RESUMO
Organic and aqueous solvent extracts of Arctotis auriculata Jacq., Eriocephalus africanus L., Felicia erigeroides DC., and Helichrysum crispum (L.) D. Don, were investigated for selective antimicrobial activities. Organic extracts of A. auriculata and H. crispum inhibited the growth of Mycobacterium smegmatis. The same extracts, together with organic extracts of F. erigeroides, were active against Pseudomonas aeruginosa. Antifungal activities against Candida albicans were exhibited by organic extracts of E. africanus, F. erigeroides, and H. crispum. Organic extracts of A. auriculata and E. africanus, as well as the aqueous extract of the latter plant, were active against Staphyllococcus aureus.
Assuntos
Candida albicans/efeitos dos fármacos , Mycobacterium/efeitos dos fármacos , Extratos Vegetais/farmacologia , Plantas Medicinais , Pseudomonas aeruginosa/efeitos dos fármacos , Staphylococcus aureus/efeitos dos fármacos , Alcaloides/análise , Alcaloides/metabolismo , Candida albicans/crescimento & desenvolvimento , Flavonoides/análise , Flavonoides/metabolismo , Glucosídeos/análise , Glucosídeos/metabolismo , Testes de Sensibilidade Microbiana , Mycobacterium/crescimento & desenvolvimento , Extratos Vegetais/análise , Extratos Vegetais/metabolismo , Folhas de Planta/química , Folhas de Planta/metabolismo , Raízes de Plantas/química , Raízes de Plantas/metabolismo , Caules de Planta/química , Caules de Planta/metabolismo , Plantas Medicinais/química , Plantas Medicinais/metabolismo , Pseudomonas aeruginosa/crescimento & desenvolvimento , Quinonas/análise , Quinonas/metabolismo , Saponinas/análise , Saponinas/metabolismo , Solventes/química , África do Sul , Staphylococcus aureus/crescimento & desenvolvimento , Taninos/análise , Taninos/metabolismo , Triterpenos/análise , Triterpenos/metabolismoRESUMO
Partial acid-hydrolysis of the gum exudates from Hakea sericea and H. gibbosa yields L-arabinose, D-galactose, D-xylose, D-mannose, D-glucuronic acid, the aldobiouronic acid GlcA (beta 1,2)Man, and a dimer of this acid alpha-linked from D-Man to O-4 of GlcA. Methylation analysis showed the modes of linkage of the sugar units to be typical of those present in plant polysaccharide exudates of the arabinogalactan type, while partial acid hydrolysis and Smith degradations established the position of linkage of the peripheral sugar assemblies at O-3 of D-Man in the interior core. Some minor differences were noted between the molecular structures of the gums from these two species of Hakea, the Gal:Ara ratio being higher for H. sericea gum.
