SCREENING FOR ANTIBACTERIAL AND ANTIFUNGAL ACTIVITIES IN SOME MARINE ALGAE FROM THE FUJIAN COAST OF CHINA WITH THREE DIFFERENT SOLVENTS

Three different solvents viz ethanol, acetone and methanol-toluene (3:1) were used to extract antibiotics from 23 species of marine algae belonging to the Chlomphyta, Phaeophyta and Rhodophyta. Their crude extracts were tested for antibacterial and antifungal activities. Among them, the ethanol extract showed the strongest activity against the bacteria and fungi tested. Four species of the Rhodophyta (Laurenc/a okamurai, Dasya scoparia, Grateloupia filicina and plocamium telfairiae ) showed a wide spectrum of antibacterial activity. Every solvent extract from the four species was active against all the bacteria tested. The test bacterium Pseudomonas solancearum and the fungus Penicilium citrinum were most sensitive to the extracts of marine algae. In general, the extracts of seaweeds inhibited bacteria more strongly than fungi and species of the Rhodophyta showed the greatest activity against the bacteria and fungi tested.     

The effect of nitric oxide on the growth of marine phytoplankton

The incubation experiments of Skeletonema costatum, Dicrateria zhanjiangensis nov. sp., and Platymonas sub-cordiformis, and those of Emiliania huxleyi were carried out in the Marine Physical Chemistry Laboratory in Ocean University of China and in the Marine Organic Geochemistry Laboratory in the University of Georgia respectively. Nitric oxide was added into the media when these marine microalgae were growing. We found the growth of these four microalgae were promoted or inhibited when nitric oxide of different concentrations was added one or two times each day during the cultivation process. The results are consistent with the influence of nitric oxide on the growth of high plants. The results show that nitric oxide may be a new factor of regulation and control for the phytoplankton growth in seawater.     

Antifouling activities of marine bacteria associated with sponge (Sigmadocia sp.)

The present study aimed at assessing the antifouling activity of bacteria associated with marine sponges. A total of eight bacterial strains were isolated from the surface of sponge Sigmadocia sp., of them, SS02, SS05 and SS06 showed inhibitory activity against biofilm-forming bacteria. The extracts of these 3 strains considerably affected the extracellular polymeric substance producing ability and adhesion of biofilm-forming bacterial strains. In addition to disc diffusion assay, microalgal settlement assay was carried out with the extracts mixed with polyurethane wood polish and coated onto stainless steel coupons. The extract of strain SS05 showed strong microalgal settlement inhibitory activity. Strain SS05 was identified as Bacillus cereus based on its 16S rRNA gene. Metabolites of the bacterial strains associated with marine invertebrates promise to be developed into environment-friendly antifouling agents.     

Comparative studies of inorganic carbon utilization inEmiliania huxleyi and some non-calcifying marine microalgae

Inorganic carbon utilization in the non-calcifying marine microalgae,Nannochloropsis oculata, Phaeodactylum tricornutum andPorphyridium purpureum was compared with high- and low-calcifying strains ofEmiliania huxleyi grown in artificial seawater medium aerated with either air (0.03% V/V CO₂) or CO₂-free air. For high-calcifying strain ofE. oculata andP. tricornutem, similar growth patterns were observed in air-and CO₂-free air-grown cultures.P. purpureum showed a less final cell density in CO₂-free air than in air-grown culture. However, low-calcifying strain ofE. huxleyi was able to grow only in air-grown culture, but not in CO₂-free air-grown culture. Measurements of alkalinity, pH, concentration of dissolved inorganic carbon (DIC) and free CO₂ showed different patterns of DIC utilization. WithN. oculata, P. tricornutum andP. purpureum the pattern of DIC utilization was characterized by an increase of pH and a decrease of DIC but a constant alkalinity in the cultures aerated with air or CO₂-free air, suggesting that bicarbonate utilization was concomitant with an efflux of OH⁻. Both alkalinity and pH were maintained rather constant in air-grown culture of low-calcifying strain ofE. huxleyi, suggesting that diffusive entry of CO₂ could meet the requirement of DIC for its photosynthesis and growth. High-calcifying strain ofE. huxleyi, however, showed a pattern of decrease of alkalinity and DIC but an almost constant pH, indicating that bicarbonate was the major form of inorganic carbon utilised by this organism and bicarbonate uptake is unlikely to be accompanied by an efflux of OH⁻. The final pH values reached byN. oculata, P. tricornutum andP. purpureum in a closed system were 10.75, 10.60 and 9.85 respectively, showing that bicarbonate utilisation is concomitant with an efflux of OH⁻. While the final pH of 8.4 in high-calcifyingE. huxleyi suggests that bicarbonate utilization was not accompanied by an efflux of OH⁻. Contribution No. 3557 from the Institue of Oceanology, Chinese Academy of Sciences. This work was supported by NERC grant GRE3/7853 U. K. and partly supported by Bio-Engineering Center, SSTC 96-C01-05-01.     

赤魟尾刺提取物的抗肿瘤作用

<正>赤魟Dasyatis akajei(Muller&henle)隶属于软骨鱼纲,下孔总目,鲼形目,魟科,魟属,常栖息于底质为泥沙的深潭中[1-3]。赤魟肉性味甘、咸平,有补气之功效。用其熬油,主治小儿疳积。尾刺研末入药,对治疗胃癌、食道癌、肺癌、乳腺炎、咽喉炎、疟疾、牙痛、魟鱼尾刺刺伤均有一定疗效[4]。赤魟尾刺含有多种毒素,有重要药理作用。涂洪斌等克隆出编码赤魟肿瘤抑制因子IPL的全长cDNA序列[5],并报道了赤魟亲环素A的融合表达、纯化及活性特征[6]。目前,赤魟尾刺的生物活性成分及其相关毒理和药理作用仍不清楚[7]。笔者研究了赤魟尾刺提取物(extracts of caudal spine,ECS)对小鼠可移植性肿瘤生长的影响,现将结果报告如下。     

赤魟尾刺提取物的抗肿瘤作用

赤缸Dasyatis akajei（Muller＆henle）隶属于软骨鱼纲，下孔总目，鲼形目，魟科，魟属，常栖息于底质为泥沙的深潭中。赤魟肉性昧甘、咸平，有补气之功效。用其熬油，主治小儿疳积。尾刺研末入药，对治疗胃癌、食道癌、肺癌、乳腺炎、咽喉炎、疟疾、牙痛、魟鱼尾刺刺伤均有一定疗效。赤魟尾刺含有多种毒素，有重要药理作用。涂洪斌等克隆出编码赤魟肿瘤抑制因子IPL的全长cDNA序列，并报道了赤魟亲环素A的融合表达、纯化及活性特征。     

A preliminary approach to the regionalization of the marine comprehensive economic region in Liaoning Province

China is a country with a vast marine territory whose area covers one third of the total land territory area. With the exploitation of marine resources and the development of marine economy, marine economic regions have been formed gradually. We shouldn’t ignore them when we divide economic regions throughout the whole nation, especially in our country. In this paper, we’ Il expand division principles, practice and methods of marine comprehensive economic region. Liaoning Province, facing the Yellow Sea and the Bohai sea, is not only a part of Round-the-Bohai Sea Economic Region, but a part of national marine econemic region. Through evaluating marine resources of Liaoning, and analyzing development of marine economy, composition of marine industries and distributional characteristic of marine economy, Liaoning marine region is divided into Bohai Sea marine economic region and Yellow Sea marine economic region based on differences of marine economy. Thereby we go further into the formation of regional marine economic region and distributional mechanism of regional marine economy. Foundation item: Subsidized by the National Natural Science Foundation of China(49671022). Biography: ZHANG Yao-guang(1934–), male, a native of Shanghai City, professor. His research interest includes marine economic geography.     

Tests to evaluate the ecological impact of treated ballast water on three Chinese marine species

Ballast water has been a topic of concern for some time because of its potential to introduce invasive species to new habitats. To comply with the International Convention for the Control and Management of Ships＇ Ballast Water and Sediments, members of the International Maritime Organization （IMO） must equip their ships with on-board treatment systems to eliminate organism release with ballast water. There are many challenges associated with the implementation of this IMO guideline, one of which is the selection of species for testing the ecological impacts of the treated ballast water. In the United States, ballast water toxicity test methods have been defined by the United States Environmental Protection Agency. However, the test methods had not been finalized in China until the toxicity test methods for ballast water were established in 2008. The Chinese methods have been based on species from three trophic levels： Skeletonema costatum, Neomysis awatschensis, and Ctenogobius gymnauchen. All three species live in broad estuarine and open sea areas of China; they are sensitive to reference toxicants and acclimatize easily to different conditions. In this paper, the biological characteristics, test processes and statistical analysis methods are presented for the three species. Results indicate that the methods for evaluating these three organisms can be included in the ecological toxicity tests for treated ballast water in China.     

Isolation and pharmacological activities of bromophenols from Rhodomela confervoides

Four bromophenols were isolated from the extract of marine red alga, Rhodomela confervoides by column chromatography and HPLC methods. By means of spectroscopic methods including IR, MS, 1D, and 2D-NMR techniques, their structures were elucidated as (1) 3-bromo-4,5-dihydroxy benzoic acid methyl ester; (2) his (2,3-dibromo-4,5-dihydroxybenzyl) ether; (3) 3,4-dibromo-5-(methoxymethyl)-1,2-benzenediol and (4)3-bromo-4,5-dihydroxy-benzaldehyde. Compound 1 was first isolated from the algae in nature, and 1, 4 were found to have selective cytotoxic activities against KB, Bel 7402 and A549 cells, 2 showed powerful antibacterial activities against Staphylococcus aurens and Pseudomonas aeruginosa.     

Influence of dietary n-3 LC-PUFA on growth,nutritional composition and immune function in marine fish Sebastiscus marmoratus

A 60-day feeding experiment was conducted to investigate the influence of dietary omega-3 long-chain polyunsaturated fatty acids(n-3 LC-PUFA) on growth, nutritional composition and immune function of marine fish Sebastiscus marmoratus. Five diets containing 3.6, 10.2, 18.2, 26.5, or 37.0 g/kg n-3 LC-PUFA were prepared. The results reveal significant influences of dietary n-3 LC-PUFA on the final weight, weight gain, specific growth rate, feed conversion ratio, and condition factor. As dietary n-3 LCPUFA increased, weight gain and specific growth rate increased and were significantly higher in groups fed 18.2, 26.5 and 37.0 g/kg than in groups fed 3.6 and 10.2 g/kg( P 0.05); there was no significant difference between groups fed 18.2, 26.5, or 37.0 g/kg( P 0.05). With increasing dietary n-3 LC-PUFA, eicosapentaenoic acid and docosahexenoic acid content in muscle and liver increased significantly, immunoglobulin class M content gradually increased from 9.1 to 14.8 μg/L, and lysozyme activity content increased from 1355 to 2268 U/mL. Broken line model analysis according to weight gain indicated that a dietary n-3 LC-PUFA level of 18.2 g/kg is essential for normal growth at a fat level of 125 g/kg. Therefore, appropriate dietary n-3 LC-PUFA not only promote growth and improve the n-3 LC-PUFA content, but also enhance immune function in S. marmoratus.     

Purification and characterization of 2-haloacid dehalogenase from marine bacterium Paracoccus sp. DEH99, isolated from marine sponge Hymeniacidon perlevis

2-haloacid dehalogenases constitute a group of dehalogenases which are capable of dehalogenating the halogenated organic compounds. So far, the 2-haloacid dehalogenases have been found in many bacteria, but not in Paracoccus genus. In the present study, one enzyme 2-haloacid dehalogenase(designated as Deh99), induced by DL-2-chloropropionate(DL-2-CPA), was purified from the marine bacterium Paracoccus sp. DEH99, isolated from marine sponge Hymeniacidon perlevis. The enzyme of Deh99 was purified to homogeneity by ammonium sulfate precipitation, ion exchange chromatography(Q-Sepharose HP), and Superdex 200 gel filtration chromatography. The molecular weight of Deh99 was estimated to be 25.0 kDa by sodium dodecyl sulfate-polyacrylamide gel electrophoresis(SDS-PAGE), and 50.0 kDa natively by gel filtration chromatography. The enzyme of Deh99 stereospecifically dehalogenated L-2-CPA to produce D-lactate, with an apparent Michaelis-Menten constant(Km) value of 0.21 mmol L-1 for L-2-CPA. The optimal pH and temperature for Deh99 activity were 10.0 and 40℃, respectively. The enzyme of Deh99 acted on short-carbon-chain 2-haloacids, with the highest activity towards monochloroacetate. The activity of Deh99 was slightly affected by DTT and EDTA, but strongly inhibited by Cu2+ and Zn2+. The enzyme of Deh99 shows unique substrate specificity and inhibitor sensitivities compared to previously characterized 2-haloacid dehalogenases and is the reported one about purified 2-haloacid dehalogenase isolated from the bacteria of Paracoccus genus.     

Study on elemental fingerprint of traditional marine Chinese medicine oysters from Jiaozhou Bay, China

In order to investigate the relationship between the trace elements and the characteristics of the oysters, we analyzed the trace elements present in the germplasm of oysters from different producing areas in the Jiaozhou Bay. The element fingerprints were established to reflect the elemental characteristics of the oysters. Concentration patterns of the elements were deciphered by principle component analysis (PCA) and hierarchical cluster analysis (HCA). The six regions were discriminated with accuracy using HCA and PCA based on the concentration of 16 trace elements. The elements were viewed as characteristic elements of the oysters and the fingerprints of these elements could be used to distinguish the quality of the oysters.     

“BOTTLENECK” AND COUNTERMEASURE OF HIGHTECHNOLOGIZATION OF MARINE INDUSTRY IN CHINA

This article deeply researched into the existent five problems and four main “bottlenecks” in the high-technologization of marine industry in China on the basis of analyzing the new trends in international marine problems and the necessity of implementing the strategy of developing China based on marine. This article brought up specific measures to the five “bottlenecks”according to the situations, and pointed out that new marine industry should be high-technologization and the traditional marine industry should be reformed by high-technique. The research results mav nrovide the scientific basis for realizing the high-technologization of marine industry in China.     

Diversity and bioactivity of actinomycetes from marine sediments of the Yellow Sea

Among the 116 actinomycetes collected from marine sediments of the Yellow Sea,56 grew slowly and appeared after 2?3 weeks of incubation.Among the 56 strains,only 3 required seawater(SW) for growth,and 21 grew well in the medium prepared with SW rather than distilled water(DW),while the remaining 32 grew well either with SW or with DW.Six representatives with different morphological characteristics,including 1 SW-requiring strain and 5 well-growing with SW strains,were selected for phy-logenetic analysis based on 16S rRNA gene.Two strains belong to Micrococcaceae and Nocardiopsaceae respectively.The other 4 strains belong to the family of Streptomycetaceae.In the analyzed 6 strains,one was related to Nocardiopsis spp.and the other three were related to Streptomyces spp.,representing new taxa.Bioactivity testing of fermentation products from 3 SW-requiring strains and 21 well-growing with SW strains revealed that 17 strains possessed remarkable activities against gram-positive pathogen or/and tumor cells,suggesting that they were prolific resources for natural drug discovery.     

ARTIFICIAL PROPAGATION AND BREEDING OF MARINE FISH IN CHINA

Since the 1990s, artificial propagation and breeding technique of marine fish in China have developed by way of increasing species and fry numbers, with special stress laid on valuable species. Large quantities of artificial fry can meet the needs of both marine cage culture and pond culture for most species. Experimental results obtained by scientists have been put into use in actual production.Fish fry production has entered a period of sustainable development. So far, at least 44 species (21 families) of marine fish have been successfully bred in China. The artificial fry number of large yellow croaker ( Pseudosciaena crocea) exceeded 300 million in 1999. The species whose artificial fry numbers have each surpassed 10 million annually are red drum ( Sciaenops ocellatus ), Japanese seabass ( Lateolabrax japonicus), cuneate drum (Nibea miichthioides ), spring spawning red seabream (Pagrosomus major ) and threebanded sweethp ( Plectorhynchus cinctus ). Millions of artificial fry are bred annually in the species of black porgy ( Sparus macrocephalus ), Russell‘ s snapper ( Lutjanus russeUi ), javelin gnmt ( Pomadasys hasta ), miiuy croaker ( Miichthys miiuy) and skewband gnmt ( Hapalogenys nitens ). The fish in the family Sciaenidae are the main species in artificial propagation and breeding. Some problems and prospects on marine fish culture and stock enhancement are also discussed and some proposals for sustainable development are put forward in this article.     

STUDY ON THE CORROSION PEAK OF CARBON STEEL IN MARINE SPLASH ZONE

lNTRODUCTI0NSincetheoonceptofrnarinesplashzone(MSZ)wasfirstproposedbyHumble,rnanyresearchesprovedthatthecorrosionofsteelinthesplashzoneisthemostseriousinthemarineenvironninetandthatthisMSZcorrosionhasapeak(Zhu,l995).Howevertheenvironmentalfactorscatisingthecorrosionpeakwasnotkn0wnthen(Niat0,l975,Atsushi,l994)andtherangeoftheMSZwasnotyetdeariydefinedopzkaki,l985).ThispaperexplainsthemaincauseofthecormsionpeakanddefinestheexaCtrangeoftheMSZinsomeofChina'sharbours.MATERIALSANDMET…     

Inhibition of Aspergillus parasiticus and cancer cells by marine actinomycete strains

Ten actinomycete strains isolated from the Yellow Sea off China's coasts were identified as belonging to two genera by 16 S r DNA phylogenetic analysis: Streptomyces and Nocardiopsis. Six Streptomyces strains(MA10, 2SHXF01-3, MA35, MA05-2, MA05-2-1 and MA08-1) and one Nocardiopsis strain(MA03) were predicted to have the potential to produce aromatic polyketides based on the analysis of the KSα(ketoacyl-synthase) gene in the type II PKS(polyketides synthase) gene cluster. Four strains(MA03, MA01, MA10 and MA05-2) exhibited significant inhibitory effects on mycelia growth(inhibition rate 50%) and subsequent aflatoxin production(inhibition rate 75%) of the mutant aflatoxigenic Aspergillus parasiticus NFRI-95. The ethyl acetate extracts of the broth of these four strains displayed significant inhibitory effects on mycelia growth, and the IC50 values were calculated(MA03: 0.275 mg m L-1, MA01: 0.106 mg m L-1, MA10: 1.345 mg m L-1 and MA05-2: 1.362 mg m L-1). Five strains(2SHXF01-3, MA03, MA05-2, MA01 and MA08-1) were selected based on their high cytotoxic activities. The ethyl acetate extract of the Nocardiopsis strain MA03 was particularly noted for its high antitumor activity against human carcinomas of the cervix(He La), lung(A549), kidney(Caki-1) and liver(Hep G2)(IC50: 2.890, 1.981, 3.032 and 2.603 μg m L-1, respectively). The extract also remarkably inhibited colony formation of He La cells at an extremely low concentration(0.5 μg m L-1). This study highlights that marine-derived actinomycetes are a huge resource of compounds for the biological control of aflatoxin contamination and the development of novel drugs for human carcinomas.     

Total lipid and fatty acid composition of eight strains of marine diatoms

Fatty acid composition and total lipid content of 8 strains of marine diatoms (Nitzschia frustrula, Nitzschia closterium, Nitzschia incerta, Navicula pelliculosa, Phaeodactylum tricornutum, Synedra fragilaroides) were examined. The microalgae were grown under defined conditions and harvested at the late exponential phase. The major fatty acids in most strains were 14∶0 (1.0%–6.3%), 16∶0 (13.5–26.4%), 16∶1n−7 (21.1%–46.3%) and 20∶5n−3 (6.5%–19.5%). The polyunsaturated fatty acids 16∶2n−4, 16∶3n−4, 16∶4n−1 and 20∶4n−6 also comprised a significant proportion of the total fatty acids in some strains. The characteristic fatty acid composition of diatoms is readily distinguishable from those of other microalgal groups. Significant concentration of the polyunsaturated fatty acid 20∶5n−3 (eicosapentaenoic acid) was present in each strain, with the highest proportion in B222 (19.5%). Project supported by the Hi-Tech “863” Programs of the China Ministry of Science and Technology (863-819-02-01).     

Adjoint Assimilation in Marine and an Example of Application

This paper aims at a review of the work carried out to date on the adjoint assimilation of data in marine ecosystem models since 1995. The structure and feature of the adjoint assimilation in marine ecosystem models are also introduced. To illustrate the application of the adjoint technique and its merits, a 4-variable ecosystem model coupled with a 3-D physical model is established for the Bohai Sea and the Yellow Sea. The chlorophyll concentration data derived from the SeaWiFS ocean colour data are assimilated in the model with the technique. Some results are briefly presented.