ISSN print edition: 0366-6352 ISSN electronic edition: 1336-9075 Registr. No.: MK SR 9/7 Published monthly

Antioxidant potential of crude and purified fractions from Bostrychia scorpioides (Hudson) Montagne (Rhodomelaceae)

Kaoutar Bougadra, Amine Elbouzidi, João Cotas, Ahmed Errami, Zahira Belattmania, Brahim Sabour, and Fouzia Hmimid

Laboratory of Plant Biotechnology, Ecology and Ecosystem Valorisation, URL—CNRST n◦10, Faculty of Sciences, Chouaib Doukkali University, El Jadida, Morocco

E-mail: bougadra.kaoutar@ucd.ac.ma

Received: 6 March 2026  Accepted: 9 June 2026

Abstract:

Natural antioxidants obtained from marine resources such as macroalgae should be studied in order to develop safer and more sustainable alternatives to synthetic compounds used in the food and pharmaceutical industry. Furthermore, multi-assay assessments contribute to a more thorough knowledge of antioxidant mechanisms, allowing researchers to identify bioactive fractions with focused potential for nutraceutical and medicinal applications. Bostrychia scorpioides (Hundson) Montagne 1842 is a red macroalga collected from the Oualidia lagoon (Moroccan atlantic coast). Its crude ethanolic extract, semi-purified and purified fractions of phycobiliproteins and sulfated galactans were evaluated for antioxidant activity using four complementary in vitro assays: nitric oxide (NO⁻) scavenging, hydrogen peroxide (H₂O₂) scavenging, lipid peroxidation inhibition, and β-carotene bleaching inhibition. The phycobiliproteins crude extract exhibited broad-spectrum antioxidant activity (93.92% ± 0.06), comparable to Trolox in the lipid peroxidation assay (83.47% ± 0.05). Notably, the second purified phycobiliprotein fraction showed exceptionnel NO scavenging activity (86.01% ± 0.12), surpassing the positive control Trolox (69.31% ± 0.01). In contrast, H₂O₂ scavenging was generally weaker in all the different samples. Overall, crude and semi-purified extracts had a stable, more broad-spectrum antioxidant effect likely due to synergistic interactions, unlike purified fractions with decreased or selective activity. These results highlight the importance of multi-assay profiling and the potential of B. scorpioides fractions for targeted nutraceutical and biomedical applications.

Graphical abstract

Graphical abstract illustrates the comprehensive experimental workflow applied to Bostrychia scorpioides, including the extraction, purification, and characterization of its bioactive compounds, as well as an evaluation of their antioxidant mechanisms

Keywords: Oxidative stress; Antioxidant activity; Nitric oxide radical inhibition; Hydrogen peroxide radical scavenging; β-carotene; Lipid peroxidation; Bostrychia scorpioides

Full paper is available at www.springerlink.com.

DOI: 10.1007/s11696-026-05195-5

Chemical Papers 80 (11) 13517–13530 (2026)