Colonic microbiome modulation and metabolic effects of Bryndza sheep cheese in pediatric acute lymphoblastic leukemia: An in vitro study

This study investigated the effects of lyophilized, unpasteurized Bryndza sheep cheese powder on gut microbiota and short-chain fatty acid (SCFA) production using an in vitro colonic fermentation model of pediatric acute lymphoblastic leukemia (ALL) patients. Low-dose (LD; 500 mg) and high-dose (HD; 1000 mg) treatments led to distinct microbial shifts within 48 h, affecting Firmicutes , Bacteroidota , and Proteobacteria . The α-diversity decreased in LD ( p < 0.05) but remained highest in HD ( p ≤ 0.01) after 48 h. Parasutterella and Enterococcus were enriched at 6 h, with HD promoting SCFA-producing bacteria ( Faecalibacterium ) at later stages. By 48 h, the HD increased Eubacterium hallii , Faecalibacterium , and Bacteroides , whereas LD enriched Lachnospira and Veillonella . Both treatments significantly increased acetate production ( p ≤ 0.01), with network analysis linking key microbiota families to SCFA production. Bryndza cheese modulates gut microbiota dose- and time-dependently, fostering SCFA-producing taxa and potentially improving gut health in pediatric ALL patients. • Bryndza sheep cheese significantly modulates colonic microbiota composition in vitro . • High-dose treatment enhances microbial diversity and production of short-chain fatty acids (SCFAs) in patients with cancer. • High-dose cheese enriched beneficial SCFA-producing taxa, such as Faecalibacterium and Butyricicoccus . • Study provides novel insights into gut microbiota-targeted nutritional interventions in oncology.