Title : Antioxidative and produtive potencial of restinga shrub species
Abstract:
The restinga is an ecosystem strongly impacted by anthropic action, such as the Fundão Dam Failure, in 2015. Analyzes under controlled conditions constitute an important tool for defining strategies for repairing the potentially damage of passage of mine tailings from the Fundao Dam through the coastal region, and may also identify patterns of plant development and species with unexplored productive and phytochemical potential for the proposition of mitigation measures. As such, the present work aimed to characterize the photosynthetic and oxidative system among five shrub species from restinga under greenhouse conditions: Chrysobalanus icaco L. (CHRY), Eugenia astringens Cambess. (EUG), Guapira pernambucensis (Casar.) Lundell. (GUA), Myrciaria strigipes O Berg (MYRC) and Psidium cattleyanum Sabine (PSID). For this, we evaluated the changes in the different phases of fluorescence of chlorophyll a emission kinetics of transient OJIP, as well as functional and structural parameters of the JIP test. In the same leaves, the capacity of the antioxidant system was also evaluated. CHRY and GUA plants showed evidence of a decreased photochemical activity, such as a reduced connectivity between adjacent Photosystems II (PSII) at the level of the antenna complexes and a smaller pool of plastoquinone and/or photosystem I (PSI) electron end acceptors per center of active reaction of the PSII, as well as greater sensitivity to the level of Oxygen Evolution Complex on the PSII donor side. In these species, parameters of structure and function of the photosynthetic apparatus indicate that although CHRY and GUA tend to absorb and capture more energy per reaction center in the PSII, part of this energy is released in dissipative processes that may result in less energy flow for electron transport beyond QA and intersystem of the electron transport chain, resulting in the reduction of photosynthetic performance in both species. Among the analyzed species, the representatives of Myrtaceae Family showed higher bioactive functional properties and antioxidant activity, suggesting a great capacity for adjustment of the antioxidant system and biological activity. Thus, the results so far reveal the susceptibility of the photosynthetic and antioxidant system of C. icaco and G. pernambucensis and highlight the myrtaceae species as having the greatest potential for primary and antioxidant productivity, indicating viability of the restinga species evaluated as prospective sources of phytopharmaceuticals.
What will audience learn from your presentation?
- The study of different species of the restinga ecosystem aims to identify important plant development patterns to propose mitigation measures in impacted environments.
- Chlorophyll a fluorescence analysis is an excellent indicator of ecosystem primary production and species screening.
- Restinga species are a potential source of natural antioxidants and knowledge of these species provides new ecosystem services to this susceptible Brazilian mosaic of plant communities.
