Mesohabitat associations of the threatened San Marcos salamander (Eurycea nana) across its geographic range          下载免费PDF全文

Peter H. Diaz  Joe N. Fries  Timothy H. Bonner  Mara L. Alexander  Weston H. Nowlin 《水产资源保护:海洋与淡水生态系统》2015,25(3):307-321

热稳定脱脂米糠蛋白质碳水化合物酶-蛋白酶分步提取法酶的筛选和条件优化     

廖世鹏  唐善虎  刘鲁蜀  张荣  杨蓉生  龙虎  周相吉  N Hettiarachchy 《畜禽业》2007,(1):4-6

热稳定脱脂米糠(HDRB)中蛋白质已严重变性,采用常规方法很难提取其中蛋白质。本研究其目的在于评价不同碳水化合物酶和蛋白质水解酶组合在HDRB蛋白质提取的作用,以及利用响应曲面方法优化蛋白质提取组合条件。结果发现使用果胶酶P-Ⅱ处理HDRB,继后对其残渣进行蛋白酶P处理,蛋白质提取率可达到80%。采用中心成分回归设计进一步对果胶酶P-Ⅱ、蛋白酶P、水糠比、温度、pH、提取时间进行RSM优化,最大蛋白质提取率可达到89%。本研究为合理利用米糠蛋白及利用米糠蛋白制备功能性短肽提供了可靠的方法。  相似文献   

Effects of Partial and Complete Replacement of Synthetic Cryoprotectant with Carrot (Daucus carota) Concentrated Protein on Stability of Frozen Surimi     

Sanjeev Sharma  K. Siddhnath  N. K. Mehta  Apurba Saha  Shubham Gupta 《Journal Of Aquatic Food Product Technology》2013,22(8):808-820

ABSTRACT

The study aimed to evaluate the effects of carrot concentrated protein (CCP) as additive on the functional and textural properties of surimi from striped catfish (Pangasianodon hypophthalmus) during six months of frozen storage (?20°C). The CCP (82.22% crude protein) was used as an additive either a lone or with a synthetic cryoprotectant (sucrose-sorbitol-sodium tri-polyphosphate). Control was made with synthetic cryoprotectant only. Molecular weight of CCP was found to be 36 kDa. After six months, the results revealed that up to 50% of synthetic cryoprotectants could be replaced by CCP during frozen storage of surimi. Biochemical parameters such as protein solubility, Ca²⁺ATPase activity, and gel strength decreased significantly (p < .05) during storage. Treatment T-3 (CCP 0.5% + 50% of synthetic cryoprotectant) maintained quality of protein significantly superior (p < .05) in respect to denaturation and other functional and sensory attributes compared to all the treatments. The microstructure images of surimi confirmed that addition of CCP modified the ice crystal growth during frozen storage. This study suggests that CCP can be a potential additive to protect protein from denaturation along with partial replacement of chemical cryoprotectants.  相似文献   

High yield and rapid growth of Neoparamoeba pemaquidensis in co-culture with a rainbow trout gill-derived cell line RTgill-W1     

Lee LE  Van Es SJ  Walsh SK  Rainnie DJ  Donay N  Summerfield R  Cawthorn RJ 《Journal of fish diseases》2006,29(8):467-480

Neoparamoeba pemaquidensis is an ubiquitous amphizoic marine protozoan and has been implicated as the causative agent for several diseases in marine organisms, most notably amoebic gill disease (AGD) in Atlantic salmon. Despite several reports on the pathology of AGD, relatively little is known about the protozoan and its relationship to host cells. In this study, an in vitro approach using monolayers of a rainbow trout gill cell line (RTgill-W1, ATCC CRL-2523) was used to rapidly grow large numbers of N. pemaquidensis (ATCC 50172) and investigate cell-pathogen interactions. Established cell lines derived from other tissues of rainbow trout and other fish species were also evaluated for amoeba growth support. The amoebae showed preference and highest yield when grown with RTgill-W1 over nine other tested fish cell lines. Amoeba yields could reach as high as 5 x 10(5) cells mL(-1) within 3 days of growth on the gill cell monolayers. The amoebae caused visible focal lesions in RTgill-W1 monolayers within 24 h of exposure and rapidly proliferated and spread with cytopathic effects destroying the neighbouring pavement-like cells within 48-72 h after initial exposure in media above 700 mOsm kg(-1). Disruption of the integrity of the gill cell monolayers could be noted within 30 min of exposure to the amoeba suspensions by changes in transepithelial resistance (TER) compared with control cell monolayers maintained in the exposure media. This was significantly different by 2 h (P < 0.05) compared with control cells and remained significantly different (P < 0.01) for the remaining 72 h that the TER was monitored. The RTgill-W1 cell line is thus a convenient model for growing N. pemaquidensis and for studying host-pathogen interactions in AGD.  相似文献   

The secretion of amylase, phospholipase and protease from Aeromonas salmonicida, and the correlation with membrane-associated ribosomes     

C. M. CAMPBELL  D. DUNCAN  N. C. PRICE  L. STEVENS 《Journal of fish diseases》1990,13(6):463-474

Abstract. The following extracellular enzymes have been readily detected in the culture filtrates from Aeromonas salmonicida: amylase, phospholipase, lysophospholipase and ribonuclease. Amylase and phospholipase have been partially characterized. Evidence suggests that glycogen may be the natural substrate for amylase, and that the role of the enzyme in natural infection is to digest glycogen present in fish muscle. The secretion of amylase activity is suppressed by the addition of glucose to the growth medium. The amounts of amylase, phospholipase and protease that can be detected in culture filtrates decreases with increase in the growth temperature from 25 to 32°C. This marked decrease in secretion of hydrolytic enzymes occurs although the initial growth rates at 25 and 32°C are similar. Free and membrane associated ribosomes have been isolated from cultures grown at 25 and 32°C. At 32°C there is a smaller proportion of membrane-associated ribosomes and this is consistent with the hypothesis that extracellular enzymes from Aeromonas salmonicida are secreted on membrane-bound polysomes.  相似文献   

A comparison of the population genetics of Lethrinus miniatus and Lutjanus sebae from the east and west coasts of Australia: Evidence for panmixia and isolation     

Lynne van Herwerden  William J. Aspden  Stephen J. Newman  Graham G. Pegg  Leica Briskey  William Sinclair   《Fisheries Research》2009,100(2):148-155

Lethrinus miniatus and Lutjanus sebae are important commercial and recreational species of reef fish. Within Australian waters the former species is less widespread than the latter and has a discontinuous distribution, whilst the latter is continuously distributed in tropical Australian waters. The demographic attributes of these species (e.g. long life span, low rates of natural mortality) make them vulnerable to over-exploitation. Consequently, conservative harvest strategies including no-take zones for these species have been adopted by fisheries management agencies to control exploitation. Information on the genetic stock structure of these species is important for developing specific management strategies. However, little is known about genetic stock structures within and between east and west Australian populations of these species. The current study used the mitochondrial genome hypervariable region 1 (HVR1) of the control region to examine variation between two sites from both the east and west Australian coasts for each species. HVR1 for L. sebae did not differ genetically either within or between coasts (F_st < 0.018, p > 0.15) at the sites studied, suggesting a panmictic population structure. Similarly, L. miniatus did not differ significantly between sites sampled within coast. However, the west coast HVR1 for L. miniatus east and west coast populations, were discrete (F_st of at least 0.92, p < 0.0001). The degree of genetic sub-division between east and west coast populations indicates that they should be managed as discrete stocks. Further, when considering both species, the lower genetic (both haplotype and nucleotide) diversity in three of the four sites on the west coast of Australia, indicates that this region is genetically impoverished and neutrality tests suggest that selection is responsible. Consequently, west Australian populations will be less resilient to perturbations (e.g. fishing, climate change) than east Australian populations, which have higher genetic diversity.  相似文献   

牙鲆tyrp1a和tyrp1b的鉴定及tyrp1a与mmu-miR-143-5p_R+2的调控关系          下载免费PDF全文

王若青  王娜  王仁凯  陈松林 《渔业科学进展》2018,39(2):49-58

为了研究牙鲆白化发生过程中的分子调控机制,本研究在获得正常和白化牙鲆转录组及micro RNA(mi RNA)深度测序数据的基础上,对tyrosinase related protein 1(tyrp1)和mmu-mi R-143-5p_R+2(mmu-143)进行了表达模式、靶基因预测及验证分析。首先通过RACE方法克隆得到白化相关基因tyrp1的2个转录本,进化树分析表明这2个转录本分别是tyrp1a和tyrp1b,利用RNAhybrid软件预测到mmu-143可能与tyrp1a基因存在互作关系,通过双荧光素酶实验初步验证了这一靶向关系。进一步的荧光定量结果显示,tyrp1a基因在正常牙鲆皮肤中的表达量显著高于白化牙鲆皮肤的表达量,正常牙鲆皮肤中mmu-143的表达量显著低于白化牙鲆皮肤中的表达量。本研究发现,牙鲆tyrp1存在2个转录本,分别是tyrp1a和tyrp1b。双荧光素酶实验和定量PCR分析初步证实,tyrp1a是mmu-143的靶基因,mmu-143是通过调控tyrp1a基因的表达来影响牙鲆白化的。此研究结果为深入揭示牙鲆白化发生的分子机制提供重要的基础资料。  相似文献   

Median Lethal Concentration (LC50) of Piscicidal Plants and Their Utilization in Aquaculture     

S. N. Ramanujam  R. Dominic 《Journal Of Applied Aquaculture》2013,25(4):326-333

Aqueous and ethanol extracts of Acacia pennata (bark), Catunaregam uliginosa (fruit), Diospyros lenceofolia (fruit), and Sapindus mukorossi (fruit) were evaluated as piscicides on the freshwater fish Danio dangila, Danio rerio, and Puntius shalynius, and the air-breathing Heteropneustes fossilis. Catunaregam uliginosa (fruit) possessed relatively higher piscicidal potency followed by Sapindus mukorossi (fruit), Acacia pennata (bark), and lastly Diospyros lanceofolia (fruit). Catunaregam uliginosa can thus be used for eradicating unwanted wild fishes in a short time span at low concentrations so that the health of aquatic environment is maintained.  相似文献   

东莞生态园湿地鱼类群落结构          下载免费PDF全文

李一帆  安建国  裴瑞华  吴鹏举  黄娜  王亚坤  丁盛  陈丽平  刘其根  胡忠军 《水产学报》2023,47(5):059311-059311

为了解东莞生态园湿地水域群落结构特征,探讨2种类型刺网(沉网和浮网)及不同网目网片渔获物组成的差异性,实验利用多网目(1.0、1.25、1.6、2.0、2.5、3.1、3.9、4.8、5.8、7.0、8.6和11.0 cm)单层刺网对该湿地的鱼类进行了调查。研究期间共采集到13种鱼类,相对重要性指数显示,海南似和莫桑比克罗非鱼为优势种,前者密度最高(占84.8%),后者生物量居多(40.2%)。渔获物物种组成沉浮网间差异显著,但单位努力捕捞数量(NPUE)、单位努力捕获重量(BPUE)及物种数与沉浮网间均无显著差异;海南似的NPUE在2种类型刺网间无显著差异,但莫桑比克罗非鱼和尼罗罗非鱼的NPUE浮网显著低于沉网。12个网目网片的渔获物物种聚成2类,1.0～2.0 cm网目网片渔获物聚为1类,海南似为指示种;2.5～11.0 cm片的聚为另1类,莫桑比克罗非鱼和尼罗罗非鱼为指示种。渔获物大小结构聚为2类,1.0～3.9 cm网目网片渔获物聚为1类,4.8～11.0 cm网目网片的聚为另1类。随着网目大小增加,渔获物平均体长线性递增,NPUE呈幂函数式下降。研究表明,为对内陆水域鱼类群落...  相似文献   

Protein and energy nutrition of brook trout (Salvelinus fontinalis) at optimal and elevated temperatures          下载免费PDF全文

M. N. Amin  C. G. Carter  R.S. Katersky Barnes  L. R. Adams 《Aquaculture Nutrition》2016,22(3):527-540

The digestible protein (DP) and digestible energy (DE) requirements for maintenance and growth of brook trout (Salvelinus fontinalis) were determined using a factorial model at either optimum (15 °C) or elevated temperature (19 °C). Several key parameters of the factorial model were measured using a series of inter‐related studies. The maintenance requirements for DP and DE were 0.10 gDP kg^?0.69 day^?1 (15 °C) and 0.31 gDP kg^?0.78 day^?1 (19 °C), and 34.86 kJDE kg^?0.84 day^?1 (15 °C) and 46.14 kJDE kg^?0.86 day^?1 (19 °C). The total requirements for DP were 0.10 gDP kg^?0.69 day^?1 + 2.14PG (protein gain) (15 °C) and 0.31 gDP kg^?0.78 day^?1 + 1.98PG (19 °C). The total requirements for DE were 36.86 kJDE kg^?0.84 day^?1 + 1.58EG (energy gain) (15 °C) and 46.14 kJDE kg^?0.86 day^?1 + 1.64EG (19 °C). The partial efficiencies for growth were 0.47 (15 °C) and 0.51 (19 °C) for protein, and 0.63 (15 °C) and 0.61 (19 °C) for energy. Nutrient gain was lower at the elevated temperature; however, feed formulation for brook trout should be adjusted to match changes in nutrient requirements at different culture temperatures. The protein and energy requirements model will be useful for developing commercial feeds and feeding charts for brook trout.  相似文献