Optimization of the extraction process of phenolic compounds from the brown algae Sargassum fluitans Børgesen ( Børgesen )

Sargassum fluitans is a brown seaweed species that annually arrive to Cuban shores in extensive biomass amounts. It contains considerable content of total polyphenols as structural constituents of vegetal cell walls, which can be extracted from this species for therapeutic applications as antioxidants, antiviral and anti-inflammatory agents. In previous research, there were implemented the extraction method by maceration with heat under agitation, but yields of total polyphenols were found lower than required for an efficient extraction process. Therefore, this work was aimed to optimize the extraction conditions of total polyphenol-rich compounds. For this, a complete factorial design 32 with replicates in the center of the plane was studied, together with the resulting effect of extraction time and percentage of ethanol in the extraction solution as independent variables. The response variable used was total polyphenols’ content, as determined by the Folin-Ciocalteu method. Optimal conditions were successfully established, improving yields of total polyphenols. Increaing ethanol concentration was detrimental for yields, while enlarging the extraction time was not so relevant for the efficiency of the process. The resulting regression model coefficients provided optimal design conditions, which were experimentally corroborated: 17.75 % ethanol hydroalcoholic solution (10:1 mL/g of dry seaweed) and incubation at 50 oC under stirring at 800 rpm for 123.5 min. These conditions allowed obtaining up to 8.66 mg of total polyphenols per g of dry seaweed. These conditions are relevant to implement efficient processes for polyphenols extraction from these species, as raw material for the biopharmaceutical industry.