by ¹H-NMR spectroscopy, FT-IR, SEC-MALLS and HPAEC. An alginate with a molecular weight of 5.528 × 10⁵ g mol⁻¹ was identified as sole polysaccharide. Values of the M/G ratio, F _GG, F _MM and F _GM (or F _GM) blocks were measured at respectively 0.94, 0.39, 0.36 and 0.25 and compared with those of alginates from other Sargassum species. This sodium alginate appeared similar to some of the other Sargassum alginates with M/G < 1, high values of homopolymeric blocks (η < 1) and significant polyguluronic block content.     

Heterologous expression of polyhydroxyalkanoate depolymerase from <Emphasis Type="Italic">Thermobifida</Emphasis> sp. in <Emphasis Type="Italic">Pichia pastoris</Emphasis> and catalytic analysis by surface plasmon resonance

A polyhydroxyalkanote depolymerase gene from Thermobifida sp. isolate BCC23166 was cloned and expressed as a C-terminal His₆-tagged fusion in Pichia pastoris. Primary structure analysis revealed that the enzyme PhaZ-Th is a member of a proposed new subgroup of SCL-PHA depolymerase containing a proline–serine repeat linker. PhaZ-Th was expressed as two glycosylated forms with apparent molecular weights of 61 and 70 kDa, respectively. The enzyme showed esterase activity toward p-nitrophenyl alkanotes with V _max and K _m of 3.63 ± 0.16 μmol min⁻¹ mg⁻¹ and 0.79 ± 0.12 mM, respectively, on p-nitrophenyl butyrate with optimal activity at 50–55°C and pH 7–8. Surface plasmon resonance (SPR) analysis demonstrated that PhaZ-Th catalyzed the degradation of poly-[(R)-3-hydroxybutyrate] (PHB) films, which was accelerated in (R)-3-hydroxyvalerate copolymers with a maximum degradation rate of 882 ng cm⁻² h⁻¹ for poly[(R)-3-hydroxybutyrate-co-3-hydroxyvalerate] (12 mol% V). Surface deterioration, especially on the amorphous regions of PHB films was observed after exposure to PhaZ-Th by atomic force microscopy. The use of P. pastoris as an alternative recombinant system for bioplastic degrading enzymes in secreted form and a sensitive SPR analytical technique will be of utility for further study of bioplastic degradation.     

<Emphasis Type="Italic">In vitro</Emphasis> propagation of <Emphasis Type="Italic">Zingiber petiolatum</Emphasis> (Holttum)

Summary We describe an in vitro propagation protocol for Zingiber petiolatum (Holttum), I. Theilade, a rare species from the southern part of Thailand. Fruits were surface-sterilized and seeds germinated on Murashige and Skoog medium (MS) medium supplemented with 3% sucrose. Three-month-old seedlings were used as initial plant material for in vitro propagation. Terminal buds of the plants were inoculated on MS medium containing 6-benzylaminopurine (BA; 2.2–35.5 μM) alone or in combination with 1-naphthaleneacetic acid (0.5 μM). Eight weeks after inoculation, the cultures were transferred to MS medium without plant growth regulators for 4wk. The cultures transferred from MS medium with 17.8 μM BA revealed the highest shoot induction rate of 6.1±0.7 shoots per explant. Rooting was spontaneously achieved in MS medium without plant growth regulators. Rooted plants were successfully transplanted to soil.     

Optimization of protoplast yields from the red algae <Emphasis Type="Italic">Gracilaria dura</Emphasis> (C. Agardh) J. Agardh and G. <Emphasis Type="Italic">verrucosa</Emphasis> (Huds.) Papenfuss

This study reports on the optimization of protoplast yield from two important tropical agarophytes Gracilaria dura and Gracilaria verrucosa using different cell-wall-degrading enzymes obtained from commercial sources. The conditions for achieving the highest protoplast yield was investigated by optimizing key parameters such as enzyme combinations and their concentrations, duration of enzyme treatment, enzyme pH, mannitol concentration, and temperature. The significance of each key parameter was also further validated using the statistical central composite design. The enzyme composition with 4% cellulase Onozuka R-10, 2% macerozyme R-10, 0.5% pectolyase, and 100 U agarase, 0.4 M mannitol in seawater (30‰) adjusted to pH 7.5 produced the highest protoplast yields of 3.7 ± 0.7 × 10⁶ cells g⁻¹ fresh wt for G. dura and 1.2 ± 0.78 × 10⁶ cells g⁻¹ fresh wt for G. verrucosa when incubated at 25°C for 4–6 h duration. The young growing tips maximally released the protoplasts having a size of 7–15 μm in G. dura and 15–25 μm in G. verrucosa, mostly from epidermal and upper cortical regions. A few large-size protoplasts of 25–35 μm, presumably from cortical region, were also observed in G. verrucosa.     

Comparison of conditions for mycelial growth of <Emphasis Type="Italic">Lepista sordida</Emphasis> causing fairy rings on <Emphasis Type="Italic">Zoysia matrella</Emphasis> turf to those on <Emphasis Type="Italic">Agrostis palustris</Emphasis> turf

Symptoms of fairy rings caused by Lepista sordida have been reported on Zoysiagrass (Zoysia spp.) turf maintained at fairway height (2 cm), but not on bentgrass (Agrostis spp.) maintained at putting green height (0.5 cm). The mycelia of this fungus inhabit primarily the upper 0–2 cm layer of the soil extending into the thatch. To compare conditions for the mycelial growth in Z. matrella turf to those in A. palustris turf, we examined the effects of nutrients, temperature, water potential, and pH in the field as well as in the laboratory. Greater growth of the mycelia was observed in medium that included hot water extracts from soil of the 0–1 cm zone in Z. matrella turf compared to that from A. palustris. The upper soil layer in Z. matrella turf contained more organic matter from clippings than that in A. palustris. The temperature and water potential of the 0–2 cm soil zone in Z. matrella turf were also more favorable for the mycelial growth. The soil pH values of this zone in Z. matrella turf were less favorable compared to A. palustris but within the range for accelerating mycelial growth. Part of this study was presented orally at the 46th meeting of the Mycological Society of Japan in 2002     

Carrageenan of <Emphasis Type="Italic">Eucheuma isiforme</Emphasis> (Solieriaceae,Rhodophyta) from Nicaragua

The yield and physicochemical properties of native and alkali treated carrageenan from Eucheuma isiforme harvested from the Nicaraguan coast were investigated. The native carrageenan yield was 57.2% of dry weight and decreased to 43.5% when the alga was alkali treated. Native carrageenan viscosities showed significant differences between native (144.6 ± 3.3 cPs) and treated carrageenan (113.9 ± 2.6 cPs) (p < 0.01). Alkali treatment reduced carrageenan sulphate content by 19.3% and increased 3,6 AG content by 13%. Alkali-treated carrageenan formed very weak gels in 1.5% solutions (<50 g cm⁻²). Chemical analysis and FTIR spectra revealed that Eucheuma isiforme from Nicaragua is a good source of relatively pure iota-carrageenan with sufficient quality to serve as a substitute for traditional iota-carrageenan sources.     

Edible oil degradation by using yeast coculture of <Emphasis Type="Italic">Rhodotorula pacifica</Emphasis> ST3411 and <Emphasis Type="Italic">Cryptococcus laurentii</Emphasis> ST3412

To develop a microbial treatment of edible oil-contaminated wastewater, microorganisms capable of rapidly degrading edible oil were screened. The screening study yielded a yeast coculture comprising Rhodotorula pacifica strain ST3411 and Cryptococcus laurentii strain ST3412. The coculture was able to degrade efficiently even at low contents of nitrogen ([NH₄–N] = 240 mg/L) and phosphorus sources ([PO₄–P] = 90 mg/L). The 24-h degradation rate of 3,000 ppm mixed oils (salad oil/lard/beef tallow, 1:1 w/w) at 20°C was 39.8% ± 9.9% (means ± standard deviations of eight replicates). The highest degradation rate was observed at 20°C and pH 8. In a scaled-up experiment, the salad oil was rapidly degraded by the coculture from 671 ± 52.0 to 143 ± 96.7 ppm in 24 h, and the degradation rate was 79.4% ± 13.8% (means ± standard deviations of three replicates). In addition, a repetitive degradation was observed with the cell growth by only pH adjustment without addition of the cells.     

Growth of <Emphasis Type="Italic">Pseudomonas chloritidismutans</Emphasis> AW-1<Superscript>T</Superscript> on <Emphasis Type="Italic">n</Emphasis>-alkanes with chlorate as electron acceptor

Microbial (per)chlorate reduction is a unique process in which molecular oxygen is formed during the dismutation of chlorite. The oxygen thus formed may be used to degrade hydrocarbons by means of oxygenases under seemingly anoxic conditions. Up to now, no bacterium has been described that grows on aliphatic hydrocarbons with chlorate. Here, we report that Pseudomonas chloritidismutans AW-1^T grows on n-alkanes (ranging from C7 until C12) with chlorate as electron acceptor. Strain AW-1^T also grows on the intermediates of the presumed n-alkane degradation pathway. The specific growth rates on n-decane and chlorate and n-decane and oxygen were 0.5 ± 0.1 and 0.4 ± 0.02 day⁻¹, respectively. The key enzymes chlorate reductase and chlorite dismutase were assayed and found to be present. The oxygen-dependent alkane oxidation was demonstrated in whole-cell suspensions. The strain degrades n-alkanes with oxygen and chlorate but not with nitrate, thus suggesting that the strain employs oxygenase-dependent pathways for the breakdown of n-alkanes.     

Biotechnological production of <Emphasis Type="SmallCaps">l</Emphasis>-ribose from <Emphasis Type="SmallCaps">l</Emphasis>-arabinose

l-Ribose is a rare and expensive sugar that can be used as a precursor for the production of l-nucleoside analogues, which are used as antiviral drugs. In this work, we describe a novel way of producing l-ribose from the readily available raw material l-arabinose. This was achieved by introducing l-ribose isomerase activity into l-ribulokinase-deficient Escherichia coli UP1110 and Lactobacillus plantarum BPT197 strains. The process for l-ribose production by resting cells was investigated. The initial l-ribose production rates at 39°C and pH 8 were 0.46 ± 0.01 g g⁻¹ h⁻¹ (1.84 ± 0.03 g l⁻¹ h⁻¹) and 0.27 ± 0.01 g g⁻¹ h⁻¹ (1.91 ± 0.1 g l⁻¹ h⁻¹) for E. coli and for L. plantarum, respectively. Conversions were around 20% at their highest in the experiments. Also partially purified protein precipitates having both l-arabinose isomerase and l-ribose isomerase activity were successfully used for converting l-arabinose to l-ribose.     

Evidence of <Emphasis Type="Italic">Anaplasma phagocytophilum</Emphasis> and <Emphasis Type="Italic">Rickettsia helvetica</Emphasis> infection in free-ranging ungulates in central Slovakia

The purpose of this study was to investigate the role of wild animals for Anaplasma phagocytophilum, other ehrlichiae/anaplasmae, Rickettsia helvetica and other rickettsiae and whether different genetic variants of A. phagocytophilum in central Slovakia exist. A total of 109 spleen samples from 49 red deer (Cervus elaphus), 30 roe deer (Capreolus capreolus), 28 wild boar (Sus scrofa) and two mouflon (Ovis musimon) were collected from June 2005 to December 2006. Polymerase chain reaction (PCR) amplification of the16S rRNA gene was used for detection of ehrlichiae/anaplasmae. A nested PCR targeting part (392 bp) of groESL gene was applied for the specific detection of A. phagocytophilum. Fragments of the gltA and ompA genes (381 bp and 632 bp, respectively) were amplified to detect rickettsiae, followed by sequencing. A. phagocytophilum and R. helvetica were detected in wild animals. The prevalence of A. phagocytophilum was 50.0 ± 18.2% in roe deer and 53.1 ± 14.1% in red deer. None of the 28 wild boar was PCR positive for ehrlichiae/anaplasmae. A. phagocytophilum was detected in one mouflon. R. helvetica was found in one roe deer. Our study suggests a role of cervids as a natural reservoir of A. phagocytophilum in Slovakia. However, the role of cervids and wild boars in the circulation of R. helvetica remains unknown. The analysis of sequence variation in the msp4 coding region of A. phagocytophilum showed the presence of different variants previously described in ruminants.     

<Emphasis Type="Italic">In vitro</Emphasis> propagation of <Emphasis Type="Italic">Decalepis arayalpathra</Emphasis>, a critically endangered ethnomedicinal plant

Summary This study reports a protocol for successful micropropagation of Decalepis arayalpathra (Joseph and Chandras) Venter. (Janakia arayalpathra Joseph and Chandrasekhran; Periplocaceae), a critically endangered and endemic ethnomedicinal plant in the southern forests of the Western Ghats which is overexploited for its tuberous medicinal roots by the local Kani tribes. Natural regeneration is rare and conventional propagation is difficult. Conservation of the species through micropropagation was attempted. The nodal explants of greenhouse-raised plants, were more desirable than cotyledonary nodal explants of aseptic seedlings. The basal nodes (73%) of 12–16-wk-old greenhouse-grown plants cultured in Murashige and Skoog (MS) medium containing 12.96 μM 6-benzyladenine (BA), 2.48 μM 2-isopentenyladenine (2-ip) and 2.68 μM α-naphthaleneacetic acid (NAA) formed 16–17 cm long unbranched robust solitary shoots in 8 wk. Cotyledonary nodal explants cultured in the same medium showed multiple shoot formation and axillary branching. But the shoots were thin, fragile and not suitable for mass propagation. Single nodes of a solitary shoot subcultured on MS medium containing 2.22 μM BA and 0.24 μM 2-ip together produced 9.8±0.3 nodes from 18.0±0.6 cm long shoots within 5–6 wk. The basal nodes of the shoots so formed were repeatedly subcultured to increase the stock of propagules while the 2.5–3.0 cm terminal cuttings were used for rooting. The best root induction (68%) and survival (86%) was achieved on half-strength MS medium supplemented with 1.07 μM NAA. Field-established plants showed uniform growth and phenotypic similarity to parental stock.     

Eggs and larvae of <Emphasis Type="Italic">Awaous melanocephalus</Emphasis> (Teleostei: Gobiidae)

The morphology of eggs and larvae of Awaous melanocephalus is described. The eggs measured 0.33–0.35 mm in long-axis diameter and 0.32–0.34 mm in short-axis diameter. Newly hatched larvae (0.90–0.99 mm in notochord length, NL; 0.93–1.04 mm in total length, TL) were poorly developed, lacking a mouth and having a large yolk sac and unpigmented eyes. The mouth opened and the eyes became fully pigmented 3 days after hatching (1.78–2.00 mm NL, 1.88–2.10 mm TL). The yolk sac was completely absorbed 5 days after hatching at a water temperature of 27°–28°C.     

Antibacterial Activities of Novel Diselenide-bridged <Emphasis Type="Italic">bis</Emphasis>(Porphyrin)s on <Emphasis Type="Italic">Staphylococcus aureus</Emphasis> Investigated by Microcalorimetry

The actions of two novel diselenide-bridged bis(porphyrin)s (1 and 2) on Staphylococcus aureus growth was investigated by microcalorimetry at 37.00°C, compared with that of Na₂SeO₃. Differences in their capacities to inhibit the growth metabolism of S. aureus were observed. By analyzing the power–time curves, crucial parameters such as the rate constant of bacterial growth (k), inhibitory rate (I), and generation time (t _G) were determined. The growth rate constant (k) of S. aureus (in the log phase) in the presence of the drugs decreased with increasing concentrations of the drugs regularly. The relationship of k and c is nearly linear for diselenide-bridged bis(porphyrin) 2. The sequence of the antibacterial activities of these selenium compounds tested was 2 > 1 > Na₂SeO₃.     

<Emphasis Type="Italic">Organogenic callus</Emphasis> as the target for plant regeneration and transformation via <Emphasis Type="Italic">Agrobacterium</Emphasis> in soybean (<Emphasis Type="Italic">Glycine max</Emphasis> (L.) Merr.)

A regeneration and transformation system has been developed using organogenic calluses derived from soybean axillary nodes as the starting explants. Leaf-node or cotyledonary-node explants were prepared from 7 to 8-d-old seedlings. Callus was induced on medium containing either Murashige and Skoog (MS) salts or modified Finer and Nagasawa (FNL) salts and B5 vitamins with various concentrations of benzylamino purine (BA) and thidiazuron (TDZ). The combination of BA and TDZ had a synergistic effect on callus induction. Shoot differentiation from the callus occurred once the callus was transferred to medium containing a low concentration of BA. Subsequently, shoots were elongated on medium containing indole-3-acetic acid (IAA), zeatin riboside, and gibberellic acid (GA). Plant regeneration from callus occurred 90 ∼ 120 d after the callus was cultured on shoot induction medium. Both the primary callus and the proliferated callus were used as explants for Agrobacterium-mediated transformation. The calluses were inoculated with A. tumefaciens harboring a binary vector with the bar gene as the selectable marker gene and the gusINT gene for GUS expression. Usually 60–100% of the callus showed transient GUS expression 5 d after inoculation. Infected calluses were then selected on media amended with various concentrations of glufosinate. Transgenic soybean plants have been regenerated and established in the greenhouse. GUS expression was exhibited in various tissues and plant organs, including leaf, stem, and roots. Southern and T₁ plant segregation analysis of transgenic events showed that transgenes were integrated into the soybean genome with a copy number ranging from 1–5 copies.     

Antioxidant Properties of Selected <Emphasis Type="Italic">Boletus</Emphasis> Mushrooms

Considering the growing interest for mushrooms and the demand search of natural antioxidants sources, the aim of this study was to investigate the antioxidant properties of two edible widely used Boletus species, Boletus edulis, and Boletus auranticus, collected from Istra region in Croatia in late summer 2007. To evaluate the antioxidant properties and content of antioxidant compounds, scavenging capacity on DPPH˙, OH˙, and O₂˙⁻ radicals, reducing power and capacity to inhibit lipid peroxidation has been investigated. It is determined that content of total phenols (41.82 ± 0.08 mg gallic acid equivalent per gram of dry extract) was higher for B. edulis. Using high performance liquid chromatography/diode array detector analysis, the main antioxidant compound, variegatic acid, has been detected and quantified. 1,1-Diphenyl-2-picryl-hydrazyl-hydrate assay was used as a preliminary free radical–scavenging evaluation. By this assay, it has been found that B. edulis dry mushroom extract exhibits 50% of inhibition value at the extract concentration of 0.016 ± 0.0003 mg/ml. The extracts were capable of reducing iron(III) and, thus, are capable of donating electrons. Using electron paramagnetic resonance spin-trapping and spin-probing techniques, activity against relevant reactive species, ˙OH and O₂˙⁻ radical, was analyzed for both mushroom extracts. Both investigated extracts are determined as good inhibitors for ˙OH radical reduction, and both exhibited significant capacity for scavenging O₂˙⁻ radical and for that could help to prevent or meliorate oxidative damage. Only B. edulis extract prevents lipid peroxidation. Investigated mushroom extracts could represent easily accessible natural antioxidant resource.