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11.
12.
海洋木栖真菌抗菌活性的初步研究 总被引:6,自引:0,他引:6
从福建厦门海沧、集美及漳州浮宫等地采集到的红树林等海洋潮间带的各种腐木样品中分离得到176株海洋木栖真菌,对其进行抗菌活性检测.其结果表明共有96株海洋木栖真菌对大肠杆菌、枯草杆菌及白色假丝酵母中的一种或多种拮抗指示菌具有抑制作用,占供测菌株总数的54.5%.在这些活性菌株中,红树源菌株拮抗比例为30.2%,非红树源菌株拮抗比例为69.8%.具有抗菌活性的菌株主要分布于15个属中,包括木霉Trichoderma、青霉Penicillium、拟青霉Paecilomyces和一些不产孢的分类群.某些稀有真菌如盘多毛孢Pestalotia、茎点霉Phoma也具有一定的抗菌活性. 相似文献
13.
Natalia V. Zhukova 《Ocean Science Journal》2005,40(3):34-42
Variation in the microbial biomass and community structure found in sediment of heavily polluted bays and the adjacent unpolluted
areas were examined using phospholipid fatty acid analysis. Total microbial biomass and microbial community structure were
responding to environmental determinants, sediment grain size, depth of sediment, and pollution due to petroleum hydrocarbons.
The marker fatty acids of microeukaryotes and prokaryotes - aerobic, anaerobic, and sulfate-reducing bacteria -were detected
in sediments of the areas studied. Analysis of the fatty acid profiles revealed wide variations in the community structure
in sediments, depending on the extent of pollution, sediment depth, and sediment grain size. The abundance of specific bacterial
fatty acids points to the dominance of prokaryotic organisms, whose composition differed among the stations. Fatty acid distributions
in sediments suggest the high contribution of aerobic bacteria. Sediments of polluted sites were significantly enriched with
anaerobic bacteria in comparison with clean areas. The contribution of this bacterial group increased with the depth of sediments.
Anaerobic bacteria were predominantly present in muddy sediments, as evidenced from the fatty acid profiles. Relatively high
concentrations of marker fatty acids of sulfate-reducing bacteria were associated with organic pollution in this site. Specific
fatty acids of microeukaryotes were more abundant in surface sediments than in deeper sediment layers. Among the microeukaryotes,
diatoms were an important component. Significant amounts of bacterial biomass, the predominance of bacterial biomarker fatty
acids with abundance of anaerobic and sulfate-reducing bacteria are indicative of a prokaryotic consortium responsive to organic
pollution. 相似文献
14.
The Fauna of Floating Cyanobacterial Mats in the Oligohaline Eulittoral Zone off Hiddensee (South-west Coast of the Baltic Sea) 总被引:2,自引:0,他引:2
Abstract. The fauna — including macrofauna, meiofauna, and large ciliates — of floating cyanobacterial mats in a brackish shallow-water area was studied by analysing six 20 cm2 pieces of mat. Although these microbial aggregations were scarcely 1 cm thick, their total meiofauna abundance was about five times as high as in the uppermost 4 cm of the adjacent sediment. The mat fauna was dominated by harpacticoids, although large ciliates, rotifers, nematodes, and oligochaetes were also markedly more abundant than in the sediment. All species occurring in the mats were members of the surrounding sediment fauna. Out of the 47 species found, only a few, among them predominantly the harpacticoid, Mesochra lilljeborgi B oeck , 1864, and the nematode Daptonema setosum ( bütschli , 1874), accounted for the majority of the individual abundance in the mats. Both are regularly found in sulphidic biotopes near Hiddensee. As SEM micrographs revealed, the oligochaete Paranais litoralis (O. F. M üller , 1788) and the harpacticoid Cletocamptus confluens (Schmeil, 1894) were apparently optimal substrates for dense lawns of cyanobacteria. This indicates possible close interactions between the meiofauna and these microbiota. The frequent predation of histophagous ciliates on nematodes and harpacticoids, which were probably weakened by oxygen deficiency and/or high sulphide concentrations, were not only a sign of a generally neglected pathway in the food chain, but also impressively emphasized the huge variety of interactions taking place between meio- and microfauna within this specific benthic microcosm. Because of their floating character, the mats can play an important role in the dispersal of benthic fauna. 相似文献
15.
利用臭氧氧化实现复合生物反应器污泥减量 总被引:3,自引:0,他引:3
采用复合生物反应器,对应用臭氧氧化实现污泥减量进行了研究。2个相同的复合生物反应器平行运行,1个作为对照系统,1个作为氧化系统。反应器内装有半软性填料,投加量为10%。曝气池中悬浮污泥浓度为1 500 mg/L左右,生物膜浓度为2 000 mg/L左右。试验结果表明,随着臭氧氧化污泥比例的增加,污泥表观产率系数也随之降低,当臭氧投量为0.05 g O3/gSS,每天氧化的污泥分别为反应器内污泥的10%,20%,30%时,污泥表观产率系数分别减少28.2%,44.9%,75.8%。虽然随着污泥氧化比例的增大,氧化系统出水CODcr略有增加,但氧化系统仍能保持其生物处理能力,CODcr去除率在92%以上;2个系统之间氨氮的去除率相差不大,氧化系统的硝化能力基本没有受到臭氧氧化的影响。 相似文献
16.
对海洋来源的Vibro sp.QY102的产褐藻胶裂解酶的发酵条件进行研究。结果表明,该菌株最适液体培养基成分为(w/v):0.5%褐藻酸钠;0.4%蛋白胨;0.3%KH2PO4;0.7%K2HPO4.3H2O;2%NaCl;0.01%MgSO4.7H2O,pH=6.0。按3%的接种量接入培养基,30℃150 r/min振荡培养120 h,产酶达到10.2 U/mL,为优化前的4.5倍。Mg2 是该菌株产酶所必需的,这在其他褐藻胶裂解酶生产菌株中未见报道。该菌株产酶发酵条件的研究,为褐藻胶裂解酶的大规模制备及应用奠定了基础。 相似文献
17.
华北地台中元古代碳酸盐岩中的微生物成因构造及其生烃潜力 总被引:6,自引:3,他引:3
华北地台中元古界主要由环潮坪石英砂岩、浅海碳酸盐岩和浅海—泻湖相暗色页岩3种沉积相组合构成,以陆表海浅水碳酸盐岩占主导。碳酸盐岩中除含有丰富的微古植物、宏观藻类和微生物建隆外,还发育大量的微生物成因构造(MISS)和微生物诱发的碳酸盐沉淀(MMCP)。微生物席和MISS构造在高于庄组上部(约1.6 Ga)和雾迷山组下部(约1.45 Ga)碳酸盐岩中尤为发育,表明活跃的微生物活动和高有机质产量。在石化微生物席中,发现有丝状、球状细菌化石和草莓状黄铁矿;围岩中发现有针状文石、花瓣状重晶石、放射状菱铁矿、铁白云石和葡萄状碳酸盐胶结物等多种自生碳酸盐矿物,指示甲烷厌氧氧化(AOM)导致的自生碳酸盐沉淀。中元古代的温暖气候和海洋分层、缺氧、硫化条件有利于微生物的高生产量和高有机质埋藏率。气隆构造和核形石状碳酸盐结核反映浅埋藏条件下活跃的成烷作用和甲烷排放,围岩和MMCP中富沥青质。华北地台中元古界富微生物席碳酸盐岩有良好的生烃潜力,有可能形成重要的烃源岩。据微生物席、MISS构造及MMCP的研究,初步估算华北地台中元古代碳酸盐岩的概略生烃潜力约为10×108t石油当量。 相似文献
18.
氧化锰矿物的生物成因及其性质的研究进展 总被引:5,自引:0,他引:5
土壤中的氧化锰矿物是原生矿物风化和成土过程的产物,是最具反应活性的一类矿物,决定着环境中许多物质的形态、迁移和转化,在元素生物地球化学循环中起着重要的作用,其形成机制和环境效应备受关注。已有的研究表明,环境中氧化锰的形成与微生物作用紧密相关,微生物作用可使自然环境中的Mn(Ⅱ)氧化速率提高105倍。参与Mn(Ⅱ)氧化的微生物在环境中广泛存在,已知的典型锰氧化细菌分布在变形菌门、放线菌门或厚壁菌门,它们均通过胞外聚合物中的多铜氧化酶来催化氧化Mn(Ⅱ)。细菌氧化Mn(II)成Mn(Ⅳ)是酶催化的两个连续的快速单电子传递过程,Mn(Ⅲ)在溶液中以与酶结合的瞬时中间态出现。生物形成氧化锰的最初形态为层状锰矿物,与δ-MnO2或酸性水钠锰矿很类似,且结晶弱,粒径小,锰氧化度高,结构中的八面体空穴多,因而比化学形成的氧化锰具有更强的吸附、氧化等表面活性。环境中Mn(Ⅱ)微生物氧化及形成的Mn(Ⅲ)中间体与碳、氮、硫等生命元素的地球化学循环的关系令人关注。 相似文献
19.
Stratigraphy, sedimentology and bulk organic geochemistry of black shales from the Proterozoic Vindhyan Supergroup (central India) 总被引:1,自引:0,他引:1
Four organic-rich shale units of the Proterozoic Vindhyan sedimentary succession have been scanned to reveal their origin
and hydrocarbon potential. The wavy-crinkly nature of the carbonaceous laminae is suggestive of a microbial mat origin of
the shales. These shales are thus different from Phanerozoic black shales which typically exhibit planar laminae. The hydrocarbon
potential of the black shale units has been evaluated by Rock-Eval pyrolysis. Total organic carbon content of many of the
shales exceeds 1%. The meanT
max for the black shales translate to a vitrinite reflectance range of 2.05-2.40% Rm based on standard conversion techniques.
These shales have reached the catagenetic stage near the beginning of anthracite formation. 相似文献
20.
微生物絮凝剂的絮凝性能研究 总被引:15,自引:0,他引:15
研究了微生物絮凝剂“Dtjm-1”的絮凝性能,通过改变废水初始pH值,调整废水中阳离子种类、阳离子浓度及改变发酵液的离心条件和投加体积,得出絮凝剂“Dtjm-1”的最佳絮凝条件为:废水pH值7.2-8.0;能较好促进絮凝的离子有Al^3 ,Ca^2 ,它们最适合的浓度为每升废水中加入0.75-1g/L;发酵液的投加体积为(0.075-0.080):1(体积比);发酵液较好的离心条件为n=4000r/min,t=30min。通过不同废水絮凝效果试验表明,得出絮凝剂“Dtjm-1”具有很好的絮凝作用和脱色性能。 相似文献