New ent-kaurene-type nor-diterpene and other compounds isolated from Annona vepretorum Mart. (Annonaceae).

A new nor-ent-kaurene diterpene and ten other compounds were isolated from Annona vepretorum stems, including four kaurene diterpenes, three alkamides, one sesquiterpene and two steroids. Their chemical structures were elucidated using spectroscopic methods, including 1D-, 2D-NMR, and HRESIMS. The absolute configuration of compounds 1, 5, 8, 9 and 10 was confirmed by CD experiments. Compounds 1-5 and 8-10 were evaluated for cytotoxic activity using (3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide) MTT method, against three human carcinoma cell lines: human colon (HCT-116), glioblastoma (SF295) and prostate (PC3). However, all isolated compounds exhibited low cytotoxic activity.

Induction, biochemical trait and phytochemical screening of calluses of Amburana cearensis (Allemão) A. C. Smith

Amburana cearensisis an arboreal legume of the Fabaceaefamily,with high phytotherapic and medicinal potential due the presence of secondary metabolites. The objective of this study was to evaluate the effect of 2,4-dichlorophenoxyacetic acid (2,4-D) and 4-amino-2,5,6-trichloro-2-pyridinecarboxylic acid (picloram) on the in vitroinduction of callogenesis of A. cearensisand analyze the biochemical and phytochemical potential of these calluses. For callus induction, leaf and cotyledon segments were used as explants, which were inoculated in woody plant medium (WPM) supplemented with different concentrations of 2,4-D (0, 5, 10, 20, 40 μM) or picloram (0, 5, 10, 20, 40, 80 μM). The callus growth curve was estimated based on fresh weight, measured at 7-day intervals until 28 days after inoculation. The calluses were analyzed by biochemical tests to quantify the reducing sugars and total proteins. Phytochemical screening and high-performance liquid chromatography were performed to establish the phytochemical profile of extracts from calluses. The concentrations of 21.94 μMand 26.46 μMof 2,4-Dinduced the greatest formation of compact and friable calluses from the leaf and cotyledon segments, respectively. The growth curve had two distinct phases(lag and exponential) for both types of calluses evaluated. The maximum levels of reducing sugars and total proteins in the calluses from leaf and cotyledon segments were obtained on the day of inoculation and after 28 days of cultivation, respectively. The results of the phytochemical analysis identified the presence of coumarin in all the extracts evaluated, this secondary metabolite has high pharmacological potential.

Fenóis totais, flavonoides totais e atividade antioxidante de Selaginella convoluta (Arn. ) Spring (Selaginellaceae) / Total phenols, total flavonoids and antioxidant activity of Selaginella convoluta (Arn. ) Spring (Selaginellaceae)

Selaginella convoluta é uma espécie conhecida no Nordeste do Brasil como “jericó”, e bastante utilizada na medicina popular para tratamento de doenças. Este estudo teve como objetivo determinar o teor de compostos fenólicos e avaliar a atividade antioxidante in vitro do extrato etanólico e das frações obtidas por partição de S. convoluta. O conteúdo de fenóis totais foi determinado pelo método de Folin-Ciocalteu. O teor de flavonoides totais também foi avaliado. A atividade antioxidante dos extratos foi avaliada usando o método do sequestro do radical DPPH e inibição da auto-oxidação do sistema β-caroteno-ácido linoleico e comparada com os compostos de referência ácido ascórbico, BHA, BHT, quercetina e pirogalol. O conteúdo fenólico total foi de 209,90 ± 19,84 e 61,13 ± 2,50 mg equivalente de ácido gálico/g para os extratos AcOEt e EEB, respectivamente. O conteúdo de flavonoides totais foi de 155,70 ± 6,21 e 62,13 ± 4,10 para os dois extratos, respectivamente. Os extratos AcOEt e EEB apresentaram boas atividades antioxidantes. BHA foi o antioxidante mais efetivo, com um valor de IC50 de 1,62 ± 0,69 μg/mL. Os resultados obtidos mostram que S. convoluta pode ser uma boa fonte de compostos fenólicos antioxidantes. Estudos posteriores serão realizados para se chegar ao isolamento e identificação dos principais constituintes fenólicos dos extratos.

Selaginella convoluta is a species of "spike moss" (an order of pteridophytes) known in Northeast Brazil as "jericó" and widely used in popular medicine to treat several diseases. Phenolic compounds were determined in extracts of whole Selaginella convoluta plants. The total phenolics content was determined by the Folin-Ciocalteu method. Total flavonoid content was also measured. Antioxidant activities of the extracts were assayed by DPPH radical scavenging and inhibition of β-carotene-linoleic acid bleaching and compared with ascorbic acid, BHA, BHT, quercetin and pyrogallol, used as reference compounds. The total phenolics contents of ethyl acetate (EtOAc) and crude ethanol extract (CEE) were 209.90 ± 19.84 and 61.13 ± 2.50 mg of gallic acid equivalent/g, respectively. The total flavonoids contents were 155.70 ± 6.21 and 62.13 ± 4.10 mg of catechin equivalent/g for the two extracts, respectively. The EtOAc and CEE extracts exhibited good antioxidant activities. BHA was the most effective antioxidant, with an IC50 of 1.62 ± 0.69 μg/ml. The results show that S. convoluta could be a good source of antioxidant phenolics. Further research will be carried out to achieve the isolation and identification of the main phenolic constituents of the extracts.