家贮海贝三法

贻贝、蛤仔、毛蚶、杂色蛤等是我国北方沿海地区最常见的贝类。这几种贝类,肉质细嫩,味道鲜美,营养丰富,是受大众欢迎的海产品。海贝上市季节性强,不易贮存,一般只有在旺季才能吃到鲜品。人们通常也是吃多少买多少,很少自己贮存。为了使您能常年吃到这些海中美味,下面介绍3种适宜家庭加工贮存海贝的方法。     

壳里,内容着营养

贝,是个象形字,甲骨文和金文字形似海贝。谈到吃的,那就是海产及河产的有贝壳的软体动物的统称。四大名菜中(蜗牛与鱼翅、干贝、鲍鱼)贝类占了三个,可见是美味。在公元前21世纪时,贝壳就因为外形美丽,有一定的流通价值,开始作为货币使用了,并且一直延续到公元2世纪的商周时期。可知我们伟大的祖先很早就对贝类进行了开发利用。古代的流水没有重金属铜、汞、铅的污染,     

海洋细菌产低温碱性蛋酶菌株的筛选研究

采集连云港黄海海域的各类海鱼和贝类及海水等样品，采用富集培养、干酪素培养基及水解酪蛋白试验分离产蛋白酶的菌株。结果表明从海鱼、海贝等样品中能得到产低温碱性蛋白酶的菌株；干酪素分离培养基是较好的筛选培养基，产酶菌株都能在干酪素培养基上产生透明圈；水解酪蛋白试验可对菌株的产酶情况进行定性研究，酶活较高的菌株都能产生较大的水解圈。干酪素分离培养基配合水解酪蛋白试验进行产低温碱性蛋白酶菌株的筛选，可以提高筛选效率。     

麻痹性贝类毒素监测指示贝种的筛选研究

为了解深圳地区贝类麻痹性贝类毒素(paralytic shellfish poison,PSP)染毒情况,对深圳地区主要贝类养殖海域养殖的10种贝类麻痹性贝类毒素染毒情况进行调查。筛选并确定PSP监测指示贝种,进而测定不同养殖海区PSP污染情况。采用AOAC发布的生物法测定麻痹性贝类毒素含量。华贵栉孔扇贝(Chalmys nobilis)和翡翠贻贝(Perna viridis)对PSP蓄积能力强,华贵栉孔扇贝的PSP含量较翡翠贻贝高。确定深圳贝类养殖海域PSP监测指示贝种为华贵栉孔扇贝和翡翠贻贝,全年对两种贝类的PSP监测结果表明PSP含量超过有关标准规定的安全限量的情况时有发生。本研究为实施有效的监测预警管理制度提供了科学依据。     

2018—2020年河北省市售贝类中麻痹性贝类毒素污染状况调查分析

目的了解2018—2020年河北省市售贝类中麻痹性贝类毒素(paralytic shellfish poison,PSP)污染状况。方法 2018年8月—2020年5月间,对河北省市售的7种双壳贝类,共508份进行检测分析。样品经0.5%乙酸水提取,石墨化碳黑固相萃取柱净化,采用高效液相色谱-串联质谱法进行检测。结果 508份样品,PSP阳性样品24份,检出率为4.7%, 15份样品超过世界卫生组织规定安全限量,超标率为3.0%。检出贝类为贻贝、毛蚶、杂色蛤、扇贝, PSP含量范围分别为217.0~13001.8μg石房蛤毒素当量(saxitoxin equivalent, STXeq/kg)、217.0~4893.2μg STXeq/kg、217.0~503.6μg STXeq/kg、217.0~11024.5μg STXeq/kg;超标贝类为贻贝、毛蚶、扇贝。贝类中检出的PSP类型有GTX1、GTX4、GTX2、GTX3、neoSTX、STX。结论河北省市售贝类麻痹性贝类毒素暴露风险整体较低,秦皇岛地区贻贝等贝类产品在4、5月份较易受到PSP污染,应持续关注,加强早期监测预警。     

深圳市海域麻痹性贝类毒素时空分析

目的掌握广东省深圳市海域麻痹性贝类毒素时空分布特征,确定重点污染海域,为实现早期预警提供科学依据。方法通过对2015年深圳市海域3个监测点(斜吓湾、东涌和珍珠岛)的麻痹性贝类毒素含量监测数据进行径向基函数插值分析和时空扫描分析,掌握监测点周围的麻痹性贝类毒素含量的大体分布状况和时空聚集区域。结果由径向基函数插值结果可知,斜吓湾海域麻痹性贝类毒素含量相对较高,东涌和珍珠岛海域含量相对较低,而且斜吓湾、东涌和珍珠岛海域的麻痹性贝类毒素含量分布特点存在明显差异;时空扫描发现麻痹性贝类毒素在时间和空间上存在明显聚集性。2015年1~6月斜吓湾海域是最可能聚集海域(LLR=7.72,RR=5.59,P=0.000 830.001)。结论通过径向基函数插值和时空扫描分析方法可以获得麻痹性贝类毒素空间分布规律以及时空聚集特征。     

一起麻痹性贝类毒素引起的食源性疾病暴发事件调查

目的分析一起因麻痹性贝类毒素中毒引起的食源性疾病暴发事件发生原因及流行病学特征,总结调查处置经验,为指导预防控制工作提供依据。方法回顾该起事件调查处置过程,进行流行病学特征分析和防控效果评价。结果本次事件是由于海域发生赤潮导致贝类食品染毒,中毒病例164名,50岁以上人群占病例总数的57.9%(95/164),主要临床表现为唇舌肢端麻木(100.0%,164/164)、乏力(75.0%,123/164),患者最短潜伏期为10 min,最长潜伏期为24 h,平均潜伏期为3 h,可疑致病食物为淡菜、海蛎等贝类食品,在10份食物样品中有8份检出麻痹性贝类毒素。采取综合性防控措施后,事件得到控制。结论相关部门应加大赤潮危害宣传力度,扩大赤潮监视监测范围,及时发布危害预警,减少贝类毒素中毒风险。     

我国海洋贝类资源的利用现状和发展趋势

本文对我国海洋贝类资源概况,海洋贝类资源在传统加工食品、功能性食品、医药等其他领域的利用现状进行了综述,并针对我国在海洋贝类资源利用中存在的问题,从贝类养殖、贝类加工技术设备、贝类深加工和综合利用、贝类食品风险控制等方面,提出了发展我国贝类产业的四个措施。     

省市联合攻关 科技创出佳绩

近日,由南通市卫生监督所、江苏省卫生监督所、南通市海洋渔业局等单位共同完成的“海产贝类食品安全示范工程及污染预警研究”项目，荣获南通市科技进步一等奖。这是最近五年以来，预防医学领域的研究成果在南通市科技进步奖励表彰中所取得的最好成绩，也是南通市医疗卫生单位在2008年度市级科技进步表彰中所获得的最高奖项。     

贝类毒素控制措施及组合的研究

本文简要介绍了麻痹性贝类毒素、腹泻性贝类毒素、神经性贝类毒素及健忘性贝类毒素等贝类毒素的来源、性质、组成及中毒机理, 探讨了企业贝类毒素控制措施组合并初步探讨了企业HACCP管理体系的建立。     

基于温控近红外光谱快速检测泥蚶重金属污染

目的:探索一种基于蛋白酶解、温控近红外光谱表征技术的贝类重金属污染快速检测方法。方法:以人工饲养的贝类泥蚶为研究对象,以铜（Cu）、镉（Cd）、铅（Pb）三种重金属分别胁迫感染泥蚶;利用酶解和离心等预处理分别提取健康泥蚶和各重金属污染泥蚶的全蛋白上清液样品;控制样品处于一个25~60 ℃的升温过程中,以傅里叶变换近红外光谱,每间隔5 ℃采集各样品光谱,并构建判别模型对泥蚶污染样本进行区分。结果:通过偏最小二乘-判别模型识别不同温度下的泥蚶重金属污染类别,其准确率随温度先升高后降低;当样品升温至40 ℃时,判别模型的准确率达到92%;通过变量筛选优化,能够将判别模型的准确率提高至98%。结论:借助化学计量学、近红外光谱技术和酶解技术,可以快速鉴别泥蚶中的重金属污染问题,丰富贝类重金属污染的检测手段。     

RT-PCR法检测贝类中的甲肝病毒的研究

在世界范围内,甲肝病毒是与食用贝类有关的主要传染性疾病之一。由于贝类中含有PCR抑制剂以及病毒富集过程中病毒的回收率低,阻碍了天然污染的贝类中HAV的PCR检测。研究中建立了一种经苷氨酸缓冲液洗涤,2次PEG沉降富集病毒,然后进行RNA提取和RT-PCR对贝类中的甲肝病毒进行检测的方法。经比较,采用小体系肠道样品检测比采用全贝检测的富集效果更佳,并比较了PEG8000和PEG6000对病毒富集的效果,回收率分别为13.5%和7.6%,此方法可有效地降低PCR抑制剂的影响,最低检测限可达10个TCID50/1.5 g。     

Microbiological Quality of Finfish and Shellfish with Special Reference to Shiga Toxin-Producing Escherichia coli O157

ABSTRACT:  The objective of this study was to determine the microbiological quality of fish and shellfish from Kolkata, India, with special emphasis on E. coli O157. Fresh and ice-preserved Labeo rohita , Catla catla , Cirrhinus mrigala , Oreochromis mossambica , Heteropneustes fossilis , Clarias batrachus , and Penaeus monodon were examined for total heterotrophic bacteria and coliform loads and presence of E. coli and E. coli serotype O157 by culture method. While the total plate count of bacteria was within acceptable or marginally acceptable limits for most samples, fishes were contaminated with coliforms, including E. coli , indicating poor hygiene and sanitary conditions. Although E. coli O157 could not be detected, a few samples were contaminated with non-O157 serotypes of enterohaemolysin- and Shiga toxin-producing E. coli , raising public health concern.     

Contamination of shellfish from Shanghai seafood markets with paralytic shellfish poisoning and diarrhetic shellfish poisoning toxins determined by mouse bioassay and HPLC

This paper reports the results of investigations of shellfish toxin contamination of products obtained from Shanghai seafood markets. From May to October 2003, 66 samples were collected from several major seafood markets. Paralytic shellfish poisoning (PSP) and diarrhetic shellfish poisoning (DSP) toxins in shellfish samples were monitored primarily by a mouse bioassay, then analysed by HPLC for the chemical contents of the toxins. According to the mouse bioassay, eight samples were detected to be contaminated by PSP toxins and seven samples were contaminated by DSP toxins. Subsequent HPLC analysis indicated that the concentrations of the PSP toxins ranged from 0.2 to 1.9 µg/100 g tissues and the main components were gonyautoxins 2/3 (GTX2/3). As for DSP, okadaic acid was detected in three samples, and its concentration ranged from 3.2 to 17.5 µg/100 g tissues. Beside okadaic acid, its analogues, dinophysistoxins (DTX1), were found in one sample. According to the results, gastropod (Neverita didyma) and scallop (Argopecten irradians) were more likely contaminated with PSP and DSP toxins, and most of the contaminated samples were collected from Tongchuan and Fuxi markets. In addition, the contaminated samples were always found in May, June and July. Therefore, consumers should be cautious about eating the potential toxic shellfish during this specific period.     

水产品中麻痹性贝类毒素（PSTs）检测技术的研究进展

麻痹性贝类毒素是一种分布范围广及危害较大的赤潮毒素。可经食物链的富集、传递作用,引发人体麻痹性中毒,大量发生的中毒事件,对人类健康和经济构成了严重威胁。目前,麻痹性贝类毒素常用检测技术主要是小鼠生物法、高效液相色谱法和酶联免疫试剂盒测试法,这些检测方法均有各自的优势,但麻痹性贝类毒素成分多且复杂、结构特殊,毒性又较强,这使得其监管检测较为困难,亟待建立快速简便、灵敏度高、特异性强的分析检测方法。本文基于麻痹性贝类毒素的基本性质,依据检测原理的不同论述了其生物检测技术、仪器分析技术和生化测试技术,并对各类技术的特点进行分析,提出建设性的意见,最后展望了未来麻痹性贝类毒素检测技术的发展趋势,以期为麻痹性贝类毒素检测监管提供借鉴。     

Investigation of diarrhetic shellfish toxins in Lingshan Bay,Yellow Sea,China, using solid-phase adsorption toxin tracking (SPATT)

Early detection of toxin contamination in shellfish (i.e., prior to harvest) would be of considerable advantage to fish farmers, researchers and food safety administrators. In 2004, a solid-phase adsorption toxin tracking (SPATT) technique was developed to study algal toxins in New Zealand shellfish harvesting areas. In subsequent years, the basic idea have been further developed. Using a SPATT method, an investigation into diarrhetic shellfish toxins (DSTs) was conducted over a 10.5-month period in 2012 in shellfish farming areas in Lingshan Bay (Yellow Sea, China). This paper discusses the relationship among DSTs in toxic algae, seawater and contaminated shellfish. OA, DTX1 and PTX2 toxins were found in this shellfish farming area from summer to autumn. In shellfish the maximum concentrations of OA and DTX1 were 81 and 41 ng g^–1 respectively. PTX2 was very low. The maximum levels of OA and DTX1 in seawater were 165 and 56 ng g^–1 respectively, and were detected on June, separated by a 14-day period. Shellfish had accumulated the highest levels of OA and DTX1 recorded in this study. Comparison of the variations in DST levels in seawater showed there to be about 2 weeks for administrators to warn of the potential for toxin contamination in shellfish. Further research to explore the relationship between the variables of seawater temperature, sunlight and salinity, and DSTs in shellfish may help to establish a more suitable model for forecasting DST contamination in shellfish.     

Cooking mussels (Mytilus galloprovincialis) by steam does not destroy the infectivity of Cryptosporidium parvum

The consumption of shellfish has increased considerably worldwide, with an associated increase in foodborne illnesses. Among the bivalves, the mussels are usually cooked by steam, which constitutes a typical dish in several regions. In this article, we demonstrate that this preparation is not sufficient to destroy completely the infectivity of Cryptosporidium parvum. Oocysts recovered from experimentally contaminated mussels (Mytilus galloprovincialis) were infectious to neonatal mice after cooking. Although, to date, no official cases of cryptosporidiosis linked to shellfish consumption have been reported, we recommend that people with reduced immunity avoid this type of food because they are at high risk of being infected with Cryptosporidium spp. after eating raw or undercooked contaminated bivalves.     

Do saxitoxin-like substances have a role in scombrotoxicosis?

Evidence is presented which establishes that mackerel fed in captivity can, by relay from contaminated shellfish via sand eels, accumulate paralytic shellfish poisons (PSP) in the edible flesh at a level (250 micrograms saxitoxin equivalents per kg) similar to that in the contaminated shellfish. Data from ELISAs performed independently in two laboratories show that commercial mackerel fillets which have been associated with incidents of scombrotoxicosis contained 0.02-1.30 micrograms saxitoxin equivalents per kg, concentrations some two to four orders of magnitude below that normally detectable by the mouse bioassay. The doses, expressed as saxitoxin equivalents, administered inadvertently during volunteer testing of such fillets ranged up to 0.5 ng/kg bw, at least four orders of magnitude less than the fatal oral dose for an adult. The doses associated with the rapid induction of nausea/vomiting and/or diarrhoea, 0.11-1.0 ng/kg bw, could not be distinguished from the doses which failed to produce such symptoms in susceptible volunteers (up to 0.5 ng/kg bw). Factors that might explain this lack of correlation between dose (saxitoxin equivalents) and volunteer response are discussed along with previously published reports of PSP relay through the food web. It is suggested that the relay of algal toxins, particularly PSP, but possibly in combination with diarrheic shellfish poisons, may be responsible for scombrotoxicosis.     

Azaspiracid poisoning, the food-borne illness associated with shellfish consumption

Azaspiracid poisoning (AZP) is a recently discovered toxic syndrome that was identified following severe gastrointestinal illness from the consumption of contaminated mussels (Mytilus edulis). The implicated toxins, azaspiracids, are polyethers with unprecedented structural features. Studies toward total toxin synthesis revealed that the initial published structures were incorrect and they have now been revised. These toxins accumulate in bivalve molluscs that feed on toxic microalgae of the genus Protoperidinium, previously considered to be toxicologically benign. Although first identified in shellfish from Ireland, azaspiracid contamination of several types of bivalve shellfish species has now been confirmed throughout the western coastline of Europe. Toxicological studies have indicated that azaspiracids can induce widespread organ damage in mice and that they are probably more dangerous than previously known classes of shellfish toxins. The exclusive reliance on live animal bioassays to monitor azaspiracids in shellfish failed to prevent human intoxications. This was a consequence of poor sensitivity of the assay and the fact that azaspiracids are not exclusively found in the shellfish digestive glands used for toxin testing. The strict regulatory control of azaspiracids in shellfish now requires frequent testing of shellfish using highly specific and sensitive methods involving liquid chromatography-mass spectrometry.     

Keeping shellfish safe to eat: a brief review of shellfish toxins,and methods for their detection

Poisoning can result from the ingestion of shellfish contaminated with phycotoxins. Various types of poisoning may occur, each of which is caused by a toxin (or group of toxins) from a particular alga. Classically, the mouse bioassay has been used to detect shellfish toxins, but there is pressure, both ethical and regulatory, to move away from this. A number of techniques have been developed to replace the bioassay, including immunoassay, chromatography, pharmacological assay and tissue-culture tests. All have advantages and limitations. These methods and their potential are reviewed.