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Carmen G. Sotelo - One of the best experts on this subject based on the ideXlab platform.
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New Strategy to Cope with Common Fishery Policy Landing Obligation: Collagen Extraction from Skins and Bones of Undersized Hake (merluccius merluccius).
Polymers, 2019Co-Authors: Maria Blanco, Carmen G. Sotelo, Ricardo I. Pérez-martínAbstract:In order to promote sustainable fishing practices within European fishing fleets and to avoid the large waste of valuable fish biomass through the practice of fish discarding, the new reform of the common fisheries policy includes the obligation of landing all species under total allowable catch (TAC) regulations. The new policy also prohibits the use of specimens under minimum conservation reference size for direct human cons38umption. In this context, it is necessary to find new uses for undersized fish, which might help to alleviate the costs associated with the landing obligation but without prompting the creation of a market. European hake (EH) (merluccius merluccius), which is one of the most important commercial fish species for the Spanish fishing industry, with a total TAC for 2018 of 37,423 t, is used for this study. Consistent with the current policy framework and taking into account the commercial importance of this species, the aim of this work is to study a new strategy for the extraction of collagen from the skin and bone fraction of merluccius merluccius undersized discards. Three collagen fractions are successfully isolated for the first time from the skin of M. merluccius skin and bone discarded raw material: acid-soluble collagen (ASC) fraction 1 and pepsin-soluble collagen (PSC) fraction 2 from the skin and ASC fraction 3 from bones. The total collagen yield of the process is 13.55 ± 3.18% in a dry basis (g collagen/100 g of skin and bone fraction (SBF)) and 47.80 ± 9.83% (g collagen/100 g of collagen determined by the hydroxyproline content in SBF). The three fractions are further characterized by using different physical and chemical analysis techniques, with the conclusion drawn that the triple helix structure is preserved in the three fractions, although ASC fractions (F1 and F3) present more or stronger hydrogen bonds than the PSC fraction (F2). With the process herein presented, deboned and skinned hake specimens could represent an interesting source of high quality type I collagen, which could be useful as a raw material for the biomedical, cosmetic, and nutraceutical industries.
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Comparison of real-time PCR methods for quantification of European hake (merluccius merluccius) in processed food samples
Food chemistry, 2018Co-Authors: Antonio Higinio Sánchez, Javier Quinteiro, Ricardo I. Pérez-martín, José Antonio Vázquez, Carmen G. SoteloAbstract:Abstract The quantification of species in commercial products is limited by analytical shortcomings, as most of them provide semiquantitative results. An exception is real-time PCR, which can provide quantitative results using hybridization probes. In the present work, this technique has been applied to the absolute, absolute-relative and relative quantification of the most valued hake species in European markets, merluccius merluccius (European Hake). The best quantification results for this species in binary mixtures with non-target species (merluccius capensis) and using a species-specific real-time PCR MMER_VIC system was achieved using a relative quantification approach (MLL as reference system). Absolute quantification using the MLL nuclear system has been demonstrated as appropriate for the quantification of the merluccius genus in food model samples. This study reveals the impact of different reference systems (MLL and HAKE) in the absolute-relative and relative quantification approaches, showing that the nuclear MLL system performed better than the mitochondrial HAKE system.
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Modeling real-time PCR kinetics: Richards reparametrized equation for quantitative estimation of European hake (merluccius merluccius).
Journal of agricultural and food chemistry, 2013Co-Authors: Ana Cristina Sánchez, Javier Quinteiro, José Antonio Vázquez, Carmen G. SoteloAbstract:Real-time PCR is the most sensitive method for detection and precise quantification of specific DNA sequences, but it is not usually applied as a quantitative method in seafood. In general, benchmark techniques, mainly cycle threshold (Ct), are the routine method for quantitative estimations, but they are not the most precise approaches for a standard assay. In the present work, amplification data from European hake (merluccius merluccius) DNA samples were accurately modeled by three sigmoid reparametrized equations, where the lag phase parameter (λc) from the Richards equation with four parameters was demonstrated to be the perfect substitute for Ct for PCR quantification. The concentrations of primers and probes were subsequently optimized by means of that selected kinetic parameter. Finally, the linear correlation among DNA concentration and λc was also confirmed.
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Identification of European Hake species (merluccius merluccius) using real-time PCR.
Journal of agricultural and food chemistry, 2009Co-Authors: Antonio Higinio Sánchez, Javier Quinteiro, Manuel Rey-méndez, Ricardo I. Pérez-martín, Carmen G. SoteloAbstract:A rapid and precise method for identifying European hake (merluccius merluccius) based on TaqMan technology is presented. The method can be applied to fresh, frozen, and processed fish products to detect the fraudulent or unintentional mislabeling of this species. Specific primers and a minor groove binding (MGB) TaqMan probe were designed for this purpose based on partial sequences of the mitochondrial DNA control region. Combinations of primers and probe concentrations that gave the lowest Ct value and the highest final fluorescence value were selected to carry out efficiency, specificity, and cross-reactivity assays. The method was successfully tested on 31 commercial hake samples. A Ct value of about 16 was obtained when merluccius merluccius was present; however, the fluorescence signal was not detected most of the time (Ct value 40) or presented significantly higher Ct values (38.2 ± 0.96) for the nonhake species.
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Partial purification and biochemical characterization of TMAOase from kidney of European hake (merluccius merluccius)
European Food Research and Technology, 2004Co-Authors: Mar Rey-mansilla, Carmen G. Sotelo, Roberto Munilla MoránAbstract:The trimethylamine N-oxide aldolase (TMAOase) activity from kidney of European hake (merluccius merluccius) was characterized by using chromatographic and electrophoretic techniques. Soluble TMAOase was obtained using a differential centrifugation protocol with CHAPS and NaCl buffer. Two TMAOase fractions were isolated by ion exchange chromatography using a FPLC system. For this purpose the weak anion exchanger ANX Sepharose 4 Fast Flow (high sub), suited for high molecular mass proteins, was employed. After anion exchange chromatography, fractions were separated by native electrophoresis. One of the fractions eluted at 0.45 M sodium chloride concentration, and had a charge/mass ratio in electrophoresis similar to bovine serum albumin, with a molecular weight of approximately 100 kDa. The second fraction eluted at 0.7 M sodium chloride concentration, and presented a very low electrophoretic mobility due to either a low charge/mass ratio or due to the presence of protein aggregates of different sizes of between 440 and 2,000 kDa. Proteins present in both TMAOase fractions showed acid isoelectric points of between 4.55 and 5.85.
Ricardo I. Pérez-martín - One of the best experts on this subject based on the ideXlab platform.
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New Strategy to Cope with Common Fishery Policy Landing Obligation: Collagen Extraction from Skins and Bones of Undersized Hake (merluccius merluccius).
Polymers, 2019Co-Authors: Maria Blanco, Carmen G. Sotelo, Ricardo I. Pérez-martínAbstract:In order to promote sustainable fishing practices within European fishing fleets and to avoid the large waste of valuable fish biomass through the practice of fish discarding, the new reform of the common fisheries policy includes the obligation of landing all species under total allowable catch (TAC) regulations. The new policy also prohibits the use of specimens under minimum conservation reference size for direct human cons38umption. In this context, it is necessary to find new uses for undersized fish, which might help to alleviate the costs associated with the landing obligation but without prompting the creation of a market. European hake (EH) (merluccius merluccius), which is one of the most important commercial fish species for the Spanish fishing industry, with a total TAC for 2018 of 37,423 t, is used for this study. Consistent with the current policy framework and taking into account the commercial importance of this species, the aim of this work is to study a new strategy for the extraction of collagen from the skin and bone fraction of merluccius merluccius undersized discards. Three collagen fractions are successfully isolated for the first time from the skin of M. merluccius skin and bone discarded raw material: acid-soluble collagen (ASC) fraction 1 and pepsin-soluble collagen (PSC) fraction 2 from the skin and ASC fraction 3 from bones. The total collagen yield of the process is 13.55 ± 3.18% in a dry basis (g collagen/100 g of skin and bone fraction (SBF)) and 47.80 ± 9.83% (g collagen/100 g of collagen determined by the hydroxyproline content in SBF). The three fractions are further characterized by using different physical and chemical analysis techniques, with the conclusion drawn that the triple helix structure is preserved in the three fractions, although ASC fractions (F1 and F3) present more or stronger hydrogen bonds than the PSC fraction (F2). With the process herein presented, deboned and skinned hake specimens could represent an interesting source of high quality type I collagen, which could be useful as a raw material for the biomedical, cosmetic, and nutraceutical industries.
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Comparison of real-time PCR methods for quantification of European hake (merluccius merluccius) in processed food samples
Food chemistry, 2018Co-Authors: Antonio Higinio Sánchez, Javier Quinteiro, Ricardo I. Pérez-martín, José Antonio Vázquez, Carmen G. SoteloAbstract:Abstract The quantification of species in commercial products is limited by analytical shortcomings, as most of them provide semiquantitative results. An exception is real-time PCR, which can provide quantitative results using hybridization probes. In the present work, this technique has been applied to the absolute, absolute-relative and relative quantification of the most valued hake species in European markets, merluccius merluccius (European Hake). The best quantification results for this species in binary mixtures with non-target species (merluccius capensis) and using a species-specific real-time PCR MMER_VIC system was achieved using a relative quantification approach (MLL as reference system). Absolute quantification using the MLL nuclear system has been demonstrated as appropriate for the quantification of the merluccius genus in food model samples. This study reveals the impact of different reference systems (MLL and HAKE) in the absolute-relative and relative quantification approaches, showing that the nuclear MLL system performed better than the mitochondrial HAKE system.
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Identification of European Hake species (merluccius merluccius) using real-time PCR.
Journal of agricultural and food chemistry, 2009Co-Authors: Antonio Higinio Sánchez, Javier Quinteiro, Manuel Rey-méndez, Ricardo I. Pérez-martín, Carmen G. SoteloAbstract:A rapid and precise method for identifying European hake (merluccius merluccius) based on TaqMan technology is presented. The method can be applied to fresh, frozen, and processed fish products to detect the fraudulent or unintentional mislabeling of this species. Specific primers and a minor groove binding (MGB) TaqMan probe were designed for this purpose based on partial sequences of the mitochondrial DNA control region. Combinations of primers and probe concentrations that gave the lowest Ct value and the highest final fluorescence value were selected to carry out efficiency, specificity, and cross-reactivity assays. The method was successfully tested on 31 commercial hake samples. A Ct value of about 16 was obtained when merluccius merluccius was present; however, the fluorescence signal was not detected most of the time (Ct value 40) or presented significantly higher Ct values (38.2 ± 0.96) for the nonhake species.
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Trimethylamine oxide and derived compounds' changes during frozen storage of hake (merluccius merluccius)
Food Chemistry, 1995Co-Authors: Carmen G. Sotelo, José Manuel Gallardo, Carmen Piñeiro, Ricardo I. Pérez-martínAbstract:Changes in total volatile bases (TVB), dimethylamine (DMA), formaldehyde (FA), trimethylamine (TMA) and trimethylamine oxide (TMAO) of whole hake (merluccius merluccius L.) were evaluated at different temperatures of storage: −5, −12 and −20 °C. Significant changes in TVB, DMA, TMA, TMAO nitrogen and FA were observed at −5 °C. Only TMAO changed significantly at −12 °C and −20 °C. TMAO decrease was not, therefore, followed by DMA and/or TMA production at those temperatures.
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Protein denaturation in frozen stored hake (merluccius merluccius L.) muscle: The role of formaldehyde
Food Chemistry, 1994Co-Authors: Carmen G. Sotelo, Santiago P Aubourg, Ricardo I. Pérez-martín, José Manuel GallardoAbstract:Protein solubility of whole and minced muscle of hake (merluccius merluccius L.) was evaluated at different temperatures of storage: −5°, −12° and −20°C. Proteins soluble in 1% NaCl did not show any change at any of the temperatures of storage, while the 5% NaCl-soluble proteins decreased significantly when whole hake was stored at −5° and −12°C (p < 0·01). A correlation was found between the decrease of solubility and the production of formaldehyde at −5° and −12°C (p < 0·001 and p < 0·01, respectively). Bound formaldehyde (formaldehyde not extractable) increased with storage time at −5° (p < 0.001). The addition of formaldehyde to the minced muscle brought about a decrease in both the 1% and the 5% NaCl-soluble proteins. The decrease was dependent upon the temperature, the amount of formaldehyde added and the time of storage. The role of formaldehyde in the denaturation of sarcoplasmic proteins was confirmed by measuring trimethylamino oxide demethylase activity during the experiment.
Hélène De Pontual - One of the best experts on this subject based on the ideXlab platform.
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Diel vertical migration of European hake merluccius merluccius and associated temperature histories: insights from a pilot data-storage tagging (DST) experiment
Journal of Fish Biology, 2012Co-Authors: Hélène De Pontual, M. Bertignac, A. Jolivet, Ronan FabletAbstract:A pioneering experiment of archival tagging of European hake merluccius merluccius provided evidence of a diel vertical migration pattern which was analysed using an automatic method, developed and validated through time-frequency analyses. Frequent vertical movements across the thermocline were observed and fish experienced rapid temperature changes >7° C. These tagging-recapture data also suggested a homing behaviour to feeding grounds.
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growth of european hake merluccius merluccius in the gulf of lions based on conventional tagging
Ices Journal of Marine Science, 2010Co-Authors: Capucine Mellonduval, Hélène De Pontual, Luisa Metral, Loic QuemenerAbstract:Mellon-Duval, C., de Pontual, H., Metral, L., and Quemener, L. 2010. Growth of European hake (merluccius merluccius) in the Gulf of Lions based on conventional tagging. - ICES Journal of Marine Science, 67: 62-70.Growth of European hake was estimated from the results of a conventional tagging study in the Gulf of Lions, the first tagging experiment to have been undertaken on the species in Mediterranean waters. In all, 4277 hake 15-40 cm long were tagged and released on the inshore fishing grounds during spring 2006. The overall recapture rate was 6.5% and times-at-liberty ranged from 1 to 717 d. Growth rate in hake varied with size and sex. The estimated growth parameter (von Bertalanffy k) was estimated as double previously published values based on size frequency distribution in the area. Compared with recent growth parameters derived from the tagging experiments in the Bay of Biscay, k was estimated to be slightly lower in the Gulf of Lions. With this faster growth, hake would mature earlier than previously thought: at age 2 for both sexes, instead of at age 3 or 4 as currently accepted for the Mediterranean. Growth rate by sex decreased to a similar level once fish had attained sexual maturity.
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Growth of European hake (merluccius merluccius) in the Gulf of Lions based on conventional tagging
ICES Journal of Marine Science, 2009Co-Authors: Capucine Mellon-duval, Hélène De Pontual, Luisa Metral, Loic QuemenerAbstract:Abstract Mellon-Duval, C., de Pontual, H., Métral, L., and Quemener, L. 2010. Growth of European hake (merluccius merluccius) in the Gulf of Lions based on conventional tagging. – ICES Journal of Marine Science, 67: 62–70. Growth of European hake was estimated from the results of a conventional tagging study in the Gulf of Lions, the first tagging experiment to have been undertaken on the species in Mediterranean waters. In all, 4277 hake 15–40 cm long were tagged and released on the inshore fishing grounds during spring 2006. The overall recapture rate was 6.5% and times-at-liberty ranged from 1 to 717 d. Growth rate in hake varied with size and sex. The estimated growth parameter (von Bertalanffy k) was estimated as double previously published values based on size frequency distribution in the area. Compared with recent growth parameters derived from the tagging experiments in the Bay of Biscay, k was estimated to be slightly lower in the Gulf of Lions. With this faster growth, hake would mature earlier than previously thought: at age 2 for both sexes, instead of at age 3 or 4 as currently accepted for the Mediterranean. Growth rate by sex decreased to a similar level once fish had attained sexual maturity.
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Tag and recapture of European hake (merluccius merluccius L.) off the Northwest Iberian Peninsula: First results support fast growth hypothesis
Fisheries Research, 2007Co-Authors: Carmen Piñeiro, Hélène De Pontual, Javier Rey, Raquel GoñiAbstract:In the first tagging experiment of European hake (merluccius merluccius L.) conducted off the NW Iberian Peninsula to study hake growth in the wild we released 527 live tagged individuals. The survival rate after capture and tagging was 58%. Mortality during capture was positively correlated with depth of capture and negatively correlated with hake size. Fifteen months after tagging, seven individuals (1.3%) had been recaptured with times at liberty ranging from 29 to 466 days. We provide the first direct measurements of growth rates of Southern stock European hake in the wild and compare them with rates obtained from tagging experiments in other regions and with rates derived from conventional otolith age reading. The mean somatic growth rate of all recaptured hake was 0.032 ± 0.016 cm day−1 (sexes combined), while the mean growth rate of the two hake with over 340 days at liberty was 0.052 ± 0.003 cm day−1 (sexes unknown). These results indicate that conventional otolith age reading methods overestimate age and underestimate growth.
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A pilot tagging experiment on European hake (merluccius merluccius): methodology and preliminary results
ICES Journal of Marine Science, 2003Co-Authors: Hélène De Pontual, M. Bertignac, André Battaglia, Gerard Bavouzet, Philippe Moguedet, Anne-laure GroisonAbstract:Abstract European hake (merluccius merluccius) were caught alive in the northern Bay of Biscay in June/July 2002, using a codend specially designed to avoid crushing fish and also to retain water while hauling the trawl. In all, 1307 fish were tagged with anchor T-bar tags, injected with tetracycline, then released. The length range of the tagged and marked fish varied from 13 to 58 cm, and the modal size was 28 cm, at which length they were assumed to be 2–3 years old. A mean survival rate of 68.2% was estimated. Mortality was mainly caused by stress of capture and physical damage, and depended on the size of the catch and the depth of trawling. By the end of March 2003, 32 fish and three tags had been returned to the laboratory (a 2.7% return rate), the recapture data indicating that the probability of survival after release does not depend on catch depth or depth at location of release. For combined sexes, the somatic growth rate was estimated at 0.033 ± 0.019 cm day−1 (n=15). Males and females did not differ significantly in somatic growth rate, which were, respectively, 0.028±0.018 (n=6) and 0.033 ± 0.012 cm day−1 (n=6). This pilot experiment represents the first recorded mass tagging of European hake, which is known to be a very fragile species. The preliminary results indicate that it would be possible to carry out a large-scale tagging experiment of the European stocks in order to improve assessment and subsequent management decisions.
Mercedes Careche - One of the best experts on this subject based on the ideXlab platform.
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Monitoring the Time and Temperature History of Frozen Hake (merluccius merluccius, L.) Muscle by FTIR Spectroscopy of the Lipid Fraction
Food and Bioprocess Technology, 2015Co-Authors: Mercedes Careche, Pedro Carmona, Isabel Sánchez-alonsoAbstract:The objective was to model the time and temperature changes of the lipid fraction of hake muscle by mid-infrared spectroscopy. Fillets of a total of 90 hake ( merluccius merluccius , L.), stored at −10, −20, −30 or −80 °C for up to 150 weeks, were used and lipids analysed by attenuated total reflectance (ATR) Fourier transform infrared spectroscopy (FTIR). Three spectral regions corresponding to ν(C-H) vibrations (3,100–2,750 cm^−1), ν(C=O) vibrations from ester and carboxylic groups (1,800–1,670 cm^−1) and ν_ as (PO_2 ^−) phospholipid vibrations (1,330–1,127 cm^−1) were studied separately. Principal component scores were used as the response variables for the kinetic modelling. Three models were obtained, each per region, and the best one resulted from the region corresponding to the phosphorous moiety of the phospholipids with R ^2 = 0.93. They kept a close relationship with other reported quality parameter such as Kramer shear resistance which suggests their potential for the estimation of frozen storage time and temperature in fishery products.
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Estimation of freezing storage time and quality changes in hake (merluccius merluccius, L.) by low field NMR.
Food chemistry, 2012Co-Authors: Isabel Sánchez-alonso, Iciar Martinez, Javier Sánchez-valencia, Mercedes CarecheAbstract:The potential of low field NMR (LF NMR) as a fast monitoring technique to estimate the quality of hake (merluccius merluccius) frozen stored at -10°C for up to 6months was evaluated. LF NMR clearly detected three populations of water: water strongly bound to macromolecules (T(2b)), trapped water (T(21)) and free water (T(22)). As storage time increased, and concomitant with an increase in the T(22) and a decrease in the T(21) water populations, the water holding capacity (WHC) and apparent viscosity values decreased and the shear strength increased, reflecting the characteristic loss of juiciness and tougher texture developed by hake during frozen storage. Two mathematical models were constructed: a simple regression using the biexponential analysis of the relaxation times (T(21), T(22)) and amplitudes (A(21), A(22)) and a partial least square regression (PLS) of CONTIN analysis. Both models seemed suitable to estimate the quality of the product.
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Structural changes of hake (merluccius merluccius L.) fillets: effects of freezing and frozen storage.
Journal of agricultural and food chemistry, 1999Co-Authors: Mercedes Careche, Ana M. Herrero, Arantxa Rodriguez-casado, M. L. Del. Mazo, Pedro CarmonaAbstract:Structural changes in hake (merluccius merluccius L.) fillets as affected by freezing method and frozen storage temperature have been studied through Raman spectroscopy and related to changes in texture and functionality. Changes in protein secondary structure were observed due to storage temperature, accompanied by changes in apparent viscosity and shear resistance. Samples at −10 °C showed greater structural alteration than at −30 °C in terms of increase of β-sheets at the expense of α-helices. An increase of unordered protein structure was found only in samples stored at −10 °C. Exposure of buried tryptophan residues was observed at both storage temperatures. The decrease of the δCH2 band upon storage suggested an increase of hydrophobic interactions of aliphatic residues. Except for liquid air frozen fillets, all samples showed a decrease of the νO−H/νC−H band ratio compared to the fresh ones, this decrease being higher the harsher the conditions. Keywords: Freezing; frozen storage; Raman spectroscopy...
Francisco Soler - One of the best experts on this subject based on the ideXlab platform.
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Comparative study of esterase activities in different tissues of marine fish species Trachurus trachurus, merluccius merluccius and Trisopterus luscus.
The Science of the total environment, 2019Co-Authors: Salomé Martínez-morcillo, Marcos Pérez-lópez, María Prado Míguez, Y. Valcárcel, Francisco SolerAbstract:Abstract Pesticides are one of the most frequently anthropogenic xenobiotics detected in water. Among these, the organophosphorus pesticides (OPs) are very widely used in agriculture due to their broad spectrum of activity and their low price, but they also have high potent effects as neurotoxic compounds in non-target organisms. The aim of this study was to evaluate biomarkers acetylcholinesterase (AChE), butyrylcholinesterase (BChE), propionylcholinesterase (PChE) and carboxylesterase (CbE) in the representative Atlantic fish species Trachurus trachurus, merluccius merluccius and Trisopterus luscus from “Rias Gallegas”, a traditional Spanish fishing area. These esterase activities were evaluated in the brain, muscle and liver to determine the most adequate tissue to measure such enzymatic activities. The sensitivity of AChE and CbE activities from different tissues the widely used organophosphorus insecticide chlorpyrifos (CP), and its toxic metabolite (CP-oxon) was also tested. AChE activity was predominant in all tissues of the analysed species (particularly in brain constituting from 78.33%, 89.83% and 88.43% of total ChEs in Trachurus trachurus, merluccius merluccius and Trisopterus luscus, respectively). Under in vitro exposure, esterases were shown to be highly sensitive to CP and especially to CP-oxon. Moreover, a similar effect observed on AChE and CbE activities could suggest that CbE activity might contribute efficiently against the toxic effects of CP, especially in muscle and the liver. The presence of BChE, PChE and upper CbE activities in muscle and the liver and their OP-sensibilities can be used to study their function in the pesticide biochemical detoxification pathways with a prominent role as a safeguarding mechanism against pesticide toxicity.