Chemistry and bioactivity of Haplopappus remyanus ("bailahuen"), a chilean medicinal plant

Abstract

A cromatografia do extrato resinoso das partes aéreas de Haplopappus remyanus conduziu ao isolamento do ácido 18-acetoxilabda-7,13E-dien-15-óico, assim como dos derivados monoterpênicos 9-hidróxi-α-terpineol, 9-benzoilóxi-α-terpineol, 7-hidróxi-9-benzoilóxi-α-terpineol e 9-benzoilóxi-(1-formil)-α-terpineol. As estruturas para os novos compostos foram propostas com base em evidências espectroscópicas. A presença de quercetina e de outros cinco flavonóides conhecidos e identificados neste estudo pode ser responsável pela alta atividade antioxidante descrita e pelo moderado efeito tópico anti-inflamatório sobre edema de orelha induzido. Uma avaliação MTT com células tumorais CCRF-CEM mostrou 50% da atividade citotóxica exibida pela doxorubicina nas mesmas condições. Diferenças quantitativas na composição química foram detectadas em comparação com estudos prévios com a mesma espécie, as quais podem ser atribuídas a fatores ambientais.Chromatography on the resinous extract of aerial parts of Haplopappus remyanus led to the isolation of 18-acetoxy-labda-7,13E-dien-15-oic acid along with the monoterpene derivatives 9-hydroxy-α-terpineol, 9-benzoyloxy-α-terpineol,7-hydroxy-9-benzoyloxy-α-terpineol and 9-benzoyloxy-(1-formyl)-α-terpineol. Structures for the new compounds are proposed on spectroscopic evidence. The presence of quercetin and five other known flavonoids identified in this study could account for the reported high antioxidant activity and the moderate topic antiinflammatory effect on induced ear oedema. MTT assay with CCRF-CEM tumor cells showed 50% of the cytotoxic activity displayed by doxorubicin under the same conditions. Quantitative differences in chemical composition were detected in comparison with previous studies of the species that could be attributed to environmental factors.

Anti-Inflammatory Chilean Endemic Plants

“…The natural habitat of this species is limited to the mountainous areas of Chile from the Atacama and Coquimbo regions. Nevertheless, in other regions of Chile, other endemic Haplopappus species, such as H. multifolius Phil., H. remyanus Reiche, and H. taeda Wedd, are all known locally as Bailahuen [ 39 , 122 ]. Regarding H. remyanus anti-inflammatory activity, it has been reported that a dichloromethane extract from fresh leaves exhibits a moderate topical anti-inflammatory effect.…”

“…Regarding H. remyanus anti-inflammatory activity, it has been reported that a dichloromethane extract from fresh leaves exhibits a moderate topical anti-inflammatory effect. The chemical characterization of the studied species showed high levels of flavonoids and coumarins [ 39 ].…”

Absolute Configuration of 18-Acetoxy-Cis-Cleroda-3,13e-Dien-15-Oic Acid

“…All the related Chilean Haplopappus "baylahuen" species produce a resinous exudate with interesting biologically active compounds including, several clerodane and labdane diterpenoids and flavonoids with biological significance 2 . Indeed, the Mapuche medicinal plants Haplopappus multifolius, H. taeda, H. baylahuen and remyanus showed the presence of flavonoids and labdane terpenoids with known antioxidant, choleretic, anti-inflammatory and cholagogue properties 3,4,5 . In the Aymara region, the infusion of H. rigidus has been used to cure or prevent liver diseases, gastro-intestinal disorders, cough and has also been employed as a sexual stimulant attributed to the presence of diterpenoids and flavonoids 1,6,7 .…”