Banca de DEFESA: ALESSANDRA APARECIDA DE MELO SOUZA

Uma banca de DEFESA de MESTRADO foi cadastrada pelo programa.
STUDENT : ALESSANDRA APARECIDA DE MELO SOUZA
DATE: 21/10/2021
TIME: 13:30
LOCAL: Plataforma Google Meet
TITLE:

Callus induction, cell suspension production and phenolic compounds evaluation in Tecoma stans (Bignoniaceae).

KEY WORDS:

garden ipe, callogenesis, cells in suspension, phenolic compounds.

PAGES: 70
BIG AREA: Ciências da Saúde
AREA: Farmácia
SUMMARY:

The culture of calluses and cell suspensions is an important biotechnological tool that can be used to obtain bioactive vegetable substances, by adding growth regulators to the culture medium. Tecoma stans or ‘‘garden ipe’’ is a grove native to tropical regions of North America, used in Brazil for ornamentation of urban centers. This plant has actions against oxidative stress, angiogenesis, lipid peroxidation and inflammation processes, effects associated with phenolic compounds, especially flavonoids present in flowers and leaves. In order to establish callus cultures and cell suspensions from Tecoma stans leaf segments and evaluate the production of phenolic compounds, leaf explants were inoculated in MS medium, supplemented with 30 g L-1 of sucrose and added with 2, 4-D (0; 4.52; 9.05; 18.10 μM) and BAP (0; 4.44; 8.88; 17.75 μM) and their different combinations and incubated in the presence and absence of light. After 45 days of inoculation, the callus induction and oxidation percentage, the color, consistency, dry and fresh matter of the calluses and the contents of total phenols and flavonoids were evaluated, using usual methodologies. The callus growth curve was established by inoculating new leaf explants in MS medium supplemented with 30 g L-1 of sucrose and added with 9.05 µM 2,4-D + 17.75 µM BAP, for a period 120 days. Cell suspensions were obtained from the inoculation of friable calluses in liquid WPM medium, containing 30 g L-1 of sucrose and 9.05 μM 2,4-D, under agitation at 80 rpm, in the absence of light. Cell growth was assessed by determining the sedimented cell volume (VCS). The results obtained showed that the calluses induced in medium supplemented with 9.05 µM 2,4-D + 17.75 µM BAP, in the absence of light, presented high induction rate (93%), low oxidation rate (20%), yellow color, friable consistency, considerable values of fresh and dry matter, high levels of phenols and the highest levels of total flavonoids (119.88 ± 9.34 µg EqAG mg-1 EB and 97.11 ± 12.81 µg EqR mg-1 EB), respectively. So far, the growth curve has shown a sigmoidal pattern, with five distinct phases: lag, exponential, linear and stationary and declining. The initial suspensions at 15 days of age showed higher VCS and, consequently, greater cell growth, when subcultured in WPM medium supplemented with half the concentration of 2,4-D, compared to those subcultured in WPM medium containing 9.05 µM 2,4-D. No significant cell growth was observed from initial suspensions at 21 and 28 days of age. These results showed the possibility of obtaining calluses and cell suspensions of T. stans and phenolic compounds in vitro from callus cultures.

BANKING MEMBERS:
Presidente - 395916 - ANA HORTENCIA FONSECA CASTRO
Interna - 1540495 - LUCIANA ALVES RODRIGUES DOS SANTOS LIMA
Externo à Instituição - GERALDO ALVES DA SILVA - UNIFAL-MG