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1.
Chemosphere ; 239: 124767, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31518925

RESUMO

The present study analyzed the Peruvian scallop Argopecten purpuratus and its food sources for metal and fatty acid concentrations in order to determine spatial and temporal differences. Metals such as copper (Cu), manganese (Mn), and zinc (Zn) in gills and iron (Fe) and Zn in sediments were the most significant explaining factors for spatial differentiations (degree of contamination), while for fatty acids, it was C14:0, C15:0, C16:0 and C18:0 in A. purpuratus' muscle and in its food sources, which explained more temporal differences (El Niño-Southern Oscillation (ENSO) effect). Gills, digestive gland and intestine were the tissues where metal accumulation was the highest in A. purpuratus. Cd in digestive gland was always high, up to ∼250-fold higher than in other tissues, as previously reported in other bioindicator species for metal pollution. Fatty acids were good biomarkers when annual comparisons were performed, while metals when locations were compared. ENSO 2017 played an important role to disentangle A. purpuratus' biological conditions and food sources. A. purpuratus from Paracas locations mostly showed higher metal concentrations in gills and digestive glands, and lower fatty acid concentrations in muscle than those from Sechura and Illescas Reserved Zone.


Assuntos
Monitoramento Ambiental/métodos , Sedimentos Geológicos/análise , Pectinidae/química , Poluentes Químicos da Água/análise , Animais , Aquicultura , Cobre/análise , Cobre/farmacocinética , Biomarcadores Ambientais , Ácidos Graxos/análise , Brânquias/química , Ferro/análise , Ferro/farmacocinética , Manganês/análise , Manganês/farmacocinética , Músculos/química , Pectinidae/metabolismo , Peru , Frutos do Mar/análise , Análise Espaço-Temporal , Distribuição Tecidual , Zinco/análise , Zinco/farmacocinética
2.
Toxins (Basel) ; 10(12)2018 11 23.
Artigo em Inglês | MEDLINE | ID: mdl-30477142

RESUMO

Causative species of Harmful Algal Bloom (HAB) and toxins in commercially exploited molluscan shellfish species are monitored weekly from four classified shellfish production areas in Perú (three in the north and one in the south). Okadaic acid (OA) and pectenotoxins (PTXs) were detected in hand-picked cells of Dinophysis (D. acuminata-complex and D. caudata) and in scallops (Argopecten purpuratus), the most important commercial bivalve species in Perú. LC-MS analyses revealed two different toxin profiles associated with species of the D. acuminata-complex: (a) one with OA (0.3⁻8.0 pg cell-1) and PTX2 (1.5⁻11.1 pg cell-1) and (b) another with only PTX2 which included populations with different toxin cell quota (9.3⁻9.6 pg cell-1 and 5.8⁻9.2 pg cell-1). Toxin results suggest the likely presence of two morphotypes of the D. acuminata-complex in the north, and only one of them in the south. Likewise, shellfish toxin analyses revealed the presence of PTX2 in all samples (10.3⁻34.8 µg kg-1), but OA (7.7⁻15.2 µg kg-1) only in the northern samples. Toxin levels were below the regulatory limits established for diarrhetic shellfish poisoning (DSP) and PTXs (160 µg OA kg-1) in Perú, in all samples analyzed. This is the first report confirming the presence of OA and PTX in Dinophysis cells and in shellfish from Peruvian coastal waters.


Assuntos
Dinoflagellida/citologia , Furanos/análise , Toxinas Marinhas/análise , Ácido Okadáico/análise , Pectinidae/química , Piranos/análise , Animais , Monitoramento Ambiental , Contaminação de Alimentos/análise , Macrolídeos , Peru
3.
Peptides ; 32(9): 1909-16, 2011 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-21787820

RESUMO

Antimicrobial peptides (AMP) have been widely described in several organisms from different kingdoms. We recently designed and evaluated a synthetic version of an AMP isolated and characterized from Argopecten purpuratus hemocytes. This study describes the generation of a chimaeric gene encoding for Ap-S, the use of this construct to transform E. coli strain BL21, and the evaluation of the purified recombinant Ap-S (rApS) as an antifungal agent. The proposed gene coding for rAp-S consists of 93 nucleotides arranged downstream from the IPTG-inducible T7 promoter. The best synthesis conditions were obtained after E. coli cultivation at 26°C for 3h, which allowed for the production of an rAp-S-enriched fraction containing the peptide at 249µM. Mass spectrometry analysis of the purified rAp-S (3085.80Da) showed the addition of a glycine residue on its N-terminal end derived from vector design and peptide purification. The purified rApS fraction was assayed for antifungal activity by direct addition of purified rApS elution to potato dextrose agar media at a final concentration of 81nM. These assays showed important growth inhibitions of both biotrophic (Fusarium oxysporum, Trichoderma harzianum) and necrotrophic (Botrytis cinerea, Alternaria spp.) fungi in that the hyphae structures and spore count were affected in all cases. The strategy of cloning and expressing rAp-S in E. coli, the high yield obtained and its successful use for controlling pathogenic fungi suggest that this molecule could be applied to agricultural crops using various management strategies.


Assuntos
Antifúngicos/farmacologia , Escherichia coli/metabolismo , Pectinidae/química , Peptídeos/farmacologia , Alternaria/efeitos dos fármacos , Sequência de Aminoácidos , Animais , Antifúngicos/isolamento & purificação , Sequência de Bases , Botrytis/efeitos dos fármacos , Clonagem Molecular , Contagem de Colônia Microbiana , Escherichia coli/genética , Escherichia coli/crescimento & desenvolvimento , Fusarium/efeitos dos fármacos , Genes Sintéticos , Vetores Genéticos , Testes de Sensibilidade Microbiana , Dados de Sequência Molecular , Peptídeos/isolamento & purificação , Peptídeos/metabolismo , Proteínas Recombinantes/biossíntese , Proteínas Recombinantes/isolamento & purificação , Proteínas Recombinantes/farmacologia , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz , Trichoderma/efeitos dos fármacos
4.
Braz J Biol ; 70(3): 651-8, 2010 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-20730354

RESUMO

This work describes the gametogenic cycle of the scallop Nodipecten nodosus kept in a culture system. To this end, during one year, samples were taken from the broodstocks every 30 days to be submitted to macroscopic and microscopic analyses and to measure the amount of astaxanthin. To perform the microscopic evaluation, 5 micro slices from the median portion of the female part of the gonad were submitted to the pattern methodology for histological analyses with paraffin and HE coloration. The remaining portion of the female gonad was lyophilised to extract and quantify the levels of astaxanthin using HPLC. The microscopic analyses revealed four well defined stages for the reproductive cycle. Analyses of data taken throughout the year indicated preferential spawning periods from December to January and from July to September. The astaxanthin analyses showed higher amounts of this carotenoid during the advanced pre-spawning and the initial spawning periods than during gametogenesis, initial pre-spawning, advanced spawning, and the spent stages. According to these results, it was possible to establish a descriptive table of the sexual stages of the female portion of the gonad and the amount of astaxanthin in the sexual stage of the scallop Nodipecten nodosus.


Assuntos
Gônadas/química , Pectinidae/fisiologia , Maturidade Sexual/fisiologia , Animais , Cromatografia Líquida de Alta Pressão , Feminino , Gônadas/anatomia & histologia , Gônadas/crescimento & desenvolvimento , Pectinidae/anatomia & histologia , Pectinidae/química , Reprodução/fisiologia , Xantofilas/análise
5.
Braz. j. biol ; 70(3): 651-658, Aug. 2010. tab, ilus
Artigo em Inglês | LILACS | ID: lil-555279

RESUMO

This work describes the gametogenic cycle of the scallop Nodipecten nodosus kept in a culture system. To this end, during one year, samples were taken from the broodstocks every 30 days to be submitted to macroscopic and microscopic analyses and to measure the amount of astaxanthin. To perform the microscopic evaluation, 5 μ slices from the median portion of the female part of the gonad were submitted to the pattern methodology for histological analyses with paraffin and HE coloration. The remaining portion of the female gonad was lyophilised to extract and quantify the levels of astaxanthin using HPLC. The microscopic analyses revealed four well defined stages for the reproductive cycle. Analyses of data taken throughout the year indicated preferential spawning periods from December to January and from July to September. The astaxanthin analyses showed higher amounts of this carotenoid during the advanced pre-spawning and the initial spawning periods than during gametogenesis, initial pre-spawning, advanced spawning, and the spent stages. According to these results, it was possible to establish a descriptive table of the sexual stages of the female portion of the gonad and the amount of astaxanthin in the sexual stage of the scallop Nodipecten nodosus.


Este trabalho descreve o ciclo gametogênico da vieira Nodipecten nodosus mantida em ambiente de cultivo. Para isto, durante um ano, amostras de indivíduos reprodutores foram coletadas a cada 30 dias e submetidas à avaliação macroscópica e microscópica e à quantificação de astaxantina. Para a avaliação microscópica, secções de 5 μ da porção mediana feminina da gônada foram submetidas à metodologia de análise histológica padrão em parafina e coloração HE. O restante da porção feminina da gônada foi liofilizado para extração e quantificação de astaxantina em HPLC. A avaliação microscópica permitiu a descrição de quatro estágios bem definidos para o ciclo reprodutivo. Na análise ao longo do ano, foram observados períodos preferenciais de desova em dezembro e janeiro e de julho a setembro. A análise da quantidade de astaxantina, mostrou, nos estádios de pré-desova avançada e de desova inicial, uma maior quantidade desse carotenoide em comparação aos estádios de gametogênese, pré-desova inicial, desova avançada e repouso. Em função desses resultados, foi possível estabelecer um quadro descritivo dos estágios sexuais da porção feminina da gônada e quantidade de astaxantina em cada estágio sexual da vieira Nodipecten nodosus.


Assuntos
Animais , Feminino , Gônadas/química , Pectinidae/fisiologia , Maturidade Sexual/fisiologia , Cromatografia Líquida de Alta Pressão , Gônadas/anatomia & histologia , Gônadas/crescimento & desenvolvimento , Pectinidae/anatomia & histologia , Pectinidae/química , Reprodução/fisiologia , Xantofilas/análise
6.
Toxicon ; 55(4): 692-701, 2010 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-19852974

RESUMO

Azaspiracids are a family of lipophilic polyether marine biotoxins that have caused a number of human intoxication incidents in Europe since 1995 following the consumption by consumers of intoxicated shellfish (Mytilus edulis). These azaspiracids have now been identified in mussels (Mytilus chilensis) and scallops (Argopecten purpuratus) from two Chilean locations. This is the first report of the occurrence of azaspiracid toxins in these species (Mytilus chilensis and Argopecten purpuratus) from Chile. The areas studied were Bahía Inglesa (III Region, 27 degrees SL) and Chiloé Archipelago, both important scallop and mussels farming areas. Separation of azaspiracid (AZA1), azaspiracid isomer (AZA6) and its analogues, 8-methylazaspiracid (AZA2) and 22-demethylazaspiracid (AZA3), was achieved using reversed-phase LC and toxins were identified using a turbo electrospray ionisation (ESI) source, to a triple quadrupole mass spectrometer. In mussels, AZA1 was the predominant toxin in mussel hepatopancreas with AZA2, AZA3 and AZA6 present in approximate equivalent amounts in the remaining tissues, 20-30% of the AZA1 level. AZA2 predominated in the scallop samples with the toxin almost entirely present in the hepatopancreas (digestive gland). AZA1 was only observed in some of the scallop samples and was present at 12-15% of the AZA2 levels. Whilst the levels of AZAs in Chilean samples are below the EU regulatory limit of 160mug/kg, it is significant that this toxin is present in Pacific Ocean species. Consequently measures should be taken by regulatory authorities to implement regular seafood monitoring to ensure safety of harvested product.


Assuntos
Bivalves/química , Toxinas Marinhas/isolamento & purificação , Pectinidae/química , Compostos de Espiro/isolamento & purificação , Animais , Chile , Toxinas Marinhas/química , Espectrometria de Massas por Ionização por Electrospray , Compostos de Espiro/química
7.
Braz J Biol ; 69(1): 209-15, 2009 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-19347167

RESUMO

In marine bivalve mollusks, unsaturated molecules called carotenoids are present in the natural diet and play an important role in different biological process, especially in reproduction. In order to gain more insights into these compounds in Nodipecten nodosus it was necessary to develop a suitable protocol for extraction of carotenoids from the gonads. Female gonads of cultured scallops (75 mm length) were lyophilized and macerated in liquid N2. To verify the effect of composition in organosolvents on the extracting solutions, two organic solvents were tested: acetone and hexane (Ac = O:Hex) at four ratios, 1:1, 1:3, 1:5, and 2:3, in four static extraction times: 0, 5, 10, and 15 minutes. Total carotenoids and astaxanthin contents were determined in the crude extracts by UV-visible spectrophotometry and high performance liquid chromatography (HPLC), respectively. Triplicate aliquots of 50 mg were used for each treatment. The results indicated that the best single extraction (0.312 +/- 0.016 microg carotenoids/mg) was attained with Ac = O: Hex 1:3, for 15 minutes. Through exhaustive extraction methodology (10x), a superior yield (0.41 +/- 0.001 microg carotenoids/mg) was obtained from a gonad sample in comparison to the highest value found for a single extraction. Astaxanthin content was reduced by 8.6% in carotenoid extract preservation assay, i.e., -18 degrees C, 26 days incubation, under N2 atmosphere.


Assuntos
Carotenoides/isolamento & purificação , Gônadas/química , Pectinidae/química , Animais , Cromatografia Líquida de Alta Pressão , Feminino , Espectrofotometria Ultravioleta , Xantofilas/isolamento & purificação
8.
Braz. j. biol ; 69(1): 209-215, Feb. 2009. graf, tab
Artigo em Inglês | LILACS | ID: lil-510144

RESUMO

In marine bivalve mollusks, unsaturated molecules called carotenoids are present in the natural diet and play an important role in different biological process, especially in reproduction. In order to gain more insights into these compounds in Nodipecten nodosus it was necessary to develop a suitable protocol for extraction of carotenoids from the gonads. Female gonads of cultured scallops (75 mm length) were lyophilized and macerated in liquid N2. To verify the effect of composition in organosolvents on the extracting solutions, two organic solvents were tested: acetone and hexane (Ac = O:Hex) at four ratios, 1:1, 1:3, 1:5, and 2:3, in four static extraction times: 0, 5, 10, and 15 minutes. Total carotenoids and astaxanthin contents were determined in the crude extracts by UV-visible spectrophotometry and high performance liquid chromatography (HPLC), respectively. Triplicate aliquots of 50 mg were used for each treatment. The results indicated that the best single extraction (0.312 ± 0.016 µg carotenoids/mg) was attained with Ac = O: Hex 1:3, for 15 minutes. Through exhaustive extraction methodology (10x), a superior yield (0.41 ± 0.001 µg carotenoids/mg) was obtained from a gonad sample in comparison to the highest value found for a single extraction. Astaxanthin content was reduced by 8.6 percent in carotenoid extract preservation assay, i.e., -18 °C, 26 days incubation, under N2 atmosphere.


Em moluscos bivalves marinhos, carotenóides insaturados estão presentes na dieta natural, com um importante papel em diversos processos biológicos, em especial na reprodução. A elucidação dos efeitos destes compostos em Nodipecten nodosus requer o desenvolvimento de um protocolo adequado para a extração de carotenóides das gônadas desses animais. Para isso, gônadas de vieiras cultivadas (75 mm de comprimento) foram liofilizadas e maceradas em N2 líquido. Amostras em triplicata com 50 mg foram coletadas para a utilização em cada tratamento. Os conteúdos de carotenóides totais e astaxantina foram determinados via espectrofotometria de luz UV-visível e cromatografia líquida de alta eficiência (CLAE), respectivamente. O efeito da composição em organosolventes das soluções de extração foi testado utilizando-se acetona (Ac = O) e hexano (Hex) em quatro proporções (Ac = O:Hex): 1:1, 1:3, 1:5, e 2:3; em quatro tempos de extração: 0, 5, 10, e 15 minutos. Os resultados mostraram que o melhor rendimento de extração (0,312 ± 0,016 µg carotenóides/mg) foi obtido com Ac = O:Hex, 1:3, por 15 minutos. Com a utilização de protocolo de extração exaustiva (10x), uma quantidade superior (0,41 ± 0,001 µg de carotenóides/mg) foi obtida de amostras de gônada, comparativamente aos valores obtidos em extrações únicas. O conteúdo de astaxantina foi reduzido em 8,6 por cento em testes de preservação deste metabólito em extratos crus (-18 °C, 26 dias de incubação em atmosfera de N2).


Assuntos
Animais , Feminino , Carotenoides/isolamento & purificação , Gônadas/química , Pectinidae/química , Cromatografia Líquida de Alta Pressão , Espectrofotometria Ultravioleta , Xantofilas/isolamento & purificação
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