Formation of Glycated Products and Quality Attributes of Shrimp Patties Affected by Different Cooking Conditions

ABSTRACT

The objective of this study was to firstly investigate the impact of the cooking conditions, including boiled, baked, and microwaved treatments, in the presence of 3% powdered sugar and 1% NaCl on the changes of quality attributes and the formation of glycated products in shrimp patties. The levels of carboxymethyllysine (CML), furosine, and fluorescent intensity in boiled shrimp patties were much lower than that in baked shrimp patties and microwaved shrimp patties. Addition of powdered sugar alone in baked shrimp patties and microwaved shrimp patties increased the level of furosine and fluorescent intensity. Furthermore, sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) analysis showed a notably decreased intensity in the band with MW of 17–22 kDa in boiled shrimp patties and microwaved shrimp patties, and a stronger intensity of band, with MW of 75–100 kDa, in baked shrimp patties. Principal components analysis (PCA) further confirmed that the changes of quality attributes and glycated products in shrimp patties caused by cooking methods were greater than that caused by the addition of powdered sugar or NaCl.     

数值模拟秸秆热解过程影响要素及其应用分析

为进一步明确秸秆热解过程的影响因素及其相互作用,本研究系统分析2000—2018年国内外秸秆热解研究的相关文献,总结秸秆热解研究中存在的问题。从数值模拟分析的角度对影响秸秆热解过程的因素进行归纳分类,分析数值模拟中需要考虑的因素及其应用,如基于非稳态数值模拟可实时监测秸秆热解过程中装置内部瞬时温度分布、挥发分流动路径、秸秆颗粒流动规律及浓度分布等瞬态物理量变化。阐述将CFD数值模拟与试验测试、理论推导相结合来研究秸秆热解的必要性,并分析此种研究方式的可行性。     

Molecular cloning and characterization of a novel gene encoding an EF-hand calcium-binding protein related to fruit seedlessness of grapevine

EF-hand calcium-binding protein (CBP) gene plays a critical role during embryonic development in animals, but it remains unclear whether this gene possesses similar function in plants. In this study, a novel CBP gene was isolated from Vitis vinifera cv. Thompson Seedless and designated as VvCBP1. Using a combination of sequence structural investigation, expression pattern analysis of different embryo development in grapevine, and silencing assay of VvCBP1 homolog in tomato, the functional role of VvCBP gene in embryo development of seedless grapevine was studied. Structural investigations showed that VvCBP1 is 907 bp in length, and contains two EF-hand motifs. Expression pattern of this gene is different in embryo between seedless and seeded grapevine species. Moreover, the silencing of homology gene led to the seeds number significantly decreased in tomato. These data demonstrate clearly that VvCBP1 plays an important role in embryo development of seedless grapevine.     

类Fenton试剂处理苯酚废水的影响因素及动力学研究

采用一种类Fenton试剂法,即Fe3+和H2O2的组合代替Fe2+和H2O2的组合法,对氧化降解苯酚的影响因素及反应动力学进行研究。结果表明:当Fe3+、H2O2的加入量分别为1.3×10-3和1.3×10-2mol·L-1,且初始pH值约为4时,苯酚的降解率最大,几乎达到100%。同时分别用一级动力学、二级动力学及复合一级动力学方程对该条件下的反应进行拟合,复合一级动力学方程能最佳拟合相应的动力学过程,但2个平行反应的速率系数k1≈9.24k2,因此可近似认为是一级动力学过程。     

小麦叶锈菌效应蛋白Pt18906激发TcLr27+31的双层防御反应

【目的】由小麦叶锈菌（Puccinia triticina）引起的小麦叶锈病是影响小麦生产的主要病害之一,在小麦与叶锈菌互作的过程中病菌向寄主细胞分泌效应蛋白,以调控寄主防御反应、发挥毒性功能。开展对小麦叶锈菌效应蛋白的研究,探索小麦叶锈菌的致病机制,为病害的持续防控提供依据。【方法】以小麦叶锈菌13-5-72与感病品种Thatcher互作的cDNA为模板扩增效应蛋白Pt18906,通过SignalP 4.1、TargetP 1.1、TMHMM 2.0和EffectorP 2.0软件对Pt18906进行序列特征分析,利用在线软件Swiss-Model预测Pt18906的三级结构,利用在线软件SOPMA预测Pt18906的二级结构。采用实时荧光定量PCR对Pt18906的表达模式进行分析,借助于烟草的异源表达系统对Pt18906进行抑制Bax和INF1诱导的细胞程序性死亡（programmed cell death, PCD）能力验证,利用酵母系统验证Pt18906的信号肽是否具有分泌功能,采用氨基酸逐步缺失的方法缺失突变Pt18906,从而确定其功能毒性motif;通过在烟草中瞬时表达Pt18906-GFP融合蛋白,结合质壁分离技术分析Pt18906的亚细胞定位,得出效应蛋白的作用位点;利用瞬时表达技术在以Thatcher为背景的不含抗病基因和含有不同抗病基因的全套近等基因系上开展Pt18906无毒性功能分析;采用细菌三型分泌系统（Type Ⅲ secretion system）介导的瞬时转化分析Pt18906对寄主防御反应的调控。【结果】从小麦叶锈菌13-5-72与感病品种Thatcher互作6 d的转录组文库中获得一个在接种24 h后显著高表达的、基因全长序列672 bp、编码223个氨基酸的候选效应蛋白Pt18906,该效应蛋白缺乏已知的功能结构域和保守基序,工作环境偏碱性,在烟草细胞中瞬时表达Pt18906,Pt18906能够抑制Bax和INF1诱导的细胞程序性死亡,表明该效应蛋白具有毒性功能,并且通过构建缺失突变体明确其28—47位氨基酸对其毒性功能具有重要作用,该效应蛋白定位于细胞核和细胞质,表明其作用于细胞内。Pt18906在单基因系抗病品种TcLr27+31和TcLr42上能够引起过敏性坏死反应,表明该效应蛋白的无毒性,Pt18906能够引起TcLr27+31中胼胝质的积累和活性氧的迸发,胼胝质随注射时间的增加而逐渐积累,活性氧在注射后的10 min达到最高。【结论】位于28—47位的氨基酸决定Pt18906的毒性主要功能,Pt18906能激发小麦TcLr27+31双层防御反应。     

干燥温度对黑参加工过程中美拉德反应主要指标成分变化的影响

以4年生鲜人参为原料，在高温灭菌锅内110 ℃蒸制2 h，鼓风干燥箱内设置温度分别为50、60、70 ℃，干燥12 h，如此重复炮制9次以制备黑参。通过测定黑参加工过程中的美拉德反应主要指标成分（还原糖、氨基态氮、类黑精、水分、多酚）的含量变化，确定黑参的适宜干燥温度。结果表明，黑参加工过程中随着炮制次数的增加，还原糖和多酚含量均呈先升高后下降的趋势，温度越高，还原糖和多酚含量先升高后下降的速度越快；氨基态氮含量逐渐下降，温度越高下降越快；类黑精含量逐渐升高，温度越高升高越快；含水量逐渐下降，温度越高含水量越低。干燥温度升高能加速美拉德反应褐变的进程，70 ℃的干燥条件优于其他两个温度。     

Surveillance of Francisella tularensis in surface water of Kurdistan province,west of Iran

BackgroundThe etiologic agent of tularemia, Francisella tularensis, is transmitted to humans via ingestion of contaminated water or food, arthropods bite, respiratory aerosols, or direct contact with infected animals body fluids or tissues. In the current study, due to the importance of water in transmitting the disease and the report of the disease in different regions of Iran, surface water of Kurdistan province were evaluated for the presence of F.tularensis.Materials and MethodsSampling was carried out in five-counties of Kurdistan province. Sixty-six specimens of surface water were collected. The detection was carried out by targeting ISFtu2 and fopA genes using TaqMan real-time PCR. Moreover, the samples were both cultured and inoculated into NMRI inbreed mice. Spleens of inoculated mice and bacterial isolates were tested by TaqMan real-time PCR.ResultsDespite the lack of isolation of F. tularensis, the results of the molecular testing indicate the presence of bacteria in surface water. Molecular positivity of one sample (1.51%) was confirmed using a real-time PCR for both ISFtu2 and fopA genes. Moreover, 4.54% of the samples were positive for ISFtu2.ConclusionSince the in vitro isolation of bacteria from environmental samples is associated with a very low success rate and depends on various environmental parameters, the use of molecular techniques for monitoring of the bacteria in the contaminated areas is fully recommended.     

红三叶异黄酮在刈割6 h内的变化规律

以豆科牧草红三叶(Trifolium pratense L.)为试验材料,研究6 h内连续刈割后‘炫丽’和‘海发’两品种的叶片和茎秆中抗逆物质异黄酮的含量变化。结果表明,叶片和茎秆的异黄酮总含量在刈割后均明显增加。4种异黄酮类化合物在不同品种和部位中表现出不同的变化趋势。鹰嘴豆素A、芒柄花素含量在‘炫丽’叶片、茎秆刈割3 h后显著增加,而在‘海发’的叶片中表现为下降趋势。大豆苷元含量除在‘炫丽’叶片中保持不变,在其余样品中增加,在茎秆中增加显著。染料木素含量最低,刈割后在‘海发’叶片中增加,‘炫丽’茎秆中显著增加,其余均呈下降趋势。综上可知,异黄酮是红三叶受到刈割后的主要应激响应物质之一,与植物体的再生和恢复密切相关。     

浅谈定向质谱法验证蛋白质生物标记物

特异性生物标记物的发现有益于疾病的早期诊断,促进靶向治疗的发展,并提供精确的治疗反应监控方法。血浆中候选生物标记物的验证过程中的一个主要问题是血浆中蛋白质浓度的动态范围非常广。本文回顾了当前能够在所预期的血浆浓度范围内(如ng/ml浓度水平)量化候选生物标记物的定向蛋白质组学策略。另外,提供了基于定向质谱法,可对大部分候选生物标记蛋白进行快速验证的技术流程。这些公开数据库中的技术对生物标记的验证研究中的处理量具有极大影响潜力。