BackgroundEssential oil obtained from rhizomes of the Zingiber zerumbet (L.) Smith (popularly known in Brazil as bitter ginger) is mainly constituted by the biomolecule zerumbone, which exhibit untapped antimicrobial potential. The aim of this study was to investigate the antimicrobial activity of the zerumbone from bitter ginger rhizomes against the cariogenic agent Streptococcus mutans.MethodsFirstly, the essential oil from rhizomes of Zingiber zerumbet (L.) Smith extracted by hydrodistillation was submitted to purification and recrystallization process to obtain the zerumbone compound. The purity of zerumbone was determined through high-performance liquid chromatography analysis. Different concentrations of zerumbone were tested against the standard strain S. mutans (ATCC 35668) by using microdilution method. The speed of cidal activity was determined through a time kill-curve assay. The biological cytotoxicity activity of zerumbone was assessed using Vero cell line through MTT assay.ResultsThe zerumbone showed a minimum inhibitory concentration (MIC) of 250 μg/mL and a minimum bactericidal concentration (MBC) of 500 μg/mL against S. mutans. After six hours of bacteria-zerumbone interaction, all concentrations tested starts to kill the bacteria and all bacteria were killed between 48 and 72 h period at the concentration of 500 μg/mL (99,99% of bacteria were killed in comparison with original inoculum). In addition, zerumbone showed no cytotoxicity activity on mammalian continuous cells line.ConclusionsThese results draw attention to the potential of zerumbone as antimicrobial agent against S. mutans infection, indicating its possible use in the phyto-pharmaceutical formulations as new approach to prevent and treat tooth decay disease.Electronic supplementary materialThe online version of this article (10.1186/s12906-018-2360-0) contains supplementary material, which is available to authorized users.

Background: Essential oil obtained from rhizomes of the Zingiber zerumbet (L.) Smith (popularly known in Brazil

The present work concerns the analgesic effects of zerumbona, obtained from Zingiber zerumbet L. Smith cultivated in Manaus/Amazonas. The compound has been studied for decades because it has potent cytotoxic activity against liver and prostate tumor cells, colon, and breast. The plant is rich in sesquiterpenes, glycosylated flavonoids that present important pharmacological activities; standing out cytotoxic activity against neoplastic cells of cancers. The objective of this study was to test the antinociceptive activity of zerumbone (ZER) using chemical and thermal nociception models, that is, writhing test induced by acetic acid and hot plate test. ZER administered orally and intraperitoneally produced significant and dose-dependent analgesic activity against the pain, acetic acid, formalin, and capsaicin models. In addition, ZER significantly increased the dormancy of the animals in the hotplate test pain model (49-540C). It was demonstrated that intraperitoneal (i.p.) and oral (p.o.) administration of ZER sesquiterpene in doses of 150 to 500 mg/kg i.p. and 250 to 1500 mg/kg p.o. produced significant dose-dependent inhibition of acetic acid-induced abdominal writhing, as compared to fentanest (20 µg/kg). At the same intraperitoneally and orally doses, the ZER produced significant dose-dependent latency-time increases in the hot-plate test relative to control. It was concluded that ZER exhibits both central and peripheral antinociceptive activity, indicating it to hold therapeutic potential for the discovery of new antinociceptive drugs as an alternative for the discovery of new drugs in the control of neurogenesi. The ZER exhibited similar efficacy and strength via both oral and intraperitoneally routes. ZER is the major essential oil component, a new sesquiterpene responsible for its nociceptive effect, when compared with other antinociceptive sesquiterpenes described in literature.