George Gardner's enigmatic species (Gesneriaceae) finally rediscovered.

(Gesneriaceae) was published by George Gardner in 1842, based on material he collected in Serra de Natividade (Tocantins, Brazil) in 1840. The species is now recognized as (Gardner) R.A.

The use of chloroplast genome sequences to solve phylogenetic incongruences in Hook (Orchidaceae Juss).

Background: Current evidence suggests that for more robust estimates of species tree and divergence times, several unlinked genes are required. However, most phylogenetic trees for non-model organisms are based on single sequences or just a few regions, using traditional sequencing methods. Techniques for massive parallel sequencing or next generation sequencing (NGS) are an alternative to traditional methods that allow access to hundreds of DNA regions.

Protective effects of flavonoids and extract from Vellozia kolbekii Alves against oxidative stress induced by hydrogen peroxide in yeast.

Two flavonoids 3,5,7,3',4'-pentahydroxy-6-prenylflavonol (1) and 3,5,7,3',4'-pentahydroxy-8-methyl-6-prenylflavonol (2) were isolated from the ethyl acetate extract of sheaths of Vellozia kolbekii Alves (Velloziaceae). This is the first time that compound 2 has been described. The crude extract and flavonoids were found to be active as 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical scavengers and were able to the increase tolerance of the eukaryotic microorganism Saccharomyces cerevisiae to oxidative stress generated by H(2)O(2).