Pressurized liquids as an alternative green process to extract antiviral agents from the edible seaweed Himanthalia elongata

Abstract

Pressurized liquid extraction (PLE), an environmentally friendly technique, was used to obtain antiviral compounds from the edible seaweed Himanthalia elongata. The antiviral properties of PLE extracts (hexane, ethanol, and water) were evaluated against herpes simplex virus type 1 (HSV-1) at different stages during viral infection. Pre-treatment of Vero cells with 75 μg mL −1 of ethanol extract inhibited virus infection by approximately 90%, whereas the same concentration of water and hexane extracts reduced the virus infectivity to 78% and 70%, respectively. Moreover, ethanol extract was also more effective against HSV-1 intracellular replication than water and hexane extracts. The antiviral activity of water PLE extract was found to correlate with polysaccharides, since the polysaccharide-rich fraction isolated from this extract showed higher antiviral activity than the original water extract. A GC-MS characterization of the hexane and ethanol extracts showed that the antiviral activity of the hexane extract seemed to be related with the presence of fucosterol; meanwhile, in the case of the ethanol extract, other compounds, besides fucosterol, could be involved in this activity. Results demonstrated that PLE was an appropriate technique to obtain antiviral agents from H. elongata. These antiviral compounds were in addition to polysaccharides, which are the antiviral agents usually proposed when studying seaweeds.

Advanced Technologies for the Extraction of Marine Brown Algal Polysaccharides

“…Depending on the solvent used for the extraction and its diverse working conditions, PLE is often called pressurized fluid extraction (PFE), pressurized solvent extraction (PSE), accelerated solvent extraction (ASE), subcritical water extraction (SWE) or hot water extraction (HWE) [80]. For polysaccharide extraction from brown algae different type of static [81] or dynamic [82][83][84][85] PLE equipment has been used. Commercial laboratory-scale equipment commonly used for PLE was developed by the Dionex Corporation in 1995 and it can only be operated in static (batch) mode while some in-house equipment can be used in dynamic mode (continuous flow) [86].…”

Compressed fluids for the extraction of bioactive compounds

“…Not only antioxidant compounds have been extracted by SWE but also other bioactive compounds possessing different activities. For instance, SWE has enabled to obtain extract with anti-inflammatory properties from hop (Humulus lupulus) [153] or antimicrobial [119,154] or antiviral activity [126,155] from algae. In addition, SWE has also been employed as a final step to separate dietary fibers from the residue obtained by supercritical CO2 of citrus, demonstrating the importance of sequential methodologies for the recovery of valuable compounds from citrus fruit waste [157].…”

Health benefit of fucosterol from marine algae: a review

“…Santoyo et al evaluated the capability of pressurized liquid extraction (PLE) to isolate antiviral compounds against Herpes simplex virus type 1 (HSV‐1) from the edible seaweed Himanthalia elongata . The different viral infection phases were monitored in terms of the antiviral effects of the PLE extracts (hexane, ethanol and water).…”

“…A gas chromatographic–mass spectrometric analysis of the hexane and ethanol extracts revealed that the antiviral activity of the hexane extract was due to the existence of fucosterol. The research of Santoyo et al showed that PLE is a promising method for isolating antiviral constituents from H. elongata …”

“…Santoyo et al evaluated the capability of pressurized liquid extraction (PLE) to isolate antiviral compounds against Herpes simplex virus type 1 (HSV-1) from the edible seaweed Himanthalia elongata. 18 The different viral infection phases were monitored in terms of the antiviral effects of the PLE extracts (hexane, ethanol and water). Vero cells pretreated with 75 μg mL −1 of ethanol extract repressed viral infection approximately by 90%, while water and hexane extracts at the identical concentration reduced the viral infection to 78% and 70%.…”