Volume 65, March 2015, Pages 198–202
Antioxidant activity and verbascoside content in extracts from two uninvestigated endemic Plantago spp
Highlights
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- The antioxidant activity of endemic Portuguese species Plantago algarbiensis Samp. and Plantago almogravensis Franco was higher than that of P. lagopus.
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- LC–DAD analyses indicate verbascoside as a major component of all extracts studied.
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- In vitro cultures of P. algarbiensis showed the highest verbascoside content.
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- High correlation was found between antioxidant activity and total phenolic content.
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- No correlation was observed between antioxidant activity and verbascoside content.
Abstract
This work describes for the first time the antioxidant activity of extracts from wild plants and in vitro cultures of two previously uninvestigated Plantago spp. endemic to Portugal, Plantago algarbiensis Samp. and Plantago almogravensis Franco. The well-known and widely distributed species Plantago lagopus
L. was also studied for comparison. Although the extracts from the
three species exhibited radical scavenging and iron-reducing properties,
the extracts from the two endemic species showed greater activity
irrespectively of plant material source. Both P. algarbiensis extracts showed similar antioxidant activity whereas, in the case of P. almogravensis higher activity was observed for extracts from wild plants compared to extracts from in vitro
cultures. Liquid chromatography–diode array detection analyses indicate
verbascoside as a major constituent of all extracts and the highest
content was obtained from in vitro cultures of P. algarbiensis.
In addition, a high correlation between the antioxidant activity
measured with three methods and the total phenolic content was found,
but no correlation was observed between antioxidant activity and
verbascoside content. The results suggest that P. algarbiensis and P. almogravensis are sources of health-beneficial phytochemicals and indicate that in vitro cultures represent a promising alternative for the biosynthesis of verbascoside.
Abbreviations
- ABTS, 2,2′-azinobis(3-ethylbenzothiazoline-6-sulphonic acid);
- DPPH, 2,2-diphenyl-1-picrylhydrazyl;
- F–C reagent, Folin–Ciocalteu reagent;
- GAE, gallic acid equivalents;
- LC–DAD, liquid chromatography–diode array detection;
- TCA, trichloroacetic acid;
- TE, trolox equivalents;
- TEAC, trolox equivalent absorbance capacity;
- Trolox, 6-hydroxy-2,5,7,8-tetramethylchroman-2-carboxylic acid
Keywords
- Endemic species;
- Liquid chromatography–diode array detection;
- Phenolics;
- Radical scavenging;
- Reducing power;
- Verbascoside
- Corresponding author. Tel.:
+351 289800910; fax: +351 289818419.
Copyright © 2014 Published by Elsevier B.V.
