Tải bản đầy đủ - 0 (trang)
To feed or not to feed? Artificial feeding affects coral reef fish functions (Aitutaki, Cook Islands), Natalie Prinz [et al.]

To feed or not to feed? Artificial feeding affects coral reef fish functions (Aitutaki, Cook Islands), Natalie Prinz [et al.]

Tải bản đầy đủ - 0trang

H3/ Ciguatera fish poisoning in the

Indo-Pacific region



480



Applicability of the fluorescent Receptor

Binding Assay (RBAf ) to the detection of

Ciguatoxins in Pacific reef fish.

Taiana Darius ∗† 1 , Taina Revel 1 , J´erˆome Viallon 1 , Jennifer Mccall 2 ,

Ransom Hardison 3 , William Holland 3 , Patricia Tester 4 , Wayne Litaker

3

, Mireille Chinain 1

1



2



3



Institut Louis Malard´e - UMR 241 EIO, Laboratoire des Micro-algues Toxiques – PO Box 30, 98713

Papeete, Tahiti, French Polynesia

Center for Marine Science, University of North Carolina at Wilmington, – 5600 Marvin K. Moss Lane,

Wilmington, North Carolina 28409 USA, United States

National Oceanic Atmospheric Administration, National Center for Coastal Ocean Science, Center for

Coastal Fisheries and Habitat Research (CCFHR) (CCFHR (NOAA)) – 101 Pivers Island Road,

Beaufort, NC 28516, USA, United States

4

Ocean Tester, LLC – 381 Gillikin Road, Beaufort, North Carolina 28516, United States



Seafood is a source of both basic nutrition and significant income for many communities in

the Pacific region. Unfortunately, many cases of Ciguatera fish poisoning (CFP) occur every year

after eating seafood, including fishes but also marine invertebrates, that have bio-accumulated

lipid-soluble ciguatoxins (CTXs) produced by microalgae in the genus Gambierdiscus. Some of

the challenges for CTX detection and analysis in seafood are low concentrations (µg/kg) of toxin

present that are sufficient to pose a health threat to consumers, toxin integration in complex

fish tissue matrix, and the diversity of potential CTX congeners found within a single sample.

The fluorescent Receptor Binding Assay (RBAf) is known for its ability to detect brevetoxin

standards as well as Pacific CTXs (P-CTX-3C) and was recently applied to detect CTXs in

Caribbean fishes.

The aim of this study was to evaluate the applicability of the RBAf to detect P-CTXs in

several in vitro cultures of Gambierdiscus samples as well as in herbivorous and carnivorous

fishes collected in different islands of French Polynesia. In addition to the cooking step which is

required prior to the extraction step to avoid potential interference of native fluorescence in fish

samples with signal to noise ratios of the RBAf, the advantage of a freeze-drying pretreatment

was also tested. As fish can represent an extremely complex sample matrix, the impacts of two

different chemical extraction protocols and matrix effects have also been explored. Quantification of P-CTXs in Gambierdiscus and fishes samples by RBAf were similar with toxicity data

obtained using the radioactive RBA (RBAr) and/or the Cell Based Assay on neuroblastoma

(CBA-N2a).

These first results highlights the potential usefulness of the RBAf as a monitoring tool to detect

P-CTXs in contaminated algae and Pacific reef fish for Pacific Island Countries and Territories

communities known to be highly affected by CFP.







Speaker

Corresponding author: tdarius@ilm.pf



481



Application of Solid Phase Adsorption

Toxin Tracking (SPATT) devices for an

improved Ciguatera Fish Poisoning (CFP)

risk assessment

M´elanie Rou´e 1 , H´el`ene Taiana Darius ∗ 2 , J´erˆome Viallon 2 , Andr´e Ung

2

, Cl´emence Gatti 2 , D. Tim Harwood 3 , Mireille Chinain 2

1



Institut de Recherche pour le D´eveloppement (UMR 241 EIO) (IRD) – PO Box 529, 98713 Papeete Tahiti, French Polynesia

2

Institut Louis Malard´e, Laboratory of Toxic Microalgae (UMR 241 EIO) (ILM) – PO Box 30, 98713

Papeete - Tahiti, French Polynesia

3

Cawthron Institute – Private Bag 2, Nelson, 7010, New Zealand



Ciguatera fish poisoning (CFP) is a food-borne illness caused by the consumption of tropical coral reef fish contaminated with ciguatoxins (CTXs), polyether neurotoxins produced by

dinoflagellates in the Gambierdiscus genus. Toxic fish appear in perfect freshness, furthermore,

CTXs are odorless, tasteless and generally undetectable by any simple chemical test, making it

very difficult for consumers to determine if a fish is safe for consumption or not. Since most

surveillance programs currently rely on the survey of Gambierdiscus cell densities and species

composition, supplementary toxin-based methods allowing the time- and spatially integrated

sampling of toxins in ciguateric environments are needed for a more reliable assessment and

management of the risks associated with Gambierdiscus proliferation, and to better help local

populations to manage CFP risk. Solid Phase Adsorption Toxin Tracking (SPATT) technology use porous synthetic resins capable of adsorbing toxins directly from the water column.

The present study aimed at evaluating the ability of these passive monitoring devices to retain

Gambierdiscus toxins. Field trials involving the deployment of SPATT filters were conducted

in two French Polynesian locations at high (Nuku Hiva) vs. low to moderate (Kaukura) risk

of ciguatera. CTXs could be detected in SPATT bags extracts from Nuku Hiva, as assessed

by the mouse neuroblastoma cell-based assay (CBA-N2a) and liquid chromatography - tandem

mass spectrometry analyses (LC-MS/MS). Furthermore, despite the non detection of maitotoxin

(MTX), LC-MS/MS analyses showed that two other compounds also produced by Gambierdiscus species were retained on SPATT bags, i.e. iso-P-CTX-3B/C and a putative MTX analogue,

named MTX-3. This study, the first to demonstrate the suitability of SPATT technology for

the in situ monitoring of Gambierdiscus toxins, highlights the potential application of this tool

for routine ciguatera risk assessment and management programs.







Speaker



482



Ciguatera fish poisoning in the South

Pacific: implementation of a regional

surveillance network (CIGUA-WATCH

PROJECT)

Cl´emence Gatti

1



3



∗† 1



, Nicolas Ponzo 2 , Bruno Jouvin 3 , Mireille Chinain



1



Institut Louis Malard´e (ILM) – BP30, Papeete 98713, Tahiti, French Polynesia

2

Geonesia – BP 380 462, 98718 Tamanu, Tahiti, French Polynesia

Pae Tae Pae Uta (PTPU) – BP 1746, 98713, Papeete, Tahiti, French Polynesia



Ciguatera Fish Poisoning (CFP), considered the most prevalent ichtyosarchotoxism related

to the consumption of reef fish, represents a major threat for South Pacific populations, given

their high dependence on marine resources.

The gap of knowledge on the ecophysiology of Gambierdiscus responsible for ciguatoxins (CTXs)

production and the lack of a rapid/inexpensive field-detection test, along with the constant evolution of ciguatoxic areas, represent a major obstacle for risk assessment, health prevention and

local economy sustainability.

Since 2007, French Polynesia has implemented a CFP epidemiological surveillance network,

relying on reports by public health medical staff on each CFP case seen in consultation in medical structures. This surveillance program is co-managed by Institut Louis Malard´e, a local

research institution, and the Public Health Directorate of French Polynesia.

For 10 years, data were collected on paper forms, manually filled in, transmitted by fax or

postal mail and stored on a local database. Since 2015, an online CFP declaration system was

developed in order to improve and facilitate CFP declaration among medical professionals and

general public. This online tool is related to an online database and a real-time CFP risk map,

available online in free access 24/24h. This map allows following the evolution of poisoning

events, by providing information about date, areas and fish product responsible for human poisoning.

To date, very few countries dispose of a CFP monitoring system and are not able to quantify CFP events or clearly identify toxic species and areas.

The aim of CIGUA-WATCH project is to develop and adapt the existing surveillance tools

implemented in French Polynesia for use by New Caledonia, Cook Islands and Wallis & Futuna

authorities.

In fine, CIGUA-WATCH aspires at building a common database, for improved standardization







Speaker

Corresponding author: mahanaitigatti@gmail.com



483



Tài liệu bạn tìm kiếm đã sẵn sàng tải về

To feed or not to feed? Artificial feeding affects coral reef fish functions (Aitutaki, Cook Islands), Natalie Prinz [et al.]

Tải bản đầy đủ ngay(0 tr)

×