ABSTRACT
ABSTRACT In this study, a comprehensive phytochemical characterization of two morphologically related species from the genus Espeletia Mutis ex Bonpl., namely, Espeletia grandiflora Humb. & Bonpl. and Espeletia killipii Cuatrec., Asteraceae, has been performed by gas chromatography coupled to flame ionization detection, gas chromatography coupled to mass spectrometry and ultra-high performance liquid chromatography coupled to ultraviolet and high-resolution mass spectrometry. Analysis of ethanol extracts (70%, v/v) from leaves and concomitant compound dereplication allowed the identification of major peaks, most of them new reports for the genus Espeletia or the subtribe Espeletiinae. Chemical characterization of resins essential oils indicated several similarities and differences between both species and from other members of the subtribe. Chemometric analysis (hierarchical clustering analysis and orthogonal partial least-squares discriminant analysis) applied to the essential oil composition of 31 species from Espeletiinae furthermore allowed the identification of three primary clusters correlated with the taxonomy. Hence, this study underscored qualitative and semiquantitative differences between the chemical composition of leaves and resins of E. grandiflora and E. killipii, provided information on chemotaxonomy and described the presence of different trends in the essential oil composition from species of Espeletiinae.
ABSTRACT
Abstract The tagitinins isolated of Tithonia diversifolia (Hemsl.) A. Gray, Asteraceae, are the most studied sesquiterpene lactones due to their wide spectrum of pharmacologic activities, especially related with nuclear factor-kappa B inhibition. Nevertheless, detailed studies about the mechanism of action of its active compounds are still lacking. Neutrophils perform a fundamental role in the inflammatory response to several etiologic factors. However, the effect of tagitinins on human neutrophil is not yet clearly known. We investigated the role of tagitinin C (1), tagitinin F (2) and tagitinin A (3) in activation and survival of human neutrophils to establish possible effects in their mechanisms of inflammation. Human neutrophils were purified from the peripheral blood and cultivated with tagitinins C (1), F (2) and A (3) in the presence or not of Escherichia coli lipopolysaccharide. The enzymatic activity, apoptosis and secretion of cytokines rate were determined after 18 h. Lipopolysaccharide-induced myeloperoxidase activity of human neutrophils was significantly inhibited only by tagitinin F (2). Apoptosis of neutrophils was increased in the presence of tagitinin C (1), and it occurred independently of the presence of lipopolysaccharide or dexamethasone. Tagitinins C (1), F (2) and A (3) decrease lipopolysaccharide-induced interleukin-6, interleukin-8 and Tumor necrosis factor alpha production by human neutrophils. Together, these results indicate that tagitinins exhibit anti-inflammatory action on human neutrophils. However, tagitinin F (2) was the only sesquiterpene lactone that decreased secretion of inflammatory products by neutrophils without inducing neutrophil apoptosis.
ABSTRACT
The total flavonoid content (TFC), total polyphenols content (TPC), and in vitro antioxidant activity (AA) of six Bidens pilosa L., Asteraceae, populations harvested from different localities were evaluated in this work. The plants were separated in roots, stems, and leaves/flowers, and the influence of extraction methods was investigated.Areversed-phase high-performance liquid chromatography method (HPLC) was developed and employed to obtain characteristic HPLC fingerprints of the bioactive compounds present in the extractive solutions, which were correlated with the TFC, TPC, and AA. Extractive solutions of leaves/flowers presented a higher AA when compared with those obtained from other parts of the plant (IC50 of 35.35±0.10 µg/mL). The stem extracts presented the lowest AA (IC50 117.2±1.96 µg/mL). A direct correlation of AA with TFC and TPC was evidenced. The highest AA was obtained by dynamic maceration and was statistically different from the AA presented by the extractive solutions obtained by other extraction methods. The results of this work evidenced differences that can be found at different stages of development of phytopharmaceutical preparations from B. pilosa and highlighted the importance of using the concentration of marker compounds as well as HPLC fingerprints as quality control parameters.