resumo
Retama sphaerocarpa is a shrub widely used in traditional medicine. Owing to the huge demand for bioactive natural components, it is fundamental to study in detail the composition of this kind of plants. In this vein, the phenolic fraction of grains and stems from R. sphaerocarpa grown in Algeria was thoroughly investigated by ultra-high-performance liquid chromatography coupled to mass spectrometry (UHPLC-MS). The extracts obtained by methanol:water (50:50) extraction were also evaluated for their antioxidant and antibacterial activities. The UHPLC-MS analysis allowed the identification of forty two compounds, with twenty one identified in grains and twenty six in stems extracts. Thirty one of these components are referenced for the first time as constituents of R. sphaerocarpa. Stems showed to contain a considerably higher amount of phenolic compounds (11.40 g kg(-1) of dry weight). Piscidic acid was identified as the major component, followed by quinic acid and morin/quercetin-di-O-rhamnoside. A taxifolin isomer, isorhamnetin-O-hexoside and an apigenin-6,8-di-C-hexoside isomer were found to be the major phenolic compounds in R. sphaerocarpa grains. The studied samples exhibited moderated antioxidant activities, with stems extract showing the most promising results. This fraction of R. sphaerocarpa also exhibited relevant inhibition against the bacteria Staphylococcus aureus and Pseudomonas aeruginosa. These results are a relevant contribution to the valorization of R. sphaerocarpa as a valuable source of natural bioactive compounds, with recognized nutraceutical applications. (C) 2016 Elsevier B.V. All rights reserved.
palavras-chave
DIFFERENT MORPHOLOGICAL PARTS; HPLC-DAD-ESI/MS; ANTIOXIDANT ACTIVITY; MASS-SPECTROMETRY; MEDICINAL-PLANTS; EXTRACTS; GLYCOSIDES; FLAVONOL; BOISSIER; IDENTIFICATION
categoria
Agriculture
autores
Touati, R; Santos, SAO; Rocha, SM; Belhamel, K; Silvestre, AJD
nossos autores
Armando Jorge Domingues Silvestre
Professor Catedrático
Sónia Andreia Oliveira Santos
Investigador Auxiliaragradecimentos
The authors wish to thank to FCT-Portugal (Fundacao para a Ciencia e Tecnologia) and POPH/FSE for the postdoctoral grants to S. A. O. Santos (SFRH/BPD/84226/2012), for CICECO-Aveiro Institute of Materials, POCI-01-0145-FEDER-007679 (FCT Ref. UID/CTM/50011/2013), and QOPNA research unit (FCT UID/QUI/00062/2013) financed by National Funds through the FCT/MEC and when applicable co-financed by FEDER under the PT2020 Partnership Agreement. R. Touati gratefully acknowledges the financial support as grant from Ministry of Higher Education and Scientific Research of Algeria.