RESUMO
Over 15 years, with the support of a Canadian funding agency, the Universidad Mayor de San Simón, in Bolivia, undertook a large survey of aromatic plants of the South American country. More than a hundred species were studied under various aspects, including the production and characterization of essential oils. As part of this survey, the chemical composition of an essential oil sample obtained from Pentacalia herzogii (Asteraceae) growing wild in the High Valley region of the department of Cochabamba was determined by a combination of GC and GC-MS measurements. α-Pinene was the main constituent of this essential oil (34%), accompanied by limonene (22%) and germacrene D (7.5%) as well as an important fraction of methoxylated monoterpenoids. They were mainly isomers of thymol methyl ether, accounting for 13% of the chromatogram. A new quantitatively important compound (9%) was identified through NMR and chemical synthesis as 4-isopropyl-6-methylbenzo[d][1,3]dioxole, and designated herzogole, alongside the minor related compound 1-isopropyl-2,3-dimethoxy-5-methylbenzene. The monoterpene benzodioxole featured a distinctive green-phenolic aroma which could raise interest for fragrance use. Since these compounds were not known naturally, a biosynthetic mechanism of their formation was proposed and put in perspective to illustrate the metabolic originality of P. herzogii.
Assuntos
Asteraceae/química , Benzodioxóis/isolamento & purificação , Óleos Voláteis/análise , Monoterpenos Bicíclicos/isolamento & purificação , Cromatografia Gasosa-Espectrometria de Massas , Limoneno/isolamento & purificação , Monoterpenos/isolamento & purificação , Óleos Voláteis/química , Componentes Aéreos da Planta/química , Óleos de Plantas/análise , Óleos de Plantas/química , Sesquiterpenos de Germacrano/isolamento & purificaçãoRESUMO
ETHNOPHARMACOLOGY RELEVANCE: Agastache mexicana is a popular plant of great demand in folk medicine, essentially due to its calming properties and for alleviating arthritic, muscular and abdominal pain. Despite its spectrum for pain relief, pharmacological studies of its bioactive constituents have been barely investigated. AIM OF THE STUDY: To evaluate protective properties of the A. mexicana and bioactive compounds improving pathological gastrointestinal conditions in rodents. MATERIAL AND METHODS: Different doses of the essential oil of A. mexicana ssp. mexicana and ssp. xolocotziana (30-562.2 mg/kg, i.p.) and individual monoterpenes (3-300 mg/kg, i.p.) were evaluated in an abdominal pain model. The most active monoterpene limonene and sulfasalazine (reference drug, 100 mg/kg, p.o.) were also evaluated in the oxazolone-induced colitis model using an oral gavage, where some inflammatory cytokines were analyzed by enzyme-linked immunosorbent assays. Finally, colonic histological assessment and gastroprotection in the absolute ethanol-induced ulcer model were explored. RESULTS: Our results demonstrated that the essential oil of both subspecies produced a significant reduction in the abdominal writhes, where monoterpenes limonene and pulegone were partially responsible bioactive metabolites. Limonene showed the major antinociceptive efficacy in the writhing test. It also significantly decreased hyperalgesia, pathological biomarkers, and colonic inflammatory cytokines in the oxazolone-induced colitis model, as well as prevention in gastric damage. CONCLUSIONS: Present results provide scientific evidence to reinforce the use of A. mexicana in the traditional medicine for gastrointestinal conditions, mainly related to pain and inflammation, demonstrating the potential of monoterpenes as natural products in the therapeutics of gastrointestinal affections such as ulcer, colitis, and abdominal pain.
Assuntos
Agastache/química , Analgésicos/farmacologia , Monoterpenos/farmacologia , Óleos Voláteis/farmacologia , Analgésicos/química , Analgésicos/isolamento & purificação , Animais , Colite Ulcerativa/tratamento farmacológico , Modelos Animais de Doenças , Relação Dose-Resposta a Droga , Fármacos Gastrointestinais/administração & dosagem , Fármacos Gastrointestinais/isolamento & purificação , Fármacos Gastrointestinais/farmacologia , Limoneno/administração & dosagem , Limoneno/isolamento & purificação , Limoneno/farmacologia , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Monoterpenos/química , Monoterpenos/isolamento & purificação , Óleos Voláteis/química , Óleos Voláteis/isolamento & purificação , Dor/tratamento farmacológico , Ratos , Ratos Wistar , Sulfassalazina/farmacologiaRESUMO
The ethnobotanical uses of Brazilian plants for different injuries and diseases conjoined with local rich biodiversity represent an important resource for research and development. This study aimed to characterise BDEO and its in vitro activity on the third instar larvae (L3) of Cochliomyia macellaria. Groups of 20 L3 were placed on filter paper impregnated with increasing concentrations of 5-30% (v/v), equivalent to 0.79-4.77 µL/cm2, solubilised in ethanol or acetone. The major constituents of BDEO were ß-pinene (9.94%), D-limonene (9.59%), ß-nerolidol (7.93%), caryophyllene (7.69%), spathulenol (6.69), α-muurolene (6.74%) and α-pinene (5.31%). Lethal concentrations of 50% for BDEO on C. macellaria (LC50) after 24 and 48 h of exposure were 2.63 and 2.47 µL/cm2 for ethanol and 9.58 and 8.11 µL/cm2 for acetone, respectively. Furthermore, larvae cuticle abnormalities and adult deformity were observed. Our data confirm the effectiveness of BDEO as an ecofriendly product against blowflies.