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Role of phenolic acid during dehydration and rehydration of Ramonda serbica
No full textRamonda serbica Panc. is a poikilohydric, so called "resurrection plant" because of its desiccation tolerance. It belongs to a small group of poikilohydric angiosperms of the northern hemisphere. This species is a perennial herbaceous shade-adapted plant, considered as homoiochlorophyllous poikilohydric plant, since it preserves more than 80% of the chlorophyll content during dehydration. Following drought there is an increase in the production of reactive oxygen species in the tissues. To defend against oxidants plants have low-molecular mass antioxidants and protective enzymes which catalyse the elimination of ROS in the cells. Phenolic acids are simple polyphenols. The polyphenolic structure allows the scavenging of radical species and functions as metal chelators. the antioxidative effect of flavonoids lies in their radical-scavenging properties towards all types of oxidising radicals. This action becomes particularly important during water depletion since superoxide radical increase. The aim of the present research is to evaluate in Ramonda serbica the role of phenolic acid in the tolerance to desiccation compared with that of the more studied antioxidants ascorbate and glutathione
Role of phenolics in the antioxidative status of the resurrection plant Ramonda serbica during dehydration and rehydration
No full textElementi minerali ed acidi organici nel succo cellulare di foglie di Ramonda serbica sottoposta a disidratazione e reidratazione
No full textSenescence- and drought-related changes in peroxidase and superoxide dismutase isoforms in leaves of Ramonda serbica
No full textPlasma membrane lipids in the resurrection plant Ramonda serbica following dehydration and rehydration
No full textPhotosystem II photochemical efficiency, zeaxanthin and antioxidant contents in the pokilohydric Ramonda serbica during dehydration and rehydration
No full textPotere antiossidativo in foglie di Ramonda serbica sottoposta a disidratazione
No full textRamonda serbica Panc. è una "pianta resurrection" per la sua proprietà di tollerare la disidratazione. Una comune caratteristica delle piante sottoposte a disidratazione è rappresentata dalla loro capacità di incrementare la produzione di specie attivate dell'ossigeno nei loro tessuti. Per difendersi, le piante hanno antiossidanti a basso peso molecolare come ascorbato e glutatione ed enzimi protettivi che catalizzano la eliminazione di forme attivate dell'ossigeno nelle cellule. Gli acidi fenolici sono semplici polifenoli. La struttura polifenolica ha la capacità di eliminare le specie radicaliche e funziona come chelante di metalli prevenendo reazioni tipo Fenton. Lo scopo della ricerca è quello di valutare in Ramonda serbica il ruolo di acidi fenolici nella tolleranza alla disidratazione rispetto a quello più conosciuto degli antiossidanti ascorbato e glutatione
Potere antiossidativo in foglie della pianta resurrection Ramonda serbica sottoposta a disidratazione
No full textRamonda serbica plants were dehydrated up to 11.2% relative water content and then rehydrated. Ascorbate and glutathione contents increased at the end of dehydration and approached to control values at the end of rehydration. During dehydration phenolic acids decreased and returned to control values at the end of rehydration. In Ramonda serbica leaves the most representative phenolic acids were protocatechuic, p-hydroxybenzoic and chlorogenic acids. Most concentrated phenolc acids such as protocatechuic and chlorogenic acids accumulated during the first period of rehydration when reduced form of ascorbate decreased
Going Beyond Counting First Authors in Author Co-citation Analysis
Full text linkThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
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