Fusarium spp. are plant pathogens, but can cause serious human infections. The clinical manifestations of fusarium disease are diverse, including skin infection and disseminated infection, and the diagnosis is often challengable. This article mainly reviews the manifestations of skin infection. Because natural drug resistance is commonly found in Fusarium species, disseminated fusariosis has a mortality rate of 80%-90%. A comprehensive understanding of the characteristics of fusarium is of great significance to clinicians. For setting the research strategy, this paper systematically reviews and analyzes related literature in Medline and Chinese Literature Database and comprehensively summarizes the pathogenic species, regional distribution, risk factors, pathological characteristics, clinical manifestations, drug sensitivity, diagnosis and treatment of fusariosis. This review is expected to be helpful to comprehensive understanding of the characteristics of fusariosis and disease diagnosis by clinicians.
Pseudoplectania sinica sp. nov., isolated from Huperzia serrata in Fujian Province, was identified based on morphological characteristics and molecular phylogenetic analysis of internal transcribed spacer (ITS) and nuclear large subunit ribosomal DNA (LSU rDNA). The holotype and ex-type cultures are deposited in Qilu Medical University (QLMU) and China General Microbiological Culture Collection Center (CGMCC).
In order to investigate the ecological distribution and colonization of dark septate endophytes (DSE) in the roots of Glycyrrhiza uralensis in the arid area of northwest China, soil samples and root samples were collected from Anxi and Minqin in Gansu, and Shapotou in Ningxia, in July 2018. Soil and root samples were collected in the limits of 0-10cm and 20-30cm around the main stem. The investigation showed that G. uralensis could be highly infected by DSE in different areas, forming typical dark colored septate hyphae and microsclerotia. The total DSE colonization rate in Anxi (43.34%) was significantly lower than that in Minqin (90%) and Shapotou (88.34%). The correlation analysis indicated that DSE colonization rate in roots of G. uralensis was significantly related to soil available phosphorus, organic carbon and alkaline phosphatase. Eleven genera and 13 species of DSE were isolated and identified, including Acrocalymma vagum, Alternaria longissima, Alternaria chlamydospora, Alternaria chlamydosporigena, Paraphoma chrysanthemicola, Darksidea alpha, Niesslia aemula, Tricharina ochroleuca, Acremonium nepalense, Fusarium solani, Preussia sp., Leptosphaeria oraemaris and Ulocladium sp. Acrocalymma vagum is dominant, being common in Minqin and Shapotou, while Anxi possesses the highest diversity of DSE, with seven species in total. Principal component analysis showed that in Anxi the species composition of DSE within the limits of 0-10cm was significantly different from that of 20-30cm. Single factor analysis of variance showed that the colonization rate of DSE hyphae in Anxi and Shapotou was significantly higher within the limits of 0-10cm from the main stem as compared with that within 20-30cm. There was a significant impact of plant cover degree on DSE community in desert ecological environment. Variation partitioning revealed that the colonization of DSE fungi was affected by the spatial distribution of sample plots, plant cover degree and soil factors (74.91%), while the species composition was more dependent on the heterogeneity of sample plots (84.46%) and soil nutrients (87.82%). Our results seem helpful to fully understand the function and significance of DSE in arid plant growth and vegetation restoration.
Cell wall polysaccharides were extracted by hot water extraction of superfine comminuted powder from water-extracted residue of Ganoderma sinense fruiting bodies. A high molecular weight polysaccharide GSCW30E-20E was purified by ethanol precipitation. The total sugar content of GSCW30E-20E determined by phenol-sulfate method was 98.03%. HPAEC results showed that its monosaccharide component is only glucose. The average molecular weight of GSCW30E-20E determined by HPSEC-MALLS-RI system was 1.552×10 6g/mol. Structure analysis by using infrared spectroscopy, methylation and NMR indicated that GSCW30E-20E was a beta-(1,3)-glucan linked to a glucose residue by a beta-(1,6)-glycoside bond. The degree of branching is 0.33.
Auricularia heimuer is one of the main edible fungi cultivated in China, with high economic and ecological value. RNA was extracted from different development stages (mycelium, primordium and fruiting stages) of A. heimuer straius (A14, A137 and A12) and subsequently reverse-transcribed into cDNA. Based on the whole-genome of A. heimuer, 12 candidate reference genes (APRTase, β-TUB, RPL2, EF-1a, EF-2, PGI, PGM, H +-ATPase, Tspd, 18S rRNA, 28S rRNA) were selected. The stability of each candidate reference gene, and the reference genes that could be stably expressed were selected for amplification using real-time fluorescence quantitative PCR (qRT-PCR) technology, and evaluation using geNorm, NormFinder, BestKeeper, and ΔCt algorithm and comprehensive evaluation software RefFinder. It was found that 18S rRNA, β-TUB, EF1-a, and 28S rRNA were suitable for regarding as internal reference gene combinations of different strains, and APRTase, 18S rRNA, and 28S rRNA as internal reference gene combinations of different growth stages.
Scedosporium aurantiacum is a common colonizer in patients with chronic lung diseases. In immunocompromised hosts dissemination may occur, often with fatal outcome. The mechanism of the fungal pathogenicity is unknown yet, hence there are lack of sufficient infection prevention and control (IPC) approaches. Facts have proved that trypsin-like protease secreted by the fungus may likely be a virulence factor through proteomic analysis and enzyme engineering technology. However, the genes, structures and pathogenesis of the protease are still unclear. In this work, the trypsin-like protease was purified using columns of Superdex S-200 and DEAE-Sepharose, and the product was analyzed using zymograms. Further studies on hydrolysis turned out that the protease preferred substrates bFSR, bLSTR, and bEKK to zFR and bzLR. The Km value of the fastest catalytic reaction was 6.09μmol/L, Vmax 13.01μmol/L/s and Kcat 23.65/s. The parameters of the slowest catalytic reaction were of Km 29.94μmol/L, Vmax 11.35μmol/L/s and Kcat 20.63/s. Drugs specifically designed for inhibiting the proteases seem important for prevention and control of S. aurantiacum infection.
The structure, antioxidant and antitumor activities of polysaccharides of Lentinula edodes from Zhejiang, Hubei and Xinjiang were analyzed. The crude polysaccharides were prepared by water extraction-alcohol precipitation, ZLP (polysaccharide of L. edodes from Zhejiang), XLP (polysaccharide of L. edodes from Xinjiang) and HLP (polysaccharide of L. edodes from Hubei) were obtained by Sevag and dialysis methods. The monosaccharide composition of three polysaccharides was determined by high performance anion exchange chromatography (HPAEC), and the structure of the polysaccharides was analyzed by fourier transform infrared spectrometer (FTIR). The free radical scavenging ability and inhibiting activity of tumor cell proliferation of the three polysaccharides also were measured. The results indicated that the three polysaccharides were mainly composed of glucose, galactose and mannose. The infrared absorption characteristics of the three polysaccharides were similar, and all of them contain β-glycosidic bonds. HLP, ZLP and XLP exhibited effective scavenging activities against 2,2-azino-bis-(3-ethylbenzothiazoline-6-sulfonic acid) (ABTS), 1,1-diphenyl-2-picrylhydrazyl (DPPH) and hydroxyl radicals. HLP and XLP showed higher inhibiting activity to proliferation of human hepatoma cells (HpG2), human gastric cancer cells (NCI-H460) and human gastric adenocarcinoma cells (SGC-7901) as compared to ZLP.
Pleurotus ostreatus was used as the material to study the differences of lignocellulolytic enzyme activities affected by different simple carbon and nitrogen sources and pure lignin. The results showed that the laccase, carboxymethyl cellulase and xylanase activities in P. ostreatus cultivated in the media with different carbon source and nitrogen source was significantly different (P<0.001), and the mycelial biomass obtained was also significantly different (P<0.001). Sucrose used as the main carbon source advantaged the enhancement of laccase activities. Fructose used as the main carbon source was favorable for enhancing carboxymethyl cellulase activities and accumulation of mycelial biomass. Glucose used as the main carbon source was favorable for enhancing of xylanase activities. The enhancement of laccase activities and the accumulation of mycelial biomass were advantaged by yeast extract used as the main nitrogen source. Potassium nitrate used as the main nitrogen source was favorable for enhancement of carboxymethyl cellulase activities. Ammonium sulfate used as the main nitrogen source was favorable for enhancement of xylanase activities. The existence of alkaline lignin was beneficial to the enhancement of laccase activities, but not to the accumulation of mycelial biomass. The presence of alkaline lignin did not promote carboxymethyl cellulase and xylanase activities.
Ganoderma lingzhi mycelia were obtained by liquid shaking-static two-stage fermentation method, and four triterpenes were isolated from the mycelia through silica gel column chromatography, reversed-phase column chromatography and methanol recrystallization. According to the analysis of spectral data of NMR and MS, these compounds were identified as lanosta-7,9(11),24-trien-3α-acetoxy-26-oic acid (1), ganoderic acid R (2), ganoderic acid T (3) and ganoderic acid S (4). The nuclear magnetic signals of compound 1 were reported for the first time. All of the four triterpenes showed good inhibitory activity on the proliferation of tumor cells L1210 and K562, and the in vitro antitumor activity of compound 1 was confirmed for the first time. IC50 values of compound 1 against tumor cells L1210 and K562 were 22.17μmol/L and 54.79μmol/L, respectively.
Lentinan is a macromolecule glucan extracted and purified from mycelia or fruiting bodies of Lentinula edodes, having biological activities of improving immunity, anti-virus, anti-oxidation and anti-fungus. In this study, physico-chemical properties and immunocompetence in vitro of polysaccharides of Lentinula edodes at different growth stages of fruiting bodies were compared and analyzed. The results showed that the content, physico-chemical properties and in vitro immunocompetence of crude polysaccharides varied with growth stage of fruiting bodies. The yield of crude polysaccharides first increased at early stage and high-yielded at gill-formation stage and then decreased. The content of crude polysaccharides showed the same trend, but the highest content appeared at mature stage. The molecular weight of polysaccharides varied greatly with growth stages. The proportion of polysaccharides with molecular weight of ten millions or more increased, while that with molecular weight of millions or less decreased at later stage. The monosaccharide components of polysaccharides at different stages were constantly fructose, galactose, glucose and mannose. All the polysaccharides obtained from different growth stages had good immunocompetence in vitro, of which those from button stage showed the highest activity at concentration of 500μg/mL. These results provided referential estimation for determination of harvest period and preparation of lentinan products.
Dictyophora indusiata, a kind of precious edible and medicinal fungus, has strong antimicrobial activity, and is expected to be used as natural preservative for food preservation. In this study, an antimicrobial component from D. indusiata was isolated and purified by solvent extraction, three times silica gel column chromatography with different mobile phase, one time reversed phase column chromatography and thin layer chromatography. This compound was identified as m-trihydroxybenzene by nuclear magnetic resonance spectroscopy (NMR) analysis. Using Bacillus magaterium and Salmonella enteritidis as test bacteria, the antibacterial effect of this compound was determined by plate perforation, in situ bacteriostasis and microscopic observation. The results showed that the compound had a strong inhibitory effect on the two bacteria, with semi-inhibitory concentration of 83.06g/mL and 51.58g/mL, respectively. Individual compound m-trihydroxybenzene with antibacterial activity is firstly obtained from D. indusiata and hopefully developable as natural antibacterial substances.
The endophytic fungus G18 isolated from the young blueberry fruits of Vaccinium ashei was identified as Schizophyllum commune based on morphological characteristics, ITS sequence analysis and phylogenetic analysis. The lignin-degrading activity of three enzymes, laccase, lignin peroxidase and manganese peroxidase, produced by S. commune G18 were monitored base on decolorization ability of G18 to eight dyes. The results showed that the strain G18 could decolorize all the tested eight dyes under solid conditions, and decolorization effect on malachite green dyes was the best. The decolorization conditions of G18 to malachite green was optimized. The medium adjusted at pH 7.0 containing 20.0g/L starch, 1.0g/L urea, and 1.0g/L zinc sulfate was the best for obtaining the cultures with high decolorization ability. Inoculation quantity of 9 tablets (d=5.0mm) of inoculum seems suitable.
Mycelium ethyl acetate extracts (EAE) of three Hypocrella strains were used to detect their antitumor, antibacterial and antioxidant activities, and to analyze their chemical compositions by GC-MS. The results showed that EAE of two Hypocrella strains exhibited strong inhibitory activities against HepG2 cell, with an IC50 value of less than 9μmol/L. Antibacterial test results indicated that EAE of two Hypocrella strains displayed inhibiting activities against Escherichia coli, Bacillus subtilis and Xanthomonas pruni. One tested Hypocrella strain possessed higher DPPH radical scavenging activities (scavenging rate up to 85%). GC-MS analyses showed that twenty-one, thirty-five and thirty-nine kinds of constituents were obtained from EAE of entomogenous Hypocrella JXJG201717, JXJG201720 and ARSEF7697, respectively, which were mainly esters, alcohols and acids. Both H. discoidea JXJG201720 and ARSEF7697 had thirteen same compounds. JXJG201720 and JXJG201717 shared seven same compounds. The present study unveiled that entomogenous Hypocrella was possessed of various bioactive components with antitumor, antibacterial and antioxidant properties, with multiple values of utilization.
Three wood-decaying pathogenic fungi, Inonotus weirii (Murrill) Kotlaba et Pouzar, Phellinus noxius (Corner) G.H. Cunn. and Rigidoporus lignosus (Klotzsch) Imaz., were listed as entry plant quarantine fungi by Ministry of Agriculture of P.R. China in 2007. Based on recent phylogenetic studies the taxonomic positions of these forest pathogens are changed dramatically, and Coniferiporia weirii (Murrill) L.W. Zhou & Y.C. Dai, Pyrrhoderma noxium (Corner) L.W. Zhou & Y.C. Dai, and Rigidoporus microporus (Sw.) Overeem are respectively accepted names for these fungi. In addition, Pyrrhoderma noxium and Rigidoporus microporus have a wide distribution in China, and they should be removed from the list of entry plant quarantine fungi.
