Determination of citrus fruit origin by using 16S rDNA fingerprinting of bacterial communities by PCR- DGGE: an application to clementine from Morocco and Spain

Abstract

--Introduction. Consumption of citrus fruits and their juice has strongly grown in the last few decades. However, at the present time, the traceability of these fruits is only documentary. In case of doubt or fraud, no standardized analysis makes it possible to discriminate or determine the geographical origin of culture of the fruit. Materials and methods. A method of bacterial ecology, PCR-DGGE, was used to characterize the bacterial flora of clementines imported into France from Spain and Morocco in order to show that there is a relation between the bacterial communities of the fruits and their geographical origins. The principle rests on the determination of specific biological markers for a given region. Protocols of microbial extraction and DNA amplification were optimized. Results. DGGE profiles analyzed by multivariate analysis permitted us to distinguish microbial communities from different origins. Conclusion. We propose the PCR-DGGE method as a new tool for traceability that provides citrus products with a unique bar code and makes it possible to trace back the citrus fruit to their original location. Résumé --introduction. La consommation des agrumes et de leur jus s'est fortement déve-loppée pendant ces dernières décennies. Cependant, à l'heure actuelle, la traçabilité de cette filière est uniquement documentaire. En cas de doute ou de fraude, aucune analyse normalisée ne permet de discriminer ou de déterminer l'origine géographique de la culture du fruit.

Tracing insect pests: is there new potential in molecular techniques?

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Biological bar code for determining the geographical origin of fruits using 28S rDNA fingerprinting of fungal communities by PCR-DGGE: an application to Shea tree fruits

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