Phd in CELL AND DEVELOPMENTAL BIOLOGY

Thesis title: Enhancement of waste from the dairy industry: production of a fermented product based on Buffalo cheese whey with nutraceutical properties.

The high production of cheese whey from the dairy industry has made it necessary to find a solution for the recovery of this by-product rich in organic components which, if dispersed in the environment, would be very polluting and harmful to the ecosystem. The recovery of cheese whey is therefore important as it is very rich in different molecules and compounds that can have a beneficial effect on human health by acting on the cardiovascular system, the immune system, the gastrointestinal tract, the nervous system and metabolic health (Mehra et al., 2021). One of the methods used for the recovery and valorization of cheese whey is fermentation, which thanks to the action of the native microflora combined with the added technological strains can give a product with added value. Not only the molecules obtained from fermentation or those already naturally present can have a positive effect on the consumer, but also the microbial population can perform a probiotic action with improvement of human health. In this context, thanks to metabarcoding, it was useful to understand which bacterial and fungal species are present in Bufala Campana cheese whey. This was associated with a screening of the microbial population, useful for the isolation of species that can be grown on a plate and to have an idea of ​​which species are the most abundant in the raw material. DNA sequencing was performed on some strains isolated in this way, which revealed the presence of technologically interesting species and on which the potential probiotic and prebiotic capacity was tested, a phenotypic and robustness characterization was carried out. The isolated yeast strains were then used for the fermentation of buffalo cheese whey and the product obtained was tested for its antioxidant capacity, antihypertensive and antidiabetic activity and for the content of vitamins B6 and B9, demonstrating how fermentation can lead to the obtaining of a product with added value and how it can be considered as a way of recovering waste materials to promote a circular economy.