Distribution of acetyl esterase in wood-rotting fungi

The distribution of acetyl esterase was studied in 30 strains of wood-rotting fungi. A screening test on agar plates using glucose β-d-pentaacetate as a substrate indicated that all tested fungi produced acetyl esterase to form a clear zone on the culture. All fungi also showed positive responses in an agar test using carboxymethyl cellulose acetate. Enzyme assay showed that extracellular acetylxylan esterase activity was present in the filtrates of wood-meal culture of all these fungi. The ratio of fungal acetylxylan esterase activity to 4-nitrophenyl acetyl esterase activity were higher than that of porcine liver esterase, indicating that fungal esterases have high affinity for acetylated carbohydrates. Acetyl esterase is suggested to be distributed widely in wood-rotting fungi for degradation of native acetylated hemicelluloses.     

干皮孔菌属的一个新种和三个组合种

本文报道了产自斯里兰卡的干皮孔菌属一个新种,该种的主要特征是具有平伏反卷或具菌盖的子实体,很小的孔口（每毫米8-10个）,菌丝系统二系,生殖菌丝覆盖有刺状结晶,骨架菌丝橙棕色,细腊肠状担孢子（2.7-3.4×0.5-0.8μm）。基于ITS和nLSU序列的系统发育分析表明该新种属于干皮孔菌属的一个明确的分支。此外,将毛孔菌属组合到干皮孔菌属中,并报道了3个组合种,白边干皮孔菌、印度干皮孔菌和萨彦干皮孔菌。     

The effect of copper on the growth of wood-rotting fungi and a blue-stain fungus

The effect of copper (II) ions on the growth of three brown-rot fungi, six white-rot fungi and one blue-stain fungus in solid medium was evaluated. The fungi were grown in malt extract agar with different concentrations of copper added, and the radial growth rate was determined. At the end of the incubation period, the mycelial biomass and the media pH were determined. The white-rot and blue-stain fungus grew up to 3 mM and 6 mM copper, respectively and the brown-rot fungi were the only ones that grew up to 10 mM, with higher growth rates than those shown by the other fungi. In general, the brown-rot fungi produced greater acidification in the culture media than the white-rot fungi and blue-stain fungus, and the acidification increased when the amount of copper was increased. The biomass production for the different species, in the absence or presence of copper, was not related to the radial growth rate, and the fungal species that produced the greatest biomass amounts did not correspond to those that presented the highest growth rates. The brown-rot fungi Wolfiporia cocos and Laetiporus sulfureus and blue-stain fungus Ophiostoma sp. demonstrated greater tolerance to high copper concentrations in solid medium than the white-rot fungi, determined as radial growth rate. On the other hand, the highest biomass producers in solid medium with copper added were the white-rot fungi Ganoderma australe and Trametes versicolor and the brown-rot fungus Gloeophyllum trabeum.     

Immobilization of wood-rotting fungi laccases on modified cellulose and acrylic carriers

Extracellular laccases produced by three different wood-rotting fungi, Cerrena unicolor, Heterobasidion annosum and Trametes versicolor, were immobilized via covalent bonds formation on DEAE-Granocel 500, CM-Granocel 500, and acrylic carriers. Out of the tested carriers, only the DEAE-Granocel 500, which was activated by divinyl sulphone appeared to be a suitable matrix for the expression of enzymic activity. Only one laccase of all the tested enzymes produced by C. unicolor showed the best binding to the carrier and a satisfactory enzymic activity. The immobilized laccase exhibited the highest enzymic activity at pH 5.2 and it was more resistant to thermal denaturation than the native enzyme. At 90 °C, it retained 75% activity compared to the free enzyme. It was also more stable during storage at 4 °C: after 4 months the immobilized laccase retained 98% of initial activity. Immobilized C. unicolor laccase was active in 10–60% concentration of methanol, acetone, isopropanol or acetonitrile. The best enzymic activity was observed in 20% solution of acetonitrile in buffer.     

体内和体外评价法分析内生真菌粗提取物的抗氧化活性

对几株经初筛具较高抗氧化活性的疏花水柏枝的内生真菌展开研究,在体内和体外两种方法下分析了其抗氧化能力。本研究选择1,1-二苯基-2-三硝基苯肼(DPPH)法、总抗氧化能力(T-AOC)试剂盒和铁氰化钾还原力测定法来评价内生真菌的体外抗氧化活性,并对不同方法进行了比较分析;建立并优化了大肠杆菌的氧化损伤模型,并将内生真菌对其保护作用与对人神经母瘤细胞SH-SY5Y的氧化损伤保护作用进行比较,分析了不同内生真菌在体内的抗氧化活性。结果表明体内和体外的抗氧化分析方法存在一定偏差,体外分析中活性最高的菌株是SJ-12和QY-1,体内分析中对大肠杆菌抗氧化保护效果最好的菌株也是QY-1和SJ-12,但对神经细胞保护效果最好的菌株是QY-1和MG-9。综合几种方法,本实验证明了内生真菌QY-1及其发酵产物具较强的抗氧化活性,可以作为潜在的新型抗氧化剂开发利用。     

Effect of carbon levels from three organic substrates on egyptian soil fungi

Summary The fungal composition of soils with an equivalent percentage of carbon levels 2%, 5%, 10% and 20% fromOlea europea,, Citrus sinensis andEucalyptus rostrato leaves was studied after 10, 45 and 120 days using the dilution-plate method. They all induced significant increases in the total count of fungi, but their effect on the individual fungi was selective. The best substrate for the total fungus flora wasCitrus sinensis and the poorest wasOlea europeae leaves. The best three colonisers (possessing the highest counts), at carbon levels 2%, 5%, 10% and 20% at the end of the experimental periods were, respectively, as follows: forOlea europeae leaves,Scopulariaopsis brevicaulis, Drechslera halodes andCylindrocarpon sp.;Aspergillus quadrilineatus, A. sydowi andCurvularia lunata; A. quadrilineatus, Alternaria alternata andC. lunata andA. quadrilineatus, A. egyptiacus andA. terreus; forCitrus sinensis leaves,A. quadrilineatus, A. fumigatus andS. brumptii; A. fumigatus, A. quadrilineatus andA. versicolor; A. quadrilineatus, A. terreus andS. brumptii; andA. quadrilineatus, A. flavus andA. sydowi; and forEucalyptus rostrata leaves,A. quadrilineatus, Rhizopus stolonifer andA. sydowi; A. quadrilineatus, A. niger andA. terreus; A. niger, A. quadrilineatus andS. brevicaulis; andA. terreus, A. niger andA. quadrilineatus.     

Effects of fungivory by two specialist ciid beetles (Octotemnus glabriculus and Cis boleti) on the reproductive fitness of their host fungus, Coriolus versicolor

On the basis of the evidence that insect fungivory has the potential to affect fungal reproductive fitness, we investigated the effects of two specialist ciid beetles ( Octotemnus glabriculus and Cis boleti ) on the reproductive potential of their host fungus, Coriolus versicolor . We found, from field data, a negative correlation between the number of individuals of O. glabriculus inhabiting C. versicolor fruit bodies and the percentage of the fungal spore-producing surface (hymenium) that was functional. By contrast, the number of C. boleti inhabiting C. versicolor fruit bodies did not correlate with the percentage of functional hymenium. Experimentally, O. glabriculus and C. boleti reduced the reproductive potential of C. versicolor by 58% and 30%, respectively, whereas the combined trophic activity of both beetles caused a reduction of 64%. This latter effect was not significantly different from that caused by O. glabriculus alone. These findings disagree with previous assertions that insect fungivory on fruit bodies has only neutral effects on fungal fitness. We conclude that in the short-term, fungivory by ciids significantly decreases the area of functional hymenium of C. versicolor and is likely to reduce fungal reproductive fitness. Within this perspective the evolution of certain fungal characteristics (i.e. chemical composition, consistency and phenology) can be interpreted as being driven by fungivory.     

Indirect effects of a non-target species, Pyrrhalta luteola (Chrysomelidae) on the biodeterioration of Brussels tapestries

Treatments to preserve artwork are usually designed to control for known target species. Nevertheless, indirect effects of non-target species may cause important biodeterioration. During the restoration of a series of Brussels tapestries preserved in the Abbey of Sacromonte (Granada, Spain), we studied one of the tapestries which presented a high degree of deterioration, principally large losses of material and color alterations. We found important biodeterioration effects produced by a non-target insect species, the beetle Pyrrhalta luteola (Chrysomelidae). We raised P. luteola beetles in the laboratory on different constituent materials to identify the effects of this insect on the tapestry. Results showed that beetle remains were mainly responsible for the chromatic changes. Although beetles did not consume textile materials, and had not direct effects in tapestry destruction, its presence indirectly affected the tapestry due to the higher mold-growth obtained in samples of materials with beetle remains. Based on these results, we propose some recommendations to consider control for these potential biodeterioration agents in artwork conservation programs.     

Effect of arbuscular mycorrhizal fungi on phytoextraction by corn (Zea mays) of lead-contaminated soil

The role of arbuscular mycorrhizal fungi (AMF) in lead (Pb) uptake by corn (Zea mays) grown in soil supplemented with Pb was examined. Plants were subjected to four Pb levels: 0 (control); 10 (low); 100 (medium); and 500 mg L(-1) (high). At each Pb level, plants were grown in soil without and with fungicide (benomyl) (20 mg kg(-1)) to suppress AMF activity. Benomyl significantly reduced AMF colonization at high. medium, and zero Pb exposures. Benomyl application resulted in significantly lower concentrations of phosphorus in leaves at low and medium Pb exposures. The benomyl-treated plants had higher Pb and manganese concentrations in leaves than plants not treated with benomyl. In addition, benomyl-treated plants had generally lower concentrations of zinc and copper in leaves than plants not treated with benomyl. These results suggest that the role of AMF in heavy metal uptake is metal specific. Based on this work, the use of benomyl on soils contaminated with Pb can be recommended in phytoextraction.     

三种进境林木检疫性有害真菌名称的更正

2007年中华人民共和国农业部公布的《中华人民共和国进境植物检疫性有害生物》中包括了3种木材腐朽病原真菌,即松干基褐腐病菌Inonotus weirii (Murrill) Kotlaba et Pouzar、木层孔褐根腐病菌Phellinus noxius (Corner) G.H. Cunn.和橡胶白根病菌Rigidoporus lignosus (Klotzsch) Imaz.。基于国内外最新分子系统学研究,上述3种名称均发生了较大变化,为了适应进境林木检疫的需要及为今后植物检疫性有害生物名录的更新做好技术储备,我们对这3种重要的对外检疫性林木病原菌的名称说明和更改如下：松干基褐腐病菌Inonotus weirii (Murrill) Kotlaba et Pouzar的拉丁学名应改为Coniferiporia weirii (Murrill) L.W. Zhou & Y.C. Dai,相应的汉语学名也应改为韦氏松柏卧孔菌;木层孔褐根腐病菌Phellinus noxius (Corner) G.H. Cunn.的拉丁学名应改为Pyrrhoderma noxium (Corner) L.W. Zhou & Y.C. Dai,相应的汉语学名也应改为有害红皮孔菌;橡胶白根病菌Rigidoporus lignosus (Klotzsch) Imaz.是小孔硬孔菌Rigidoporus microporus (Sw.) Overeem的同物异名,因此其名称应叫做小孔硬孔菌Rigidoporus microporus (Sw.) Overeem。另外,有害红皮孔菌 Pyrrhoderma noxium和小孔硬孔菌Rigidoporus microporus已经在我国广泛分布,因此今后在修订进境植物检疫性有害生物名录时对有关有害生物种类进行增删应予以考虑。     

三种白腐真菌脱色噻嗪染料亚甲基蓝

本研究通过含亚甲基蓝染料的固体培养基,从19株白腐真菌菌株中分离获得3个脱色能力较强的菌株,其在平板上的脱色圈大小分别为7.5cm、6.8cm和5.5cm。鉴定其为：云芝栓孔菌Trametes versicolor（ZT-197）,绒毛栓孔菌Trametes pubescens（ZT-230）和亚黑管孔菌Bjerkandera fumosa（ZT-307）。其中,ZT-230对染料亚甲基蓝的脱色能力最强,可以将染料浓度为50mg/L的100mL液体培养基在6d之内100%脱色,而ZT-197和ZT-307在接种第10天时的脱色率为98%和80%。同时测定了3株白腐真菌在降解染料过程中的漆酶、锰过氧化物酶和木素过氧化物酶3种酶活力的规律：ZT-197和ZT-230均可分泌Lac和MnP两种酶,ZT-307只分泌LiP。本研究说明绒毛栓孔菌ZT-197在印染废水治理方面具有较好的应用前景。     

Antifungal activity of some plant extracts on some pathogenic fungi

The inhibitory activity of five plant extracts viz. Artemisia absinthium L., Rumex obtusifolius L., Taraxacum officinale Weber ex Wiggers, Plantago lanceolata L. and Malva sylvestris L. were evaluated against the mycelial growth of three fungi Alternaria alternata (Fr.) Keissler, Penicillium expansum Link ex Thom. and Mucor piriformis Fisher that cause rot diseases in fruits and vegetables resulting in low yield and quality of fruits and vegetables. Results revealed that all the concentrations of plant extracts brought about significant inhibition in the mycelial growth of these pathogenic fungi. However, the highest concentration caused maximum inhibition in the mycelial growth followed by lower concentrations of plant extracts. The extract of A. absinthium leaves at highest concentration (S) proved highly effective in inhibiting the mycelial growth of all these pathogenic fungi followed by other plant extracts. These plants thus may have potential as the new natural fungicide for management of fungal rot diseases.     

Elimination and detoxification of softwood extractives by white-rot fungi

The ability of several white-rot fungal strains to remove and detoxify acetone extractives (pitch or resin) in Scots pine sapwood was investigated in stationary laboratory batch assays. Fungal pretreatment provided up to 62% total pitch reduction and significant decreases in pitch toxicity. The best strains were Bjerkandera sp. strain BOS55, Stereum hirsutum and Trametes versicolor that eliminated over 93% of the problematic triglyceride fraction and 58–87% of other lipophilic extractive classes in only 2 weeks. Fungal removal of the wood extractives was accompanied by a 7.4–16.9-fold decrease in their inhibitory effect, as determined in the Microtox bioassay. Wood pretreatment by Bjerkandera sp. and T. versicolor caused limited losses of woody mass (less than 4% in 4 weeks); whereas S. hirsutum led to somewhat higher mass losses (7% in 4 weeks). These results indicate the potential of white rot fungi to control pitch deposition problems in pulping and to reduce the aquatic toxicity caused by naturally-occurring lipophilic extractives in forest industry effluents.     

丛枝菌根真菌对不同番茄品种抗根结线虫病的影响

【背景】根结线虫病害严重制约我国设施蔬菜的生产。丛枝菌根真菌(Arbuscular Mycorrhizal Fungi,AMF)作为土壤中最重要的有益真菌之一,可以促进植物生长,提高植物抗病性,减轻土传真菌和线虫病害的发生。在蔬菜保护地栽培中,AMF对于植物线虫病防治作用的研究受到了广泛关注。【目的】针对番茄生产中危害最严重的南方根结线虫(Meliodogyne incognita)病害问题,研究AMF和番茄品种不同组合的抗线虫效应,以期为菌根真菌作为生物防治剂和生物菌肥应用于实际生产提供技术基础。【方法】在灭菌土壤中,人工接种根结线虫,比较不同菌种Rhizophagus intraradices(Ri)、Acaulosporamellea(Am)及菌种组合Rhizophagusintraradices+Acaulosporamellea(Ri+Am)在不同番茄品种(感病品种蒙特卡罗和抗线虫品种仙客1号)上对南方根结线虫侵染和繁殖的影响,研究AMF对根结线虫的拮抗效应。另外,采用南方根结线虫连作发病的土壤,在感病品种蒙特卡洛上接种AMF混合菌种Ri+Am,番茄苗移栽入连作土壤中,测定各生长指标和调查根结和卵块数量,评价接种AMF处理对根结线虫病的防治效果。【结果】在灭菌土壤中,普通番茄品种蒙特卡罗的菌根效应显著优于抗线虫番茄品种仙客1号,表现为前者单位根重的根结和卵块的数量均比对照显著降低,而后者仅降低了卵块数量;蒙特卡罗上接种Ri+Am混合菌种的效果优于接种单一菌种Am和Ri;而仙客1号上接种Ri的效果更好。接种线虫也显著影响了AMF的侵染,而且对抗性品种仙客1号的影响更为明显。但除了接种Am的处理,大多数处理收获时菌根侵染率仍维持较高的水平(70%以上)。在连作土壤中,感病品种蒙特卡罗接种混合菌种Ri+Am具有较好的抗/耐线虫效应,主要表现为促进植株生长,显著降低根结和卵块数量,但菌根侵染率较灭菌土壤低,约为40%。【结论】综合以上结果,表明菌根化苗能够在一定程度上减轻根结线虫病的危害。土壤灭菌条件下,在感病和抗线虫番茄品种上接种AMF能够减轻线虫的侵染和繁殖,而且在感病品种上的防治效果更加显著。在连作土壤中,在番茄感病品种上接种AMF也表现较好的抗线虫效果。     

Detection of poly(ADP ribose) polymerase in crude extracts by activity-blot.

We have recently devised an activity-blot procedure permitting the detection, on the same nitrocellulose sheet, of the functional poly(ADP ribose) polymerase (PARP) activity as well as the immunostained active peptide(s) after renaturation of the transferred protein(s). Using this technique we have analyzed the PARP activity in higher and lower eukaryotes directly on crude extracts from cell cultures. This procedure has been extended also to in situ screening of bacterial colonies expressing the PARP enzymatic activity.     

A new genus and species of timber beetle (Coleoptera: Lymexylidae) from the Baltic amber

Ponomarenkylon alexandri gen. et sp. nov. (Melittommatinae) from the Late Eocene Baltic amber is described. The long filiform antennae and the apparent absence of sensillary organs, which are frequently present on modified maxillary palps in other lymexylids, are evidence of the primitive state of the new genus.     

不同碳源对三种溶磷真菌溶解磷矿粉能力的影响

通过液体培养法 ,对 3种溶磷真菌利用葡萄糖、果糖、蔗糖、麦芽糖、淀粉和纤维素等碳源溶解宜昌产磷矿粉的试验 ,结果表明 ,菌株P2 3在供给葡萄糖时的溶磷能力最高 ,并在一定程度上能够利用长链碳源淀粉和纤维素为营养而溶磷 ;而高效溶磷菌株P6 6和P39溶磷的最佳碳源是果糖和麦芽糖 ,该两菌株利用淀粉和纤维素的溶磷效果很小 ,甚至不溶磷。 3种溶磷真菌培养滤液 pH值、可滴定酸含量与其溶磷量之间的相关性因菌株而异 ,差别很大。菌株P2 3培养滤液pH值、可滴定酸含量与其溶磷量之间相关性很低 ,但菌株P6 6和P39培养滤液pH值、可滴定酸含量与其溶磷量之间相关性却达到极显著水平 (P <0 0 1)。结果表明 ,不同碳源对溶磷菌溶解磷矿粉能力影响很大 ,分析推断 3种菌株产生的有机酸活化磷矿粉能力为P6 6>P39>P2 3。     

Effect of physical, chemical and environmental characteristics on arbuscular mycorrhizal fungi in Brachiaria decumbens (Stapf) pastures

Aim:  To evaluate the effects of soil physical and chemical factors (pH, conductivity, humidity, available phosphorus and organic matter) and environmental factors (temperature, relative air humidity, altitude and atmospheric pressure) on arbuscular mycorrhizal fungi (AMF)– Brachiaria decumbens grass relationship. Furthermore to establish patterns of microbiological responses that allow to differentiate the study sites in two relief types.
Methods and Results:  Mycorrhizal characteristics (spore density, external hyphae and root colonizations by hyphae, vesicles and arbuscules), physical and chemical factors in soil and environmental factors were measured.
Conclusions:  The effect of physical, chemical and environmental factors on microbiological variables was related to the type of relief 'valley and hilly terrain'; the AMF behaviour was affected only over narrower ranges of evaluated variables. Similarly, the colonization of B. decumbens roots by AMF hyphae, vesicles and the mycorrhizal spore density follow different patterns according to the relief type.
Significance and Impact of the Study:  The type of relief is one of the factors to be taken into consideration to evaluate the AMF inoculum and root colonization of these pastures, because of the influence of slope – as physical property of soil – on AMF.     

Effect of enzyme extracts isolated from white-rot fungi on chemical composition and in vitro digestibility of wheat straw

A series of in vitro experiments were completed to evaluate the potential of enzyme extracts, obtained from the white-rot fungi Trametes versicolor (TV1, TV2), Bjerkandera adusta (BA) and Fomes fomentarius (FF), to increase degradation of cell wall components of wheat straw. The studies were conducted as a completely randomized design and analysed using one-way ANOVA. Enzyme activities of the extracts, previously obtained from a liquid culture medium, were characterized in terms of laccase and peroxidase for ligninolytic activity. Carboxymethyl cellulase (CMCase) and avicell digesting cellulase (Avicelase) were used for cellulolytic enzyme assays. Wheat straw samples were incubated with enzyme extracts in a citrate buffer (pH 5.0) in a forced air oven at 25 °C for 6 days. In vitro NDF digestibility (IVNDFD), and the rate and extent of NDF fermentation, without and after incubation with the white-rot enzyme extracts, were determined using a gravimetric microbiological method and a gas production technique, respectively. Results from cell wall chemical composition showed that TV2 and BA enzyme extracts decreased NDF concentration (P<0.05) and that TV1 had higher activity (P<0.05) towards cellulose. There was an increase in IVNDFD (P<0.05), resulting from treatment of wheat straw with enzyme extracts from BA, TV1 and TV2, reaching a difference of 13% for TV2 (P<0.05), versus the non-treated straw control. Treatment with enzyme extract from TV2 caused increased gas production (P<0.05) after the first 20 h of incubation, and also increased the maximum rate of gas production, thus enhancing fermentation kinetics. This study indicates that enzyme extracts from white-rot fungi can be used to develop new approaches to overcome low digestibility of some plant cell walls. Utilization of different substrates to produce enzyme extracts can lead to production of viable ligninolytic complexes which could improve the nutritive value of fibrous feeds.