Viability of Lactobacillus gasseri and Its Cholesterol-Binding and Antimutagenic Activities During Subsequent Refrigerated Storage in Nonfermented Milk

¹ Faculty of Agriculture, Shinshu University, Minamiminowa, Nagano-ken, 399-4598, Japan

The effect storage at 4°C on the viability of Lactobacillus gasseri and its sodium taurocholate-deconjugating and cholesterol-binding abilities as well as desmutagenic activity was investigated. Unfermented milks containing L. gasseri strains SBT0274 and SBT0270 at 10⁹ cfu/ml were prepared using 10% skim milk. Total and bile-tolerant lactobacilli for strains SBT0274 and SBT0270 generally decreased after 14 d of storage at 4°C; however, viable cells of these strains were still at 10⁸ cfu/ml after 28 d of storage. The amounts of cholic acid released and of cholesterol bound by strains SBT0274 and SBT0270 declined over time, especially at 21 d of storage. Antimutagenic activity of unfermented milk made from both strains was attributed to the bacterial cells, and the activity was stable during storage at 4°C for 28 d.

Key Words: viability • sodium taurocholate deconjugation • cholesterol-binding ability • antimutagenicity

Submitted on March 11, 1999
Accepted on August 8, 1999