Suillus Bellinii Research Articles

Wild mushrooms and their mycelia as sources of bioactive compounds: Antioxidant, anti-inflammatory and cytotoxic properties.

Mushrooms are important sources of natural bioactive compounds. Pleurotus eryngii (DC.) Quél is recognized for its organoleptic quality and health effects, being extensively commercialized. Instead, Suillus bellinii (Inzenga) Watling is an ectomycorrhizal symbiont, whose main properties were scarcely reported. Considering current trends, the mycelia and the culture media of these mushrooms might be potential sources of bioactive compounds. Accordingly, P. eryngii and S. bellinii were studied for their phenolic acids and sterols, antioxidant capacity, anti-inflammatory effect and anti-proliferative activity. S. bellinii mycelia showed higher contents of ergosterol and phenolic compounds (also higher in its fruiting body) and stronger antioxidant activity than P. eryngii. Conversely, P. eryngii mycelia showed anti-inflammatory (absent in S. bellinii mycelia) and a cytotoxicity similar (sometimes superior) to its fruiting bodies, contrarily to S. bellinii. Furthermore, the assayed species showed differences in the growth rate and produced mycelia, which should be considered in further applications.

Primary and secondary metabolites of an European edible mushroom and its nutraceutical value: Suillus bellinii (Inzenga) Kuntze

In this work, we report the study on the composition in primary and secondary metabolites of the polar and less-polar fractions obtained from the fruiting bodies of Suillus bellinii (Inzenga) Kuntze collected from Central Italy. Thirteen compounds were identified through a series of classical chromatographic methods and through spectroscopic techniques (nuclear magnetic resonance (NMR) and mass spectrometry (MS)), namely suillin (1), ergosterol (2), glutamic acid (3), isoleucine (4), leucine (5), threonine (6), tyrosine (7), valine (8), D-mannitol (9), sucrose (10), D-sorbitol (11), fumaric acid (12) and alanine (13). These results allowed us to make specific considerations about the possible applications of this mushroom, which vary from medicine, due to the high cytotoxic and antitumor properties of suillin (1), to nutritional values, due to the presence of essential nutrients as amino acids and pre-vitamin D2 (ergosterol), together with low-calories sweeteners, confirming the close association between the identified components and the health-promoting properties of this species.

Effect of benfluralin on Pinus pinea seedlings mycorrhized with Pisolithus tinctorius and Suillus bellinii – Study of plant antioxidant response

In this study, Pinus pinea seedlings mycorrhized with selected ectomycorrhizal fungi (ECMF), Pisolithus tinctorius and Suillus bellinii, were exposed to the herbicide benfluralin. Non-mycorrhized P. pinea seedlings and seedlings mycorrhized with ECMF were transferred to benfluralin-spiked soils at levels of 0.165, 1.65 and 16.5mgkg−1. Plant growth and the fungal role on plant antioxidant response were assessed. In the presence of benfluralin, higher plant growth was observed in mycorrhized plants compared to non-mycorrhized plants, but ECMF colonisation and nutrient uptake were affected by the herbicide. Benfluralin showed no effect on lipid peroxidation in P. pinea seedlings. However, seedlings mycorrhized with S. bellinii showed higher levels of lipid peroxidation when compared to non-mycorrhized ones, both in the presence and absence of benfluralin. The increase of lipid peroxidation could be related to seedling growth induced by the fungus and not to benfluralin toxicity. A similar trend was observed in seedlings mycorrhized with P. tinctorius when exposed to higher benfluralin concentrations, suggesting that the antioxidant response to benfluralin is related not only to fungus species, but also to the level of stress applied in the soil. The higher amount of superoxide dismutase activity in P. pinea seedlings tissues exposed to benfluralin could indicate a plant adaptative response to benfluralin toxicity. Catalase activity showed no increase with benfluralin exposure. Pre-established P. tinctorius mycorrhization conferred root protection and enhanced plant growth in benfluralin spiked soil, inferring that P. tinctorius – P. pinea association could advantageous for plant growth in soils contaminated with pesticides.

Inoculation of Pinus pinea seedlings with Pisolithus tinctorius and Suillus bellinii promotes plant growth in benfluralin contaminated soil

In order to develop new strategies aiming at reconverting agriculture-managed soils into forest plantations, pesticides effect on plant growth needs to be further understood. Thus, the development of Pinus pinea seedlings on soil spiked with benfluralin mimicking different application rates was evaluated, as a well as its effect on root colonisation with Pisolithus tinctorius and Suillus bellinii. P. pinea development and ectomycorrhiza colonization on soil spiked with benfluralin were assessed after 6 month growth. P. pinea seedlings inoculated with P. tinctorius showed higher plant growth and increased nutrient levels than seedlings inoculated with S. bellinii. At field application rate, benfluralin had an inhibitory effect on growth of non inoculated plants. Inoculation with P. tinctorius promoted plant development and nutrient uptake whereas inoculation with S. bellinii did not seem to confer plant protection against the toxic. Although P. tinctorius and S. bellinii were able to form ectomycorrhizae in the presence of benfluralin, the extent of root colonisation was affected by the herbicide. P. tinctorius conferred protection to P. pinea against benfluralin toxicity, overcoming the effect of the herbicide on P. pinea growth and nutrient uptake. This approach can be advantageous for plant establishment on pesticide contaminated soils.

Bioactive microconstituents and antioxidant properties of wild edible mushrooms from the island of Lesvos, Greece

Crude composition, fatty acids, sterols, total phenolic content (TPC), individual polyphenols and terpenic acids were determined in five wild edible mushrooms species (Lactarius deliciosus, Lactarius sanguifluus, Lactarius semisanguifluus, Russula delica, Suillus bellinii) from Lesvos Island, Greece. In addition, the DPPH scavenging capacity, the ferric ion reducing power (FRAP) and the ferrous ion chelating activity of mushroom methanolic extracts were assessed. Among sterols, ergosterol predominated at concentrations 9.2-18.0mg/100g fw. Total phenolic content of mushroom extracts ranged from 6.0 to 20.8mg GAE/100g fw. Up to 19 simple polyphenols were determined in mushrooms extracts, the more abundant being p-OH-benzoic acid, p-OH-phenylacetic acid, o-coumaric acid, ferulic acid and chrysin. In addition, the triterpenic acids oleanolic and ursolic were detected for the first time in mushrooms. All species exerted antioxidant activity and ferrous ion chelating capacity. Principal component analysis revealed good correlations between TPC, DPPH and FRAP but not with metal chelating activity. It seems that mushrooms polyphenols exert antiradical and reducing activities, but they are not strong metal chelators, the observed chelating ability being probably due to other classes of compounds. To our knowledge, this is the first report on the bioactive microconstituents and antioxidant activity of wild Greek edible mushrooms.

Trace metal contents in wild edible mushrooms growing on serpentine and volcanic soils on the island of Lesvos, Greece

The objectives of this survey were (1) to assess for the first time the Cd, Cu, Cr, Fe, Mn, Ni, Pb and Zn contents in wild edible mushrooms (Russula delica, Lactarius sanguifluus, Lactarius semisanguifluus, Lactarius deliciosus, Suillus bellinii) from the island of Lesvos, (2) to investigate the metals' variability among the species, as well as in relation to the chemical composition of the underlying soil, comparing mushrooms collected from volcanic and serpentine substrates and (3) to estimate metal intake by the consumption of the mushrooms under consideration. The trace metals in 139 samples were determined by flame or flameless atomic absorption spectroscopy. The median metal concentrations were as follows: Cd: 0.14; Cr: 0.10; Cu: 8.51; Fe: 30.3; Mn: 5.26; Ni: 0.34; Pb: 0.093 and Zn: 64.50, all in mgkg−1 dry weight. The observed concentrations are among the lowest reported for mushrooms from Europe or Turkey, while Pb and Cd values did not exceed the limits set by the European Union. Significant species- and substrate-related differences in the metal contents were found, but the variability did not follow a uniform pattern for all the metals in all mushroom species. As a general trend, the mushrooms growing in serpentine sites contained higher Cd, Cr and Ni than those from volcanic sites. The calculated bioconcentration factors (BCFs) showed that none of the mushrooms can be regarded as a metal bioaccumulator, although BCF values slightly above unity were found for Zn in the three Lactarius species, and for Cu in R. delica.The studied mushrooms could supply considerable amounts of essential metals such as Zn and Cr. On the other hand, the consumption of R. delica collected from volcanic soils could provide 12% of the Cd daily tolerable intake and as high as 53% when collected from serpentine soils. Nonetheless, our results indicate that the regular consumption of wild edible mushrooms from Lesvos is quite safe for human health.

Fatty acid composition of wild edible mushrooms species: A comparative study

A comparative study was developed on the total fatty acids composition of twelve wild edible mushroom species ( Suillus bellini, Suillus luteus, Suillus granulatus, Hygrophorus agathosmus, Amanita rubescens, Russula cyanoxantha, Boletus edulis, Tricholoma equestre, Fistulina hepatica, Cantharellus cibarius, Amanita caesarea and Hydnum rufescens). In order to define qualitative and quantitative profiles, combined fatty acids were hydrolyzed with potassium hydroxide/methanol and all free compounds were derived to their methyl ester forms with methanolic boron trifluoride, followed by analysis by GC-MS. Thirty fatty acids were determined. As far as we know, the fatty acid profiles of A. caesarea and H. rufescens are described for the first time. As for the remaining species, a high number of new compounds were identified, which much improved the knowledge about their fatty acids profiles. In general, oleic, linoleic, palmitic and stearic acids were present in highest contents. Polyunsaturated and monounsaturated fatty acids, valuable healthy compounds for humans, predominated over saturated fatty acids for all the studied mushroom species. R. cyanoxantha presented the highest fatty acids amounts, while B. edulis was the poorest species. By Agglomerative Hierarchic Cluster Analysis the studied species were gathered in 5 groups, based in their fatty acid patterns.

Comparative Study on Free Amino Acid Composition of Wild Edible Mushroom Species

A comparative study on the amino acid composition of 11 wild edible mushroom species (Suillus bellini, Suillus luteus, Suillus granulatus, Tricholomopsis rutilans, Hygrophorus agathosmus, Amanita rubescens, Russula cyanoxantha, Boletus edulis, Tricholoma equestre, Fistulina hepatica, and Cantharellus cibarius) was developed. To define the qualitative and quantitative profiles, a derivatization procedure with dabsyl chloride was performed, followed by HPLC-UV-vis analysis. Twenty free amino acids (aspartic acid, glutamic acid, asparagine, glutamine, serine, threonine, glycine, alanine, valine, proline, arginine, isoleucine, leucine, tryptophan, phenylalanine, cysteine, ornithine, lysine, histidine, and tyrosine) were determined. B. edulis and T. equestre were revealed to be the most nutritional species, whereas F. hepatica was the poorest. The different species exhibited distinct free amino acid profiles. The quantification of the identified compounds indicated that, in a general way, alanine was the major amino acid. The results show that the analyzed mushroom species possess moderate amino acid contents, which may be relevant from a nutritional point of view because these compounds are indispensable for human health. A combination of different mushroom species in the diet would offer good amounts of amino acids and a great diversity of palatable sensations.

Correlation between the Pattern Volatiles and the Overall Aroma of Wild Edible Mushrooms

Volatile and semivolatile components of 11 wild edible mushrooms, Suillus bellini, Suillus luteus, Suillus granulatus, Tricholomopsis rutilans, Hygrophorus agathosmus, Amanita rubescens, Russula cyanoxantha, Boletus edulis, Tricholoma equestre, Fistulina hepatica, and Cantharellus cibarius, were determined by headspace solid-phase microextraction (HS-SPME) and by liquid extraction combined with gas chromatography-mass spectrometry (GC-MS). Fifty volatiles and nonvolatiles components were formally identified and 13 others were tentatively identified. Using sensorial analysis, the descriptors "mushroomlike", "farm-feed", "floral", "honeylike", "hay-herb", and "nutty" were obtained. A correlation between sensory descriptors and volatiles was observed by applying multivariate analysis (principal component analysis and agglomerative hierarchic cluster analysis) to the sensorial and chemical data. The studied edible mushrooms can be divided in three groups. One of them is rich in C8 derivatives, such as 3-octanol, 1-octen-3-ol, trans-2-octen-1-ol, 3-octanone, and 1-octen-3-one; another one is rich in terpenic volatile compounds; and the last one is rich in methional. The presence and contents of these compounds give a considerable contribution to the sensory characteristics of the analyzed species.

Contents of Carboxylic Acids and Two Phenolics and Antioxidant Activity of Dried Portuguese Wild Edible Mushrooms

The organic acids and phenolics compositions of nine wild edible mushrooms species (Suillus bellini, Tricholomopsis rutilans, Hygrophorus agathosmus, Amanita rubescens, Russula cyanoxantha, Boletus edulis, Tricholoma equestre, Suillus luteus, and Suillus granulatus) were determined by HPLC-UV and HPLC-DAD, respectively. The antioxidant potential of these species was also assessed by using the DPPH* scavenging assay. The results showed that all of the species presented a profile composed of at least five organic acids: oxalic, citric, malic, quinic, and fumaric acids. In a general way, the pair of malic plus quinic acids were the major compounds. Only very small amounts of two phenolic compounds were found in some of the analyzed species: p-hydroxybenzoic acid (in A. rubescens, R. cyanoxantha, and T. equestre) and quercetin (in S. luteus and S. granulatus). All of the species exhibited a concentration-dependent scavenging ability against DPPH*. T. rutilans revealed the highest antioxidant capacity.

Molecular characterization and evaluation of mycorrhizal capacity of Suillus isolates from Central Spain for the selection of fungal inoculants

Suillus fungal specimens of pine forests from a Mediterranean area of central Spain (Madrid region) were studied based on molecular and physiological analysis of sporocarps to obtain fungal native inocula to produce mycorrhizal Pinus halepensis Miller in nursery. Variation within the internal transcribed spacer (ITS) region of the ribosomal RNA genes of Suillus was examined by restriction fragment length polymorphism (RFLP) and direct sequencing of polymerase chain reaction products. Ribosomal DNA (rDNA) spacers were amplified from pure cultures obtained from fruit bodies of a range of Suillus species: Suillus bellinii (Inzenga) Watling, Suillus bovinus (Pers.) Kuntze, Suillus collinitus (Fr.) Kuntze, Suillus granulatus (L.) Snell, Suillus mediterraneensis (Jacquet. & Blum) Redeuil, Suillus luteus L. (Gray), and Suillus variegatus (Sw.) Kuntze. Interspecific variation in the length and number of restriction sites of the amplified ITS region was observed. This variation was confirmed by sequencing, which allowed us to identify some isolates. This is the first time that the ITS sequence of S. mediterraneensis is completely described. No intraspecific rDNA variation was observed within isolates of S. collinitus, S. mediterraneensis, and S. luteus. The phylogenetic analysis established the close relationship among these Mediterranean fungal species. As a further step to characterize the different isolates and to understand the relation between genetic and functional diversity, some physiological variables were evaluated. Intraspecific variation in axenic fungal growth and in mycorrhizal capacities was detected, especially within S. collinitus isolates. The fungal isolates stimulated the growth of P. halepensis in different rates. These studies indicated that ITS analysis, in conjunction with mycorrhizal tests, provides suitable combined tools for the analysis of Suillus spp. in a small geographic area for selecting isolates with final afforestation purposes.

Comparaison des activités phosphatases ?Homobasidiomycètes ectomycorhiziens en culture in vitro

AbstractComparison of phosphatase activities in ectomycorrhizal Homobasidiomycetes cultured in vitro. Phosphatase activities, measured on intact mycelia (accessible activities) or on mycelial homogenates (total activities), were compared in twelve ectomy corrhizal strains of Homobasidiomycetes (Hebeloma cylindrosporum, Laccaria laccata; Suillus bellini; S. bovinus; S. granulatus; S. luteus, Pisolithus arhizus). The effects of the following factors were examined: (i) two orthophosphate concentrations in the culture medium; (ii) two incubation substrates (sodium p‐nitrophenylphosphate or sodium phytate). Phosphatase activities were highest when mycelial homogenates were incubated in the presence of p‐nitrophenyl phosphate after culturing the mycelia on medium slightly deficient in orthophosphate, particularly in the case of one S. granulatus isolate.

Protoplast production and regeneration from mycorrhizal fungi and their use for isolation of mutants

Methods were developed for the reproducible production of high yields of stable protoplasts from monokaryotic and dikaryotic mycelia of Hebeloma cylindrosporum. This is a prerequisite for mutation, cell fusion, and transformation of this mycorrhizal fungus. Protoplasts from Hebeloma cylindrosporum, Hebeloma edurum, Hebeloma sinapizans, and Suillus bellini were released by using cellulase Onozuka R 10 and driselase as lytic enzymes. Production was strongly influenced by the nature and molarity of the osmotic stabilizer and by the mycelial age. In spite of the high percentage of anucleate protoplasts (42%) produced, the regeneration rate averaged 15%. Fungicide-resistant mutants from monokaryotic mycelia of H. cylindrosporum were isolated following ultraviolet irradiation of protoplasts. This indicates that protoplasts will be useful to select physiological mutants from nonsporulating mycelia and to create new strains by mating complementary mycelia or by interspecific cell fusion.