Lange Bianca, Alter Thomas, Froeb Annekathrin, Lücker Ernst
Institut für Lebensmittelhygiene, Veterinärmedizinische Fakultät, Universität Leipzig.
Berl Munch Tierarztl Wochenschr. 2003 Nov-Dec;116(11-12):467-73.
In principle, molecular biological methods can be used for the detection of specified risk material (SRM) in meat products. We were able to identify suitable target mRNAs for the marker proteins glial fibrillary acidic protein (GFAP) and myelin basic protein (MBP) of tissues of the central nervous system (CNS). The selected primers for GFAP ("GFAP87") and MBP ("MBP51") facilitated the detection of CNS in non-heated and heated standards of emulsion type (and raw) sausages with defined addition of brain by reverse transcription and polymerase chain reaction (RT-PCR). Stability of the mRNA proved to be given over a minimum of 48 hours. First results indicate an even higher stability of the target mRNAs over time and an ample stability against meat technological influences such as storage, temperature, and ripening. RT-PCR with GFAP87 facilitates the detection of CNS of all relevant slaughter animals in meat products. Thus it can be applied in food labeling control. Using RT-PCR and MBP51 as primer we were able to detect selectively the CNS of bovines, ovines and caprines but not CNS of porcines and poultry. Thus we have a second RT-PCR detection procedure for CNS in meat products which, however, yields results equivalent to the legal definition of SRM. The further development of these molecular biological methods would be of considerable importance for routine food control and reduction of human TSE-exposure risk.
原则上,分子生物学方法可用于检测肉制品中的特定风险物质(SRM)。我们能够为中枢神经系统(CNS)组织的标记蛋白胶质纤维酸性蛋白(GFAP)和髓鞘碱性蛋白(MBP)鉴定出合适的靶mRNA。针对GFAP(“GFAP87”)和MBP(“MBP51”)选择的引物,通过逆转录和聚合酶链反应(RT-PCR),有助于在添加了明确脑成分的非加热和加热的乳化型(及生)香肠标准品中检测中枢神经系统。mRNA的稳定性被证明至少在48小时内保持。初步结果表明,随着时间推移,靶mRNA具有更高的稳定性,并且对肉类加工过程中的影响因素如储存、温度和成熟具有足够的稳定性。使用GFAP87进行RT-PCR有助于检测肉制品中所有相关屠宰动物的中枢神经系统。因此,它可应用于食品标签控制。使用RT-PCR并以MBP51作为引物,我们能够选择性地检测牛、羊和山羊的中枢神经系统,但不能检测猪和家禽的中枢神经系统。因此,我们有了第二种用于检测肉制品中中枢神经系统的RT-PCR检测方法,然而,其结果等同于SRM的法定定义。这些分子生物学方法的进一步发展对于常规食品控制和降低人类感染传染性海绵状脑病(TSE)的风险具有相当重要的意义。