High-resolution melting analysis for testing the authenticity of fresh and canned heart of palm, an economically important non-timber forest product from the Neotropics

ABSTRACT

Background: Wild Euterpe edulis has been a source of heart of palm for many decades. Today, this species is threatened with overexploitation and cultivated E. oleracea and Bactris gasipaes are replacing it as a source of the vegetable. However, morphological identification of both fresh and canned heart of palm is not simple, favouring adulteration and illegal trade.

Aims: We developed and tested a rapid and efficient DNA-based approach for authenticating heart of palm from E. edulis, E. oleracea and B. gasipaes.

Methods: Eight cpDNA loci were sequenced and screened for polymorphisms. The psbK-I locus contained SNPs that were used to authenticate fresh and canned heart of palm samples according to species type through High Resolution Melting (HRM) analysis.

Results: All fresh and canned commercial samples were successfully amplified in HRM analysis and SNP profiles distinguished the putative species indicated by producers on package labels, demonstrating the robustness of the assay.

Conclusions: The results demonstrated that HRM is a fast and reliable screening technique that can ensure food safety and contribute to the conservation of endangered palm species.

KEYWORDS:

• Arecaceae
• Bactris gasipaes
• Euterpe edulis
• Euterpe oleracea
• cpDNA
• HRM
• NTFPs
• qPCR
• palmito
• tropical forest

Acknowledgements

We thank Instituto Chico Mendes de Conservação da Biodiversidade (ICMBio) for collecting permits. We thank Sítio Roberto Burle Marx and Horto Florestal de Guaratiba (RJ) for providing hearts of palm samples.

Disclosure statement

No potential conflict of interest was reported by the authors.

Supplemental material

Supplementary data for this article can be accessed here.

Additional information

Funding

This work was supported by Fundação Carlos Chagas Filho de Amparo à Pesquisa do Estado do Rio de Janeiro (FAPERJ) under grant numbers E-26/190.031/2012, E-26/190.185/2013 and E-26/010.000.228/2016; and by Universidade Federal do Estado do Rio de Janeiro (Edital Pesquisador UNIRIO de Produtividade em Pesquisa - 2016). Oliveira, K.T. received a master scholarship funded by Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES).

Notes on contributors

Karoline T. de Oliveira

Karoline T. de Oliveira was a M.Sc. student in conservation genetics when she undertook this research.

Camila M. Patreze

Camila M. Patreze is a lecturer with a general interest in molecular biology of plants and fungi.

Fabiano Salgueiro

Fabiano Salgueiro is a lecturer with a general interest in evolution; he leads a research group working on conservation genetics of neotropical species.