Banca de QUALIFICAÇÃO: VERONICA GIULIANI DE QUEIROZ AQUINO MARTINS

Uma banca de QUALIFICAÇÃO de DOUTORADO foi cadastrada pelo programa.
STUDENT : VERONICA GIULIANI DE QUEIROZ AQUINO MARTINS
DATE: 16/05/2025
TIME: 13:30
LOCAL: videoconferencia - https://meet.google.com/jkv-btrv-jtk
TITLE:

Investigation of the Antioxidant and Anti-inflammatory Potential of Myrciaria tenella (DC.) O. Berg (Lamiaceae) and Coccoloba alnifolia Casar (Polygonaceae) Extracts: Correlations Between Biological Activities and Phytochemical Composition

KEY WORDS:

cauaçu, cambuí, antioxidant, phytocompounds, anti-inflammatory potential, phenolics, nutraceuticals, Tenebrio molitor, zebrafish, 3T3, RAW 264.7

PAGES: 176
BIG AREA: Ciências Biológicas
AREA: Bioquímica
SUBÁREA: Biologia Molecular
SUMMARY:

Medicinal plants have significant therapeutic potential due to the presence of biomolecules with antioxidant and anti-inflammatory properties. These molecules help combat oxidative stress and contribute to the prevention and treatment of various diseases. In this study, it was evaluated the fruits of Myrciaria tenella (Cambuí) and Coccoloba alnifolia (Cauaçu), species commonly used in food and traditional medicine, particularly as herbal teas. Members of the Myrciaria genus are known for their extracts rich in phenolic compounds and terpenoids, exhibiting antioxidant, anti-inflammatory, antihypertensive, antimicrobial, and gastroprotective activities. Extracts from the Coccoloba genus have demonstrated larvicidal activity against Aedes aegypti, as well as antioxidant, antifungal, and antidiabetic effects.The aim of this study was to obtain and characterize extracts from unripe and ripe fruits of M. tenella and C. alnifolia, and to evaluate their antioxidant and anti-inflammatory activities through both in vitro and in vivo assays, along with assessments of toxicity. Aqueous and 70% hydroethanolic extracts were prepared, resulting in four extract types per species: unripe aqueous (VA), unripe hydroethanolic (VE), ripe aqueous (MA), and ripe hydroethanolic (ME). Phytochemical characterization included quantification of total phenolics, anthocyanins, and flavonoids, as well as high-performance liquid chromatography with diode-array detection (HPLC-DAD). Antioxidant activity was done using biochemical assays as total antioxidant capacity (TAC), DPPH radical scavenging, reducing power, and copper and iron chelation. Cytotoxicity was evaluated using the MTT assay in NIH/3T3 fibroblast cells. In the absence of cytotoxicity, further assays examined cell migration and protection against oxidative stress. In RAW 264.7 macrophages, nitric oxide production and protection against oxidative agents were done. In vivo assays using Tenebrio molitor larvae evaluated both toxicity and protection against CuSO₄-induced stress, as well as effects on melanization. Zebrafish larvae were used as a second in vivo model to assess toxicity and antioxidant protection in the presence of H₂O₂, with reactive oxygen species (ROS) levels measured via fluorescence. Extracts from both species exhibited strong free radical scavenging and metal-chelating activities. They were non-cytotoxic to NIH/3T3 cells and protected them from CuSO₄/ascorbate-induced oxidative damage by reducing intracellular ROS levels. In RAW 264.7 macrophages, all extracts mitigated H₂O₂-induced oxidative stress, with C. alnifolia MA extract significantly reducing nitric oxide production following LPS stimulation. In T. molitor larvae, M. tenella extracts, in special VE, showed low toxicity and protective effects against CuSO₄, with VE and MA having a high activity reducing melanization. Among C. alnifolia extracts, MA and VA exhibited the strongest protective effects and melanization reduction. HPLC-DAD analysis identified gallic acid, catechin, and kaempferol in both species; C. alnifolia additionally contained epicatechin, p-coumaric acid, rutin, quercitrin, myricetin, and neohesperidin. All C. alnifolia extracts, in special for VE and MA, which significantly reduced ROS levels in H₂O₂-exposed zebrafish larvae. In conclusion, Myrciaria tenella and Coccoloba alnifolia are rich in phytoconstituents with potent antioxidant and anti-inflammatory activities, demonstrating promising potential for therapeutic applications and warranting further investigation for safe and effective use.

COMMITTEE MEMBERS:
Presidente - 2962496 - RAFAEL BARROS GOMES DA CAMARA
Externo ao Programa - ***.808.346-** - LETÍCIA BARBOSA SANTOS - UFMG
Externa ao Programa - ***.574.694-** - NATHALIA MAÍRA CABRAL DE MEDEIROS - UFRN