This study was carried out to evaluate the antinociceptive effects of ethanolic extract from Neoglaziovia variegata (Nv-EtOH) in mice using models of nociception. The evaluation of antinociceptive activity was carried out by the acetic acid-induced writhing, formalin and hot plate tests. HPLC was used to determine the fingerprint chromatogram of the Nv-EtOH. In the acetic acid-induced writhing test, the Nv-EtOH (100, 200 and 400 mg/kg, i.p.) reduced the number of writhing by 89.50, 71.34 and 87.42%, respectively. Additionally, the extract decreased by 46.67, 44.23 and 41.81%, respectively, the paw licking time in the first phase of the formalin test, as well as 70.14, 69.43 and 90.28%, respectively, in the second phase of this test. In the hot plate test, Nv-EtOH increased the reaction time when compared to control group. The effects of Nv-EtOH and morphine in the formalin and hot plate tests were antagonized by naloxone. The presence of phenolic compounds in the extract was confirmed using HPLC. Results based from formalin and hot plate tests indicated that the extract has compounds that interact with the opioid system. The effect of Nv-EtOH on hot plate response provides a confirmation of its central effect. Pharmacological and chemical studies are continuing in order to characterize the mechanism responsible for this effect.

The photoprotective activity of flowers and antibacterial activity of the leaves of Neoglaziovia variegata were investigated. This study also identified the first phenolic compounds of the extracts and fractions of this species by high performance liquid chromatography (HPLC). The photoprotective activity was measured using the spectrophotometric method. The antibacterial activity was evaluated by microdilution method. The chromatographic analysis was performed in HPLC coupled with iode array detector (DAD) detector, using wavelengths of 254 and 320 nm. Nv-Fl-EtOH, Nv-Fl-CHCl 3 and Nv-Fl-AcOEt showed characteristic absorption bands in regions UVB and UVA in a concentration-dependent manner. Nv-Fl-CHCl 3 presented the highest sun protection factor (11.45 ± 2.87). Extracts from the leaves showed activity against most of the microorganisms tested, especially Bacillus cereus, Escherichia coli, Salmonella enterica, Serratia marcescens and Shigella flexneri. HPLC analysis revealed the presence of six phenolics: two flavonoids (isoquercetin and kaempferol-3-O-rhamnoside) and four phenolic acids (caffeic, protocatechuic, p-coumaric and vanillic acids). This result justifies the biological properties, that the species has demonstrated and can lead other phytochemical studies aiming the isolation of these compounds.