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1.
Sci Total Environ ; 774: 145043, 2021 Jun 20.
Artigo em Inglês | MEDLINE | ID: mdl-33609843

RESUMO

In recent years, high resolution mass spectrometry (HRMS) combined with separation techniques has allowed comprehensive analysis of contaminants of emerging concern (CECs) as well as their metabolites and transformation products in various environmental samples via retrospective screening. However, to date, only a few suspect or non-targeted studies on the occurrence of CECs in marine aquatic system are reported. In this study, two methods, based on direct injection for seawater, or ultrasound-assisted extraction for sediments, followed by LC-Q-TOF-MS analysis were developed and applied for the simultaneous targeted and screening of contaminants in coastal samples (seawater, particulates and sediment) from Qatar collected in 2017-2018. Among the twenty-one target analytes (pesticides, PPCPs and a plasticizer), two compounds only were detected in seawater. Caffeine was detected in seawater samples at all sampling sites, and cotinine was detected in seawater samples collected in Umm Bab in 2018 and seawaters receiving stormwater. Traces of trimethoprim and carbamazepine were detected in sediment samples collected at four sites in 2017. These results suggest some inputs of domestic wastewater in the coastal waters in Qatar. In total, twelve molecular features were tentatively identified from suspect screening at concentration levels significantly higher than that in procedure blanks. The presence of four plasticizers and one pesticide were further confirmed using reference standards: diethyl phthalate (DEP), dibutyl phthalate (DBP), and tributyl phosphate (TBP) in seawater samples; bis(2-ethylhexyl) phthalate (DEHP) in sediment and particulate samples; and dinoterb in seawater after storm event and particulate samples. Overall, this study demonstrated the potential of high resolution LC-Q-TOF-MS/MS for combined targeted and non-targeted analyses of trace contaminants in marine systems over a broad range of log P values.


Assuntos
Monitoramento Ambiental , Poluentes Químicos da Água , Catar , Estudos Retrospectivos , Água do Mar , Espectrometria de Massas em Tandem , Água , Poluentes Químicos da Água/análise
2.
PLoS One ; 15(5): e0232205, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32401792

RESUMO

This study presents the taxonomic description of two new sponge species that are intimately associated with the hyperarid mangrove ecosystem of Qatar. The study includes a preliminary evaluation of the sponges' potential bioactivity against pathogens. Chalinula qatari sp. nov. is a fragile thinly encrusting sponge with a vivid maroon colour in life, often with oscular chimneys and commonly recorded on pneumatophores in the intertidal and shallow subtidal zone. Suberites luna sp. nov. is a massive globular-lobate sponge with a greenish-black colour externally and a yellowish orange colour internally, recorded on pneumatophores in the shallow subtidal zone, with large specimens near the seagrass ecosystem that surrounds the mangrove. For both species, a drug extraction protocol and an antibacterial experiment was performed. The extract of Suberites luna sp. nov. was found to be bioactive against recognized pathogens such as Staphylococcus epidermidis, Staphylococcus aureus and Enterococcus faecalis, but no bioactive activity was recorded for Chalinula qatari sp. nov. This study highlights the importance of increasing bioprospecting effort in hyperarid conditions and the importance of combining bioprospecting with taxonomic studies for the identification of novel marine drugs.


Assuntos
Antibacterianos , Ecossistema , Poríferos/classificação , Animais , Secas , Catar
3.
Mar Genomics ; 51: 100734, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-31818705

RESUMO

The pearl oyster Pinctada imbricata radiata is an iconic species in Qatar, representing an integral part of the nation's cultural heritage and one of the main economic foundations upon which the nation developed. During the early part of the 20th century, nearly half the Qatar population was involved in the pearl oyster industry. However, the fishery has undergone steady decline since the 1930s, and the species is now under threat due to multiple confounding pressures. This manuscript presents the first de novo transcriptome of the Qatari pearl oyster assembled into 30,739 non-redundant coding sequences and with a BUSCO completeness score of 98.4%. Analysis of the transcriptome reveals the close evolutionary distance to the conspecific animal Pinctada imbricata fucata but also highlights differences in immune genes and the presence of distinctive transposon families, suggesting recent adaptive divergence. This data is made available for all to utilise in future studies on the species.


Assuntos
Pinctada/genética , Transcriptoma , Animais , Catar
4.
PLoS One ; 14(5): e0215865, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31042736

RESUMO

A number of molluscs within the Class Bivalvia are defined by their ability to secrete fine silk like threads known as byssus which are used to anchor themselves to solid substrates. With relatively few exceptions the majority of these species remain in a sedentary state throughout their life attached via their byssal threads. However, observations of adult Pinctada imbricata radiata pearl oysters made during this study revealed this species' ability to implement active movement. Byssal threads were secreted in a sequence of attachment and detachment phases, which resulted in the active displacement of the oyster. The oyster was observed, in the laboratory over a 9 day period, travelling a distance of 28cm in a horizontal path. After horizontal displacement, a vertical climbing phase was observed until the oyster reached the water surface at which point the byssus was discarded and the animal dropped, drifting in accordance with water current intensity. It is possible that these adaptations of byssal use are a result of environmentally induced evolutionary change within P. i. radiata.


Assuntos
Pinctada/fisiologia , Seda/fisiologia , Animais , Oceano Índico , Locomoção
5.
Zootaxa ; 4250(4): 389-395, 2017 Apr 06.
Artigo em Inglês | MEDLINE | ID: mdl-28610015

RESUMO

The Indo-West Pacific genus Coleusia Galil 2006, was recently described and now comprises seven species. We describe a new species from the western Arabian Gulf, Coleusia janani n. sp. The new species is closely related to the congener C. biannulata (Tyndale-Biscoe & George, 1962), and can be distinguished from other species at these genus congeners mainly by the straight upward apical shape of the male first pleopod (G1). An updated identification key to the species of Coleusia, as well as an overview of the geographical distribution of the species included in the genus are also presented.


Assuntos
Braquiúros , Distribuição Animal , Estruturas Animais , Animais , Masculino
6.
Zootaxa ; 4107(3): 353-66, 2016 May 03.
Artigo em Inglês | MEDLINE | ID: mdl-27394825

RESUMO

Genetic analysis divides Panulirus argus into two different species, physically separated by the Amazon-Orinoco plume since the Last Glacial Maximum. Panulirus argus sensu stricto is distributed north of this biogeographic barrier and the second species to the south, occurring in Brazil. The Panulirus species in the Atlantic Ocean are being overfished and the standing stocks are unknown and still not considered endangered or threatened due to a deficiency of precise abundance data. The lack of data makes it impossible to undertake an effective conservation and management policy. In order to assist in the future management and conservation of the Spiny Lobster in the Atlantic Ocean and particularly for the indigenous species from Brazilian waters, this study formally recognizes and describes a new species, Panulirus meripurpuratus sp. nov., for what was previously known as P. argus in Brazilian waters, and differentiates it from Panulirus argus from North American waters and the Caribbean Sea. The work also presents an overview of the biogeographic distribution of the species and presents two identification keys to Atlantic species, one based on morphology and the other on live colouration.


Assuntos
Distribuição Animal , Palinuridae/anatomia & histologia , Palinuridae/classificação , Animais , Oceano Atlântico , Brasil , Feminino , Masculino , Palinuridae/genética , Palinuridae/fisiologia , Especificidade da Espécie
7.
Zootaxa ; 3972(3): 419-31, 2015 Jun 12.
Artigo em Inglês | MEDLINE | ID: mdl-26249501

RESUMO

In subtidal zones, certain shrimp species with cryptic behaviour represent a gap in the biodiversity description in many places in the world. This study extends the southern limit of Stenopus hispidus (Oliver, 1811), Alpheus formosus Gibbes, 1850, Alpheus cf. packardii Kingsley, 1880 and Lysmata ankeri Rhyne & Lin, 2006 to Santa Catarina State-Brazil, 27oS. The results also confirm the new occurrence of Stenopus spinosus Risso, 1827 in Brazilian waters. All specimens were collected by scuba diving from rocky islands between 3 and 25 meters depth. We present for each species certain taxonomic features in colour images that will help to identify these decapods in situ in further monitoring programs.


Assuntos
Decápodes/classificação , Distribuição Animal , Estruturas Animais/anatomia & histologia , Estruturas Animais/crescimento & desenvolvimento , Animais , Oceano Atlântico , Tamanho Corporal , Brasil , Decápodes/anatomia & histologia , Decápodes/crescimento & desenvolvimento , Ecossistema , Feminino , Masculino , Tamanho do Órgão
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