Abstract: Pentocin 31-1, produced by Lactobacillus pentosus 31-1 isolated from the traditional China fermented Xuan-Wei Ham, coud be adsorbed selectively on its producer at different pH conditions. At pH5.0, the adsorption rate was 75%, while below pH 3.0 or above pH7.0, Pentocin 31-1 wasn’t adsorbed at all. On the basis of this property, by changing pH, Pentocin 31-1 was adsorbed at pH5.0 and released at pH7.0. The efficiency of isolation and purification was high. The specific activity of Pentocin 31-1was increased 33 fold with a yield of 45%. The active extract was further subjected to Tricine-SDS-PAGE. The result showed that two bands appeared, where most of the activity corresponded to the band with molecular weight between 6400～ 14000 D. It is simple and effective, could be used as commercial preparations for food industry.

Key words: bacteriocin, adsorption-desorption, purification, Tricine-SDS-PAGE