Banca de DEFESA: MAYLLA MARIA CORREIA LEITE SILVA

Uma banca de DEFESA de DOUTORADO foi cadastrada pelo programa.
STUDENT : MAYLLA MARIA CORREIA LEITE SILVA
DATE: 10/04/2026
TIME: 08:30
LOCAL: Videoconferência
TITLE:

BLENDS OF SULFATED POLYSACCHARIDES FROM RED ALGAE AND AQUEOUS EXTRACTS OF LEMON AND GARLIC: PRODUCTION, CHARACTERIZATION, AND EVALUATION OF IN VITRO AND IN VIVO ANTIOXIDANT ACTIVITY

KEY WORDS:

Oxidative stress; Sulfated polysaccharides; Antioxidant blends; Biocompatibility.

PAGES: 156
BIG AREA: Ciências Biológicas
AREA: Bioquímica
SUMMARY:

Controlling oxidative stress is essential for the prevention and treatment of several chronic diseases, making the search for safe and effective antioxidants a priority. Garlic (Allium sativum) and lemon (Citrus limon) are recognized sources of bioactive compounds; however, their use at high doses may lead to adverse effects or limitations related to bioavailability. In this context, marine polysaccharides, such as sulfated agarans from Gracilaria birdiae, emerge as promising alternatives to compose matrices capable of stabilizing and enhancing these properties. In this study, blended formulations combining garlic–lemon extract (LG) with sulfated agaran (SPGB) were developed. Initially, antioxidant potential and redox behavior were evaluated through in vitro assays, along with stability and biological safety in cellular models and Danio rerio embryos. The LG:SPGB (3:1) blend stood out, showing higher reducing capacity and improved metal-chelating performance compared to the isolated extract, in addition to enhanced stability and reduced cytotoxicity. The presence of agaran allowed the maintenance of antioxidant efficiency even with reduced LG concentration, contributing to minimize potential adverse effects associated with compounds such as allicin and diallyl disulfide, as well as flavonoids like hesperidin and quercetin. Additionally, the biological effects of the formulations were investigated in cellular models and zebrafish under H₂O₂-induced oxidative stress. The B3:1 blend showed superior performance by promoting reduction of reactive oxygen species, preservation of cytoskeletal organization, maintenance of cell density, and increased glutathione S-transferase (GST) activity, indicating a consistent cytoprotective effect. These findings suggest a functional complementarity between the plant extract and the agaran, contributing to improved redox stability and cellular protection. Overall, the data demonstrate that these blends represent biocompatible and promising systems with potential applications in nutraceutical and pharmaceutical products, although further studies are required for validation in more complex models and for bioavailability assessment.

COMMITTEE MEMBERS:
Externo à Instituição - DIEGO DE ARAUJO SABRY - IFPI
Presidente - 2195251 - HUGO ALEXANDRE DE OLIVEIRA ROCHA
Externo ao Programa - 3060683 - LEONARDO THIAGO DUARTE BARRETO NOBRE - nullExterno à Instituição - MOACIR FERNANDES DE QUEIROZ NETO - UFPB
Externo à Instituição - WESLLEY DE SOUZA PAIVA - UPE