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Soottawat Benjakul - One of the best experts on this subject based on the ideXlab platform.

  • protein hydrolysates from pacific white shrimp Cephalothorax manufactured with different processes compositions characteristics and antioxidative activity
    Waste and Biomass Valorization, 2020
    Co-Authors: Sittichoke Sinthusamran, Soottawat Benjakul, Kongkarn Kijroongrojana, Thummanoon Prodpran, Hideki Kishimura
    Abstract:

    Hydrolysates from Pacific white shrimp (Litopenaeus vannamei) Cephalothorax were prepared using various hydrolysis processes, and their chemical composition, characteristics as well as antioxidative activity were studied. Those processes consisted of autolysis (AU), hydrolysis using Alcalase at 0.5% (0.5A) or 1.0% (1.0A) and autolysis, followed by Alcalase hydrolysis at 0.5 and 1.0% (AU + 0.5A and AU + 1.0A). All the hydrolysate samples had higher protein contents (86.04–89.24%) and lower amounts of ash (7.46–11.26%) and lipids (0.43–0.64%), compared to those of Cephalothorax (P < 0.05). The highest yield (54.04%) and protein recovery (84.15%) were observed in the AU + 1.0A sample, which had the maximum degree of hydrolysis (DH) (44.93%) (P < 0.05). All the hydrolysates had glutamic acid/glutamine (115.80–121.69 mg/g dry sample), aspartic acid/asparagine (84.04–90.28 mg/g dry sample), arginine (63.27–68.62 mg/g dry sample) and leucine (58.67–68.07 mg/g dry sample) as the dominant amino acids. Based on gel filtration chromatography, the hydrolysates with higher DH showed higher proportions of smaller peptides (< 1355 Da). When the antioxidant activities of the hydrolysates were determined, the AU + 1.0A sample had the highest ferrous ion chelating activity, ABTS radical scavenging activity and ORAC value, compared to the others (P < 0.05). However, the highest ferric reducing antioxidant activity and DPPH radical scavenging activity were obtained for the 1.0A and AU samples, respectively (P < 0.05). Furthermore, the AU + 1.0A sample showed higher inhibitory activity against DNA damage induced by peroxyl radicals than the 1.0A and AU samples. Therefore, different hydrolysis processes directly affected the protein recovery, chemical composition and antioxidant activities of the hydrolysates from shrimp Cephalothorax.

  • impact of pretreatment and atmosphere on quality of lipids extracted from Cephalothorax of pacific white shrimp by ultrasonic assisted process
    Food Chemistry, 2020
    Co-Authors: Saqib Gulzar, Soottawat Benjakul
    Abstract:

    Impacts of different pretreatment conditions and atmosphere on yield and oxidative stability of lipids from Pacific white shrimp (Litopenaeus vannamei) Cephalothorax using ultrasonic assisted extraction (UAE) process were studied. Cephalothorax was subjected to vacuum-microwave (VM) heating prior to UAE using a mixture of isopropanol/n-hexane (1:1) as solvent. Nitrogen gas was flushed at two flow rates; low (2.15 l/min) and high (4.35 l/min) into the system during ultrasonication. Vacuum-microwave heating resulted in the increase of lipid yield and highest yield was observed in the samples extracted by a combination of VM and UAE. Tannic acid (TA) was incorporated into Cephalothorax at three different levels (0.05, 0.1 and 0.2%) in combination with VM, followed by nitrogen flushing. Nitrogen flushing during ultrasonication process resulted in the increased oxidative stability of lipids as confirmed by low PV, TBARS and FFA. Furthermore, astaxanthin content in the lipid was found to be increased by aforementioned treatments.

  • effect of pre treatments on yield and properties of lipid extracted from Cephalothorax of pacific white shrimp litopenaeus vannamei by ultrasonic assisted process
    Lwt - Food Science and Technology, 2019
    Co-Authors: Saqib Gulzar, Soottawat Benjakul
    Abstract:

    Abstract Impacts of different pre-treatments of Cephalothorax from Pacific white shrimp before ultrasound assisted extraction (UAE) on yield and characteristics of lipids were studied. Autolysis at 50 °C for 3 h in the absence and presence of 0.1% tannic acid (TA), a lipase inhibitor, was implemented. Pre-heating of Cephalothorax containing 0.1% TA at 95 °C for different times (15–45 min) was also carried out. When UAE was used to extract the lipids at the ultrasonic amplitude of 80% for 25 min in continuous mode, samples with pre-heating rendered the highest lipid yield (13.3g-14.1 g/100 g sample). Pre-heating along with TA addition resulted in suppression of lipid oxidation as evidenced by decrease in peroxide value (PV) and thiobarbituric acid reactive substances (TBARS). Free fatty acid (FFA) content was also found to be lower, whereas the control (without pre-treatment) had higher FFA. Fourier transform infrared (FTIR) spectra confirmed lower oxidation in lipid from pre-heated samples added with TA. Lipid contained astaxanthin, astaxanthin monoester, astaxanthin diester, canthaxanthin and β-carotene. Overall, the combination of pre-heating and addition of TA was a promising means to increase the yield and maintain the quality of lipid from Cephalothorax using UAE.

  • yield and chemical composition of lipids extracted from solid residues of protein hydrolysis of pacific white shrimp Cephalothorax using ultrasound assisted extraction
    Food bioscience, 2018
    Co-Authors: Sittichoke Sinthusamran, Soottawat Benjakul, Kongkarn Kijroongrojana, Thummanoon Prodpran, Tri Winarni Agustini
    Abstract:

    Abstract The yield of lipids extracted from the lipid-containing solid residue (LSR) obtained from the protein hydrolysis of shrimp Cephalothorax using ultrasonic-assisted extraction (UAE), and their chemical compositions were determined. When UAE with different amplitudes (60%–100%) was used, the highest lipid yield (10–11 g/100 g) and carotenoids (8.6–8.8 mg/g lipid) were obtained at 80% amplitude (P

  • lipids from Cephalothorax and hepatopancreas of pacific white shrimp litopenaeus vannamei compositions and deterioration as affected by iced storage
    Food Chemistry, 2012
    Co-Authors: Sirima Takeungwongtrakul, Soottawat Benjakul, Aran Hkittikun
    Abstract:

    Lipids from Cephalothorax and hepatopancreas of Pacific white shrimp (Litopenaeus vannamei) stored in ice for up to 6 days were extracted and characterised. The extraction yields of lipids from hepatopancreas (10.65-12.64%) were higher than those from Cephalothorax (2.59-2.88%). However, no changes in the extraction yield were observed during the storage (p>0.05). The carotenoid contents of lipids from Cephalothorax and hepatopancreas slightly increased within the first 2 and 4 days of iced storage (p<0.05), respectively, but decreased thereafter (p<0.05). With increasing storage time, a progressive formation of hydroperoxide was found as evidenced by the increase in the absorbance band at 3600-3200 cm(-1) in Fourier transform infrared (FTIR) spectra, and increased peroxide values (PVs) (p<0.05). The increases in thiobarbituric acid reactive substances (TBARS), p-anisidine value (AnV) and free fatty acid (FFA) content of lipids were noticeable when iced storage time increased (p<0.05). Those changes indicated that lipid oxidation and hydrolysis occurred in both samples. Phospholipids (PL) were the major components in lipids from Cephalothorax (82.51% of total lipids). Nevertheless, lipids from hepatopancreas contained triglyceride (TG) and PL as the dominant components (45.35% and 38.03% of total lipids, respectively). A decrease in the TG content with a concomitant increase in free fatty acid was observed at the end of storage (day 6) (p<0.05). Decreases in unsaturated fatty acids, especially eicosapentaenoic acid (EPA; C20:5(n-3)) and docosahexaenoic acid (DHA; C22:6(n-3)) were noticeable at day 6 of storage (p<0.05). Thus, the extended storage time resulted in the enhanced deterioration of extracted lipids.

M C Gomezguillen - One of the best experts on this subject based on the ideXlab platform.

  • bioactive and technological functionality of a lipid extract from shrimp l vannamei Cephalothorax
    Lwt - Food Science and Technology, 2018
    Co-Authors: M C Gomezguillen, P Montero, M E Lopezcaballero, G C Baccan, Joaquin Gomezestaca
    Abstract:

    Abstract Lipid extract from shrimp Cephalothorax (LES) is a potential functional food ingredient because of its astaxanthin, α-tocopherol, and polyunsaturated fatty acid contents. This work aims at evaluating its bioactive (anti-inflammatory and antioxidant) and technological (potential for aqueous food applications) functionalities. LES was encapsulated by spray-drying, yielding a powder that was readily soluble in water. The resulting solution presented an attractive reddish colour, contrary to non-encapsulated LES. Encapsulated LES exerted anti-inflammatory activity at concentrations ≥100 μg/mL, as well as lipophilic and hydrophilic antioxidant activity. In contrast, non-encapsulated LES did not show any of these bioactivities when dissolved in water. Irrespective of processing temperature (20 °C/100 °C) or refrigerated storage time (up to 6 days at 5 °C ± 1 °C), the colour, astaxanthin content, and fatty acid composition of the encapsulated LES were relatively stable. Gelatin gels and films containing the emulsified or encapsulated LES had a homogeneous reddish colour, as well as minor physicochemical modifications (viscoelastic properties, gel strength, film water solubility, and water vapor permeability). Furthermore, the encapsulation process increased the bioaccessibility of astaxanthin to 100%, in comparison with non-emulsified LES-added samples. In conclusion, spray-dried encapsulated LES is a promising functional food ingredient, especially for aqueous applications.

  • the effect of high pressure treatment on functional components of shrimp litopenaeus vannamei Cephalothorax
    Innovative Food Science and Emerging Technologies, 2016
    Co-Authors: Joaquin Gomezestaca, P Montero, F Fernandezmartin, Marta Calvo, M C Gomezguillen
    Abstract:

    Abstract High-pressure (HP) technology has been applied to extend the shelf life of shrimps by inhibiting enzymes with PPO activity or microorganisms. However, there is very little information on its effect on relevant compounds from a nutritional or functional point of view, such as fatty acids, α-tocopherol, astaxanthin, and hemocyanin, which constitutes the main objective of the present work. Shrimp Cephalothoraxes were HP processed at 200, 400, or 600 MPa/18 °C/15 min or three consecutive 5 min cycles. It was found that hemocyanin was partially denatured at pressures up to 400 MPa, resulting in lower PPO activity, and it was totally denatured at 600 MPa, although 20% residual PPO activity remained. Astaxanthin, α-tocopherol, and total antioxidant activity were stable whichever HP treatment was applied, whereas 600 MPa caused a slight reduction of eicosapentaenoic acid (C20:5n3, EPA) and docosahexaenoic acid (C22:6n3, DHA). Despite this reduction, the ω -6/ ω -3 fatty acids ratio was very low (1). Industrial relevance Shrimps are high-value fishery products with a very short shelf life under refrigeration, mainly because of microbial growth and development of melanosis. Thermal treatment is effective for extending shelf life, but it affects the nutritional quality of shrimps through degradation of bioactives such as polyunsaturated fatty acids, tocopherols, or astaxanthin, which are mainly located in the Cephalothorax. High pressure is a non-thermal processing technology that has been proved to extend shrimp shelf life, but very little information can be found on its effect on the above-mentioned compounds as well as on the melanosis-inducing hemocyanin. Such basic knowledge is very important for industrial application of high-pressure technology to extend the shelf life of shrimps.

  • characterization of phenoloxidase activity of carapace and viscera from Cephalothorax of norway lobster nephrops norvegicus
    Lwt - Food Science and Technology, 2010
    Co-Authors: B Gimenez, Oscar Martinezalvarez, P Montero, M C Gomezguillen
    Abstract:

    Abstract The characterization of phenoloxidase activity was performed in both carapace and viscera extracts of Norway lobster. Phenoloxidase activity rose with increasing temperature up to 60 °C. The carapace enzymatic extract showed the highest themostability, retaining about 80% of maximum activity at 45 °C and 40% at 65 °C. On the other hand, both enzymatic extracts showed a single peak activity at neutral-slightly alkaline pH and were quite resistant to inactivation at alkaline pH (pH > 8), but phenoloxidase activity became unstable at pH lower than 5.5. The enzymatic extract obtained from viscera showed a higher affinity for catechol ( K M 5.97 mM) than carapace extract ( K M 19.40 mM). Both mono- and diphenoloxidase activities were found in carapace and viscera. Polyphenoloxidase and converted-hemocyanin into PPO-like enzyme could be the main responsible for these activities.

  • characterisation and tissue distribution of polyphenol oxidase of deepwater pink shrimp parapenaeus longirostris
    Food Chemistry, 2009
    Co-Authors: Josepablo Zamorano, Oscar Martinezalvarez, P Montero, M C Gomezguillen
    Abstract:

    Abstract Characterisation and tissue distribution of polyphenol oxidase (PPO) was studied in deepwater pink shrimp ( Parapenaeus longirostris ) post mortem. PPO activity was the highest in the carapace, followed by that in the abdomen exoskeleton, cephalotorax, pleopods and telson. No PPO activity was found in the abdomen muscle and in the pereopods and maxillipeds using the enzymatic assay. Storage of whole shrimps and of the different organs showed that melanosis (blackening) required the presence of the cephalotorax to be initiated, indicating that its development depends on other factors in addition to the PPO levels. Further characterisation was carried out in extracts partly purified using 40–70% ammonium sulfate fractionation. The enzyme had the highest activity at pH 4.5 and was most stable at pH 4.5 and 9.0. No clear maximum was observed in the 15–60 °C range but the higher stability was achieved at 30–35 °C. Apparent kinetic constants in the partly purified PPO from carapace were K M  = 1.85 mM and V max  = 38.5 U/mg of protein, pointing to a high affinity and reactivity of the enzyme when assayed with DOPA. Electrophoretic mobility was studied in native PAGE and non-reducing SDS–PAGE followed by staining with DOPA. Approximate MW of 500 kDa and 200 kDa were observed, respectively. These two forms could correspond to aggregates of minor PPO subunits that could not be resolved in these electrophoretic systems. The peptide mass fingerprinting obtained by MALDI-TOF analysis showed some peptides whose homology with hemocyanins and different PPO subunit precursors has already been demonstrated in the same species.

Hideki Kishimura - One of the best experts on this subject based on the ideXlab platform.

  • protein hydrolysates from pacific white shrimp Cephalothorax manufactured with different processes compositions characteristics and antioxidative activity
    Waste and Biomass Valorization, 2020
    Co-Authors: Sittichoke Sinthusamran, Soottawat Benjakul, Kongkarn Kijroongrojana, Thummanoon Prodpran, Hideki Kishimura
    Abstract:

    Hydrolysates from Pacific white shrimp (Litopenaeus vannamei) Cephalothorax were prepared using various hydrolysis processes, and their chemical composition, characteristics as well as antioxidative activity were studied. Those processes consisted of autolysis (AU), hydrolysis using Alcalase at 0.5% (0.5A) or 1.0% (1.0A) and autolysis, followed by Alcalase hydrolysis at 0.5 and 1.0% (AU + 0.5A and AU + 1.0A). All the hydrolysate samples had higher protein contents (86.04–89.24%) and lower amounts of ash (7.46–11.26%) and lipids (0.43–0.64%), compared to those of Cephalothorax (P < 0.05). The highest yield (54.04%) and protein recovery (84.15%) were observed in the AU + 1.0A sample, which had the maximum degree of hydrolysis (DH) (44.93%) (P < 0.05). All the hydrolysates had glutamic acid/glutamine (115.80–121.69 mg/g dry sample), aspartic acid/asparagine (84.04–90.28 mg/g dry sample), arginine (63.27–68.62 mg/g dry sample) and leucine (58.67–68.07 mg/g dry sample) as the dominant amino acids. Based on gel filtration chromatography, the hydrolysates with higher DH showed higher proportions of smaller peptides (< 1355 Da). When the antioxidant activities of the hydrolysates were determined, the AU + 1.0A sample had the highest ferrous ion chelating activity, ABTS radical scavenging activity and ORAC value, compared to the others (P < 0.05). However, the highest ferric reducing antioxidant activity and DPPH radical scavenging activity were obtained for the 1.0A and AU samples, respectively (P < 0.05). Furthermore, the AU + 1.0A sample showed higher inhibitory activity against DNA damage induced by peroxyl radicals than the 1.0A and AU samples. Therefore, different hydrolysis processes directly affected the protein recovery, chemical composition and antioxidant activities of the hydrolysates from shrimp Cephalothorax.

  • composition antioxidative and oxidative stability of mungoong a shrimp extract paste from the Cephalothorax of white shrimp
    Journal of Food Lipids, 2008
    Co-Authors: W Binsan, Soottawat Benjakul, Munehiko Tanaka, Wonnop Visessanguan, Sittiruk Roytrakul, Nandhsha Faithong, Hideki Kishimura
    Abstract:

    The chemical composition and antioxidative activity of mungoong, a shrimp extract paste from the Cephalothorax of white shrimp (Litopenaeus vannamei), were studied. Mungoong contained 42.3% polyunsaturated and 29.59% saturated fatty acid. It was rich in C20:5 n-3 (eicosapentaenoic acid) (4.31 g/100 g) and C22:6 n-3 (docosahexaenoic acid) (7.07 g/100 g). Mungoong consisted of Na (15.3 g/kg) and Ca (8.07 g/kg) as the major minerals. Fe and Cu were found at very low content. Glutamine was the most abundant amino acid, while lysine, alanine and asparagine were predominant in mungoong. Mungoong water extract at a level of 1,000 ppm exhibited antioxidative activity in a β-carotene–linoleic acid, lecithin liposome and comminuted fish model system. Antioxidative potential determined by 2,2-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) and 2,2-diphenyl-1-picrylhydrazyl radical-scavenging activities and ferric-reducing antioxidant power was quite stable during 8 weeks of storage at 4C and room temperature (28–30C). Antioxidative activities determined by all assays remained constant within the first week (P > 0.05). Thereafter, only slight decreases in activities were noticeable. During storage at both temperatures, mungoong's 2-thiobarbituric acid (TBA) values increased during the first 2 weeks of storage (P < 0.05), followed by the gradual decrease of 8 weeks. Nevertheless, no marked changes in TBA values were observed between samples kept at both storage temperatures. Thus, antioxidative peptides might contribute to the retardation of lipid oxidation of mungoong during the extended storage. PRACTICAL APPLICATIONS Mungoong, which is an extract paste from the Cephalothorax of white shrimp, was demonstrated to be a good source of protein, n-3 fatty acids as well as minerals. Additionally, mungoong could serve as a novel natural antioxidant with high stability. Therefore, mungoong produced from shrimp-processing by-products can be used as a neutraceutical product. This will lead to the full utilization of shrimp-processing waste and would reduce environmental problems associated with improper disposal of such wastes.

  • antioxidative activity of mungoong an extract paste from the Cephalothorax of white shrimp litopenaeus vannamei
    Food Chemistry, 2008
    Co-Authors: W Binsan, Soottawat Benjakul, Munehiko Tanaka, Wonnop Visessanguan, Sittiruk Roytrakul, Hideki Kishimura
    Abstract:

    Abstract The antioxidative activity of Mungoong, an extract paste, from the Cephalothorax of white shrimp ( Litopenaeus vannamei ) was studied. Extraction media were shown to affect the antioxidative activity and properties of resulting extracts from Mungoong. Distilled water exhibited the highest efficacy in extracting the antioxidants from Mungoong, as evidenced by the highest ABTS (2,2-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid)) and DPPH (2,2-diphenyl-1-picryl hydrazyl) radical scavenging activity as well as ferric reducing activity power (FRAP), compared with distilled water/ethanol mixture (1:1, 1:2 and 2:1) and ethanol. UV-absorbances at both 280 and 295 nm ( A 280 , A 295 ), browning intensity ( A 420 ) and fluorescence intensity were also highest in the extract using distilled water. ABTS and DPPH radical scavenging activity and FRAP of water extract, increased linearly with increasing concentration. Good correlation between ABTS and DPPH radical scavenging activity; DPPH radical scavenging activity and FRAP; ABTS radical scavenging activity and FRAP were observed, suggesting that antioxidants in the extract, possessed the capability of scavenging the radicals together with reducing power. Antioxidants in the water extract from Mungoong showed high stability over the wide pH ranges (2–11) and temperature up to 100 °C, in which the activity of more than 80% remained. MALDI-TOF analysis revealed that water extract contained the peptides having the mass ranges of m/z 400–1000 and 4000–7000.

P Montero - One of the best experts on this subject based on the ideXlab platform.

  • bioactive and technological functionality of a lipid extract from shrimp l vannamei Cephalothorax
    Lwt - Food Science and Technology, 2018
    Co-Authors: M C Gomezguillen, P Montero, M E Lopezcaballero, G C Baccan, Joaquin Gomezestaca
    Abstract:

    Abstract Lipid extract from shrimp Cephalothorax (LES) is a potential functional food ingredient because of its astaxanthin, α-tocopherol, and polyunsaturated fatty acid contents. This work aims at evaluating its bioactive (anti-inflammatory and antioxidant) and technological (potential for aqueous food applications) functionalities. LES was encapsulated by spray-drying, yielding a powder that was readily soluble in water. The resulting solution presented an attractive reddish colour, contrary to non-encapsulated LES. Encapsulated LES exerted anti-inflammatory activity at concentrations ≥100 μg/mL, as well as lipophilic and hydrophilic antioxidant activity. In contrast, non-encapsulated LES did not show any of these bioactivities when dissolved in water. Irrespective of processing temperature (20 °C/100 °C) or refrigerated storage time (up to 6 days at 5 °C ± 1 °C), the colour, astaxanthin content, and fatty acid composition of the encapsulated LES were relatively stable. Gelatin gels and films containing the emulsified or encapsulated LES had a homogeneous reddish colour, as well as minor physicochemical modifications (viscoelastic properties, gel strength, film water solubility, and water vapor permeability). Furthermore, the encapsulation process increased the bioaccessibility of astaxanthin to 100%, in comparison with non-emulsified LES-added samples. In conclusion, spray-dried encapsulated LES is a promising functional food ingredient, especially for aqueous applications.

  • the effect of high pressure treatment on functional components of shrimp litopenaeus vannamei Cephalothorax
    Innovative Food Science and Emerging Technologies, 2016
    Co-Authors: Joaquin Gomezestaca, P Montero, F Fernandezmartin, Marta Calvo, M C Gomezguillen
    Abstract:

    Abstract High-pressure (HP) technology has been applied to extend the shelf life of shrimps by inhibiting enzymes with PPO activity or microorganisms. However, there is very little information on its effect on relevant compounds from a nutritional or functional point of view, such as fatty acids, α-tocopherol, astaxanthin, and hemocyanin, which constitutes the main objective of the present work. Shrimp Cephalothoraxes were HP processed at 200, 400, or 600 MPa/18 °C/15 min or three consecutive 5 min cycles. It was found that hemocyanin was partially denatured at pressures up to 400 MPa, resulting in lower PPO activity, and it was totally denatured at 600 MPa, although 20% residual PPO activity remained. Astaxanthin, α-tocopherol, and total antioxidant activity were stable whichever HP treatment was applied, whereas 600 MPa caused a slight reduction of eicosapentaenoic acid (C20:5n3, EPA) and docosahexaenoic acid (C22:6n3, DHA). Despite this reduction, the ω -6/ ω -3 fatty acids ratio was very low (1). Industrial relevance Shrimps are high-value fishery products with a very short shelf life under refrigeration, mainly because of microbial growth and development of melanosis. Thermal treatment is effective for extending shelf life, but it affects the nutritional quality of shrimps through degradation of bioactives such as polyunsaturated fatty acids, tocopherols, or astaxanthin, which are mainly located in the Cephalothorax. High pressure is a non-thermal processing technology that has been proved to extend shrimp shelf life, but very little information can be found on its effect on the above-mentioned compounds as well as on the melanosis-inducing hemocyanin. Such basic knowledge is very important for industrial application of high-pressure technology to extend the shelf life of shrimps.

  • characterization of phenoloxidase activity of carapace and viscera from Cephalothorax of norway lobster nephrops norvegicus
    Lwt - Food Science and Technology, 2010
    Co-Authors: B Gimenez, Oscar Martinezalvarez, P Montero, M C Gomezguillen
    Abstract:

    Abstract The characterization of phenoloxidase activity was performed in both carapace and viscera extracts of Norway lobster. Phenoloxidase activity rose with increasing temperature up to 60 °C. The carapace enzymatic extract showed the highest themostability, retaining about 80% of maximum activity at 45 °C and 40% at 65 °C. On the other hand, both enzymatic extracts showed a single peak activity at neutral-slightly alkaline pH and were quite resistant to inactivation at alkaline pH (pH > 8), but phenoloxidase activity became unstable at pH lower than 5.5. The enzymatic extract obtained from viscera showed a higher affinity for catechol ( K M 5.97 mM) than carapace extract ( K M 19.40 mM). Both mono- and diphenoloxidase activities were found in carapace and viscera. Polyphenoloxidase and converted-hemocyanin into PPO-like enzyme could be the main responsible for these activities.

  • characterisation and tissue distribution of polyphenol oxidase of deepwater pink shrimp parapenaeus longirostris
    Food Chemistry, 2009
    Co-Authors: Josepablo Zamorano, Oscar Martinezalvarez, P Montero, M C Gomezguillen
    Abstract:

    Abstract Characterisation and tissue distribution of polyphenol oxidase (PPO) was studied in deepwater pink shrimp ( Parapenaeus longirostris ) post mortem. PPO activity was the highest in the carapace, followed by that in the abdomen exoskeleton, cephalotorax, pleopods and telson. No PPO activity was found in the abdomen muscle and in the pereopods and maxillipeds using the enzymatic assay. Storage of whole shrimps and of the different organs showed that melanosis (blackening) required the presence of the cephalotorax to be initiated, indicating that its development depends on other factors in addition to the PPO levels. Further characterisation was carried out in extracts partly purified using 40–70% ammonium sulfate fractionation. The enzyme had the highest activity at pH 4.5 and was most stable at pH 4.5 and 9.0. No clear maximum was observed in the 15–60 °C range but the higher stability was achieved at 30–35 °C. Apparent kinetic constants in the partly purified PPO from carapace were K M  = 1.85 mM and V max  = 38.5 U/mg of protein, pointing to a high affinity and reactivity of the enzyme when assayed with DOPA. Electrophoretic mobility was studied in native PAGE and non-reducing SDS–PAGE followed by staining with DOPA. Approximate MW of 500 kDa and 200 kDa were observed, respectively. These two forms could correspond to aggregates of minor PPO subunits that could not be resolved in these electrophoretic systems. The peptide mass fingerprinting obtained by MALDI-TOF analysis showed some peptides whose homology with hemocyanins and different PPO subunit precursors has already been demonstrated in the same species.

Montse Perez - One of the best experts on this subject based on the ideXlab platform.

  • prey capture ingestion and digestion dynamics of octopus vulgaris paralarvae fed live zooplankton
    Frontiers in Physiology, 2017
    Co-Authors: M Nande, Pablo Presa, Alvaro Roura, Paul L R Andrews, Montse Perez
    Abstract:

    Octopus vulgaris is a species of great interest in research areas such as neurobiology, ethology and ecology but is also a candidate species for aquaculture as food resource as well as source to alleviating the fishing pressure on its wild populations. This study aimed to characterize the predatory behaviour of O. vulgaris paralarvae and to quantify their digestive activity. Those processes were affordable using the video-recording analysis of 3 dph, mantle-transparent paralarvae feeding on 18 types of live zooplanktonic prey. We show that octopus paralavae attack, immobilize, drill and ingest live cladocerans and copepods with 100% efficiency, which decreases dramatically to 60% on decapod prey (Pisidia longicornis). The majority (85%) of successful attacks targeted the prey Cephalothorax while unsuccessful attacks either targeted the dorsal Cephalothorax or involved prey defensive strategies (e.g. juvenile crab megalopa) or prey protected by thick carapaces (e.g. Gammaridae). After immobilization, the beak, the buccal mass and the radula were involved in exoskeleton penetration and content ingestion. Ingestion time of prey content was rapid for copepods and cladocerans (73.13 ± 23.34 s) but much slower for decapod zoeae and euphasiids (152.49 ± 29.40 s). Total contact time with prey was always <5min. Contrary to the conventional view of crop filling dynamics observed in adult Octopus vulgaris, food accumulated first in the stomach of paralarvae and the crop filled after the stomach volume plateaued. Peristaltic crop contractions (~18/min) moved food into the stomach (contractions ~30/min) from where it passed to the caecum. Pigmented food tracers were seen to enter the digestive gland, 312 ± 32 s after the crop reached its maximum volume. Digestive tract contents passed into the terminal intestine by peristalsis (contraction frequency ~50/min) and defaecation was accompanied by an increased frequency of mantle contractions. Current results provide novel insights into both, O. vulgaris paralarvae – live prey capture strategies and the physiological mechanisms following ingestion, a key information to develop an effective rearing protocol for O. vulgaris.

  • Prey Capture, Ingestion, and Digestion Dynamics of Octopus vulgaris Paralarvae Fed Live Zooplankton
    Frontiers Media S.A., 2017
    Co-Authors: M Nande, Pablo Presa, Alvaro Roura, Paul L R Andrews, Montse Perez
    Abstract:

    Octopus vulgaris is a species of great interest in research areas such as neurobiology, ethology, and ecology but also a candidate species for aquaculture as a food resource and for alleviating the fishing pressure on its wild populations. This study aimed to characterize the predatory behavior of O. vulgaris paralarvae and to quantify their digestive activity. Those processes were affordable using the video-recording analysis of 3 days post-hatching (dph), mantle-transparent paralarvae feeding on 18 types of live zooplanktonic prey. We show for the first time in a live cephalopod that octopus paralarvae attack, immobilize, drill, and ingest live cladocerans and copepods with 100% efficiency, which decreases dramatically to 60% on decapod prey (Pisidia longicornis). The majority (85%) of successful attacks targeted the prey Cephalothorax while unsuccessful attacks either targeted the dorsal Cephalothorax or involved prey defensive strategies (e.g., juvenile crab megalopae) or prey protected by thick carapaces (e.g., gammaridae amphipods). After immobilization, the beak, the buccal mass and the radula were involved in exoskeleton penetration and content ingestion. Ingestion time of prey content was rapid for copepods and cladocerans (73.13 ± 23.34 s) but much slower for decapod zoeae and euphausiids (152.49 ± 29.40 s). Total contact time with prey was always <5 min. Contrary to the conventional view of crop filling dynamics observed in adult O. vulgaris, food accumulated first in the stomach of paralarvae and the crop filled after the stomach volume plateaued. Peristaltic crop contractions (~18/min) moved food into the stomach (contractions ~30/min) from where it passed to the caecum. Pigmented food particles were seen to enter the digestive gland, 312 ± 32 s after the crop reached its maximum volume. Digestive tract contents passed into the terminal intestine by peristalsis (contraction frequency ~50/min) and defaecation was accompanied by an increased frequency of mantle contractions. Current results provide novel insights into both, O. vulgaris paralarvae—live prey capture strategies and the physiological mechanisms following ingestion, providing key information required to develop an effective rearing protocol for O. vulgaris paralarvae