Application of electrospray ionization mass spectrometry fingerprinting associated with macroscopic and histological analysis for Plantago major herbal infusions quality control.

The present study demonstrates the need to conduct an integrative quality control of teas marketed as Plantago major. In the present study, quality control checks were performed through macroscopic, microscopic and chemical analyses of commercial brands. Leaves with parts not allowed for consumption were found in all brands. Six brands showed histological similarity <50% with the authentic P. major. Eight brands demonstrated low chemical similarity (40 to 60%), indicating that they do not have the same compounds from the authentic P. major. All commercial samples are contaminated with aflatoxins, indicative of fungicide contamination and consequent degradation of phenolic compounds and reduction of antioxidant activity from the commercial samples. The difference in the present study is the integrative application of methods for success in the quality control of P. major, which can be applied to other species. Thus, more rigorous inspection actions in the production of teas to guarantee the therapeutic benefit of these products.