海藻提取物抗炎活性的筛选

分属绿藻门、红藻门、褐藻门的海藻样品于2000年采于山东青岛和威海沿海，首次采用人白细胞弹性蛋白酶体外筛选技术对39种海藻样品的甲醇提取物进行了抗炎活性筛选，以期从海藻中寻找天然抗类风湿性关节炎等炎症性疾病的药物活性前体。结果表明，18种海藻（7种褐藻，11种红藻）对HLE有抑制活性，而绿藻缺乏抗HLE活性。这18种海藻中，7种表现出较强的抑制活性，分别为：鸭毛藻、海头红、江蓠、细枝软骨藻、粗枝软骨藻、小粘膜藻和绳藻，其中尤以绳藻的抑制活性最强（在浓度为25μg/ml时可达98．9％）。     

海藻提取物环氧加酶-2 抑制活性研究

系统采集中国沿海10种代表性海藻,进行有效成分提取与粗分;利用昆虫杆状病毒表达系统克隆人COX-2基因,并在昆虫Spodoptera frugiperda(sf9)细胞中表达获得COX-2蛋白;以花生四烯酸为底物,通过测定前列腺素PGE2的生成浓度,测定海藻不同部位对COX-2酶的抑制活性.结果表明,萱藻(Scytosiphon lomentarius)乙醇提取物、鼠尾藻(Sargassum thunbergii)和刺松藻(Codium fragile)乙酸乙酯相、松节藻(Rhodomela conferroides)正丁醇相表现出良好的COX-2酶抑制活性(质量浓度为10μg/mL时,抑制率大于50%).首次对上述海藻进行COX-2酶抑制活性研究,其中萱藻乙醇提取物、鼠尾藻和刺松藻乙酸乙酯相、松节藻正丁醇相表现出良好的COX-2抑制活性.     

海藻乙醇提取物抗菌活性的研究

分属绿藻门、红藻门、褐藻门的海藻样品于 2 0 0 0年 5月采于山东青岛和威海附近沿海 ,将海藻样品的乙醇提取物进行薄层层析分离和抗大肠杆菌、金黄色葡萄球菌活性测定。结果表明 ,抗大肠杆菌活性较强的海藻样品有 :鸭毛藻、酸藻、松节藻和孔石莼的水相 ;抗金黄色葡萄球菌活性较强的提取物有 :鸭毛藻、海黍子、松节藻、小粘膜藻的乙酸乙酯相以及酸藻的水相。从不同门类海藻的抗菌活性看 ,褐藻最强 ,红藻次之 ,而绿藻活性最弱。薄层层析分离得到 1 6个层析带具有抗金黄色葡萄球菌活性 ,1 1个层析带具有的抗大肠杆菌性。其中褐藻门的酸藻、海黍子的 3个层析带具有很强的抗金黄色葡萄球菌活性 ,酸藻的 2个层析带也能强烈地抑制大肠杆菌的生长。在同样的实验条件下 ,对常见抗生素进行的对照实验表明 ,这 5条层析带的活性比常见的抗生素高。     

海参酶解物中抗老年痴呆相关活性及成分初步研究

通过国标方法分析海参酶解原液的基本营养成分;并将海参酶解原液用不同极性的有机溶剂进行提取,利用乙酰胆碱酯酶抑制活性自显影的方法进行活性组分的追踪。利用硅胶柱层析、Sephadex LH-20凝胶柱、高效液相色谱逐步纯化,得到具有较高乙酰胆碱酯酶抑制活性的组分;另外,采用MTT法考察海参酶解液总脂溶性组分对小胶质细胞(BV-2细胞)生长的影响;并利用LPS诱导细胞建立细胞炎症模型,分别采用Griess法和ELISA法检测其对LPS诱导的BV-2细胞中NO和IL-6水平的影响。结果表明:海参酶解原液含有丰富的钙、锌等矿物质,含量较高的多不饱和脂肪酸和必需氨基酸其提取物中具有乙酰胆碱酯酶抑制活性的薄层层析斑点均无明显紫外与荧光吸收,其中活性最强组分C4-2-E在浓度为0.25g/L时对乙酰胆碱酯酶的抑制率为91.04%;海参酶解液总脂溶性组分在一定的浓度范围内对BV-2细胞均无显著的抑制作用,并且能够显著的抑制LPS诱导的BV-2细胞所产生的NO和IL-6的分泌。故海参酶解液的脂溶性成分可能具有一定的抗神经炎症和老年痴呆作用,具体活性物质的化学结构还需进一步分析鉴定。     

中国经济海藻提取物生物活性

分别采用MTT法、双碟法、酶标法、光度法和增重法测定了广西涠洲岛、广东硇洲岛、山东青岛和威海沿岸具有代表性的大型海藻提取物的抗肿瘤、抗菌、免疫、抗炎、抑制α-葡萄糖苷酶和抗氧化的活性。结果表明，鸭毛藻、松节藻、小粘膜藻和点叶藻的甲醇提取物具有选择性细胞毒活性；酸藻水相、鸭毛藻的乙酸乙酯相有较强的抗菌活性；金膜藻、网地藻、石莼和萱藻的甲醇提取物有较好的免疫抑制活性；三叉仙菜、龙须菜、海萝、绳藻和小粘膜藻的甲醇提取物有较好的免疫增强活性；细枝软骨藻、粗枝软骨藻和绳藻的甲醇提取物有显著的抗炎活性；松节藻、肠浒苔和扁江蓠的脂溶性提取物能有效地抑制α-葡萄糖苷酶的活性；褐藻多酚具有明显的抗氧化活性。     

石柑子不同提取部位对RAW264.7细胞炎症的影响

目的：观察石柑子不同提取部位对脂多糖（LPS）诱导的小鼠单核巨噬细胞RAW264.7细胞炎症的影响。方法：用不同质量浓度的石柑子石油醚振摇提取部分、三氯甲烷振摇提取部分、乙酸乙酯振摇提取部分、正丁醇振摇提取部分以及水提取部分和阳性药地塞米松处理LPS刺激的RAW264.7细胞。分别运用噻唑蓝（MTT）法检测细胞活性,RT-qPCR法检测iNOS细胞和COX-2细胞的mRNA表达,Western blot法检测iNOS细胞和COX-2细胞的蛋白表达。结果：石柑子石油醚提取部位、三氯甲烷提取部位、乙酸乙酯提取部位、正丁醇提取部位和水提取部位作用RAW264.7细胞的无毒剂量分别为25、5、10、50、25μg/ml;LPS的用药质量浓度为0.5μg/ml;地塞米松的用药质量浓度为0.4μg/ml;石油醚提取部位25μg/ml和地塞米松能下调iNOS mRNA表达且抑制iNOS的蛋白表达;三氯甲烷提取部位5μg/ml和地塞米松能抑制COX-2的蛋白表达,并且下调COX-2 mRNA的表达。结论：石油醚振摇提取部分和三氯甲烷振摇提取部分对通过LPS诱导的RAW264.7细胞炎症具有抑制作用,其作用机制可能与抑制iNOS和COX-2细胞基因核蛋白的表达有关。     

红藻共附生微生物的分离及抗植物病毒活性筛选

探讨海藻共附微生物的生物活性,从青岛、烟台、威海市海域的两叉蜈蚣藻、舌状蜈蚣藻、蜈蚣藻、附着美叶藻、海萝、江蓠、石化菜中共分离得到38株微生物。采用4种溶剂对发酵液进行平行提取,黄瓜枯萎病菌(Fusarium oxysporum)苹果腐烂病菌(Valsa mali)、番茄绵腐病菌(Pythium aphanidermatum)、番茄灰霉病菌(Botrytis cinerea)为供试菌种,对不同提取物进行抑菌活性测定。结果表明:在浓度为0.005 g/mL时石油醚、乙酸乙酯、乙醇的提取物对四种供试植物病原真菌具有明显的抑菌活性,对黄瓜枯萎病菌的抑菌率均在90%以上;乙醇、乙酸乙酯提取物对番茄灰霉病菌,乙酸乙酯、石油醚提取物对番茄绵腐病菌,均在68%以上。这些结果为海洋植物共附生微生物资源的开发及综合利用奠定了基础。     

六种大型藻浸提液对中肋骨条藻的抑制及活性成分分离

为比较大型藻抑制赤潮藻的能力,研究了孔石莼、羊栖菜、长浒苔、马尾藻、蜈蚣藻和裙带菜的干粉末海水浸提液对中肋骨条藻的化感抑制作用并从长浒苔中分离出具有强抑制作用的组分。分析6种大型藻浸提液对中肋骨条藻的生长抑制率(Inhibitory rate,IR%)和120 h的半效应浓度(Effect concentration,EC50,120 h)发现,孔石莼、羊栖菜、长浒苔、马尾藻和蜈蚣藻的浸提液在浓度达到2.4 g/L时可在实验周期内使中肋骨条藻全部致死,抑制率达到100%,全部致死所需时间分别为96、120、96、144和144 h,当浓度达到4.8 g/L时,6种大型藻均可全部杀死中肋骨条藻,6种大型藻对中肋骨条藻的EC50,120 h分别为1.0、1.0、1.1、1.4、1.5和4.7 g/L。从长浒苔浸提液中分离的乙酸乙酯萃取组分具有强抑藻效果,受试条件下,其EC50值为0.08 mg/L。乙酸乙酯相气相色谱-质谱分析表明,组分至少包含14种物质,其中9-十八炔和邻苯二甲酸二异丁酯是含量最大的2种物质,各物质的抑藻活性尚需进一步研究。长浒苔具有很强的抑藻效果,具有应用于赤潮藻控制的潜力,研究结果为分离鉴定抑制中肋骨条藻的化感物质奠定了基础。     

六种大型藻浸提液对中肋骨条藻的抑制及活性成分分离

为比较大型藻抑制赤潮藻的能力,研究了孔石莼、羊栖菜、长浒苔、马尾藻、蜈蚣藻和裙带菜的干粉末海水浸提液对中肋骨条藻的化感抑制作用并从长浒苔中分离出具有强抑制作用的组分.分析6种大型藻浸提液对中肋骨条藻的生长抑制率(Inhibitory rate,IR％)和120 h的半效应浓度(Effect concentration,EC50,120h)发现,孔石莼、羊柄菜、长浒苔、马尾藻和蜈蚣藻的浸提液在浓度达到2.4 g/L时可在实验周期内使中肋骨条藻全部致死,抑制率达到100％,全部致死所需时间分别为96、120、96、144和144 h,当浓度达到4.8 g/L时,6种大型藻均可全部杀死中肋骨条藻,6种大型藻对中肋骨条藻的EC50、120h分别为1.0、1.0、1.1、1.4、1.5和4.7 g/L.从长浒苔浸提液中分离的乙酸乙酯萃取组分具有强抑藻效果,受试条件下,其EC50值为0.08 mg/L.乙酸乙酯相气相色谱-质谱分析表明,组分至少包含14种物质,其中9-十八炔和邻苯二甲酸二异丁酯是含量最大的2种物质,各物质的抑藻活性尚需进一步研究.长浒苔具有很强的抑藻效果,具有应用于赤潮藻控制的潜力,研究结果为分离鉴定抑制中肋骨条藻的化感物质奠定了基础.     

基于FIA和光学原理的酶传感器检测海水甲基对硫磷

将乙酰胆碱酯酶(acetylcholinesterase,AChE)传感器与流动注射系统(flow injection analysis system,FIA)相结合,通过光学方法测定固定化酶受农药抑制后的残余活性,对海水中微量甲基对硫磷进行定量分析。该系统的适宜工作条件为:温度30℃;固定化酶的用量0.05 U;载液流速0.45 mL/min;进样时间20 min;底物(碘化硫代乙酰胆碱)溶液浓度0.100 mol/L,注射量100μL。在0.1~100μg/L之间,农药浓度的对数值与固定化酶活性的抑制率之间具有良好的线性关系(r=0.995 3)。利用该系统检测含甲基对硫磷分别为0.8μg/L和5.0μg/L的模拟海水样品,获得了较好的准确度和精密度,平均相对误差和变异系数均小于10%。     

Microbial Biomass and Organic Nutrients in the Deep-Sea Sediments of the Central Indian Ocean Basin

In order to assess the impact of deep-sea mining on the in situ benthic life, we measured the microbial standing stock and concentration of organic nutrients in the deep-sea sediments of the Central Indian Ocean Basin in the Indian pioneer area. Sediments were collected using box core and grab samples during September 1996. The total bacterial numbers ranged from 10 10 -10 11 cells per g -1 dry weight sediment. There was a marginal decrease in the number of bacteria from surface to 30 cm depth, though the subsurface section registered a higher number than did the surface. The highest numbers were encountered at depths of 4-8 cm. The retrievable number of bacteria were two orders less in comparison with the direct total counts of bacteria. An almost homogeneous distribution of bacteria, total organic carbon, living biomass, and lipids throughout the depth of cores indicates active microbial and benthic processes in the deep sea sediments. On the other hand, a uniform distribution of total counts of bacteria, carbohydrates, and total organic carbon in all the cores indicates their stable nature and suggests that they can serve as useful parameters for long-term monitoring of the area after the benthic disturbance. Further studies on temporal variability in this region would not only verify the observed norms of distribution of these variables but would also help to understand restabilization processes after the simulated benthic disturbance.     

海上大直径钢管桩打桩过程中桩周土强度弱化研究

海上大直径钢管桩打桩过程中,桩周土体受到强烈扰动而发生强度弱化,掌握桩周土体强度弱化规律对于准确预测打桩过程、保证工程安全具有重要意义。为研究土体强度弱化规律,开展了环剪试验模拟打桩对桩周土体的扰动,测试土体强度随剪切速率的变化规律,建立了描述土体强度弱化规律的拟合公式,引入到打桩分析软件中。研究结果表明：土体的强度折减程度不仅与土体本身的性质有关还受到土体的埋深和剪切速率的影响,埋深越深土体强度折减程度越低,剪切速率越高土体强度折减越高,在打桩分析中可采用这里推荐的线性折减方法来模拟不同深度处土体强度的折减规律。     

Geoacoustic Inversion via Genetic Algorithm and Its Application to Manganese Sediment Identification

An acoustic inversion method using a wide-band signal and two near field receivers is proposed and applied to multiple layered seabed models including a manganese sediment. The inversion problem can be formulated into a probabilistic model comprised of signals, a forward model, and additive noise. The forward model simulates wide-band signals, such as chirp signals, and is chosen to be the source-waveletconvolution plane wave modeling method. The wavelet matching technique, using weighted least-squares fitting, estimates the sediment sound-speed and thickness on which determination of the possible numerical ranges for a priori uniform distribution is based. The genetic algorithm is applied to a global optimization problem to find a maximum a posteriori solution for determined a priori search space. Here the object function is defined by an L 2 norm of the difference between measured and modeled signals. Not only the marginal pdf but also its statistics are calculated by numerical evaluation of integrals using the samples selected during importance sampling process of the genetic algorithm.     

A Review of Some Environmental Issues Affecting Marine Mining

This article reviews information recently available from existing marine and coastal mining for responses to environmental issues affecting marine mining at different depths. It is particularly but not exclusively concerned with those issues affecting seabed biodiversity impact and recovery. Much information has been gathered in the past 10 years from shallow mining operations for construction aggregate, diamonds, and gold, from coastal mines discharging tailings to shallow and deep water, and from experimental deep mining tests. The responses to issues identified are summarized in a series of eight tables intended to facilitate site-specific consideration. Since impacts can spread widely in the surface mixing layer SML, and can affect the biologically productive euphotic zone, the main issues considered arise from the depth of mining relative to the SML of the sea. Where mining is below the SML, the issue is whether it is environmentally better to bring the extraction products to the surface vessel for processing (and waste discharge), or to process the extraction products as much as possible on the seabed. Responses to the issues need to be sitespecific, and dependent on adequate preoperational environmental impact and recovery prediction. For deep tailings disposal from a surface vessel, there are four important environmental unknowns: (1) the possible growth of "marine snow" (bacterial flocs) utilizing the enormous quantities of fine tailings particles (hundreds or thousands of metric tons per day) as nuclei for growth, (2) the possibility that local keystone plankton and nekton species may migrate diurnally down to and beyond the depth of deep discharge and hence be subjected to tailings impact at depth, (3) the burrow-up capability of deep benthos and their ability to survive high rates of tailings deposition, and (4) the pattern and rate of dispersion of a tailings density current through the deep water column from discharge point to seabed. Actions to obtain relevant information in general and site-specifically are suggested.     

Increased Particle Fluxes at the INDEX Site Attributable to Simulated Benthic Disturbance

Particle fluxes were measured 7 m above the sea bottom during the predisturbance, disturbance, and postdisturbance periods by using time series sediment traps attached to seven deep-sea moorings deployed in the INDEX experiment site in the Central Indian Basin. The predisturbance particle fluxes varied between 22.3 to 55.1 mg m -2 day -1 . Increased and variable particle fluxes were recorded by the sediment traps during the disturbance period. The increase observed was 0.5 to 4 times more than the background predisturbance fluxes. The increases in particle fluxes (~4 times) recorded by the sediment trap located in the southwestern direction (DMS-1) were the greatest, which could be the result of preferential movement of resuspended particles generated during the deep-sea benthic disturbance along the general current direction prevailing in this area during the experimental period. Also, the traps located closer to the disturbance area recorded greater fluxes than did the traps far away, across the Deep Sea Sediment Resuspension System path. This variability in recorded particle fluxes by the traps around the disturbance area clearly indicates that physical characteristics such as grain size and density of the resuspended particles produced during the disturbance had an important effect on particle movement. The postdisturbance measurements during ~5 days showed a reduction in particle fluxes of ~50%, indicating rapid particle settlement.     

Determination of In Situ Sediment Shear Strength from Advanced Piston Corer Pullout Forces

The advanced piston corer (APC) has been used by the Ocean Drilling Program since 1985 for recovering soft sediments from the ocean floor. The pullout force measured on extracting the core barrel from the sediment is shown to correlate with the average shear strength of the sediment core measured in the ship's laboratory. A simple rule of thumb is derived relating the shear strength of the sediment to the pullout force. Multiple APC holes at individual sites allow the consistency of the pullout measurements to be assessed. The effects of different operational procedures during APC coring are also explored. Although generally applicable, the correlation between pullout force and laboratory measurements of shear strength breaks down for some APC holes, possibly because of the disturbance of some sediment types during the APC coring process. A better understanding of the physical process of APC coring, and its effect on the properties of the sediment both inside and immediately outside the core barrel, would indicate what confidence can be put on the measurement of pullout force as a way of evaluating the in situ shear strength of deep sea sediments.     

Phylogenetic diversity and phenotypic characterization of cultivable bacterioplankton isolated from polar oceans

A set of 27 marine planktonic bacteria isolated from the polar regions was characterized by 16S rDNA sequencing and physiological and biochemical testing. More than half of these bacteria were positive for caseinase, gelatinase and 13-glucosidase, and could utilize glucose, maltose or malic acid as carbon source for cell growth. Twelve isolates expressed nitrate reduction activities. Except for one antarctic isolate BSwlO175 belonging to Actinobacteria phylum, these isolates were classified as γ-Proteobacteria, suggesting that γ-Proteobacteria dominated in cultivable marine bacterioplankton at both poles. Genus Pseudoalteromonas was the predominant group in the Chukchi Sea and the Bering Sea, and genus ShewaneUa dominated in cultivable bacterioplankton in the Prydz Bay. With sequence similarities above 97%, genus Psychrobacter was found at both poles. These 27 isolates were psychrotolerant, and significant 16S rDNA sequence similarities were found not only between arctic and antarctic marine bacteria （ 〉 99% ）, but also between polar marine bacteria and bacteria from other aquatic environments （ ≥ 98.8% ）, including temperate ocean, deep sea, pond and lake, suggesting that in the polar oceans less temperature-sensitive bacteria may be cosmopolitan and have a bipolar, even global, distribution at the species level.     

Deep-Sea Sediment Compression Curves: Some Controlling Factors, Spurious Overconsolidation, Predictions, and Geophysical Reproduction

Oedometer tests have been carried out on 70 undisturbed surficial clays (at approximately 250 mm below the mudline), mostly collected by free-fall corers from sites widely scattered throughout the deep-sea North Atlantic. Acoustic measurements were also made, initially on contiguous samples and ultimately on the same sample using a geophysically instrumented oedometer which also collected electrical resistivity data. Apart from those quiescent areas below the carbonate compensation depth, such as north of the West Indies where very fine clays exist, most of the samples are silty clays whose geotechnical-geophysical properties are dependent on the type of clay minerals present (and their ability to take in moisture), the sand-size fraction, and the quantity of carbonate present. Thus the pure clays have high compressibilities which decrease on the addition of coarse particles, while the converse is true for the acoustic parameters, these increasing with the sand fraction. Using the notion of the intrinsic compression line for all samples, and comparison to it of the measured compression curves, it is clear that, contrary to some previously held ideas, most deep-sea clays are normally consolidated; the addition of carbonate has the effect of creating an open, stronger sediment skeleton. Interestingly, where information is available, the variation with depth of a sample's acoustic velocity follows the void ratio pressure relationship of the compression curve. This allows the construction of an in-situ sediment compression curve using the in-situ geophysical observations.