<?xml version="1.0" encoding="UTF-8"?><xml><records><record><source-app name="Biblio" version="7.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">El Omari, Bouchra</style></author><author><style face="normal" font="default" size="100%">Fleck, Isabel</style></author><author><style face="normal" font="default" size="100%">Aranda, Xavier</style></author><author><style face="normal" font="default" size="100%">Abadía, Anunciación</style></author><author><style face="normal" font="default" size="100%">Cano, Antonio</style></author><author><style face="normal" font="default" size="100%">Arnao, Marino B</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Total antioxidant activity in Quercus ilex resprouts after fire</style></title><secondary-title><style face="normal" font="default" size="100%">Plant Physiology and Biochemistry</style></secondary-title></titles><keywords><keyword><style  face="normal" font="default" size="100%">carotenoids</style></keyword><keyword><style  face="normal" font="default" size="100%">non-photochemical quenching</style></keyword><keyword><style  face="normal" font="default" size="100%">Quercus ilex</style></keyword><keyword><style  face="normal" font="default" size="100%">reactive oxygen species</style></keyword><keyword><style  face="normal" font="default" size="100%">Resprouts</style></keyword><keyword><style  face="normal" font="default" size="100%">total antioxidant activity</style></keyword></keywords><dates><year><style  face="normal" font="default" size="100%">2003</style></year></dates><volume><style face="normal" font="default" size="100%">41</style></volume><pages><style face="normal" font="default" size="100%">41-47</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">After ﬁre, holm oak (Quercus ilex L.) resprouts have a higher light availability and photosynthetic activity than control plants in intact vegetation. To assess the differences in protection between these plants, we determined, in two forests, changes in gas-exchange rates, chlorophyll ﬂuorescence parameters, chloroplast pigment content and total antioxidant activity (TAA) in different seasons, at different times of the day and in relation to leaf age. The end-point method used for TAA determination allowed the evaluation of the relative contribution of hydrophilic and lipophilic antioxidants in leaf extracts. High correlations were obtained between lipophilic TAA and certain chloroplast pigment content, the highest contribution being provided by b-carotene and the components of the xanthophyll cycle (zeaxanthin + antheraxanthin, violaxanthin). All leaves showed a much higher contribution (94–99%) of hydrophilic than lipophilic antioxidants to TAA. In summer, at midday, photosynthetic rates and TAA were higher in resprouts. In these plants, reduced xanthophyll-cycle participation (as shown by non-photochemical quenching (NPQ) and xanthophyll pool content) was compensated by an increased participation of hydrophilic antioxidants. No effect of time of day or plant age was observed. The results suggest that energy dissipation as heat, and detoxiﬁcation mechanisms contribute to the protective strategies of control plants and resprouts, albeit to a different extent.</style></abstract></record><record><source-app name="Biblio" version="7.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">El Omari, Bouchra</style></author><author><style face="normal" font="default" size="100%">Fleck, Isabel</style></author><author><style face="normal" font="default" size="100%">Aranda, Xavier</style></author><author><style face="normal" font="default" size="100%">Abadía, Anunciación</style></author><author><style face="normal" font="default" size="100%">Cano, Antonio</style></author><author><style face="normal" font="default" size="100%">Arnao, Marino B.</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Total antioxidant activity in Quercus ilex resprouts after fire</style></title><secondary-title><style face="normal" font="default" size="100%">Plant Physiology and Biochemistry</style></secondary-title></titles><keywords><keyword><style  face="normal" font="default" size="100%">carotenoids</style></keyword><keyword><style  face="normal" font="default" size="100%">non-photochemical quenching</style></keyword><keyword><style  face="normal" font="default" size="100%">Quercus ilex</style></keyword><keyword><style  face="normal" font="default" size="100%">reactive oxygen species</style></keyword><keyword><style  face="normal" font="default" size="100%">Resprouts</style></keyword><keyword><style  face="normal" font="default" size="100%">total antioxidant activity</style></keyword></keywords><dates><year><style  face="normal" font="default" size="100%">2003</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2003///</style></date></pub-dates></dates><urls><web-urls><url><style face="normal" font="default" size="100%">http://linkinghub.elsevier.com/retrieve/pii/S0981942802000074</style></url></web-urls></urls><volume><style face="normal" font="default" size="100%">41</style></volume><pages><style face="normal" font="default" size="100%">41 - 47</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">After ﬁre, holm oak (Quercus ilex L.) resprouts have a higher light availability and photosynthetic activity than control plants in intact vegetation. To assess the differences in protection between these plants, we determined, in two forests, changes in gas-exchange rates, chlorophyll ﬂuorescence parameters, chloroplast pigment content and total antioxidant activity (TAA) in different seasons, at different times of the day and in relation to leaf age. The end-point method used for TAA determination allowed the evaluation of the relative contribution of hydrophilic and lipophilic antioxidants in leaf extracts. High correlations were obtained between lipophilic TAA and certain chloroplast pigment content, the highest contribution being provided by b-carotene and the components of the xanthophyll cycle (zeaxanthin + antheraxanthin, violaxanthin). All leaves showed a much higher contribution (94–99%) of hydrophilic than lipophilic antioxidants to TAA. In summer, at midday, photosynthetic rates and TAA were higher in resprouts. In these plants, reduced xanthophyll-cycle participation (as shown by non-photochemical quenching (NPQ) and xanthophyll pool content) was compensated by an increased participation of hydrophilic antioxidants. No effect of time of day or plant age was observed. The results suggest that energy dissipation as heat, and detoxiﬁcation mechanisms contribute to the protective strategies of control plants and resprouts, albeit to a different extent.</style></abstract><issue><style face="normal" font="default" size="100%">1</style></issue></record><record><source-app name="Biblio" version="7.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">SPYROPOULOS, C G</style></author><author><style face="normal" font="default" size="100%">LAMBIRIS, M P</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Influence of Temperature on the Effects of Water Stress on Quercus Species</style></title><secondary-title><style face="normal" font="default" size="100%">Annals of Botany</style></secondary-title></titles><keywords><keyword><style  face="normal" font="default" size="100%">anthocyanin</style></keyword><keyword><style  face="normal" font="default" size="100%">carotenoids</style></keyword><keyword><style  face="normal" font="default" size="100%">chlorophyll</style></keyword><keyword><style  face="normal" font="default" size="100%">oak</style></keyword><keyword><style  face="normal" font="default" size="100%">Quercus coccifera</style></keyword><keyword><style  face="normal" font="default" size="100%">Quercus ilex</style></keyword><keyword><style  face="normal" font="default" size="100%">Temperature</style></keyword><keyword><style  face="normal" font="default" size="100%">water stress</style></keyword></keywords><dates><year><style  face="normal" font="default" size="100%">1979</style></year></dates><volume><style face="normal" font="default" size="100%">44</style></volume><pages><style face="normal" font="default" size="100%">215-220</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">Quercus coccifera L. and Q. ilex L. leaves, collected in winter, when the plants were in full turgor, were treated with polyethylene glycol (PEG) with a water potential of −48 and −65 bar, at 15 °C and at 30 °C, for 2 days. The response of each species differs with temperature as far as the plastid pigment, anthocyanin and soluble sugar content is concerned. Thus Q. ilex is affected more at 15 °C rather than at 30 °C, while in Q. coccifera, apart from a small increase in anthocyanins, no significant change was observed at 15 °C. On the contrary, at 30 °C significant changes were observed in all studied parameters. Chloroplast pigments decreased generally on the first day and their content either dropped further or increased to reach the control values on the second day. All treatments resulted in an increase in anthocyanin content. Soluble sugar content raised in Q. ilex at 15 °C and decreased in both species at 30 °C.</style></abstract></record></records></xml>