RESUMO
CONTEXT: The Au-TiO2NPs have a wide range of applications and can easily enter the cells. Due to their properties, they can cause toxicity. OBJECTIVE: It was aimed to test the toxic effects of Au-TiO2 NPs in the brain, heart, kidney and liver of rats in this work. MATERIALS AND METHODS: All used rats in this work were treated using diverse concentrations (doses) of NPs (100 and 200 mg/kg bw) for 21 days. SOD, CAT, AChE activities and MDA, H2O2, NO contents were evaluated in different organs. RESULTS: The Au-TiO2 NPs exposure induced biochemical changes in different organs of rats in view of oxidative stress and neurotoxicity by the alteration of the activity of the enzyme of neurotransmitter (AChE activity). CONCLUSION: The Au-TiO2 NPs have the potential to interact with rat's biochemical status and cause undesirable effects. One of those damaging effects was oxidative stress and neurotoxicity. CLINICAL SIGNIFICANCE: The study signifies the impact of usage of Au-TiO2 NPs in the medical field for further exploration.
Assuntos
Encéfalo/efeitos dos fármacos , Ouro/toxicidade , Nanopartículas Metálicas/toxicidade , Síndromes Neurotóxicas/etiologia , Estresse Oxidativo/efeitos dos fármacos , Titânio/toxicidade , Animais , Biomarcadores/metabolismo , Encéfalo/metabolismo , Rim/efeitos dos fármacos , Rim/metabolismo , Rim/patologia , Fígado/efeitos dos fármacos , Fígado/metabolismo , Fígado/patologia , Masculino , Miócitos Cardíacos/efeitos dos fármacos , Miócitos Cardíacos/metabolismo , Miócitos Cardíacos/patologia , Síndromes Neurotóxicas/metabolismo , Síndromes Neurotóxicas/patologia , Ratos Wistar , Fatores de TempoRESUMO
In this work we evaluated the mode of action of six new synthesized peptides (Met-Asp-Asn; Glu-leu-Ala-Ala-Ala-Cys; Leu-Arg-Asp-Asp-Phe; Gly-Asn-Ala-Pro-Gly-Ala-Val-Ala; Ala-Leu-Arg-Met-Ser-Gly and Arg-Asp-Arg-Phe-Leu), previously identified, from the most active peptide fractions of RuBisCO peptic hydrolysate against Listeria innocua via a membrane damage mechanism. Antibacterial effect and the minimum inhibitory concentrations (MIC) of these peptides were evaluated against six strains and their hemolytic activities towards bovine erythrocytes were determined. Prediction of the secondary structure of peptides indicated that these new antibacterial peptides are characterized by a short peptide chains (3-8 amino acid) and a random coli structure. Moreover, it was observed that one key characteristic of antibacterial peptides is the presence of specific amino acids such as cysteine, glycine, arginine and aspartic acid. In addition the determination of the extracellular potassium concentration revealed that treatment with pure RuBisCO peptides could cause morphological changes of L. innocua and destruction of the cell integrity via irreversible membrane damage. The results could provide information for investigating the antibacterial model of antibacterial peptides derived from RuBisCO protein hydrolysates.
Assuntos
Antibacterianos/síntese química , Antibacterianos/farmacologia , Permeabilidade da Membrana Celular/efeitos dos fármacos , Membrana Celular/efeitos dos fármacos , Listeria/efeitos dos fármacos , Medicago sativa/química , Peptídeos/farmacologia , Hidrolisados de Proteína/metabolismo , Ribulose-Bifosfato Carboxilase/farmacologia , Sequência de Aminoácidos , Aminoácidos , Animais , Bovinos , Eritrócitos/efeitos dos fármacos , Glucose , Testes de Sensibilidade Microbiana , Modelos Moleculares , Fragmentos de Peptídeos/química , Fragmentos de Peptídeos/farmacologia , Peptídeos/síntese química , Conformação ProteicaRESUMO
In this study, the release of proteins and other biomolecules into an aqueous media from two red macroalgae (Sphaerococcus coronopifolius and Gelidium spinosum) was studied using eight different cell disruption techniques. The contents of carbohydrates, pigments, and phenolic compounds coextracted with proteins were quantified. In addition, morphological changes at the cellular level in response to the different pretreatment methods were observed by an optical microscope. Finally, the antioxidant capacity of obtained protein extracts was evaluated using three in vitro tests. For both S. coronopifolius and G. spinosum, ultrasonication for 60 min proved to be the most effective technique for protein extraction, yielding values of 3.46 ± 0.06 mg/g DW and 9.73 ± 0.41 mg/g DW, respectively. Furthermore, the highest total contents of phenolic compounds, flavonoids, and carbohydrates were also recorded with the same method. However, the highest pigment contents were found with ultrasonication for 15 min. Interestingly, relatively high antioxidant activities like radical scavenging activity (31.57-65.16%), reducing power (0.51-1.70, OD at 700 nm), and ferrous iron-chelating activity (28.76-61.37%) were exerted by the different protein extracts whatever the pretreatment method applied. This antioxidant potency could be attributed to the presence of polyphenolic compounds, pigments, and/or other bioactive substances in these extracts. Among all the used techniques, ultrasonication pretreatment for 60 min appears to be the most efficient method in terms of destroying the macroalgae cell wall and extracting the molecules of interest, especially proteins. The protein fractions derived from the two red macroalgae under these conditions were precipitated with ammonium sulfate, lyophilized, and their molecular weight distribution was determined using SDS-PAGE. Our results showed that the major protein bands were observed between 25 kDa and 60 kDa for S. coronopifolius and ranged from 20 kDa to 150 kDa for G. spinosum. These findings indicated that ultrasonication for 60 min could be sufficient to disrupt the algae cells for obtaining protein-rich extracts with promising biological properties, especially antioxidant activity.
RESUMO
Idiopathic pulmonary fibrosis is a chronic and progressive respiratory disease whose diagnosis and physiopathogenesis are still poorly understood and for which, until recently, there were no effective treatments. Over the past few decades, many studies have demonstrated that marine macroalgae such as red seaweeds are potential alternative sources of useful bioactive compounds possessing various physiological and biological activities. The present study was aimed to investigate the effect of Corallina officinalis aqueous extract (COAE) against bleomycin (BLM)-induced lung fibrosis in rat. Thus, Wistar rats were divided into 4 groups of 10 each: control, BLM (2 mg/kg), BLM/COAE-150 mg/kg and BLM/COAE-300 mg/kg once a day for 21 days. Obtained results showed that COAE is rich in phenolic compounds and exhibited relatively high antioxidant activity. COAE might significantly reduce the damage caused by BLM by rewarding the decline in weight and pulmonary index in rats given only BLM. Moreover, lungs, liver and kidneys lipid peroxidation, and sulfhydryl group levels were reversed significantly in a dose-dependent manner in the COAE-treated groups. BLM decreased superoxide dismutase (SOD) and catalase (CAT) activities, while COAE administration increased the antioxidant enzyme activities. Histopathologically, COAE attenuates the severity of the inflammatory lungs state caused by instillation of BLM in rats. These findings suggest that COAE can be a potential therapeutic candidate against BLM-induced lung fibrosis.
RESUMO
BACKGROUND: Marine snail (Hexaplex trunculus) presents increasing nutritional, commercial and economical importance, being widely consumed in northern Africa, particularly in Mediterranean countries. From a nutritional point of view there is still limited information on the chemical composition of edible tissues (meat and hepatopancreas) of this species. Therefore, the aims of the present work were to study the proximate chemical composition, fatty acid and amino acid profiles of H. trunculus from the Tunisian Mediterranean coasts. RESULTS: Fatty acid profiles showed that the polyunsaturated fatty acids (PUFA) content is higher than the saturated fatty acids (SFA). The yields of PUFA and SFA present in the meat fat were 68.2% and 33.4% of the total fatty acids, respectively. Similar values were obtained in the hepatopancreatic lipidic fraction. Snail tissues contain valuable concentrations of PUFA, especially n-6 and n-3 with chain lengths of 20 and 22 carbons. All edible tissues were valuable sources of essential amino acids. Aspartic acid is the major amino acids present in the meat and hepatopancreas. The concentrations of nutrients were also determined in the hepatopancreas and meat of H. trunculus. Significantly high concentrations of minerals and trace elements were found in these tissues. CONCLUSION: This study suggests that H. trunculus is an important source of protein and essential amino acids. Furthermore, the snail lipidic fraction contains high proportions of polyunsaturated fatty acids benefical for human health.
Assuntos
Aminoácidos Essenciais/análise , Gorduras na Dieta/análise , Proteínas Alimentares/análise , Ácidos Graxos/análise , Alimentos Marinhos/análise , Caramujos/química , Oligoelementos/análise , Animais , Ácido Aspártico/análise , Ecossistema , Humanos , Fígado/química , Região do Mediterrâneo , Minerais/análise , Valor Nutritivo , Pâncreas/química , TunísiaRESUMO
Antimicrobial peptides (AMPs) are extremely attractive candidates as therapeutic agents due to their wide spectrum of antimicrobial activity and mechanism of action, which differs from that of small-molecule antibiotics. In this study, a 6.0-kDa antimicrobial peptide from Aspergillus clavatus ES1, designated as AcAMP, was isolated by a one-step heat treatment. AcAMP was sensitive to proteolytic enzymes, stable between pH 5.0 and 10.0, and heat resistant (15 min at 100 degrees C). The acamp gene encoding AcAMP peptide was isolated by reverse-transcriptase polymerase chain reaction (RT-PCR) and cloned in pCRII-TOPO vector. Sequence analysis of the complementary DNA (cDNA) acamp gene revealed an open reading frame of 282 bp encoding a peptide of 94 amino acid residues consisting of a 21-aa signal peptide, a 22-aa pro-peptide, and a 51-aa mature peptide. The deduced amino acid sequence showed high identity with other ascomycete antifungal peptides. AcAMP belongs to the group of small, cysteine-rich, basic proteins with antimicrobial activity. In addition to its antifungal activity, AcAMP is the first fungal peptide exhibiting antibacterial activity against several Gram-positive and Gram-negative bacteria. Based on all these features, AcAMP can be considered as a promising new member of the restraint family of ascomycete antimicrobial peptides that might be used in biological control of plant diseases and also for potential applications in food preservation.
Assuntos
Peptídeos Catiônicos Antimicrobianos/química , Peptídeos Catiônicos Antimicrobianos/farmacologia , Aspergillus/química , Bactérias/efeitos dos fármacos , Proteínas Fúngicas/química , Proteínas Fúngicas/farmacologia , Fungos/efeitos dos fármacos , Sequência de Aminoácidos , Peptídeos Catiônicos Antimicrobianos/genética , Peptídeos Catiônicos Antimicrobianos/isolamento & purificação , Sequência de Bases , Clonagem Molecular , DNA Bacteriano/química , DNA Bacteriano/genética , DNA Complementar/genética , DNA Complementar/isolamento & purificação , Proteínas Fúngicas/genética , Proteínas Fúngicas/isolamento & purificação , Temperatura Alta , Concentração de Íons de Hidrogênio , Dados de Sequência Molecular , Peso Molecular , Fases de Leitura Aberta , Estabilidade Proteica , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Alinhamento de Sequência , Análise de Sequência de DNA , Homologia de Sequência de AminoácidosRESUMO
BACKGROUND: In Tunisia the cuttlefish-processing industry generates large amounts of solid wastes. These wastes, which may represent 35% of the original material and constitute an important source of proteins, are discarded without any attempt at recovery. This paper describes some functional properties and the angiotensin I-converting enzyme (ACE)-inhibitory activity of protein hydrolysates prepared by hydrolysis of cuttlefish (Sepia officinalis) by-products with crude enzyme extract from Bacillus licheniformis NH1. RESULTS: Cuttlefish by-product protein hydrolysates (CPHs) with different degrees of hydrolysis (DH 5, 10 and 13.5%) were prepared. All CPHs contained 750-790 g kg(-1) proteins. Solubility, emulsifying capacity and water-holding capacity increased while fat absorption and foaming capacity decreased with increasing DH. All hydrolysates showed greater fat absorption than the water-soluble fraction from undigested cuttlefish by-product proteins and casein. CPHs were also analysed for their ACE-inhibitory activity. CPH3 (DH 13.5%) displayed the highest ACE inhibition (79%), with an IC(50) value of 1 mg mL(-1). CONCLUSION: Hydrolysis of cuttlefish by-product proteins with alkaline proteases from B. licheniformis resulted in a product with excellent solubility over a wide pH range and high ACE-inhibitory activity. This study suggests that CPHs could be utilised to develop functional foods for prevention of hypertension.
Assuntos
Angiotensina I/antagonistas & inibidores , Inibidores da Enzima Conversora de Angiotensina/farmacologia , Decapodiformes , Proteínas de Peixes/metabolismo , Hidrolisados de Proteína/farmacologia , Inibidores da Enzima Conversora de Angiotensina/química , Animais , Bacillus/química , Proteínas de Bactérias/farmacologia , Endopeptidases/farmacologia , Gorduras/química , Manipulação de Alimentos , Hidrólise , Resíduos Industriais , Hidrolisados de Proteína/química , Coelhos , TunísiaRESUMO
Trypsin from the viscera of Bogue (Boops boops) was purified to homogeneity by precipitation with ammonium sulphate, Sephadex G-100 gel filtration and Mono Q-Sepharose anion exchange chromatography, with an 8.5-fold increase in specific activity and 36% recovery. The molecular weight of the purified enzyme was estimated to be 23 kDa by SDS-PAGE and size exclusion chromatography. The purified trypsin appeared as a single band on native-PAGE and zymography staining. The purified enzyme showed esterase-specific activity on N-α-benzoyl-L-arginine ethyl ester (BAEE) and amidase activity on N-α-benzoyl-DL-arginine-p-nitroanilide (BAPNA). The optimum pH and temperature for the enzyme activity, after 10 min incubation, were pH 9.0 and 55°C, respectively, using BAPNA as a substrate. The trypsin kinetic constants Km and kcat on BAPNA were 0.13 mM and 1.56 s(-1), respectively, while the catalytic efficiency kcat/Km was 12 s(-1) mM(-1). Biochemical characterisation of B. boops trypsin showed that this enzyme can be used as a possible biotechnological tool in the fish processing and food industries.
Assuntos
Perciformes/metabolismo , Tripsina/isolamento & purificação , Tripsina/metabolismo , Vísceras/enzimologia , Amidoidrolases/metabolismo , Animais , Aquicultura/métodos , Arginina/análogos & derivados , Benzoilarginina Nitroanilida , Cromatografia em Gel , Cromatografia por Troca Iônica , Dextranos , Esterases/metabolismo , Concentração de Íons de Hidrogênio , Cinética , Temperatura , Tripsina/químicaRESUMO
This study assesses the microplastics (MPs) levels in mussels (Mytilus galloprovincialis) and seawater from a southern Mediterranean lagoon (Bizerte lagoon, Northern Tunisia) and discusses the potential effects of its consumption on human health. Polyethylene was the most abundant in mussels and seawater, followed by polypropylene and cellophane. The lowest and highest average MPs concentrations were recorded in the lagoon channel and southern area of the lagoon, respectively, for both mussels (2.6 ± 1.7-12.0 ± 1.4 items mussel-1) and seawater (0.2 ± 0.1-0.7 ± 0.2 items L-1). Mussels in areas highly polluted with fibers and polyethylene were found to have higher potential to ingest and/or adhere higher numbers of these particles. The annual dietary intake of MPs by Tunisians through the consumption of local mussels was estimated at 4.2 items capita-1 year-1. Even though MPs are not biodegraded and can be excreted by humans, their potential human health risks are discussed in this paper.
Assuntos
Mytilus , Poluentes Químicos da Água/análise , Animais , Conservação dos Recursos Naturais , Monitoramento Ambiental , Humanos , Microplásticos , Plásticos , Alimentos Marinhos/análise , Água do Mar , TunísiaRESUMO
Compared to open sea environments, there is still limited knowledge about microplastic levels in semi-enclosed systems such as coastal lagoons. This work aims to assess the levels of MPs in the waters of an urban lagoon (Bizerte lagoon, northern Tunisia) and to study the effects of environmental factors on their distribution and abundance. Average concentration of total MPs was found to be 453.0 ± 335.2 items m-3. The upper 25 cm water layer of the lagoon is most likely to contain ~16.99 × 109 MPs items (which correspond to a total mass of 42.47 t). Fibers were the primary MPs types encountered, and most of MPs particles identified were white and clear-colored. Polyethylene and polypropylene were the predominant polymer types in Bizerte lagoon. Among the various potential plastic sources of MPs, unmanaged domestic plastic wastes are likely to be the major source of plastic pollution in the lagoon. Several environmental factors appeared to influence the distribution and density of MPs in the lagoon waters. These information contribute to better understand the dynamics of MPs in lagoons and to develop environmental management actions.
Assuntos
Plásticos , Poluentes Químicos da Água , Monitoramento Ambiental , Mar Mediterrâneo , Microplásticos , Tunísia , Poluentes Químicos da Água/análiseRESUMO
In modern societies, conscious consumers demand healthy, fresh and natural foods devoid of added chemical preservatives and stabilizers. The use of lactic acid bacteria (LAB) to preserve food is one of the oldest and best characterized approach. Production of organic acids is the main feature LAB use to outcompete spoilage organisms, but several other mechanisms have been demonstrated. In this review, a critical overview of the mechanisms used by LAB to inhibit spoilage organisms will be presented. Discrepancies between the concentrations of compounds resulting from LAB activity and their inhibitory amounts are discussed. Technical limitations hindering discoveries in this field as well as future trends in the application of LAB solutions to food bioprotection will be covered, including antifungal peptides and competitive exclusion.
Assuntos
Contaminação de Alimentos , Microbiologia de Alimentos , Fungos/metabolismo , Lactobacillales/metabolismo , Proteínas de Bactérias/metabolismoRESUMO
Sea cucumber fucoidan is recently endowed with a variety of biological activities. In the present study, we studied the structure and anticoagulant effect of fucoidan from the sea cucumber Holothuria polii (Fuc-Hp). The Fuc-Hp was purified by anion exchange chromatography and its structure was characterized by FT-IR and NMR spectroscopy. Molecular weight measurements were performed by HPSEC-MALLS-dRI. Fuc-Hp anticoagulant activity was measured by activated partial thromboplastin and thrombin times, and by in vitro thrombin inhibition in the presence of antithrombin and heparin cofactor II. The assessment of thrombin generation was investigated using calibrated automated thrombography. Fuc-Hp with a high sulfate content (34.6%) and an average molecular mass of 1376.3â¯kDa was isolated from H. polii in amount of ~2.7â¯mg/g dry body wall. Primary structural analysis indicated that Fuc-Hp was mainly composed of a tetrafucose repeating unit branched by glucuronic acid. Fuc-Hp exhibited a high anticoagulant effect mediated essentially by heparin cofactor II and to lesser extent by antithrombin with IC50 values of 0.16⯵g/mL and 0.5⯵g/mL, respectively. Overall results showed a high anticoagulant activity of Fuc-Hp, which was attributed to the high sulfate content and abundance of disulfated fucose residues of H. polii fucoidan.
Assuntos
Anticoagulantes/química , Anticoagulantes/farmacologia , Holothuria/química , Polissacarídeos/química , Polissacarídeos/farmacologia , Animais , Fenômenos Químicos , Humanos , Concentração Inibidora 50 , Peso MolecularRESUMO
Cinnamon bark and evergreen oak acorns, natural sources of functional ingredients, are effective for those suffering from diarrhea, constipation and irritable bowel syndrome. This study aimed to evaluate the dissimilar phytochemical composition and the opposite potential actions of Cinnamomum cassia bark (ACCE) and Quercus ilex aqueous extracts (GIAE) on gastrointestinal (GI)-physiological activities and disruptions. An HPLC-PDA/ESI-MS assay was used to identify the distinctive qualitative and quantitative profiles of phenolic compounds. The GI-physiological action of both extracts on gastric emptying (GE) and gastrointestinal transit time (GIT) were evaluated using the phenol-red colorimetric method and a test meal containing charcoal/gum arabic in water. Loperamide (LOP)-induced colonic constipation and delayed emptying of the stomach were used to explore the reverse effects of ACCE/GIAE on GI disorders. HPLC-PDA/ESI-MS showed that the main phenolic compounds detected in ACCE are trans-cinnamic acid, quinic acid, protocatechuic acid and rosmarinic acid, while gallic acid, quinic acid and protocatechuic acid are the major chemical constituents found in GIAE. GIAE at two doses (150 and 300 mg kg-1) exerted a reduction of GE (66.40% and 60.87%, respectively) compared to a control group (70.25%). However, ACCE at the same concentrations induced contradictory actions on GE/GIT in comparison to GIAE and antagonistic synthetic pharmacological drugs in rats. The protective effect of CCAE against constipation induced by LOP in rats was accompanied by a strong antioxidant property related to moderation of intracellular-mediator disorders. An absence of toxic actions was revealed in the case of the hematological profile and biochemical parameters. Hence, in-depth investigations of these nutrients of both extracts may help future researchers to derive the underlying mechanisms and potential molecular targets for the development of physiologically functional foods and future therapies.
RESUMO
Active food packaging films based on crab chitosan and Spirulina extract (SE) were developed. The effects of the SE incorporation at different levels on physical (color, opacity water vapor and oxygen permeability) and mechanical (tensile strength and elongation at break) properties of chitosan films were investigated. FTIR was carried out to observe the potential modifications of the chitosan films when incorporated with SE. The obtained results suggested that incorporation of SE into chitosan films improved mechanical and barrier properties. The antioxidant activity of the chitosan/SE films was characterized by means of three different analytical assays (DPPH, FRAP and FIC). Crab chitosan edible films containing SE showed higher antioxidant activity, regardless concentrations and methods assayed. Furthermore, the antioxidant activity occurred in a concentration-dependent manner. The agar disc diffusion method was used to determine the antibacterial activities of chitosan edible films against Escherichia coli, Staphylococcus aureus, Pseudomonas aeruginosa, Listeria monocytogenes, Salmonella typhimurium, Bacillus subtilis and Bacillus cereus. The chitosan/SE films were more effective (p<0.05) against five of the seven tested bacteria. The obtained crab chitosan edible films incorporated with SE showed great potential to be used for active food packaging due to its excellent antioxidant and antibacterial activities.
Assuntos
Braquiúros/química , Quitosana/química , Quitosana/farmacologia , Spirulina/química , Animais , Antibacterianos/química , Antibacterianos/farmacologia , Antioxidantes/química , Antioxidantes/farmacologia , Bactérias/efeitos dos fármacos , Cor , Embalagem de Alimentos , Fenômenos Mecânicos , Oxigênio/química , Permeabilidade , Fenóis/análise , VaporRESUMO
The fucosylated chondroitin sulfate (FuCS) was isolated from the sea cucumber Holothuria polii body wall and then purified by anion exchange chromatography and the structure was characterized by FT-IR and NMR spectroscopy. Anticoagulant activity was measured in plasma by classical anticoagulation tests and the thrombin generation was assessed by calibrated automated thrombography. The results showed that the FuCS obtained at a yield of 4.66% possesses high sulfate content 43% and an average molecular mass of 45.8kDa. Structural analysis revealed the presence of alternating units of chondroitine sulfate branched at position 3 of the ß-d-glucuronic acid by two types of fucose 2,4-O-di and 3,4-O-disulfated residues. The FuCS exhibited a high anticoagulant effect mediated essentially by heparin cofactor II and to lesser extent by antithrombin. Moreover, the CAT assay depicted a dual effect of FuCS with a procoagulant tendency for low doses and an anticoagulant effect at higher doses.
Assuntos
Anticoagulantes/farmacologia , Sulfatos de Condroitina/farmacologia , Coagulantes/farmacologia , Pepinos-do-Mar/química , Animais , Relação Dose-Resposta a Droga , Humanos , Agregação Plaquetária/efeitos dos fármacos , Espectroscopia de Infravermelho com Transformada de FourierRESUMO
Samples of Octopus vulgaris and Sepia officinalis were collected from four areas in the Gulf of Gabes, south-eastern Tunisia, and their edible tissues (mantle and arms) were analyzed for cadmium, copper, mercury, and zinc. While the concentrations of metals showed significant differences between the sampling sites, no differences were revealed between the tissues of the two species. The spatial distribution of metals analyzed showed similar pattern for both tissues of the two species, with the highest concentrations found in the central area of Gabes Gulf, and the lowest in the northern and/or southern areas. From a human health risk point of view, the highest values of estimated daily intake, target hazard quotient, and hazard index were found in the central area of Gabes Gulf. Although the results of these indices were, in general, not alarming, the health risks posed by the consumption of cephalopods on local consumers cannot be excluded.
Assuntos
Cádmio/metabolismo , Cefalópodes/metabolismo , Mercúrio/metabolismo , Animais , Cádmio/análise , Cobre/análise , Cobre/metabolismo , Monitoramento Ambiental , Contaminação de Alimentos , Humanos , Mercúrio/análise , Medição de Risco , Tunísia , Poluentes Químicos da Água/análise , Poluentes Químicos da Água/metabolismo , Zinco/análise , Zinco/metabolismoRESUMO
Within the framework of a study on the extent and history of marine pollution in the central area of Gabes Gulf, the concentrations of four trace metals (Cd, Cu, Pb, and Zn) were assessed in three different tissues of the seagrass species, Posidonia oceanica (leaves, rhizomes, and roots), in the mat of P. oceanica meadows at different depths from the sea floor (- 30 to - 150 cm) and in sediments. The results showed that P. oceanica leaves accumulate more Cd, Cu, and Zn, whereas Pb was found to be more concentrated in roots. The analysis of P. oceanica mat highlighted a clear decreasing gradient of trace metal concentrations from lower (- 30 cm) to higher (- 150 cm) depths. Considering that P. oceanica mat continuously rises above the initial level, with a rate of 1 m per century (~1 cm year-1; Molinier and Picard Ann Inst Océanogr Fr 27:157-234, 1952), the latter observation suggested that the pollution level in Gabes Gulf increased continuously during the last few decades. The results of the P. oceanica mapping in the study area showed a continuous regression of its meadows as well as its local disappearance from various areas in the central part of Gabes Gulf. The current status of P. oceanica is most likely due to the cumulative effects of the discharges from the coastal industrial complex of Gabes-Ghannouche represented mainly by the phosphogypsum discharges. This study confirms the usefulness of P. oceanica not only as a bioindicator of the "health status" of coastal ecosystems but also as a record register tracing back the history and temporal evolution of coastal contamination level.
Assuntos
Alismatales/química , Biomarcadores Ambientais , Monitoramento Ambiental/métodos , Metais Pesados/análise , Água do Mar/química , Poluentes Químicos da Água/análise , Alismatales/crescimento & desenvolvimento , Biomassa , Sulfato de Cálcio/análise , Ecossistema , Fósforo/análise , Folhas de Planta/química , Folhas de Planta/crescimento & desenvolvimento , TunísiaRESUMO
Emulsions are widely used in food and pharmaceutical applications for the encapsulation, solubilization, entrapment, and controlled delivery of active ingredients. In order to fulfill the increasing demand for clean label excipients, natural polymers could be used to replace the potentially irritative synthetic surfactants used in emulsion formulation. In the present study, we have studied the properties of oil-in-water emulsions prepared with land snail gelatin (LSG) as the sole emulsifying agent, extracted and described for the first time. LSG was evaluated in terms of proximate composition, oil and water holding capacity, emulsifying and foaming properties, color and amino acid composition. Emulsions of trioctanoylglycerol (TC8) and olive oil were made at different gelatin/oil ratios and changes in droplet-size distribution were determined. The superior emulsifying properties of LSG, the susceptibility of gelatin protein emulsions increasing flocculation on storage, and the coalescence of gelatin emulsions following centrifugation were demonstrated. Furthermore, the effect of LSG on the activity of turkey pancreatic lipase (TPL) was evaluated through the pH-stat methodology with TC8 and olive oil emulsions. The LSG affected the TPL activity in a concentration-dependent way. Our results showed that LSG, comparably to gum arabic, increases the pancreatic lipase activity and improves its stability at the oil-water interface.
Assuntos
Emulsificantes/química , Gelatina/química , Caracois Helix/química , Lipase/antagonistas & inibidores , Lipase/metabolismo , Animais , Emulsões/química , Azeite de Oliva/química , Azeite de Oliva/metabolismo , Pâncreas/enzimologia , Espectroscopia de Infravermelho com Transformada de Fourier , Perus/metabolismoRESUMO
Chitin was recovered through enzymatic deproteinization of the Norway lobster (Nephrops norvegicus) processing by-products. The obtained chitin was characterized and converted into chitosan by N-deacetylation, the acid-soluble form of chitin. Chitosan samples were then characterized by Fourier transform infrared spectroscopy (FTIR) and 13 Cross polarization magic angle spinning nuclear magnetic resonance (CP/MAS)-NMR spectroscopy. The antimicrobial activity and anti-proliferative capacity of chitosan were evaluated. Antimicrobial activity assays indicated that prepared chitosan exhibited marked inhibitory activity against the bacterial and fungal strains tested. Further, cytotoxic effects of chitosan samples on human colon carcinoma cells HCT116 was evaluated using the MTT assay. Chitosan showed the antiproliferative capacity against the colon-cancer-cell HCT116 in a dose dependent manner with IC50 of 4.6mg/ml. Indeed, HCT116 cell proliferation was significantly inhibited (p<0.05) between 13.5 and 67.5% at 0.5-6mg/mL of chitosan after 24h of cell treatment. The chitosan showed high antitumor activity which seemed to be dependent on its characteristics such as acetylation degree.
Assuntos
Antibacterianos/farmacologia , Antineoplásicos/farmacologia , Quitina/farmacologia , Quitosana/farmacologia , Decápodes/química , Resíduos Industriais , Acetilação , Animais , Antibacterianos/química , Antineoplásicos/química , Antineoplásicos/isolamento & purificação , Bactérias/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Quitina/química , Quitina/isolamento & purificação , Quitosana/química , Quitosana/isolamento & purificação , Células HCT116 , HumanosRESUMO
Sulfated glycosaminoglycans (SGNL) were extracted for the first time from Norway lobster (Nephrops norvegicus) shell. The monosaccharide composition analysed by GC/MS revealed the presence of galacturonic acid, glucuronic acid, N-acetylgalactosamine and N-acetylglucosamine. The analysis of SGNL with acetate cellulose electrophoresis in Zn-acetate revealed the presence of heparan sulfate (HS) and dermatan sulfate (DS). SGNL were evaluated for their anticoagulant activities using activated partial thromboplastin time (aPTT), thrombin time (TT) and prothrombine time (PT) tests. After 21h incubation, HCT116 cell proliferation was inhibited (p<0.05) between 39.7 and 54.8% at 1.5-7.5mg/mL of SGNL. SGNL don't show hemolytic activity towards bovine erythrocytes and no cytotoxicity against the normal lymphocytes. The antiproliferative efficacy of these lobster glycosaminoglycans were probably related with the higher sulfate content. SGNL demonstrated promising antiproliferative and anticoagulant potential, which may be used as a novel, effective and promising antithrombotic agent.