Banca de DEFESA: FERNANDA PRISCILA SANTOS REGINALDO

Uma banca de DEFESA de DOUTORADO foi cadastrada pelo programa.
STUDENT : FERNANDA PRISCILA SANTOS REGINALDO
DATE: 25/03/2021
TIME: 14:00
LOCAL: Videoconferência
TITLE:

Selaginella convoluta (Arn.) Spring: uma abordagem fitoquímica aliada a estudos ômicos

KEY WORDS:

Selaginellins; Anabasine; Proteoma; Metaboloma; Metiljasmonato;

PAGES: 314
BIG AREA: Ciências da Saúde
AREA: Farmácia
SUMMARY:

The genus Selaginella, the largest genus of Lycopodiophyta comprise about 700-
750 species, which several species are recognized for their pharmacological activities.
Our overview of the phytochemical and bioactive aspects pointed out that future studies
should afford valuable new data on better explore the biological potential of the flavonoid
amentoflavone and their derivatives as chemical bioactive entities; develop studies about
toxicity and, finally, concentrate efforts on elucidate mechanisms of action for biological
properties already reported. The family Selaginellaceae managed to survive the many
biotic and abiotic pressures during the last 400 million years. Several species of the genus
Selaginella have been acquired an interesting evolutionary trait: desiccation tolerance
(DT). Selaginella convoluta is a desiccation-tolerant plant native from Brazilian semiarid.
DT plants have highly effective drought-resistance mechanisms that allow their survival
under extreme conditions. In this study we investigate Selaginella convoluta in two
hydration states: (i) dehydrated – harvested in the natural semiarid environment; and (ii)
hydrated – after acclimatization in lab. The proteome dataset pointed out that shoots and
roots appear to have different strategies in response to different hydration states; however,
appear to have a well-orchestrated response to regulate desiccation tolerance. The
presence of enzymes involved in the biosynthesis of specialized metabolites such as
phenolic, terpenoid, as well as metabolites containing nitrogen/sulfur were identified
through proteomic analysis. The NMR-based metabolite profiling showed the presence
of metabolites such as carbohydrates and phenolic derivatives related to desiccation
tolerance events, corroborating with the proteome data. As an unprecedented finding, the
most important annotated alkaloid was anabasine. The specialized metabolites,
flavonoids, bioflavonoids and selaginellins were the main phenolic derivatives annotated.
Thus, we performed a LC-MS/MS analysis combined with the molecular networking
(MN) approach to assess the chemodiversity of flavonoids and selaginellins. So far, this
has been the first study on Selaginella spp. using the MN approach that showed not only
a proposal of the fragmentation pattern for all the selaginellins annotated, but also the
prediction of new selaginellins based on the MS/MS spectral data. Several biological
potentials of selaginellin from Selaginella spp. have been reported. Selaginellins are
naturally produced at low levels in the plant, which makes the chemical extraction of
these metabolites difficult and time consuming. In this context, methyl jasmonate (MeJA)
has been used to induce specialized metabolites of pharmaceutical interest. Our data
showed that MeJA can be an interesting alternative to induce the accumulation of
selaginellins in S. convoluta. In addition, the in silico studies pointed out interesting
bioactive potentials for selaginellins: antineurodegenerative, antiproliferative and
antiparasitic. The MN approach allowed the prediction of seven unprecedent
selaginellins, which contribute as a new chemical information for this species.

BANKING MEMBERS:
Externo à Instituição - EDUARDO LUIS KONRATH
Externo ao Programa - 1228866 - EDUARDO LUIZ VOIGT
Interna - 1201781 - FERNANDA NERVO RAFFIN
Externo à Instituição - FERNANDO BATISTA COSTA
Presidente - 1871916 - RAQUEL BRANDT GIORDANI