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1.
ABSTRACT: Of the free, conjugated and bound forms of polyamines, the free form of spermidine was the most abundant polyamine in Heterosigma akashiwo throughout the growth period except for the lag phase. Free spermidine content increased remarkably during the exponential growth phase and increased as the growth rate increased. The maximum growth yield of H. akashiwo was reduced by the addition of methylglyoxal bis-guanylhydrazone (MGBG) and the reduced growth yield could be counteracted by the addition of spermidine to the medium. It is concluded that spermidine plays a significant role in the growth of H. akashiwo . These results are similar to those obtained in Chattonella antiqua that belongs to same taxonomic Class as H. akashiwo . 相似文献
2.
S. J. Laly Jeyakumari Annamalai K. Ashok Kumar T. V. Sankar Lalitha KV George Ninan 《Journal Of Aquatic Food Product Technology》2019,28(2):221-232
Sutchi catfish (Pangasianodon hypophthalmus) is a highly preferred farmed species that is produced in huge quantities. Meat from ice-stored (4 ± 2°C) whole Sutchi catfish was evaluated for formation of biogenic amines, such as putrescine, cadaverine, histamine (HIM), agmatine, tyramine, spermine, and spermidine, and compared with biochemical, microbial, and sensory attributes during 22 days. Analysis of content of biogenic amines in the meat was carried out by liquid chromatography with tandem mass spectrometry using a without derivatization method. Three amines, namely, tyramine, spermidine, and spermine, were only present on 0th day of storage. Presence of cadaverine was noticed from 9th day onwards, where the aerobic plate count (APC) reached 4.85 log CFU/g. Putrescine was detected on the 22nd day of storage, where the APC crossed 7 log CFU/g. HIM was detected in lower quantities from 3rd day onwards. A shelf life of 15 days was determined based on sensory and microbiological evaluation. Although the samples were biochemically acceptable throughout the storage period, APC exceeded the limit on day 19, and the gradual increase of H2S-producing bacteria, Brochothrix thermosphacta, Aeromonas, and Enterobacteriaceae, was observed during storage. 相似文献
3.
To determine the changes in blood chemistry associated with sequential transfer of summer flounder Paralichthys dentatus (320–480 g), 300 hatchery-reared fish were moved to three different environmental conditions during a 20-d period. Fish were transferred in progression from a recirculating seawater system (22 ppt, 22.5 C) to a flow-thru seawater system (31 ppt, 20.0 C), to three small coastal net pens (33 ppt, 15.5 C), and finally to a large open ocean net pen (33 ppt, 16.0 C). For this study, eight random fish were captured at each progressive step (environmental condition), anesthetized (MS222), and bled from the caudal vein (2 mL). Transferred flounder were bled every 12 h for 48 h to collect plasma cortisol and glucose samples. Fish were bled 24 h after transport and every 3 d thereafter for osmolarity, hematocrit, hemoglobin concentration, mean corpuscular hemoglobin content, glucose, cortisol, and the electrolytes Cl- Na+ , K+ and Ca+ . The most significant perturbations to blood chemistry (P < 0.05) occurred within 24 h of initial transfer from the recirculating to flow-thru seawater systems, suggesting an osmoregulatory rather than handling or transfer related stress. Osmolarity, electrolyte, and hematological parameters fluctuated and then recovered to stable levels by day 8 in the flow-thru seawater system. However, unlike the initial transfer, successive movement to the coastal and then the open ocean net pens produced transient increases in both plasma cortisol and glucose levels, suggesting a high level of stress associated with extended flounder handling and transfer. 相似文献
4.
分析了乌鳢(Channaargus)即杀后背肉、腹肉、尾部肉、肝脏、生殖腺中ATP关联化合物、游离氨基酸、多胺、糖元及糖酵解中间代谢物、有机酸等的含量。ATP关联化合物在肌肉中的总量为7.5～8.0μmol·g-1。ATP在背肉含量为3.9μmol·g-1,腹肉为4.1μmol·g-1,尾部肉为4.7μmol·g-1。运动激烈的尾部肉ATP占63%,含量相当高。肝脏中有少量的腺苷与肌苷酸一起被检出,据此可认为ATP的分解存在两个途径。游离氨基酸总量在背肉中为436.0mg·(100g)-1,腹肉中为405.0mg·(100g)-1,尾部肉中为356.3mg·(100g)-1。牛磺酸和甘氨酸为主要氨基酸,占68%～73%。丙氨酸和谷氨酸也相当高的含量检出。肌肉中的多胺检出为精胺和亚精胺,肝脏和生殖腺中有较高浓度的腐胺及亚精胺和精胺检出。即杀后糖元的量约占肌肉的0.5%,还有相当多的葡萄糖和6磷酸葡萄糖的糖酵解中间代谢物以及其最终产物乳酸的大量检出。 相似文献
5.
George Vardanis Liliana Sfichi‐Duke Lluis Tort Pascal Divanach Kiriakos Kotzabasis Michail Pavlidis 《Aquaculture Research》2011,42(3):341-350
The freshness of red porgy slaughtered in ice slurry and stored in melting ice was evaluated instrumentally, biochemically and sensorialy. Additionally, postmortem skin colour changes were monitored, in an attempt to demonstrate the use of chromaticity parameters as a reliable and convenient approach to quality assessment. Dielectric properties showed a statistically significant decrease (P<0.05) from 12±0 on day 0 to 7.85±0.31 on day 7; there was also a significant decrease in muscle polyamines with more than two amino groups (spermidine and spermine) and an increase in the di‐amine putrescine. The sensorial score was significantly decreased from 30±0 to 4.33±0.21 on day 7. Minimal lightness (L*) and hue (H°ab) at the dorsal skin area were observed on days 1 and 3 following harvesting. Finally, there was a marked decrease in the entire colour index (ECI – a combination of skin hue and chroma) of both the dorsal and the ventral area in day 3 onwards to day 7, as well as a statistically significant correlation between all the estimated freshness indices and ECI. Based on all these, we inferred that the total polyamines (or putrescine to spermidine and spermine ratio) and ECI could be reliable estimators of freshness, at least under the experimental conditions applied. 相似文献
6.
龙须菜在网箱养殖区的生物修复研究 总被引：4，自引：0，他引：4
在福建省东山县八尺门网箱养殖区的浅水区吊养面积约0.7 hm2的龙须菜(Gracilaria lemaneiformis),研究龙须菜对网箱养殖区水质的修复效果。通过对实验区及其内外两侧的定点监测,以及对与潮流方向一致和垂直的2个断面的监测,结果表明,修复区的溶解氧(DO)浓度明显高于非修复区,无机氮(IN)、无机磷(IP)浓度低于非修复区,由此可见,通过海水交换,龙须菜可以吸收流经修复区的IN、IP,并提高流出修复区的海水的DO水平。这有利于改善网箱养殖区的海水水质,提高网箱养鱼的成活率和生长率,促进海水养殖的可持续发展。[中国水产科学,2007,14(3):488-492] 相似文献
7.
Ms. S. Hasegawa T. Hirano T. Ogasawara M. Iwata T. Akiyama S. Arai 《Fish physiology and biochemistry》1987,4(2):101-110
The osmoregulatory ability of chum salmon (Oncorhynchus keta), reared in fresh water for a prolonged period, was examined by transferring them directly to seawater and then back to fresh water. When fry and juveniles weighing 0.3–125g, reared in fresh water for 1.5–13 months, were transferred directly to seawater, they adjusted their plasma Na+ concentration to the seawater-adapted level within 12–24h. When they were transferred back to fresh water after having been adapted to seawater for 2 weeks, the plasma Na+ level gradually decreased during the first 12–24h, and then increased to reattain the initial freshwater level after 5–7 days. No mortality was observed during the experiment except among the smallest fry weighing about 0.3g after transfer to seawater (2.1%). The maintenance of good osmoregulatory ability of the chum salmon for a prolonged period in fresh water seems to be unique among Pacific salmon, with the possible exception of the pink salmon.Changes in plasma levels of hormones during the transfer experiments were recorded in juveniles reared in fresh water for 13 months. Prolactin levels increased maximally 3 days after transfer from seawater to fresh water, as would be expected from its well-established role in freshwater adaptation in several euryhaline teleosts. In addition, an increase in plasma growth hormone was observed during the first 12h after seawater transfer, along with a tendency towards a decrease during freshwater transfer, suggesting an important role for this hormone in seawater adaptation. There were no consistent changes in plasma levels of thyroxine and cortisol during freshwater to seawater or seawater to freshwater transfer. 相似文献
8.
ISAO TAKAHASHI KENSAKU AZUMA SHINJI FUJITA IZUMI KINOSHITA HIROYUKI HIRAGA 《Fisheries Science》2003,69(3):438-444
ABSTRACT: Larval and juvenile ayu from seven year-groups (1986, 1987, 1992, 1995, 1996, 1999 and 2000) were collected in the Shimanto Estuary and adjacent coastal waters. The present study focuses on the variation among year-groups in the hatching period estimated by age determination using the otolith. The hatching period of the dominant cohorts in the 1986, 1987 and 1992 year-groups occurred from late October to mid-November. A delay of the hatching period of the dominant cohort was observed from the 1995 year-group, which occurred in late November to early December, and the dominant periods in the 1996, 1999 and 2000 year-groups were observed from early to late December. It appears that the delay of the hatching period of dominant cohorts was not due to a delay of spawning, but a high mortality of early hatched larvae. The water temperature in autumn in the coastal waters adjacent to the Shimanto River has tended to rise over the past 20 years and this trend was especially notable in the late 1990s. The delay in the hatching period of the dominant cohort observed from the 1995 year-group was likely to be related to the rise in seawater temperatures in autumn. 相似文献
9.
10.
Manh Hung Pham Jean‐Dominique Durand Minh Phong Le Bich Thao T. Vo Duc Huy Hoang Jacques Panfili 《水产资源保护:海洋与淡水生态系统》2020,30(8):1626-1637
- 1. Marine protected areas (MPAs) are set up to conserve biodiversity, but their design is not always based on strictly scientific considerations. Ideally, an MPA should protect all key habitats necessary for a marine species to complete its life cycle. The identification of these key habitats is complex, especially during the early life of marine fishes.
- 2. A widely distributed tropical and important low trophic‐level fish species, Spratelloides delicatulus (Clupeidae), was used to evaluate the significance of various coastal habitats for its larvae and juveniles in the Con Dao Archipelago MPA in Vietnam. Early stages (larvae and juveniles) were sampled monthly over one year (June 2016 to May 2017) using light traps in three main habitats (seagrass beds, coral reefs and harbour). The species was identified using morphometry and DNA barcoding. Age and growth variables were estimated using otolith daily growth increments.
- 3. A total of 3,581 fish were caught. The species was not found in captures between January and February, directly linked to the decrease in seawater temperature and was most abundant from April to June. For a subsample of 248 fish (7–38 mm standard length), ages ranged from 7 to 108 days.
- 4. Captures and back‐calculated birthdates using otolith daily increments showed that S. delicatulus spawns during the period of high seawater temperature, from March to October. The species colonizes all three habitats during the early stages (0–26 days old), with growth rate lowest on the seagrass beds. Nevertheless, the species occupies seagrass beds exclusively during the older stages.
- 5. The conservation of seagrass beds in the Con Dao archipelago is essential for protection of juvenile stages of this species but this habitat is presently not included in the MPA patches. Establishment of a continuum of protected areas linking habitats, rather than the existing patches is needed to conserve the complete life cycle of this species in the Con Dao MPA.
11.
The present work reports the activities of urea cycle enzymes during the ontogenic development of the teleost pacu (Piaractus mesopotamicus). Urea cycle enzymes from the kidney and liver of adult fish were compared with those from the fish's embryonic phases. Samples
were evaluated over all phases of embryonic development, the larval period and alevin. Ammonia and urea concentrations were
determined during embryogenesis and in the plasma of adult fish. Except for carbamoyl phosphate synthetase-III (CPS-III),
all enzymes of the urea cycle were expressed in the larvae and alevins as well as in the liver and kidney of adult fish. In
spite of the low level of activity of the ornithine urea cycle (OUC) enzymes compared to those in mammals, and the low levels
of tissue urea concentration compared to ammonia, the ureogenesis was evaluated in pacu. Ammonia seems to be the main nitrogenous
waste during embryonic development. In this phase glutamine synthetase (GS) may play a role in ammonia detoxification, and
the OUC enzymes can be individually involved in functions other than urea production. The presence of ornithine carbamoyl
transferase (OCT) in all developmental phases of pacu and in the adult liver and kidney suggests that this enzyme is performing
different metabolic pathways. OCT in the kidney, wherein the activity is less than in the liver, should work in the biosynthesis
of polyamines and control the arginine plasma concentration given that renal arginase and argininosuccinate synthetase-argininosuccinate
lyase are more active than from the liver. We suppose that OCT during the embryogenesis is a control step regulating the cellular
concentration of ornithine for polyamines synthesis. 相似文献
12.
Effects of feeding Atlantic salmon (Salmo salar L.) imbalanced levels of lysine and arginine 总被引：2，自引：0，他引：2
Two experiments were performed to study the effects of imbalanced levels of arginine and lysine in diets of Atlantic salmon ( Salmo salar L.) with Zein as the major dietary protein source. In the first experiment, the effects of high levels of lysine on marginal levels of arginine and high levels of arginine on marginal levels of lysine were compared in fish fed these amino acids at either marginal or high levels. Dietary contents of arginine/lysine were 30.0/29.4, 17.0/29.4, 30.0/14.4 and 17.2/14.5 g kg–1 , respectively. In the second experiment, fish were fed increasing levels of lysine in a diet containing arginine at the requirement level. Dietary levels of arginine/lysine in the second experiment were 23.0/17.0, 23.0/34.3, and 23.0/46.4 g kg–1 .
Atlantic salmon fed marginal levels of lysine showed better growth and feed utilization when fed diets supplemented with high levels of arginine. Fish fed diets marginal in arginine exhibited increased growth and feed utilization when fed diets supplemented with high levels of dietary lysine. Increasing dietary lysine did not significantly affect growth in fish fed arginine at the requirement level. Increased growth in fish fed high dietary arginine levels might be explained by increased tissue concentrations of ornithine acting as a precursor for in situ synthesis of polyamines. A slight correlation between specific growth rate (SGR) and concentration of spermidine in muscle and between condition factor and concentration of total polyamines in muscle was seen. Abdominal injection of U-C14 arginine may indicate lysine inhibition of arginine availability in muscle tissue. 相似文献
Atlantic salmon fed marginal levels of lysine showed better growth and feed utilization when fed diets supplemented with high levels of arginine. Fish fed diets marginal in arginine exhibited increased growth and feed utilization when fed diets supplemented with high levels of dietary lysine. Increasing dietary lysine did not significantly affect growth in fish fed arginine at the requirement level. Increased growth in fish fed high dietary arginine levels might be explained by increased tissue concentrations of ornithine acting as a precursor for in situ synthesis of polyamines. A slight correlation between specific growth rate (SGR) and concentration of spermidine in muscle and between condition factor and concentration of total polyamines in muscle was seen. Abdominal injection of U-C
13.
《水生生物资源》1999,12(5):335-342
Bioassays were carried out with the `blue diatom' Haslea ostrearia Simonsen, which is responsible for oyster greening during the fattening period of Crassostrea gigas Thunberg in oyster ponds. Samples of seawater were taken from two oyster ponds: one without oysters and the other with 20 oysters per m[sup2 ], maximal density allowed by the French AFNOR norm for `refinement'. The aims were to clarify the nutrient requirements of this diatom, also to elucidate the eventual influence of C. gigas at this density on the seawater fertility and to envisage the mass production of this diatom by pond fertilization. Examination of cell numeric densities at the end of bioassays allows us to conclude that silicate was the first limiting nutrient, closely followed by phosphate. Chlorophyll a concentrations led to different conclusions: phosphate was the first limiting factor, but after the seawater storage period in ponds, seawater quality evolved to a deficiency of nitrogen. Silicate addition increased cell division rate, and silicate depletion increased chl a synthesis for this species. Examination of nutrient assimilation ratios confirms that H. ostrearia requires a large amount of silicon. From these results, it was possible to prepare a N + P + Si simplified medium which has been tested in laboratory and field mesocosm conditions. In both conditions, similar results were observed: a significant increase in H. ostrearia cell concentrations and consequently an evolution up to the greening stage. Applications of this work are numerous; the principal permits us to envisage the production of this species in 25-m3 ponds, with the aim of allowing constant production of the greening phenomenon. 相似文献
14.
为了解大亚湾海域海水中氮(N)、磷(P)营养盐的时空分布情况及富营养化程度,于2009年4月和5月、2010年5月和6月、2012年2月、2015年1月和2月对大亚湾海域进行海水采样监测。结果表明,大亚湾海域不同功能区无机氮(DIN)和活性磷酸盐(PO4-P)浓度总体上为先增后降的趋势,DIN和PO4-P的时空分布由于受陆源污染、海水养殖等影响,浓度呈近海岸向远海岸递减的趋势。潜在富营养化评价表明,大亚湾海域整体上经历了由贫营养转为中度营养再转为贫营养的过程,其中一类功能区长年处于贫营养状态。总体上大亚湾平均氮磷比(N/P)接近或小于Redfield比值。 相似文献
15.
Plasma and liver vitamin E concentrations in a population of farmed Atlantic salmon, Salmo salar L., fed commercial diets were measured by high-performance liquid chromatography. In healthy fish fed diets containing 160-210 mg kg?1all-racα-tocopheryl acetate, vitamin E accumulated in the liver and plasma. Over a 20-month period, beginning 4 months prior to seawater transfer, mean vitamin E concentrations ranged from 51 to 754 μg g?1 wet tissue in liver and from 7 to 68 μg mL?1 in plasma. In liver, a sharp increase in vitamin E concentrations was recorded between 6 and 10 weeks after transfer. In plasma a similar increase occurred between 4 and 5 months post transfer. Total lipid and polyunsaturated fatty acid concentrations were also measured in these tissues. Liver total lipid concentrations fell during the period of smoltification, but there was no relationship between vitamin E and either total lipid or total polyunsaturated fatty acid concentrations in liver or plasma. 相似文献
16.
Takashi Yoshikawa Kenichi Kanemata Gentoku Nakase Mitsuru Eguchi 《Fisheries Science》2017,83(4):635-647
The possible impacts of resuspension of low-density bottom sediments on the microbial decomposition process of organic matter were investigated at a coastal fish farming area. Hydrolysis and mineralization rates were much higher in sinking particles, resuspendable particles, and bottom sediments than in seawater. The cell-specific mineralization rate of free-living bacteria in seawater was several times higher than that of particle-associated bacteria at the other three sites. Conversely, no significant difference was observed in the cell-specific ecto-enzymatic hydrolysis rate. These results indicated different strategies in the utilization of organic matter: free-living bacteria actively respire low-molecular-weight compounds produced from the high-molecular-weight compounds resulting from extracellular enzyme activity of particle-associated bacteria. Both hydrolysis and mineralization were higher in sinking particles than in the other three sites. Hydrolysis rates were higher in resuspendable particles than in bottom sediments. Furthermore, leucine aminopeptidase and mineralization rates tended to be highest during winter in all four sites within the water column. These results suggest that the microbial decomposition of organic matter is stimulated by the resuspension of bottom sediments, especially during winter, when vertical mixing is relatively strong. 相似文献
17.
SUMMARY: Aoshio is hypoxic milky blue-green seawater observed in some eutrophic bays. Previous studies have shown that colloidal sulfur causes the coloration and that the source of aoshio water is attributed to coastal anoxic bottom water. Occurrences of aoshio have been reported in limited areas of coastal seawater, although hypoxic transparent water seems rather universal. Promotion in auto-oxidation of sulfide by metal ions in seawater was investigated to explain the occurrences of aoshio. Artificial seawater containing 10 μM metal ion was assayed for the sulfide oxidation rate. The velocity constant which represents the oxidation rate within the initial 30 min and the amount of reacted sulfide in 2 h were determined by oxygen monitoring and sulfide quantification, respectively. Fe2+ and Cu2+ enhanced the initial 30 min reaction. Fe2+ , Fe3+ and Ni2+ increased the amount of reacted sulfide in 2 h, forming whitish turbid water. Seawater from a suspected source of aoshio water was also assayed for the auto-oxidation rate of sulfide. The oxidation rate in water from 12 m depth was 13–19 times higher than the artificial seawater without an addition of heavy metal ions. More than 15% of the oxidation rate in 12 m deep seawater was explained by dissolved iron in the seawater. 相似文献
18.
Arne M. Arnesen Even H. Jørgensen Malcolm Jobling 《Fish physiology and biochemistry》1993,12(4):281-292
The purpose of the current study was to examine seasonal changes in seawater tolerance and growth performance of anadromous
Arctic charr (Salvelinus alpinus L.) held at the same temperature (8°C) during winter and summer. Charr (20–27 cm), previously reared in freshwater under
natural photoperiod, were transferred either directly (DT) from freshwater to seawater (35 ppt), from freshwater to brackish
water (20 ppt), or were gradually adapted (GT) to seawater over a period of 10 days. Control fish were held in freshwater.
Feed intake and osmoregulatory ability were then monitored on three occasions during the following 59 days. Two experiments
were carried out, one during winter (December–January) and the other during summer (June–July). In both experiments fish mortality
was low. Plasma osmolalities recorded in fish transferred to seawater were within normal ranges, but osmolalities on day 10,
were significantly lower in summer (313 mOsm/kg (DT), 328 mOsm/kg (GT)) than in winter (323 mOsm/kg (DT), 352 mOsm/kg (GT)).
In winter, feed intake and growth rates were high in fish kept in fresh and brackish water, but charr transferred directly
to seawater ate little and lost weight. Fish that were gradually adapted to seawater occupied an intermediate position. During
summer the observed differences in feed intake were small and all fish had relatively high growth rates. These results suggest
that Arctic charr display seasonal changes in feed intake and growth performance that parallel seasonal changes in hypoosmoregulatory
capacity. The ability to survive and hypoosmoregulate in full strength seawater does not, however, seem to be a particularly
good indicator of successful seawater adaptation with respect to the ability to display high rates of feed intake and growth.
During winter, a gradual transfer to seawater appeared to lead to improved feeding and growth compared to direct transfer. 相似文献
19.
20.
ABSTRACT: The release of zoospores from zoosporangia in Laminaria japonica mainly occurred at night. The maximum swimming speed of the zoospores was observed immediately after release (~160 μm/s), and then decreased with time. The zoospores exhibited clear chemotaxis to high concentrations of nitrate-N and phosphate-P. Only half of the zoospores were observed to swim against seawater with a flow velocity of 124 μm/s. The zoospores became floating spores after they stopped swimming in the seawater. Low light and low water temperature conditions prolonged the swimming period of the zoospores. However, the photosynthesis of the zoospores was suppressed in low water temperatures, and was also limited under high light irradiance. These results suggest that photosynthesis in zoospores does not prolong their swimming period, and that when their swimming energy is exhausted, floating spores appear. 相似文献