Research Projects

ABSTRACT

Microalgae represent a good source of nutrients and bioactive compounds and thus can contribute to human health. In the Slovenian market microalgae are currently found in the form of tablets, capsules and liquids for use as dietary supplements. The efficacies and origins of such dietary supplements are generally unknown, because they are not under strict regulation as medicines or food. Thus, regular monitoring of such products that are available on the market is of great importance. The compositions and nutritional values of microalgae depend heavily on geographic area and season. In the framework of the project we will define control parameters and standard methods for their determination. Thus, advanced analytical techniques will be used to ensure quality, safety and traceability of dietary supplements based on Spirulina and Chlorella and available on the market. On other hand, establishment of large-scale cultivation technologies will enable that Spirulina and Chlorella will be produced under controlled and optimised conditions. This will led to controlled quality of products, which can still be improved with further processing. Lactic acid fermentation can be used to improve nutritional properties, as well as the functional value of the substrates and to enhance their shelf life, safety and sensory characteristics. It can enhance the efficiency of original bioactive compounds via their release or transformation by lactic acid bacteria, and can enrich the substrate with their metabolites (e.g., polysaccharides, biaoctive peptides, vitamin B12, short-chain fatty acids). This can thus improve the functional value of such subtrates. As Spirulina and Chlorella contain many functional bioactive costituents (e.g., long-chain polyunsaturated fatty acids, phenolic compounds, sterols, proteins, amino acids, peptides, vitamins A, C, E, K, polysaccharides, pigments) with different activities, lactic acid fermentation will be used to prepare food products based on microalgae that have better nutritional and functional characteristics compared to the original biomass. To test this hypotesis, chemical, biochemical and microbiological characterisation before and after fermentation as well as bioactivity assays using molecular, cell and animal models to define the physiological effects will be performed.  Although some studies have dealt with lactic acid fermentation of microalgae, there have been no reports to date on the evaluation of the impact of lactic acid fermentation on the composition of the nutrients and bioactive compounds of microalgae biomass, nor on their microbiological stability and bioactivity in the context of novel functional food products. As well as Spirulina and Chlorella, which are the most studied among the microalgae in terms of their nutritional and functional properties, there are other microalgae that populate different environmental niches that can biosynthesise a great diversity of metabolites. Thus many of these have potential applications in the food, pharmaceutical and cosmetics industries. Thus, extreme environmental niches in Slovenia like salt pans, healing springs and underground caves will be explored. They might represent interesting places in the search for microalgae that contain new metabolites and thus represent candidates for novel food constituents. With the exception of Karst caves, such extreme habitats in Slovenia have not been explored. In summary, the proposed project will be focused on

• microalgae Spirulina and Chlorella from dietary supplements available on the Slovenian market with unknown origin and efficiency,
• those arising from large-scale cultivation systems with known origin and controlled quality, which can still be improved using biotechnological approach and thus obtained functional food and
• microalgae from extreme habitats in Slovenia as potential candidates for novel food constituents as well as other biotechnologically interesting products.

THE PHASES OF THE PROJECT AND THEIR REALIZATION

1. Introduction of biotechnological approach (lactic acid fermentation of Spirulina and Chlorella biomass) to improve functional value of original microalgal biomass and characterization of microalgal biomass before and after fermentation in the context of quality, safety and bioactivity using cell and animal models.
2. Determination of origin and efficiency of Spirulina and Chlorella dietary supplements already found on the Slovenian market.
3. Evaluation of biodiversity of microalgae in Slovenia – a list of current state and new extreme habitats

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