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Sevgili H, Kurtoğlu A, Oikawa M, Pak F, Aktaş Ö, Sivri FM, Eroldoğan OT. Dietary salt concentrations influence growth, nutrient utilization, and fatty acid profiles of turbot (Scophthalmus maximus) reared in brackish water. FISH PHYSIOLOGY AND BIOCHEMISTRY 2024:10.1007/s10695-024-01391-w. [PMID: 39126441 DOI: 10.1007/s10695-024-01391-w] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/07/2024] [Accepted: 07/23/2024] [Indexed: 08/12/2024]
Abstract
Expansion of economically viable turbot (Scophthalmus maximus) aquaculture depends on access to brackish-cold ground water sources in various parts of the world. Since brackish water sources can adversely affect the physiology and zoo technical performance of fish due to the burden of osmoregulation, dietary salt inclusion can alleviate the negative impacts of low-saline waters in several aquaculture species. This study investigated the effects of increasing dietary salt levels on the growth, feed utilization, body composition, and tissue fatty acid composition of juvenile turbot (initial live weight 120.3 ± 0.03 g/fish). Fish were fed five experimental diets supplemented with varying levels of sodium chloride (1.8-6.4%) or a control diet without salt. Each diet was tested in triplicate tanks for 9 weeks. Results showed that increasing dietary salt intake negatively impacted turbot performance, with significant reductions in weight gain, specific growth rate, and feed conversion ratio. Dry matter and ash content in the whole body and filet increased quadratically with increasing salt levels, whereas gill moisture and protein content decreased linearly. Furthermore, the nitrogen, lipid, and energy utilization efficiencies decreased with their respective intake and gain levels. Dietary salt significantly influenced the fatty acid profiles of gill, liver, and filet tissues. In the gill, monounsaturated fatty acids (16:1n-7, ΣMUFA) and n-6 PUFA (20:2n-6) increased, whereas EPA and DHA decreased. Liver ΣSFA (16:0, 18:0) increased, and n-3 PUFA (18:3n-3, 20:5n-3) decreased with increasing dietary salt. Filet saturated fatty acids (14:0, 15:0, 17:0) and n-6 PUFA (20:2n-6, 20:4n-6) increased, while n-3 PUFA (18:3n-3, EPA) decreased with dietary salt. DHA levels in filets showed a quadratic increase. Overall, this study shows that increasing dietary salt negatively impacts turbot growth, feed utilization, and tissue fatty acid composition in brackish water, highlighting the need for further studies on salinity management strategies for turbot aquaculture.
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Affiliation(s)
- Hüseyin Sevgili
- Fisheries Application and Research Center & Department of Aquaculture, Eğirdir Fisheries Faculty, Isparta University of Applied Sciences, Eastern Campus, 32260, Isparta, Turkey.
| | - Adem Kurtoğlu
- Mediterranean Fisheries Research Production and Training Institute, Beymelek Unit, Demre, Antalya, Turkey
| | - Masahiro Oikawa
- Mediterranean Fisheries Research Production and Training Institute, Beymelek Unit, Demre, Antalya, Turkey
| | - Faruk Pak
- Mediterranean Fisheries Research Production and Training Institute, Beymelek Unit, Demre, Antalya, Turkey
| | - Özgür Aktaş
- Mediterranean Fisheries Research Production and Training Institute, Beymelek Unit, Demre, Antalya, Turkey
| | - Firdevs Mert Sivri
- Department of Basic Pharmaceutical Sciences, Faculty of Pharmacy, Süleyman Demirel University, Isparta, 32200, Turkey
| | - O Tufan Eroldoğan
- Department of Aquaculture, Faculty of Fisheries, Çukurova University, 01330, Balcalı, Adana, Turkey
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Peng Z, Rehman A, Li X, Jiang X, Tian C, Wang X, Li H, Wang Z, He S, Du X. Comprehensive Evaluation and Transcriptome Analysis Reveal the Salt Tolerance Mechanism in Semi-Wild Cotton ( Gossypium purpurascens). Int J Mol Sci 2023; 24:12853. [PMID: 37629034 PMCID: PMC10454576 DOI: 10.3390/ijms241612853] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/20/2023] [Revised: 08/03/2023] [Accepted: 08/14/2023] [Indexed: 08/27/2023] Open
Abstract
Elevated salinity significantly threatens cotton growth, particularly during the germination and seedling stages. The utilization of primitive species of Gossypium hirsutum, specifically Gossypium purpurascens, has the potential to facilitate the restoration of genetic diversity that has been depleted due to selective breeding in modern cultivars. This investigation evaluated 45 G. purpurascens varieties and a salt-tolerant cotton variety based on 34 morphological, physiological, and biochemical indicators and comprehensive salt tolerance index values. This study effectively identified a total of 19 salt-tolerant and two salt-resistant varieties. Furthermore, transcriptome sequencing of a salt-tolerant genotype (Nayanmian-2; NY2) and a salt-sensitive genotype (Sanshagaopao-2; GP2) revealed 2776, 6680, 4660, and 4174 differentially expressed genes (DEGs) under 0.5, 3, 12, and 24 h of salt stress. Gene ontology enrichment analysis indicated that the DEGs exhibited significant enrichment in biological processes like metabolic (GO:0008152) and cellular (GO:0009987) processes. MAPK signaling, plant-pathogen interaction, starch and sucrose metabolism, plant hormone signaling, photosynthesis, and fatty acid metabolism were identified as key KEGG pathways involved in salinity stress. Among the DEGs, including NAC, MYB, WRKY, ERF, bHLH, and bZIP, transcription factors, receptor-like kinases, and carbohydrate-active enzymes were crucial in salinity tolerance. Weighted gene co-expression network analysis (WGCNA) unveiled associations of salt-tolerant genotypes with flavonoid metabolism, carbon metabolism, and MAPK signaling pathways. Identifying nine hub genes (MYB4, MYB105, MYB36, bZIP19, bZIP43, FRS2 SMARCAL1, BBX21, F-box) across various intervals offered insights into the transcriptional regulation mechanism of salt tolerance in G. purpurascens. This study lays the groundwork for understanding the important pathways and gene networks in response to salt stress, thereby providing a foundation for enhancing salt tolerance in upland cotton.
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Affiliation(s)
- Zhen Peng
- Zhengzhou Research Base, National Key Laboratory of Cotton Bio-Breeding and Integrated Utilization, School of Agricultural Sciences, Zhengzhou University, Zhengzhou 450001, China; (Z.P.); (A.R.); (X.L.); (X.J.); (C.T.); (X.W.); (H.L.)
- National Key Laboratory of Cotton Bio-Breeding and Integrated Utilization, Institute of Cotton Research, Chinese Academy of Agricultural Sciences, Anyang 455000, China;
- National Nanfan Research Institute (Sanya), Chinese Academy of Agricultural Sciences, Sanya 572025, China
| | - Abdul Rehman
- Zhengzhou Research Base, National Key Laboratory of Cotton Bio-Breeding and Integrated Utilization, School of Agricultural Sciences, Zhengzhou University, Zhengzhou 450001, China; (Z.P.); (A.R.); (X.L.); (X.J.); (C.T.); (X.W.); (H.L.)
- National Key Laboratory of Cotton Bio-Breeding and Integrated Utilization, Institute of Cotton Research, Chinese Academy of Agricultural Sciences, Anyang 455000, China;
| | - Xiawen Li
- Zhengzhou Research Base, National Key Laboratory of Cotton Bio-Breeding and Integrated Utilization, School of Agricultural Sciences, Zhengzhou University, Zhengzhou 450001, China; (Z.P.); (A.R.); (X.L.); (X.J.); (C.T.); (X.W.); (H.L.)
| | - Xuran Jiang
- Zhengzhou Research Base, National Key Laboratory of Cotton Bio-Breeding and Integrated Utilization, School of Agricultural Sciences, Zhengzhou University, Zhengzhou 450001, China; (Z.P.); (A.R.); (X.L.); (X.J.); (C.T.); (X.W.); (H.L.)
| | - Chunyan Tian
- Zhengzhou Research Base, National Key Laboratory of Cotton Bio-Breeding and Integrated Utilization, School of Agricultural Sciences, Zhengzhou University, Zhengzhou 450001, China; (Z.P.); (A.R.); (X.L.); (X.J.); (C.T.); (X.W.); (H.L.)
| | - Xiaoyang Wang
- Zhengzhou Research Base, National Key Laboratory of Cotton Bio-Breeding and Integrated Utilization, School of Agricultural Sciences, Zhengzhou University, Zhengzhou 450001, China; (Z.P.); (A.R.); (X.L.); (X.J.); (C.T.); (X.W.); (H.L.)
| | - Hongge Li
- Zhengzhou Research Base, National Key Laboratory of Cotton Bio-Breeding and Integrated Utilization, School of Agricultural Sciences, Zhengzhou University, Zhengzhou 450001, China; (Z.P.); (A.R.); (X.L.); (X.J.); (C.T.); (X.W.); (H.L.)
- National Key Laboratory of Cotton Bio-Breeding and Integrated Utilization, Institute of Cotton Research, Chinese Academy of Agricultural Sciences, Anyang 455000, China;
| | - Zhenzhen Wang
- National Key Laboratory of Cotton Bio-Breeding and Integrated Utilization, Institute of Cotton Research, Chinese Academy of Agricultural Sciences, Anyang 455000, China;
| | - Shoupu He
- Zhengzhou Research Base, National Key Laboratory of Cotton Bio-Breeding and Integrated Utilization, School of Agricultural Sciences, Zhengzhou University, Zhengzhou 450001, China; (Z.P.); (A.R.); (X.L.); (X.J.); (C.T.); (X.W.); (H.L.)
- National Key Laboratory of Cotton Bio-Breeding and Integrated Utilization, Institute of Cotton Research, Chinese Academy of Agricultural Sciences, Anyang 455000, China;
- National Nanfan Research Institute (Sanya), Chinese Academy of Agricultural Sciences, Sanya 572025, China
| | - Xiongming Du
- Zhengzhou Research Base, National Key Laboratory of Cotton Bio-Breeding and Integrated Utilization, School of Agricultural Sciences, Zhengzhou University, Zhengzhou 450001, China; (Z.P.); (A.R.); (X.L.); (X.J.); (C.T.); (X.W.); (H.L.)
- National Key Laboratory of Cotton Bio-Breeding and Integrated Utilization, Institute of Cotton Research, Chinese Academy of Agricultural Sciences, Anyang 455000, China;
- National Nanfan Research Institute (Sanya), Chinese Academy of Agricultural Sciences, Sanya 572025, China
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Bao Y, Shen Y, Li X, Wu Z, Jiao L, Li J, Zhou Q, Jin M. A New Insight Into the Underlying Adaptive Strategies of Euryhaline Marine Fish to Low Salinity Environment Through Cholesterol Nutrition to Regulate Physiological Responses. Front Nutr 2022; 9:855369. [PMID: 35571938 PMCID: PMC9097951 DOI: 10.3389/fnut.2022.855369] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/15/2022] [Accepted: 03/14/2022] [Indexed: 01/28/2023] Open
Abstract
Salinity is an important environmental factor that can affect the metabolism of aquatic organisms, while cholesterol can influence cellular membrane fluidity which are vital in adaption to salinity changes. Hence, a 4-week feeding trial was conducted to evaluate the effects of water salinity (normal 23 psu and low 5 psu) and three dietary cholesterol levels (CH0.16, 0.16%, CH1.0, 1.0% and CH1.6, 1.6%) on osmoregulation, cholesterol metabolism, fatty acid composition, long-chain polyunsaturated fatty acid (LC-PUFA) biosynthesis, oxidative stress (OS), and endoplasmic reticulum stress (ERS) of the euryhaline fish black seabream (Acanthopagrus schlegelii). The results indicated that in low salinity, fish fed with the CH1.0 diet improved ion reabsorption and osmoregulation by increased Na+ concentration in serum as well as expression levels of osmoregulation-related gene expression levels in gills. Both dietary cholesterol level and water salinity significantly affected most cholesterol metabolic parameters in the serum and tissues, and the results showed that low salinity promoted cholesterol synthesis but inhibited cholesterol catabolism. Besides, in low salinity, hepatic expression levels of LC-PUFA biosynthesis genes were upregulated by fed dietary cholesterol supplementation with contents of LC-PUFAs, including EPA and DHA being increased. Malondialdehyde (MDA) was significantly increased in low-salinity environment, whereas MDA content was decreased in fish fed with dietary CH1.0 by activating related antioxidant enzyme activity and gene expression levels. A similar pattern was recorded for ERS, which stimulated the expression of nuclear factor kappa B (nf-κb), triggering inflammation. Nevertheless, fish reared in low salinity and fed with dietary CH1.0 had markedly alleviated ERS and downregulated gene expression levels of pro-inflammatory cytokines. Overall, these findings demonstrate that cholesterol, as an important nutrient, plays vital roles in the process of adaptation to low salinity of A. schlegelii, and provides a new insight into underlying adaptive strategies of euryhaline marine fish reared in low salinity.
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Affiliation(s)
- Yangguang Bao
- Laboratory of Fish and Shellfish Nutrition, School of Marine Sciences, Ningbo University, Ningbo, China
- Key Laboratory of Aquaculture Biotechnology Ministry of Education, Ningbo University, Ningbo, China
| | - Yuedong Shen
- Laboratory of Fish and Shellfish Nutrition, School of Marine Sciences, Ningbo University, Ningbo, China
- Key Laboratory of Aquaculture Biotechnology Ministry of Education, Ningbo University, Ningbo, China
| | - Xuejiao Li
- Laboratory of Fish and Shellfish Nutrition, School of Marine Sciences, Ningbo University, Ningbo, China
- Key Laboratory of Aquaculture Biotechnology Ministry of Education, Ningbo University, Ningbo, China
| | - Zhaoxun Wu
- Laboratory of Fish and Shellfish Nutrition, School of Marine Sciences, Ningbo University, Ningbo, China
- Key Laboratory of Aquaculture Biotechnology Ministry of Education, Ningbo University, Ningbo, China
| | - Lefei Jiao
- Laboratory of Fish and Shellfish Nutrition, School of Marine Sciences, Ningbo University, Ningbo, China
- Key Laboratory of Aquaculture Biotechnology Ministry of Education, Ningbo University, Ningbo, China
| | - Jing Li
- Laboratory of Fish and Shellfish Nutrition, School of Marine Sciences, Ningbo University, Ningbo, China
- Key Laboratory of Aquaculture Biotechnology Ministry of Education, Ningbo University, Ningbo, China
| | - Qicun Zhou
- Laboratory of Fish and Shellfish Nutrition, School of Marine Sciences, Ningbo University, Ningbo, China
- Key Laboratory of Aquaculture Biotechnology Ministry of Education, Ningbo University, Ningbo, China
| | - Min Jin
- Laboratory of Fish and Shellfish Nutrition, School of Marine Sciences, Ningbo University, Ningbo, China
- Key Laboratory of Aquaculture Biotechnology Ministry of Education, Ningbo University, Ningbo, China
- *Correspondence: Min Jin
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Shiomi A, Nagao K, Kasai H, Hara Y, Umeda M. Changes in the physicochemical properties of fish cell membranes during cellular senescence. Biosci Biotechnol Biochem 2019; 84:583-593. [PMID: 31760866 DOI: 10.1080/09168451.2019.1695576] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/15/2023]
Abstract
Fish cell lines are widely used for the studies of developmental biology, virology, biology of aging, and nutrition physiology. However, little is known about their physicochemical properties. Here, we report the phospholipid compositions and mechanical properties of cell membranes derived from freshwater, anadromous and marine fish species. Biophysical analyses revealed that fish cell lines have highly deformable cell membranes with significantly low membrane tensions and Young's moduli compared with those of mammalian cell lines. The induction of cellular senescence by DNA demethylation using 5-Aza-2'-deoxycytidine significantly reduced the deformability of fish cell membrane, but hydrogen peroxide-induced oxidative stress did not affect the deformability. Mass spectrometry analysis of phospholipids revealed that the level of phosphatidylethanolamine molecules containing polyunsaturated fatty acids significantly increased during the 5-Aza-2'-deoxycytidine-induced cellular senescence. Fish cell lines provide a useful model system for studying the changes in the physicochemical properties of cell membranes during cellular senescence.Abbreviations: 2D-TLC: two-dimensional thin layer chromatography; 5-Aza-dC: 5-Aza-2'-deoxycytidine; DHA: docosahexaenoic acid; EPA: eicosapentaenoic acid; FBS: fetal bovine serum; PC: phosphatidylcholine; PE: phosphatidylethanolamine; PI: phosphatidylinositol; PS: phosphatidylserine; PUFA: polyunsaturated fatty acid; SA-β-gal: senescence-associated beta-galactosidase; SM: sphingomyelin.
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Affiliation(s)
- Akifumi Shiomi
- Department of Synthetic Chemistry and Biological Chemistry, Graduate School of Engineering, Kyoto University, Kyoto, Japan
| | - Kohjiro Nagao
- Department of Synthetic Chemistry and Biological Chemistry, Graduate School of Engineering, Kyoto University, Kyoto, Japan
| | - Hisae Kasai
- Laboratory of Marine Biotechnology and Microbiology, Faculty of Fisheries Sciences, Hokkaido University, Hakodate, Japan
| | - Yuji Hara
- Department of Synthetic Chemistry and Biological Chemistry, Graduate School of Engineering, Kyoto University, Kyoto, Japan
| | - Masato Umeda
- Department of Synthetic Chemistry and Biological Chemistry, Graduate School of Engineering, Kyoto University, Kyoto, Japan
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5
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Zhang Q, Wong MKS, Li Y, Li Y, Takei Y. Changes in Plasma and Tissue Long-Chain Polyunsaturated Fatty Acid (LC-PUFA) Content in the Eel Anguilla japonica After External and Internal Osmotic Stress. Zoolog Sci 2017; 34:429-437. [PMID: 28990478 DOI: 10.2108/zs170031] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
We investigated the effect of external and internal osmotic stress on the profile of long-chain polyunsaturated fatty acids (LC-PUFA) in euryhaline eels Anguilla japonica. Freshwater (FW) fish were transferred to seawater (SW) for external osmotic stress or subjected to internal stress through injection with hypertonic saline. FW eels injected with isotonic saline served as controls. Plasma osmolality, Na+ concentration, and gill Na+/K+ -ATPase activity increased, but hematocrit decreased compared with controls in eels exposed to external or internal osmotic stress. The expression of two major transporter genes for SW adaptation, the Na+ -K+ -2Cl - co-transporter 1a (NKCC1a) in the gill and NKCC2b in the intestine, was up-regulated only in SW-transferred eels, suggesting a direct impact of SW on the gill and intestine via SW ingestion. Total LC-PUFA contents and DHA (22:6 n-3) increased in the gill and liver of SW-transferred eels and in the intestine of hypertonic saline-injected eels. However, total LC-PUFA content in plasma decreased after both external and internal osmotic stimuli. In contrast, the gene expression of two key enzymes involved in the LC-PUFA biosynthesis, Δ6 fatty acid desaturase and elongase, did not change in the gill, intestine and liver of osmotically stressed eels. These results indicate that LC-PUFA is possibly involved in osmoregulation and the increased LC-PUFA contents of osmoregulatory organs might be a result of LC-PUFA transport via circulation, rather than through de novo biosynthesis.
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Affiliation(s)
- Qinghao Zhang
- 1 Marine Biology Institute & Guangdong Provincial Key Laboratory of Marine Biotechnology, Shantou University, Shantou, Guangdong 515063, China
| | - Marty K S Wong
- 2 Laboratory of Physiology, Department of Marine Bioscience, Atmosphere and Ocean Research Institute, The University of Tokyo, Chiba 277-8564, Japan
| | - Yiqi Li
- 3 School of Life Sciences, Sun Yat-sen University, Guangzhou, Guangdong 510275, China
| | - Yuanyou Li
- 1 Marine Biology Institute & Guangdong Provincial Key Laboratory of Marine Biotechnology, Shantou University, Shantou, Guangdong 515063, China.,2 Laboratory of Physiology, Department of Marine Bioscience, Atmosphere and Ocean Research Institute, The University of Tokyo, Chiba 277-8564, Japan.,4 School of Marine Sciences, South China Agricultural University, Guangzhou, Guangdong 510642, China
| | - Yoshio Takei
- 2 Laboratory of Physiology, Department of Marine Bioscience, Atmosphere and Ocean Research Institute, The University of Tokyo, Chiba 277-8564, Japan
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Maruhenda Egea FC, Toledo-Guedes K, Sanchez-Jerez P, Ibanco-Cañete R, Uglem I, Saether BS. A Metabolomic Approach To Detect Effects of Salmon Farming on Wild Saithe (Pollachius virens) Populations. JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY 2015; 63:10717-10726. [PMID: 26600204 DOI: 10.1021/acs.jafc.5b04765] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/05/2023]
Abstract
A metabolomics approach was used to analyze effects of salmon farming on wild saithe (Pollachius virens) populations. Saithe fish were captured at two salmon farms and at two control locations around the island of Hitra, Norway. Changes in diet seem to drive changes in metabolic status of fishes. The liver and muscle tissues, from the fishes captured around the farm, showed higher levels of lactate and certain amino acids (glutamine, glutamate, and alanine) and lower levels of glucose and choline than the fishes captured in the control locations, far from the farm locations. The higher levels of lactate and amino acids could be related to the facility of obtaining food around the farm and the deficit in choline to the deficit of this nutrient in the salmon feed. At each location the fish were captured with either benthic gill nets and automatic jigging machines, and this feature showed also variations in different metabolites.
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Affiliation(s)
| | - Kilian Toledo-Guedes
- Norwegian Institute of Nature Research (NINA) , Tungasletta 2, 7485 Trondheim, Norway
| | | | | | - Ingebrit Uglem
- Norwegian Institute of Nature Research (NINA) , Tungasletta 2, 7485 Trondheim, Norway
| | - Bjørn-Steinar Saether
- Nofima AS, The Norwegian Institute of Food, Fisheries and Aquaculture Research , 9291 Tromsø, Norway
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Fonseca-Madrigal J, Pineda-Delgado D, Martínez-Palacios C, Rodríguez C, Tocher DR. Effect of salinity on the biosynthesis of n-3 long-chain polyunsaturated fatty acids in silverside Chirostoma estor. FISH PHYSIOLOGY AND BIOCHEMISTRY 2012; 38:1047-1057. [PMID: 22249558 DOI: 10.1007/s10695-011-9589-6] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/12/2011] [Accepted: 12/13/2011] [Indexed: 05/31/2023]
Abstract
The genus Chirostoma (silversides) belongs to the family Atherinopsidae, which contains around 150 species, most of which are marine. However, Mexican silverside (Chirostoma estor) is one of the few representatives of freshwater atherinopsids and is only found in some lakes of the Mexican Central Plateau. However, studies have shown that C. estor has improved survival, growth, and development when cultured in water conditions with increased salinity. In addition, C. estor displays an unusual fatty acid composition for a freshwater fish with high docosahexaenoic acid (DHA)/ eicosapentaenoic acid (EPA) ratios. Freshwater and marine fish species display very different essential fatty acid metabolism and requirements, and so the present study investigated long-chain polyunsaturated fatty acid (LC-PUFA) biosynthesis to determine the capacity of C. estor for endogenous production of EPA and DHA, and the effect that salinity has on these pathways. Briefly, C. estor were maintained at three salinities (0, 5, and 15 ppt), and the metabolism of ¹⁴C-labeled 18:3n-3 was determined in isolated hepatocyte and enterocyte cells. The results showed that C. estor has the capacity for endogenous biosynthesis of LC-PUFA from 18-carbon fatty acid precursors, but that the pathway was essentially only active in saline conditions with virtually no activity in cells isolated from fish grown in freshwater. The activity of the LC-PUFA biosynthesis pathway was also higher in cells isolated from fish at 15 ppt compared with fish at 5 ppt. The activity was around fivefold higher in hepatocytes compared with enterocytes; although the majority of 18:3n-3 was converted to 18:4n-3 and 20:4n-3 in hepatocytes, the proportions of 18:3n-3 converted to EPA and DHA were higher in enterocytes. The data were consistent with the hypothesis that conversion of EPA to DHA could contribute, at least in part, to the generally high DHA/EPA ratios observed in the tissue lipids of C. estor.
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Affiliation(s)
- J Fonseca-Madrigal
- Laboratorio de Acuicultura, Instituto de Investigaciones Agropecuarias y Forestales, UMSNH, Av. San Juanito Itzícuaro S/N, Col. San Juanito Itzícuaro, C.P. 58330, Morelia, Michoacán, Mexico.
| | - D Pineda-Delgado
- Laboratorio de Acuicultura, Instituto de Investigaciones Agropecuarias y Forestales, UMSNH, Av. San Juanito Itzícuaro S/N, Col. San Juanito Itzícuaro, C.P. 58330, Morelia, Michoacán, Mexico
| | - C Martínez-Palacios
- Laboratorio de Acuicultura, Instituto de Investigaciones Agropecuarias y Forestales, UMSNH, Av. San Juanito Itzícuaro S/N, Col. San Juanito Itzícuaro, C.P. 58330, Morelia, Michoacán, Mexico
| | - C Rodríguez
- Departamento de Biología Animal (U.D.I. Fisiología Animal), Facultad de Biología, Universidad de La Laguna, La Laguna, Tenerife, Spain
| | - D R Tocher
- Institute of Aquaculture, University of Stirling, Stirling, UK
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Fatty acid composition and volatile compounds of caviar from farmed white sturgeon (Acipenser transmontanus). Anal Chim Acta 2008; 617:139-47. [PMID: 18486649 DOI: 10.1016/j.aca.2008.02.005] [Citation(s) in RCA: 37] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/19/2007] [Revised: 01/29/2008] [Accepted: 02/03/2008] [Indexed: 11/20/2022]
Abstract
The present study was conducted to characterize caviar obtained from farmed white sturgeons (Acipenser transmontanus) subjected to different dietary treatments. Twenty caviar samples from fish fed two experimental diets containing different dietary lipid sources have been analysed for chemical composition, fatty acids and flavour volatile compounds. Fatty acid make up of caviar was only minimally influenced by dietary fatty acid composition. Irrespective of dietary treatments, palmitic acid (16:0) and oleic acid (OA, 18:1 n-9) were the most abundant fatty acid followed by docosahexaenoic acid (DHA, 22:6 n-3) and eicopentaenoic (EPA, 20:5 n-3). Thirty-three volatile compounds were isolated using simultaneous distillation-extraction (SDE) and identified by GC-MS. The largest group of volatiles were represented by aldehydes with 20 compounds, representing the 60% of the total volatiles. n-Alkanals, 2-alkenals and 2,4-alkadienals are largely the main responsible for a wide range of flavours in caviar from farmed white surgeon.
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