Muscle Of Red Sea Bream Research Articles

Nutritional Supplementation and Enhanced Antioxidant Function by Dietary Intake of Selenoneine and Other Selenium Compounds in Red Seabream Pagrus major

Selenoneine, 2-selenyl-Nα, Nα, Nα-trimethyl-L-histidine, is the major organic selenium compound in marine fish. To characterize biological antioxidant function of selenoneine in fish, the accumulation of selenoneine and other selenium compounds, i. e., sodium selenite and selenomethionine, in the muscle and other tissues of red seabream. We reared red seabream by feeding of 1% dry pellet containing of sodium selenite, selenomethionine, or selenoneine of body weight twice a day for 4 weeks. After that, we replaced to 1% of normal commercial dry pellet of body weight twice a day for 1 week from the selenium supplementation, and tissue distribution of total selenium was determined. Selenium supplementation with selenoneine, selenomethionine, and sodium selenite enhanced selenium accumulation in the white muscle, kidney, and hepatopancreas in comparison with the control group. By the dietary intake of selenoneine, total selenium concentrations were increased in the white muscle, heart, kidney, spleen, hepatopancreas, brain, and blood cells in a dose-dependent manner during the trials after 2 weeks. Dietary intake of selenoneine as well as sodium selenite and selenomethionine reduced oxidation–reduction potential (ORP). Selenoneine concentrations in the white muscle and blood cells were accumulated for 4 weeks by the selenoneine intake, whereas selenoneine concentration was not elevated by the intake of selenomethionine and sodium selenite, suggesting that tissue selenoneine levels might be derived from only selenoneine-containing diet. The uptake factor of selenoneine from the artificial feed containing selenoneine was calculated to be 0.0062 in the white muscle and 4.0 in the blood. The half-life of total selenium in the blood cells and white muscle were estimated to be 60 days in the white muscle and 30 days in the blood.

Analysis of metabolites of red seabream (Pagrus major) from different geographical origins by capillary electrophoresis time-of-flight mass spectrometry.

Red seabream (Pagrus major), a migratory fish, is characterized by high protein levels in the muscle. South Korean and Japanese red seabreams have a general distribution pattern; however, distinguishing them based on their geographical origin is difficult. In this study, we used capillary electrophoresis time-of-flight mass spectrometry (CE-TOF/MS) to analyze the red seabream muscle metabolome to investigate how can distinguish the origin of the fish. The metabolites were extracted using 50% acetonitrile in water. Chromatographic separation was successfully used to classify the metabolite profiles of Japanese and South Korean red seabream. Principal component analysis and hierarchical cluster analysis showed good ability to categorize the samples according to their origin. Amino acids showed the greatest quantitative difference in South Korean and Japanese muscle samples. Specifically, the L-alanine, L-glutamic acid, L-isoleucine, dimethylglycine, and L-valine levels in Japanese red seabream samples were significantly higher than those in South Korean samples. In contrast, the levels of trimethylamine N-oxide and inosine monophosphate in South Korean muscle samples were significantly higher than those in Japanese red muscle samples. The monitored metabolite profiles suggest that South Korean and Japanese red seabreams can be identified on the basis of amino acid levels.

Tissue inhibitor of metalloproteinase-2 (TIMP-2) from red seabream (Pagrus major): Molecular cloning and biochemical characterization of highly expressed recombinant protein

The tissue inhibitor of metalloproteinase-2 (TIMP-2) is originally characterized as an endogenous inhibitor of matrix metalloproteinases (MMPs) to response collagenolysis associated with immune challenge. In this study, the cDNA encoding TIMP-2a gene from red seabream (Pagrus major) muscle was cloned. It was 585 bp encoding a putative protein of 194 amino acids, which comprised all recognized functional domains and showed the high identity to TIMP-2as from other teleost fishes, revealing it belongs to TIMP-2a family. Soluble rTIMP-2a was efficiently expressed using a new constructed pPIC9K-rTIMP-2a vector with high inhibitory activity against to MMP-2 and MMP-9. The recombinant TIMP-2a tagged with 6 histidine residues showed the molecular mass of 23 kDa and isoelectric point of 6.50. Furthermore, the 6 disulfide bonds formed by 12 conserved cysteine residues were identified as functional motifs for its structural stability. In addition, rTIMP-2a possessed the high inhibitory activity against gelatinolytic hydrolysis and degradation of type I collagen which induced by endogenous MMPs in muscle. The results revealed the properties and inhibitory function of rTIMP-2a, which may be a pivotal role in regulation gelatinolytic MMPs metabolization during defense mechanism.

Long-term stability of RNA isolated from muscle of red seabream (Pagrus major) during ice storage.

Recovering high-quality intact RNA from postmortem tissue is of major concern for gene expression studies. However, it is difficult to perform RNA extraction from aquacultured fish immediately after death, as rapid and accurate skills are needed for the procedure. The objective of this study was to quantitatively assess the integrity of total RNA extracted from muscle, liver, and digestive tract tissues of red seabream stored in ice as whole bodies, at a range of time points up to 10days postmortem, using RNA integrity number (RIN) and quantitative PCR (qPCR). The RIN of total RNA in muscle remained over 8.0 for 5days postmortem. The RINs in the liver and digestive tract were under 5.0 at 2days postmortem. The mRNA levels of tissue inhibitor metalloproteinase 2 (TIMP-2) and β-actin, measured using qPCR in muscle, decreased to 87.8% at 1day postmortem and to 45.5% at 2days postmortem, from that at 0days postmortem. In the liver and digestive tract, the mRNA levels were not significantly changed until 1day postmortem. These results indicate that RNA, especially from fish muscle, can be maintained at high quality for several days postmortem solely by storing the fish body in ice.

Effects of olive leaf powder supplemented to fish feed on muscle protein of red sea bream.

Olive leaf is known to have the high polyphenol content of 6-9% in dry weight. We investigated the effects of olive leaf powder (OLP) supplemented to fish feed on muscle protein of red sea bream (Pagrus major). Fish reared with feed containing 8% OLP for 40days had 1.4 times higher myofibril content and 2.2 times higher acid-soluble collagen content than fish reared with control feed for the same period. On the other hand, sarcoplasmic protein content and collagenase activity of the muscle were almost the same between the control fish and OLP-diet fish. Microstructure observation of fish muscle showed that OLP-diet fish has more rigid endomysium structure than that of the control-diet fish. Since collagen fiber in endomysium is responsible for the texture of the muscle, feeding OLP to aquaculture fish will lead to a harder muscle texture. The present study suggests that OLP is a useful feed additive to enhance the texture of aquaculture red sea bream muscle through strengthening of the collagen structure in the muscle.

Proteolytic degradation of myofibrillar components by endogenous proteases in red sea bream muscle

Proteolytic degradation of myofibrillar components by endogenous proteases in red sea bream muscle

ROLES OF APOPTOSIS AND AUTOPHAGY ON THE TEXTURE OF RED SEA BREAM MUSCLE

One of commercial brands in farmed-products of red sea bream (Pagrus major), named “Date-Madai”, is known to possess hard texture and transparency when served as “Sashimi”. The quality of “Sashimi” is usually evaluated by texture, appearance, and color of dark muscle. These characters easily change worse during post mortem storage. The aim of this study was to reveal relationship between proteolytic degradation and muscle quality of the red sea bream. Sensory analysis was carried out to evaluate the quality of “Sashimi” in terms of texture and appearance of flesh. Western blot analysis was conducted to evaluate protein expressions of red sea bream muscle. Significantly higher score in the sensory analysis for brightness was given to the “Date-Madai”. Similar tendency were also observed in color, texture and general acceptability. Intracellular effector of the apoptotic pathway includes contributin of caspase family. Lower level in caspase-3 protein was observed in the “Date-Madai” muscle. Autophagy is known to be inhibited by the target of rapamycin (TOR) signaling. Phosphorylated ribosomal protein S6 kinase, which is in the downstream of the TOR, increased in the “Date- Madai” muscle. This study concluded that the apoptosis and autophagy could be associated with the quality of the red sea bream. Keywords: apoptosis, autophagy, proteases, red sea bream

Effect of seasonal variation in seawater dissolved mercury concentrations on mercury accumulation in the muscle of red sea bream (Pagrus major) held in Minamata Bay, Japan

Japanese stingfish (Sebastiscus marmoratus) and Bambooleaf wrasse (Pseudolabrus japonicas) are monitored annually for mercury pollution in Minamata Bay, Japan. The average total mercury concentration in the muscle of these two species in Minamata Bay was 0.36 mg kg(-1) wet weight and 0.20 kg(-1) wet weigh, respectively, between 2008 and 2010. This is higher than levels elsewhere in Japan (0.125 mg kg(-1) wet weight and 0.038 mg kg(-1) wet weight, respectively). The FDA (2001) and EPA (2004) suggested that a proportion of mercury accumulated in fish is derived from seawater. We reared young red sea bream (Pagrus major) over a 2-year period in Minamata Bay and Nagashima (control) to evaluate the uptake of mercury from seawater and dietary sources. Fish were fed a synthesized diet that did not contain mercury. There was no difference in mercury accumulation in the muscle of red sea bream between Minamata Bay and Nagashima. Thus, our results suggest that the majority of mercury accumulated in fish muscle is not from seawater.

Differences in lipid distribution and expression of peroxisome proliferator-activated receptor gamma and lipoprotein lipase genes in torafugu and red seabream

Lipid content is one of the major determinants of the meat quality in fish. However, the mechanisms underlying the species-specific distribution of lipid are still poorly understood. The present study was undertaken to investigate the mechanisms associated with lipid accumulation in two species of fish: torafugu (a puffer fish) and red seabream. The lipid content of liver and carcass were 67.0% and 0.8% for torafugu, respectively, and 8.8% and 7.3% for red seabream, respectively. Visceral adipose tissue was only apparent in the red seabream and accounted for 73.3% of its total lipid content. Oil red O staining confirmed this species-specific lipid distribution, and further demonstrated that the lipid in the skeletal muscle of the red seabream was mainly localized in the myosepta. We subsequently cloned cDNAs from torafugu encoding lipoprotein lipase 1 (LPL1) and LPL2, important enzymes for the uptake of lipids from blood circulation system into various tissues. The relative mRNA levels of peroxisome proliferator-activated receptor gamma (PPARγ) and the LPLs of torafugu were determined by quantitative real-time PCR together with their counterparts in red seabream previously reported. The relative mRNA levels of PPARγ and LPL1 correlated closely to the lipid distribution of both fish, being significantly higher in liver than skeletal muscle in torafugu, whereas the highest in the adipose tissue, followed by liver and skeletal muscle in red seabream. However, the relative mRNA levels of LPL2 were tenfold lower than LPL1 in both species and only correlated to lipid distribution in torafugu, suggesting that LPL2 has only a minor role in lipid accumulation. In situ hybridization revealed that the transcripts of LPL1 co-localized with lipids in the adipocytes located along the myosepta of the skeletal muscle of red seabream. These results suggest that the transcriptional regulation of PPARγ and LPL1 is responsible for the species-specific lipid distribution of torafugu and red seabream.

Purification and Characterization of a Gelatinolytic Metalloproteinase from the Skeletal Muscle of Red Sea Bream (Pagrus major)

A gelatinolytic metalloproteinase (gMP) from red sea bream ( Pagrus major ) skeletal muscle was highly purified by ammonium sulfate fractionation and column chromatographies including (diethylamino)ethyl (DEAE)-Sephacel, phenyl-Sepharose, and gelatin-Sepharose. Purified gMP revealed two bands with molecular masses of 52 and 55 kDa as estimated by sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) under reducing conditions. The 55 kDa band is quite possibly a glycosylated form of the 52 kDa band. The proteinase revealed optimal activity at 40 degrees C and pH 8.0. Metalloproteinase inhibitors including ethylenediaminetetraacetic acid (EDTA), ethylene glycol bis(2-aminoethyl ether)-N,N,N',N'-tetraacetic acid (EGTA), and 1,10-phenanthroline specifically suppressed its activity. gMP was also significantly inhibited by cysteine and dithiothreitol. Divalent metal ion Ca(2+) is essential for its gelatinolytic activity. Thus, the proteinase is regarded as a matrix metalloproteinase-like proteinase. Furthermore, gMP hydrolyzed gelatin and type-I collagen effectively even at 4 degrees C, suggesting the possibility of its involvement in the texture tenderization of fish muscle during the post-mortem stage.

Purification and characterization of a collagenolytic serine proteinase from the skeletal muscle of red sea bream (Pagrus major)

A collagenolytic serine proteinase (CSP) was purified from red sea bream (Pagrus major) skeletal muscle to homogeneity by ammonium sulfate fractionation and chromatographies including DEAE-Sephacel, Phenyl Sepharose and Hydroxyapatite. The molecular mass of CSP was approximately 85 kDa as estimated by SDS-PAGE and gel filtration. Optimum temperature and pH of CSP were 40 degrees C and 8.0, respectively. CSP was specifically inhibited by serine proteinase inhibitors, while inhibitors to other type proteinases did not show much inhibitory effects. The K(m) and k(cat) values of CSP for Boc-Leu-Lys-Arg-MCA were 3.58 microM and 0.13 s(-1) at 37 degrees C, respectively. Furthermore, CSP hydrolyzed gelatin and native type I collagen effectively though its degradation on myosin heavy chain (MHC) was not significant, suggesting its involvement in the texture tenderization of fish muscle during the post-mortem stage.

급이 및 비급이 참돔의 조직감 비교

참돔을 보다 효율적으로 이용할 목적으로 참돔의 급이 및 비급이에 따른 조직감과 같은 기호적 특성에 대하여 비교하여 살펴보았다. 비급이 참돔의 수분함량 및 조지방 함량은 각각 72.7% 및 3.7%로, 급이 참돔의 각각 70.0% 및 6.6%에 비하여, 수분함량의 경우 약 3%가 높았고, 조지방 함량의 경우 약 3%가 낮아 5% 유의수준에서 차이가 있었다. 근육의 경도는 비급이 참돔이 0.93 ㎏/㎠으로, 급이 참돔의 0.47 ㎏/㎠에 비하여 조직감이 다소 강하리라 추정되었다. 콜라겐 함량, 콜라겐의 아세트산에 대한 용해도, 산가용성 콜라겐의 열변성 온도 및 전기영동적 분자구성 등의 결과로 미루어 보아 급이 및 비급이 참돔 근육 유래 콜라겐 간에는 차이가 없었다. 이와 같은 지질함량, 콜라겐의 특성, 경도 및 관능적 조직감의 결과로 미루어 보아 비급이 참돔 및 급이 참돔간에 근육의 조직감 차이는 지질 함량에 의한 영향이라 판단되었다.

급이 및 비급이 참돔의 색, 맛 및 영양성분 비교

Division of Marine Bioscience/Institute of Marine Industry, Gyeongsang National University, Tongyeong 650-160, KoreaAbstractFor the effective use of cultured red seabream, the muscle color, taste and nutrition components between red seabreams cultured by feeding and starving were compared. The proximate composition of red seabream muscle cultured by starving (RCS) was 72.7% moisture, 21.1% protein, 3.7% lipid and 1.4% crude ash. In comparison to red seabream muscle cultured by feeding (RCF), moisture and crude lipid of RCS were each 3% higher and 3% lower. No difference was, however, found in the other proximate compositions. The Hunter color value of RCS was 37.52 for L value, -1.47 for a value, 0.71 for b value and 59.33 for ΔE value, which was slightly higher in the L value than that of red seabream muscle cultured feeding (RCF); however, no differences were found in the other Hunter color values. TCA soluble-N content of RCS was 403.8 mg/100 g, which was higher than that of RCF (314.7 mg/100 g). In taste values, the major free amino acids of both RCS and RCF were glutamic acid, alanine, lysine and histidine. Total amino acid content of RCS was 21.2 g/100 g, which was higher than that of RCF. The mineral content of RCS was slightly higher in potassium than that of RCF, while lower in magnesium. According to the result of sensory evaluation, RCS was superior in taste and texture to RCF, while similar in color and flavor.Key words: red seabream, starved red seabream, sliced raw fish, starved fish

Immunological detection of translation products of type V/XI collagen alpha1 gene and their degradation products in red sea bream muscle

: We previously cloned cDNA of type V/XI collagen α1 chain (ColVa1) gene from cultured cells derived from red sea bream embryo. We raised an antibody against the deduced C-telopeptide of ColVa1 in order to detect the translation products of this cDNA and their degradation products in red sea bream muscle. To improve its specificity, the antibody was purified from rabbit antiserum by use of an affinity column cross-linked with recombinant C-terminal peptide of ColVa1 produced by Epicurian coli. The purified antibody recognized a band corresponding to the α chain of type V/XI collagen in western blot analysis of the extract of cultured cells. The antibody also recognized two bands in acid-soluble and pepsin-solubilized collagens, indicating that the translation products of the ColVa1 gene are present in muscle and that bands correspond to α and β chains of type V/XI collagen. A band corresponding to a molecular weight of approximately 65 k was detected in the NaOH extracts of muscle, suggesting that type V/XI collagen α1 chain is restrictedly digested in red sea bream muscle.

Immunological detection of type V/XI collagen α1 gene in red seabream muscle

Immunological detection of type V/XI collagen α1 gene in red seabream muscle

Seasonal change in the level of collagen breakdown in red sea bream muscle

Seasonal change in the level of collagen breakdown in red sea bream muscle

Seasonal change in collagen content of red seabream muscle

SUMMARY: To investigate the correlation between firmness and the collagen content in fish muscle, we evaluated the seasonal change in collagen content of red seabream muscle on the basis of the content of protein-form hydroxyproline. Since a significant difference was observed among the ratios of proline (Pro) hydroxylation in female fish (P <0.05), the collagen content of each sample tested was converted from the ratio of Pro hydroxylation. The collagen content in male fish tended to increase from 0.96 mg/g muscle (March) to 1.27 mg/g (June), and then to decrease to 0.81 mg/g (July). In both male and female fish, the collagen contents tended to increase from July to September. Linear regression analysis revealed that there was a positive correlation between the muscle firmness and the collagen content in each month (P <0.05, male; r = 0.686, female; r = 0.742). The results suggest that the seasonal change in collagen content in muscle possibly contributes to that in firmness.

Effect of supplemental carnitine on body weight loss, proximate and lipid compositions and carnitine content of red sea bream (Pagrus major) during starvation

The effect of supplemental dietary carnitine on the body weight loss, lipid composition and carnitine content of dorsal muscle of red sea bream during starvation was investigated. Two experimental groups of red sea bream fingerlings were used. One group was fed a control diet (Diet 1; < 0.09 g carnitine/kg feed) for 30 days prior to starvation while the second group was fed a carnitine-supplemented diet (Diet 2; 4 g carnitine/kg feed). Then fish were deprived of feed for 30 days. During the feeding period, fish fed Diet 2 accumulated free-carnitine in their dorsal muscle. The acid-soluble acylcarnitine content remained constant, indicating a redistribution of free and esterified carnitine. Although the long-chain acylcarnitine in the dorsal muscle increased during starvation, no difference was observed in the long-chain acylcarnitine content between the carnitine and the control group. The higher concentration of carnitine in the diet prior to starvation clearly did not show any effect on body weight loss or on the proximate and fatty acid compositions of dorsal muscle nor on the fatty acid composition of the liver. Carnitine supplementation prior to starvation did not show any clear effect on lipid classes in dorsal muscle and liver or on crude lipid and water concentration in liver during starvation.

Extractability of glycolytic enzymes from fish muscle.

Extractability of glycolytic enzymes from the ordinary muscle of red sea bream. Pacific mackerel and carp was examined in a range of 0-0.3M KCl (pH 6.8-7.1). The amount of extracted proteins increased w ?? th an increase of KCl concentration up to 0.1M, irrespective of fish species. The dependency on KCl concentration of the extractability of glycolytic enzymes such as aldolase (ALD), glyceraldehyde-3-phosphate dehydrogenase (GAPDH) and glucosephosphate isomerase (GPI) was roughly comparable to that of total sarcoplasmic proteins. Sarcoplasmic proteins, as well as ALD, GAPDH and GPI, of Pacific mackerel were effectively extracted with 0.3% NaHCO3-containing 0.15% NaCl, 0.15M KCl, or a phosphate buffer (pH 7.5, I=0.05). The amounts of extracted ALD, GAPDH and GPI with 0.3% NaHCO3-containing 0.15% NaCl were 1.5-4 times with that of distilled water. On the other hand, most of phosphoglycerate kinase and enolase was extracted in the absence of KCl.

Effect of .BETA.-starch on growth, feed efficiency, and chemical components of liver, muscle, and blood of carp and red sea bream.

In order to examine whether β-corn starch(raw starch) exhibits some nutritional effect to carp Cyprinus carpio and red sea bream Chrysophrys major, the fishes were reared on the diets containing α-starch (pregelatinized starch) orβ- starch at different levels for 6 weeks. Carp fed on the β-starch diets showed high growth, feed efficiency, and protein efficiency ratio (PER) as compared with the corresponding α-starch diet groups. On the other hand, the growth, feed efficiency, and PER of red sea bream fed on the 35% starch diet were higher in the β-starch diet group than in the α-starch diet group, though a reverse tendency was observed in the case of 15 and 25% starch diets. As for the percentage absorption of protein by carp and red sea bream, there was little difference between the β-stazch diet groups and the α-starch diet groups. However, both fishes showed a significantly low absorption of β-starch in contrast with the high absorption of α-starch. Besides this, the lower glycogen contents in liver and muscle of carp, and the lower glycogen and higher protein contents in liver of red sea bream were noticed in the β-starch diet groups, From these results, it was considered that the dietary β-starch exhibits some nutritional effect on carp and red sea bream.