海洋细菌QY202产κ-卡拉胶酶的分离纯化和性质研究

为获得高效降解卡拉胶菌株,从青岛太平角海域采集的角叉菜表面分离到1株高产κ-卡拉胶酶的海洋交替假单胞菌(Pseudoalteromonas sp.)QY202,经硫酸铵沉淀、脱盐、DEAE阴离子交换层析等步骤从该菌株发酵液上清中分离纯化得到1种专一性降解κ-卡拉胶的κ-卡拉胶酶,并研究了该酶的基本酶学性质.结果表明该酶被纯化了23.1倍,回收率为43.9%,分子量大小为33.2 kDa.酶的最适反应温度为40 ℃,最适反应pH为8.0,在0～40 ℃,pH=7.0～8.0之间酶活力较稳定.酶对底物κ-卡拉胶的米氏常数Km值为1.6 mg/mL.Na~+、K~+对酶活有促进作用,而Hg~(2+)、Cu~(2+)强烈抑制酶的活性.酶解κ-卡拉胶的主产物为硫酸新κ-卡拉二糖和硫酸新κ-卡拉四糖.     

异枝麒麟菜硫酸多糖的降解及其对尿石矿物草酸钙的抑制作用

采用过氧化氢法降解了相对分子质量约为141万±8.3万的海藻异枝麒麟菜(Eucheuma striatum Schmitz)硫酸多糖(ESPS),降解产物平均相对分子质量为4 819±440.降解后多糖的硫酸基(OSO2-3)质量分数稍有下降,由16.03%降至15.20%左右.同时,用体外模拟方法研究了降解前后ESPS对草酸钙(CaOxa)晶体生长的抑制作用,降解后的ESPS明显优于未降解多糖,其诱导生成的一水草酸钙(COM)晶体尺寸进一步减小,晶体数量减少,且棱角更为圆钝.表明低分子质量ESPS更能抑制CaOxa晶体的成核和生长.     

褐藻多糖的药理作用与制备

阐述了褐藻糖胶的化学组成和结构。从褐藻中提取分离得到的褐藻糖胶具有显著的抗癌、抗凝、降脂、免疫调节和抗衰老作用,既可作为保健食品,也可作为治疗药物。目前,我国制备褐藻糖胶,主要采用60%乙醇沉淀法和CPC沉淀法从海带水碱凝沉物中提取,或用稀酸直接从海带中提取,并用乙醇分级法和色谱法对褐藻糖胶进行纯化。     

基于 R-藻红蛋白及硫酸多糖提取的次等紫菜综合利用技术

末水条斑紫菜以组织捣碎机粉碎,在10 mmol/L磷酸盐缓冲液(p H 6.8)中反复冻融3次,收集上清液,通过膨化床疏水层析技术分离R-藻红蛋白(R-PE),剩余残渣用于硫酸多糖提取。使用膨化柱分离,粗提液中约17%的藻红蛋白可以被回收,DEAE-Sepharose离子交换树脂纯化后,约12%的R-藻红蛋白得到回收,光谱纯度大于3.2,纯化得率为0.66 mg/g鲜紫菜。吸收光谱、荧光发射光谱以及凝胶电泳均显示该藻红蛋白属于典型三峰型R-藻红蛋白。利用藻红蛋白提取后的残渣,每克条斑紫菜可回收到30.5 mg的粗多糖,其中硫酸基含量为21.8%。实验证明,微波辅助抽提与热水浸提对硫酸多糖得率无显著影响。纯化的R-藻红蛋白与紫菜硫酸多糖可用于食品、化妆品添加,或药品、保健品的开发。本文对探索次等紫菜生物质的综合、高值化利用,进一步促进我国相关产品的开发与应用具有重要意义。     

黄、东海春季海水胞外酶活性水平分布特征研究

海水胞外酶活性可以指示有机物的分布特征以及微生物的营养状况。我们测定了2017年3月25日至4月15日黄海和东海44个大面站以及2018年4月28日至29日胶州湾湾口附近海域10个站位表层海水中的8种胞外酶活性并研究了其分布特征。2017年春季黄、东海表层海水中碱性磷酸酶和脂肪酶活性较高,高值区出现在苏北沿岸和南黄海中部,碱性磷酸酶与磷酸盐浓度之间呈正相关。其余6种酶(肽酶、几丁质酶、纤维素酶、α-D-葡萄糖苷酶、β-D-半乳糖苷酶、木糖苷酶)活性高值区出现在长江口以东的外海,东海的β-D-半乳糖苷酶、木糖苷酶平均酶活性显著高于黄海。8种酶活性平均值排列顺序由大到小为:碱性磷酸酶、脂肪酶、肽酶、几丁质酶、α-D-葡萄糖苷酶、β-D-半乳糖苷酶、纤维素酶、木糖苷酶,其中α-D-葡萄糖苷酶和β-D-半乳糖苷酶的活性基本一致。2018年春季胶州湾附近海域海水中碱性磷酸酶、脂肪酶、木糖苷酶活性分布为近岸高于远岸,几丁质酶活性为近岸低于远岸。8种酶活性平均值排列顺序由大到小为:碱性磷酸酶、脂肪酶、肽酶、木糖苷酶、α-D-葡萄糖苷酶、β-D-半乳糖苷酶、几丁质酶、纤维素酶,其中几丁质酶和纤维素酶的...     

壳聚糖的化学改性及其产物的红外解析研究

甲壳素是一种天然高分子多糖，具有与纤维素相近的骨架结构，其资源丰富，用途广泛(方波，1998)。但由于分子内和分子间存在很强的氢键作用力，因而不能熔融，也不溶于普通溶剂(如水、乙醇等)(董炎明等，2002)，实际应用中较多的是其部分或全部脱乙酰化产物——壳聚糖。壳聚糖虽然可以溶于酸性水溶液，但不能直接溶于水中，且在酸性水溶液中不稳定，也不溶于一般的有机溶剂，这在很大程度上限制了它的应用(董炎明等，2002)。所以，水溶性壳聚糖衍生物的研制正成为一个新的研究方向。壳聚糖分子中C2位上的-NH2，C3、C6位上的-OH，均具有较强的反应活性，在适当条件下可进行多种化学修饰，如酰基化、羧烷基化、硫酸酯化、烷基化、羟烷基化及氰烷基化等。引入上述功能性基团，可增加壳聚糖的溶解性和功能性，拓宽了壳聚糖的应用范围。这些衍生物的制备研究已成为壳聚糖应用开发的主要方向之一。     

免疫多糖对中国对虾血清溶菌酶、磷酸酶和过氧化物酶的作用

于１９９７年９月在青岛红鸟养殖场采集中国对虾,给对虾腹腔注射不同剂量的海藻多糖和北虫草我糖后,用生化法测定其血清中的溶菌酶,碱性磷酸酶,酸性磷酸酶和过氧化物酶活性的动力学变化。结果表明,注射１．０％北虫草多糖及１．０％海藻多糖４８ｈ后,对虾血清中的ＬＳＺ活性由对照组的０．２５Ｕ／ｍｌ分别增至０．８８Ｕ／ｍｌ和０．７５Ｕ／ｍｌＰＯＤ活性由对照组的０．１１Ｕ／ｍｇ分别增至２．２Ｕ／ｍｇ和１．９６Ｕ／ｍ     

Effect of polysaccharide from Enteromorpha prolifera on maize seedlings under NaCl stress

In this study, a polysaccharide from Enteromorpha prolifera (EP) was extracted and its effect on maize seedlings under NaCl stress was investigated. Firstly, the components and structure of the EP were determined. We found that EP is a sulfated polysaccharide of high-molecular weight (Mw, 1 840 KDa) heteropolysaccharides and the main monosaccharide is rhamnose. The polysaccharide was applied to explore its effect on the growth of maize seedlings and its defense response under a salt stress. The results show that EP could promote the growth of maize seedlings under the salt stress. In addition, EP was shown able to significantly regulate membrane permeability and adjustment of osmotic substances such as soluble protein, soluble sugar, and proline, antioxidant enzymes containing superoxide dismutase, catalase, peroxidase, and ascorbate peroxidase. Therefore, EP is an effective salt-resistant substance for the growth of maize seedlings under NaCl stress.     

产新琼四糖的海洋微泡菌属AG1热稳定性β-琼胶酶的过量表达与鉴定

从微泡菌属AG1（Microbulbifer sp. AG1）克隆得到1302 bp大小的琼胶酶基因,该基因编码产物为一个成熟蛋白（413个氨基酸残基）外加一个信号肽（20个残基）。将不含信号肽片段的琼胶酶在E. coli BL21 （DE3）中进行了异源表达和纯化。使用琼脂糖作为底物,该重组琼胶酶的最适反应温度和pH分别为60℃和7.5。该重组酶表现出优良的热稳定性,在50℃和60℃下处理1 h,重组琼胶酶仍能分别保持67%和19%的残余酶活力。除了SDS,重组琼胶酶对于其他测试的抑制剂、去垢剂和尿素变性剂有着较好的抗性。利用薄层色谱和以对硝基苯-α/β-D-吡喃半乳糖苷为底物的酶活力分析结果表明,该重组琼胶酶为β型琼胶酶,它水解琼脂糖的主要终产物为新琼四糖,而且不同聚合度的酶解产物具有抗氧化活性。     

海洋硫酸多糖916在2种酶作用下稳定性的研究

利用高效凝胶渗透色谱法(HPGPC)和明胶比浊法研究了海洋硫酸多糖916在溶菌酶和胰蛋白酶作用下的稳定性，分别考察了酶作用下916的重均分子量、分子量分布系数和游离硫酸根含量的变化。结果表明：在所选定的实验条件下，916的重均分子量、分子量分布系数和游离硫酸根含量均未发生显著变化，表明在所选择的实验条件下916对溶菌酶和胰蛋白酶是稳定的。     

The effects of fucoidans from Laminaria japonica on AAPH mediated oxidation of human low-density lipoprotein

1Introduction Thegeneration,reactionandconsequenceof freeradicalsinbiologicalsystemshavereceived muchattentionrecentlyinconnectionwithavariety ofpathologicalevents(BarryandSusanna,1993;FangandLi,1999).LDLoxidizedbyexposureto tracemetalionsCu2 andFe3 (Hein…     

Urbanised beaches of the Ligurian coastal area (NW Mediterranean): A classification based on organic-matter characteristics and hydrolytic enzymatic activities

The beaches of Liguria have been intensively affected by human activities for over a century, transforming nearly the entire coastline from natural to urbanised and significantly upsetting beach ecological properties. The present study aims to investigate 9 Ligurian beaches characterised by different degree of urbanisation, to test if and to what extent the organic-matter (OM) recycling processes can be linked to the human activity. Swash zone sediment, sampled during the spring–summer–autumn period, when the anthropogenic influence is at its maximum due to tourism, was analysed for OM features and recycling processes. Multivariate statistical analyses showed that huge amounts of detrital OM accumulated in the more urbanised sites, where the anthropogenic influence was at its peak, deriving from higher inhabitant number and density, from the presence of crowded roads very near to the swash zone and sewage treatment plants. The presence of torrent outlets on the beaches provided further OM accumulation. Lipids, carbohydrates and degraded autotrophic pigments were the OM fractions mainly responsible of the differentiation, and rather constant, high labile phosphorus contents were found in the more urbanised sites. The high activity values of the hydrolytic enzymes indicate the response of the microbial system to the OM accumulation in the urban sites. However, a decoupling of the trends of some enzymatic activities (namely glucosidase and lipase) and their target OM was observed in the highly urbanised conditions.     

Crude oil bioremediation in sub-Antarctic intertidal sediments: chemistry and toxicity of oiled residues

The effectiveness of fertilizers for crude oil bioremediation in sub-Antarctic intertidal sediments was tested over a one-year period in a series of ten (10) experimental enclosures. Chemical, microbial and toxicological parameters demonstrated the effectiveness of various fertilizers in a pristine environment where hydrocarbon degrading bacteria (HDB) had not been stimulated by previous accidental spills or human activities. The low temperature of seawater (3-4 degrees C) had no obvious effects on the HDB community and the bioremediation process. Over 90% of n-alkanes were degraded in the first six months and most light aromatics (2-3 rings) disappeared during the first year of observation. The toxicity of oiled residues (Microtox(R) SP) was significantly reduced in the first 6 months of the process, but it increased again in the last months of the experiment. One of the fertilizers containing fishbone compost enriched with urea, inorganic phosphorus and a lipidic surfactant reduced significantly the toxicity of oil residues in the last 3 months of the experiment. Interstitial waters collected below the oil slicks during the remediation showed no toxicity, and even stimulated Vibrio fischeri. When comparing all fertilizers to the control plots, a good correlation (r(2)=0.82) was found between the growth rate of HDB and the degradation rate of n-alkanes in the first 90 days of the experiment only indicating that fertilizers were efficient for at least 3 months but their beneficial effects were lost after 6 months.     

Distribution of moretene, sterere, fernene, hopene and dienoic carboxylic acid in marine sediments in sea area of the Southern Ocean

The soluble organic matters were extracted from marine sediments in the sea area of Southern Ocean by using organic solvents. The hydrocarbon and carboxylic acid fractions were separated with the thin layer chromatography. The organic compounds of 170(H), 21α(H)- bishomomoretene, cholest - 5 - ene, 24 - methyl - cholestene, 24 - ethylcholestene, hop-17(21)-ene, neohop - 13(18)-ene, fern-8-ene, fern-7-ene, 170(H), 210 (H) - hop - 22(29)-ene (diplotene), steranes, β, β-hopanes C29 -C31 and unsaturated carboxylic acids C18:2Δ9.12 , C18:1Δ9,C18:1Δ11 , have been identi-fied in the hydrocarbon and carboxylic acid fractions by means of gas chromatography and gas chromatography - mass spec-trometry - data system. The distributions of 3, a - bishomomoretene, β,β- hopene and β,β- hopane are characteristic of immature organic matter. The sterane, C29 20S/20R epimer ratio 0. 6 indicate that the organic matter had experienced a thermal evolution in the early sedimentation. The unsaturated fatty acids espec     

Enhanced carbohydrate production by Southern Ocean phytoplankton in response to in situ iron fertilization

Storage carbohydrates (e.g., water-extractable β-1,3-d-glucan in diatoms) are of key importance for phytoplankton growth in a variable light climate, because they facilitate continued growth of the cells in darkness by providing energy and carbon skeletons for protein synthesis. Here, we tested the hypothesis that synthesis of storage carbohydrates by phytoplankton in the Southern Ocean is reduced by low iron and light availability. During the EisenEx/CARbon dioxide Uptake by the Southern Ocean (CARUSO) in situ iron enrichment experiment in the Atlantic sector of the Southern Ocean in November 2000, we studied the dynamics of water-extractable carbohydrates in the particulate fraction over the period of 3 weeks following the iron release. The areal amount (integral between 0- and 100-m depth) of carbohydrates increased from 1400 to 2300 mg m⁻² inside the iron-enriched patch, while remaining roughly constant in the surrounding waters. Most of the increase inside the patch was associated with the fraction of large (>10 μm) phytoplankton cells, consistent with the shift in the community structure towards larger diatoms. Deck incubations at 60% of the ambient irradiance revealed that the diurnal chlorophyll a (Chl a)-specific production rates of water-extractable polysaccharides were significantly higher for “in-patch” than for “out-patch” samples (0.5 vs. 0.3 μg C [μg Chl a]⁻¹ h⁻¹, respectively). Together with the higher photochemical efficiency of photosystem II (F_v/F_m), this indicates enhanced photosynthetic performance in response to iron fertilization. In addition, the nocturnal polysaccharide consumption rates were also enhanced by iron release, causing a striking increase in the diel dynamics of polysaccharide concentration. An iron-stimulated increase in diel dynamics was also observed in the fluorescence and size of pico- and nanophytoplankton cells (measured by flow cytometry) and is indicative of enhanced phytoplankton growth. Diurnal polysaccharide production by phytoplankton inside the patch was light-limited when they were incubated at intensities below ca. 200 μmol m⁻² s⁻¹ (daytime average). These irradiance levels correspond to those at 20- to 30-m depth in situ, whereas the upper mixed layer was frequently several-fold deeper due to storms. Therefore, these first measurements of phytoplankton carbohydrates during an in situ iron release experiment have revealed that both light and iron availability are the key factors controlling the synthesis of storage carbohydrates in phytoplankton and, hence, the development of diatom blooms in the Southern Ocean.     

安络小皮伞［Marasmius androsaceus （L：Fr）Fr］中水溶性多糖的研究Ⅳ总糖及糖蛋白的分布、分级与测定

用水提取的安络小皮伞的多糖．经醇析．真空干燥后，用ｓｅｐｈａｒｏｓｅ４Ｂ柱层析，酚一Ｈ２ＳＯ４法检测其多糖分布，紫外吸收法（２８０ｎｎ）检测其蛋白质分布，表明提取物为多糖和糖蛋白的混合物，总糖含量为３０．５％。ｌｏｒｒｙ法和克氏定氮法测定蛋白质含量１５％。采用Ｐ．Ｃ和Ｇ．Ｃ法测定，结果提取物中的多糖由三种中性单糖组成．其摩尔比为：ＧＬＣ：Ｍａｎ，ＦＵＣ＝１．２：３：１．７。用Ｆｅｈｌｉｎｇ试剂法测定，表明混合物中有甘露聚精。Ｆｅｌｌｌｉｎｇ试剂法与甲醇、乙醇分级法相结合，从提取物中分出六个糖蛋白级分：Ｆｐ１、Ｆｐ２、Ｆｓ１、Ｆｓ２、Ｆｓ３和Ｆｓ４，其中Ｆｐ１、Ｆｓ１和Ｆｓ３经ｓｅｐｈａｒｏｓｅ４Ｂ柱测定为多糖分子量单一的级分。     

Investigation of the carrageenans extracted from Solieria filiformis and Agardhiella subulata from Mar Piccolo, Taranto

Dried samples of the red algae Solieria filiformis and Agardhiella subulata from Mar Piccolo, Taranto, were extracted by stirring in water at 25 (Cold), 85 (Hot) and 120 (pressure) °C. For each species, six successive cold, three hot and two pressure extractions were performed and analyzed separately. Water-soluble polysaccharides were isolated after treatment with amylase, alcohol precipitation, dialysis and freeze drying. The total, starch-free yields were 27 and 24% of the dry weight for S. filiformis (SF) and A. subulata (AS), respectively. FTIR and NMR spectroscopic analysis showed that the different cold and hot water extracts had a similar structural backbone, which can be characteristic of gelling type carrageenans with a dominant iota repeating structure (DA2S-G4S). However, some irregularities were detected by NMR, which may be attributed to 6-sulphated 4-linked precursor units. The occurrence of such and other irregularities was more frequent in the SF samples, giving a possible explanation for the enhanced extractability in cold water of carrageenan polymers from this species.     

凡纳滨对虾P23蛋白基因的筛选、表达和生物信息学分析

克隆凡纳滨对虾极端体重个体的组织差异表达基因P23基因并进行生物信息学分析, 为进一步研究该基因的功能以及凡纳滨对虾的分子选育等研究提供信息。以凡纳滨对虾雌虾极端体重个体腹部肌肉为实验材料, 利用抑制消减杂交(SSH)技术构建极大体重雌性个体和极小体重雌性个体腹部肌肉组织正反向消减cDNA文库:正库(以极大体重个体为试验组, 以极小体重个体为驱动组, L-S)和反库(以极小体重个体为试验组, 以极大体重个体为驱动组, S-L)消减cDNA文库, 并采用实时定量技术分析P23基因的组织表达规律, 利用生物信息学对其功能和结构进行预测。以β-actin为看家基因检测两个文库的消减效率分别为210和25, 实时定量技术分析结果表明P23基因在体重的调节中起上调作用。P23基因编码区序列全长495bp, 编码165个氨基酸, GenBank登录号:JF806619。生物信息学分析发现P23蛋白部分序列含有强疏水性, 无跨膜螺旋结构, 两种信号肽预测都显示P23含有信号肽。     

An evaluation of a C-18 solid phase extraction technique for isolating metal-organic complexes from central North Pacific Ocean waters

This paper presents results from an investigation using a C-18 solid phase extraction (SPE) method for isolating dissolved metal-organic complexes from seawater. The vertical distribution of dissolved organically complexed copper isolated by this technique in the intermediate and deep waters of the central North Pacific is similar to that observed in the North Atlantic. Copper isolated by C-18 SPE from 125 to 5000 m in the North Pacific ranged from 11 to 30% of the total dissolved copper, whereas published concentrations for similar depths in the North Atlantic ranged from 22 to 36% of the total dissolved copper. Evidence from voltammetric studies suggests that the C-18 SPE technique may isolate the major portion of the organically complexed copper from deep waters.In oceanic surface waters, however, a major discrepancy exists — recent voltammetric and equilibration studies indicate that essentially all of the dissolved copper and zinc is associated with organic complexes, while the C-18 SPE method isolates <10% of the total dissolved copper and zinc in the North Pacific and <40% of the total dissolved copper in the North Atlantic. Thus, in surface waters, it appears that the major fraction of organically complexed copper and zinc is not isolated by the C-18 SPE approach.The fractions of total dissolved cadmium, iron, manganese, and nickel isolated by the C-18 SPE technique were also studied. The degree to which each of these metals is complexed with the fraction of the dissolved organic matter isolated by this method is smaller and not as significant as that observed for copper. These results do not imply, however, that organic complexation of these metals is not significant, only that the organic—metal complexes are not isolated by the C-18 SPE method.