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81.
Freshwater lichens of selected Carpathian streams were investigated to identify their diversity and distribution patterns. Lichens were investigated along six transects, each running across three different habitats (hydrological zones: submerged, splash and riparian), established in upper, middle and lower reaches of the streams and the data were a subject to statistical analyses. The studied mountain streams provided suitable habitats for a number of aquatic and semi-aquatic lichens and species richness in both streams was very similar. Overall, 52 species of lichens were identified from all sampling plots (γ diversity). Species number for a single plot (α diversity) ranged from 1 to 14 species and differences in species composition between the plots (β diversity) were high. Differences were mainly noted for typical terrestrial lichens occurring in riparian zones. The location along the stream reaches did not have a significant effect on species diversity and distribution. The hydrological zone appeared to be the most important predictor explaining the small-scale occurrence and diversity of lichens with species assembled into distinct, low-diversity communities in the transition from submerged to riparian habitats. The distinction among hydrological zones and their lichen biota were corroborated by nMDS analyses. The method of defined plots provides a way of recording baseline data for a particular river, which can be repeated (monitor) in the future.  相似文献   
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83.
刘慧  杨振男  刘岚  陈碧双 《海洋科学》2018,42(3):106-112
研究了海洋真菌介导邻-、间-、对-溴苯乙酮的不对称还原反应。具体考察了Rhodotorulamucilageinosa GIM 2.157对邻-、间-、对-溴苯乙酮的催化活性和对映选择性,并综合考察了反应温度、pH、反应时间和底物浓度等因素对还原产物的产率及立体选择性的影响。确定最佳反应条件:反应温度为25℃,反应体系的pH为7,反应时间为24 h,底物浓度为10 mmol/L。在最佳条件下,产率以及立体选择性均99%。  相似文献   
84.
Eight marine-derived fungi that were previously selected for their abilities to decolorize RBBR dye were subjected to pyrene and benzo[a]pyrene degradation. The fungus Aspergillus sclerotiorum CBMAI 849 showed the best performance with regard to pyrene (99.7%) and benzo[a]pyrene (76.6%) depletion after 8 and 16 days, respectively. Substantial amounts of benzo[a]pyrene (>50.0%) depletion were also achieved by Mucor racemosus CBMAI 847. Therefore, these two fungal strains were subjected to metabolism evaluation using the HPLC-DAD-MS technique. The results showed that A. sclerotiorum CBMAI 849 and M. racemosus CBMAI 847 were able to metabolize pyrene to the corresponding pyrenylsulfate and were able to metabolize benzo[a]pyrene to benzo[a]pyrenylsulfate, suggesting that the mechanism of hydroxylation is mediated by a cytochrome P-450 monooxygenase, followed by conjugation with sulfate ions. Because these fungi were adapted to the marine environment, the strains that were used in the present study are considered to be attractive targets for the bioremediation of saline environments, such as ocean and marine sediments that are contaminated by PAHs.  相似文献   
85.
以7种水产病原菌为指示菌,采用菌饼法对分离自南麂岛海域的15个沉积物样品中的78株海洋真菌进行抑菌活性初筛,获得了对至少一种病原指示菌有抑菌活性的菌株19株.采用打孔扩散法对这19株真菌的发酵液进行抑菌活性复筛,共有9个菌株的次级代谢产物对一种或者几种病原指示菌有抑制作用,其中菌株NJ0104的次级代谢产物对除灿烂弧菌...  相似文献   
86.
对红树林植物的枝干、枝叶样品进行微生物分离,以P388细胞为模型进行活性评价得到14株具有抗肿瘤活性的真菌。采用溶剂萃取、柱色谱及半制备HPLC等分离手段对来源于红树林植物老鼠簕Acanthus ilicifolius Linn.的菌株Aspergillus terreus(W-8)发酵产物进行了活性追踪分离,共得到5个化合物。通过理化性质及波谱技术,结合文献,鉴定其结构分别为aspulvinone H1(1)、aspulvinone H(2)b、utyrolactone I(3)t、errein(4)和3-propylbenzene-1,2-diol(5),其中化合物1的核磁数据为首次报道。采用MTT法初步评价了单体化合物的抗肿瘤活性,结果表明化合物4、5对A549、K562和Hela细胞均具有中等强度的细胞毒活性。  相似文献   
87.
Salinization and alkalinization are increasing problems in the world. Some land has been degraded to bare saline-alkaline soil where vegetation restoration is difficult because high toxic ionic content and pH are harmful to the survival of introduced plants. We grew Leymus chinensis with and without arbuscular mycorrhizal fungi (Glomus mosseae and G. geosporum) in either pots filled with soil from bare saline-alkaline land, or transplanted seedlings into field plots, to determine the influence of AM fungi on the reestablishment of this dominant grass species in bare degraded land. Association with AM fungi increased the absorption of N, P, K+, Ca2+, but decreased Mg2+, Na+ and Cl uptake under saline-alkaline stress. Therefore, higher K/Na, Ca/Na, P/Na, and P/Cl ratios were found in the inoculated plants. Plants inoculated with AM fungi accumulated significantly higher biomass, root/shoot ratio and tiller number than non-inoculated plants. AM fungi also significantly increased the survival of seedlings when they were transplanted into a bare saline-alkaline land in the field. The improvement of survival, growth and asexual reproduction of inoculated plants indicated that the plant-AM fungi mutualism could improve the reestablishment of vegetation in bare saline-alkaline soil, drive the vegetation restoration to a community dominated by original species.  相似文献   
88.
自雅浦海沟4个站位的12个沉积物样品中分离得到38株真菌菌株,基于形态观察和ITS序列信息对所得菌株进行分类鉴定,发现它们分别属于青霉属(Penicillium,17株)、曲霉属(Aspergillus,7株)、篮状菌属(Talaromyces,1株)、枝孢属(Cladosporium,6株)、赭霉属(Ochroconis,1株)、Meyerozyma属(1株)、梅拉菌属(Meira,1株)、Cystobasidium属(2株)、Wallemia属(1株)和红酵母属(Rhodotorula,1株)等10个属.其中青霉属、曲霉属和枝孢属菌株为优势菌株,分别占分离菌株总数的44.7%、18.4%和15.8%;而Wallemia属(节担菌纲)菌株是首次从深海环境中分离到.利用PCR技术在分离的深海真菌菌株中检测nir K和P450nor两种反硝化关键酶基因,结果显示nir K基因可在黄曲霉(Aspergillus flavus)、黑曲霉(Aspergillus niger)、杂色曲霉(Aspergillus versicolor)、枝孢菌(Cladosporium sp.)、枝状枝孢(Cladosporium cladosporioides)和产黄青霉(Penicillium chrysogenum)等6种真菌菌株中检测到,而P450nor基因仅在黄曲霉菌株中检测到.同时还通过富集培养方法从上述沉积物样品中分离获得两株反硝化枝孢菌.结果表明,雅浦海沟深海沉积物环境中存在着丰富的真菌资源,它们在深海环境氮循环中起着一定作用,这将增强人们对深海环境可培养真菌多样性及其生态作用的认识.  相似文献   
89.
鸭毛藻内生真菌Hypocreales sp.的化学成分研究   总被引:2,自引:0,他引:2       下载免费PDF全文
从采自大连近海的红藻鸭毛藻(Symphyocladia latiuscula)中分离到一株肉座菌目真菌(Hypocreales sp.),对其发酵代谢产物的化学成分进行了研究。利用正相硅胶柱层析、葡聚糖凝胶Sephadex LH-20柱层析、制备薄层层析(PTLC)以及重结晶等分离手段,并通过一维、二维核磁共振技术、质谱技术等从该菌发酵液中分离鉴定了10个化舍物:双酚A(1);邻羟基苯甲酸(2);吲哚甲酸(3);吲哚乙酸(4);N-乙酰色胺(5);(22E,24R)-麦角甾-7,9,22三烯-3β-醇(6);过氧化麦角甾醇(7);(22E,24R)-5α,6α-环氧麦角甾-8,22-二烯-3β,7α-二醇(8);(22E,24R)-麦角甾-7,22-二烯-6β-甲氧基-3β,5α-二醇(9);啤酒甾醇(10)。这些化合物均为首次从该菌中分离得到,其中化合物1为首次作为天然产物分离得到。  相似文献   
90.
对中国第29次南极科学考察获得的南极普里兹湾海域23个站位的深海沉积物样品进行了真菌分离培养,共获得了11个属的21株真菌,分别是:青霉属(Penicillium,9株)、枝孢属(Cladosporium,3株)、支顶孢属(Acremonium,1株)、短梗霉属(Aureobasidium,1株)、孢盘菌属(Botryotinia,1株)、散囊菌属(Eurotiales,1株)、外瓶霉属(Exophiala,1株)、镰孢菌属(Fusarium,1株)、丛赤壳属(Nectria,1株)、茎点霉属(Phoma,1株)、帚枝霉属(Sarocladium,1株).南极普里兹湾海域的真菌多样性较高,其中青霉属菌株最多,占总菌株比例为42.85%,是普里兹湾真菌中的优势属,其次为枝孢属菌株,占总菌株比例为14.29%.分别用尼罗红和氯化三苯基四氮唑(TTC)对这21株菌进行产油筛选,得到8株产油菌,分属于Penicillium(2株)、Aureobasidium(1株)、Cladosporium(1株)、Eurotiales(1株)、Exophiala(1株)、Fusarium(1株)、Sarocladium(1株)等7个属,这些产油菌产油量大致在20.1%到52.0%之间.对这8株菌的产油量和胞内脂肪酸成分进行分析,结果表明:这些产油菌所含的基本为短链脂肪酸,且不饱和脂肪酸含量较高,适合作为生物柴油的生产菌株.  相似文献   
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