Antibacterial activity of extracts from <Emphasis Type="Italic">Zostera marina</Emphasis> against pathogens of <Emphasis Type="Italic">Apostichopus japonicus</Emphasis> skin ulceration disease

The purpose of this study was to investigate the antibacterial activity of extracts from Zostera marina against the pathogens of Apostichopus japonicus skin ulceration disease. When 95% ethanol (v/v) solvent was used to extract Zostera marina at 50°C, aqueous extract (ZA) showed obvious bacteriostatic effects on the tested bacterial strains (inhibition halo diameters between 8.23 mm and 13.62 mm), whereas the ethyl acetate extract (ZE) was almost inactive. The minimal inhibitory concentration (MIC) of ZA against four pathogens were homogeneous at 12.8 g L⁻¹. ZA components were analyzed by thin layer chromatography (TLC) assay and six fractions were obtained. In another study, the six fractions showed inhibitory effects against the tested bacteria while their functions seemed to counteract the ZA activity.     

Antibacterial Activity of Extracts from Zostera marina Against Pathogens of Apostichopus japonicus Skin Ulceration Disease

The purpose of this study was to investigate the antibacterial activity of extracts from Zostera marina against the pathogens of Apostichopus japonicus skin ulceration disease.When 95% ethanol (v/v) solvent was used to extract Zostera marina at 50℃,aqueous extract (ZA) showed obvious bacteriostatic effects on the tested bacterial strains (inhibition halo diameters between 8.23 mm and 13.62 mm),whereas the ethyl acetate extract (ZE) was almost inactive.The minimal inhibitory concentration (MIC) of ZA against four pathogens were homogeneous at 12.8 g L-1.ZA components were analyzed by thin layer chromatography (TLC) assay and six fractions were obtained.In another study,the six fractions showed inhibitory effects against the tested bacteria while their functions seemed to counteract the ZA activity.     

Influence of temperature and salinity on germination of eelgrass (Zostera marina L.) seeds

Seagrass restoration as part of ocean ecosystem protection has been launched for many years all over the world, but intensive research on this subject in China has just begun in recent years. Seed broadcasting has been widely accepted as the most potentially useful method for seagrass restoration over large areas. We examined the influence of key environmental factors on seed germination to help promote eelgrass bed restoration. Under anoxic conditions, the influence of temperature and salinity on the germination rate of eelgrass (Zostera marina L.) seeds was examined at different combinations of four temperatures (4, 9, 14, and 24°C) and nine salinities (5 to 45, increment of 5). The effect of significant interaction of temperature and salinity on germination rate was observed (ANOVA) (P<0.001). The highest germination rate (83.3 ± 3.5)% was reached in 8 weeks at 14°C and salinity 5. Higher temperature significantly increased the germination rate at salinity 5 (P<0.001) during the whole observation period except for 24°C, while lower salinity significantly increased the germination rate at 14°C (P<0.001). Although significant interaction was found between temperature and salinity (P<0.001), the influence of salinity was stronger than that of temperature for the germination of eelgrass seeds. These results provide useful information for the propagation of artificial seedlings for seagrass restoration in China.     

Biotic and Abiotic Conditions Can Change the Reproductive Allocation of Zostera marina Inhabiting the Coastal Areas of North China

The relationships between reproductive allocation and different factors have been widely recognized for terrestrial plants, but scarcely for marine angiosperms. Focusing on the seagrass Zostera marina, we examined the change in biomass when it was partitioned to growth, vegetative propagation and reproductive allocation of Z. marina. We also evaluated the relationships between reproductive allocation and biotic and abiotic conditions in the coastal areas of north China. The results indicated that the reproductive allocation of Z. marina at the levels of genet, shoot and spathe was positively correlated with shoot characteristics such as height and biomass(P < 0.01), but was negatively correlated with branch number and leaf number per genet(P < 0.01). In addition, the allocation was also affected by other abiotic factors such as water column phosphate concentration(P < 0.05) and sediment total petroleum(P < 0.01). These findings indicated that both biotic and abiotic conditions significantly influenced the reproductive allocation of Z. marina, which may affect further the population dynamics.     

16S rRNA Gene Phylogenesis of Culturable Predominant Bacteria from Diseased Apostichopus japonicus(Holothuroidea,Echinodermata)

Cultured Apostichopusjaponicus in China suffers from a kind of skin ulceration disease that has caused severe economic loss in recent years. The disease, pathogens of which are supposed to be bacteria by most researchers, is highly infectious and can often cause all individuals in the same culture pool to die in a very short time. The 16S rRNA gene phylogenesis of the culturable bacteria from the lesions of diseased individuals was conducted to study the biodiversity of the bacterial communities in the lesions and to identify probable pathogen(s) associated with this kind of disease. S. japonica samples were selected from a hatchery located in the eastern part of Qingdao, China. Bacterial universal primers GM5F and DS907R were used to amplify the 16S rRNA gene of bacteria colonies, and touchdown PCR was performed to amplify the target sequences. The results suggest that γ- proteobacteria (Alteromonadales and Vibrionales) of CFB group, many strains of which have been also determined as pathogens in other marine species, are the predominant bacterial genera of the diseased Apostichopusjaponicus individuals.     

低值鱼蛋白多肽-铁（Ⅱ）螯合物的酶解制备及其抗氧化、抗菌活性

以南海低值鱼蛋白为原料，采用木瓜蛋白酶和风味酶的复合酶水解得到多肽水解物（HP），并制备多肽．铁（Ⅱ）螯合物，对螯合工艺及螯合产物的结果及抗氧化和抗菌功能特性进行了初步研究。结果表明：1）水解度为5％的多肽与铁（Ⅱ）螯合效果最佳，螯合率为94．15％；2）化学分析及红外光谱表明活性肽与亚铁离子螯合并形成稳定结构的螯合物；（3）经过50％乙醇（体积分数）沉淀的螯合铁具有明显的抗氧化活性，其抗氧化作用相当于维生素E的90％，经过80％乙醇（体积分数）沉淀的螯合物具有显著的抗枯草牙孢杆菌和金黄色葡萄球菌活性，其抑菌圈均直径为13mm。     

低值鱼蛋白多肽-铁(Ⅱ)螯合物的酶解制备及其抗氧化、抗菌活性

以南海低值鱼蛋白为原料,采用木瓜蛋白酶和风味酶的复合酶水解得到多肽水解物(HP),并制备多肽-铁(Ⅱ)螯合物,对螯合工艺及螯合产物的结果及抗氧化和抗菌功能特性进行了初步研究。结果表明:1)水解度为5%的多肽与铁(Ⅱ)螯合效果最佳,螯合率为94.15%;2)化学分析及红外光谱表明活性肽与亚铁离子螯合并形成稳定结构的螯合物;(3)经过50%乙醇(体积分数)沉淀的螯合铁具有明显的抗氧化活性,其抗氧化作用相当于维生素E的90%,经过80%乙醇(体积分数)沉淀的螯合物具有显著的抗枯草牙孢杆菌和金黄色葡萄球菌活性,其抑菌圈均直径为13mm。     

16S rRNA gene phylogenesis of culturable predominant bacteria from diseased Apostichopus japonicus (Holothuroidea, Echinodermata)

Cultured Apostichopus japonicus in China suffers from a kind of skin ulceration disease that has caused severe economic loss in recent years. The disease, pathogens of which are supposed to be bacteria by most researchers, is highly infectious and can often cause all individuals in the same culture pool to die in a very short time. The 16S rRNA gene phylogenesis of the culturable bacteria from the lesions of diseased individuals was conducted to study the biodiversity of the bacterial communities in the lesions and to identify probable pathogen(s) associated with this kind of disease. S. japonica samples were selected from a hatchery located in the eastern part of Qingdao, China. Bacterial universal primers GM5F and DS907R were used to amplify the 16S rRNA gene of bacteria colonies, and touchdown PCR was performed to amplify the target sequences. The results suggest that γ- proteobacteria (Alteromonadales and Vibrionales) of CFB group, many strains of which have been also determined as pathogens in other marine species, are the predominant bacterial genera of the diseased Apostichopus japonicus individuals.     

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。     

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。     

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.