Antioxidant activity of the microalga Spirulina maxima
M.S. Miranda1, R.G. Cintra2, S.B.M. Barros2 and J. Mancini-Filho2
1Faculdade de Farmácia e Bioquímica, Universidade Federal da Bahia, Salvador, BA, Brasil 2Faculdadede Ciências Farmacêuticas, Universidade de São Paulo, São Paulo, SP, Brasil
J. Mancini-Filho FCF, USP Av. Prof. Lineu Prestes, 580 Bloco 14 05508-900 São Paulo, SP Brasil Fax: 55 (011) 815-4410 E-mail: email@example.com Research supported by CAPES and CNPq (No. 520456/95). Publication supported by FAPESP.
Received September 26, 1997 Accepted May 27, 1998
Spirulinamaxima, which is used as a food additive, is a microalga rich in protein and other essential nutrients. Spirulina contains phenolic acids, tocopherols and ß-carotene which are known to exhibit antioxidant properties. The aim of the present study was to evaluate the antioxidant capacity of a Spirulina extract. The antioxidant activity of a methanolic extract of Spirulina was determined in vitro andin vivo. The in vitro antioxidant capacity was tested on a brain homogenate incubated with and without the extract at 37oC. The IC50 (concentration which causes a 50% reduction of oxidation) of the extract in this system was 0.18 mg/ml. The in vivo antioxidant capacity was evaluated in plasma and liver of animals receiving a daily dose of 5 mg for 2 and 7 weeks. Plasma antioxidant capacity wasmeasured in brain homogenate incubated for 1 h at 37oC. The production of oxidized compounds in liver after 2 h of incubation at 37oC was measured in terms of thiobarbituric acid reactant substances (TBARS) in control and experimental groups. Upon treatment, the antioxidant capacity of plasma was 71% for the experimental group and 54% for the control group. Data from liver spontaneous peroxidationstudies were not significantly different between groups. The amounts of phenolic acids, α-tocopherol and ß-carotene were determined in Spirulina extracts. The results obtained indicate that Spirulina provides some antioxidant protection for both in vitro and in vivo systems.
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Microalgae Antioxidant activity Spirulina maxima Phenolic compounds ß-Carotene α-TocopherolPhytoplankton comprises organisms such as diatoms, dinoflagellates, green and yellow-brown flagellates, and blue-green algae. As photosynthetic organisms, these groups play a key role in the productivity of oceans and constitute the basis of the marine food chain. Among several alga genera, Spirulina and Chlorella deserve special attention due to their importance as human food and their in vitroand/or in vivo antioxidant potential (1). Spirulina algae are an important source
of nutrients in the traditional diet of some populations of Africa and Mexico. These algae can be extensively grown to obtain a protein-rich material of alimentary use (foodstuff for diet complementation) or industrial use (blue pigments, emulsifiers, thickening and gelling agent). The chemical composition ofSpirulina indicates that it has a high nutritional value due to a wide range of essential nutrients, such as vitamins, minerals and proteins (1). Moreover, it contains
Braz J Med Biol Res 31(8) 1998
M.S. Miranda et al.
other components such as ω-3 and ω-6 polyunsaturated fatty acid, provitamins and phenolic compounds. In addition, these algae can be produced in large-scale systems (2).There is a current worldwide interest in finding new and safe antioxidants from natural sources such as plant material to prevent oxidative deterioration of food and to minimize oxidative damage to living cells (3). Experimental and epidemiological evidence suggests the participation of free radicals in tissue damage and pathological processes such as cardiovascular disease and cancer (4,5). The...