Non-targeted electrospray mass spectrometry-based metabolic fingerprinting and PLS-DA-based classification of Brazilian "Malvas"

Abstract

Malva sylvestris, popularly known as "malva" in Brazil, is a medicinal plant used for its antiinflammatory effects. However, multiple plants are known as "malvas" in Brazil; these species include Sida cordifolia ("malva-branca") and Pelargonium graveolens ("malva-cheirosa"). In this work, electrospray mass spectrometry metabolic fingerprints from these species were obtained by direct infusion of extracts of commercial samples, purchased as crushed dried leaves. The spectral data were used to classify these species using a partial least squares discriminant analysis method. The identities of all samples were confirmed by morphological analyses, emphasizing the trichomes morphology. While over 80% of the samples were labeled as M. sylvestris or "malva", in the present study only 37% of these samples were classified as M. sylvestris species. Approximately 50% of these samples were classified as S. cordifolia, whose consumption may be dangerous for patients with cardiovascular diseases. Thus, these analytical and chemometric procedures worked as a fast and simple method for classifying species of "malvas".