| Autor: |
Fernandes-Negreiros MM; Department of Biochemistry, Universidade Federal do Rio Grande do Norte, Natal, Rio Grande do Norte 59.078-970, Brazil., Batista LANC; Department of Biochemistry, Universidade Federal do Rio Grande do Norte, Natal, Rio Grande do Norte 59.078-970, Brazil., Silva Viana RL; Department of Biochemistry, Universidade Federal do Rio Grande do Norte, Natal, Rio Grande do Norte 59.078-970, Brazil., Araujo Sabry D; Department of Biochemistry, Universidade Federal do Rio Grande do Norte, Natal, Rio Grande do Norte 59.078-970, Brazil., Paiva AAO; Department of Biomedicine, Faculdade Nova Esperança (FACENE), Mossoró 59.628-000, Brazil., Paiva WS; Department of Biochemistry, Universidade Federal do Rio Grande do Norte, Natal, Rio Grande do Norte 59.078-970, Brazil., Machado RIA; Department of Biochemistry, Universidade Federal do Rio Grande do Norte, Natal, Rio Grande do Norte 59.078-970, Brazil., Sousa Junior FL; Laboratório de Química de Coordenação e Polímeros-LQCPol, Instituto de Química, Universidade Federal do Rio Grande do Norte-UFRN, Natal-RN 59.078-970, Brazil., de Lima Pontes D; Laboratório de Química de Coordenação e Polímeros-LQCPol, Instituto de Química, Universidade Federal do Rio Grande do Norte-UFRN, Natal-RN 59.078-970, Brazil., Vitoriano JO; Centro Integrado de Inovação Tecnológica do Semiárido (CiTED), Universidade Federal Rural do Semi-Árido, Mossoró 59.625-900, Brazil., Alves Junior C; Centro Integrado de Inovação Tecnológica do Semiárido (CiTED), Universidade Federal Rural do Semi-Árido, Mossoró 59.625-900, Brazil., Lanzi Sassaki G; Departament of Biochemistry, Federal University of Parana, Curitiba 81.531-980, Brazil., Rocha HAO; Department of Biochemistry, Universidade Federal do Rio Grande do Norte, Natal, Rio Grande do Norte 59.078-970, Brazil. |
| Abstrakt: |
A 12.4 kDa laminarin (LM) composed of β(1→3)-glucan with β(1→6)-branches was extracted from brown seaweed Lobophora variegata and modified via carboxylation using dielectric barrier discharge (LMC), conjugation with gallic acid (LMG), and sulfation (LMS). Analyses of the chemical composition of LMC, LMG, and LMS yielded 11.7% carboxyl groups, 1.5% gallic acid, and 1.4% sulfate content, respectively. Antioxidant activities of native and modified laminarins were assessed using six different in vitro methods. Sulfation stopped the antioxidant activities of LM. On the other hand, carboxylation improved cooper chelation (1.2 times). LMG was found to be a more efficient antioxidant agent than LM in terms of copper chelation (1.3 times), reducing power (1.3 times), and total antioxidant capacity (80 times). Gallic acid conjugation was further confirmed using Fourier transform infrared spectroscopy (FT-IR) and one- and two-dimensional NMR spectroscopy analyses. LMG also did not induce cell death or affect the cell cycle of Madin-Darby canine kidney (MDCK) cells. On the contrary, LMG protected MDCK cells from H 2 O 2 -induced oxidative damage. Taken together, these results show that LMG has the potent antioxidant capacity, and, therefore, potential applications in pharmacological and functional food products. |
