Cáscara sagrada (Rhamnus purshiana DC): influence of the form of preparation of tea in the extraction of the active principle Elaine Cristina Lopes Guimarães Gibertoni, Walber Toma, Luciana Lopes Guimaraes

Abstract

Considering the need for standardization of methods for the preparation of teas and taking into account the instructions contained in Brazilian legislation ANVISA RDC 10/2010, the purpose of the present study was to evaluate the form of preparation of cáscara sagrada tea (Rhamnus purshiana DC), a medicinal plant with laxative action in the extraction of its active ingredient 1,8-Dihydroxyanthraquinone. Cáscara sagrada in the form of vegetable drug (stem bark), intended for the preparation of teas, was purchased from three manufacturers in pharmacies located in the city of Santos / SP. Two extractive methods were used in the present study for the preparation of Cáscara Sagrada teas: decoction (established in RDC 10/2010) and infusion, both popular methods in the preparation of teas. Extractions were performed according to the recommended ratio by RDC 10/2010 of 0.5 g dry plant / 150 mL of water and were also performed according to the manufacturers recommendations, appearing on the labels of each brand. The active ingredient (anthraquinone) content of the preparations was determined by reading at a 490 nm spectrophotometer using the 1,8-dihydroxy anthraquinone standard for constructing the calibration curve. The information contained in the teas labels was also evaluated according to RDC 10/2010. The results obtained in the present study clearly demonstrated the influence of the method of preparation of cáscara sagrada tea in the extraction of the active ingredient (anthraquinones), either by differences in the drug / water ratio or in the mode of preparation (decoction vs. infusion). Of the three manufacturers analyzed, only one brand was closest to the preparation recommendations in accordance with RDC 10/2010, as well as the availability of label information according to the same resolution. The data obtained in this study indicate that greater supervision should be applied to the commercialization of teas in order to avoid problems such as the absence of the desired therapeutic effect or even intoxication of the user.