Species and age determination of central nervous system tissue by fatty acid patterns.
The banning of specified risk materials (SRMs) from food chain is one of the most important measures to protect the consumer against any exposition with the agent of transmissible spongiform encephalopathies (TSEs). In order to control the SRM-ban, suitable methods for the detection of SRMs have to be developed. In this study homogenized samples of central nervous system (CNS) tissue from cattle (n=38), sheep (n=38) and pig (n=40) were analyzed by gas chromatography-mass spectrometry (GC-MS). The analysis was focused on the identification of fatty acid ratios for species differentiation and age estimation. We found a novel fatty acid ratio (C24:1(n-9)/(n-7))/(2OH-C24:1(n-9)/(n-7) for species differentiation. For the first time, we used multivariate analysis for species differentiation, based on fatty acid ratios. It showed an excellent predictive ability (Q_(cum)(2))Q_(cum)(2)=0.842. For age estimation in cattle CNS we discovered a novel fatty acid ratio 2OH-C25:0/2OH-C24:1(n-7). The ratio is strongly correlated with age (coefficient of correlation (r)=0.935, Spearman-Rho). The corresponding regression analysis which allows the prediction of age by this ratio was acceptable (coefficient of determination (R(2))=0.831).
Griessbach
Maria
M
Institute of Food Hygiene, University of Leipzig, An den Tierkliniken 1, Leipzig, Germany. griesbach@vmf.uni-leipzig.de
Hartmann
Franziska
F
Massag
Nicole
N
Baumann
Daniela
D
Krex
Christian
C
Biedermann
Wolfgang
W
Truyen
Uwe
U
Lücker
Ernst
E
D000375:Aging; D000818:Animals; D001923:Brain Chemistry; D002417:Cattle; D005227:Fatty Acids / Q000032:analysis* / Q000302:isolation & purification; D005504:Food Analysis / Q000379:methods; D008401:Gas Chromatography-Mass Spectrometry / Q000379:methods*; D009417:Nerve Tissue / Q000737:chemistry*; D012756:Sheep; D013045:Species Specificity; D013552:Swine
D005227:Fatty Acids