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致病性副溶血弧菌生物膜形成特性研究 总被引：2，自引：0，他引：2
采用改良的微孔板法测定了12株弧菌的形成生物膜的效果,选择形成生物膜效果最好的副溶血弧菌ND-02,进一步研究了环境因子对其生物膜形成的影响。实验结果显示副溶血弧菌ND-02菌株在静置培养24～36 h后形成成熟的生物膜,在起始菌浓度为107～108CFU/mL形成生物膜的量最大;在30℃,NaCl浓度为3%～5%,pH偏弱碱性时的生物膜OD590值最大;C 2a+促进副溶血弧菌生物膜的形成,而M 2g+抑制生物膜的形成;副溶血弧菌在分别经大黄鱼表皮黏液、肠黏液和肝脏提取液包被的的基质上形成生物膜的作用明显,鳃黏液和脾脏提取液中次之,肌肉提取液包被后生物膜形成量最低。以上结果表明,副溶血弧菌ND-02菌株能形成稳定而明显的生物膜,而且生物膜的形成受温度、NaCl浓度、pH值等环境因子的影响。 相似文献
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采用改良微孔板法建立哈维氏弧菌Vibrio harveyi TS-628菌株生物被膜体外模型,并进一步研究环境因子对哈维氏弧菌体外形成生物被膜的影响。结果发现,哈维氏弧菌TS-628菌株可以在聚苯乙烯板中形成生物被膜,并且该菌生物被膜的形成受起始菌液浓度、温度、pH等理化因子的显著影响。温度为30℃、NaCl质量分数为3%—6%、pH为7、孵育时间为36h是哈维氏弧菌形成生物被膜的最佳条件。此外哈维氏弧菌在分别经表皮黏液、鳃黏液、肠道黏液、肝脏提取液、脾脏提取液、肌肉提取液包被的基质上成膜效果显著,其中在经肝脏提取液包被的基质上形成的生物被膜量显著高于在其他生物基质上形成的生物被膜量(p<0.01)。 相似文献
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研究了深圳海域2008年4月、9月的水体弧菌数量、种类组成及其分布,探讨了弧菌总数及各优势类群的数量分布与环境因子间的相关关系。结果表明:弧菌总数分布具有季节性,东部海域春季(4月)的弧菌数量高于秋季(9月)的,其均值分别为1.50×104 ,8.89×102 CFU/cm3;在西部海域秋季的略高于春季的,其均值分别为5.09×102,2.66×102 CFU/cm3;弧菌数量最高值出现在大亚湾(4.40×104 CFU/cm3)。弧菌的优势类群具有季节性分布特征:春季特有的优势类群有Vibrio gigantis类似种和V. splendidus类似种,秋季特有的优势类群有V. natriegens类似种;V. alginolyticus类似种是两个季节共有的优势类群,其数量春季高于秋季的。弧菌种类、数量与海水温度、盐度及细菌总数、Chl-a等环境因子有一定的相关性,其中盐度为弧菌种类及数量分布的主要影响因子。 相似文献
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从胶州湾污染区域的沉积物样品中筛选获得1株对重金属元素反应敏感的菌株,经鉴定为灰黄青霉(Penicillium griseofulvum),对该菌株在重金属胁迫下的生物学特征及酶的活性变化进行了研究,结果表明,一定量的重金属铜、锌离子对菌株产生显著的影响,并通过形态与色素变化的方式表现出来。当培养基中 Cu2+浓度为125 mg/dm3,Zn2+浓度为800 mg/dm3时,孢子萌发会完全受到抑制,同时菌丝也发生严重变异。菌株色素随着 Cu2+浓度的增加呈现从灰绿色到浅黄色的颜色变化,随着Zn2+浓度的增加呈现从灰绿色到白色的颜色变化。在菌株生长的离子浓度范围内,一定量的 Cu2+浓度能提高 CAT,GOD 酶的活性作用,在Cu2+浓度为25 mg/dm3时活性作用最强;在25~75 mg/dm3时,随着 Cu2+浓度的增加,活性作用逐渐减弱,浓度增加至100 mg/dm3时菌丝不能生长。Cu2+对菌体金属硫蛋白的影响不规则。在 Zn2+浓度为100~400 mg/dm3的培养基中,CAT,GOD酶和金属硫蛋白的活性作用随着Zn2+浓度的增加逐渐增强,在Zn2+浓度为400 mg/dm3时酶和金属硫蛋白活性达到最强。Zn2+浓度增加至600 mg/dm3 时,菌株不能生长。 相似文献
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通过物理模型试验研究海底子母管线分别在规则波加流和不规则波加流作用下的水动力特性。基于Morison方程,采用"等效直径法"分析得到子母管线拖曳力系数CD,惯性力系数CM和升力系数CL(CD+,CL-)。试验分别考察了流速比Uc/Uw,母管与海床间隙比e/D及子母管间的相对缝隙G/D对海底子母管线水动力系数的影响。结果表明水动力系数随Uc/Uw的增大而减小;当e/D<0.5时,海床对子母管线受力的影响比较明显,CD,CM及CL+均随e/D增大而减小,|CL-|随e/D增大而增大;对子母管间的相互影响也不可忽略,CD,CM和|CL-|均随G/D增大而减小,CL+值随G/D增大而增大。 相似文献
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为揭示赤点石斑鱼精子的超微结构及环境因子对其精子活力的影响,利用扫描电镜和透射电镜观察赤点石斑鱼精子的超微结构,设置不同梯度的温度、盐度、pH值及不同浓度的NaCl、KCl、CaCl2、MgCl2、EDTANa2溶液,探究这些因子对赤点石斑鱼精子活力的影响。结果表明:赤点石斑鱼成熟精子的结构特点是细胞核圆形或卵圆形,核内染色质致密,没有核泡(核空隙)。精子尾部细长,横切面为典型的"9+2"微管结构。温度、盐度、pH值等环境因子对精子活力的影响表明,精子活力的适宜温度范围为23~31℃,27.5℃时精子寿命最长为37min;适宜的盐度范围为15~35,盐度15时精子寿命最长为50min;适宜的pH范围为7~9,pH为9时精子的运动时间最长为33min。赤点石斑鱼精子在EDTANa2溶液中呈抑制状态,在400~700 mmol/L的NaCl溶液、400~600mmol/L的KCl溶液和500 mmol/L的CaCl2溶液中精子均具有较好的活动能力。在MgCl2溶液中赤点石斑鱼精子的活动能力不佳。赤点石斑鱼精子的最适温度范围与繁殖季节的最适水温范围符合,适宜盐度范围较广,对pH值的变化适应性较强。赤点石斑鱼精子在NaCl、KCl、CaCl2溶液中活力较佳,在MgCl2溶液和EDTANa2溶液中呈抑制状态。 相似文献
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为研究抚宁海湾扇贝养殖区浮游植物变化特征,探讨水质因子对浮游植物的影响,2020年5月—11月,每月测定该海域的主要水质因子,统计浮游植物。结果表明:共鉴定浮游植物69种,优势种33种;浮游植物密度(8.3~267.9)×104cell/L,5月份最高;生物多样性指数为0.458~3.747,均匀度指数0.099~0.796,丰富度指数0.933~4.755。海水水温范围11.8~26.8℃,盐度28.8~34.0,活性硅酸盐(SiO32–-Si)含量0.025~0.627mg/L,硝酸盐氮(NO3–-N)浓度0.057~0.284mg/L,均呈“上升-下降”趋势;pH范围为7.867~8.190,化学需氧量(COD)为0.260~1.415mg/L,活性磷酸盐(PO43–-P)0.003~0.006mg/L,变化趋势为“下降—上升”;对优势种与水质因子的分析表明,影响该海域浮游植物变化的主要环境因子为活性硅酸盐、盐度、活性磷酸盐和硝酸盐氮;裸藻门与活性磷酸盐、盐度呈正相关,与活性硅酸盐、硝酸盐氮呈负相关;甲藻门与活性硅酸盐呈正相关,与活性磷酸盐、硝酸盐氮呈负相关;隐藻门与活性硅酸盐、盐度成正相关,与硝酸盐氮呈负相关。 相似文献
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为构建泥蚶感染弧菌标准技术体系,本研究采用哈维氏弧菌浸泡感染和注射胁迫两种攻毒方式对泥蚶进行了急性毒性实验,观察泥蚶在菌液胁迫下的存活情况,分析哈维氏弧菌对泥蚶的半致死浓度。浸泡感染实验结果表明,随着感染水体中弧菌升高,泥蚶死亡起始时间和最大日死亡率时间均有所提前,泥蚶死亡情况呈现上升趋势,当浸泡浓度超过2×107CFU/mL,泥蚶15 d累计死亡率接近100%。注射胁迫实验结果表明,泥蚶死亡率与弧菌注射浓度呈显著正相关(r=0.964,P<0.01)。Probit回归分析结果显示,哈维氏弧菌浸泡感染泥蚶7 d后停止实验,15 d的半致死浓度(LC50)为1.35×107CFU/mL;注射胁迫下的96 h半致死剂量(96 h LD50)为2.12×107CFU/g,说明哈维氏弧菌对泥蚶有明显的毒害作用。研究结果为泥蚶对哈维氏弧菌耐受性提供数据参考,并且为泥蚶弧菌病防治提供了理论基础。 相似文献
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本研究提出了一种用于检测海水中锌离子（Zn2+）含量的电化学检测方法。该方法首先应用水热法合成SiO2@PDA-Sb复合材料，然后将该复合材料修饰到玻碳电极上制备SiO2@PDA-Sb-Nafion/GCE，利用差分脉冲阳极溶出伏安法（DPASV）对珠江口海水水样中Zn2+进行测定。研究结果表明，Zn2+在SiO2@PDA-Sb-Nafion/GCE上具有较强的溶出峰。在最优条件下，SiO2@PDA-Sb-Nafion/GCE对Zn2+浓度在1~1 000 nmol/L范围内可实现灵敏、准确的检测，Zn2+的检测出限为0.71 nmol/L。加标回收率实验显示Zn2+加标回收率为93.19%~100.12%，表明该方法可应用于现场海水样品Zn2+测定。本方法具有电极制作简单、稳定性和抗干扰性良好，能够提高现有测定方法的检测限和精确度，在现场海水检测痕量Zn2+具有较好的应用前景。 相似文献
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泥蚶、缢蛏和僧帽牡蛎呼吸与排泄的周年变化 总被引：1，自引：1，他引：0
于2005年5月至2006年3月对浙江沿岸重要的3种经济贝类泥蚶、缢蛏和僧帽牡蛎的呼吸率与排泄率进行了周年研究。结果表明:泥蚶、缢蛏和僧帽牡蛎耗氧率的变化范围分别为0.11~5.05 mg/（g·h）、0.77~5.97 mg/（g·h）和0.33~5.47 mg/（g·h）,排氨率的变化范围分别为21.51~1 078.63 μg/（g·h）,26.97~990.73 μg/（g·h）和32.12~1 378.67 μg/（g·h）;耗氧率与排氨率9月份最高,1月份最低。经单因素方差分析发现,3种实验贝类月际间的耗氧率与排氨率均存在极显著差异（p<0.01）,经配对T检验发现,缢蛏（SC）和僧帽牡蛎（SCA）之间的耗氧率存在着显著差异T（SC-SCA）=3.184,p=0.024）,泥蚶（TG）与缢蛏、僧帽牡蛎的耗氧率之间都不存在差异（T（TG-SC）=1.887,p=0.118;T（TG-SCA）=0.246,p=0.815）,泥蚶、缢蛏和僧帽牡蛎之间的排氨率的差异均不显著（T（TG-SC）=0.977,p=0.373;T（TG-SCA）=2.369,p=0.064;T（SC-SCA）=1.002,p=0.362）。3种贝类的耗氧率与排氨率均随温度的升高而升高,经回归分析发现,耗氧率和排氨率与温度的变化均呈较显著的幂指数性相关lnY=lna+blnT（Y=aebT）。泥蚶呼吸排泄O:N变化范围为4.69~28.55,缢蛏和僧帽牡蛎的O:N变化范围分别为:4.68~37.89和3.04~10.27。 相似文献
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A study of the mesoscale distribution of phytoplankton communities observed along the Portuguese upwelling coast in 1985–1986 made it possible to identify an assemblage composed by the coccolithophores Helicosphaera carteri, Syracosphaera pulchra and Coronosphaera mediterranea. The assemblage was consistently present in the coast in the following years (1991, 1992, 1994, 2003 and 2005) and from 1992 onwards, Rhabdosphaera clavigera was recognised as being part of it, although in low concentrations During late summer, this group of species showed higher affinities with upwelling waters of subtropical origin (ENACWst) on the SW coast. At the end of the upwelling season, in autumn, the assemblage was advected to the NW shelf due to the intensification of the poleward surface circulation or meridional seasonal changes of environmental conditions. The species maximum abundances were not coincident in space: H. carteri developed at the central part of the western coast while blooms of S. pulchra and C. mediterranea generally occurred further south, such as at the upwelling centre of cape S. Vicente. Syracosphaera pulchra blooms were characterised by lower concentrations of C. mediterranea and vice-versa. The above patterns were recurrent along the years but the relative abundance of each species appeared related to the interannual variability of physical conditions as the upwelling. 相似文献
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通过灌胃将绿色荧光蛋白标记的病原性河流弧菌导入青石斑鱼消化道内,追踪标记菌在青石斑肠道中的黏附和定植及对肠道消化酶活性的影响。结果表明,青石斑前肠和中肠在河流弧菌灌胃12 h即可检出,前肠在24 h达到峰值,大约为7.1×105 cfu/g,中肠则在36 h达到峰值,约为5.39×105 cfu/g,而后肠则是在24 h才开始检出,且检出时即达到峰值,但仅为2.44×104 cfu/g,说明青石斑鱼的前肠和中肠都是河流弧菌的主要黏附部位。灌胃96 h后前肠和中肠仍有标记菌存在,但在后肠已检测不到标记菌,反映出标记菌已在前肠和中肠定植下来,但没有在后肠定植。此外,标记河流弧菌的定植能够显著降低前肠蛋白酶活性和淀粉酶活性以及后肠脂肪酶活性。研究结果说明,病原性河流弧菌可通过黏附定植于鱼类肠道影响鱼类肠道消化酶活力,这可能是病原性河流弧菌引发鱼类病害的原因之一。 相似文献
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旋链角毛藻对中肋骨条藻化感作用的影响因素 总被引：1，自引：0，他引：1
在已知旋链角毛藻对中肋骨条藻具有化感作用的前提下,进行了温度、生长时期、光照、细菌等因素对旋链角毛藻化感作用的影响、化感物质的萃取及粗提物对中肋骨条藻的化感效应检验等实验,研究了旋链角毛藻化感物质的性质、降解特点,并初步测定了化感物质的结构。结果表明:旋链角毛藻化感作用与生长时期有关,指数期滤液化感作用强于衰亡期;旋链角毛藻的化感物质在50℃以下保持稳定,光和细菌均引起旋链角毛藻化感物质的降解,且细菌降解强于光降解;旋链角毛藻的乙酸乙酯萃取物具有明显的化感活性,该萃取物在255～260 nm处有特征吸收峰。综合以上结果,推测旋链角毛藻化感物质可能为分解温度在50℃以上的易被光和细菌降解的苯衍生物,从极性上看较易溶于乙酸乙酯。 相似文献
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本研究基于线粒体DNA分子标记NADH脱氢酶亚基1基因(ND1)部分序列分析了印度-西太平洋海域的胡椒鲷属及少棘胡椒鲷属共16种胡椒鲷鱼类的系统进化关系。采用最大简约法及最大似然法构建了系统进化树。进化树上,16种胡椒鲷鱼类共形成两个形态特征截然不同的类群,其中类群一的种类体表具有各种鲜艳的颜色与多变的斑纹,主要分布在西太平洋地区;类群二的种类颜色灰暗单一,少数体表具有暗色斑点与条纹,大多数分布在印度洋地区。此外,进化树上,少棘胡椒鲷属的种类都位于胡椒鲷属的类群一内部,与斑胡椒鲷,暗点胡椒鲷形成的姐妹种有较近的亲缘关系。基于遗传距离的数据,少棘胡椒鲷属与胡椒鲷属间的平均遗传距离小于胡椒鲷属内部种间的遗传距离,显示出少棘胡椒鲷属与胡椒鲷属有非常近的亲缘关系,支持少棘胡椒鲷归类于胡椒鲷属的观点。 相似文献
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Whaling as a commercial enterprise is now defunct, not least due to the moratorium placed on it by the International Whaling Commission (IWC) almost 20 years ago. However, two distinct groups, one in favor of ‘sustainable’ whaling and one completely opposed to any killing of whales, continue to argue at the IWC and other political arenas. Almost ignored in this debate is the current growth of the whale watching industry, a logical alternative use for whale populations. Based on ecological and socio-economic criteria, the potential for whale watching is estimated for maritime countries that do not currently engage in this industry. Results suggest that whale watching could generate an additional 413 million USD (2009) in yearly revenue, supporting 5,700 jobs. Together with current global estimates, this would bring the total potential for the whale watching industry to over 2.5 billion USD in yearly revenue and about 19,000 jobs around the world. These results are discussed from an economic and conservation policy perspective, with emphasis on potential benefits and limitations. 相似文献
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To investigate feeding habits of juvenile flounder (Platichthys flesus) and turbot (Psetta maxima) in relation to habitat characteristics a field survey with push net sampling was conducted in nursery areas with different ecological characteristics in the northern Baltic proper. Sampling sites were stratified to cover several different habitat types defined by substrate and wave exposure. Apart from flatfishes and epifauna, samples of macrofauna, meiofauna and hyperbenthic planktons were collected from each site together with data on vegetation, depth, salinity, temperature and turbidity. The diet differed between species where flounder diet was dominated by chironomids, copepods and oligochaetes while turbot apart from chironomids had a high incidence of amphipods, gobies and mysids. In both species there was a shift in diet with size, although this shift was influenced by the habitat. Among the environmental variables investigated, wave exposure was found to significantly influence flounder diet. Food preference in the most exposed areas was dominated by oligochaetes and copepods instead of chironomids, which dominated in sheltered areas. This study shows that habitat characteristics can have a major influence on feeding habits of juvenile flatfish. 相似文献
19.
The decoupling of trophic interactions could be one of the severe consequences of climate warming in aquatic systems. The timing of phytoplankton blooms, in particular, can affect competition within the plankton community as well as food-web interactions with zooplankton and fish. Using long-term data from Helgoland Roads in the southern North Sea, we examine diatom seasonality, using three representative diatom species combined with environmental and copepod time series over the last four decades. The long-term annual abundances of Guinardia delicatula, Thalassionema nitzschioides and Odontella aurita exhibited interannual variations and dissimilar cyclic patterns during the time period under study (1962-2008). Of the three diatoms, G. delicatula showed a significant trend towards earlier bloom timings for 1962-2008 and a later decline of its abundance over time was found. Grazing and water transparency explained most of the bloom timing fluctuations of the diatoms considered. The annual timing of occurrences of each diatom species was correlated with their preceding concentrations. Earlier bloom timings occurred when autumn/winter concentrations were higher than average and later bloom timings occurred when autumn/winter concentrations were lower than average. Different environmental and predation variables related to the diatom bloom timings were found suggesting that climate warming might not affect the onset of the blooms of the three diatom species in the same manner. The results of the multiple linear regression analyses showed that the timings of decline of the three diatoms were mainly correlated with decreasing nutrient concentrations. Sunshine duration could prolong the duration of the blooms of T. nitzschioides and O. aurita provided that enough nutrients were available. In the case of G. delicatula, however, sunshine duration was negatively correlated with its end of the growth period. G. delicatula and T. nitzschioides showed later decreases in abundances under warmer spring and summer temperatures. Such species specific differences in the sensitivity to the forcing variables could lead to shifts in community structure and could ultimately have wider implications to the overall ecosystem health of the North Sea. 相似文献
20.
原油WSF对三种海洋鱼类肝微粒体EROD活性的诱导和恢复的比较 总被引：1，自引：1，他引：0
研究了实验室条件下原油水溶性组分(WSF)暴露对黑鲷、黄鳍鲷和褐菖鲉肝微粒体EROD活性的剂量-效应,时间-效应和恢复过程。实验结果表明,在剂量诱导实验中,褐菖鲉肝EROD活性在原油WSF浓度为50μg/dm3时呈现生物统计学上的显著差异,而黑鲷和黄鳍鲷肝EROD活性在75μg/dm3时才呈现生物统计学上的显著差异;褐菖鲉肝EROD活性诱导倍数最高,但黑鲷的诱导浓度范围较广。在时间诱导实验中,在40μg/dm3原油WSF暴露下黄鳍鲷肝EROD活性在2 d时首先呈现显著差异;三种鱼肝EROD活性均在第4天达到最高,并呈现显著性变化,此后随着暴露时间的延长而逐渐下降并接近对照组水平。在恢复实验中三种鱼肝EROD活性下降并恢复到对照组水平。研究结果表明:对于石油污染物,黑鲷、黄鳍鲷和褐菖鲉肝EROD活性都可以作为污染生化效应监测指标,然而就三种鱼类比较而言,褐菖鲉最敏感,更适合于作为石油类污染及其生化效应,尤其是低剂量效应的监测生物。 相似文献