Novel Protein- and DNA-Based Methods for Tracing of Food Components
Coordinating Institution:
CRP Sante
Contracting Partner(s):
Laboratoire National de Santé
Other Partner(s):
Universität des Saarlandes
From: 01/11/2004
To: 30/04/2008
Budget: 1,019,983.00€
Contact(s):
Hentges François
,
Steinmetz André
Summary
Specific identification of animal and plant components in processed food is a major safety topic in food industry. European food authorities guide the progress in this matter by appropriate directives on food labeling and high standards of food authentication, quality and safety. Labeling legislations ensure that food is properly described. This supports allergic consumers’ protection since potential allergenic substances must be indicated in the list of ingredients. Implementation of food authentication regulations helps to avoid mislabeling of lower value products.
The objective of this project is to develop methods and tools for specific detection of animal and plant components in food. For the intended tracing assays, novel DNA-based methods include specific amplifications of unique genomic DNA sequences. The protein-based approach comprises the use of specifically-raised monoclonal antibodies. The approach to choose allergens as tracer molecules gives the possibility to match a double goal, first to perform food tracing and second, allergen detection. The allergenic plant lipid transfer proteins (LTPs) and parvalbumins from animal origin were considered suitable target proteins.
With regard to material of animal origin, different fishes, poultry and mammals were chosen as target species for food tracing purposes. A panel of recombinant fish parvalbumins was produced and allowed the production of monoclonal antibodies. The monospecific antibodies are tools for tracing purposes, while the crossreactive antibodies are intended for allergen detection. In addition, the purified parvalbumin preparations proved useful in the clinical diagnosis of fish allergy. Using PCR-based techniques, detection and identification of tracers was realized for food animal species using genomic sequences from parvalbumins. Systematic tests using the specific PCRs were performed for evaluation of their specificity, sensitivity and reproducibility. An oligonucleotide microarray was also designed to discriminate several fish species in food samples based on the identification of orthologous genes encoding for parvalbumin. Benchmarking experiments showed that the biochip has a good level of specificity, indicating that it could be a valuable tool for food tracing. In the case of plants, PCR-based assays were also developed that allow identification of several cereals and nuts in processed food like bread.
As to the screening of food for genetically modified organisms, a quadruplex-real-time-PCR method was developed that allows rapid and simultaneous screening of food for the presence of target DNA sequences from the cauliflower mosaic virus 35S promoter, the NOS terminator from Agrobacterium tumefaciens, the soya reference lectin gene and the maize reference alcool dehydrogenase (adh) gene.
Refereed Scientific Publications:
- Gaudron T. et al. “Development of a quadruplex-Real-Time PCR for screening food for genetically modified organisms (submitted for publication)
Other Publications:
- Poster presentation at ISMA 2008, Salzburg (Kuehn A. et al. “IgE binding to chicken alpha parvalbumin”); oral poster presentation at EAACI 2008, Barcelona (Kuehn A et al. “Anaphylaxis to fish gelatin“) ; Hentges F, Kuehn A. Anaphylaxie par sensibilisation à la gélatine de poisson. Journée d’Actualités en Allergologie, Strasbourg, 7 March 2008