一种检测濑尿虾中镉残留的直接ELISA

为了快速而简单地检测镉残留,以镉特异性单克隆抗体与酶标抗原为基础,构建了一种直接竞争的酶联免疫吸附测定方法.该方法的检测下限为0.2 μg/L,IC50为3.01 μg/L,其他金属螯合物的交叉反应均低于1.6 %,检测的变异系数为6.67 %~9.09 %.该方法石墨炉原子吸收光谱法的检测结果的相关系数为0.988.结果表明,所构建的直接竞争的酶联免疫吸附测定方法能快速而又准确地测定濑尿虾中镉残留的含量.     

流沙湾海水养殖珍珠微观结构及形成机制研究

利用扫描电子显微镜(SEM)、原子力显微镜(AFM),研究流沙湾海水珍珠珍珠质层和棱柱层的微尺度生长结构,采用傅里叶变换红外光谱仪(FTIR)对珍珠质层及棱柱层的成分组成进行分析.结果表明:构成海水珍珠珍珠层的珍珠质层,棱柱层和过渡层的微结构和组成是有所不同的,珍珠质层主要为文石型碳酸钙,纳米文石微晶颗粒与有机质颗粒交织形成文石板片,棱柱层中存在方解石和文石两种晶型的碳酸钙,过渡层是由有机质和少量的碳酸钙共同组成;通过对珍珠层结构和成分的研究,初步推断出其生长模式分三个阶段:(1)珠母贝从海水环境中富集钙离子,并分泌有机质诱导碳酸钙成核结晶,二者共同生长形成棱柱层;(2)棱柱层生长到一定阶段,晶体生长的同时珠母贝分泌的有机质发生变化形成一层有机质过渡层,调控碳酸钙的生长;(3)在有机质层上初始成核的纳米文石微晶颗粒与有机质颗粒交织堆砌生长,形成文石板片,文石板片层层堆叠形成结构致密排列有序的珍珠质层.     

<Emphasis Type="Italic">Desmoscaris tripsinosa</Emphasis> and <Emphasis Type="Italic">Palaemonetes africanus</Emphasis> Responses to Concentrations of Neatex and Norust CR486 in Sediment

The assessment of water and sediment quality from chemical pollutants in the Nigerian Niger Delta were conducted using bioindicators (Desmoscaris tripsinosa and Palaemonetes africanus). The Organization for Economic Cooperation and Development (OECD) (2004), No.218 direct sediment toxicity assessment was employed. Shrimp were exposed to sediments treated with Neatex (liquid detergent) and Norust CR 486 (corrosion inhibitor) at concentrations of 31.25, 62.5, 125, 250 and 500 mg/kg. Percentage mortality was measured as the ecological endpoint. Mean % mortality and estimated lethal concentration LC50 values varied with species type, concentration and exposure duration. Observed % mean mortality of the test organisms in both chemicals were significantly different from that of the control test suggesting that mortality may be induced by the effect of the chemicals. LC50s were significantly different for both chemicals at p < 0.05, t = 6.06 (fresh water) and p < 0.05, t = 12.34 (brackish). The values from this study are an indication that the chemicals have the potential to cause acute lethal toxicity. It is a prediction of likely adverse effects on shrimp populations in benthic sediment of the Niger Delta ecological zone. Consequently, there is a great need to protect some of the more sensitive invertebrates representing the major proportion of the diet of many other species.

响应面优化超声波辅助虾壳快速脱盐工艺

为降低虾壳中的含盐量,应用超声波辅助法对虾壳进行脱盐处理。以虾壳脱盐率为衡量指标,探讨虾壳粒径大小、浸泡时间、浸泡温度、液料比和超声时间等因素对虾壳脱盐的影响,在单因素试验基础上应用响应面分析法(response surface methodology,RSM)进一步优化,确定虾壳脱盐的最佳工艺为:浸泡温度55℃,浸泡时间15 min,液料比9∶1(mL/g),超声时间12 min,此时虾壳脱盐率可达到89.47%,与预测值相符,脱盐后虾壳中的盐和蛋白含量显著减少,钙、虾红素、甲壳素含量有所增加。     

人造肉生产技术相关专利分析

对近年来国内外关于人造肉生产技术相关的专利申请状况进行了分析,通过对历年专利申请趋势、主要申请人和发明人、专利布局情况的统计和对重点专利技术内容的解析,力求能全面系统地反映包括植物蛋白肉和细胞培养肉生产技术、人造肉商品化技术、人造肉重塑成型技术领域专利技术的发展及现状,寻找相关专利技术在发展中还存在的问题,并针对这些问题提出了下一步的研究方向,以期对尽早实现我国人造肉的规模化生产提供参考。     

乐清湾北部及嵊泗区域养殖贝类肌肉中镉含量调查及健康风险评估

目的 进行乐清湾北部及嵊泗区域养殖贝类肌肉中镉含量调查并探讨通过摄食途径可能导致的健康风险。方法 测定2016～2018年间采自乐清湾北部缢蛏、青蛤及嵊泗区域紫贻贝等三种养殖贝类肌肉中镉含量水平,与国家限量标准进行比对,并运用单因子污染指数(Pi)评估样品中镉污染程度,并以目标危害系数(THQ)和目标致癌风险(TR)为考量指标,评估通过摄食途径可能导致的健康风险。结果 三种肌肉样品中镉检出率为100%,但超标率为0。含量平均值总体比较：紫贻贝﹥缢蛏﹥青蛤。结论 本研究中所有样品Cd 单项污染指数的Pi 值均远低于1.0 ,绝大部分为正常背景水平,少量呈轻度污染水平。健康风险评估结果显示,所有样品THQ 值均小于安全基准值1.0,数据表明暴露人群没有明显的非致癌健康风险。TR的评价结果均在美国环保署推荐的可接受风险值(10_^-6～10_^-4)范围内,但也有部分样品超过了国际辐射防护委员会(ICRP)推荐的最大可接受风险值(5.0×10_^-5),需引起关注。     

工艺条件对凝固型发酵蛋奶生产的影响

以新鲜鸡蛋、乳粉（或相当数量的牛奶）、白砂糖为主要原料,通过适当的预处理后,添加乳酸菌发酵而制成酸凝蛋乳。原料的预处理等工艺条件对产品有显著的影响。     

云南省淡水湖泊鱼虾中多氯联苯食用安全性评估

目的对云南省5个淡水湖泊中鱼虾体内的多氯联苯(polychorinated biphenyl,PCBs)污染水平进行调查研究。方法采用气相色谱-质谱联用仪进行检测分析,根据检测结果对云南省淡水湖泊中的鱼虾体内多氯联苯的含量进行食用安全性评估。结果云南省淡水湖泊中鱼虾体内的多氯联苯检出率为90%,多氯联苯的含量范围为ND～1.16μg/kg,平均含量为0.27μg/kg,低于国家标准限量。云南省淡水湖泊中鱼虾体内的多氯联苯按照世界卫生组织(World Health Organization,WHO)规定的多氯联苯毒性当量(toxic equivalent quantity,TEQ)分布于ND～6.51×10~(-5)μg/kg,平均值为1.21×10~(-5)μg/kg,低于欧盟的行动标准限量。结论云南省居民从云南省淡水湖泊鱼虾体内摄入持久性有机污染物多氯联苯的剂量较低,引起的健康风险较低。     

Effects of freezing and thawing methods and storage time on thermal properties of freshwater prawns (Macrobrachium rosenbergii)

Thermal stability of proteins in frozen and thawed freshwater prawns was measured by differential scanning calorimetry. The onset and peak melting temperatures corresponding to myosin denaturation, as well as total enthalpy of denaturation of prawn muscle, decreased after freezing–thawing treatments. There were no significant differences in the thermal properties of prawns with changes in the rate of freezing, ie blast (fast) vs still (slow) freezing. However, the thermal properties were influenced by the rate of thawing. Rapid thawing using a combination of microwave and tap water resulted in a lower (P⩽0·05) thermal stability of prawn proteins compared to slow (refrigeration) or moderately fast (tap water) thawing methods. Keeping prawn shells intact or not intact during freezing–thawing did not alter the thermal properties of the prawn proteins. © 1997 SCI.     

不同加热方式下凡纳滨对虾品质的比较分析

本文探讨了水煮、蒸汽、焙烤、油炸、微波五种加热方法对对虾的重量减少率、色泽、弹性、蛋白质溶解性和综合感官品质的影响,同时研究了各项指标的规律。结果表明,焙烤加热减少虾仁的重量幅度最大,水煮则相反;水分的减少一定程度上能够影响虾仁表面的色泽,蒸汽加热与水煮加热能提升虾仁的亮度,蒸汽加热能够使虾仁颜色偏红,油炸加热会使虾仁颜色偏黄;油炸与焙烤加热能够保持虾仁的弹性及硬度,进而提升其咀嚼性;而蛋白质溶解度一定程度反映了不同加热条件下对虾蛋白质的变性程度,水煮加热能够最大程度稳定离子键,蒸汽加热能够增强疏水作用,微波加热可以增加氢键。综合色泽,香气,滋味,质地等多方面因素的感官评定结果表明微波加热对虾产品的感官评定分数最高。