Mycoparasitism of Nematode-Trapping Fungus Monacrosporium ellipsosporumand Its Biochemical Basis

Monacrosporium ellipsosporum, a nematode-trapping fungus, was isolated by baiting with sclerotiaof Sclerotinia sclerotiorum in soil from a tobacco field in Yuxi, Yunnan Province. Colonizationfrequency of the sclerotia by the fungus was 18% in natural soil. Reinoculation tests byplacing surface-sterilized sclerotia on fungal cultures for two weeks and then surface-sterilized again led to 32% sclerotia be infected. Dual culture tests in PDA plates did notgive rise to a suppression zone between the colonies of M. ellipsosporum and its counterpartfungi S. sclerotiorum and Rhizoctonia solani, suggesting there was little or no nutritionalcompetition and absent of antifungal compounds. However, M. ellipsosporum could grow overabsent of S. sclerotiorum and R. solani, and significantly inhibited their growth on agarplates. Scanning electron and light microscopic observations showed that hyphae of M. ellipsosporumgrew along and appressed on hypha of S. sclerotiorum and coiled around hyphae of R. solani.Assays of cell wall-degrading enzymes showed that M. ellipsosporum grew well in chitin agarmedia, with clear transparent hydrolysis zones. Activities of total chitinase, exo-chitinase,β-1, 3-glucanase and protease were 140.2±11.9, 82.9±4.1, 111.2±7.6 and 76.1±4.3 U respect-ively, after incubation for 4 days at 30 ℃ in liquid media containing ground sclerotia of S.sclerotiorum as sole nutrient source. These enzymes might be important in the mycoparasiticactivity of M. ellipsosporum.

Study on the Biological Diversity of Nematode-trapping Fungi in Erhai Lake

[Objective]The research aimed to investigate the biological diversity of nematode-trapping fungi in the sediment of Erhai Lake.[Method]616 pieces of sediments were collected from Erhai Lake.The traditional classification and identification methods were used to isolate,purify and identify.[Result]3 genera and 22 species of nematode-trapping fungi were isolated.Arthrobotrys oligospora,A.musiformis and Dactylella leptospora were the dominant species,and their detection rates were 28.05%,16.04% and 8.92% respectively.By analyzing the diversity of nematode-trapping fungi in four seasons,it was found that the biological diversity was richer in summer,spring and autumn,and the diversity indexes were 2.59,2.47 and 2.34 respectively.The diversity index in winter was 1.48 and was lower.Species forming the adhesive nets were predominant;positive rate was 41.00%.[Conclusion]The rich nematode-trapping fungi resource existed in Erhai Lake,and its biological diversity had the seasonal variation characteristic.The nematode-trapping fungi which formed the viscous net were the dominant species in Erhai Lake.

Classification of dendrocola nematode-trapping fungi

Pine wilt disease,caused by Bursaphelenchus xylophilus and Bursaphelenchus mucnatus,is a serious quarantined disease.Arboreal nematode-trapping fungi of P inus spp.are effective predators on nematodes and have strong host adaptability.The development of these fungal resources may be an effective way to control pine wood nematodes.We collected 515 samples of pine wilt disease from the areas of Ninghai City(Zhejiang province),Shuangbai County(Yunnan province),and Daxing'anling(Heilongjiang province),China.Through isolation,culture and identification,6 species of nematode-trapping fungi(A rthrobotrys cladodesr,A.oligospora,A.musiformis,A.dendroides,Dactylellina ellipsospora,Monacrosporium thaumasium)were identified for predation against B.xylophilus,and 9 species(Arthrobotrys dactyloides,A.cladodes r A.oligospora A.dendroides,Dactylellina ellipsospora,Dactylella asthenopaga,D.leptospora,Arthrobotrys superba,Monacrosporium drechseri)were identified for predation against B.mucnatus.This study provides information in the classification of arboreal predator nematodes and provides an important basis for future biological control of pine wood nematodes.

Synergistic effects of the entomopathogenic fungus Isaria javanica and low doses of dinotefuran on the efficient control of the rice pest Sogatella furcifera

The rice planthopper,Sogatella furcifera,is a piercing-sucking insect pest of rice,Oryza sativa.It is responsible for significant crop yield losses,and has developed moderate to high resistance to several commonly used chemical insecticides.We investigated the effects of the insect fungal pathogen Isaria javanica,alone and in combination with the chemical insecticide dinotefuran,on S.furcifera under both laboratory and field conditions.Our results show that I.javanica displays high infection efficiency and mortality for different stages of S.furcifera,reducing adult survival,female oviposition and ovary development.Laboratory bioassays showed that the combined use of I.javanica with a low dose(4-16 mg L^(-1))of dinotefuran resulted in higher mortality in S.furcifera than the use of I.javanica or dinotefuran alone.The combined treatment also had more significant effects on several host enzymes,including superoxide dismutase,catalase,peroxidase,and prophenol oxidase activities.In field trials,I.javanica effectively suppressed populations of rice planthoppers to low levels(22-64%of the level in untreated plots).Additional field experiments showed synergistic effects,i.e.,enhanced efficiency,for the control of S.furcifera populations using the combination of a low dose of I.javanica(1×10^(4) conidia mL^(-1))and a low dose of dinotefuran(~4.8-19.2%of normal field use levels),with control effects of>90%and a population level under 50 insects per 100 hills at 3-14 days post-treatment.Our findings indicate that the entomogenous fungus I.javanica offers an attractive biological control addition as part of the integrated pest management(IPM)practices for the control of rice plant pests.

Bioactive chemical constituents from the marine-derived fungus Cladosporium sp.DLT-5

A new isochromanone,cladosporinisochromanone(1),accompanied by 15 known compounds(2–16)were obtained from secondary metabolites produced by marine-derived fungus Cladosporium sp.DLT-5.NMR and HRESIMS spectra elucidation determined the planar structure of 1.Subsequent electronic circular dichroism(ECD)experiment assigned the absolute configuration of 1.Compounds 1,2,4–6,and 10 displayed different degrees of neuroprotective activities on human neuroblastoma cells SH-SY5Y.Five compounds(1,3–5,and 13)emerged resistance to protein tyrosine phosphatase 1B(PTP1B),further kinetic analysis and molecular docking study indicated that the most potent compound 13(IC50value of 10.74±0.61μmol/L)was found as a noncompetitive inhibitor for PTP1B.Surface plasmon resonance(SPR)and molecular docking studies also demonstrated the interaction between compound 12 and Niemann-Pick C1 Like 1(NPC1L1),which has been identified as significant therapeutic target for hypercholesteremia.In addition,compounds 3,6,and 14 showed attractive inhibitory activity against the phytopathogenic fungi:Colletotrichum capsici.Therefore,library of Cladosporium metabolites is enriched and new active uses of known compounds are explored.

Discovery and Application of the Companion Fungus Related to Sclerotial Formation from Hyphae of Grifola umbellata

The companion fungus ( Grifola sp.) related to sclerotial formation from hyphae of Grifola umbellata (Pers.) Pilat was isolated from the cavity associated with sclerotia of G. umbellata in natural condition. Experimental results showed that the pure culture of G. umbellata was unable to form sclerotia, whereas sclerotia produced easily in flasks or on trunks when the companion fungus was inoculated together with strain of G. umbellata. The companion fungus is critical for sclerotium formation from hyphae of G. umbellata. Morphological differences were found in cultures of the two fungi. The companion fungus possesses thin-walled narrow hyphae, while G. umbellata is of wider hyphae which are either thick- or thin-walled.

White-rot Fungus Growth Conditions and Its Metabolic Kinetic Models

To investigate the growth conditions of white-rot fungus and simulate its metabolism kinetic models, the rules how the factors such as biomass, culture fluid, pH value, glucose consumption and exopolysaccharides generation, etc., changed during the batch culture process of white-rot fungi by using an air-lift fermenter, as well as metabolic kinetics of white-rot fungi were studied. Based on Logistic equation, Luedeking-Piret equation and experimental data, the correlation model parameters of mycelia biomass, glucose consumption and exopolysaccharide generation were obtained and found to be change with time in metabolism process. Detailedly, μm=0.071 8 h-1,α= 0.831 8 g/(g·h), β= 0.002 g/(g·h), b1=0.016 3 g/(g·h) and b2=3.023 3 g/(g·h). Hence the mycelial growth kinetic model, exopolysaccharide generation kinetic model and substrate consumption kinetic model which describe fermentation process of white-rot fungi were established. Meanwhile, the experimental data were verified by this model, and a good fitting result with an average relative error less than 10% between the data obtained from experiments and the model was yielded. The results show that these models can predict the growth and metabolic rules of white-rot fungus, the fermentation process of exopolysaccharides and the kinetic mechanism of white-rot fungus accurately.

Effects of Inoculation of Arbuscular Mycorrhizal Fungus and Apophysomyces spartina on P-uptake of Castor Oil Plant(Ricinus communis L.) and Rhizosphere Soil Enzyme Activities under Salt Stress

[Objective] In order to explore the mechanism of combined inoculation mi- croorganisms in improving coastal saline soil property and plant growth. [Method] The pot experiment was used to assess the effects of different inoculated proportion of arbuscular mycorrhizal fungi （AMF） and Phosphate-sotubilizing fungus. Apophysomyces spartina, on growth, chlorophyll contents, P-uptake of castor bean （Ricinus communis L.） and rhizosphere soil pH values, available P concentrations, enzyme activities. [Result] The mixed inoculation of AMF and A. spartina significantly reduced soil pH value, increased soil available phosphorous contents, improved the activities of soil invertase, urease, neutral phosphatase, and alkaline phosphatase. Chlorophyll contents, P-uptake, and plant dry weight of castor bean were also in- creased. The optimal proportion of the number of AMF spores to A. spartina colonies was 28.56：11.5×10^5, which had positive effects on saline soil and could stimulate plant growth under greenhouse condition. [Conclusion] Appropriate propor- tion of AMF and A. spartina had the potential to enhance coastal saline soil prop- erty and promote castor bean growth.

ATB FUNGUS 2法在念珠菌属和新生隐球菌抗真菌药敏试验中应用的评价

目的评价ATB FUNGUS 2半固体培养基法在测定念珠菌属和新生隐球菌对4种常用抗真菌药物敏感性中的应用价值。方法利用CLSI M27-A2微量液基稀释法和ATB FUNGUS 2法同时测定131株念珠菌和20株新生隐球菌对两性霉素B(AmB)、氟康唑(FLC)、氟胞嘧啶(5-FC)和伊曲康唑(ITC)的敏感性。结果两种方法对于AmB、5-FC、FLC和ITC的一致性分别为98%、89.4%、78.8%和78.1%。②所有受试菌株中两种方法的一致性为80%;但ATB FUNGUS2法将2/5株M27-A2法检查为FLC耐药的白念珠菌判断为敏感或剂量依赖,将8/10株M27-A2法检查为FLC剂量依赖的白念珠菌判断为敏感或耐药。③ATB FUNGUS 2法中AmB的MIC值判读范围偏高,以致于实际工作中不能读出准确的值。结论ATB FUNGUS 2半固体培养基法在测定念珠菌属和新生隐球菌对4种常用抗真菌药物的敏感性时不失为简单、快速而且重复性好的方法。

改良ATB Fungus 3法检测糠秕马拉色菌对抗真菌药物的敏感性

目的用改良ATB Fungus 3法测定糠秕马拉色菌的药物敏感性,以了解临床患者呼吸道分离的糠秕马拉色菌对常用抗真菌药物的最低抑菌浓度(MIC)。方法在ATB F2半固体培养基中添加0.5%吐温40和0.5%吐温60,用ATB Fungus 3药敏板条对47株临床分离的糠秕马拉色菌进行MIC检测。结果氟康唑MIC50为>128μg/mL,MICRange为≤1.0～>128μg/mL;5-氟胞嘧啶MIC50为>16μg/mL,MICRange为>16μg/mL;沃尔康唑MIC50为8.0μg/mL,MICRange为≤0.06～>8.0μg/mL;两性霉素B MIC50为4.0μg/mL,MICRange为≤0.5～16μg/mL;伊曲康唑MIC50为1.0μg/mL,MICRange为≤0.125～4.0μg/mL。呼吸道分离的糠秕马拉色菌对5种抗真菌药物的MIC值高于健康人皮肤分离的糠秕马拉色菌及标准菌株ATCC14521。结论改良ATB Fungus 3法操作简便,结果重复性好且易观察。糠秕马拉色菌MIC值的升高可能与患者使用抗真菌药物有关。

Cultivation of Black Fungus under Forest in Middle-high Altitude Areas

[Objective] The study was to solve the contradiction between fungus and forest during the production of black fungi, and to obtain relatively high economic benefits and ecological benefits. [Method] Black fungi were cultivated in forest with middle-high altitude of 500-1 600 m. The germination time of fungus stick, germination days of buds, growth days of fruiting body, commodity exterior, marketing effect and biological efficiency of black fungi were investigated. [Result] Compared with traditional cultivation, black fungus products cultivated under forest had the taste and flavor of wild black fungus. Fungus chaff wastage was directly decomposed by the roots in forest land, improving the soil structure of forest land. The need of moisture retention and the frequent access of administrative staff reduced the probability of forest fire occurrence. [Conclusion] Cultivation of black fungus under forest saves more than 70% fixed-asset investment on fungus shed, and the biological efficiency reached 12.2%.

Metabolites of Marine-derived Mangrove Endophytic Fungus #2492 from the South China Sea

Two metabolites （A and B） were isolated from the mycelium of mangrove endophytic fungus Stysanus like sp. （#2492） from the South China Sea. Their structures were identified by spectral data as N-（2-hydroxytetracosyl）-2-amino-1,3,4-trihydroxyoctadecane （A） and γ -stearolactone （B）. It is the first report that γ -stearolactone （B） is isolated from marine fungus as natural product.

Molecular Cloning of Early-expressed cDNAs from Rice in Response to Infection by Rice Blast Fungus Magnaporthe grisea

Compatible and incompatible reactions in rice plants ( Oryza sativa L. cv. Shenxianggen No.4) were resulted from inoculation with two different virulent races of rice blast fungus ( Magnaporthe grisea (Hebert) Barr), and thus an effective infecting system was established between rice plants and the rice blast pathogen. Two cDNA clones that showed induced and temporal patterns in expression in the very early stage in response to infection of the fungus were obtained from the plants by use of differential display. Of the two cDNA clones, Fastresp_a was induced to express in both compatible and incompatible interactions although it was expressed earlier in the former reaction. The second one, Fastresp_b , was only expressed in incompatible interaction. Southern blot analysis of the rice genomic DNA indicated that both of the two clones were from genome of the plant. No significant homology to the two genes was found from the rice gene database. This suggested that they were novel genes in rice and may play important roles in rice resistant response to infection of rice blast fungus.

An Abietane Diterpene and a Sterol from Fungus Phellinus igniarius

A new abietane diterpene 12-hydroxy-7-oxo-5, 8, 11, 13-tetraene-18, 6-abietanolide, together with a new natural sterol stigmasta-7, 22-diene-3β, 5α 6α-triol have been isolated from the fruiting body of the fungus Phellinus igniarius. Their structures were elucidated by spectroscopic methods including 2D NMR techniques.

Biodegradation of Gaseous Chlorobenzene by White-rot Fungus Phanerochaete chrysosporium

Objective To evaluate the effect of white rot fungus Phanerochaete chrysosporium on removal of gaseous chlorobenzene. Methods Fungal mycelium mixed with a liquid medium was placed into airtight bottles. A certain amount of chlorobenzene was injected into the headspace of the bottles under different conditions. At a certain interval, the concentrations in the headspace were analyzed to evaluate the degradation of chlorobenzene by P. chrysosporium. Results The degradation effects of P. chrysosporium on chlorobenzene under different conditions were investigated. The difference in the optimum temperature for the growth of the fungi and chlorobenzene degradation was observed. The data indicated that a lower temperature （28℃） would promote the degradation of chlorobenzene than the optimum temperature for the growth of the fungi （37℃）. A low nitrogen source concentration （30 mg N/L） had a better effect on degrading chlorobenzene than a high nitrogen source concentration （higher than 100 mg N/L）. A high initial concentration （over 1100 mg/m3） of chlorobenzene showed an inhibiting effect on degradation by P chrysosporium. A maximum removal efficiency of 95% was achieved at the initial concentration of 550 mg/m3. Conclusion P. chrysosporium has a rather good ability to remove gaseous chlorobeuzene. A low nitrogen source concentration and a low temperature promote the removal of chlorobenzene by P. chrysosporium. However, a high initial chlorobenzene concentration can inhibit chlorobenzene degradation.

Isolation and efficacy of entomopathogenic fungus(Metarhizium anisopliae)for the control of Aedes albopictus Skuse larvae:suspected dengue vector in Pakistan

Objective:To isolate the entomopathogenic fungus Metarhixium anisopliae(M.anisopliae) in the local environment,and evaluate its efficacy against the suspected dengue vector Aedes albopictus in Pakistan.Methods:According to the standard procedure,M.anisopliae was isolated from the dead mosquitoes which were collected from the field or dead after the collection.Bioassay was performed to determine its efficacy.Results:The results indicated that M.anisopliae had larvicidal effect with LC,value 1.09×10~5 and LC_(50) value 1.90×10^(13) while it took 45.41 h to kill 50% of tested population.Conclusions:Taking long time to kill 50%population when compare with the synthetic insecticides,is the only drawback for the use of entomopathogenic fungus but these bio-pesticides are safe for the use.

Immunomodulatory effects of polysaccharides from edible fungus:a review

The polysaccharides from edible fungus showed many kinds of biological activities,including anti-tumor,immunomodulatory,anti-inflammatory,anti-diabetes,improving functional constipation activities.In particular,the immunomodulatory effects have been paid more and more attention by scholars,but there was no systematic introduction of their immunomodulatory mechanism.So,this review introduced the immunomodulatory effects and mechanism of edible fungus polysaccharides in recent years,and then the relationships between structure and immunomodulatory effect were also discussed.

Purification,initial characterization and immune activities of polysaccharides from the fungus,Polyporus umbellatus

Polyporus umbellatus(formerly Grifola umbellatus),an edible fungus,has been used as traditional Chinese medicine.The present investigation aimed to uncover the active ingredients in this fungal species,with the emphasis on its polysaccharides.Two polysaccharides,one from fermented mycelium and the other from the fruiting body,were chromatographically purified.Molecular weights,anti-microbial and immune activities of the polysaccharides were determined.The mycelium polysaccharide was found to have a molecular weight of 857 kDa and consist of glucose and galactose at a molar ratio of 1.57:1,while the one from the fruiting body,679 kDa in molecular weight,was also made up of glucose and galactose but at a molar ratio of 5.42:1.In immune assays,these fungal polysaccharides increased the killing potency of natural killer(NK)and lymphokineactivated killer(LAK)cells from mouse spleen and promoted proliferation of mouse B and T cells.Additionally,both P.umbellatus mycelium and its extract were found to inhibit Escherichia coli and Staphylococcus aureus,but had no effects on Aspergillus niger or Aspergillus nidulans.These results indicated that fermented P.umbellatus mycelium is indeed immune active,most probably due to its ingredients of polysaccharides.The consumption of this fungus may be beneficial for human health.

Three new aspochalasin derivatives from the marine-derived fungus Spicaria elegans

Three new aspochalsins（R-T）（1-3） were isolated from the marine-derived fungus Spicaria elegans.Their structures were elucidated on the basis of comprehensive spectral analysis including 1D and 2D NMR techniques,and HR-ESI-MS.

Chemical constituents of marine mangrove-derived endophytic fungus Alternaria tenuissima EN-192

A chemical investigation of the ethyl acetate extract of the fermentation broth of Alternaria tenuissima EN- 192, an endophytic fungus obtained from the stems of the marine mangrove plant Rhizophora stylosa, resulted in the isolation of nine known secondary metabolites, including four indole-diterpenoids： penijanthine A （1）, paspaline （2）, paspalinine （3）, and penitrem A （4）; three tricycloalternarene derivatives： tricycloalternarene 3a （5）, tricycloalternarene lb （6）, and tricycloalternarene 2b （7）; and two alternariol congeners： djalonensone （8） and alternariol （9）. The chemical structures of these metabolites were characterized through a combination of detailed spectroscopic analyses and their comparison with reports from the literature. The inhibitory activities of each isolated compound against four bacteria were evaluated and compounds 5 and 8 displayed moderate activity against the aquaculture pathogenic bacterium Vibrio anguillarum, with inhibition zone diameters of 8 and 9 mm, respectively, at 100 gg/disk. To the best of our knowledge, this is the first report on the secondary metabolites of mangrove-derived Alternaria tenuissima and also the first report of the isolation ofindole-diterpenoids from fungal genus Alternaria.