RESUMO
Background: Microplastics (MPs) are pervasive pollutants in the marine environment, exhibiting persistence in coastal sediment over extended periods. However, the mechanism of their uptake by marine organisms and distribution in habitat is less understood. The objective of the present study was to investigate the presence of MP contamination in burrow sediment, feeding pellets, and tissue of Dotilla blanfordi in the Gulf of Kachchh, Gujarat State. Methods: A total of 500 g of burrow sediment, 100 g of feeding pellets, and body tissue of 10 resident D. blanfordi were pooled as one replica. Such seven replicas from each site were analyzed for MP extraction from three sites, including Asharmata, Mandvi, and Serena, located in the Gulf of Kachchh. The standard protocol was used during the analysis of the collected samples in order to isolate MPs. Results: The abundance of MP was found higher in burrow sediment, feeding pellets and tissue of D. blanfordi at study site Mandvi, followed by Serena and Asharmata. The abundance of MP was found higher in D. blanfordi tissue, followed by burrow sediment and feeding pellet. A significant variation was observed in MP abundance among burrow sediment, feeding pellets, and tissue. MPs with various shapes (fiber, film, and fragment), sizes (1-2, 2-3, 3-4, and 4-5 mm), and colors (blue, green, black, pink, purple, red transparent) were recorded from all the study sites. Polyurethane and polyvinyl chloride were recognized as the chemical profile of the extracted MPs. The current investigation revealed greater accumulation of MPs in D. blanfordi's tissues compared to sediment and pellets, suggesting a risk of MP contamination in marine benthic fauna with a greater rate of bioaccumulation. D. blanfordi plays a significant role as a structuring agent for MP distribution in the intertidal flat through burrowing activity.
Assuntos
Braquiúros , Sedimentos Geológicos , Microplásticos , Poluentes Químicos da Água , Animais , Sedimentos Geológicos/química , Microplásticos/análise , Braquiúros/química , Poluentes Químicos da Água/análise , Monitoramento Ambiental/métodos , Praias , ÍndiaRESUMO
Sinopotamon Henanense expresses two metalâinduced metallothioneins (MTs), Cdâinduced MT and Cuâinduced MT (ShCuMT). The Cdâinduced MT has been characterized as a Cdâthiolate MT. However, it is unknown whether ShCuMT is a Cuâthiolate MT. In the present study, ShCuMT was expressed heterologously in Escherichia coli and purified by NiâNTA column and superdexâ75 column. And its metalâbinding feature was evaluated by DTNB reaction, circular dichroism spectroscopy (CD), isothermal microtitration (ITC), electrospray flight mass spectrometry (ESIâTOFâMS), and matrixâassisted laser desorption ionization flight mass spectrometry (MALDIâTOFâMS). Bioinformatics analysis demonstrated that ShCuMT possessed the cysteineâtriplet motif of a Cuâspecific MT. Expression and purification of ShCuMT illustrated that SUMO tag used as the production system for ShCuMT resulted in a high production yield. The stability order of ShCuMT binding metal ions were Cu (â ) > Cd (â ¡) > Zn (â ¡). The CD spectrum indicated that ShCuMT binding with Cu (I) exhibited a compact thiol metal clusters structure. Besides, there emerged no a visible nickelâthiol absorption after NiâNTA column affinity chromatography. The ITC results implied that CuâShCuMT possessed the optimal thermodynamic conformation and the highest stoichiometric number of Cu (â ). Overall, the results suggested that SUMO fusion system is a robust and inexpensive approach for ShCuMT expression and NiâNTA column had no influence on metal binding of ShCuMT and Cu(â ) was considered its cognate metal ion, and ShCuMT possessed canonical Cuâthiolate characteristics. The metal binding feature of ShCuMT reported here contributes to elucidating the structureâfunction relationship of ShCuMT in S. Henanense.
Assuntos
Cobre , Metalotioneína , Metalotioneína/genética , Metalotioneína/química , Metalotioneína/metabolismo , Metalotioneína/isolamento & purificação , Animais , Cobre/metabolismo , Cobre/química , Braquiúros/genética , Braquiúros/metabolismo , Braquiúros/química , Proteínas de Artrópodes/genética , Proteínas de Artrópodes/química , Proteínas de Artrópodes/metabolismo , Cádmio/metabolismo , Cádmio/química , Escherichia coli/genética , Escherichia coli/metabolismo , Sequência de Aminoácidos , Ligação Proteica , Proteínas Recombinantes/química , Proteínas Recombinantes/genética , Proteínas Recombinantes/metabolismo , Proteínas Recombinantes/isolamento & purificação , Proteínas Recombinantes/biossínteseRESUMO
Lectins are versatile proteins that specifically recognize and interact with sugar moieties expressed on the cell surface. The potential of lectin in drug targeting and delivery has instigated interest to identify natural lectins. Crabs have been identified as a rich source of lectin because the innate immune system is activated on encounter of pathogens and helps in the production of lectin. Although the presence of lectins in crab's hemolymph is well documented, little information about lectin in hepatopancreas, a vital organ for immunity and digestion in crustaceans, is currently available. A calcium dependent lectin (75 kDa) was purified from the hepatopancreas of the freshwater crab Oziotelphusa naga by bioadsorption and fetuin linked Sepharose 4B affinity chromatography technique. The isolated hepatopancreas lectin is calcium dependent and maximum agglutination was observed with rabbit erythrocytes. The hemagglutinating activity of the hepatopancreas lectin was effectively inhibited by sugars, such as α-lactose, GlcNAc, trehalose and NeuAc. Compared to sialylated N-glycosylated proteins including transferrin and apo transferrin, sialylated O-glycosylated proteins like fetuin exhibited stronger inhibitory effect. The ability of erythrocytes to bind hepatopancreas lectin has been diminished by desialylation of the potent inhibitor, indicating the significance of sialic acid in lectin-ligand interactions. The purified hepatopancreas lectin showed a broad spectrum of antimicrobial activity against bacteria Staphylococcus aureus, Klebsiella pneumoniae, Proteus mirabilis, Pseudomonas aeruginosa, E. coli and fungi Candida albicans and Aspergillus niger. The findings of this study demonstrate the significance of hepatopancreas lectin as a multifunctional defense protein that inhibits the growth of bacteria and fungi.
Assuntos
Braquiúros , Hepatopâncreas , Lectinas , Animais , Hepatopâncreas/química , Lectinas/farmacologia , Lectinas/química , Lectinas/isolamento & purificação , Braquiúros/química , Proteínas de Artrópodes/farmacologia , Proteínas de Artrópodes/química , Proteínas de Artrópodes/isolamento & purificação , Proteínas de Artrópodes/genética , Anti-Infecciosos/farmacologia , Anti-Infecciosos/química , Anti-Infecciosos/isolamento & purificação , Coelhos , Eritrócitos/efeitos dos fármacos , Candida albicans/efeitos dos fármacosRESUMO
Aroma is one of the most noticeable characteristics when consuming Chinese mitten crab (Eriocheir sinensis) and is crucial for consumer satisfaction and the development of industry. In this study, we utilized fingerprints and the sensomics approach to analyze volatiles in the hepatopancreas of E. sinensis from Chongming and Taixing. GC-IMS indicated that the odor profile was dominated by pungent (-), buttery (+), and fruity (+) from Chongming and was more prone to alcoholic (-), solvent (-), and aldehydic (+) in Taixing. Moreover, PLS-DA modeling identified 2-acetylthiazole and toluene as the primary differential compounds. Subsequently, fifteen active-aroma compounds with FD values of >4 was recombined in an odorless matrix to simulate the odor profile of the hepatopancreas. Notably, removing methional may significantly decrease the intensity of the fatty and toasted odors. The findings reveal the odor profile of hepatopancreas and establish a theoretical foundation for subsequent studies on flavor.
Assuntos
Braquiúros , Cromatografia Gasosa-Espectrometria de Massas , Hepatopâncreas , Odorantes , Compostos Orgânicos Voláteis , Animais , Odorantes/análise , Hepatopâncreas/química , Hepatopâncreas/metabolismo , Braquiúros/química , Compostos Orgânicos Voláteis/químicaRESUMO
Both sedative and antipathogenic drugs are often found to be illegally used in aquaculture, but there is a lack of simultaneous monitoring methods. A method for simultaneously monitoring multiple prohibited drugs in various aquatic product samples was developed in this work, including fish, shrimp, crab, and shellfish. Sulfonic acid-functionalized magnetic graphitic carbon nitride (S-MGCN) was synthesized and validated to efficiently co-extract all targets (adsorption efficiency over 90.07%) through various adsorption mechanisms such as electrostatic interaction, hydrogen bonding, and π-π interaction while demonstrating good sample matrix purification ability (matrix effect below 13.60%). A new magnetic solid-phase extraction method based on S-MGCN was subsequently established. Coupled with UPLC-MS/MS, the detection limits were 0.030.075 µg /kg, and the recoveries ranged from 88.76% to 111.74% with the RSDs lower than 14.60%, indicating that the developed method has good sensitivity, accuracy, and precision. Further validation of its practicality was achieved through actual sample analysis.
Assuntos
Peixes , Contaminação de Alimentos , Alimentos Marinhos , Frutos do Mar , Extração em Fase Sólida , Espectrometria de Massas em Tandem , Animais , Extração em Fase Sólida/métodos , Contaminação de Alimentos/análise , Alimentos Marinhos/análise , Frutos do Mar/análise , Cromatografia Líquida de Alta Pressão , Adsorção , Poluentes Químicos da Água/análise , Poluentes Químicos da Água/química , Braquiúros/químicaRESUMO
Physicochemical properties and protein alterations in Ovalipes punctatus during cold-chain transportation were examined via sensory scores, water-holding capacity (WHC), glucose (GLU) content, catalase (CAT) activity, urea nitrogen (UN) content, and tandem mass tag (TMT)-based proteomic analysis. The results revealed that sensory characteristics and texture of crab muscle deteriorated during transportation. Proteomic analysis revealed 442 and 470 different expressed proteins (DEPs) in crabs after 18 h (FC) and 36 h (DC) of transportation compared with live crabs (LC). Proteins related to muscle structure and amino acid metabolism significantly changed, as evidenced by the decreased WHC and sensory scores of crab muscle. Glycolysis, calcium signaling, and peroxisome pathways were upregulated in the FC/LC comparison, aligning with the changes in GLU content and CAT activity, revealing the stress response of energy metabolism and immune response in crabs during 0-18 h of transportation. The downregulated tricarboxylic acid (TCA) cycle and carcinogenesis-reactive oxygen species pathways were correlated with the decreasing trend in CAT activity, suggesting a gradual retardation in both energy and antioxidant metabolism in crabs during 18-36 h of transportation. Furthermore, the regulated purine nucleoside metabolic and nucleoside diphosphate-related processes, with the increasing changes in UN content, revealed the accumulation of metabolites in crabs.
Assuntos
Braquiúros , Músculos , Proteômica , Animais , Braquiúros/metabolismo , Braquiúros/química , Músculos/metabolismo , Músculos/química , Meios de Transporte , Frutos do Mar/análise , Temperatura Baixa , Espectrometria de Massas em Tandem , Alimentos Marinhos/análiseRESUMO
Scy p 8 (triosephosphate isomerase) as a crab allergen in inducing distinct T-helper (Th) cell differentiation and a linear epitope associated with allergenicity remain elusive. In this study, mice sensitized with Scy p 8 exhibited significantly upregulated levels of IgE, IgG1, and IL-4 release, inducing a Th2 immune response. Moreover, the release of IFN-γ (Th1) and the levels of Treg cells were downregulated, while IL-17A (Th17) was upregulated, indicating that Scy p 8 disrupted the Th1/Th2 balance and Th17/Treg balance in mice. Furthermore, bioinformatics prediction and serum samples from crab-allergic patients and mice enabled the discovery of 8 linear epitopes of Scy p 8. Meanwhile, the analysis of peptide similarity and tertiary superposition revealed that 8 epitopes of Scy p 8 exhibited conservation across various species, potentially resulting in cross-reactivity. These findings possess the potential to enhance the comprehension of crab allergens, thereby establishing a foundation for investigating cross-reactivity.
Assuntos
Alérgenos , Braquiúros , Epitopos , Camundongos Endogâmicos BALB C , Animais , Braquiúros/imunologia , Braquiúros/genética , Braquiúros/química , Alérgenos/imunologia , Alérgenos/química , Alérgenos/genética , Humanos , Epitopos/imunologia , Epitopos/química , Camundongos , Feminino , Hipersensibilidade a Frutos do Mar/imunologia , Imunoglobulina E/imunologia , Proteínas de Artrópodes/imunologia , Proteínas de Artrópodes/genética , Proteínas de Artrópodes/química , Imunoglobulina G/imunologia , Imunoglobulina G/sangue , Células Th2/imunologia , Reações Cruzadas , Masculino , Interleucina-4/imunologia , Interleucina-4/genética , Adulto , Células Th1/imunologia , Interferon gama/imunologia , Interferon gama/genéticaRESUMO
The present research study combines chitin from shrimp waste with the oxide-rich metakaolin. Metakaolin is a blend of mixed oxides rich in silica and alumina with good adsorbent properties. The chitin@metakaolin (CHt@M.K.) composite was synthesized and characterized using FTIR, SEM, TGA, XRD and XPS techniques. Cr(VI) removal studies were compared for chitin and CHt@M.K. through adsorption. It was found that the adsorption capacity of CHt@M.K. is 278.88 mg/g, almost double that of chitin, at pH 5.0 in just 120 min of adsorption. Isotherm models like Langmuir, Freundlich, Temkin and Dubinin-Radushkevich were investigated to comprehend the adsorption process. It was revealed that Langmuir adsorption isotherm is most suitable to elucidate Cr(VI) adsorption on CHt@M.K. The adsorption kinetics indicate that pseudo first order was followed, indicating that the physisorption was the process that limited the sorption process rate. The positive enthalpy change (20.23 kJ/mol) and positive entropy change (0.083 kJ/mol K) showed that the adsorption process was endothermic and more random at the solid-liquid interface. The negative free energy change over entire temperature range was an indicator of spontaneity of the process. Apart from all these, the non-covalent interactions between Cr(VI) and composite were explained by quantum calculations based models.
Assuntos
Exoesqueleto , Quitina , Cromo , Poluentes Químicos da Água , Quitina/química , Animais , Cromo/química , Adsorção , Poluentes Químicos da Água/química , Exoesqueleto/química , Braquiúros/química , CinéticaRESUMO
Geographical traceability plays a crucial role in ensuring quality assurance, brand establishment, and the sustainable development of the crab industry. In this study, we examined the possibility of using gas chromatography-ion mobility spectrometry with multivariate statistical authenticity analysis to identify the origin of crabs from five sites downstream of the Yangtze River. Significant variations were observed in the levels of alcoholic flavor compounds in the hepatopancreas and muscles of crabs from different geographical locations, and a support vector machine exhibited discriminant ability with 100% accuracy. These flavor variations exhibited significant correlations with the types and concentrations of elements within the crabs, as well as with free amino acids. This study offers a practical approach for determining the geographical traceability of Chinese mitten crabs and elucidates the role of elements in flavor modulation, thereby providing innovative strategies to enhance the efficiency of crab farming.
Assuntos
Braquiúros , Frutos do Mar , Animais , Braquiúros/química , Braquiúros/classificação , China , Frutos do Mar/análise , Aromatizantes/química , Aromatizantes/análise , Cromatografia Gasosa-Espectrometria de Massas , Controle de Qualidade , Paladar , Geografia , Hepatopâncreas/químicaRESUMO
The quantity of snow crabs (Chionoecetes opilio) harvested in Korea is subject to seasonal restrictions; therefore, snow crabs are imported from Russia. Metabolites in snow crabs from two geographic origins were compared. The metabolites were subjected to metabolomic analysis to prevent fraudulent sales of marine products from a particular country. Capillary electrophoresis time-of-flight mass spectrometry was used. Seventy-seven target metabolites were identified using a mass spectral library. Through orthogonal partial least squares discriminant analysis, the top 25 biomarker candidates were evaluated based on p-values and fold changes. A total of 246 peaks (187 and 59 in the cation and anion modes, respectively) were identified. Among the biomarker candidates, 2-oxovaleric acid, asymmetric dimethylarginine, hypotaurine, and allo-threonine were selected as final biomarkers to unequivocally determine the geographic origin. Overall, metabolic analyses allowed us to differentiate snow crabs from different geographic origins. This method could also be extended of other marine products.
Assuntos
Biomarcadores , Braquiúros , Eletroforese Capilar , Metabolômica , Animais , Biomarcadores/análise , Biomarcadores/metabolismo , Braquiúros/química , Braquiúros/metabolismo , Braquiúros/classificação , Federação Russa , República da Coreia , Espectrometria de Massas , Análise Discriminante , Frutos do Mar/análiseRESUMO
Crab meatballs with more unsaturated fat tend to spoil. Ginger essential oil (GEO) with oxidation resistance was encapsulated into microcapsules (GM) by complex cohesion of mung bean protein isolate (MBPI) and chitosan (CS) in a ratio of 8:1 at pH = 6.4, encapsulation efficiency (EE) and payload (PL) of GM (D50 = 26.16 ± 0.45 µm) with high thermal stability were 78.35 ± 1.02% and 55.43 ± 0.64%. GM (0.6%, w/w) did not interfere with the original flavor of crab meatballs, and lowered values of pH, thiobarbituric acid reactive substances (TBARS) and total bacteria counts (TBC) of the products than those spiked with GEO and the control. The prediction accuracy of the logistic first-order growth kinetic equation in line with TBC (2.84%) was better than that of zero-order and Arrhenius coupled equation based on pH (7.48%) and TBARS (5.94%), but all of them could predict the shelf life of crab meatballs containing GM stored at 4-25 °C.
Assuntos
Quitosana , Composição de Medicamentos , Conservação de Alimentos , Armazenamento de Alimentos , Óleos Voláteis , Vigna , Zingiber officinale , Quitosana/química , Óleos Voláteis/química , Óleos Voláteis/farmacologia , Animais , Conservação de Alimentos/métodos , Zingiber officinale/química , Vigna/química , Vigna/crescimento & desenvolvimento , Proteínas de Plantas/química , Braquiúros/química , Braquiúros/microbiologia , Frutos do Mar/análise , Frutos do Mar/microbiologiaRESUMO
This investigation aimed to scrutinize the chemical and structural analogies between chitosan extracted from crab exoskeleton (High Molecular Weight Chitosan, HMWC) and chitosan obtained from mushrooms (Mushroom-derived Chitosan, MRC), and to assess their biological functionalities. The resulting hydrolysates from the hydrolysis of HMWC by chitosanase were categorized as chitosan oligosaccharides (csCOS), while those from MRC were denoted as mrCOS. The molecular weights (MW) of csCOS and mrCOS were determined using Matrix-Assisted Laser Desorption Ionization Time-of-Flight (MALDI-TOF) mass spectrometry. Furthermore, structural resemblances of csCOS and mrCOS were assessed utilizing X-ray powder diffraction (XRD) and Fourier transform infrared (FT-IR) spectroscopy. Intriguingly, no apparent structural disparity between csCOS and mrCOS was noted in terms of the glucosamine (GlcN) and N-acetylglucosamine (GlcNAc) composition ratios. Consequently, the enzymatic activities of chitosanase for HMWC and MRC exhibited remarkable similarity. A topological examination was performed between the enzyme and the substrate to deduce the alteration in MW of COSs following enzymatic hydrolysis. Moreover, the evaluation of antioxidant activity for each COS revealed insignificance in the structural disparity between HMWC and MRC. In summary, grounded on the chemical structural similarity of HMWC and MRC, we propose the potential substitution of HMWC with MRC, incorporating diverse biological functionalities.
Assuntos
Agaricales , Exoesqueleto , Braquiúros , Quitosana , Peso Molecular , Quitosana/química , Braquiúros/química , Exoesqueleto/química , Animais , Hidrólise , Agaricales/química , Agaricales/enzimologia , Glicosídeo Hidrolases/química , Glicosídeo Hidrolases/metabolismo , Antioxidantes/química , Antioxidantes/farmacologia , Antioxidantes/isolamento & purificação , Espectroscopia de Infravermelho com Transformada de Fourier , Difração de Raios X , Estrutura MolecularRESUMO
Hystrix brach yura bezoar is calcified undigested material found in the gastrointestinal tract known for various medicinal benefits including as an anticancer agent. However, the H. brachyura population has been declining due to its demand and is under Malaysian law pro tection. Therefore, present study aimed to identify bezoar anticancer active compounds through metabolomics and in - silico approaches. Five replicates of bezoar powder were subjected to extraction using different solvent ratios of methanol - water (100, 75, 5 0, 25, 0% v/v). Cytotoxicity and metabolite profiling using liquid chromatography - mass spectrometry were conducted. Putative compounds identified were subjected to in - silico analysis with targeted anticancer proteins namely, Bcl - 2, Cyclin B/CDK1 complex, V EGF and NM23 - H1. The correlation of LC - MS and cytotoxicity profile pinpointed two compounds, mangiferin and propafenone. In - silico study showed both compounds exerted good binding scores to all proteins with hydrophobic interaction dominating the ligand - pr otein complex binding, suggesting the ligands act as hydrophobes in the interactions.
El bezpar de Hystrix branchyura es material calcificado sin digerir encontr ados en el tracto gastrointestinal, conocido por sus variados beneficios médicos, incluyendo propiedades anticancerosas. De todas formas, la población de H. Branchyura ha ido declinando debido a su demanda y está bajo la protección de la ley de Malasia. Po r esto, este estudio busca identificar los componentes activos anticancerosos del bezoar mediante abordajes metabolómico e in silico. Cinco réplicas de polvo de bezoar fueron sometidos a extracción usando solventes con diferentes proporciones metanol - agua (100, 75, 50, 25, 0% v/v). Se hicieron perfiles de citotoxicidad y de metabolitos usando cromatografía líquida - espectrometría de masa ( LC - MS ). Se identificaron compuestos putativos yse sometieron a a nálisis in silico, buscando las proteínas anticancerosas B cl - 2, complejo Cyclin B/CDK1, VEGF, y NM23 - H1. La correlación LC - MS y el perfil de citotoxicidad identificaron dos compuestos: mangiferina y propafenona. El estudio in silico mostró que ambos compuestos tenían buenos índices de enlace con todas las proteín as con interacción hidrofóbica dominando el enlace complejo proteína - ligando, sugeriendo que los ligandos actúan como hidrófobos en las interacciones
Assuntos
Bezoares/metabolismo , Braquiúros/química , Bezoares/tratamento farmacológico , Espectrometria de Massa com Cromatografia Líquida , Neoplasias/tratamento farmacológicoRESUMO
Neuropeptides have tremendous potential for application in modern medicine, including utility as biomarkers and therapeutics. To overcome the inherent challenges associated with neuropeptide identification and characterization, data-independent acquisition (DIA) is a fitting mass spectrometry (MS) method of choice to achieve sensitive and accurate analysis. It is advantageous for preliminary neuropeptidomic studies to occur in less complex organisms, with crustacean models serving as a popular choice due to their relatively simple nervous system. With spectral libraries serving as a means to interpret DIA-MS output spectra, and Cancer borealis as a model of choice for neuropeptide analysis, we performed the first spectral library mapping of crustacean neuropeptides. Leveraging pre-existing data-dependent acquisition (DDA) spectra, a spectral library was built using PEAKS Online. The library is comprised of 333 unique neuropeptides. The identification results obtained through the use of this spectral library were compared with those achieved through library-free analysis of crustacean brain, pericardial organs (PO), and thoracic ganglia (TG) tissues. A statistically significant increase (Student's t-test, P value < 0.05) in the number of identifications achieved from the TG data was observed in the spectral library results. Furthermore, in each of the tissues, a distinctly different set of identifications was found in the library search compared to the library-free search. This work highlights the necessity for the use of spectral libraries in neuropeptide analysis, illustrating the advantage of spectral libraries for interpreting DIA spectra in a reproducible manner with greater neuropeptidomic depth.
Assuntos
Espectrometria de Massas , Neuropeptídeos , Animais , Neuropeptídeos/análise , Espectrometria de Massas/métodos , Braquiúros/química , Braquiúros/metabolismo , Biblioteca de Peptídeos , Proteômica/métodos , Crustáceos/química , Bases de Dados de ProteínasRESUMO
This study investigates the concentration of metals in the different developmental phases of the gonads of Ucides cordatus from mangrove areas of Vila do Bacuriteua on the Bragança Peninsula, Caeté-Taperaçu Marine Extractive Reserve, state of Pará, on the Brazilian Amazon coast. Elemental analysis was determined by inductively coupled plasma optical emission spectrometry (ECP-OES). Metal concentration in males ranged from Cd = 0.04 to Cu = 2.27 mg kg-1 ww in the Developing and Developed gonadal stages, respectively. In females it was from Cd = 0.11 to Cu = 8.43 mg kg-1 ww only in the Developed stage). The elements Cr and Pb, for both sexes, presented concentrations above the limits allowed by the Brazilian regulatory body and only Pb by the international agencies, revealing a higher degree of contamination of these metals in the gonads of the mangrove crabs. Increasing mangrove crab consumption amplifies the risks of metal contamination among the human population and may cause public health problems.
Assuntos
Braquiúros , Metais Pesados , Poluentes Químicos da Água , Masculino , Humanos , Animais , Feminino , Braquiúros/química , Cádmio/análise , Chumbo/análise , Monitoramento Ambiental/métodos , Poluentes Químicos da Água/análise , Biomarcadores/análise , Metais Pesados/análiseRESUMO
The objective of this study was to compare the effect of freezing and heating treatment sequences on the biochemical properties and flavor of crab (Portunus trituberculatus) meat during freeze-thaw cycles. The results showed that pH, color, K and microstructure changes in the H-F group were not significant with increasing number of freeze-thaw cycles, but TVB-N values increased and WHC values decreased. However, with the increase in the number of freeze-thaw cycles, pH and WHC significantly decreased and TVB-N, L* and K values significantly increased in the C and F-H groups. Proteins were degraded in all groups, but the lower degree of degradation occurred in the H-F group. Although the total free amino acid content decreased with increasing number of freeze-thaw cycles in each group, the high content of AMP and IMP in the H-F group suggested that it still had a better flavor.
Assuntos
Braquiúros , Animais , Congelamento , Braquiúros/química , Natação , Calefação , Carne/análiseRESUMO
We studied the depuration mechanisms of metals (Cd, Cu, Pb, Zn, Mn, Ni, Cr, Fe) in Neohelice granulata, from sites with different human impacts (PC, a more impacted site and VM, a less impacted one). Our objectives included assessing metal concentrations (essential and non-essential) before and after depuration treatment, evaluating biochemical biomarkers (non-enzymatic and enzymatic) pre and post-treatment, and determining the role of metal-rich granules (MRG) in depuration. We observed variability in metals and biomarkers post-depuration, with no significant differences observed in PC, while Cd and Mn increased and Ni, Cu, and Fe decreased in VM. Integrated biomarkers' response indicated the prevailing antioxidant capacity in depurated organisms. Lipid peroxidation changes were insignificant, except in depurated-VM where values increased. MRG showed a significant decrease only for Mn and Fe, suggesting they were not the primary depuration structure. We concluded that depuration might depend on the species, gender and contamination history.
Assuntos
Braquiúros , Metais Pesados , Poluentes Químicos da Água , Animais , Humanos , Metais Pesados/análise , Braquiúros/química , Cádmio , Bioacumulação , Poluentes Químicos da Água/análise , Monitoramento Ambiental , BiomarcadoresRESUMO
Green extraction methods using a combination of mechanical, enzymatic, and green chemical treatments were evaluated for the sequential extraction of carotenoid pigments, protein, and chitin from crab processing discards. Key objectives included avoiding the use of hazardous chemical solvents, conducting as close to a 100% green extraction as possible, and developing simple processes to facilitate implementation into processing plants without the need for complicated and expensive equipment. Three crab bio-products were obtained: pigmented vegetable oil, pigmented protein powder, and chitin. Carotenoid extractions were performed using vegetable oils (corn, canola, and sunflower oils), giving between 24.85% and 37.93% astaxanthin recovery. Citric acid was used to demineralize the remaining material and afforded a pigmented protein powder. Three different proteases were used to deproteinate and isolate chitin in yields between 17.06% and 19.15%. The chitin was still highly colored and therefore decolorization was attempted using hydrogen peroxide. Characterization studies were conducted on each of the crab bio-products isolated including powder X-ray diffraction analysis on the chitin (80.18% crystallinity index, CI, achieved using green methods). Overall, three valuable bio-products could be obtained but further research is needed to obtain pigment-free chitin in an environmentally friendly manner.
Assuntos
Braquiúros , Animais , Braquiúros/química , Pós , Proteínas , Peptídeo Hidrolases , Quitina/químicaRESUMO
The study investigates some biological indices and chemical compositions of Callinectes amnicola and their potential for reuse in the context of the circular economy paradigm. The total of 322 mixed-sex C. amnicola collected over a period of six months was examined. The morphometric and meristic characteristics were estimated for biometric assessment. The gonads were obtained from the female crabs for gonadosomatic indices. The shell was obtained using the hand removal technique by detaching it from the crab body. The edible and shell portions were processed separately and subjected to chemical analysis. Our findings showed that females had the highest sex ratio across the six months. The slope values (b) for both sexes exhibited negative allometric growth across all months since the slope values obtained were less than 3 (b < 3). The values obtained for Fulton's condition factor (K) of crabs in all examined months were greater than 1. The edible portion had the highest moisture level at 62.57 ± 2.16% and varied significantly (P < 0.05). The high amount of total ash obtained in the shell sample showed that ash is the main mineral present in crab shells and showed a significant difference (P < 0.05). The shell sample had the highest concentrations of Na and CaCO3. Based on the findings of this study, it was observed that the shell waste contains some essential and transitional minerals (Ca, CaCO3, Na, and Mg) and can be utilized as catalysts in several local and industrial applications, such as pigments, adsorbents, therapeutics, livestock feeds, biomedical industries, liming, fertilization, and so on. Proper valorization of this shell waste should be encouraged rather than discarding it.
Assuntos
Braquiúros , Exoesqueleto Energizado , Gastrópodes , Animais , Masculino , Feminino , Braquiúros/química , BiometriaRESUMO
The purpose of this article is to design a green and comprehensive utilization process for preparing chitosan from crab shells. Glutamate acid was used as a decalcifying agent for crab shells, and the mixed solution of potassium hydroxide/isopropanol was used for deproteinization and deacetylation to prepare chitosan. Glutamic acid and isopropanol could be recovered for recycling. At the same time, calcium carbonate and protein in crab shells were converted into calcium hydrogen phosphate and compound fertilizer containing nitrogen, phosphorus, and potassium, respectively. The prepared chitosan was characterized by Fourier-transform infrared (FT-IR), differential scanning calorimetry (DSC), x-ray diffraction (XRD), and scanning electron microscopy (SEM), and its deacetylation degree and viscosity average molecular weight were 88.7% ± 0.68% and 792.1 ± 10.82 kDa, respectively. The recoveries of glutamic acid and isopropanol were 95.56% ± 1.39% and 88.14% ± 1.13%, respectively. The prepared chitosan has large molecular weight and deacetylation degree, controllable production cost, comprehensive utilization of crab shell components, and greatly reduced waste emissions.