Antioxidant and Antimicrobial Activity of Plants from Portuguese Flora

• Autor(a) principal: Ribeiro, Alexandre
• Data de Publicação: 2021
• Tipo de documento: Dissertação
• Idioma: eng
• Título da fonte: Repositório Científico de Acesso Aberto de Portugal (Repositórios Cientìficos)
• Texto Completo: http://hdl.handle.net/10400.22/17539
• topic: Euphorbia; Trifolium; Antioxidants; Antibacterial; Phytochemicals

Through the years, we have seen the important role of plants in heallth, with valuable drugs being approved derived from phytochemicals. The diversity found in the plant kingdom makes that the properties of many medicinal plants remain unknown. Therefore, this research aims to evaluate the biological activity through antioxidante and antibacterial in vitro assays of three plants from Portuguese flora. It was prepared aqueous and methanolic extracts (AE amd ME, respectively) from Euphorbia paralias, Euphorbia hirsuta, and Trifolium tomentosum. Their total phenolic contente (TPC), capacity to scavenge DPPH radical, and ability to chelate iron ions were evaluated as well as their antibacterial activity agianst Escherichia coli and Staphylococcus aureus, through disc diffusion and broth microdilution methods. Euphorbia species presented their higher radical scavenging capacity (IC50˂50 µg/mL). The ME of E. paralias presented the highest TPC (293.37 ± 20.25 mg GAE/g) and also had the best performance in chelating iron ions. This same extract, along with ME of E. hirsuta, promoted moderate growth inhibition of S. aureus at 10 mg/ml with a MIC value of 1.0 and 2.0 mg/ml, respectively. Our findings provided preliminar knowledge about these plants and highlighted the potentialities of the Euphorbia genus.