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1.
We determined the effects of 16 wk of storage at low temperature (4 C) in darkness on the viability, growth, photosynthetic parameters, and biochemical composition of four diatom cultures. Significant differences in cell density and proximal composition were observed for all diatoms throughout storage. Cell density increased with time of storage for all diatoms. Protein content increased for Navicula incerta, Nitzschia laevis, and Navicula sp., whereas lipid content increased during storage in only N. incerta. When the stored diatoms were used as inocula in fresh medium, they increased their viability, generating a lag phase for Nitzschia thermalis var. minor, N. incerta, and Navicula sp. cultures. There were noted species‐specific modifications in proximal composition, ash‐free dry weight, and photosynthetic parameters in response to storage. We conclude that N. thermalis, N. incerta, N. laevis, and Navicula sp. can be stored at 4 C for 16 wk and are viable in new cultures.  相似文献   

2.
We measured the proximal composition of four benthic diatoms that were stored for 24 mo in the dark at low temperature (4 C by refrigeration) and examined their potential as feed for abalone, Haliotis rufescens, postlarvae. The proximal composition of the four diatoms was modified by species‐specific responses as a function of time in storage. The cultures of all stored diatoms contained low or undetectable concentrations of Vibrio‐like bacteria (<0.01 VLB/mL). As feed for abalone postlarvae, the four diatoms promoted growth under all experimental conditions. Greater shell lengths were measured on Day 14 when Navicula sp. and Navicula incerta were used as feed. Postlarvae that were fed N. incerta and Navicula sp. had higher growth rates. In contrast, lower growth rates were observed on Day 7 with fresh and stored Nitzschia thermalis as food. Survival was high in postlarvae that were fed the four stored diatoms (100%). This report demonstrates that cultures of benthic diatoms that have been stored by refrigeration for 24 mo can be used to feed abalone postlarvae and have an effect on improving growth and survival.  相似文献   

3.
通过周年取样、分析测定和生物量统计等方法对大连地区仿刺参养殖池塘底栖硅藻生产状况的周年变化进行了研究。结果发现,试验池塘底栖硅藻初级生产力均值为(3.52±0.21)g/(m2.d),其值变化为1.12~7.63g/(m2.d),最大值出现在8月初,最小值出现在3—4月;底栖硅藻初级生产力与pH呈显著正相关,并受透明度及pH与透明度交互作用影响;底泥叶绿素a与透明度呈极显著负相关。  相似文献   

4.
ABSTRACT

We investigated the quality characteristics of cookies prepared using different seaweeds native to the Korean coast. Flour made from four different seaweed species (Sargassum fulvellum, Enteromorpha linza, Codium fragile, and Hizikia fusiforme) was used to replace 5% of the regular flour while preparing the cookies. The seaweeds significantly affected solvent retention capacity, thus interfering with gluten network formation. Consequently, the addition of seaweed changed several variables in the cookies, such as moisture content, spread factor, and breaking stress. In sensory evaluation, cookies with Hizikia fusiforme were the most preferred, confirming the possibility of developing cookie products using this seaweed species.  相似文献   

5.
产胞外多糖的近海海洋细菌的筛选   总被引:3,自引:0,他引:3  
海洋微生物是海洋生物的重要组成部分,海洋微生物可产生大量不同于陆生生物的活性物质,是重要的海洋药物资源。实验所用泥样采集于黄海近海海岸,对其进行海洋细菌的分离与纯化,获得了25株纯化的海洋细菌。采用苯酚-硫酸法和乙醇沉淀法检测这些菌株的发酵液中是否含有胞外多糖,进一步筛选出胞外多糖的高产菌株。实验结果表明,胞外多糖产量高于0.22g/L的菌株共7株,占总测定菌株数的28%,胞外多糖产量高于0.20g/L的菌株共13株,占总测定菌株数的52%。有48%的菌株胞外多糖产量介于0.19g/L和0.20g/L之间。其中以MBN003中多糖含量为最高,产量达到0.2305g/L。此研究结果表明MBN003菌株具有较高的产胞外多糖能力,可以选用MBN003作为胞外多糖提取物研究的来源。  相似文献   

6.
如东的沿海、滩涂资源丰富,作者详细论述了如东的沿海、滩涂及海洋经济的可持续发展的现状、发展前景。  相似文献   

7.
为验证由生产培养获得的不同质量的底栖硅藻培养皱纹盘鲍不同生长阶段幼体的效果,采用经不同培养措施获得的两类底栖硅藻群落(饵料A和饵料B)培养皱纹盘鲍前期匍訇幼体和稚鲍.试验结果表明,饵料A培养前期匍匐幼体的存活率[(43.47±13.53)%]显著高于饵料B[(6.94±5.17)%],但生长指标差异不显著.两类饵料培养的稚鲍存活率差异不显著,但饵料B的生长速度和特定生长率[(0.151±0.025)mm/d和(4.706±0.492)%/d)]显著高于饵料A[(0.103±0.022)mm/d和(3.625±0.374)%/d)].说明皱纹盘鲍幼体在不同生长阶段适应底栖硅藻的种类不同.匍匐幼体期对底栖硅藻质量要求较高,稚鲍期由于食量增加和食性转化,对饵料数量的要求表现得更为明显.  相似文献   

8.
本文通过调查8个沿海工厂直排口、1个混合排污口、6条入海河流、4个市政下水口、海洋船舶、港口、海水养殖向海域排污状况以及农业使用污染物质情况等,初步掌握了茂名市海洋污染源情况。调查结果显示,茂名市海洋环境状况是良好的,全市排入海域的总水量23,481.644万t,污染物质总量为3,816.84t,各种排海主要污染物排放量按大小依次为化学需氧量、石油类、悬浮物、氨氮、生化需氧量、硫化物、磷等,其排放量分别为2,796.235t、438.092t、436.8t、75.1t、32.9t、25.965t和5.6t。茂名市海洋污染源排海主要污染物是石油类、化学需氧量、硫化物、磷,累计等标排污量占82.45%。  相似文献   

9.
The biochemical composition of six seahorse species from the Chinese coast was analyzed in this study. The crude protein content (% dry weight) of Hippocampus kuda, Hippocampus trimaculatus, Hippocampus kelloggi, Hippocampus spinosissimus, Hippocampus histrix, and Hippocampus comes was 70.70 ± 2.12%, 77.59 ± 1.06%, 78.31 ± 1.74%, 71.15 ± 1.32%, 68.07 ± 1.96%, and 76.59 ± 3.25%, respectively. The major amino acids (>5% of the total) in seahorses were arginine, aspartic acid, glutamic acid, alanine, and glycine, and there were significant differences in essential amino acids (EAA) (as % of total protein) among the six species (P < 0.05). The scores of EAA were balanced in the seahorse species, and the essential amino acid indexes of the six species were 41.63, 40.89, 44.84, 39.60, 39.31 and 45.45, respectively. The content of flavor‐enhancing amino acids of the six seahorse species was generally high, ranging from 28.16 ± 1.12% in H. histrix to 32.90 ± 2.17% in H. kelloggi (P < 0.05). The total lipid content was generally low, ranging from 0.96 ± 0.08% in H. histrix to 2.02 ± 0.24% in H. comes. The most abundant fatty acid was C16:0, ranging from 15.04 ± 0.67% in H. trimaculatus to 31.04 ± 4.32% in H. spinosissimus. The combination of eicosapentaenoic acid and docosahexaenoic acid as the fraction of the total fatty acids was high (0.14–0.35). The polyunsaturated fatty acid/saturated fatty acid ratio ranged from 0.40 in H. kuda to 1.19 in H. histrix. The trace metal concentrations in the seahorses were generally low. The six seahorse species examined provide a food source for humans with low fat, high protein, good levels of EAA, and high beneficial trace elements. These results are valuable in developing diets for culturing seahorse species.  相似文献   

10.
地方种类是我国海水鱼养殖的主要品种来源。本文列举了我国目前养殖的主要海水鱼种类及其苗种来源,阐述了驯养野生的地方种类的优势所在及其在养殖开发中存在的问题与对策。  相似文献   

11.
徐承良 《水产学杂志》2005,18(2):97-100
通过示图和文字说明,对冷藏集装箱的结构、设备布置、制冷工艺、技术参数和控制方式进行了系统的介绍,详细地说明了制冷技术通过先进的控制技术在集装箱中的应用。  相似文献   

12.
Pacific white shrimp (Litopenaeus vannamei) is an important species in aquaculture worldwide. Post-mortem changes during cold storage reduce the quality of shrimp and shorten its shelf life. Cold plasma (CP) was applied for 45, 90, and 150s as T1, T2, and T3, respectively, to fresh harvested shrimp. The biochemical parameters and melanosis were analyzed in comparison to metabisulphite treated (TM) and control during 12 days of refrigerated storage. The results highlighted lower rate of increase in pH, total volatile base nitrogen (TVB-N) content, thiobarbituric acid reactive substances (TBARS), free fatty acid (FFA), peroxide value (PV), and fluorescent compounds (FC) in shrimp exposed to CP and metabisulphite compared to control (P < 0.05). Although CP lowered biochemical changes in T1 and T3 shrimp, T2 was the most effective treatment in reducing undesirable changes and improving quality of shrimp. In all storage periods, melanosis was significantly lower in T2, T3, and TM samples. Results demonstrate that CP exposure effectively decreases relative activity of polyphenol oxidase (PPO) enzyme, and prolonging the exposure to CP for 150 s resulted in 50% reduction in enzyme activity. We conclude that application of CP for 90 s was the most efficient circumstance to extend shelf life of white shrimp during cold storage.  相似文献   

13.
Impact of climate change on marine biogeochemical parameters and ecosystem is one of the important issues of our environment. Direct evidence of marine pelagic ecosystem changes is found with warming of sea water and sea‐level rise in the main stream of the Kuroshio in the East China Sea and the western North Pacific during these three decades based on the analysis of long‐term comprehensive hydrographic observations. In terms of annual mean, the warming rate of surface air temperature and sea surface temperature ranged from 0.15 to 0.21°C per decade in and around the main stream of the Kuroshio in the East China Sea, which exceed the global mean warming rate of 0.128 ± 0.026°C per decade during the period from 1956 to 2005 reported in IPCC 2007. One of the features in this rapid warming region is an increase of number of Pterosagitta draco, a cosmopolitan warm‐water zooplankton. Biogeochemical parameters, such as wet weight of zooplankton, plant pigment and nutrients concentration in the upper 200 m have been decreasing while dissolved oxygen content and seawater temperature have been increasing in the upper 200 m in the main stream of the Kuroshio in the East China Sea. These observed linear trends of the biogeochemical parameters would be foresights for temperate oceans in the future.  相似文献   

14.
氟苯尼考对六种海洋致病弧菌的体外抗菌活性研究   总被引:17,自引:0,他引:17  
测定了氟苯尼考等4种抗菌药对6种常见海洋致病弧菌的最小抑菌浓度(MIC)和最小杀菌浓度(MBC)。测试结果显示,氟苯尼考对6株弧菌的MIC值范围为2~4μg/mL,氯霉素为1~32μg/mL,土霉素为4~128μg/mL,恩诺沙星为0.125~1μg/mL;对多数弧菌氟苯尼考与氯霉素的抗菌活性相似。氟苯尼考对6株弧菌的MBC/MIC值范围为2-4,而氯霉素为2~16,表明氟苯尼考的杀菌效果优于氯霉素。对照药物恩诺沙星、土霉素的MBC/MIC值分别为1-2和2-8,恩诺沙星显示出优良的抗菌和杀菌活性。随着接种菌量增加,所测3种抗菌药的MIC随之升高;当接种量达到10^7ufu/mL时.药物对多数弧菌显示出微弱的作用。  相似文献   

15.
依据1995~1997年对大窑湾浮筏养殖区水环境主要因子及养殖状况调查,论述二者之间相互关系,初步探明该海区具有贫磷富氮的特性;3年中该湾富营养化程度逐年减弱。初级生产力水平1997年〈1996年〈1995年,面3年中养殖状况为:太平洋牡蛎死亡率1995年〉1996年〉1997年,牡蛎出内率1995年〉1996年〉1997年。  相似文献   

16.
ABSTRACT

This study characterized the functional properties of ethyl acetate-methanol (EA-MeOH) and chloroform extracts of the muricid gastropod Chicoreus ramosus and buccinid Babylonia spirata. The EA-MeOH extract of B. spirata was a potent quencher of radical cation (IC90 < 1 mg/mL), whereas that of C. ramosus held greater anti–inflammatory potential (IC90 5-lipoxygenase inhibition 1.74 mg/mL) than the buccinid gastropod. The EA-MeOH extract of C. ramosus displayed potent antidiabetic activities as deduced by its attenuation properties against carbolytic enzymes α-amylase and α-glycosidase (IC90 1.06 and 2.25 mg/mL, respectively) than those exhibited by B. spirata (IC90 2.32 and 4.50 mg/mL, respectively). The spectroscopic dereplication studies to determine probable chemical groups in the solvent extracts of the studied gastropods revealed the presence of functionalities, which might augment the electronic properties of the bioactive principles present within the extract, thereby enhancing their activity. Thus, the present study recognized that marine gastropods C. ramosus and B. spirata have potential functional implications against oxidative stress-induced diseases, such as diabetes and inflammation. This research supports further investigation of these previously uncharacterized marine gastropod species to isolate potential bioactive leads for use against various biological targets and to develop functional food formulations.  相似文献   

17.
陈爱华 《齐鲁渔业》2007,24(7):40-42
探讨了重金属对水生生物的危害及底栖动物对重金属的生物可利用性,指出海洋底栖动物对重金属治理有着巨大作用。  相似文献   

18.
19.
The Pacific Calico scallop, Argopecten ventricosus (Sowerby), is the most important commercial species in Bahia Concepcion. Catches declined steadily from 1991 to 1993 as a result of overexploitation, forcing the adoption of management measures. The Government has now established regulations for exploitation and scallop culture development. In 1994, Centro Interdisciplinario de Ciencias Marinas (CICIMAR) and the Fisheries Department of the Mexican Government initiated research on the feasibility of increasing scallop biomass through a reseeding programme to protect artisanal fishing. The use of onion bags to collect spat in Bahia Concepcion (1988-1994) demonstrated that settlement was cumulative from January to March. At Punta Coloradito, there were two peaks, in January and early March. Commercial collectors were deployed in February at El Indio and in April at El Remate. In June, about one million juvenile scallops were placed in an enclosure, held until mid-August and then released. Mass mortality (>80%) of the scallops was observed in September, increasing to 99% in October. The high water temperature and predators may be responsible for the mortalities.  相似文献   

20.
ABSTRACT:   Growth and ontogenetic migration of greeneye Chlorophthalmus albatrossis were studied in the area from 100–400 m depths in Tosa Bay, from April 1996 to March 1997, using samples collected by an otter trawl net with a 1.3 mm mesh cod end. In the monthly changes of the standard length (SL) composition, four year classes were recognized, although the third- and fourth-year classes were not clearly separated in all the monthly samples. Individuals of 40–50 mm SL settled on the bottom of the 150–200 m depth zone from August to February. By May and June, they grew to 75–80 mm SL modal size, and migrated to 200–300 m depth. In one year after settlement, they grew to 125–130 mm SL, and migrated to 300–350 m depth. They grew to a maximum of 160 mm SL and were not sampled in the winter three years after settlement, suggesting either migration or mortality. Seasonal changes in the gonadosomatic index for combined samples of males and females showed that greeneye did not mature in Tosa Bay. It is suggested that the planktonic larvae are transported from the spawning grounds, the location of which remains unknown.  相似文献   

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