Molecular identification and phylogenetic analysis of Egletes viscosa (L.) Less., a traditional medicinal plant from Northeastern Brazil

Abstract

Macela (Egletes viscosa (L.) Less.) é uma erva medicinal utilizada para tratar distúrbios digestivos e intestinais. Estudos prévios revelaram a existência de dois quimiotipos de macela, cujos óleos essenciais são caracterizados pela presença de acetato de trans-pinocarveíla (quimiotipo A) ou acetato de cis-isopinocarveíla (quimiotipo B). A análise de sequências de DNA do espaçador transcrito interno (ITS/5,8S) revelou oito polimorfismos de base única (SNPs) e um sítio inserção/ deleção que diferenciam os dois quimiotipos. Além disso, foi possível identificar espécimes selvagens de E. viscosa pertencendo a ambos quimiotipos e amostras comerciais, obtidas em mercados locais, pertencendo somente ao quimiotipo A. A análise filogenética confirmou a posição taxonômica desses dois quimiotipos na tribo Astereae. Portanto, a análise de seqüências de DNA da região ITS/5,8S proporciona uma efetiva e acurada estratégia para identificar os quimiotipos A e B de E. viscosa."Macela" (Egletes viscosa (L.) Less.) is a medicinal herb used to treat digestive and intestinal problems. Previous studies revealed the existence of two chemotypes of "macela", whose essential oils are characterized by the presence of trans-pinocarveyl acetate (chemotype A) or cisisopinocarveyl acetate (chemotype B). Herein, DNA sequence analysis of the internal transcribed spacer region (ITS/5.8S) showed eight single nucleotide polymorphisms (SNPs) and one insertion/ deletion site that clearly distinguished the chemotypes of E. viscosa. Moreover, it was possible to identify wild specimens of E. viscosa belonging to both chemotypes and commercial samples, purchased at local markets, belonging only to chemotype A. The phylogenetic analysis confirmed their taxonomic position within the tribe Astereae. Therefore, analysis of ITS/5.8S DNA sequences provides an effective and accurate strategy for identifying the chemotypes A and B from E. viscosa.

Medicinal Plants and Herbal Products From Brazil: How Can We Improve Quality?

“…In another study done also with M. ilicifolia using PCR-RFLP technique, substitution was also an issue ( Nakamura et al, 2013 ). On the other hand, when analyzing the complete ITS/5.8S region in commercial samples of “Brazilian arnica ” ( Egletes viscosa (L.) Less), no substitutions were found ( Batista et al, 2012 ). In his review, Ichim concludes that the highest percentage of adulterated commercial HPs among all countries was reported for Brazil.…”