Covalent attachment of single-stranded DNA to carbon paste electrode modified by activated carboxyl groups

A new method of the electrode modification and DNA immobilization for a biosensor is reported. Outer layer of a conventional carbon paste electrode (CPE) was modified with carboxyl groups by mixing stearic acid with the paste. Single-stranded deoxyribonucleic acid was attached to the modified electrode through a linker - ethylenediamine. Immobilization process was performed in the presence of activators - water soluble 1-ethyl-3(3′-dimethylaminopropyl)-carbodiimide (EDC) and N-hydroxysulfosuccinimide (NHS). Stearic acid concentration and other experimental parameters of the procedure were optimized. Covalent immobilization of DNA on the electrode surface exhibits some advantages as compared to simple adsorption mainly due to the fact that nucleic acid chains are bound to an electrode surface by one end only and it ensures structural flexibility and increases hybridization without DNA leakage. Modified electrode with immobilized (21-mer) oligonucleotide as a specific probe was successfully applied in preliminary investigations for the detection of bar gene commonly used in genetically modified food.     

突出实践能力培养,构建层次化课程教学体系

要提高学生的实践能力,就需要构建科学合理的课程教学体系。我校结合应用型人才的办学定位,对食品科学与工程专业人才的课程教学体系进行了优化改革,体现层次化的特征,分阶段实现人才培养目标。这一体系的构建增强了人才培养的有效性和目的性,也为未来进一步提升专业教学质量提供了良好的基础。     

β-Conglycinin Reduces the Tight Junction Occludin and ZO-1 Expression in IPEC-J2

Soybean allergy presents a health threat to humans and animals. The mechanism by which food/feed allergen β-conglycinin injures the intestinal barrier has not been well understood. In this study, the changes of epithelial permeability, integrity, metabolic activity, the tight junction (TJ) distribution and expression induced by β-conglycinin were evaluated using IPEC-J2 model. The results showed a significant decrease of trans-epithelial electrical resistance (TEER) (p < 0.001) and metabolic activity (p < 0.001) and a remarkable increase of alkaline phosphatase (AP) activity (p < 0.001) in a dose-dependent manner. The expression levels of tight junction occludin and ZO-1 were decreased (p < 0.05). The reduced fluorescence of targets and change of cellular morphology were recorded. The tight junction occludin and ZO-1 mRNA expression linearly declined with increasing β-conglycinin (p < 0.001).     

果蔬保鲜剂的研究进展

针对果蔬在采摘后由于呼吸生理代谢、病原微生物侵染、储藏方法不当等问题引起腐烂损耗问题,人们常常利用化学保鲜剂与生物保鲜剂来抑制这些对果蔬贮藏的不利因素。果蔬保鲜剂的特性来可分为三大类:生物保鲜剂、化学保鲜剂、食品添加剂型保鲜剂,本文分别阐述了化这三类保鲜剂对果蔬保鲜的作用原理、发展现状和各自优缺点。并对今后果蔬保鲜剂的进展提出一些见解。     

食品安全检验中高效液相色谱法的应用现状

食品安全检验是社会普遍关注的焦点,本文主要介绍高效液相色谱法及高效液相色谱-质谱法联用的特点,并针对其在食品检验领域中的应用展开论述。     

Metabolomics of Genetically Modified Crops

Metabolomic-based approaches are increasingly applied to analyse genetically modified organisms (GMOs) making it possible to obtain broader and deeper information on the composition of GMOs compared to that obtained from traditional analytical approaches. The combination in metabolomics of advanced analytical methods and bioinformatics tools provides wide chemical compositional data that contributes to corroborate (or not) the substantial equivalence and occurrence of unintended changes resulting from genetic transformation. This review provides insight into recent progress in metabolomics studies on transgenic crops focusing mainly in papers published in the last decade.     

基于PLC和触摸屏的食品包装自动化生产线控制系统设计

为了提高食品包装生产线自动化水平,减轻工人的劳动强度,以食品(槟榔)包装生产线改造为例,分析设计了改造后槟榔包装生产线的工艺流程。结合槟榔包装的特点以及技术要求,给出了槟榔包装生产线的总体设计方案。采用三菱公司PLC和触摸屏设计了生产线控制系统,实现食品包装自动化。实际生产表明,该自动化生产线构造合理,可以满足槟榔包装生产自动化需求,具有广阔的应用前景。     

表面解吸常压化学电离质谱法快速鉴别羊肉真伪

采用自行研制的表面解吸常压化学电离源（DAPCI）,在无需样品预处理的条件下,通过DAPCI-MS方法直接获取不同肉类样品（鸭肉、牛肉、猪肉、羊肉、自制假羊肉）的指纹谱图。采用主成分分析（PCA）方法对指纹谱图信息进行数据分析,以区分不同肉类样品。结果表明：鸭肉、牛肉、猪肉、羊肉和自制假羊肉的指纹谱图之间存在差异,采用PCA方法能较好地区分这些肉类样品。本方法无需样品预处理,分析速度快,可实现高通量肉类的快速鉴别,为食品安全中辨别肉类样品提供了一种快速、高效的分析方法。     

GC-QqQ-MS/MS法检测油脂类功能食品中辐照标志物2-十二烷基环丁酮和2-十四烷基环丁酮

建立了气相色谱-三重四极杆串联质谱（GC-QqQ-MS/MS）同时检测油脂类功能食品中辐照标志物-2-烷-基环丁酮（2-ACBs）类化合物中2-十二烷基环丁酮（2-DCB）和2-十四烷基环丁酮（2-TCB）的方法。样品用正己烷溶解,过ProElut Silica固相萃取柱净化。结果表明,2-DCB和2-TCB与基质干扰峰得到较好的分离,在0.005~1.0 mg/L浓度范围内,峰面积与浓度呈良好的线性关系,线性相关系数（R²）大于0.999。在油脂类功能食品中添加0.01、0.05、0.10 mg/kg水平的2-DCB和2-TCB,平均加标回收率为85.6%~97.1%,相对标准偏差（RSD）小于7.0%（n=6）,方法定量限（LOQ）为5 μg/kg。该方法操作简便、耗时短、灵敏度高、稳定性好,能为油脂类功能食品中辐照标志物的检测提供理论依据。     

食品添加剂在肉制品加工中的应用

食品添加剂种类繁多,直接关系着人们的食用安全和身体健康,是现代食品工业的重要组成部分,影响着整个食品工业的发展,食品添加剂在肉制品加工中发挥了重要作用,表现在改善肉制品品质和色、香、味、形、原料及成品的保质保鲜,提高食品的营养价值,新产品的开发及食品加工工艺等方面,通过几种常见的食品添加剂,探讨其在肉制品加工过程中的应用。