Antimicrobial Properties of Seaweeds

Abstract

Antimicrobial activity is defined as the ability to destroy or inhibit the growth of microorganisms. Antimicrobial compounds are naturally occurring or synthetic organic compounds having antimicrobial activity. Recently, scientists have discovered many pharmaceutically active compounds that have antibacterial, antifungal, antiviral and antiprotozoal activities in seaweeds. To thrive in various environmental stresses, seaweed produces different metabolites such as polyphenols, polysaccharides, proteins, fatty acids, and pigments. These bioactive compounds are responsible for the antimicrobial activity exerted by seaweed. The antimicrobial activity of seaweed is influenced by various factors, such as the type of seaweed extract used, the target microorganisms, and the environmental conditions. The composition of the bioactive compounds from seaweed may depend on the extraction method and the solvent. It also depends on the seaweed sample, such as fresh or dried sample. Different mechanisms are followed by seaweed extract to acquire antimicrobial activities. Seaweed extracts exhibit various inhibition mechanisms, including disruption of the cell membrane, inhibition of target microorganism enzymes, and prevention of microorganism association with cellular receptors of the host cell. The location, salinity, temperature, etc. of the marine environment may affect the chemical composition of the bioactive compounds present in the seaweeds. The antimicrobial activity of seaweed can be evaluated in both in vitro and in vivo assays. Antimicrobial susceptibility tests and antimicrobial resistance tests are carried out by in vitro methods. The antimicrobial activity of seaweed can be a promising source in many applications, such as therapeutic applications, food industries, aquaculture, and biofouling.