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Journal of Ocean University of China 2019年第1期18卷 185-192页

作者： LI Jiaxin ZHANG Pei HONG Liang LIU Chenguang College of Marine Life Sciences Ocean University of China

The extracellular polysaccharide hydrolase-producing strain EP-1 was isolated from seawater and identified as Paenibacillus pabuli. Furthermore, a homogeneous extracellular polysaccharide hydrolase from Paenibacillus pabuli EP-1 was purified by combining ion-exchange chromatography and size exclusion chromatography with a purification fold of 90.69 and recovery of 16.23%. Characterization of the purified polysaccharide hydrolase revealed a molecular mass of 38 k Da and optimum activity at 45℃ and pH 6.0. The polysaccharide hydrolase maintained its stability within a wide range of pH(3.0–12.0) and thermal stability when the temperature was below 50℃. The presence of Hg^(2+), Fe^(2+), Mn^(2+), Co^(2+) and SDS notably decreased hydrolase activity, and organic solvents such as formaldehyde, acetone, DMF and acetonitrile completely inhibited hydrolase activity. The purified hydrolase had no activity on agar, carrageenan, gellan gum, sodium alginate, or starch, but effectively hydrolyzed the polysaccharide from Ulva prolifera. The Km and Vmax values of this hydrolase were 43.84 mg m L^(-1) and 4.33 mg m L^(-1) min^(-1), respectively. The sequence analysis with quantitative time-of-flight mass spectrometry indicated that the hydrolase was an endoglucanase.

关键词： characterization hydrolase polysaccharide purification Ulva prolifera

Physical-biogeochemical interactions and potential effects on phytoplankton and Ulva prolifera in the coastal waters off Qingdao(Yellow Sea, China)

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Acta Oceanologica Sinica 2019年第2期38卷 11-23页

作者： Qinsheng Wei Baodong Wang Qingzhen Yao Zhigang Yu Mingzhu Fu Junchuan Sun Bochao Xu Linping Xie Ming Xin First Institute of Oceanography Ministry of Natural Resources Laboratory for Marine Ecology and Environmental Science Pilot National Laboratory for Marine Science and Technology (Qingdao) Key Laboratory of Marine Chemistry Theory and Technology of Ministry of Education Ocean University of China

In recent years, the spectacular massive green tide of Ulva prolifera has become a recurrent phenomenon appearing every summer in the coastal waters off Qingdao(Yellow Sea, China), attracting the attention of scientists and local government. Based on multidisciplinary data collected during summer and winter, this study focuses on the hydrological characteristics and regional biogeochemical processes in coastal waters off *** results show that the boundary of the Yellow Sea Cold Water Mass(YSCWM) can reach the Qingdao coastal region in summer and is locally raised to the upper layers to form coastal upwelling beyond tidal mixing and favorable wind. The regional summer upwelling off the Qingdao coast effectively enriches the nutrient concentrations in the upper water column and thus promotes growth of phytoplankton but reduces the dissolved oxygen(DO) concentration and pH value in the bottom. The regional summer upwelling off Qingdao coast may facilitate the growth and regional blooming of the U. prolifera that migrate to this region with the southerly ***, the effects of the front on the aggregation of U. prolifera may be significant. In winter, the Yellow Sea Warm Current(YSWC) extends and spreads along the offshore region off the Subei Shoal towards the Qingdao coastal sea. This tongue-shaped warm water meets the cold coastal water off Qingdao, which leads to the formation of a physical front. As a consequence, remarkable fronts of nutrient and chlorophyll a(Chl a) also form between the shoreward warm water and the cold coastal water. This study increases the understanding of the interactions between the regional physical, chemical, and biological processes off the Qingdao coast.

关键词： biogeochemical process upwelling front Ulva prolifera Qingdao coast southern Yellow Sea

Photosynthetic response of floating Ulva prolifera to diurnal changes of in-situ environments on the sea surface

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Journal of Oceanology and Limnology 2019年第2期37卷 589-599页

作者： ZHAO Xinyu TANG Xuexi HU Shunxin ZHONG Yi QU Tongfei WANG Ying College of Marine Life Sciences Ocean University of China Qingdao 266003 China Laboratory for Marine Ecology and Environmental Science Qingdao National Laboratory for Marine Science and Technology Qingdao 266071 China

During yellow sea green tide outbreak, the thalli of Ulva prolifera drifted more than 350 km on the sea surface from off shore of Jiangsu Province to Qingdao city, where they were exposed to complex changes of local environments. The purpose of this study is to investigate the response of the thalli to diurnal changes of environments on the sea surface, and a sea surface environment simulator (SSES) was designed to simulate the natural environment of floating U . prolifera mat. A control experiment is designed in the laboratory, which was processed under suitable conditions (20°C for temperature, 72 μmol photons/(m 2 ·s) for light intensity and 30 for salinity), and an in-situ research was conducted to study the photosynthetic responses of floating U . prolifera to diurnal changes of environments. The results show that the photosynthetic efficiency of the thalli decreased gradually with time, and decreased rapidly after 14:00 local time (LT). After exposed to the environment on the sea surface for 6 h, the photosynthetic activity of the thalli decreased significantly. Furthermore, physiological-level and molecular-level experiments revealed that non-photochemical quenching (NPQ), cyclic electron flow (CEF) and energy redistribution between PSI and PSII all played an important role in the strong photosynthetic plasticity of U . prolifera . NPQ is the most important photoprotective responses to environmental changes before 12:00 LT. The results also confirmed that the CEF and energy redistribution between PSI and PSII are the main synergistic eff ects for the thalli to adapt to the environmental changes when the process NPQ cannot work. And the result can further reveal the reason why U . prolifera can adapt to the living condition of long distance drift on the sea surface. The findings of this research could provide a theoretical basis for explaining outbreaks of the green tide and instructing the management of the problem.

关键词： photosynthetic system floating Ulva prolifera diurnal change photosynthetic plasticity

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

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Journal of Oceanology and Limnology 2019年第4期37卷 1372-1381页

作者： LIU Song LI Bing CHEN Xiaolin QIN Yukun LI Pengcheng CAS Key Laboratory of Experimental Marine Biology Institute of Oceanology Chinese Academy of Sciences Qingdao 266071 China Laboratory for Marine Drugs and Bioproducts Qingdao National Laboratory for Marine Science and Technology Qingdao 266000 China Center for Ocean Mega-Science Chinese Academy of Sciences Qingdao 266000 China Marine Science and Engineering College Qingdao Agriculture University Qingdao 266000 China

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.

关键词： polysaccharides Enteromorpha prolifera maize seedling NaCl stress

Selenylation Modification of Degraded Polysaccharide from Enteromorpha prolifera and Its Biological Activities

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Journal of Ocean University of China 2018年第2期17卷 445-450页

作者： LV Haitao DUAN Ke SHAN Hu College of Chemistry and Pharmaceutical Sciences Qingdao Agricultural University College of Animal Science and Technology Qingdao Agricultural University

Polysaccharide extracted from Enteromorpha prolifera possessed excellent biological activities,but its molecular weight was greatly high which influenced the *** Se had higher biological activities and was safer than inorganic Se *** the present study,Enteromorpha polysaccharide was degraded to low molecular weight by free-radical degradation method of H_2O_2 and ascorbic *** single factor and orthogonal experiments,the optimal degradation conditions were reaction time of 2 h,reaction temperature of 50℃,H_2O_2/ascorbic acid(n/n=1:1)concentration of 15 mmol L^(-1),and solid-liquid ratio of 1:50(g mL^(-1)).Then,the degraded polysaccharide was chemically modified to obtain its selenide derivatives by nitric acid-sodium selenite *** selenium content was 1137.29μg g^(-1),while the content of sulfate radical had no *** spectra indicated that the selenite ester group was *** polysaccharide selenide was characterized and evaluated for antioxidant,antifungal and antibacterial *** results showed that degraded polysaccharide selenide had strong capacity of scavenging DPPH and·OH free *** had significant antibacterial properties for Escherichia coli,Bacillus subtilis and Salmonella spp.,and it also had significant antifungal properties for Apple *** result ascertained degradation and selenylation modification did not change the main structure of *** was possible that free-radical degradation was an effective way for enhancing antioxidant activity to decrease molecular weight of polysaccharides.

关键词： Enteromorpha prolifera polysaccharide free-radical degradation selenylation modification biological activity

Isolation, Expression and Characterization of rbc L Gene from Ulva prolifera J. Agardh(Ulvophyceae, Chlorophyta)

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Journal of Ocean University of China 2015年第6期14卷 1087-1095页

作者： SHAO Zhanru LI Wei GUO Hui DUAN Delin Institute of Oceanology Chinese Academy of Sciences Institute of General Botany and Plant Physiology Friedrich Schiller University University of Chinese Academy of Sciences

Ulva prolifera is a typical green alga in subtidal areas and can grow tremendously fast. A highly efficient Rubisco enzyme which is encoded by Up Rbc L gene may contribute to the rapid growth. In this study, the full-length Up Rbc L open reading frame(ORF) was identified, which encoded a protein of 474 amino acids. Phylogenetic analysis of Up Rbc L sequences revealed that Chlorophyta had a closer genetic relationship with higher plants than with Rhodophyta and Phaeophyta. The two distinct residues(aa11 and aa91) were presumed to be unique for Rubisco catalytic activity. The predicted three-dimensional structure showed that one α/β-barrel existed in the C-terminal region, and the sites for Mg^(2+)coordination and CO_2 fixation were also located in this region. Gene expression profile indicated that Up Rbc L was expressed at a higher level under light exposure than in darkness. When the culture temperature reached 35℃, the expression level of Up Rbc L was 2.5-fold lower than at 15℃, and the carboxylase activity exhibited 13.8-fold decrease. Up Rbc L was heterologously expressed in E. coli and was purified by Ni^(2+) affinity chromatography. The physiological and biochemical characterization of recombinant Rubisco will be explored in the future.

关键词： Ribulose-1,5-bisphosphate carboxylase/oxygenase large subunit sequence analysis real-time PCR in vitro expres-sion Ulva prolifera

Adsorption of Reactive Dyes on Activated Carbon Developed from <i>Enteromorpha prolifera</i>

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American Journal of Analytical Chemistry 2013年第7期4卷 17-26页

作者： Deshuai Sun Zhongyi Zhang Mengling Wang Yude Wu College of Chemistry & Chemical Engineering Qingdao University Qingdao China Qingdao Sub-Administration Administrative Departments for Yellow River Diversion to Qingdao Project of Shandong Province Qingdao China

Activated carbon was prepared from Enteromorpha prolifera by zinc chloride activation. The adsorption behaviors of three reactive dyes (Reactive Red 23, Reactive Blue 171 and Reactive Blue 4) onto this biomass activated carbon were investigated in batch systems. The experimental findings showed that the removal efficiencies of three dyes onto activated carbon were maximum at the initial solution pH of 4.5 - 6.0. Thermodynamic studies suggested that adsorption reaction was an endothermic and spontaneous process. Adsorption isotherm of the three dyes obeyed Freundlich isotherm modal. Dye adsorption capacities of activated carbon were 59.88, 71.94 and 131.93 mg·g?1 for RR23, RB171 and RB4 at 27?C, respectively. Second-order kinetic models fitted better to the equilibrium data of three dyes. The adsorption process on activated carbon was mainly controlled by intraparticle diffusion mechanism.

关键词： Activated Carbon Enteromorpha prolifera Reactive Dye Adsorption Isotherm Adsorption Dynamics

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青岛海域大面积聚集漂浮浒苔的显微观测

海洋科学 2008年第8期32卷 30-33页

作者：牛建峰范晓蕾潘光华朱大玲谢嘉琳刘伟王广策孙松周百成中国科学院海洋研究所山东青岛266071

对近期在青岛海域大面积聚集漂浮的浒苔(Enteromorpha prolifera(Muell)***.)进行常规显微镜观察,发现细胞内存在大小约1μm的可动的颗粒状结构。分别采用鞭毛染色和扫描电镜观察的方法对其进行了初步研究,均未发现此颗粒状可动结构具... 详细信息

对近期在青岛海域大面积聚集漂浮的浒苔(Enteromorpha prolifera(Muell)***.)进行常规显微镜观察,发现细胞内存在大小约1μm的可动的颗粒状结构。分别采用鞭毛染色和扫描电镜观察的方法对其进行了初步研究,均未发现此颗粒状可动结构具有鞭毛。用透射电镜对浒苔细胞的超微结构特征进行了观察,显示浒苔细胞壁致密而厚,每个浒苔细胞有1个片状叶绿体,贴近于细胞壁分布,淀粉粒含量丰富,但依然未发现胞内颗粒状结构具有鞭毛。

关键词：浒苔(Enteromorpha prolifera (Muell)J.Ag) 鞭毛染色内部结构扫描电子显微镜透射电子显微镜

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浒苔多糖对羟自由基的清除作用研究

海洋科学 2010年第1期34卷 44-47页

作者：薛丁萍魏玉西刘淇刘蕾青岛大学生物系山东青岛266071 中国水产科学研究院黄海水产研究所山东青岛266071

研究确定了Fenten(水杨酸法)反应所需水杨酸、H2O2和Fe2+的浓度,并用水杨酸法对浒苔(Entero-morpha prolifera)水提多糖及其酸提多糖对羟自由基的清除能力进行了测定,同时,与合成抗氧化剂BHT和TBHQ进行对比。结果表明,浒苔水提多糖及酸... 详细信息

研究确定了Fenten(水杨酸法)反应所需水杨酸、H2O2和Fe2+的浓度,并用水杨酸法对浒苔(Entero-morpha prolifera)水提多糖及其酸提多糖对羟自由基的清除能力进行了测定,同时,与合成抗氧化剂BHT和TBHQ进行对比。结果表明,浒苔水提多糖及酸提多糖对羟自由基均有一定的清除效果,且清除率与浓度存在剂量依赖关系,酸提多糖对羟自由基的清除能力大于水提多糖。在较高质量浓度(>1.2 g/L)时酸提多糖对羟自由基的清除能力是水提多糖的2倍。

关键词：浒苔( Enteromorpha prolifera ) 多糖羟自由基清除率

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浒苔化学成分研究

中国海洋大学学报（自然科学版） 2010年第5期40卷 93-95页

作者：张金荣唐旭利李国强中国海洋大学医药学院海洋药物教育部重点实验室山东青岛266003 中国海洋大学化学化工学院山东青岛266003

利用硅胶柱色谱、Sephadex LH-20柱色谱和HPLC等手段,从浒苔Entermorpha prolifera的甲醇提取物中分离得到了5个单体化合物。它们的结构通过波谱分析结合文献对照被鉴定为：胆甾醇（1）,13^2S-羟基脱镁叶绿素a（2）,13^2R-羟基脱镁叶绿... 详细信息

利用硅胶柱色谱、Sephadex LH-20柱色谱和HPLC等手段,从浒苔Entermorpha prolifera的甲醇提取物中分离得到了5个单体化合物。它们的结构通过波谱分析结合文献对照被鉴定为：胆甾醇（1）,13^2S-羟基脱镁叶绿素a（2）,13^2R-羟基脱镁叶绿素a（3）,13^2S-羟基脱镁叶绿素b（4）,phaeophytin a hydroperoxide（5）。化合物2-5均为首次从该种海藻中分离得到。

关键词：浒苔化学成分 Entermorpha prolifera 结构鉴定