Pressurized Fluid Extraction of Bioactive Compounds from Phormidium Species

• Published in: Journal of agricultural and food chemistry 2008-05, Vol.56 (10), p.3517-3523
• Main Authors: Rodríguez-Meizoso, I, Jaime, L, Santoyo, S, Cifuentes, A, García-Blairsy Reina, G, Señoráns, F. J, Ibáñez, E
• Format: Article
• Language: English
• Subjects: Anti-Infective Agents - analysis; Anti-Infective Agents - pharmacology; Antimicrobial activity; antimicrobial properties; antioxidant activity; Antioxidants - analysis; Aspergillus niger - drug effects; beta-carotene; Bioactive Constituents; bioactive properties; Biological and medical sciences; Candida albicans - drug effects; carotenoids; Carotenoids - analysis; Cyanobacteria - chemistry; cytotoxicity; Escherichia coli - drug effects; fatty acids; Food engineering; Food industries; Food microbiology; Fundamental and applied biological sciences. Psychology; General aspects; heat treatment; lutein; Maillard Reaction; Maillard reaction products; microalgae; neoxanthin; Phormidium; Phormidiumsp; plant extracts; Pressure; pressurized liquid extraction; Solutions; Solvents; Staphylococcus aureus - drug effects; temperature; Terpenes - pharmacology; terpenoids; thermal degradation; violaxanthin
• ISSN: 0021-8561; 1520-5118
• DOI: 10.1021/jf703719p

In the search for new functional ingredients with potential use in the food industry, extracts of unknown species of microalgae, such as Phormidium species have been studied. Three solvents of different polarities (i.e., hexane, ethanol, and water) have been used to obtain pressurized liquid extracts with different compositions. Moreover, extractions were performed at four different extraction temperatures (50, 100, 150, and 200 °C) with 20 min as extraction time. Antioxidant activity of the extracts has been measured by the TEAC assay. In general, hexane and ethanol extracts showed a higher antioxidant capacity that was mainly attributed to carotenoid compounds, as the TEAC value trend seems to be similar to the carotenoid content of the extracts. On the other hand, the high antioxidant activity of the 200 °C water extracts is likely related to the presence of Maillard reaction compounds produced by thermal degradation of the sample. β-Carotene, lutein, violaxanthin, and neoxanthin were identified in 150 °C ethanol extracts. Four different microbial species (Escherichia coli, Staphylococcus aureus, Candida albicans, and Aspergillus niger) were used to screen the potential antimicrobial activity of the Phormidium sp. extracts. The most sensitive microorganism was the yeast, C. albicans, whereas the fungus, A. niger, was the most resistant. In general, no drastic differences were found for solvents and temperatures tested, showing a very diverse nature of the compounds responsible for the antimicrobial activity of these microalgae. In ethanol extracts, antimicrobial activity could be mainly attributed to the presence of terpenes (i.e., β-ionone, neophytadiene) and fatty acids (i.e., palmitoleic and linoleic acids) in the samples. Toxicity studies carried out with the extracts evaluated in the present work showed a cellular toxicity lower than those of other cyanobacteria such as Spirulina plantensis.