Banca de QUALIFICAÇÃO: SIMONE ALVES SERAFIM ROCHA

Uma banca de QUALIFICAÇÃO de DOUTORADO foi cadastrada pelo programa.
STUDENT : SIMONE ALVES SERAFIM ROCHA
DATE: 09/09/2022
TIME: 14:00
LOCAL: videoconferência
TITLE:

CHEMICAL CONSTITUENTS AND BIOLOGICAL ACTIVITIES OF SPECIES BELONGING TO CAATINGA: Varronia dardani Taroda J.Mill. (Boraginaceae) and Marsdenia Megalantha Goyder & Morillo (Apocynaceae).

KEY WORDS:

Marsdenia megalantha, Polyoxypregnane, Apocinaceae, Varronia dardani, coridaquinone.

PAGES: 165
BIG AREA: Ciências Exatas e da Terra
AREA: Química
SUBÁREA: Química Orgânica
SPECIALTY: Química dos Produtos Naturais
SUMMARY:

Considered exclusively Brazilian, the caatinga is the most studied biome from a chemical and biological point of view, thus contributing to the discovery of new drugs in the search for cures for diseases. This work describes the chemical and biological investigation of two species of plants endemic to the semiarid region of northern Rio Grande do Sul: the species Marsdenia megalantha Goyder e Morilo (Apocynaceae) and Varronia dardani Torada J.Mill. (Boraginaceae). The study carried out on the roots allowed the isolation of four substances. From the 70% hydroalcoholic extract, it was possible to isolate six substances with pegnane type skeletons. Four of them are glycosylated. All chemical constituents isolated were used spectroscopic techniques such as hydrogen nuclear magnetic resonance (1H NMR) and carbon-13 (13C NMR), including two-dimensional techniques (COSY, HMQC, HMBC and NOESY) and compared with data available in the literature. The chemical study of the roots of V. dardani resulted in the isolation and structural identification of two naphthoquinones: cordiaquinones A and B, which despite being substances already known in the scientific literature, are cited for the first time in the species. These substances showed good results in in vitro activity against two tumor cell lines: HCT-116 (Colorectal Adenocarcinoma) and MDA-MB-231 (Breast Adenocarcinoma) demonstrating a strong potential for cytotoxic activity against the evaluated human tumor cell lines, proving the biological potential of species from the caatinga and encouraging the continuity of this study with the prospect of discovering mechanisms of action of anticancer molecules. The essential oil of the leaves was obtained by hydrodistillation, analyzed and identified by GC-MS and GC-FID, resulting in the identification of 54 chemical constituents, corresponding to a total of 99% of the chemical composition of the oil, consisting basically of monoterpenes and sesquiterpenes. The biological potential of the essential oil showed antimicrobial activity against Staphylococcus aureus, Escherichia coli and Pseudomonas aeruginosa and antifungal activity against Candida albicans and Candida parapsilosis.

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Externa ao Programa - ***.944.634-** - MANOELA TORRES DO RÊGO - UFRN
Externa à Instituição - MARIANA LAUNDRY DE MESQUITA - UnB
Presidente - 1569526 - RENATA MENDONÇA ARAUJO