Antioxidant capacity of four polyphenol-rich Amazonian plant extracts: A correlation study using chemical and biological in vitro assays (original) (raw)

Antioxidant activity of five Brazilian plants used as traditional medicines and food in Brazil

Background: This study evaluates the radical-scavenging activity of five plants used as food and medicines in the northeastern region of Brazil. Materials and Methods: Spectrophotometric analysis of the plants’ ethanol extracts was carried out. The antioxidant activity was determined by the DPPH (2,2-diphenyl-1 picrylhydrazyl) test. The antioxidant capacity was measured using ascorbic acid as a positive control. Results: All tested plant extracts showed an antioxidant activity, but the highest activity was observed with the extracts of Momordica charantia and Eugenia jambolana. Conclusions: Therefore, these species must be studied as a putative source of products for use in the prevention and treatment of diseases in which oxidants or free radicals are implicated.

Phenolic composition, antioxidant and anti-proliferative activities of edible and medicinal plants from the Peruvian Amazon

Among 23 extracts of medicinal and edible plants tested, Mauritia flexuosa L.f., Arecaceae, showed significant antioxidant ability (DPPH and ORAC = 1062.9 and 645.9 ± 51.4 g TE/mg extract, respectively), while Annona montana Macfad., Annonaceae, demonstrated the most promising anti-proliferative effect (IC 50 for Hep-G2 and HT-29 = 2.7 and 9.0 g/ml, respectively). However, combinatory antioxidant/anti-proliferative effect was only detected in Oenocarpus bataua Mart., Arecaceae (DPPH = 903.8 and ORAC = 1024 g TE/mg extract; IC 50 for Hep-G2 and HT-29 at 102.6 and 38.8 g/ml, respectively) and Inga edulis Mart., Fabaceae (DPPH = 337.0 and ORAC = 795.7 g TE/mg extract; IC 50 for Hep-G2 and HT-29 at 36.3 and 57.9 g/ml, respectively). Phenolic content was positively correlated with antioxidant potential, however not with anti-proliferative effect. None of these extracts possessed toxicity towards normal foetal lung cells, suggesting their possible use in development of novel plant-based agents with preventive and/or therapeutic action against oxidative stress-related diseases.

www.mdpi.com/journal/ijms Lipid Oxidation Inhibitory Effects and Phenolic Composition of Aqueous Extracts from Medicinal Plants of Colombian Amazonia

2012

Abstract: Diverse plants of ethnobotanic interest in Amazonia are commonly used in traditional medicine. We determined the antioxidant potential against lipid peroxidation, the antimicrobial activity, and the polyphenol composition of several Amazonian plants (Brownea rosademonte, Piper glandulosissimum, Piper krukoffii, Piper putumayoense, Solanum grandiflorum, and Vismia baccifera). Extracts from the plant leaf, bark, and stem were prepared as aqueous infusions, as used in folk medicine, and added to rat liver microsomes exposed to iron. The polyphenolic composition was detected by reverse-phase HPLC coupled to diode-array detector and MS/MS analysis. The antimicrobial activity was tested by the spot-on-a-lawn method against several indicator microorganisms. All the extracts inhibited lipid oxidation, except the P. glandulosissimum stem. The plant extracts exhibiting high antioxidant potential (V. baccifera and B. rosademonte) contained high levels of flavanols (particularly, cate...