Four New Species and a New Combination of Boletaceae (Boletales) from Subtropical and Tropical China.

Previous studies have shown that boletes are abundant and diverse in China, especially in tropical and subtropical regions. In the present study, morphological, ecological, host relationship, and a four-locus (28S, tef1, rpb1, and rpb2) molecular phylogenetic analyses were used to study the family Boletaceae in subtropical and tropical China. Four new bluing species are described from three genera, viz. Boletellus verruculosus (Chinese name), Xerocomellus tenuis (Chinese name), Xer. brunneus (Chinese name), and Xerocomus zhangii (Chinese name). Moreover, the genus Nigroboletus is treated as a synonym of Xerocomellus, and a new combination, namely Xer. roseonigrescens (Chinese name), is proposed.

Green synthesis of silver nanoparticles using Phlebopus portentosus polysaccharide and their antioxidant, antidiabetic, anticancer, and antimicrobial activities.

Silver nanoparticles (AgNPs) by green synthesis from fungi polysaccharides are attracting increasing attention owing to their distinctive features and special applications in numerous fields. In this study, a cost-effective and environmentally friendly biosynthesizing AgNPs method with no toxic chemicals involved from the fruiting body polysaccharide of Phlebopus portentosus (PPP) was established and optimized by single factor experiment and response surface methodology. The optimum synthesis conditions of polysaccharide-AgNPs (PPP-AgNPs) were identified to be the reaction time of 140 min, reaction temperature of 94 °C, and the PPP: AgNO3 ratio of 1:11.5. Formation of PPP-AgNPs was indicated by visual detection of colour change from yellowish to yellowish brown. PPP-AgNPs were characterized by different methods and further evaluated for biological activities. That the Ultraviolet-visible (UV-Vis.) spectroscopy displayed a sharp absorption peak at 420 nm confirmed the formation of AgNPs. Fourier transform infrared (FTIR) analysis detected the presence of various functional groups. The lattice indices of (111), (200), (220), and (331), which indicated a faced-centered-cubic of the Ag crystal structure of PPP-AgNPs, was confirmed by X-ray diffraction (XRD) and the particles were found to be spherical through high resolution transmission electron microscopy (HRTEM). Energy dispersive X-ray spectroscopy (EDS) determined the presence of silver in PPP-AgNPs. The percentage relative composition of elements was determined as silver (Ag) 82.5 % and oxygen (O) 17.5 % for PPP-AgNPs, and did not exhibit any nitrogen peaks. The specific surface area of PPP-AgNPs was calculated to be 0.5750 m2/g with an average pore size of 24.33 nm by BET analysis. The zeta potential was -4.32 mV, which confirmed the stability and an average particle size of 64.5 nm was calculated through dynamic light scattering (DLS). PPP-AgNPs exhibited significant free radical scavenging activity against DPPH with an IC50 value of 0.1082 mg/mL. The MIC values of PPP-AgNPs for E. coli, S. aureus, C. albicans, C. glabrata, and C. parapsilosis are 0.05 mg/mL. The IC50 value of the inhibition of PPP-AgNPs against α-glucosidase was 11.1 µg/mL, while the IC50 values of PPP-AgNPs against HepG2 and MDA-MB-231 cell lines were calculated to be 14.36 ± 0.43 µg/mL and 40.05 ± 2.71 µg/mL, respectively. According to the evaluation, it can be concluded that these green-synthesized and eco-friendly PPP-AgNPs are helpful to improve therapeutics because of significant antioxidant, antimicrobial, antidiabetic, and anticancer properties to provide new possibilities for clinic applications.

Four New Species of Strobilomyces (Boletaceae, Boletales) from Hainan Island, Tropical China.

Strobilomyces, one of the most noticeable genera of Boletaceae (Boletales), is both ecologically and economically important. Although many studies have focused on Strobilomyces in China, the diversity still remains incompletely understood. In the present study, several collections of Strobilomyces from Hainan Island, tropical China were studied based on morphology and molecular phylogenetic analyses. Four species are described as new, viz. S. baozhengii, S. conicus, S. hainanensis, and S. pachycystidiatus. Detailed descriptions, color photos of fresh basidiomata, and line drawings of microstructures of the four species are presented.

Structural characterization, and in vitro hypoglycemic activity of a polysaccharide from the mushroom Cantharellus yunnanensis.

A polysaccharide CY-2 from C. yunnanensis was obtained through a process of consecutive water extraction, alcohol precipitation, and DEAE-52 fast-flow chromatography. CY-2, with an average molecular weight of 2.69 × 104 Da mainly consisted of glucose and mannose with a molar ratio of 33.5: 56.9. Infrared spectrum (IR), methylation analysis, and nuclear magnetic resonance (NMR) results revealed that CY-2 may have a backbone consisting of →6)-α-D-Manp-(1 â†’ 3)-ß-D-Glcp-(1→, and branch chain ß-D-Glcp-(1→. Meanwhile, CY-2 had a higher inhibition rate on α-glucosidase activity compared with other fractions (CY-0, CY-1, and CY-4) and was a mixed competitive inhibitor. In addition, CY-2 at the concentration of 10 µg/mL presented a superior power to improve glucose consumption and metabolism in HepG2 cells compared with metformin. Overall, these findings highlight the potential value of CY-2 as a hypoglycemic agent.

Extraction, Characterization, and In Vitro Hypoglycemic Activity of a Neutral Polysaccharide from the New Medicinal Mushroom Cantharellus yunnanensis (Agaricomycetes).

Polysaccharides serve as promising ingredients for health-beneficial functional foods, while there were no investigations into the structural characterizations and bioactivities of an edible mushroom Cantharellus yunnanensis. In the study, crude polysaccharides from this mushroom were extracted by hot water and isolated by ethanol precipitation. Then, a neutral polysaccharide (named CY-1) was purified from the crude polysaccharide by deproteinization with Sevag reagent, decolorization with a kind of macroporous adsorption resin SP-825, DEAE-52 cellulose column chromatography and dialysis. The physicochemical properties of CY-1 were characterized by UV, IR, SEM, NMR, and HPLC analyses. Structural characterizations revealed that CY-1 is a homogeneous heteropolysaccharide with an average molecular weight of 3.06 × 104 Da. CY-1 exhibited a honeycomb structure with an irregular branching shape, and it was composed of mannose, glucose, fucose, xylose, arabinose, galactose, rhamnose, and glucuronic acid, with molar fractions of 54.83%, 25.11%, 10.28% 4.53%, 2.12%, 1.64%, 0.83%, and 0.64%, respectively. In vitro hypoglycemic tests showed that CY-1 had an inhibitory effect on α-glucosidase. In addition, CY-1 of 160 µg/mL promoted glucose consumption in normal HepG2 cells. These results suggested that CY-1 may be a potential hypoglycemic agent.

Notes on four species of Russula subgenus Heterophyllidiae (Russulaceae, Russulales) from southern China.

Heterophyllidiae, one of the main subgenus of Russula (Russulaceae, Russulales), is both ecologically and economically important. Although many studies have focused on subgenus Heterophyllidiae in China, the diversity, taxonomy, and molecular phylogeny still remained incompletely understood. In the present study, two new species, R. discoidea and R. niveopicta, and two known taxa, R. xanthovirens and R. subatropurpurea, were described based on morphology and molecular phylogenetic analyses of ITS and 28S DNA sequences with new collections of subgenus Heterophyllidiae from southern China. Both morphological and phylogenetic analyses consistently confirmed that R. niveopicta and R. xanthovirens belong to the subsect. Virescentinae, R. discoidea and R. subatropurpurea come under subsect. Heterophyllae, and R. prasina is synonymized with R. xanthovirens.

Updated taxonomy of Chinese Cantharellus subgenera Afrocantharellus and Magni (Hydnaceae, Cantharellales): Three new taxa and amended descriptions of one previous species.

Cantharellus, one of the main genera of Hydnaceae (Cantharellales), is both ecologically and economically important. Although many studies have focused on this genus in China, the taxonomy should be further updated. In the present study, Cantharellus subgenera Afrocantharellus and Magni were investigated based on morphology and molecular phylogenetic analyses with new collections from China. Five phylogenetic species were recognized among the studied collections, three of which were described as new: C. bellus, C. cineraceus, and C. laevigatus; one was previously described taxon: C. hygrophoroides; and the remaining species was not defined due to the paucity of the materials. Among the four described species, both C. bellus and C. laevigatus are members of subgen. Magni, whereas C. cineraceus and C. hygrophoroides belong to subgen. Afrocantharellus.

Purification and Structure Characterization of the Crude Polysaccharide from the Fruiting Bodies of Butyriboletus pseudospeciosus and Its Modulation Effects on Gut Microbiota.

Polysaccharides from the species of Boletaceae (Boletales, Agaricomycetes, Basidiomycota) are economically significant to both functional foods and medicinal industries. The crude polysaccharide from Butyriboletus pseudospeciosus (BPP) was prepared, and its physicochemical properties were characterized through the use of consecutive experimental apparatus, and its impact on the gut microbiota of Kunming mice was evaluated. Analyses of the structure characteristics revealed that BPP was mainly composed of Man, Glc, and Gal, possessing the pyranose ring and ß/α-glycosidic linkages. TG analysis exhibited that BPP had great heat stability. The SEM observation performed demonstrated that BPP appeared with a rough, dense, and porous shape. Through the BPP intervention, the serum and fecal biochemical index in mice can be improved obviously (p < 0.05). The abundance of beneficial microbiota in the BPP-treated group was significantly increased, while the abundance of harmful microbiota was significantly decreased (p < 0.05). Based on the Tax4Fun, we also revealed the relationship between the species of gut microbiota and showed that the high dose of BPP has significantly changed the functional diversities compared with those in other groups (p < 0.05). The results suggest that B. pseudospeciosus could serve as potential functional food or medicine.

Preparation, structural characterisation, and antioxidant activities of polysaccharides from eight boletes (Boletales) in tropical China.

Polysaccharides in boletes (Boletales) are economically significant to both function food and medicinal industries. The polysaccharides were extracted from the fruit bodies of eight boletes, namely, Aureoboletus longicollis, Butyriboletus hainanensis, Crocinoboletus rufoaureus, Hemioporus japonicus, Neoboletus infuscatus, Neoboletus obscureumbrinus, Tylopilus otsuensis, Xanthoconium fusciceps, which were collected from tropical China; their physicochemical properties and antioxidant activities were characterised and evaluated, respectively. The results revealed that the polysaccharides among the eight boletes were mainly composed of glucose, mannose, and galactose, with a broad molecular weight range, and contained a pyranose ring revealed by FT-IR and NMR spectral analyses. Many factors such as different species of boletes, geographic conditions, molecular weight, configuration, and monosaccharide content may affect the antioxidant power of polysaccharides, simultaneously, instead of one single factor. The antioxidant activities of the polysaccharides were measured according to in vitro assays of DPPH scavenging, superoxide anion scavenging, and ferrous ion reducing tests. The polysaccharide of C. rufoaureus has greatly superior antioxidant activity and it could serve as potential functional food or medicine.

A Contribution to Knowledge of Craterellus (Hydnaceae, Cantharellales) in China: Three New Taxa and Amended Descriptions of Two Previous Species.

Species of Craterellus (Hydnaceae, Cantharellales) in China are investigated on the basis of morphological and molecular phylogenetic analyses of DNA sequences from nuc 28S rDNA D1-D2 domains (28S) and nuc rDNA internal transcribed spacer ITS1-5.8S-ITS2 region. Five species are recognized in China, of which three of them are described as new, viz. C. fulviceps, C. minor, and C. parvopullus, while two of them are previously described taxa, viz. C. aureus, and C. lutescens. A key to the known Chinese taxa of the genus is also provided.

A New Muscarine-Containing Inosperma (Inocybaceae, Agaricales) Species Discovered From One Poisoning Incident Occurring in Tropical China.

Currently, mushroom poisoning still poses a huge problem to humans' health and life globally. Poisoning incidents caused by Inosperma spp. were reported continuously in tropical China in recent years. In this study, a new poisonous Inosperma species, discovered from a poisoning incident, was described in tropical China based on morphological, molecular, and toxin detection evidence; detailed descriptions, photographs, and comparisons to closely related species were provided. For qualitative analysis, through targeted screening using ultra-high liquid chromatography triple quadrupole mass spectrometry (UPLC-MS/MS), the new species contains muscarine and no other toxins (two isoxazole derivatives, two tryptamine alkaloids, three amatoxins, and three phallotoxins). For quantitative analysis, muscarine contents in the pileus and the stipe were 2.08 ± 0.05 and 6.53 ± 1.88 g/kg, respectively.

Morphological and Phylogenetic Evidences Reveal Four New Species of Cantharellus Subgenus Cantharellus (Hydnaceae, Cantharellales) From China.

Species of Cantharellus subgenus Cantharellus are interesting and important for their mycorrhizal properties, medicinal values, and edibility. In China, there are many undescribed species of the subgenus. In this study, four new species of subg. Cantharellus, viz. Cantharellus albopileatus, Cantharellus chuiweifanii, Cantharellus pinetorus, and Cantharellus ravus from Hainan and Hunan Provinces, respectively, were described based on morphological and phylogenetic evidence as a contribution to the knowledge of the species diversity in China. Detailed descriptions, color photographs of fresh basidiomata, and line drawings of microstructures of these four new species are presented as well as comparisons with related species.

Rubroboletus flammeus (Boletaceae, Boletales), a novel species unveiled from subtropical China based on morphological and phylogenetic evidences.

Rubroboletus flammeus is described as a new species from subtropical China based on morphological and molecular phylogenetic analyses. It is morphologically characterized by a red to fiery-red basidioma with a dry pileus, a context in pileus white but that in stipe bright yellow, a stipe densely covered with spots, a blue color change of tissues, and a trichoderm-type pileipellis. Detailed descriptions, color photographs of fresh basidiomata, and line drawings of microscopic features of the new species are presented. A key to the known Chinese taxa of Rubroboletus is provided.

Chemical profiles and health-promoting effects of porcini mushroom (Boletus edulis): A narrative review.

Boletus edulis is an edible mushroom with nutritious, delicacy, and pharmacological properties. It is rich in carbohydrates, proteins, minerals, and taste compounds, while low in fat and calories. Diverse bioactive compounds, including polysaccharides, phenolic compounds, and phytosterols, have been found in B. edulis. In addition, bioactive compounds and chemical extracts from B. edulis have been verified to possess constipation prevention, antioxidant, antineoplastic, anti-inflammatory, hepato-protective, antibacterial, and antiviral activities. This paper provides an overview of B. edulis research in recent two decades, emphasizing the nutrition constituents, taste and flavor components, bioactive compounds, and health-promoting effects of B. edulis. Boletus edulis appeared to have health-promoting effects that may effectively prevent or treat various chronic diseases. The potential of B. edulis as a functional food and medicine needs to be further investigated and confirmed.

Notes on Amanita section Validae in Hainan Island, China.

Hainan is the second largest island in China with the most extensive and well-preserved tropical forests and is also the largest island of the Indo Burma Biodiversity Hotspot. It provides in situ conservation for the unique ecosystem of the island. Recent studies have shown that there are diverse fungal species in Hainan. In this study, about 40 collections of the genus Amanita have been studied based on the morphology and molecular systematics, including 35 Chinese specimens (24 from Hainan, and eleven from other regions) and three specimens from other countries (Singapore and Malaysia). In total, five new species belonging to Amanita section Validae are described: A. cacaina, A. parvigrisea, A. pseudofritillaria, A. pseudosculpta, and A. yangii. Amanita parvifritillaria is recorded for the first time in Hainan. It is also the first report of this fungus occurring, outside Yunnan Province, China. Among the five new species, two are unique in this section because of the appendiculate pileus margin and the absence of an annulus. Based on these new findings, the diagnosis of the section Validae should be slightly modified to include a few species with appendiculate margin and the lack of annulus.

Two new Inosperma (Inocybaceae) species with unexpected muscarine contents from tropical China.

An accurate identification of poisonous mushrooms and the confirmation of the toxins involved are both of great importance in the treatment of mushroom poisoning incidents. In recent years, cases of mushroom poisoning by Inosperma spp. have been repeatedly reported from tropical Asia. It is urgent to know the real species diversity of Inosperma in this region. In the present study, we proposed two new Inosperma species from tropical Asia, namely I.muscarium and I.hainanense. They were described based on morphology and multilocus phylogeny. Detailed descriptions, color photographs and the discussion with other closely related species of the two new taxa were provided. In addition, a comprehensive muscarine determination of these two new species using ultrahigh performance liquid chromatography tandem mass spectrometry (UPLC-MS/MS) approach has been performed. Results showed that these two species were muscarine positive, with a content of 16.03 ± 1.23 g/kg in I.muscarium and a content of 11.87 ± 3.02 g/kg in I.hainanense, much higher than the known species I.virosum. Recovery of muscarine ranged from 93.45% to 97.25%, and the average recovery is 95.56%.

Neoboletus infuscatus, a new tropical bolete from Hainan, southern China.

Neoboletus infuscatus (Boletaceae, Boletales) is described as a new species from Yinggeling of Hainan Tropical Rainforest National Park, southern China. It is morphologically characterized by a large basidioma with a nearly glabrous, brownish yellow, yellowish brown to pale brown pileus, pores orangish red when young, yellowish brown to brown when old, context and hymenophore staining blue when injured, a yellow stipe with red punctuations, surfaces of the pileus and the stipe usually covered with a thin layer of white pruina when young. Phylogenetic analyses of DNA sequences from part of the 28S gene, the nuclear rDNA internal transcribed spacer (ITS) region, and part of the translation elongation factor 1-α gene (TEF1) also confirm that N. infuscatus forms an independent lineage within Neoboletus. Detailed morphological description, color photos of fresh basidiomata and line-drawings of microstructures are provided.

Hygrophorus subsection Hygrophorus (Hygrophoraceae, Agaricales) in China.

Hygrophorus subsect. Hygrophorus has been relatively well-studied in Europe and North America, but studies on the taxa in Asia, particularly in China, are still limited. In this study, phylogenetic overviews of genus Hygrophorus, based on the nuclear large subunit (LSU) ribosomal RNA gene and of subsect. Hygrophorus, based on the nuclear ribosomal internal transcribed spacer (ITS) regions were generated. Four new species, i.e. H. brunneodiscus, H. fuscopapillatus, H. glutiniceps and H. griseodiscus are described from southern China; and a rarely reported edible species H. hedrychii is described in detail, based upon the materials from north-eastern China. The main characteristics of the species under subsect. Hygrophorus worldwide are summarised in a table.

Phylogenetic overview of Aureoboletus (Boletaceae, Boletales), with descriptions of six new species from China.

In this study, species relationships of the genus Aureoboletus were studied, based on both morphological characteristics and a four-gene (nrLSU, tef1-a, rpb1 and rpb2) phylogenetic inference. Thirty-five species of the genus have been revealed worldwide, forming eight major clades in the phylogenetic tree, of which twenty-four species have been found in China, including six new species: A. glutinosus, A. griseorufescens, A. raphanaceus, A. sinobadius, A. solus, A. velutipes and a new combination A. miniatoaurantiacus (Bi & Loh) Ming Zhang, N.K. Zeng & T.H. Li proposed here. A key to 24 known Chinese species has been provided.

New and noteworthy boletes from subtropical and tropical China.

The morphology, ecology, and phylogenetic relationships of specimens of the family Boletaceae from subtropical and tropical China were investigated. Four species, Butyriboletushuangnianlaii, Lanmaoamacrocarpa, Neoboletusmultipunctatus, and Sutoriussubrufus, are new to science. Chalciporusradiatus and Caloboletusxiangtoushanensis are redescribed. Caloboletusguanyui is proposed to replace Boletusquercinus Hongo, an illegitimate later homonym. The recently described Tylopiluscallainus is synonymized with the Japanese Boletusvirescens, and the new combination T.virescens (Har. Takah. & Taneyama) N.K. Zeng et al. is proposed. Moreover, Neoboletus is treated as an independent genus based on evidence from morphology and molecular phylogenetic data in the present study, and many previously described taxa of Sutorius are recombined into Neoboletus: N.ferrugineus (G. Wu et al.) N.K. Zeng et al., N.flavidus (G. Wu & Zhu L. Yang) N.K. Zeng et al., N.hainanensis (T.H. Li & M. Zang) N.K. Zeng et al., N.obscureumbrinus (Hongo) N.K. Zeng et al., N.rubriporus (G. Wu & Zhu L. Yang) N.K. Zeng et al., N.sanguineoides (G. Wu & Zhu L. Yang) N.K. Zeng et al. , N.sanguineus (G. Wu & Zhu L. Yang) N.K. Zeng et al., and N.tomentulosus (M. Zang et al.) N.K. Zeng et al.