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Extraction of Dictyonema glabratum with hot 2% (w/v) aqueous KOH at 100 degrees C, followed by neutralisation and freeze-thawing, gave an insoluble glucan. The residue was further extracted by a similar process, but with hot 10% (w/v) aqueous KOH, furnishing a mixture of glucan, mannan and xylan. The mannan and xylan were obtained via precipitation of its copper complex with Fehling's solution, leaving the glucan in the supernatant. The insoluble complex was finally purified through gel permeation chromatography. Methylation analysis, one- and two-dimensional nuclear magnetic resonance examination showed the polysaccharides to be a (1-->3)-linked alpha-glucan (pseudonigeran) and a (1-->4)-linked beta-xylan, both not previously encountered in lichens, and a newly discovered (1-->6)-linked beta-mannan.  相似文献   
13.
Two new cyclopeptides simplicilliumtides N and O (1 and 2) along with three known analogues verlamelins A, B and simplicilliumtide J (3-5) were isolated from the deep-sea-derived fungal strain Simplicillium obclavatum EIODSF 020 by bioassay-guided isolation method. Their structures of 1 and 2 were elucidated by spectroscopic analysis, and their amino acid configurations were determined by Marfey’s method. All isolated compounds showed significant antifungal activity against two phytopathogenic fungi Alternaria solani and Colletotricum asianum with MIC values of 0.195–6.250 μg/disc. This study suggests the fungal strain S. obclavatum EIODSF 020 is a new source for developing natural fungicides.  相似文献   
14.
Abstract Using fungi grown on synthetic agar medium, we evaluated and compared the concentration of various H2O2-producing enzymes. Our results showed that oxidase production in solid medium was better than that found in liquid medium and as high as that detected in wood samples. High yields of oxidases made it possible to compare different oxidases in the same culture extracts and under different conditions. Our results also indicated that H2O2 production is ubiquitous in the white rot fungi tested and that enzyme levels are influenced by the substrate composition.  相似文献   
15.
威海地区547例甲真菌病真菌培养结果分析   总被引:2,自引:3,他引:2  
目的了解山东省威海地区甲真菌病的临床分类、菌种构成等流行情况。方法对547例镜检阳性的甲真菌病患者进行真菌培养、鉴定和临床分析。结果547例患者中真菌培养阳性423例,阳性率77.3%,远端侧位甲下型甲真菌病(DLSO)295例(53.9%),白色浅表型甲真菌病(SWO)36例(6.5%),近端侧位甲下型甲真菌病(PSO)78例(14.2%),全甲营养不良型甲真菌病(TDO)138例(25.2%)。共分离出429株真菌,其中皮肤癣菌354株(82.5%),酵母菌61株(14.2%),非皮肤癣菌霉菌14株(3.3%)。结论山东省威海地区甲真菌病病原体的分布以皮肤癣菌为主,其次为酵母菌和非皮肤癣菌霉菌,红色毛癣菌是最常见的皮肤癣菌,临床类型以DLSO型居多,其他依次是TDO、PSO、SWO。就诊人群中以20~50岁年龄段为最多见。  相似文献   
16.
A smut fungus onPrimula sieboldii was newly found in Japan and identified asUrocystis tranzscheliana by comparative morphology. This species causes systemic infection ofP. sieboldii and produces sori in its ovaries.Contribution No. 121, Laboratories of Plant Pathology and Mycology, Institute of Agriculture and Forestry, University of Tsukuba.  相似文献   
17.
报道了中国疱衣科疱衣属一新记录种:类喜马拉雅疱衣(Phlyctis subhimalayensis S. Joshi&Upreti),提供了该种的形态特征描述和DNA数据支撑。还对中国已知的疱衣属物种进行了简要描述。同时讨论了近似种,编制了分种检索表,为疱衣属的进一步研究提供了基础资料。  相似文献   
18.
Two thermostable enzymes produced by the thermophilic fungus Paecilomyces varioti, a chitinase and laminarinase, were used to isolate protoplasts of a thermophilic fungus, Malbranchea sulfurea. The frequency of protoplast regeneration observed (35%) was considerably higher than that obtained using commercial lytic enzymes.  相似文献   
19.
The white rot fungus Phanerochaete chrysosporium, which generally mineralizes substituted aromatics to CO2, transformed linear alkylbenzene sulfonate (LAS) surfactants mainly at their alkyl side chain. Degradation of LAS was evidenced by a zone of clearing on LAS-containing agar plates and colorimetric analysis of liquid cultures. Disappearance of LAS was virtually complete within 10 days in low nitrogen (2.4 mM N), high nitrogen (24 mM N) and malt extract (ME) liquid media. After 5 days of incubation in ME medium, transformation of LAS was complete at concentrations4 mg l-1, but decreased at higher concentrations. The LAS degradation was not dependent on lignin peroxidases (LiPs) and manganese-dependent peroxidases (MnPs). Mineralization of14C-ring-LAS to 14CO2 by P. chrysosporium was <1% regardless of the culture conditions used. Thin layer chromatography and mass spectral analyses indicated that P. chrysosporium transformed LAS to sulfophenyl carboxylates (SPCs) through oxidative shortening of the alkyl side-chains. While LAS disappearance in the cultures was not dependent on LiPs and MnPs, transformation of the parent LAS moieties to SPCs was more extensive in low N medium that favors expression of these enzymes. The SPCs produced in LN cultures were shorter in chain-length than those produced in ME cultures. Also there was a notable shift in the relative abundance of odd and even chain length metabolites compared to the starting LAS particularly in the low N cultures suggesting the possible involvement of processes other than or in addition to-oxidation in the chain-shortening process.  相似文献   
20.
An endogenous filariform fungus has been separated from a tree named Taxus growing in the Aba region, Sichuan, China. The fungus is fermented in fluid medium for 3 weeks at 25℃, then the HPLC and MALDI-TOF analysis of the zymotic fluid show that the zymotic fluid contains taxol. So it is a fungus which can produce taxol. It is named Taxomyces sp. temporarily.  相似文献   
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