Metabólitos Secundários e ação antioxidante de Croton helliotripifolius e Croton blanchetianus

Abstract

ResumoAntioxidantes são compostos que reagem com os radicais livres controlando o estresse oxidativo. Muitas doenças estão associadas à produção de radicais livres, os quais tem estimulado investigações do potencial antioxidante de diversas famílias da flora mundial. Essa pesquisa teve como objetivo identificar as principais classes de metabólitos secundários presentes nos estratos etanólicos das folhas de Croton blanchetianus (Marmeleiro) e Croton heliotropiifolius (Velame), e avaliar o seu potencial antioxidante. Os estratos etanólicos foram obtidos das folhas, apresentou um rendimento de 3,29% e 3,26%. Em seguida, os estratos foram submetidos a análise fitoquímica, nos quais foi possível identificar a presença de taninos condensados, flavonoides, flavononas, flavonóis, flavononóis, catequinas e xantonas. A atividade antioxidante dos estratos foi determinada pelo método fotocolorimétrico in vitro realizada por meio do sequestro de radicais livres, usando o DPPH (1,1-difenil-2-picrilhidraliza). Ambos os estratos foram capazes de sequestrar o radical livre DPPH, sendo que o estrato de Croton blanquetianus mostrou ser mais eficiente do que o BHT (Hidroxitolueno butilado; controle positivo), com CE50 = 6,5 ± 0,5 mg mL -1 . Contudo, os resultados observados para os estratos etanólicos, possivelmente sejam atribuídas à presença e a concentração de compostos fenólicos pertencentes as classes dos taninos e flavonoides, os quais foram identificados nesse estudo. Palavras-chave: Radicais livres, fitoquímica, fotocolorimétrico Secondary metabolites and antioxidant action of Croton heliotropiifolius andCroton blanchetianus Abstract Antioxidants are compounds that, at optimal concentrations in relation to oxidable substrates, react with free radicals preventing or reducing oxidative stress. Many diseases and degenerative processes are associated with overproduction of free radicals. This stimulated several research groups to investigate the antioxidant potential of substances produced by several families of the world flora. This study identified the major classes of secondary metabolites present in ethanol leaf extracts of C. blanchetianus (Marmeleiro) and C. heliotropiifolius (Velame), and assessed their antioxidant potential. Ethanol extracts were obtained by the exhaustive extraction method cold and resulted in 3.29% and 3.26% extraction efficiency. Then phytochemical analyses were performed on the extracts to investigate the presence of tannins, flavonoids, flavonones, flavonols, catechins and xanthones. The antioxidant activity of extracts was determined by in vitro photocolorimetric method based on the sequestration of free radicals, using DPPH (1,1-diphenyl-2-picryl-hydrazyl). Both extracts were able to sequestrate DPPH free radical. Croton blanchetianus extract activity showed to be more efficient than BHT (Butylated Hidroxytoluene) (positive control), with EC50 = 6.5 ± 0.5 mg mL -1 . Croton heliotropiifolius extracts showed lower antioxidant activity, with EC50 = 50.15 ± 0.21 but still higher than that observed fo...

Antioxidant and cicatrizing activity of the species Abarema cochliacarpos (Gomes) Barneby J. W. Grimes

“…Polyphenolic compounds comprise a large class of secondary metabolites featuring more than one phenolic ring in their core structure, which is derived from shikimate or polyketide metabolic pathway (Quideau et al, 2011). Their antioxidant mechanisms have been known for some time and relate to the presence of the phenolic ring, which provides the ability to scavenge free radicals and form itself stable free radicals, by hydrogen-atom transfer, or cation radicals, via single-electron transfer (Leopodini et al, 2011;Aquino et al, 2017). The stability of the radical formed is explained by the delocalization of the unpaired electron through the framework of phenolic rings existent in the molecular structure of these secondary metabolites (Quideau et al, 2011;Leopodini et al, 2010).…”

Avaliação do perfil químico e biológico de frutos de Hylocereus polyrhizus

“…Os radicais livres estão associados a diversos processos degenerativos e patogênicos como o envelhecimento, doenças coronarianas, câncer (Degáspari & Waszczynsky, 2004) artrites inflamatórias, úlceras, diabetes, doença de Alzheimer, doença de Parkinson, aterosclerose, entre outros. (Aquino, 2017).…”

Biocultural behavior and traditional practices on the use of species of Euphorbiaceae in rural home gardens of the Semiarid Region of Piauí State (NE, Brazil)

“…For medicinal purposes, a tea with the leaves is prepared as an infusion to treat belly inflammation. The property attributed to the plant to treat inflammations from the leaves may be related to the presence of flavonoids in the vegetative structures of the species (Aquino et al 2017). Concerning its use as fuel, firewood is used directly to prepare food and/or to produce coal.…”

“…Based on that identified knowledge gap, we propose that it is necessary to identify and rescue the traditional knowledge surrounding the ethnobotany of the Euphorbiaceae family in rural home gardens. The registration of local knowledge is essential to conservation, particularly considering that important information and traditional knowledge surrounding the use of plants can face the threat of disappearance (Cajaiba et al 2016). The process of acculturation begins as soon as new generations seek modern means of communication, potentially leading to the loss of this vital relationship between humans and plants, which is traditionally transmitted orally in these communities (Pilla et al 2006).…”