Arthrographis kalrae soluble antigens present hemolytic and cytotoxic activities

Arthrographis kalrae is a dimorphic, cosmopolitan and neurotropic fungus that has been described as a rare human pathogen. This study investigated the hemolytic and cytotoxic activities of A. kalrae cell-free antigens (CFAs). Total CFAs and their Sephadex chromatography fractions were tested on mouse erythrocytes for hemolysis and on the P3U1 cell line for cytotoxicity. Hemolytic and cytotoxic activities were detected in distinct molecular mass (MM) fractions. Additionally, antibodies against isogenic erythrocytes sensitized with CFAs (anti-E-CFAs) inhibited hemolysis but not cytotoxicity. Hemolysis was not affected by heating, and a higher reactivity was detected in the carbohydrate-rich fractions, which decreased after reduction by periodate treatment. The pioneering nature of this work is due to the demonstration of the cytotoxic activity in A. kalrae and the suggestion that this activity may be due to molecules distinct from the hemolytic factor, with the latter potentially being a component with a high MM.     

Interactions between arbuscular mycorrhizal fungi and fungivorous nematodes on the growth and arsenic uptake of tobacco in arsenic-contaminated soils

The effects of inoculation with two AM fungi (M1, Glomus caledonium; M2, Glomus spp. and Acaulospora spp.) and a fungivorous nematode Aphelenchoides sp. on growth and arsenic (As) uptake of Nicotiana tabacum L. were investigated in soils contaminated with a range of As. The reproduction of Aphelenchoides sp. was triggered by the co-inoculation of AM fungi regardless of AM fungal isolates and As levels. Stimulative effects of Aphelenchoides sp. on the development of mycorrhiza, slightly different between two AM fungi, were found particularly at the lowest As level. Irrespective of mycorrhizal inoculi, increasing soil As level decreased plant growth, but increased plant As uptake. Co-inoculation of AM fungi and Aphelenchoides sp. led plants to achieving further growth and greater As accumulation at the lowest As level. Results showed that the interactions between AM fungi and fungivorous nematodes were important in plant As tolerance and phytoextraction at low level As-polluted soil.     

广州地区番石榴病害鉴定

根据近几年对广州地区番石榴病害调查,初步鉴定出番石榴病害13种;真菌病害12种,藻类病害1种。其中果实病害7种,叶斑类6种。果实上以炭疽病严重,其次为褐腐病。黑腐病(Botryodiplodia theobromae Pat.);褐腐病(phomopsis psidii de Camara);茎点霉果腐病(phoma psidii Ahmad);果褐点病(Cercospora psidii Rengel);褐污斑病(Mycovellosiella myrtacearum A.N.Rai et al );叶斑病(phyllosticta psidii.Tassi);叶枯病(phomopsis destructum D.P.C. Rao,Agrawal et Saksena);灰斑病(pestalotiopsis disseminatum (Thuem.)Stey.)8种病害系国内首次报道。3种病原为新种,将另文发表。本文最后讨论了有待于进一步研究的问题。     

真菌侵染对泡桐材微观结构及主要组分的影响

进行了变色真菌对泡桐木材微观构造及主要组分的影响研究,作了链格孢菌（Alternaria alternata)侵染泡桐木材试验,检测了真菌对泡桐木材的侵染状况,并确定了真菌侵蚀泡桐木材的主要部位,测试了泡桐木材在真菌作用下的成分变化,阐明了真菌导致泡桐木材发生变色的物理化学过程。     

霉变玉米分离真菌YMF-7产物中毒素成分的识别

[目的]研究霉变玉米分离的真菌YMF-7代谢产物中的毒性成分。[方法]利用海虾毒性指标,采用Sephadex LH-20、硅胶和HPLC等柱色谱技术对YMF-7毒性菌株发酵物进行毒性追踪分离。[结果]共分离得到2个化合物,结构鉴定为化合物1为Gliotoxin(6),化合物2为Gliocladin(7)。经海虾毒性测定,结果表明,化合物1对海虾的LC50值为0.34μg/ml,化合物2对海虾的LC50值为2.10μg/ml。[结论]该2种化合物为YMF-7发酵物中的主要毒性成分。     

桑枝食用菌对1-脱氧野尻霉素的富集作用

[目的]探讨食用菌对桑枝中1-脱氧野尻霉素（1-deoxynojimycin,DNJ）的富集作用。[方法]利用反相高效液相色谱法,研究耳菇、香菇、金针菇、鸡腿菇、银耳、姬菇、黑木耳、灵芝、猴头菇9种食用菌对桑枝中1-脱氧野尻霉素（1-deoxyno jimycin,DNJ）的富集能力。[结果]供试食用菌种均不能自我合成DNJ,但黑木耳、灵芝和猴头菇对DNJ有富集作用,而且其菌盖的富集能力远远高于菌柄。随着培养料中桑枝屑比例的增加,灵芝和猴头菇菌盖中DNJ含量也随之增加,在50%桑枝屑时达到最大,分别为0.0704%和0.0472%,再增加桑枝屑比例,则其菌盖中DNJ含量下降,当桑枝屑比例为80%时,其菌盖中DNJ含量分别降为0.0474%和0.0327%。[结论]该研究可为开发具有降血糖功效的桑枝食用菌提供理论依据和参考。     

泡桐材变色类型的确定及变色真菌的鉴定

对泡桐材变色类型的研究表明,泡桐材变色存在着真菌变色。同时从新伐的泡桐木材中分离出两种真菌,经鉴定是链格孢菌和一种根霉菌,这两种真菌可引发泡桐木材变色。     

沙漠人工种植芨芨草对土壤微生物数量的影响

通过测定对照(自然状态)与芨芨草地土壤放线菌、细菌和真菌的数量变化,分析了沙漠人工种植芨芨草对土壤微生物的影响。结果表明:对照与芨芨草地土壤中均以放线菌数量最多,细菌次之,真菌数量最少。从微生物总数及各类群微生物数量分别来看,芨芨草地均明显高于对照土壤。芨芨草地土壤中放线菌、细菌和真菌均集中分布在土壤的0~10 cm土层范围内,特别是0~5 cm土层。沙漠人工种植芨芨草对于促进土壤微生物生长,改善土壤有显著作用。     

超声辅助提取丝状真菌被孢霉中油脂的工艺研究

通过超声波辅助提取丝状真菌被孢霉中油脂的研究试验,确定影响提取的4个主要因素(超声波功率、提取温度、超声时间、料液比),以及丝状真菌被孢霉中油脂的超声波辅助提取的最佳萃取工艺。结果表明,超声波功率为120W,提取温度为45℃,超声时间为40min,料液比为1∶9,油脂平均得率为43.67%。     

污染马铃薯试管苗真菌的分离鉴定

用马铃薯葡萄糖琼脂(PDA)培养基和VBC培养基、麦粒培养基及查氏培养基等选择性培养基对宁夏5个马铃薯脱毒中心的污染马铃薯试管苗真菌进行分离培养,经形态学鉴定,这些真菌分属6属至少12种,其中镰刀菌属有5个种,其次是毛霉属有2个种,第三是链格孢属有2个种,根霉属最少,镰刀菌属真菌分离出的比率最高.比较宁夏5个马铃薯脱毒中心真菌分离株数,以海原县马铃薯脱毒中心真菌分离株数远高于其他马铃薯脱毒中心,其他马铃薯脱毒中心差异不明显.