Microbial biodiversity of traditional fermented products from the Lazio region in Italy

The typical products of the Lazio region are characterized by a variety of native microorganisms that confer unique organoleptic and sensory properties. This project aims to isolate and characterize both genotypically and phenotypically the key microorganisms involved in typical food productions of the Lazio region. The primary goal is to have a detailed mapping of microbial biodiversity to contribute to the valorization of these products. A total of 29 samples of typical products were collected from local producers in various areas. These samples included 27 cheeses, 1 milk sample, and 1 salami sample. Microorganism isolation was performed using standard microbiological analyses on selective media incubated at different temperatures. A total of 874 colonies were subjected to phenotypic characterization based on morphology, Gram reaction, and the presence of specific enzymes such as oxidase and catalase. For precise identification at the species and genus level, molecular methods based on DNA analysis were employed. DNA was extracted from the isolated colonies using commercial kits. The 16S rRNA gene is a highly conserved region of the 16S ribosomal RNA present in all bacteria and characterized by variable regions that allow for bacterial discrimination at the species level. This gene was amplified by PCR and sequenced. The obtained sequences were compared against reference sequence databases to identify the microorganisms present in the samples. Results revealed the presence of genera Lactococcus, Streptococcus, Staphylococcus, and Enterococcus. These findings suggest a rich microbial diversity within the samples.