Characterization of Lactobacillus isolates from infant faeces as dietary adjuncts

Lactobacillus paracasei subsp. paracasei (six strains), Lb, rhamnosus (six strains), Lb. acidophilus (two strains), Lb. gasseri (three strains) and Lb . reuteri (three strains) isolates from new-born infants were tested for th eir ability to grow and metabolize in milk and to resist specific condition s of the gastrointestinal tract Many of the tested strains had desirable pr operties concerning their ability to withstand adverse conditions of the ga strointestinal tract and produce carbonyl compounds. In general strains of Lb. paracasei subsp. paracasei and Lb. rhamnosus were more resistant to low pH of the stomach than all the other strains. On the other hand, Lb, gasse ri and Lb, reuteri strains did not acidify milk. Thus, Lb. paracasei subsp. paracasei, Lb. acidophilus and Lb. rhamnosus strains could be preferably u sed as starters to produce fermented milks with possibly interesting organo leptic properties, as well as dietary and possible therapeutic importance. (C) 2000 Academic Press.