我国牛肝菌属一新种,微眇牛肝菌

在福建省新发现一担子果极小的微眇牛肝菌,其盖径仅1-4mm,柄高3-6mm,极罕见,暂归于牛肝菌属黄肉牛肝菌组。     

Evaluation of Mercury Contamination in Fungi Boletus Species from Latosols,Lateritic Red Earths,and Red and Yellow Earths in the Circum-Pacific Mercuriferous Belt of Southwestern China

For the first time, highly elevated levels of mercury (Hg) have been documented for several species of the edible Fungi genus Boletus growing in latosols, lateritic red earths, and red and yellow earths from the Yunnan province of China. Analysis of Hg concentrations in the genus suggests that geogenic Hg is the dominant source of Hg in the fungi, whereas anthropogenic sources accumulate largely in the organic layer of the forest soil horizon. Among the 21 species studied from 32 locations across Yunnan and 2 places in Sichuan Province, the Hg was found at elevated level in all samples from Yunnan but not in the samples from Sichuan, which is located outside the mercuriferous belt. Particularly abundant in Hg were the caps of fruiting bodies of Boletus aereus (up to 13 mg kg^-1 dry matter), Boletus bicolor (up to 5.5 mg kg^-1 dry matter), Boletus edulis (up to 22 mg kg^-1 dry matter), Boletus luridus (up to 11 mg kg^-1 dry matter), Boletus magnificus (up to 13 mg kg^-1 dry matter), Boletus obscureumbrinus (up to 9.4 mg kg^-1 dry matter), Boletus purpureus (up to 16 mg kg^-1 dry matter), Boletus sinicus (up to 6.8 mg kg^-1 dry matter), Boletus speciosus (up to 4.9mg kg^-1 dry matter), Boletus tomentipes (up to 13 mg kg^-1 dry matter), and Boletus umbriniporus (up to 4.9 mg kg^-1 dry matter). Soil samples of the 0–10 cm topsoil layer from the widely distributed locations had mercury levels ranging between 0.034 to 3.4 mg kg^-1 dry matter. In Yunnan, both the soil parent rock and fruiting bodies of Boletus spp. were enriched in Hg, whereas the same species from Sichuan, located outside the mercuriferous belt, had low Hg concentrations, suggesting that the Hg in the Yunnan samples is mainly from geogenic sources rather than anthropogenic sources. However, the contribution of anthropogenically-derived Hg sequestered within soils of Yunnan has not been quantified, so more future research is required. Our results suggest that high rates of consumption of Boletus spp. from Yunnan can deliver relatively high doses of Hg to consumers, but that rates can differ widely because of large variability in mercury concentrations between species and locations.     

Sutorius: a new genus for Boletus eximius

Sutorius is described as a new genus of Boletaceae to accommodate Boletus robustus originally named illegitimately by C.C. Frost from eastern North America. The legitimate name, Boletus eximius, provided by C.H. Peck, has been used since for a dark purple to chocolate brown bolete with finely scaly stipe and reddish brown spore deposit. This iconic taxon has been documented on five continents. Despite the straightforward species identification from morphology, the interpretation of stipe macro-morphology and spore color has led to equivocal generic placement. Phylogenetic analyses of genes encoding large subunit rRNA and translation elongation factor 1α confirm Sutorius as a unique generic lineage in the Boletaceae. Two species are recognized based on multiple accessions: S. eximius, represented by collections from North America, Costa Rica, Guyana, Indonesia and Japan (molecular data are lacking for only the Guyanan and Japanese material); and S. australiensis, represented by material from Queensland, Australia. Additional collections from Zambia and Thailand represent independent lineages, but sampling is insufficient to describe new species for these entities.     

ITS primers for the identification of marketable Boletus

Boletus species belonging to the section Boletus are the most frequently eaten fungi among those harvested in natural conditions in Europe. This section groups 10 taxa which are hardly distinguishable on the basis of their morphology. Some of them have been shown to induce allergic IgE-mediated symptoms either through inhalation, ingestion or contact. Since questions relating to the presence of allergens in any of the species most in demand (B. edulis, B. aereus, B. pinophilus, B. aestivalis, all classified as B. edulis s.l.) remain open, together with the absence of tools which distinguish the species, we sequenced the ITS region of 28 Boletus samples and then we designed specific primers. These allowed the effective separation of the taxa. In addition, the phylogenetic tree obtained from the sequences alignment revealed that B. violaceofuscus, a spectacular Chinese fungus considered belonging to the section Boletus and often sold intermixed with B. edulis s.l. specimens, clusters outside the section Boletus.     

Structure elucidation and antioxidant activity of a novel polysaccharide isolated from Boletus speciosus Forst

In this study, a novel heteropolysaccharide was isolated from the fruiting bodies of Boletus speciosus Forst through DEAE-cellulose column and Sephadex G-200 column. The Boletus speciosus Forst polysaccharide (BSFP-1) had a molecular weight of 1.33×10(4) Da and was mainly composed of l-Man and d-Gal which ratios were 2:1. Structural features of Boletus speciosus Forst polysaccharide (BSFP-1) were investigated by a combination of total hydrolysis, methylation analysis, gas chromatography-mass spectrometry (GC-MS), infrared (IR) spectra and nuclear magnetic resonance (NMR) spectroscopy. The results indicated that Boletus speciosus Forst polysaccharide (BSFP-1) had a backbone of (1→4)-α-l-mannopyranose residues which branches at O-6 based on the experimental results. The branches were mainly composed of one with →1)-α-d-galactopyranose residue. The antioxidant activity of BSFP-1 was evaluated with two biochemical methods, including 1,1-diphenyl-2-picrylhydrazyl (DPPH(-)) radical scavenging, scavenging activity of 2,2'-azino-bis(3-ethylbenzthiazoline-6-suphonic acid)diammonium (ABTS(+)) radical. The results indicated that BSFP-1 showed strong antioxidant.     

Boletus roseoflavus,a new species of Boletus in section Appendiculati from China

Boletus roseoflavus is described as a new species based on morphological and molecular studies of the type collection and additional materials. Boletus roseoflavus is morphologically distinct from other related species (B. regius, B. appendiculatus, and B. speciosus) by its light pink, pink, or rosy pileus, lemon yellow or golden yellow context, and lemon yellow or light yellow, enlarged download stipe with yellow reticulation. Phylogenetic analyses based on ribosomal DNA internal transcribed spacer regions and nuclear large subunit ribosomal RNA indicate that B. roseoflavus belongs to Boletus section Appendiculati.     

Molecular phylogenetics of porcini mushrooms (Boletus section Boletus)

Porcini (Boletus section Boletus: Boletaceae: Boletineae: Boletales) are a conspicuous group of wild, edible mushrooms characterized by fleshy fruiting bodies with a poroid hymenophore that is "stuffed" with white hyphae when young. Their reported distribution is with ectomycorrhizal plants throughout the Northern Hemisphere. Little progress has been made on the systematics of this group using modern molecular phylogenetic tools because sampling has been limited primarily to European species and the genes employed were insufficient to resolve the phylogeny. We examined the evolutionary history of porcini by using a global geographic sampling of most known species, new discoveries from little explored areas, and multiple genes. We used 78 sequences from the fast-evolving nuclear internal transcribed spacers and are able to recognize 18 reciprocally monophyletic species. To address whether or not porcini form a monophyletic group, we compiled a broadly sampled dataset of 41 taxa, including other members of the Boletineae, and used separate and combined phylogenetic analysis of sequences from the nuclear large subunit ribosomal DNA, the largest subunit of RNA polymerase II, and the mitochondrial ATPase subunit six gene. Contrary to previous studies, our separate and combined phylogenetic analyses support the monophyly of porcini. We also report the discovery of two taxa that expand the known distribution of porcini to Australia and Thailand and have ancient phylogenetic connections to the rest of the group. A relaxed molecular clock analysis with these new taxa dates the origin of porcini to between 42 and 54 million years ago, coinciding with the initial diversification of angiosperms, during the Eocene epoch when the climate was warm and humid. These results reveal an unexpected diversity, distribution, and ancient origin of a group of commercially valuable mushrooms that may provide an economic incentive for conservation and support the hypothesis of a tropical origin of the ectomycorrhizal symbiosis.     

Boletus mendax,a new species of Boletus sect. Luridi from Italy and insights on the B. luridus complex

The new species Boletus mendax of sect. Luridi is reported and discussed; its morphological, anatomical and edaphic characters are described and a molecular investigation is carried out in order to elucidate the separation from neighboring taxa. The present research also demonstrates the high degree of segregation of two collections of the recently described Boletus comptus and the low taxonomic value of the usual reddish pigmentation of the subhymenophoral layer (the so called Bataille’s line) for both taxa B. mendax and B. luridus. Colour pictures taken in habitat of the taxa presented herein are also provided. Finally, according to an ITS analysis, sect. Luridi is shown to be polyphyletic and the importance of morphological features as stipe ornamentation, context colour beneath tubes and amyloid reaction in stipe base is discussed.     

A new species of Boletus section Luridi from Colombia

Boletus pyrrhosceles (sectionLuridi) is newly described from Dept. Nariño, where it is associated withQuercus humboldtii. This is the first report of a red-pored bolete from Colombia.     

Bolevenine, a toxic protein from the Japanese toadstool Boletus venenatus

A toxic protein, called bolevenine, was isolated from the toxic mushroom Boletus venenatus based on its lethal effects on mice. On SDS-PAGE, in either the presence or absence of 2-mercaptoethanol, this protein showed a single band of approximately 12 kDa. In contrast, based on gel filtration and MALDI-TOFMS, its relative molecular mass was estimated to be approximately 30 kDa and approximately 33 kDa, respectively, indicating that the protein consists of three identical subunits. This toxin exhibited its lethal activity following injection at 10mg/kg into mice. The N-terminal amino acid sequence was determined up to 18, and found to be similar to the previously reported bolesatine, a toxic compound isolated from Boletus satanas.     

美味牛肝菌多糖最佳提取工艺研究

对美味牛肝菌 (BoletusedulisBull)子实体多糖提取最佳工艺条件进行了研究。通过实验既探讨了温度、pH值、时间、料液比及浸提级数对提取效果的影响 ,也探讨了酶法、三氯乙酸—正丁醇法及复合法去除蛋白的工艺条件。结果表明 :蛋白质去除最佳工艺为酶法和三氯乙酸—正丁醇复合法 ,美味牛肝菌多糖提取最佳工艺为加水 2 0倍 ,80℃ ,pH 8时浸提 1h ,多糖浸提率可达 7.37%。     

Ornatipolide,a Novel Phenolic Metabolite from the Basidiomycete,Boletus ornatipes

A novel phenolic metabolite, ornatipolide, was isolated from the Boletus ornatipes fungus. Its structure was established by a combination of spectroscopic and chemical methods, and by an X-ray crystallographic analysis.     

3种野生牛肝菌的菌塘土壤细菌多样性

【目的】以远东疣柄牛肝菌(Leccinum extremiorientale)、美味牛肝菌(Boletus edulis)和小孢粉孢牛肝菌(Tylopilus microsporus)菌塘为研究对象,揭示其菌塘土壤细菌的菌群多样性。【方法】通过高通量测序方法,分析这3种野生牛肝菌菌塘土壤细菌的菌群结构及多样性。【结果】远东疣柄牛肝菌菌塘土样中的主要细菌类群为变形杆菌门(53.6%)、酸杆菌门(33.8%)、拟杆菌门(4.7%)、放线菌门(1.7%);美味牛肝菌中主要类群为酸杆菌门(40.7%)、变形杆菌门(38.1%)、拟杆菌门(10.3%)、放线菌门(3.1%);小孢粉孢牛肝菌中酸杆菌门(65.3%)、变形杆菌门(23.8%)、拟杆菌门(4.9%)为主要类群。细菌在属级分类水平上,远东疣柄牛肝菌菌塘主要属中69.8%为未知属,其余为伯克氏菌属Burkholderia(16.0%)、酸杆菌门中的Candidatus Solibacter(5.9%)和酸孢菌属Acidocella(3.3%)。美味牛肝菌中主要的属分布在未知类群(83.0%),此外,还有Candidatus Solibacter(8.0%),伯克氏菌属Burkholderia(2.1%)。小孢粉孢牛肝菌菌塘中,分别为未知类群(80.9%)和Candidatus Solibacter(12.6%)。【结论】3种牛肝菌菌塘土壤中细菌类群具有丰富的多样性,其中含有大量未知类群。     

Key taste components in two wild edible Boletus mushrooms using widely targeted metabolomics

Compounds from wild edible mushrooms has been reported to exert biological activities and contribute to the different flavors of mushrooms in our diet. Wild edible Boletus mushrooms are popular in Southwest China. In this study, we performed ultra-performance liquid chromatography-electrospray ionization-tandem mass spectrometry (UPLC-ESI-MS/MS) based on widely targeted metabolomics analysis to identify key components. A total of 194 metabolites (113 upregulated, 81 downregulated) divided into 11 groups (49 metabolites in group lipids, 34 in amino acids and derivatives, 30 in organic acids, 18 in phenolic acids, 16 in nucleotides and derivatives, 13 in alkaloids, 6 in flavonoids, 3 in lignans and coumarins, 3 in tannins, 2 in terpenoids, and 20 in others) were found among Boletus bainiugan compared with B. subsplendidus. Through clustering analysis, principal component analysis (PCA), and orthogonal signal correction and partial least squares-discriminant analysis (OPLS-DA), different metabolites from fruiting bodies were clearly identified. Significant differences were observed in the metabolites between Boletus bainiugan and B. subsplendidus. These metabolites are involved in important biological functions. Our results provide new insights into important metabolites and theoretical basis for the taste difference of two wild edible Boletus mushrooms.     

A ribonuclease from the wild mushroom Boletus griseus

A ribonuclease (RNase) with a molecular mass of 29 kDa and cospecific for poly A and poly U was isolated from fruiting bodies of the mushroom Boletus griseus. Its N-terminal sequence exhibited some similarity to those of RNases from the mushrooms Irpex lacteus and Lentinus edodes. The RNase was adsorbed on diethylaminoethyl-cellulose, Q-Sepharose, and Affi-gel blue gel and was unadsorbed on CM-cellulose. The enzyme exhibited a temperature optimum between 60 and 70°C and a pH optimum at 3.5.     

云南美味牛肝菌ITS 区域结构特点

利用ITS 的通用引物(ITS5-ITS4) 对云南的美味牛肝菌( Boletus edulis) 子实体的DNA 进行PCR 扩增, 扩增产物回收后直接测序。序列的聚类分析表明, 在ITS1-5 . 8S rDNA-ITS2 区域, 云南的美味牛肝菌与欧洲的夏牛肝菌( B. aestivalis) 和铜色牛肝菌( B . aereus) 同源性较高, 但在ITS2 区域夏牛肝菌和铜色牛肝菌分别有一段美味牛肝菌没有的大小分别为73 bp 和26 bp 的特征序列。     

Isolation and sequence analysis of new peptaibol, boletusin, from Boletus spp.

A new peptaibol, boletusin, was isolated from the methanol extract of the fruiting body of the mushroom, Boletus spp. Sequential determination by positive FAB MS/MS showed that boletusin is a peptide consisting of 19 amino acids, with one acetylated N-terminus residue, phenylalanine, and a C-terminal amino alcohol, tryptophanol. This peptide showed antimicrobial activity against several Gram-positive bacteria.     

Purification and characterization of bolaffinine, a toxic protein from Boletus affinis Peck (Boletaceae)

A toxic protein of Mr 22,000, called bolaffinine, has been purified from the mushroom, Boletus affinis Peck (Boletaceae), with a 0.65% yield using a procedure involving four steps: ammonium sulfate precipitation, two chromatographies on ion-exchange columns and gel filtration on Sephadex G-75. It is thermolabile and can be inactivated by organic solvents. Its isoelectric point lies between pH 9 and 10. It contains 234 amino acids, no free SH groups and one disulfide bridge as evidenced by reactions with 5-5'-dithiobis-nitrobenzoate (DTNB) and 2-mercaptoethanol. When injected into mice, it provokes the death of animals within 16-24 h. The 24 h LD50 is 61 mg/kg of body weight. Bolaffinine inhibits protein synthesis in hepatoma tissue culture and in a rabbit reticulocyte lysate.     

云南美味牛肝菌ITS区域结构特点

利用ITS的通用引物（ITS5-ITS4）对云南的美味牛肝菌（Boletus edulis）子实体的DNA进行PCR扩增,扩增产物回收后直接测序。序列的聚类分析表明,在ITS1—5．8S rDNA-ITS2区域,云南的美味牛肝菌与欧洲的夏牛肝菌（B．aestivalis）和铜色牛肝菌（B．aereus）同源性较高,但在ITS2区域夏牛肝菌和铜色牛肝菌分别有一段美味牛肝菌没有的大小分别为73bp和26bp的特征序列。     

牛肝菌属卷边组Boletus sect. Appendiculati物种的分子识别

依据牛肝菌属卷边组Boletus sect. Appendiculati内7个物种的核糖体基因rDNA内转录间隔区（internal transcribed spacer,ITS）序列比对,设计5对ITS特异引物,分别用于卷边牛肝菌Boletus appendiculatus与亚卷边牛肝菌B. subappendiculatus、卷边牛肝菌与拟桃红牛肝菌B. pseudoregius、华靛牛肝菌B. roseoflavus与卷边牛肝菌B.?appendiculatus、华靛牛肝菌与华美牛肝菌B. speciosus、拟桃红牛肝菌与华美牛肝菌的相互识别。ITS区段的PCR扩增结果表明,5对ITS特异引物皆成功扩增出可用于辨别这些近缘物种的目的条带。但未能设计出ITS特异引物,以识别华靛牛肝菌与桃红牛肝菌B. regius两个近缘物种。