The Fascinating World Of Microalgae And Its Application Potential

Humans have eaten seaweeds for millennia but microalgae are now usually seen as harmful organisms because they often produce some unpleasant phenomena such as red tides, mucilage etc. Microalgae are, on the contrary, very important as primary producers in aquatic environments, they exhibit large photosynthetic efficiency, using light approximately three times more efficiently than higher plants. As food they are important, almost the entire organism is nutritionally useful having very few indigestible structures. This was the oldest way of using microalgae by humans, but at present researchers discovered their tremendous potential for many different applicative uses. Microalgae are the fastest growing plants approximately doubling their weight once a day requiring raw and inexpensive materials. Many different species can be cultivate in a lot of ways depending on the selected aim and are a source of many interesting compounds: pigments, proteins, polysaccharides, enzymes, fats, some unusual bioactive molecules that have high value in many different applications. We cultivated in laboratory some diatom and dinoflagellate species isolated from the Adriatic Sea for studying their growth potential and their capability of lipid production. Batch cultures were grown in modified f/2 medium and collected by centrifugation during the stationary phase. After total lipid extraction, sterols, fatty acid methyl esters and hydrocarbons were analysed by gas chromathography and by gas chromathography-mass spectrometry. We confirmed that the most interesting PUFA or sterols are of microalgal origin but at present we can assume these compounds so useful for our general welfare only eating fishes or other aquatic animals. We think that in the next future it could be very interesting to extract these useful molecules from microalgae cultivated in controlled conditions, keeping in mind that both the choice of species and ambient conditions could be very important in producing different compounds