| Summary: | Marine macro algae possess many beneficial bioactive properties which can be of interest in various applications. Components of interest in seaweed are for instance sulfated polysaccharides, defined as fucoidan, with antimicrobial activities and polyphenols with antioxidative properties. This study analyses the antimicrobial effect of two extracts from Fucus vesiculosus and test their efficacy on five different test microorganisms. Both extracts derived from seaweed harvested outside the shore of Iceland in June 2012 respectively June 2015. The extract from seaweed collected 2015 was filtered to retain components larger than 100 kDa, and the extract derived from algae harvested in 2012 was unfiltered and thus contained components within the full range of size. Composition analysis on the seaweed extracts revealed that the composition of the seaweeds were fairly similar despite the different preparations. The filtered extract had a composition of 21.2 % carbohydrate, 6.1 % protein, 3.4 % phenol, 0.3 % fat and 31.5 % ash. The composition of the unfiltered extract were 18.0 % carbohydrate, 5.1 % protein, 5.3 % phenol, 0.6 % fat and 35.3 % ash. Turbidity tests for antimicrobial activity showed that high concentration of the unfiltered unsterilized extract was most efficient against growth of E. coli. The filtered extract autoclaved as powder met the acceptance criteria from the European pharmacopoeia for S. aureus and A. brasiliensis in the efficacy test. The filtered extract autoclaved in liquid form did not meet the criteria of acceptance for four microbes, and the results for A. brasiliensis were ambiguous. Because of the antimicrobial effects and antioxidative properties of F. vesiculosus interest has been shown to use the algae in food protection against oxidation of desired components and to prolong the time of storage. The brown macroalgae, bladder wrack, which is abundant in mainly North Atlantic and Pacific Ocean, possess a variety of bioactivities. The bioactive polysaccharides, fucoidan, were of special ...
|
|---|