Antiviral Activity and Mechanisms of Seaweeds Bioactive Compounds on Enveloped Viruses-A Review

Abstract

In the last decades, the interest in seaweed has significantly increased. Bioactive compounds from seaweed's currently receive major attention from pharmaceutical companies as they express several interesting biological activities which are beneficial for humans. The structural diversity of seaweed metabolites provides diverse biological activities which are expressed through diverse mechanisms of actions. This review mainly focuses on the antiviral activity of seaweed's extracts, highlighting the mechanisms of actions of some seaweed molecules against infection caused by different types of enveloped viruses: influenza, Lentivirus (HIV-1), Herpes viruses, and coronaviruses. Seaweed metabolites with antiviral properties can act trough different pathways by increasing the host's defense system or through targeting and blocking virus replication before it enters host cells. Several studies have already established the large antiviral spectrum of seaweed's bioactive compounds. Throughout this review, antiviral mechanisms and medical applications of seaweed's bioactive compounds are analyzed, suggesting seaweed's potential source of antiviral compounds for the formulation of novel and natural antiviral drugs.

Keywords: HIV; HSV; IAV; antiviral activity; enveloped virus; polyphenol; polysaccharide; seaweed.

Figure 1

Schematic representation of influenza virus mechanism of cell infection. ① the spike protein hemagglutinin bond with the receptor on the host cell membrane; ② the virus enters into the cell by endocytosis; ③ the spike protein neuraminidase mediates the viral RNA and release, which enters the nucleus where it is replicated by the viral RNA polymerase; ④ viral mRNA is used to make viral proteins; ⑤ new viral particles are released into the extracellular matrix and the host cell continues to make new virus particles.

Figure 2

Schematic representation of HIV infection. ① binding of the virus to the host cell membrane; ② fusion of the virus and uncoating: the virus core uncoats into the cytoplasm of the target cell freeing the viral RNA; ③ reverse transcription: the viral RNA is transcribed into an RNA/DNA hybrid double helix; ④ integration of the viral gene to human DNA; ⑤ replication; ⑥ assembly of the new viral particles and proteins; ⑦ budding process and release of the new virus.