| 1. |
- Gouveia-Figueira, Sandra C., 1984-, et al.
(författare)
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Phenolic screening by HPLC-DAD-ESI/MSn and antioxidant capacity of leaves, flowers and berries of Rubus grandifolius Lowe
- 2015
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Ingår i: Industrial crops and products (Print). - : Elsevier. - 0926-6690 .- 1872-633X. ; 73, s. 28-40
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Tidskriftsartikel (refereegranskat)abstract
- In Madeira Island (Macaronesia Island), Rubus grandifolius Lowe berries, locally known by amoras, are widely consumed fresh or processed as jam, juice or liquor. Folk medicine describes R. grandifolius Lowe fruits and leaves being used to treat diabetes, as depurative, diuretic and to relieve sore throat. The aim of this study was to investigate phenolic composition and antioxidant capacity of the different edible parts of the plant (berries, leaves and flowers). HPLC-DAD-ESI/MSn was used to establish the phenolic profile. Phenolic monomers such as flavonol O-glycosilated (quercetin and kaempferol), quinic acid and caffeic acid conjugates were characterized using the electrospray source in the negative mode; while positive mode was employed to detect glycosylated anthocyanins (cyanidin, delphinin and petunidin). The berries presented a higher radical scavenger capacity (DPPH and ABTS assays) and reducing properties (FRAP) than the leaves and the flowers. Ethanolic extracts showed highest antioxidant capacity when compared with water based extracts: DPPH values of 147.9 +/- 0.7 mu mol eq Trolox/g DM; ABTS value of 255.8 +/- 1.9 mu mol-eq Trolox/g DM and FRAP value 9455 +/- 29 mmol Fe(II)/mgDM). (C) 2015 Elsevier B.V. All rights reserved.
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| 2. |
- Llorent-Martinez, Eulogio J., et al.
(författare)
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HPLC-ESI-MSn characterization of phenolic compounds, terpenoid saponins, and other minor compounds in Bituminaria bituminosa
- 2015
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Ingår i: Industrial crops and products (Print). - : Elsevier BV. - 0926-6690 .- 1872-633X. ; 69, s. 80-90
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Tidskriftsartikel (refereegranskat)abstract
- Bituminaria bituminosa is a wild legume that can endure drastic conditions, including contaminated and degraded soils. It has been traditionally used as feeding for livestock, and different uses in folk medicine are known. The chemical composition of leaves and flowers from B. bituminosa is presented for the first time. The screening of phytochemical compounds was carried out using high-performance liquid chromatography with electrospray ionization mass spectrometric detection (HPLC-ESI-MSn). More than 40 compounds were identified or tentatively characterized. A high percentage of the detected compounds corresponded to glycosylated flavonoids, especially from apigenin, although phenolic acids, lignans, and saponins were also identified.
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| 3. |
- Spinola, Vitor, et al.
(författare)
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Ulex europaeus : from noxious weed to source of valuable isoflavones and flavanones
- 2016
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Ingår i: Industrial crops and products (Print). - : Elsevier BV. - 0926-6690 .- 1872-633X. ; 90, s. 9-27
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Tidskriftsartikel (refereegranskat)abstract
- The screening and quantification of the main phenolic compounds in leaves and flowers of Ulex europaeus (gorse) was carried out by high-performance liquid chromatography with electrospray ionization mass spectrometric detection (HPLC-ESI-MSn) after ultrasound-assisted extraction with methanol. About 98% of compounds corresponded to flavonoids, distributed as flavonols, flavones, isoflavones and flavanones. Flavonols were mainly quercetin glucosides; most of the found flavones were apigenin derivatives and the isoflavone group was dominated by glycitin. The flavanone group was composed mainly of liquiritigenin derivatives, substances usually found in liquorice (Glycyrrhiza ssp) and associated with high pharmacological relevance; in Ulex they represent about 25% of total polyphenols content. Phenolic acids and saponins were also detected, as minor components. In vitro antioxidant activity (nitric oxide, superoxide assays, ABTS and DPPH assays) of leaves and flowers, and their inhibitory effects towards digestive enzymes related to carbohydrate metabolism (alpha-glucosidase and alpha-amylase) were also studied.
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