暗色丝孢菌研究I.——两个中国新记录属和三个中国新记录种*

报道了暗色丝孢菌的三个中国新记录种:Beltraniellaportoricensis、Spadicoidesxylogena和Periconiacircinata,其中Beltraniella和Spadicoides两属在中国首次发现。研究的标本保藏于山东农业大学植物病理标本室(HSAUP)。     

暗色丝孢菌研究 I.两个中国新记录属和三个中国新记录种

报道了暗色丝孢菌的三个中国新记录种Beltraniella portoricensis、Spadicoides xylogena和Periconia circinata,其中Beltraniella和Spadicoides两属在中国首次发现.研究的标本保藏于山东农业大学植物病理标本室(HSAUP).     

A glimpse of lignicolous marine fungi occurring in coastal water bodies of Tamil Nadu (India)

In the present investigation, a total of 51 marine fungi were obtained from wood samples collected from four locations of Tamil Nadu (Tuthukudi, Chennai, Kanyakumari and Pichavaram), India. Out of these 51, 28 were ascomycetes, one was basidiomycete and 22 were mitosporic fungi. Maximum fungal diversity was encountered from Tuthukudi, followed by Chennai, Kanyakumari, and the minimum from Pichavaram. Periconia prolifica was the only species common to all the four locations.     

黄河三角洲地区土壤中暗色丝孢菌研究初报Ⅰ

采用土壤平板法和稀释法从山东黄河三角洲地区土壤中分离出40个暗色丝孢菌分离物,鉴定为13属23种。其中光滑端梗霉Acrophialophora levis、大棘黑团孢Periconia macrospinosa、大孢瓶梗霉Phialomyces macrosporus、粗糙短梗蠕孢Trichocladium asperum、螺旋毛束霉Trichurus spiralis和树头毛束霉Trichurus dendrocephalus等6种真菌为中国新记录种。所报道真菌种的干制培养物保存在山东农业大学植物病理学标本室(HSAUP)。     

蒜头果内生真菌次生代谢产物抑制人类致病菌活性的研究

蒜头果是我国特有的单种属稀有树种,为了进一步开发利用蒜头果树皮内生真菌的抗菌活性化合物,该研究对来自蒜头果的植物内生真菌(白黄笋顶孢霉、哈茨木霉、大棘黑团孢、枝状枝孢菌、斑污拟盘多毛孢、赭绿青霉、淡紫紫孢菌、朱黄青霉、Xenoacremonium recifei、Xylaria feejeensis)进行液体培养,10 d后回收培养液并用乙酸乙酯萃取获得初提物,采用抑菌圈法检测蒜头果内生真菌初提物抑菌活性,同时测定了最低抑菌浓度(MIC)。结果表明:白黄笋顶孢霉、大棘黑团孢、枝状枝孢菌、斑污拟盘多毛孢、赭绿青霉、淡紫紫孢菌均有抑菌活性,大棘黑团孢、斑污拟盘多毛孢、淡紫紫孢菌的初提物均对缓慢芽孢杆菌、无乳链球菌和藤黄微球菌有明显抗菌活性,最低抑菌浓度在1.562 5~6.25 mg·m L~(-1)之间。这说明蒜头果树皮内生真菌的次生代谢产物具有抗菌活性,各内生真菌次生代谢产物的抗菌效果不同。     

A comparative account of backwater and brackish water marine mycoflora of North Malabar (Kerala) India

The backwater system of Kerala is well known. In the present investigation, we have tried to explore the marine fungal diversity of selected backwater and brackish water habitats of the North Malabar region of Kerala, India. A total of 30 marine fungi were isolated, which include 19 Ascomycetes, 1 Basidiomycete, and 10 Mitosporic fungi. Periconia prolifica emerged as the most dominant one in terms of percent frequency of occurrence and percent relative abundance.     

粉质和胶质滇重楼的研究

正常的滇重楼地下茎为粉质,多糖含量２．５６％。因黑团孢霉和其它微生物寄生,致使地下茎转化为胶质,多糖含量５．４４％。ＰＦ和ＪＰ的动物体内试验表明均有显著的免疫增强作用。这些结果显示胶质地下茎的药用价值相同于粉质的,它们可等同药用。     

云南热带地区土壤中的暗色丝孢菌初查

从云南西双版纳及河口热带雨林、植物园、荒坡和农田中采集混合土壤样品30余份,采用稀释平板法和土壤颗粒法从中分离获得暗色丝孢菌分离物53个,经形态鉴定分属于29属37种。其中4个为中国新记录种：尼尔布洛孢Bloxamia nilagirica、不规头梗孢Cephaliophora irregularis、单梗粘孢Haplographium delicatum和不列颠黑团孢Periconia britannica,对它们进行了描述和必要的讨论。研究过的标本（干制培养物）及活菌种保存在山东农业大学植物病理学标本室（HSAUP）。     

滇重楼寄生菌的研究

从滇重楼(Paris polyphylla var.yunnanensis)地下茎中分离和鉴定出两种细菌——蜡状芽孢杆菌(Bacillus cereus)和产碱假单胞菌(Pseudomonas alcaligenes),以及三种真菌——黑团孢霉(Periconia sp.)、白色厚顶孢霉(Pachnocybe albida)和重楼索霉(Hormomyces paridiphilus)。对蜡状芽孢杆菌、产碱假单胞菌和重楼索霉进行了液体培养并测定了胞外多糖含量,结果表明重楼索霉可分泌大量胞外多糖,这可能是导致滇重楼地下茎胶质化和多糖含量增加的原因。     

Pathotoxin effects in sorghum are also produced by mercuric chloride treatment

Pathogenic isolates of Periconia circinata produce a host-specific toxin (PC-toxin) and cause a root and crown rot in susceptible genotypes of sorghum. Treatment with PC-toxin leads to selective development of disease symptoms and an increase in synthesis of a group of acidic, low molecular weight proteins only in susceptible genotypes. Treatment of sorghum seedlings or excised root tips with HgCl₂ resulted in responses indistinguishable from those produced by treatment with PC-toxin, but the effects were not genotype specific.     

吉林松辽平原暨西部草原湿地土壤中的暗色丝孢菌

从吉林松辽平原暨西部草原湿地不同生态环境中采集土壤样品42份,采用土壤平板法和稀释法,从中分离出116个暗色丝孢菌分离物,经鉴定分属于25属,46种。其中,倒卵平脐蠕孢Bipolaris obovoidea为新种;二色单格孢Monodictys bicolorata、刚毛黑团孢Periconia hispidula和草色串孢小四变型Torula herbarum f. quaternella为中国新记录种。研究过的标本（干制培养物）及活菌种保存在山东农业大学植物病理学标本室（HSAUP）,等模式标本（干制培养物）存放在中国科学院真菌标本室（HMAS）。     

Endophytic fungi from the root tubers of medicinal plant Stephania dielsiana and their antimicrobial activity

The adverse effects of chemical synthetic fungicides on agricultural fields and the environment are driving a need to search for safer and less environmentally harmful plant protectants to move toward more sustainable development of agriculture. The endophytic fungal community associated with the medicinal plant Stephania dielsiana, and its potential for providing antimicrobial secondary metabolites were investigated. A total of 26 isolates of endophytic fungi were obtained, and 21 isolates were identified and classified into eight different genera, including Briansuttonomyces, Glomerella, Pleosporales, Diaporthe, Phoma, Penicillium, Periconia and Colletotrichum, and the most frequent endophytic species obtained were Diaporthe phaseolorum, Penicillium sp., Periconia igniari and Colletotrichum sp. The ethyl acetate (EtOAc) extract of the endophytic fungus Diaporthe phaseolorum Stdif6 displayed the most significant antifungal activity against all tested phytopathogens, with EC₅₀ values ranging from 0.0138 to 0.3103 mg/mL. While the EtOAc extract of the endophytic fungus Penicillium sp. Stdif9 exhibited greater potential for antibacterial activity, with the minimum inhibitory concentration (MIC) values against seven bacteria ranging from 1.25 to 6 mg/mL. The remarkable antimicrobial activity of fungal endophytes suggests that fungal endophytes harbored inside the root tubers of S. dielsiana hold great promise as biocontrol agents against a broad spectrum of economically significant pathogens.     

Seasonal patterns of primary colonization by lignicolous marine fungi in Hong Kong

During a 14-month investigation of the seasonal pattern of primary colonization by lignicolous marine fungi in the coastal waters of Hong Kong, a pine block (Pinus massoniana Lamb.) was submerged each month at each of the five stations and recovered in the following month. Thirty-eight species of fungi were isolated, three of which were not identified. In this first recorded attempt to describe fungal colonization on submerged blocks quantitatively, five species (Periconia prolifica, Cirrenalia macrocephala, Ceriosporopsis halima, Trichocladium achrasporum and Halosphaeria quadricornuta) were the most frequent and most abundant fungi on the monthly blocks. Statistical analyses of seasonal abundance of these fungi are presented and their occurrence in relation to varying temperature and salinity throughout the year, including the Phoma pattern, are discussed.     

The Role of Marine Fungi in the Penetration of Calcareous Substances

All publications dealing with fungi described from marine calcareoussubstrates are discussed in this survey of the literature. Originalinvestigations of fungi from lime tubesof teredinids are included.Wood-inhabiting marine fungi, especially in warm waters, growwithin calcareous linings of teredinid burrows. Fruiting structuresof the Ascomycetes, Halosphaeria quadricornuta and Remisporasalina, and the Deuteromycete, Periconia prolifica, form cavitiesin the tube linings, making them brittle and soft. Representativesof Cirrenalia and Humicola sporulate on the surface of calcareouslinings. The fungus, Pharcidia balani, sometimes referred toas a lichen, decomposesshells of barnacles and molluscs. AnotherAscomycete, Lulworlhia kniepii, parasitizes calcareous algae,probably living on the middle lamellae, not on the calcifiedcell walls.     

Natural pericosines B and C as enantiomeric mixtures: direct evidence by chiral HPLC analysis

Pericosines are carbasugar-type metabolites of Periconia byssoides OUPS-N133, a fungus that was originally separated from the sea hare Aplysia kurodai. It has been reported that pericosines C and E are enantiomeric mixtures. The difference in specific rotation between natural pericosine C and the synthetic one led to the conclusion that natural pericosine C is an enantiomeric mixture. Meanwhile, the small specific rotation of natural pericosine B compared to that of the synthetic one led to the deduction that natural pericosine B might also be an enantiomeric mixture. Then, racemic pericosines B and C were synthesized, and the direct enantioseparation of these racemic carbasugars was conducted with CHIRALPAK? IA and CHIRALPAK? AY-H, which are suitable columns for racemic pericosines B and C, respectively. Using chiral HPLC, we conclude that natural pericosines B and C exist as enantiomeric mixtures. A rare example of the application of direct chiral HPLC analysis to intact sugars or carbasugars was provided.     

Differential synthesis of peritoxins and precursors by pathogenic strains of the fungus Periconia circinata.

Pathogenic strains of the soilborne fungus Periconia circinata produce peritoxins with host-selective toxicity against susceptible genotypes of sorghum. The peritoxins are low-molecular-weight, hybrid molecules consisting of a peptide and a chlorinated polyketide. Culture fluids from pathogenic, toxin-producing (Tox(+)) and nonpathogenic, non-toxin-producing (Tox(-)) strains were analyzed directly by gradient high-performance liquid chromatography (HPLC) with photodiode array detection and HPLC-mass spectrometry to detect intermediates and final products of the biosynthetic pathway. This approach allowed us to compare the metabolite profiles of Tox(+) and Tox(-) strains. Peritoxins A and B and the biologically inactive intermediates, N-3-(E-pentenyl)-glutaroyl-aspartate, circinatin, and 7-chlorocircinatin, were detected only in culture fluids of the Tox(+) strains. The latter two compounds were produced consistently by Tox(+) strains regardless of the amount of peritoxins produced under various culture conditions. In summary, none of the known peritoxin-related metabolites were detected in Tox(-) strains, which suggests that these strains may lack one or more functional genes required for peritoxin biosynthesis.     

Purification and characterization of a β-1,3-glucanase from the novel mycoparasite <Emphasis Type="Italic">Periconia byssoides</Emphasis>

An extracellular β-1,3-glucanase with antifungal properties was secreted by the novel mycoparasite, Periconia byssoides. The glucanase has a molecular mass of 35 kDa estimated by SDS-PAGE. Its optimum activity was at pH 6.0 and 50°C (over 2 h). The purified β-1,3-glucanase was capable of degrading cell walls, and inhibiting mycelia growth and spore germination of plant pathogenic fungi including Fulvia fulva, Fusarium sp. and Rhizoctonia solani. The N-terminal amino acid residues of the purified β-1,3-glucanase are LKNGGPSFGA, which do not have any homology with previously described glucanases, suggesting it may be a novel member of the fungal β-1,3-glucanases. Chao Lin and Jinkui Yang contributed equally to this work.     

Effects of host-specific toxins on electropotentials of plant cells

Host-specific toxins from Helminthosporium victoriae (HV) and Periconia circinata (PC) caused gradual decreases in the negative electropotentials of single cells of susceptible but not of resistant plants. When tissues were held in a standard nutrient solution, the decrease (depolarization) induced by HV toxin was approximately 50 mv/hr; the decrease induced by PC toxin was even more gradual. Changes in ion efflux were detected before changes in electropotential. In contrast, toxin from H. carbonum caused a rapid but transient increase in negative electropotential of cells. Carbonyl cyanide m-chlorophenylhydrazone, which (like other metabolic inhibitors) blocks electrogenic pumps, caused cell electropotentials to decrease by approximately 50 mv within a few minutes. This suggests that HV and PC toxins do not have direct effects on electrogenic pumps, but do affect passive efflux of ions, or electrically neutral ion exchange systems, across the plasma membrane.