As sementes de Pterodon pubescens Benth. (Pp), disponíveis comercialmente no Brasil, são utilizadas na medicina popular em preparações anti-inflamatórias, analgésicas e anti-reumáticas. O presente estudo demonstrou as propriedades antinociceptivas da mistura de isômeros 6α-hidroxi-7β-acetoxi-vouacapano-17β-oato de metila e 6α-acetoxi-7β-hidroxi-vouacapano-17β-oato de metila (C1) isolada de Pp, empregando modelos experimentais diferentes. Um estudo de estabilidade foi realizado para investigar a relação da microencapsulação por "spray-drying" na manutenção do efeito antinociceptivo. Para isso, amostras de C1 e extrato de Pp foram monitorados no estudo de estabilidade acelerada, avaliando tanto amostras microencapsuladas como não microencapsuladas. Foi observado que a amostra C1 possui atividade antinociceptiva, revelada pelos ensaios das contorções abdominais e de formalina; foi observada também atividade significativa antialodínica, mas não efeito anti-hiperalgésico. A microencapsulação manteve a atividade e integridade de C1 e do extrato bruto de Pp, demonstrando que a microencapsulação por "spray drying" é uma alternativa útil para aumentar o tempo de prateleira.Pterodon pubescens Benth. (Pp) seeds, commercially available in Brazil, are used in folk medicine in anti-inflammatory, analgesic, and anti-rheumatic preparations. The present study demonstrated the antinociceptive properties of isomers 6α-hydroxy-7β-acetoxy-vouacapan-17β-oate methyl ester and 6α-acetoxy-7β-hydroxy-vouacapan-17β-oate methyl ester (C1), isolated from (Pp), employing different experimental models. A stability study was performed to investigate the relationship of microencapsulation by spray-drying on the maintenance of antinociceptive action. Therefore, C1 and Pp extract samples were monitored in accelerated stability study, evaluating both microencapsulated and non-microencapsulated samples. It was observed that sample C1 possess antinociceptive activity revealed by writhing and formalin tests; C1 showed significantly anti-allodynic, but not antihyperalgesic effect; the microencapsulation maintained the activity and integrity of both, sample C1 and Pp crude extract; microencapsulation by spray drying is a useful alternative to increase shelf life.
Keywords: microcapsules, stability, spray-drying, antinociceptive, Pterodon pubescens
IntroductionPterodon pubescens Benth. (Leguminosae) seeds are commercially available in Brazil. The plant's crude alcoholic extract is used in folk medicine in antiinflammatory, analgesic, and anti-rheumatic preparations. 1,2 Phytochemical studies of Pterodon genus have revealed the presence of alkaloids, isoflavones and diterpenes. Furan diterpenes were identified and isolated from Pterodon species. [3][4][5][6][7] Authors have reported that furanoditerpenes possessing vouacapan skeleton are involved with the anti-inflammatory, antinociceptive and antiproliferative properties of Pterodon pubescens seed crude extract. [7][8][9][10][11][12] We previously reported the antinociceptive properties of geranylgerani...