The genus Lychnophora (Asteraceae) is a medicinal plant traditionally used as anti-inflammatory or analgesic agent. Its biological properties have been widely investigated and correlated with its chemical composition, which could be different between the species and even accordingly to the place and season of collection. In this work, it was investigated the spatial and temporal variations in the secondary metabolites from five populations of Lychnophora ericoides. Among them, a more diversified secondary metabolism was observed for the plants collected at Ibiraci-MG (Brazil), a city placed between two biomes, Cerrado and Atlantic Forest. The highest concentrations of chlorogenic acids were found in the Cerrado dry season (winter), while the flavonoids were higher during the rainy season (summer). Significant reduction was observed in the contents of all the secondary metabolites in old leaves, and also in flowery branches. These variations detected in L. ericoides leaves could highly influence the intensity of the biological activities of this plant.

The viability of small-scale heavy-metal waste immobilization into iron phosphate glasses was investigated. Several waste forms containing different amounts of heavy-ion wastes were evaluated (5%, 10%, 15%, 20%, 26%, 33%, 40% and 50% by mass) and their X-ray diffraction patterns revealed that no crystallization occurred in glasses with waste concentrations up to 26%. The dissolution rates for all of the reported glass compositions (ca. 10-8 g cm-2 min-1) are similar to those reported for the materials most commonly used for waste vitrification. Iron phosphate glasses thus proved to be very useful for the immobilization of heavy-metal wastes, exhibiting good contention and chemical durability comparable to that of borosilicate glasses.

This paper describes the antioxidant effects of thirteen phenolic compounds isolated from plants of the genus Lychnophora. Two assays were performed to evaluate these effects: a cellular test that measured the luminol-enhanced chemiluminescence produced by neutrophils stimulated with opsonized zymosan and a cell-free test involving horseradish peroxidase-H2O2-luminol. In both assays, the antioxidant activity of the phenolic compounds was dependent on their concentration and chemical structure. Our results suggest that the ability of phenolic compounds from Lychnophora species to scavenge and inhibit the generation of ROS may be a mechanism underlying the anti-inflammatory activity of extracts from Lychnophora spp.

Eremanthus seidelii MacLeish & Schumacher tem ocorrência restrita ao cerrado, em torno do reservatório de Furnas (MG), em habitats que vêm sendo seriamente deteriorados pela ação humana. A presente investigação fitoquímica mostrou, como metabólitos secundários majoritários das folhas de E. seidelii, as lactonas sesquiterpênicas (LS) 4beta,5-diidro-2',3'-diidroxi-15-desoxi-goiazensolídeo (1) e 4beta,5-diidro-1',2'-epoxi-eremantolídeo-C (2); uma metodologia foi desenvolvida em CLAE para sua análise quantitativa. A análise por CLAE mostrou que não há variações sazonais significativas nas concentrações de ambas LS. Não foram encontradas diferenças qualitativas nos perfis de LS nos indivíduos amostrados. Entretanto, há diferenças no perfil quantitativo entre os indivíduos analisados, apontando para a existência de três quimiotipos quantitativos desta espécie, com diferenças possivelmente originadas na atividade enzimática das enzimas que ciclizam uma LS tipo goiazensolídeo (1) em uma LS tipo eremantolídeo (2).

Eremanthus seidelii MacLeish & Schumacher has a restricted occurrence to the Brazilian "cerrado" surrounding the Furnas (MG) reservoir, in environments that have been seriously damaged by human activity. The present phytochemical investigation reveals that the sesquiterpene lactones (SL) 4beta,5-dihydro-2',3'-dihydroxy-15-desoxy-goyazensolide (1) and 4beta,5-dihydro-1',2'-epoxy-eremantholide-C (2) are the major secondary metabolites in E. seidelii leaves, and an HPLC method was developed for their quantitative analysis. HPLC analysis showed no significant seasonal variation in the concentrations of both SL. No qualitative differences were found in the SL patterns of all individuals sampled. However, there is a different SL quantitative pattern among the plants analyzed, pointing to the existence of three quantitative chemotypes of this species, with differences possibly originating from the activity of the enzymes that cyclize the goyazensolide type SL (1) to a eremantholide type SL (2).