Antioxidant activities and triterpenoids isolated from Alternanthera brasiliana (L.) Kuntze leaves

作者：Pereira D F; Zanon R B; dos Santos M; Boligon A A; Athayde M L^*

来源：Natural Product Research, 2013, 27(18): 1660-1663.

DOI：10.1080/14786419.2012.750313

• Alternanthera brasiliana
• antioxidant capacity
• 1
• 1-diphenyl-2-picrylhydrazyl
• steroids
• total phenolics

The species Alternanthera brasiliana (L.) Kuntze (Amaranthaceae) is a perennial herbaceous plant widely distributed in Brazil's eastern beaches and certain Amazonian regions. Crude ethanolic (70%) extract, fractions (dichloromethane, ethyl acetate and n-butanolic) and the mixture isolated were investigated regarding their content of total phenolic compounds by Folin-Ciocalteau assay. Total phenolic contents varied from 29.0 to 56.6mg/g (dry fraction). The scavenging capacity of the extract, fractions and mixture isolated was characterised by the 1,1-diphenyl-2-picrylhydrazyl method. Only ethyl acetate fraction exhibited a modest scavenging capacity (SC50=163.00g/mL and SC% =64.29% at 250g/mL) in a dose-dependent manner. Crude extract, dichloromethane and butanolic fractions presented a very weak scavenging capacity (SC% 40% at 250g/mL). A correlation between the antioxidant activity and the total phenolic contents could not be observed. The fractionation and purification of dichloromethane fraction evidenced the presence of a mixture of -sitosterol, stigmasterol and spinasterol, which was identified by NMR methods and compared with literature data. Results of this study demonstrated for the first time the antioxidant activity of A. brasiliana.

• 出版日期2013-9-1