Recebido em 23/9/11; aceito em 27/11/11; publicado na web em 28/2/12Prior to obtain a standardized dried extract from V. ferruginea, lupeol was first time isolated from leaves and used as chemical maker. An analytical method using HPLC-PDA for lupeol determination in V. ferruginea intermediate products was developed using a C8 reverse-phase column, acetonitrile-acetic acid (99.99:0.01, v/v) as mobile phase at 0.8 mL min -1 , oven temperature at 23-25 °C, sample injection volume at 30 μL and detection at 210 nm. The method presented linearity from 10 to 160 μg mL -1 , accuracy, precision, robustness and suitable sensitivity proving to be a useful tool to the obtainment process of lupeol standardized dried extracts of V. ferruginea.Keywords: quality control; triterpene; standardized dried extract.
INTRODUCTIONPharmaceutical companies have a special interest in herbal dried extracts since that its use in pharmaceutical formulations has advantages compared to the powdered plant and conventional fluid forms, such as greater chemical, physical-chemical and microbiological stabilities, easier standardization, higher concentration of active compounds and higher processing capacity in different types of solid dosage forms. 1 However, the chemical complexity inherent to phytopharmaceuticals turns its quality control a complex task. 2 Therefore, the establishment of validated analytical methods plays an important role on the quality assurance of both herbal raw material and intermediate products, 3 allowing at least its standardization on the content of active principles.The Vernonanthura ferruginea (Less.) H. Rob., known as Assapeixe in Brazil, is a plant widely used in folk medicine and it has showed antiulcer activity in preclinical studies. 4 In our laboratory, the same activity was observed to the spray dried extract of V. ferruginea leaves. 5 Despite the pharmacological potential of this plant, efforts to develop a technological product that aims to increase its effectiveness in therapeutic application has been not yet observed.The lupeol is a pentacyclic triterpene commonly found in species of the Asteraceae family, mainly in the typical Vernoniinae. 6,7 It has been known that lupeol has a number of important bioactivities, 8 among them its gastroprotective effect. 9 The lupeol has also been identified as the active principle of Vernonia polyanthes (Less.) antiulcerogenic activity. 10 Although the literature reports several methods for the quantification of lupeol, [11][12][13] no studies of the isolation and quantification of lupeol on the V. ferruginea species have been reported.In order to obtain a standardized dried extract of V. ferruginea, the aims of this work were to isolate a majority compound with an important biological activity to be used as the chemical marker for this species. And then, develop and validate an analytical method for quantitative determination of this compound in V. ferruginea intermediate phytopharmaceutical products.
RESULTS AND DISCUSSION
Isolation and identification of lupeolThe phy...
