Seasonal Evaluation of Phlorotannin-Enriched Extracts from Brown Macroalgae Fucus spiralis

Abstract

Fucus spiralis that was collected in the four seasons was submitted to an extraction with ethanol:water (crude extracts Et80), followed by a liquid–liquid fractionation with organic solvents (fraction He from n-hexane; aqueous fractions AQ1, AQ2, AQ3 and AQ4; ethyl acetate fraction EA), with the aim of obtaining phlorotannin-enriched extracts. All the extracts (Et80, He, AQ1, AQ2, AQ3, AQ4 and EA) that were obtained for the F. spiralis of the four seasons were evaluated for their antioxidant capacity and total phenolic compounds. The summer extracts presented the highest contents in polyphenols (TPC), as well as the highest ferric reducing antioxidant power (FRAP), when compared to the samples from the other seasons. The reductive percentage of the DPPH (2,2-diphenyl-1-picryl-hydrazyl-hydrate) compound was similar between the seasons. For all the seasons, the EA extract showed the highest polyphenol content (TPC), and the highest antioxidant capacity (highest ferric reducing power (FRAP) and lowest concentration needed to reduce 50% of the DPPH compound), which is in agreement with a phlorotannin-enriched fraction. This study revealed that the polyphenol content and antioxidant power of the F. spiralis extracts are influenced by the time of harvest, as well as by the solvents used for their extraction.

Characterization and Cytotoxic Activity of Microwave-Assisted Extracted Crude Fucoidans from Different Brown Seaweeds

“…However, little bit of information is available in previous literature regarding fucoidan isolated from other species as Fucus spiralis with respect to extraction, chemistry, and bioactivities, compared to F. vesiculosus and F. serratus [ 6 , 7 , 8 ]. Most of bioactivities of F. spiralis have been documented to its phlorotannins containing fractions, which possessed potential antioxidant and cytoprotective activities [ 9 , 10 ]. Additionally, Laminaria saccharina (syn.…”

Estudio de la variabilidad en el tiempo y espacio de la actividad antioxidante y composición bioquímica de Kappaphycus alvarezii en diferentes densidades de siembra

“…Se prepararon ABTS y DPPH para estimar las actividades antioxidantes en extractos etanólico al 50%. El uso de solventes orgánicos combinados con agua puede producir un medio moderadamente polar que aumentará la extracción de antioxidantes 42,43 . Los altos valores de actividad antioxidante en extractos acuosos con 50% de solvente se deben al alto contenido de moléculas fenólicas presentes en los tejidos vegetales, puesto que al adicionar agua al disolvente orgánico facilita la extracción de químicos que son solubles en agua y/o solvente orgánico.…”

Phlorotannin and its Derivatives, a Potential Antiviral Molecule from Brown Seaweeds, an Overview

“…Four different phlorotannin derivatives were identified [80]. The method of liquid-liquid fractionation of Fucus spiralis with the use of organic solvents yields phlorotannin-rich extracts [3]. These techniques also help for assisting the separation of complex phlorotannins, which are covalently bound to polysaccharides [90].…”