IMPIEGO DI BATTERI LATTICI PRODUTTORI DI FOLATI, ACIDO LINOLEICO CONIUGATO E RIDUCENTI IL COLESTEROLO PER LO SVILUPPO DI ALIMENTI FUNZIONALI

Folate and CLA-producing lactic acid bacteria and their cholesterol-lowering potential for the development of functional foods - Lactic acid bacteria (LAB), besides expressing an important acidifying activity, are also able to synthesize compounds promoting human health such as folate and conjugated linoleic acid (CLA) and reduce others such as cholesterol. A total of 200 LAB belonging to different genera and species were evaluated in order to identify the highest performing strains for the subsequent development of functional foods. The tests were preliminarily conducted in vitro and subsequently in experimental cheese-makings. Folate were determined by enzyme immunoassay and microbiological tests and CLA and cholesterol by gas chromatography analysis. A Lactobacillus casei (VC199) and two Lb. plantarum (VS166 and SE148) were the best folate producing strains reaching a content of 110 ?g/100 g in cheese. Lb. plantarum VC233 and Streptococcus thermophilus VC24 and VC115 produced CLA in vitro at a rate of over 13% of the precursor (linoleic acid) added to the medium. Seven strains (Lb. plantarum VS166 and VS513, Lb. casei VC199, Lb. paracasei SE160 and VC213, Enterococcus lactis BT161, E. faecium VC223) lowered the cholesterol content by more than 40% in vitro and two (VC199 and VS513 ) of more than 20% in goat cheese. Cholesterol lowering activity of Lb. casei VC199 was further tested in Crescenza providing a 13% reduction. LAB strains capable of producing functional biomolecules in significant amounts in vitro were identified and preliminary tests conducted in cheese provided strong evidence for the development of innovative fermented products with enhanced health properties.