In this study, Pelvetia canaliculata L. macroalga, collected from the Atlantic Portuguese coast, was used as a source of bioactive compounds, mostly antioxidants, to incorporate them in sunflower oil with the aim of increasing its biological value and oxidative stability. The lyophilized alga was added to the oil, and ultrasound-assisted extraction (UAE) was performed. Algae concentration and UAE time varied following a central composite rotatable design (CCRD) to optimize extraction conditions. The following parameters were analyzed in the oils: oxidation products, acidity, color, chlorophyll pigments, carotenoids, flavonoids, total phenolic content, antioxidant activity by DPPH (2,2-diphenyl-1-picrylhydrazyl) and FRAP (ferric reducing antioxidant power) assays, and sensory analysis. Extraction conditions did not affect the acidity and the amount of oxidation products in the oil. Chlorophylls and carotenoid contents increased with algae concentration, while flavonoid extraction did not depend on algae content or UAE time. Total phenolics in the oil were highly related only to FRAP antioxidant activity. Storage experiments of supplemented oil (12.5% algae; 20 min UAE) were carried out under accelerated oxidation conditions at 60 °C/12 days. Antioxidant activity (FRAP) of supplemented oil was 6-fold higher than the value of non-supplemented oil. Final samples retained 40% of their initial antioxidant activity. The presence of algae extracts contributed to the increased oxidative stability of sunflower oil.

Crithmum maritimum L., or sea fennel, is an edible halophyte plant, rich in phenolic compounds with antioxidant and antimicrobial activities, that naturally grows in Mediterranean coasts. This study aims to incorporate bioactive compounds extracted from lyophilized Crithmum maritimum to sunflower oil assisted by ultrasounds (UAE), to improve its biological value and oxidative stability. UAE conditions were optimized as a function of time (5–20 min) and lyophilized plant concentration (5–20% m/v). The experiments were dictated by a central composite rotatable matrix. Oxidation products were not influenced by UAE conditions. Acidity, chlorophyll, and carotenoid contents were affected by both factors, while total phenols, flavonoids, and antioxidant activity (FRAP method) only increased with plant concentration. Response surfaces were fitted to these experimental results. Flavonoids were highly related with oil antioxidant activity. No sensory defects were detected in supplemented oil (12.5% m/v plant/5 min UAE). The oxidative stability of this oil was evaluated at 60 °C/12 days. Chlorophylls, phenols, radical scavenging (DPPH), and antioxidant activities decreased over time but were always higher than the values in non-supplemented oil (8.6 and 7-fold with FRAP and DPPH, respectively). C. maritimum presented high amounts of bioactive compounds with antioxidant activity, adequate for sunflower oil supplementation by UAE.

Antioxidantes naturais são substâncias capazes de reduzir os impactos dos radicais livres no organismo. Dentre as principais fontes de antioxidantes estão alimentos, vitaminas, chás e compostos inorgânicos como o zinco. Diversos fatores influenciam no potencial antioxidantes dessas fontes, sendo, portanto, de suma importância a escolha de produtos que venham contribuir com a redução mais eficiente destes radicais. Por outro lado, devese buscar produtos seguros que não venham oferecer riscos ao consumi-los. Substâncias toxicas devem estar ausentes ou dentro dos limites permissíveis. Assim, as aflatoxinas, potentes agentes carcinogênicas produzidas por fungos, especialmente dos gêneros Aspergillus, Fusarium e Penicillum, desenvolve-se em várias matrizes, incluindo também as plantas medicinais. Nas quais devem estar ausentes, segundo legislações vigentes. Nesse contexto, o estudo teve como objetivo avaliar o potencial antioxidante das ervas mais consumidas no município de Salvador bem como contribuir para a avaliação de risco desses produtos quanto à contaminação por aflatoxina. A avaliação da atividade antioxidante foi feita através do método de DPPH e a detecção de aflatoxinas utilizou-se a cromatografia em camada delgada analítica. As amostras de erva doce apresentaram os maiores teores de compostos fenólicos e atividade antioxidante. Entretanto, cerca de 52% das amostras apresentaram fluorescência características de aflatoxinas. Demonstrando assim, a importância da constante avaliação de risco e adoção de boas práticas de armazenamento durante a comercialização desses produtos.Palavras-chave: micotoxinas, avaliação de risco, atividade antioxidante, compostos fenólicos totais.