Characterization of odor-active compounds in cooked meat of farmed obscure puffer (Takifugu obscurus) using gas chromatography–mass spectrometry–olfactometry

The volatile and odor-active compounds in cooked meat of farmed obscure puffer (Takifugu obscurus) were analyzed by gas chromatography–mass spectrometry–olfactometry (GC–MS–O). The volatile compounds were extracted by the simultaneous distillation–extraction (SDE) method, then separated and identified by GC–MS. Odor-active compounds in the SDE extract were characterized by GC–MS–O. A total of 68 volatile compounds were found, including 23 aldehydes, 10 alcohols, nine ketones, 17 N- or S-containing compounds and aromatics, three acids, three alkanes, and three esters. Of these, 31 odor-active compounds were detected and identified. Trimethylamine (fishy), octanal (grassy, leafy, green), (E)-2-octenal (roast, fatty), 1-octen-3-ol (fishy, fatty, mushroom, grassy), 2-ethyl-1-hexanethiol (cooked fish), (E,E)-2,4-octadienal (cooked meat, sweet), 2-acetylthiazole (meaty, roast, nutty, sulfur), 2-acetylpyrrole (nutty, walnut, bread) were identified as the key odorants in the cooked meat of farmed obscure puffer based on posterior intensity and time-intensity methods.     

采用压差传感器测量医用气体流量的不确定度评定

目的：对采用压差法测量医用气体流量的测量原理、结构和工艺等因素引入的不确定度进行分析.方法：利用液体流经节流装置时所产生的压差测量气体流量.结果：合成不确定度μc=1.364％,满足产品设计要求.结论：压差传感器测量方法准确可靠,能够满足对医用气体流量测量的要求.     

Spanish smoked meat products: Benzo(a)pyrene (BaP) contamination and moisture

Traditional direct smoking is used for drying and flavouring foodstuffs, although carcinogenic compounds are added during this process, namely polycyclic aromatic hydrocarbons (PAH). The maximum permissible content of benzo(a)pyrene (BaP) (a current marker for the occurrence and effect of PAH in foods) in smoked meat products was reduced from 5 to 2 μg/kg on 1/09/2014, in compliance with European Regulation No. 835/2011. In this study, an analytical method has been developed to determine BaP content consisting of PAH extraction assisted by sonication followed by solid-phase extraction sample clean-up and analytical determination using gas chromatography/mass spectrometry. Sixteen commercial chorizo samples from 16 different Spanish producers from the Principality of Asturias were studied. Five of the samples exceeded the 2 ppb BaP limit. The relationship between moisture and BaP content in chorizo was examined, in order to verify the quality of the manufacturing process. Moisture content did not correlate with BaP content in chorizo.     

气相色谱-质谱联用法测定洁尔阴洗液中蛇床子素的含量

目的使用气相色谱-质谱联用仪,采用选择监测离子法测定洁尔阴洗液中蛇床子素的含量。方法 DB-5MS(30mm×0.32 mm×0.25μm)石英毛细管柱为色谱柱,大黄酚为内标,样品经过乙酸乙酯直接提取,选择离子监测法定量分析,监测离子为m/z=244。结果蛇床子素在1-100μg/m L(r=0.9986)范围内线性良好;平均回收率为98.3%,检测限为1.0 ng/m L。结论本方法简便、快速、灵敏度高、结果准确可靠,可以用于洁尔阴洗液中蛇床子素含量的测定。     

不同干燥工艺对鱼腥草挥发油的影响研究

目的研究不同干燥工艺对大别山鱼腥草挥发油的影响。方法分别用低温烘干(50℃)、晒干、阴干的干燥方式处理新鲜的鱼腥草,挥发油提取器提取挥发油,采用GC-MS检测分析。结果阴干、晒干、烘干鱼腥草中的挥发油分别鉴定出43、37和14种。结论晒干和低温烘干方式均会影响鱼腥草挥发油的组成,但对总体积影响不显著。     

中国药典气体灭菌法质量标准的分析与现状思考

目的 分析中国药典气体灭菌法质量标准与国外药典的差异以及对现状的思考,探索进一步提高和完善中国药典气体灭菌法标准的路径。方法 将美国药典、欧洲药典、日本药局方与中国药典收载的气体灭菌法质量标准进行比对,同时采取参阅其他文献和企业调研的方式展开研究。结果 中国药典与国外药典在气体灭菌法的质量控制上整体要求是一致的,但在一些方面还存在一定的差异性,如气体灭菌法的定义和范畴、生物指示剂的菌株种类和编码、物理化学指示剂的分类和异常说明、验证方法、灭菌剂残留的解析和检测等,需要通过充分的技术评估和可行性分析来逐步完善;此外我国大部分企业的硬件水平差距较为明显,如气体浓度探头的使用、灭菌柜循环系统的配备、热解析室的建立等,其根源很大程度上在于企业成本和发展观念的制约。结论 应根据我国实际情况,进一步完善我国气体灭菌法的国家标准,同时以提高技术标准为依托,推动我国气体灭菌企业转变思维模式和观念,不断优化工艺,提高整体行业水平。     

Characterization of Bioeffects on Endothelial Cells under Acoustic Droplet Vaporization

Gas embolotherapy is achieved by locally vaporizing microdroplets through acoustic droplet vaporization, which results in bubbles that are large enough to occlude blood flow directed to tumors. Endothelial cells, lining blood vessels, can be affected by these vaporization events, resulting in cell injury and cell death. An idealized monolayer of endothelial cells was subjected to acoustic droplet vaporization using a 3.5-MHz transducer and dodecafluoropentane droplets. Treatments included insonation pressures that varied from 2 to 8 MPa (rarefactional) and pulse lengths that varied from 4 to 16 input cycles. The bubble cloud generated was directly dependent on pressure, but not on pulse length. Cellular damage increased with increasing bubble cloud size, but was limited to the bubble cloud area. These results suggest that vaporization near the endothelium may impact the vessel wall, an effect that could be either deleterious or beneficial depending on the intended overall therapeutic application.