Comparison of extractive components in muscle and liver of three Loliginidae squids with those of one Ommastrephidae species

Extractive components were determined for the mantle muscle and liver of three species of Loliginidae squid, Sepioteuthis lessoniana, Loligo bleekeri, and L. edulis, and one species of Ommastrephidae, Todarodes pacificus, as a control. Total free amino acid levels and the major free amino acids in muscle, taurine, proline, glycine, alanine, and arginine, were significantly higher in Loliginidae squids than in T. pacificus. The main nucleotide was adenosine 5′-monophosphate, which did not differ significantly between species. Malate was the organic acid found in muscle in highest concentrations. The muscle of these species contained a large amount of trimethylamine oxide. A large amount of glycine betaine was also detected in the muscle, but showed no large species difference. From these results, the muscle of Loliginidae species is considered to have a much sweeter taste than that of T. pacificus. Compared with muscle, squid liver was characteristic with high contents of taurine, glutamate, bitter amino acids, succinate, propionate, trimethylamine, and glycine betaine, and with low contents of sweet amino acids, arginine, nucleotides, malate, and trimethylamine oxide. These results suggest that squid liver is characterized by a complicated taste containing umami, bitterness, sourness, fishy flavor, and less sweetness.     

Correlation of extractive components and body index with taste in oyster Crassostrea gigas brands

Fisheries Science - We investigated the free amino acid (FAA) composition, glycogen content, and body index of 31 brands of oyster Crassostrea gigas to evaluate their taste graphically using a...     

Effect of raw materials on the extractive components and taste aspects of fermented fish paste: sakana miso

The suitability of various under-utilized fish species as starting material for the production of a miso-like fermented product was studied. To the end, four under-utilized fishes and shellfishes—spotted mackerel, lizard fish, horse mackerel, and common squid—were fermented, under either washed or unwashed conditions, with malt-rice (kome-koji) as a starter, and their quality parameters assessed. The protein content of the fermented fish pastes (18.1–22.4%) was superior to that of fermented soy paste (12.9%). Our analyses of other physico-chemical parameters of the finished products, including free amino acid, oligopeptide, organic acid, and mineral content, also revealed the potential utility of both washed and unwashed fish meat for the production of miso-like fermented fish pastes. Sensory evaluation revealed the potential of the washing step to produce a consistent product for large-scale production.     

Comparative study on extractive components of fresh and boiled gonads of three species of sea urchins from the Gulf of Thailand

Proximate compositions and extractive components of the gonads (roes) of three species of sea urchins, namely, Diadema setosum, Salmacis sphaeroides and Toxopneustes pileolus, from the Gulf of Thailand were identified and the boiling effect on these extractive components of these sea urchin roes studied. Of the three species tested, the gonads of D. setosum had the lowest moisture (62 %) and ash (2 %) contents and the highest protein (15 %) and lipid (11 %) contents. Major extractive constituents of the roes of D. setosum were taurine, arginine, lysine, glycine, tyrosine, valine, leucine, isoleucine, alanine, glutamic acid and inosine 5′-monophosphate; those for the roes of S. sphaeroides were glycine, lysine, alanine, arginine, ATP and adenosine 5′-diphosphate; those for the roes of T. pileolus were glycine, alanine, serine, ATP and adenosine 5′-monophosphate, respectively. Boiling in 3 % brine (98–100 °C, 2 min) drastically reduced the amounts of both free amino acids and ATP-related compounds of sea urchins belonging to all these species.     

Changes in extractive components and microbial proliferation during fermentation of fish sauce from underutilized fish species and quality of final products

To make use of underutilized fish species and produce high-quality condiments substitutable for those of mammalian origin, fish sauces were produced on a small industrial scale from three fish species, the flyingfish Cypselurus agoo agoo, the small dolphinfish Coryphaena hippurus, and the deepsea smelt Glossanodon semifasciatus, using salt and koji mold. During 180 days of fermentation, the pH decreased to approximately 4.5 and total nitrogen and free amino acids increased to approximately 2 g/100 mL and 6000 mg/100 mL, respectively. Halophilic and extreme halophilic bacterial counts dramatically increased from 10⁶ to 10⁸ colony forming units/mL between days 14 and 30 and decreased the reafter. In the final products, the pH and salt concentration decreased to between soy sauce and a Vietnamese fish sauce, Nuoc mam. The total amino acid and organic acid contents were almost the same as those of Nuoc mam and soy sauce. Sensory evaluation found these products to have lower smell, saltiness, and bitterness, and higher sweetness and umami taste than Nuoc mam. During fermentation, the histamine content increased in one or two of three fermentation tanks for each fish species. As a result, the histamine content of the final products was higher than that in Nuoc mam.     

Influence of storage temperatures and killing procedures on post-mortem changes in the muscle of horse mackerel caught near Nagasaki Prefecture,Japan

ABSTRACT:   The effect of storage temperature (0, 5, 10, and 15°C) and killing procedure (instant, struggled, temperature shocked, and spinal cord destruction killing) on post-mortem changes in the muscle of the horse mackerel caught near Nagasaki, Japan, was investigated. Temporal changes in adenosine triphosphate (ATP), inosine monophosphate (IMP), and lactic acid concentrations were slowest at 10°C storage temperature. The increase in K -values was slower at 10°C and below than at 15°C storage temperature. In addition, 10°C storage temperature was most suitable for maintaining a constant breaking strength value of the muscle. Regarding the effect of killing procedure, temporal changes in ATP, IMP, and lactic acid concentrations were slowest when killed by spinal cord destruction. The increase in K -value and the decrease in breaking strength were also slowest in the spinal cord destruction group. From these results, it was considered that storage at 10°C temperature and spinal cord destruction killing procedure were most effective in delaying post-mortem change in the horse mackerel.     

雌雄条纹锯(鱼旨)肌肉营养成分的比较与评价

本研究对雌雄条纹锯鮨(Centropristis striata)肌肉的营养成分进行了比较分析,并对其品质进行了评价与对比。结果显示,雌性条纹锯鮨肌肉中的水分极显著低于雄性(P<0.01),粗脂肪极显著高于雄性(P<0.01),粗蛋白质和灰分含量无显著差异(P>0.05)。雌雄条纹锯鮨肌肉中均检测出16种氨基酸,除蛋氨酸、赖氨酸和甘氨酸的含量具有显著性差异(P<0.05)外,其他13种氨基酸以及氨基酸总量(TAA)、必需氨基酸总量(EAA)和鲜味氨基酸含量(DAA)都不存在显著性差异(P>0.05)。依据氨基酸评分标准(AAS)和化学评分标准(CS)分值,雌雄条纹锯鮨肌肉的第一限制性氨基酸均为蛋氨酸,第二限制性氨基酸均为缬氨酸。雄性条纹锯鮨肌肉的必需氨基酸指数高于雌性,雌性为84.83,雄性为85.28。其必需氨基酸的组成比例均符合FAO/WHO标准。雄性条纹锯鮨肌肉的支链氨基酸和芳香族氨基酸的比值(F值)略高于雌性,雄鱼为2.28,雌鱼为2.24。雄性条纹锯鮨的单不饱和脂肪酸(MUFA)极显著高于雌性(P<0.01),多不饱和脂肪酸(PUFA)和EPA+DHA的含量差异均不显著(P>0.05)。雄性肌肉的∑n-3PUFA/∑n-6PUFA高于雌性,雄性为6.43,雌性为5.51。另外,雄性肌肉的钾钠比(K/Na)也高于雌性,雌鱼为8.27,雄鱼为14.27。研究表明,雄性条纹锯鮨比雌性具有更高的食用价值。     

基于渔获物统计的中国近海鱼类营养级结构变换及其与捕捞作业的关系

为了解我国东部海域(渤海、黄海和东海)和南海的鱼类生态结构和渔业资源变化特征,本研究在1983—2013年中国海洋渔船渔获统计数据的基础上,首先将渔获物中的鱼类按照营养级归类,然后计算其平均营养级(TL)和Fi B指数,并结合海洋捕捞作业方式,对鱼类的营养级结构长期变化进行分析。结果表明,在东部海域捕捞的25种主要鱼类渔获中,31年间TL呈现下降趋势,低营养层级鱼类比例增长了60%,中营养层级鱼类比例增长了129%,高营养级鱼类则下降了近51%;而在南海,31年间TL变化不明显,低营养级鱼类比例下降了6%,中营养级鱼类下降了43%,高营养级鱼类增长198%。东部海域和南海的渔获物鱼类生态结构变化说明,就营养级水平而言,东部海域近海渔业资源呈现明显的衰退现象,而南海则还未出现这种现象。     

Changes in some components of the muscle lipids of three freshwater fish species under natural extreme cold and temperate conditions

Fatty acid composition, conjugated linoleic acid and cholesterol contents in the muscles of three freshwater fish species (Barbus plebejus escherichi, Capoeta capoeta capoeta and Rutilus rutilus) were determined under natural extreme temperate (July) and cold (January) conditions. The aim of the study was to determine whether there were differences in these components of the muscle lipids among these three fish species under extreme natural conditions. Samples were analyzed using gas chromatography. Palmitic, oleic, docosahexaenoic and eicosapentaenoic acids were the predominant fatty acids in all fish in both months. The percentages of polyunsaturated fatty acids, n − 3 polyunsaturated fatty acids, n − 6 polyunsaturated fatty acids and eicosapentaenoic + docosahexaenoic acids in the muscle of B. plebejus escherichi and C. capoeta capoeta were significantly higher in January (P < 0.05) than in July. The ratio of n − 6 to n − 3 polyunsaturated fatty acids was lower than 0.60 in all fish species, with C. capoeta capoeta showing the lowest ratio in January (0.36). The levels of cholesterol and conjugated linoleic acid ranged from 103.46 to 150.10 mg/100 g oil and from 16.27 to 35.45 mg/100 g oil, respectively, for all samples in both months. There were no statistical differences in cholesterol levels among the three fish species in July and January. Conjugated linoleic acid contents were significantly higher in January in B. plebejus escherichi and C. capoeta capoeta. Of the three species tested, the extreme temperate and cold conditions affected B. plebejus escherichi the most.     

马氏珠母贝正常贝肉与黑壳病贝肉成分对比

为了研究黑壳病造成马氏珠母贝肉成份的变化,首先采用水蒸气蒸馏法分别提取正常马氏珠母贝和黑壳病马氏珠母贝肉的挥发性成份进行分析,正常马氏珠母贝肉检测出58种,黑壳病贝肉检测出59种。但黑壳病贝肉中仅有7种化合物与正常贝肉的挥发性成分相同。在黑壳病贝中,含量较高的成分有二十一烷和十八醛,分别为18.52%和17.95%,但在正常贝肉未检出。其次,采用茚三酮作柱后衍生试剂测定氨基酸的方法检测正常马氏珠母贝和患黑壳病的马氏珠母贝肉中牛磺酸的含量,结果分别为72.47mg/g、72.75mg/g,牛磺酸含量基本一致。通过分析黑壳病引起马氏珠母贝体内挥发性成分和牛黄酸成分变化,为研究马氏珠母贝患黑壳病的病变机理提供一定的科学依据。     

暗纹东方鲀饲料中豆粕替代鱼粉的营养生理效应及其与大豆抗原蛋白的相关性

选择体质量为(39.84±3.09)g暗纹东方鲀,分为8组,分别饲喂等氮等能的高鱼粉组、低鱼粉组、低鱼粉发酵豆粕组、低鱼粉豆粕组4组实用饲料和添加大豆抗原蛋白的半纯化饲料(大豆抗原蛋白含量分别为0%、5%、8%和12.5%),进行为期两个月的生长实验,探讨大豆抗原蛋白对暗纹东方鲀生长和生理生化的影响。结果显示,用发酵豆粕替代部分鱼粉的低鱼粉发酵豆粕组生长性能显著优于低鱼粉组,用豆粕替代部分鱼粉的低鱼粉豆粕组与低鱼粉组无显著差异。半纯化饲料中随着大豆抗原蛋白含量增加,生长率呈现先增后降趋势;实用饲料和半纯化饲料对肌肉组成有不同程度的影响;在肝脏丙二醛、总抗氧化能力和血清丙二醛指标中,低鱼粉豆粕组显著高于低鱼粉组,低鱼粉发酵豆粕组则与低鱼粉组无显著性差异,半纯化饲料系列在8%组出现峰值,显著高于其他组。低鱼粉豆粕组血清谷草转氨酶活性显著高于低鱼粉组,低鱼粉发酵豆粕组与低鱼粉组相比无显著性差异,半纯化饲料组谷草转氨酶和谷丙转氨酶呈现先增后减趋势。研究表明,与豆粕替代鱼粉相比,用发酵豆粕替代鱼粉更能促进鱼体生长;大豆抗原蛋白是影响豆粕替代鱼粉效果的重要因素,但对生长、抗氧化性能和生理生化指标的影响则因大豆抗原蛋白的含量与单独存在与否而异。     

Identification of alfonsino, Beryx mollis and B. splendens collected in Japan, based on the mitochondrial cytochrome b gene, and their comparison with those collected in New Caledonia

ABSTRACT:   The sequences spanning 307 bp of the mitochondrial cytochrome b gene were determined for 45 sepcimens of Beryx splendens and seven specimens of B. mollis collected in Japan, resulting in identification of 11 and three haplotypes in the two species, respectively. The parsimony tree was constructed from the determined sequences and those registered into the GenBank database as species A and W of B. splendens collected in New Caledonia, featuring with two clades. The first clade comprised species W from New Caledonia and B. mollis in the present study, whereas the second one contained species A from New Caledonia and B. splendens in the present study. These results demonstrate a large geographic distribution for both B. splendens and B. mollis. Some of the haplotypes found in Japan were identical to those of New Caledonia for both B. mollis and B. splendens , suggesting levels of gene flow at the trans -oceanic scale.     

Antagonism against fish pathogens by cellular components and verification of probiotic properties in autochthonous bacteria isolated from the gut of an Indian major carp,Catla catla (Hamilton)

Probiotic potential of the autochthonous bacteria in catla, Catla catla has been evaluated through determination of antagonistic activity (in vitro) of the cellular components of gut bacteria against seven fish pathogens. Altogether 208 strains were isolated, inhibitory activity of the isolates was evaluated through cross‐streaking and 16 primarily selected antagonistic strains were confirmed using the double‐layer method. Four bacteria that showed antagonism against ≥4 pathogens were selected as putative probiotics. The intracellular, extracellular, whole‐cell and heat‐killed cell components exhibited bactericidal activity against the pathogens. In addition, the selected strains were capable of producing different extracellular enzymes, competent to grow in intestinal mucus and could tolerate diluted bile juice. Analysis of 16SrRNA partial gene sequence revealed that both the strains CC1FG2 and CC1FG4 were Bacillus methylotrophicus (KF559344 and KF559345), while the isolates CC1HG5 and CC2HG7 were Bacillus subtilis subsp. spizizenii (KF559346) and Enterobacter hormaechei (KF559347) respectively. Bio‐safety evaluation through intra‐peritoneal injection of the isolates did not induce any pathological signs or mortalities in C. catla. The study confirmed probiotic properties of autochthonous gut bacteria in C. catla and demonstrated potential for using them as bio‐control agents. However, in vivo studies are essential to explore their efficacy in the commercial aquaculture.     

Interannual-decadal variability of demersal fish assemblages in the Tsushima Warm Current region of the Japan Sea: Impacts of climate regime shifts and trawl fisheries with implications for ecosystem-based management

Data sets for two bottom trawl fisheries, the coastal pair-trawler fishery and offshore single-trawler fishery in the Tsushima Warm Current (TWC) region of the Japan Sea, were compiled and analyzed for the last three decades (1974-2006). These data sets were used to (1) identify and compare the variability in demersal fish assemblages, and (2) relate these to water temperature to examine the impacts of climate regime shifts. Principal component analysis (PCA) of catches of target species in the two trawler fisheries showed synchronous decadal variability with step changes around 1986/1987 and 1996/1997. These step changes strongly suggest the effect of the late 1980s climate regime shift, which was characterized by an abrupt change from a cool to a warm condition in the TWC. The first and second principal components (PC1 and PC2) for both trawler fisheries agreed closely with winter and summer water temperature in the Japan Sea, respectively, suggesting PC1 (PC2) was associated with cold- (warm-) water species. However, between warm- and cold-water species the response pattern to water temperature was different. CPUE (catch per unit effort) of warm- (cold-) water species correlated positively (negatively) with water temperature, indicating the increase in water temperature has a positive (negative) effect on warm- (cold-) water species. Cold-water species decreased (increased) both in biomass and distribution during the warm (cold) regime, while warm-water species increased in biomass and/or distribution during the warm 1990s. These results suggested that the demersal fish assemblage structure changed abruptly as a consequence of the late 1980s climate regime shift. Impact of fishing was unclear on the demersal fish assemblage as a whole, but fishing pressure has been intensified for specific species under unfavorable climate regimes even with a declining fishing effort. Differing response patterns between warm- and cold-water species to climate regime shifts suggest the importance of integrated assessment and ecosystem-based management for the whole trawl fishery rather than only for individual target species.     

水产品养殖销售环节致病性弧菌污染状况和病原特征分析

该研究采用双层平板涂布法和划线法,从不同地区的海洋环境样品中分离纯化光合细菌,以副溶血弧菌 (Vibrio parahemolyticus)、创伤弧菌 (V. vulnificus)、鳗弧菌 (V. anguillarum) 为指示菌,采用牛津杯法测定海洋光合细菌菌株的抑菌作用,采用靛酚蓝分光光度法和盐酸萘乙二胺分光光度法测定不同菌株对氨氮 (NH₄ ⁺-N) 和亚硝态氮 (NO₂ ⁻-N) 的降解作用,筛选出具有抗弧菌并高效降解NH₄ ⁺-N和NO₂ ⁻-N复合功能的优良菌株。结果显示,从30个海水、海泥等样品中分离得到3株光合细菌,分离自连云港车牛山岛海水样品的菌株P-3,对3种弧菌均具有较强的抑制作用,其中对鳗弧菌的作用最强,抑菌圈直径为5.3 mm。3株光合细菌均具有一定的降解NH₄ ⁺-N和NO₂ ⁻-N作用,菌株P-3的降解作用最强,在含有50 mg·L⁻¹ NH₄ ⁺-N和NO₂ ⁻-N的培养基中培养4 d,降解率分别为89.68%和94.98%。经形态学观察、生理生化试验和16S rDNA序列分析,确定P-3为沼泽红假单胞菌 (Rhodopseudomonas palustris)。     

Dietary fish oil replacement with lard and soybean oil affects triacylglycerol and phospholipid muscle and liver docosahexaenoic acid content but not in the brain and eyes of surubim juveniles Pseudoplatystoma sp.

Triplicate groups of juvenile suribim were fed for 183 days one of four different isonitrogenous (47.6% crude protein) and isolipidic (18.7% lipid) diets formulated using three different lipid sources: 100% fish oil (FO, diet 1); 100% pig lard (L, diet 2); 100% soybean oil (SO, diet 3), and FO/L/SO (1:1:1, w/w/w; diet 4). The tissue levels of fatty acids 18:2n − 6 and 18:3n − 3 decreased relative to corresponding dietary fatty acid values. The 20:5n − 3 and 22:6n − 3 composition of muscle and liver neutral lipids were linearly correlated with corresponding dietary fatty acid composition. In contrast, the 22:6n − 3 composition of the brain and eye were similar among treatments. The 22:6n − 3 level was enriched in all tissues, particularly in the neural tissues. Similar results were observed for tissue polar lipids: fatty acids content reflected dietary composition, with the exception of the 22:6n − 3 level, which showed enrichment and no differences between groups. Given these results, the importance of the biochemical functions (transport and/or metabolism) of 22:6n − 3 in the development of the neural system of surubim warrants further investigation. M.D. Noffs and R.C. Martino dedicate this study to the memory of Prof. Dr. Luiz Carlos Trugo.     

Microbial and chemical properties of <Emphasis Type="Italic">aji-no-susu</Emphasis>, a traditional fermented fish with rice product in the Noto Peninsula,Japan

Aji-no-susu is a Japanese fermented fish product prepared from salted horse mackerel Trachurus japonicus, and cooked rice. We studied the organic acid and free amino acid contents and microflora in 12 aji-no-susu products to clarify their features as a lactic-acid-fermented food. Salinity of the samples was approximately 7.0% (rice portion) and 6.0% (fish portion) (w/w). Water activity was approximately 0.9, and pH was approximately 4.4 and lower. In the rice portions, lactic acid content was very high (57 mg/g sample). The predominant amino acids were alanine (2.3 mg/g rice portion) and lysine (2.1 mg/g). In the case of long-fermented (4 and 12 months) aji-no-susu, a high content of gamma-aminobutyric acid (GABA, 1.5 and 1.4 mg/g) was detected. Total viable counts in rice and fish portions were 7.7 and 7.4 log colony-forming units (cfu)/g, respectively. The number of lactobacilli in the rice and fish portions was 7.3 and 7.1 log cfu/g, respectively. Yeasts were detected in eight samples. Furthermore, acid-tolerant lactic acid bacteria (LAB) (Lactobacillus plantarum), GABA-producing LAB (Lactobacillus sp.), and halophilic or halo-tolerant yeast (Debaryomyces hansenii) were isolated and identified. Results in this study indicate that aji-no-susu is a typical traditional lactic-acid-fermented fish product.     

Comparison of the lipid profiles from wild caught eggs and unfed larvae of two scombroid fish: northern bluefin tuna (<Emphasis Type="Italic">Thunnus thynnus</Emphasis> L., 1758) and Atlantic bonito (<Emphasis Type="Italic">Sarda sarda</Emphasis> Bloch, 1793)

Lipids and essential fatty acids are determinants of the reproductive process in marine fish, affecting fecundity, egg quality, hatching performance, pigmentation and larval malformation. We have analyzed and characterized the lipids of eggs and unfed larvae of two wild caught scombroid fish, the Atlantic northern bluefin tuna (Thunnus thynnus) and Atlantic bonito (Sarda sarda). Dry matter and total lipid contents, polar and neutral lipid classes and total lipid fatty acid contents were determined in the eggs of bluefin tuna and eggs and unfed larvae during the development of Atlantic bonito. Bluefin tuna eggs had slightly but significantly more dry mass than bonito eggs but very similar lipid content. However, bluefin tuna eggs presented a higher polar lipid content due to increased proportions of phosphatidylethanolamine (PE), phosphatidylserine (PS) and phosphatidylinositol (PI). Bonito eggs and larvae showed increasing dry mass and decreasing lipid content with development. The proportion of polar lipids increased due to increased PE, PS and PI, whereas choline-containing polar lipids (phosphatidylcholine and sphingomyelin) remained relatively constant. Free cholesterol also increased, whereas the levels of other neutral lipids, especially triacylglycerol and steryl ester fractions, decreased, presumably due to utilization for energy to drive development. Bluefin tuna eggs had higher levels of n − 3 and n − 6 highly unsaturated fatty acids due to higher docosahexaenoic and arachidonic acid contents, respectively, than bonito eggs. The results are discussed in relation to the lipid and fatty acid requirements of larval scombroid fish in comparison to those of other larval marine finfish species under culture conditions.     

Effects of substituting dietary fish oil with crude palm oil and palm fatty acid distillate on growth,muscle fatty acid composition and the activities of hepatic lipogenic enzymes in snakehead (Channa striatus,Bloch 1793) fingerling

Three diets were formulated to be iso‐nitrogenous (450 g kg^?1), iso‐lipidic (65 g kg^?1) and iso‐energetic (18.5 KJ g^?1), varying only in their lipid sources and designated as 100% fish oil (FO), 100% crude palm oil (CPO) and 100% palm fatty acid distillate (PFAD). Feed were hand fed to homogenous groups of 12 Channa striatus fingerlings (mean weight 3.5 ± 0.3 g) per tank in triplicate for 12 weeks, in a recirculation system. The growth performance and feed intake in the CPO and PFAD treatments were significantly (P<0.05) higher than those in the fish fed the control diet (FO), respectively, whereas the feed conversion ratio was better in PFAD than that in the other treatments respectively. The biological indices monitored (hepatosomatic index and viscerosomatic index) as well as carcass yield did not vary significantly among all the treatments respectively. The muscle fatty acid (FA) profile of fish was influenced by the composition of the diets fed, whereas no differences were recorded in the activities of the hepatic lipogenic enzymes monitored (fatty acid synthetase, citrate cleavage enzyme and malic enzyme). Whole‐body proximate composition analysis revealed that PFAD treatment, compared with others, contained significantly higher protein and ash, but lower lipid contents, although the muscle content of these nutrients was similar among all the treatments. Based on the results of this trial, CPO and PFAD could be used to partially substitute FO in the diet for C. striatus fingerling, to achieve good growth performance without any negative effects or compromising the muscle n‐3 FA composition (especially in the docosa hexaenoic acid and eicosa pentaenoic acid content).