Poster Presenter

On the antimicrobial activity of cell extracts of microalgae and cyanobacteria against foodborne bacteria
A. Catarina Guedes, Helena M. Amaro & F. Xavier Malcata
Portugal

Cyanobacteria and microalgae are highly productive and efficient biological systems, in terms of metabolic versatility and biochemical diversity.

In efforts to discover novel pharmaceutical compounds, screening for antibacterial features has been comprehensively carried out in higher plants; microalgae, in general, and cyanobacteria, in particular, have not yet received a similar attention. However, their relatively high growth rate, simple growth requirements, amenability to controlled laboratory culture, ubiquity and biodiversity make them suitable candidates for eventual commercial production of said compounds.

In this work, intra- and extracellular extracts of 13 cyanobacteria and 23 microalgae, were assayed for, via a visual turbidity test using a linear scale, with the aim of making a preliminary qualitative and discriminatory screening; the target pathogenic bacteria considered were Salmonella sp., Pseudomonas aeruginosa, Escherichia coli and Staphylococcus aureus, obtained from food and clinical isolates.

Scenedesmus obliquus strain M2-1 was the microalga that exhibited the highest antibacterial activity in terms of extracellular extracts, followed by extracellular extracts of Pavlova lutheri strain I#25 and intracellular extracts of S. obliquus strain B, against the aforementioned pathogens.