青阳参内生真菌分离与鉴定

目的:从云南民间药用植物青阳参的根、茎和叶中分离内生真菌,并进行分类鉴定。方法:利用平板分离法分离内生真菌。通过显微形态观察分类鉴定。结果:从植物根、茎和叶中共分离获得34株内生真菌,其中25株真菌经鉴定归属为5目,7科,12个属。结论:结果表明青阳参植物内生真菌存在多样性,不同部位内生真菌的数量、组成与种群分布存有差异。     

活性内生真菌EZG0807的鉴定及其生物学特性研究

从传统中药温莪术根部分离出一株活性内生真菌EZG0807,采用分子生物学与形态学观察相结合的方法对其进行鉴定。通过PCR扩增该菌ITS区域并在NCBI中进行同源性分析,构建系统发育树,结合形态学观察,鉴定其为串珠赤霉菌Gibberella moniliformis,是一种兼性内生真菌,既是植物和昆虫病害的病原体,又能作为内生真菌促进宿主植物的生长;为了更好地了解和利用活性菌株EZG0807,对其进行了生物学特性及发酵条件优化的研究。该菌除对半乳糖和(NH4)2SO4利用度较差外,能利用多种常见的培养基;其生长温度范围为15³5℃,最适生长温度为30℃;菌株生长pH范围为4.035℃,最适生长温度为30℃;菌株生长pH范围为4.0¹0.0,最适pH为7。根据菌株EZG0807的生长特性及前期单因素实验结果,经响应面优化后的发酵条件为发酵温度28.72℃,初始pH值6.76,发酵时间10.02 d,测得其发酵液对普通变形杆菌的抑菌圈直径为25.6 mm,比优化前提高24.9%。熟悉该菌株的生长培养条件和营养需求,可为后续研究其代谢产物奠定基础。     

清香木内生菌对酪氨酸酶活性的影响

目的:探讨清香木内生菌对酪氨酸酶活性的影响。方法:对新鲜清香木的茎和根部位进行内生真菌的分离,经显微鉴定菌株分别为木霉属、镰孢属和假丝酵母属,然后将菌株的发酵液用多孔酶标板法进行酪氨酸酶抑制活性的检测。结果:茎皮部的PZ-6-2对酪氨酸酶活性抑制作用最强,PZ-4次之;根皮部的QZ-1抑制活性也较强。结论:清香木内生菌对酪氨酸酶活性具有一定的抑制作用。     

外源激素与内生真菌互作对醉马草低温胁迫下种子萌发的影响

低温是限制种子萌发的一个关键因子,而外源激素和内生真菌分别通过外部介导和内部调控的途径来提高低温环境下种子的萌发能力.本研究以感染内生真菌(E+)和未感染内生真菌(E-)醉马草(Achnatherum inebrians)种子为材料,利用不同浓度的水杨酸(SA)或脱落酸(ABA)溶液浸泡种子,测定10℃条件下醉马草种子的发芽率、发芽指数、胚芽长、胚根长和幼苗含水量,探讨外源激素与内生真菌互作对醉马草种子低温条件下萌发的影响.结果发现,SA或ABA处理能促进醉马草E+、E-种子的萌发;高浓度SA或ABA处理下则表现出抑制作用,其中高浓度(0.2 mmol/L)ABA对种子发芽抑制作用显著(P<0.05);SA与内生真菌互作对种子发芽率、发芽指数和胚根长有显著(P<0.05)促进作用;ABA与内生真菌互作对种子发芽指数、胚芽长、胚根长和幼苗含水量有显著(P<0.05)的促进作用.表明一定浓度范围的SA或ABA与内生真菌互作,能够促进醉马草种子在低温胁迫条件下的萌发力.     

6株大型真菌发酵提取物的抑菌及细胞毒活性研究

目的:对6株广东大型真菌红汁乳菇(Lactarius hatsudake)G027、鸟巢菌(Cyathus sp.)G026、革耳菌(Panus sp.)G028、光亮小红孔菌(Pycnoporellus fulgens)G033、菌核斗菇(Lentinus tuber-regium)G025和有柄灵芝(Ganoderma gibbosum)G036的发酵提取物进行抑菌和细胞毒活性研究。方法:分别采用滤纸片扩散法和SRB法对这6株大型真菌的发酵提取物进行抑菌和细胞毒活性研究。结果:菌株G027、G028、G026和G033对金黄色葡萄球菌具有显著的抑菌活性,其抑菌圈直径分别为25.00、18.23、14.96和14.30mm;6株大型真菌对神经胶质瘤细胞SF-268、乳腺癌细胞MCF-7、大细胞肺癌细胞NCI-H460和人肝癌细胞HepG-2均有不同程度的抑制作用,其中菌株G027的活性最为显著,对这4种肿瘤细胞株的IC50值分别为2.84、6.44、11.88和2.96μg/mL。结论:6株大型真菌具有抑菌和(或)细胞毒活性,值得进一步深入研究。     

巨紫根水葫芦对平原水库富营养化水体净化效果的研究

以普通水葫芦和紫根水葫芦为研究对象,考察了两种水葫芦植物对平原水库水体氮磷的净化效果。结果表明,紫根水葫芦对总氮、氨氮和总磷的去除效果优于普通水葫芦,其单位质量植物去除水中氮磷的量更多,且生物量增长比普通水葫芦慢。     

Comparative effects of biostimulation and phytoremediation on crude oil degradation and absorption by water hyacinth (Eichhornia crassipes [Mart.] Solms)

This study investigated the effects of inorganic fertilizer (urea) amendment on crude oil degradation and uptake by water hyacinth (Eichhornia crasssipes). Experimental units (fresh borehole water) were spiked with crude oil at four different concentrations and then were randomly assigned fertilizer (urea) at three different concentrations. Crude oil degradation and absorption were determined monthly by measuring total petroleum hydrocarbon (TPH) in water column and water hyacinth, respectively. The water hyacinth planted in the control absorbed significantly (p?相似文献   

Establishment of the moth: Niphograpta albiguttalis (Warner) (Lepidoptera: Pyralidae), a biological control agent of water hyacinth (Eichhornia crassipes) in waterways of Lagos and Ogun states,southwestern Nigeria

The moth Niphograpta albiguttalis was found infesting water hyacinth on waterways in Nigeria in 2009 in the areas of Badagry, Ejirin and Epe in Lagos State and Iwopin in Ogun State. This moth has not been released in Nigeria but it was released as a biological control agent for water hyacinth in Ghana in 1996 and in Benin in 1993. It is not reported to have established in those countries, but it would appear that as a result of those releases N. albiguttalis is now present in Nigeria. The larval instars found were damaging only water hyacinth with bulbous petioles. The larval developmental periods ranged between 10 and 15 days (n = 3).     

Carbon source utilization‐based metabolic activity of Salmonella Oranienburg and Salmonella Saintpaul in river water

The presence of introduced or non‐native bacteria in river water can create a selective pressure due to their ability to overcome fluctuations in physicochemical conditions and carbon source availability. The carbon source concentrations (monosaccharides and polysaccharides), physicochemical parameters (turbidity, total dissolved solids, biochemical oxygen demand, temperature and pH) and metabolic activity of Salmonella Oranienburg and Saintpaul were determined in water from the central Sinaloa state rivers. This study's results revealed that the carbohydrate availability and physicochemical conditions of river water make it a suitable niche for the establishment of Salmonella serotypes. Metabolic profiles showed that Salmonella Typhimurium could consume a wide variety of carbon sources but only at moderate levels; in contrast, Salmonella Oranienburg and Salmonella Saintpaul demonstrated intense carbon source utilization of a limited diversity of carbon sources. Carbohydrates, amino acids and carboxylic acids were the metabolites most utilized by the environmental Salmonella strains, demonstrating their superior ability to adapt to and survive in river water.     

建筑排水水封蒸发初步实验研究

水封是建筑排水系统的重要组成部分,水封损失将会严重影响排水系统正常运行和产生不良的后果。而蒸发现象是引起水封损失和破坏的因素之一,如何提高水封可靠性问题越来越受行业的关注,也是当今行业研究的课题。本次实验历时3个多月对不同水封容量、不同水封高度、不同水封比的水封,在不同温度、不同湿度、不同遮盖情况下,对水封静态蒸发损失情况进行测量与分析,有助于提高人们对水封静态蒸发损失的认识。     

滤池反冲洗废水回用试验研究

研究了滤池反冲洗废水回用,与原水一并处理时对浊度去除效果的影响。结果表明,对于中低浊度原水,加入一定比例（10％～15％）的反冲洗水,不但可以回收反冲洗废水,而且改善了混凝性能,提高了反应沉淀效果,节省了混凝剂投加量,具有较好的经济效益和环境效益。     

浅谈建筑给排水工程的质量控制

针对当前建筑给排水施工中施工方管理和施工工艺两方面存在的主要问题,介绍了建筑给排水施工监理的质量控制重点,分别阐述了建筑给排水施工监理的具体措施及工程验收阶段控制重点,以期指导实践。     

A simple purification and activity assay of the coagulant protein from Moringa oleifera seed

Use of extracts from Moringa oleifera (MO) is of great interest for low-cost water treatment. This paper discusses water and salt extraction of a coagulant protein from the seed, purification using ion exchange, its chemical characteristics, coagulation and antimicrobial properties. The coagulant from both extracts is a cationic protein with pI greater than 9.6 and molecular mass less than 6.5 kDa. Mass spectrometric analysis of the purified water extract indicated that it contained at least four homologous proteins, based on MS/MS peptide sequence data. The protein is thermoresistant and remained active after 5h heat treatment at 95 degrees C. The coagulant protein showed both flocculating and antibacterial effects of 1.1--4 log reduction. With samples of high turbidity, the MO extract showed similar coagulation activity as alum. Cecropin A and MO extract were found to have similar flocculation effects for clay and microorganisms. Simple methods for both the purification and assay of MO coagulating proteins are presented, which are necessary for large-scale water treatment applications.     

饮用水除嗅味技术的研究进展

介绍了饮用水中致嗅味物质的种类及来源,概括了国内外对饮用水中嗅味控制技术的研究进展,总结了氧化预处理、吸附预处理、生物处理等技术法对饮用水嗅味的去除效果,对今后自来水厂生产饮用水的工艺改进具有指导意义。