关键词: 嗜酸乳杆菌, 细菌素, 生物学特性

Abstract:

Without the presence of organic acids or hydrogen peroxide, some biological characteristics such as antibacterial
activity, thermal stability, optimal pH and protease sensitivity of the bacteriocin lactobacillin XH1 produced by Lactobacillus
acidophilus were explored. The results indicated lactobacillin XH1, a broad-spectrum antimicrobial substance, could inhibit
Escherichia coli, Staphylococcus aureus and Bacillus anthraci. The optimal activity was detected under the condition of
pH 1.0－5.0 and the optimal pH was 2.0－3.0. Subjected to treatment at 121 ℃ for 20 min, lactobacillin XH1 remained unchanged
and revealed certain thermal stability. Meanwhile, lactobacillin XH1 was sensitive to trypsin, pepsin and papain, but insensitive to
proteinase K and neutral protease. Its molecular weight was approximately 30 kD as identified by Tricine-SDS-PAGE.

Key words: Lactobacillus acidophilus, bacteriocin, biological characteristics