虾夷扇贝毒素yessotoxins(YTXs),中国沿海贝类中首次发现的一组贝类生物毒素

采用高效液相色谱-串联质谱方法对我国近海贝类中腹泻性贝毒成分进行研究,结果发现采自北黄海大连附近海域的海湾扇贝和虾夷扇贝含有25~41μg/kg的虾夷扇贝毒素(yessotoxin,YTX),在虾夷扇贝体内还含有37.2μg/kg的45-OH-YTX,并在5种贝中发现微量的Homo-YTX毒素组分,这是首次报道在我国贝中检出此类毒素。虾夷扇贝毒素YTXs是一类含有2个磺酰基的脂溶性多环聚醚类化合物,对小鼠的腹腔注射急性致死毒性很高,毒理作用机制尚不清楚。本研究的结果说明我国贝类体内生物毒素成分复杂,亟需进行毒素成分结构、来源生物、生态毒理效应、分布规律及安全限定标准的研究。     

浙南海域腹泻性贝毒分析

在浙南海域共采集了10种贝类40份样品.运用高效液相色谱方法检测腹泻性贝毒,共检出 9份样品含有腹泻性贝毒.染毒样品检出的腹泻性贝毒(软海绵酸,OA)质量比为0.07～5.85 μg/g,共有7个样品含量超标,超标率为17.5%.无论是检出率还是超标率,都呈现夏季>春季>秋季的规律.浙南海域的南部腹泻性贝毒检出率和超标...     

浙江近岸海域贝类中重金属和贝毒污染状况研究

在浙江近岸海域采集了青蛤(Cyclina sinensis)、毛蚶(Scapharca subcrenata)、厚壳贻贝(Mytilus coruscus)、缢蛏(Sinonovacula constricta)、泥螺(Bullacta exarata)、菲律宾蛤仔(Ruditapes philippi-narum)、文蛤(Meretrix meretrix)、僧帽牡蛎(Ostrea cucullata)和栉孔扇贝(Chlamys farreri)共9种贝类计29份样品,检测其中重金属汞、砷、铜、铅、锌、镉以及麻痹性贝毒和腹泻性贝毒.结果表明,瑞安毛蚶、瑞安栉孔扇贝中有麻痹性贝类毒素检出,嵊泗文蛤、毛蚶和乐清牡蛎中存在重金属超标的情况;牡蛎对汞、铜、锌、镉有较强的富集能力.     

秦皇岛近岸海域脂溶性藻毒素污染状况与来源分析

2016年以来,秦皇岛地区多次出现麻痹性贝类毒素导致的中毒事件,但对于该海域脂溶性藻毒素的污染状况仍不够了解。2020—2021年,本研究通过对秦皇岛近岸海域为期1年的现场采样调查,应用高效液相色谱-质谱联用手段检测了浓缩浮游植物和贻贝(Mytilus galloprovincialis)、牡蛎(Crassostrea gigas)和扇贝(Chlamys farreri)3种贝类中脂溶性藻毒素的污染状况,并通过高通量测序手段对浮游植物样品中的潜在有毒藻种进行了分析。结果表明,在秦皇岛近海浮游植物样品和贝类中均可检出扇贝毒素-2(pectenotoxin-2,PTX2),其中2021年4—5月浓缩浮游植物样品中的PTX2毒素含量达到最高值1.36ng/L,贝类中的PTX2毒素也主要在该时段检出,4月26日3种贝类中均可检出PTX2,含量最高达到1.10μg/kg。对浮游植物样品的高通量测序结果表明,样品中检测到的鳍藻序列数与毒素含量具有显著线性相关性,推测PTX2毒素主要来自样品中的渐尖鳍藻(Dinophysis accuminata)和倒卵形鳍藻(D.fortii)等。综合一年的调查结...     

江苏沿海贝类软体中麻痹性贝毒素种类及含量变化的多年观测研究

Paralytic shellfish toxins(PSTs) are notorious neurotoxins that threaten public health and food safety worldwide.Although PST monitoring programs have recently been established throughout China, the profiles and variation of PSTs in important commercial clams(e.g., Mactra veneriformis, Ruditapes philippinarum, and Meretrix meretrix) along the Jiangsu Province coastline remain largely unexplored. In this study, a validated hydrophilic interaction liquid chromatography–tandem mass spectrometry(HILIC-MS/MS) method was used to examine PST profiles and levels in 540 clam samples from natural production areas along Jiangsu Province coastline during2014–2016. Although the PST levels(≤6.38 μg saxitotoxin equivalents(eq)/kg) were consistently below European Union regulatory limits(≤800 μg saxitotoxin eq/kg) during this time period, saxitotoxin, decarbamoylsaxitotoxin,and gonyautoxins 1 and 4 were detected, and nearly 40% of the samples were saxitotoxin-positive. The PST levels also varied significantly by seasons, with peak values observed in May during 2014–2016. This is the first systematic report of PSTs in clams from Jiangsu Province, and additional research and protective measures are needed to ensure the safety of clams harvested in this area.     

Spawning strategies and transport of early stages of the two Cape hake species,Merluccius paradoxus and M. capensis,in the southern Benguela upwelling system

Seasonal and short-term variability of environmental parameters influence the spawning strategies of fish species. In this study, the spawning strategies and the transport of early stages of the two Cape hake species off South Africa were investigated. Distribution of eggs and larvae of Merluccius paradoxus and M. capensis was analysed in order to derive more detailed and species-specific information on spawning season, spawning location, and transport of early stages. Samples were collected during three pilot surveys between January and October 2007 and during an extensive survey in September/October 2008 in the southern Benguela upwelling system off South Africa. Eggs and larvae of M. paradoxus were found in greater numbers than those of M. capensis during all surveys. Highest abundances were found from September to October, indicating one spawning peak for M. paradoxus during late austral winter to spring. The western Agulhas Bank was identified as the primary spawning ground, and smaller spawning events occurred on the West Coast. Larvae of both species were mainly distributed in subsurface waters between 25 and 100 m. More than 50% of all larvae caught had a total length between 3 and 4 mm and size increased significantly with decreasing latitude. Merluccius capensis were found closer inshore than M. paradoxus, indicating that early stages of the two species followed separate drift routes. We assume that this distribution pattern most likely evolved from differences in spawning location and phenology. The spawning strategies of M. paradoxus and M. capensis are well adapted to a time-frame of optimal transport conditions favourable for larval survival in the highly variable environment of the southern Benguela upwelling system, but the peak spawning of the two species is separated in time and space.     

花生四烯酸调控网络在贻贝麻痹性贝毒代谢中的作用基于转录组和代谢组联合分析

紫贻贝（Mytilus galloprovincialis）是富集麻痹性贝类毒素（Paralytic Shellfish Toxins, PSTs）能力很强的代表性双壳贝类,但研究表明紫贻贝暴露于PSTs也会引起机体炎症反应,其作用机理及对毒素代谢影响尚不清楚。本研究采用转录组学与代谢组学联合分析技术,比较了产PSTs的链状亚历山大藻（Alexandrium catenella）暴发的不同时期,紫贻贝机体的基因表达量与代谢物含量差异,以解析PSTs胁迫下紫贻贝机体的炎症反应机制。结果表明,紫贻贝暴露于PSTs后表达的基因和代谢物均发生显著变化,其中差异表达基因17232个,差异代谢物341个。基于联合分析,差异表达基因与差异代谢物显著富集在花生四烯酸和谷胱甘肽代谢通路中,基因PLA2G2F、ALOX5、TBXAS1以及代谢物ARA、PGH₂、TXA₂、LTA₄、5-HETE对贻贝机体的促炎反应发挥重要作用;而基因GPX4、CYP2J2和代谢物15-HETE、GSH则调节机体炎症的消退。本研究揭示花生四烯酸相关通路在贻贝机体炎症反应过程中具有重要的调控作用,为下一步深度揭示PSTs胁迫下贻贝机体炎症网络化响应机制提供了研究基础。